| /* |
| * Copyright (c) 2010, 2013, Oracle and/or its affiliates. All rights reserved. |
| * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| * |
| * This code is free software; you can redistribute it and/or modify it |
| * under the terms of the GNU General Public License version 2 only, as |
| * published by the Free Software Foundation. Oracle designates this |
| * particular file as subject to the "Classpath" exception as provided |
| * by Oracle in the LICENSE file that accompanied this code. |
| * |
| * This code is distributed in the hope that it will be useful, but WITHOUT |
| * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
| * version 2 for more details (a copy is included in the LICENSE file that |
| * accompanied this code). |
| * |
| * You should have received a copy of the GNU General Public License version |
| * 2 along with this work; if not, write to the Free Software Foundation, |
| * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
| * |
| * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
| * or visit www.oracle.com if you need additional information or have any |
| * questions. |
| */ |
| |
| package jdk.nashorn.internal.codegen; |
| |
| import static jdk.nashorn.internal.codegen.ClassEmitter.Flag.PRIVATE; |
| import static jdk.nashorn.internal.codegen.ClassEmitter.Flag.STATIC; |
| import static jdk.nashorn.internal.codegen.CompilerConstants.ARGUMENTS; |
| import static jdk.nashorn.internal.codegen.CompilerConstants.CALLEE; |
| import static jdk.nashorn.internal.codegen.CompilerConstants.CREATE_PROGRAM_FUNCTION; |
| import static jdk.nashorn.internal.codegen.CompilerConstants.GET_MAP; |
| import static jdk.nashorn.internal.codegen.CompilerConstants.GET_STRING; |
| import static jdk.nashorn.internal.codegen.CompilerConstants.QUICK_PREFIX; |
| import static jdk.nashorn.internal.codegen.CompilerConstants.REGEX_PREFIX; |
| import static jdk.nashorn.internal.codegen.CompilerConstants.SCOPE; |
| import static jdk.nashorn.internal.codegen.CompilerConstants.SPLIT_PREFIX; |
| import static jdk.nashorn.internal.codegen.CompilerConstants.THIS; |
| import static jdk.nashorn.internal.codegen.CompilerConstants.VARARGS; |
| import static jdk.nashorn.internal.codegen.CompilerConstants.interfaceCallNoLookup; |
| import static jdk.nashorn.internal.codegen.CompilerConstants.methodDescriptor; |
| import static jdk.nashorn.internal.codegen.CompilerConstants.staticCallNoLookup; |
| import static jdk.nashorn.internal.codegen.CompilerConstants.typeDescriptor; |
| import static jdk.nashorn.internal.codegen.CompilerConstants.virtualCallNoLookup; |
| import static jdk.nashorn.internal.ir.Symbol.HAS_SLOT; |
| import static jdk.nashorn.internal.ir.Symbol.IS_INTERNAL; |
| import static jdk.nashorn.internal.runtime.UnwarrantedOptimismException.INVALID_PROGRAM_POINT; |
| import static jdk.nashorn.internal.runtime.UnwarrantedOptimismException.isValid; |
| import static jdk.nashorn.internal.runtime.linker.NashornCallSiteDescriptor.CALLSITE_APPLY_TO_CALL; |
| import static jdk.nashorn.internal.runtime.linker.NashornCallSiteDescriptor.CALLSITE_DECLARE; |
| import static jdk.nashorn.internal.runtime.linker.NashornCallSiteDescriptor.CALLSITE_FAST_SCOPE; |
| import static jdk.nashorn.internal.runtime.linker.NashornCallSiteDescriptor.CALLSITE_OPTIMISTIC; |
| import static jdk.nashorn.internal.runtime.linker.NashornCallSiteDescriptor.CALLSITE_PROGRAM_POINT_SHIFT; |
| import static jdk.nashorn.internal.runtime.linker.NashornCallSiteDescriptor.CALLSITE_SCOPE; |
| |
| import java.io.PrintWriter; |
| import java.util.ArrayDeque; |
| import java.util.ArrayList; |
| import java.util.Arrays; |
| import java.util.BitSet; |
| import java.util.Collection; |
| import java.util.Collections; |
| import java.util.Deque; |
| import java.util.EnumSet; |
| import java.util.HashMap; |
| import java.util.HashSet; |
| import java.util.Iterator; |
| import java.util.LinkedList; |
| import java.util.List; |
| import java.util.Map; |
| import java.util.Set; |
| import java.util.TreeMap; |
| import java.util.function.Supplier; |
| import jdk.nashorn.internal.AssertsEnabled; |
| import jdk.nashorn.internal.IntDeque; |
| import jdk.nashorn.internal.codegen.ClassEmitter.Flag; |
| import jdk.nashorn.internal.codegen.CompilerConstants.Call; |
| import jdk.nashorn.internal.codegen.types.ArrayType; |
| import jdk.nashorn.internal.codegen.types.Type; |
| import jdk.nashorn.internal.ir.AccessNode; |
| import jdk.nashorn.internal.ir.BaseNode; |
| import jdk.nashorn.internal.ir.BinaryNode; |
| import jdk.nashorn.internal.ir.Block; |
| import jdk.nashorn.internal.ir.BlockStatement; |
| import jdk.nashorn.internal.ir.BreakNode; |
| import jdk.nashorn.internal.ir.CallNode; |
| import jdk.nashorn.internal.ir.CaseNode; |
| import jdk.nashorn.internal.ir.CatchNode; |
| import jdk.nashorn.internal.ir.ContinueNode; |
| import jdk.nashorn.internal.ir.EmptyNode; |
| import jdk.nashorn.internal.ir.Expression; |
| import jdk.nashorn.internal.ir.ExpressionStatement; |
| import jdk.nashorn.internal.ir.ForNode; |
| import jdk.nashorn.internal.ir.FunctionNode; |
| import jdk.nashorn.internal.ir.GetSplitState; |
| import jdk.nashorn.internal.ir.IdentNode; |
| import jdk.nashorn.internal.ir.IfNode; |
| import jdk.nashorn.internal.ir.IndexNode; |
| import jdk.nashorn.internal.ir.JoinPredecessorExpression; |
| import jdk.nashorn.internal.ir.JumpStatement; |
| import jdk.nashorn.internal.ir.JumpToInlinedFinally; |
| import jdk.nashorn.internal.ir.LabelNode; |
| import jdk.nashorn.internal.ir.LexicalContext; |
| import jdk.nashorn.internal.ir.LexicalContextNode; |
| import jdk.nashorn.internal.ir.LiteralNode; |
| import jdk.nashorn.internal.ir.LiteralNode.ArrayLiteralNode; |
| import jdk.nashorn.internal.ir.LiteralNode.PrimitiveLiteralNode; |
| import jdk.nashorn.internal.ir.LocalVariableConversion; |
| import jdk.nashorn.internal.ir.LoopNode; |
| import jdk.nashorn.internal.ir.Node; |
| import jdk.nashorn.internal.ir.ObjectNode; |
| import jdk.nashorn.internal.ir.Optimistic; |
| import jdk.nashorn.internal.ir.PropertyNode; |
| import jdk.nashorn.internal.ir.ReturnNode; |
| import jdk.nashorn.internal.ir.RuntimeNode; |
| import jdk.nashorn.internal.ir.RuntimeNode.Request; |
| import jdk.nashorn.internal.ir.SetSplitState; |
| import jdk.nashorn.internal.ir.SplitReturn; |
| import jdk.nashorn.internal.ir.Splittable; |
| import jdk.nashorn.internal.ir.Statement; |
| import jdk.nashorn.internal.ir.SwitchNode; |
| import jdk.nashorn.internal.ir.Symbol; |
| import jdk.nashorn.internal.ir.TernaryNode; |
| import jdk.nashorn.internal.ir.ThrowNode; |
| import jdk.nashorn.internal.ir.TryNode; |
| import jdk.nashorn.internal.ir.UnaryNode; |
| import jdk.nashorn.internal.ir.VarNode; |
| import jdk.nashorn.internal.ir.WhileNode; |
| import jdk.nashorn.internal.ir.WithNode; |
| import jdk.nashorn.internal.ir.visitor.NodeOperatorVisitor; |
| import jdk.nashorn.internal.ir.visitor.SimpleNodeVisitor; |
| import jdk.nashorn.internal.objects.Global; |
| import jdk.nashorn.internal.parser.Lexer.RegexToken; |
| import jdk.nashorn.internal.parser.TokenType; |
| import jdk.nashorn.internal.runtime.Context; |
| import jdk.nashorn.internal.runtime.Debug; |
| import jdk.nashorn.internal.runtime.ECMAException; |
| import jdk.nashorn.internal.runtime.JSType; |
| import jdk.nashorn.internal.runtime.OptimisticReturnFilters; |
| import jdk.nashorn.internal.runtime.PropertyMap; |
| import jdk.nashorn.internal.runtime.RecompilableScriptFunctionData; |
| import jdk.nashorn.internal.runtime.RewriteException; |
| import jdk.nashorn.internal.runtime.Scope; |
| import jdk.nashorn.internal.runtime.ScriptEnvironment; |
| import jdk.nashorn.internal.runtime.ScriptFunction; |
| import jdk.nashorn.internal.runtime.ScriptObject; |
| import jdk.nashorn.internal.runtime.ScriptRuntime; |
| import jdk.nashorn.internal.runtime.Source; |
| import jdk.nashorn.internal.runtime.Undefined; |
| import jdk.nashorn.internal.runtime.UnwarrantedOptimismException; |
| import jdk.nashorn.internal.runtime.arrays.ArrayData; |
| import jdk.nashorn.internal.runtime.linker.LinkerCallSite; |
| import jdk.nashorn.internal.runtime.logging.DebugLogger; |
| import jdk.nashorn.internal.runtime.logging.Loggable; |
| import jdk.nashorn.internal.runtime.logging.Logger; |
| import jdk.nashorn.internal.runtime.options.Options; |
| |
| /** |
| * This is the lowest tier of the code generator. It takes lowered ASTs emitted |
| * from Lower and emits Java byte code. The byte code emission logic is broken |
| * out into MethodEmitter. MethodEmitter works internally with a type stack, and |
| * keeps track of the contents of the byte code stack. This way we avoid a large |
| * number of special cases on the form |
| * <pre> |
| * if (type == INT) { |
| * visitInsn(ILOAD, slot); |
| * } else if (type == DOUBLE) { |
| * visitInsn(DOUBLE, slot); |
| * } |
| * </pre> |
| * This quickly became apparent when the code generator was generalized to work |
| * with all types, and not just numbers or objects. |
| * <p> |
| * The CodeGenerator visits nodes only once and emits bytecode for them. |
| */ |
| @Logger(name="codegen") |
| final class CodeGenerator extends NodeOperatorVisitor<CodeGeneratorLexicalContext> implements Loggable { |
| |
| private static final Type SCOPE_TYPE = Type.typeFor(ScriptObject.class); |
| |
| private static final String GLOBAL_OBJECT = Type.getInternalName(Global.class); |
| |
| private static final Call CREATE_REWRITE_EXCEPTION = CompilerConstants.staticCallNoLookup(RewriteException.class, |
| "create", RewriteException.class, UnwarrantedOptimismException.class, Object[].class, String[].class); |
| private static final Call CREATE_REWRITE_EXCEPTION_REST_OF = CompilerConstants.staticCallNoLookup(RewriteException.class, |
| "create", RewriteException.class, UnwarrantedOptimismException.class, Object[].class, String[].class, int[].class); |
| |
| private static final Call ENSURE_INT = CompilerConstants.staticCallNoLookup(OptimisticReturnFilters.class, |
| "ensureInt", int.class, Object.class, int.class); |
| private static final Call ENSURE_LONG = CompilerConstants.staticCallNoLookup(OptimisticReturnFilters.class, |
| "ensureLong", long.class, Object.class, int.class); |
| private static final Call ENSURE_NUMBER = CompilerConstants.staticCallNoLookup(OptimisticReturnFilters.class, |
| "ensureNumber", double.class, Object.class, int.class); |
| |
| private static final Call CREATE_FUNCTION_OBJECT = CompilerConstants.staticCallNoLookup(ScriptFunction.class, |
| "create", ScriptFunction.class, Object[].class, int.class, ScriptObject.class); |
| private static final Call CREATE_FUNCTION_OBJECT_NO_SCOPE = CompilerConstants.staticCallNoLookup(ScriptFunction.class, |
| "create", ScriptFunction.class, Object[].class, int.class); |
| |
| private static final Call TO_NUMBER_FOR_EQ = CompilerConstants.staticCallNoLookup(JSType.class, |
| "toNumberForEq", double.class, Object.class); |
| private static final Call TO_NUMBER_FOR_STRICT_EQ = CompilerConstants.staticCallNoLookup(JSType.class, |
| "toNumberForStrictEq", double.class, Object.class); |
| |
| |
| private static final Class<?> ITERATOR_CLASS = Iterator.class; |
| static { |
| assert ITERATOR_CLASS == CompilerConstants.ITERATOR_PREFIX.type(); |
| } |
| private static final Type ITERATOR_TYPE = Type.typeFor(ITERATOR_CLASS); |
| private static final Type EXCEPTION_TYPE = Type.typeFor(CompilerConstants.EXCEPTION_PREFIX.type()); |
| |
| private static final Integer INT_ZERO = 0; |
| |
| /** Constant data & installation. The only reason the compiler keeps this is because it is assigned |
| * by reflection in class installation */ |
| private final Compiler compiler; |
| |
| /** Is the current code submitted by 'eval' call? */ |
| private final boolean evalCode; |
| |
| /** Call site flags given to the code generator to be used for all generated call sites */ |
| private final int callSiteFlags; |
| |
| /** How many regexp fields have been emitted */ |
| private int regexFieldCount; |
| |
| /** Line number for last statement. If we encounter a new line number, line number bytecode information |
| * needs to be generated */ |
| private int lastLineNumber = -1; |
| |
| /** When should we stop caching regexp expressions in fields to limit bytecode size? */ |
| private static final int MAX_REGEX_FIELDS = 2 * 1024; |
| |
| /** Current method emitter */ |
| private MethodEmitter method; |
| |
| /** Current compile unit */ |
| private CompileUnit unit; |
| |
| private final DebugLogger log; |
| |
| /** From what size should we use spill instead of fields for JavaScript objects? */ |
| static final int OBJECT_SPILL_THRESHOLD = Options.getIntProperty("nashorn.spill.threshold", 256); |
| |
| private final Set<String> emittedMethods = new HashSet<>(); |
| |
| // Function Id -> ContinuationInfo. Used by compilation of rest-of function only. |
| private ContinuationInfo continuationInfo; |
| |
| private final Deque<Label> scopeEntryLabels = new ArrayDeque<>(); |
| |
| private static final Label METHOD_BOUNDARY = new Label(""); |
| private final Deque<Label> catchLabels = new ArrayDeque<>(); |
| // Number of live locals on entry to (and thus also break from) labeled blocks. |
| private final IntDeque labeledBlockBreakLiveLocals = new IntDeque(); |
| |
| //is this a rest of compilation |
| private final int[] continuationEntryPoints; |
| |
| /** |
| * Constructor. |
| * |
| * @param compiler |
| */ |
| CodeGenerator(final Compiler compiler, final int[] continuationEntryPoints) { |
| super(new CodeGeneratorLexicalContext()); |
| this.compiler = compiler; |
| this.evalCode = compiler.getSource().isEvalCode(); |
| this.continuationEntryPoints = continuationEntryPoints; |
| this.callSiteFlags = compiler.getScriptEnvironment()._callsite_flags; |
| this.log = initLogger(compiler.getContext()); |
| } |
| |
| @Override |
| public DebugLogger getLogger() { |
| return log; |
| } |
| |
| @Override |
| public DebugLogger initLogger(final Context context) { |
| return context.getLogger(this.getClass()); |
| } |
| |
| /** |
| * Gets the call site flags, adding the strict flag if the current function |
| * being generated is in strict mode |
| * |
| * @return the correct flags for a call site in the current function |
| */ |
| int getCallSiteFlags() { |
| return lc.getCurrentFunction().getCallSiteFlags() | callSiteFlags; |
| } |
| |
| /** |
| * Gets the flags for a scope call site. |
| * @param symbol a scope symbol |
| * @return the correct flags for the scope call site |
| */ |
| private int getScopeCallSiteFlags(final Symbol symbol) { |
| assert symbol.isScope(); |
| final int flags = getCallSiteFlags() | CALLSITE_SCOPE; |
| if (isEvalCode() && symbol.isGlobal()) { |
| return flags; // Don't set fast-scope flag on non-declared globals in eval code - see JDK-8077955. |
| } |
| return isFastScope(symbol) ? flags | CALLSITE_FAST_SCOPE : flags; |
| } |
| |
| /** |
| * Are we generating code for 'eval' code? |
| * @return true if currently compiled code is 'eval' code. |
| */ |
| boolean isEvalCode() { |
| return evalCode; |
| } |
| |
| /** |
| * Are we using dual primitive/object field representation? |
| * @return true if using dual field representation, false for object-only fields |
| */ |
| boolean useDualFields() { |
| return compiler.getContext().useDualFields(); |
| } |
| |
| /** |
| * Load an identity node |
| * |
| * @param identNode an identity node to load |
| * @return the method generator used |
| */ |
| private MethodEmitter loadIdent(final IdentNode identNode, final TypeBounds resultBounds) { |
| checkTemporalDeadZone(identNode); |
| final Symbol symbol = identNode.getSymbol(); |
| |
| if (!symbol.isScope()) { |
| final Type type = identNode.getType(); |
| if(type == Type.UNDEFINED) { |
| return method.loadUndefined(resultBounds.widest); |
| } |
| |
| assert symbol.hasSlot() || symbol.isParam(); |
| return method.load(identNode); |
| } |
| |
| assert identNode.getSymbol().isScope() : identNode + " is not in scope!"; |
| final int flags = getScopeCallSiteFlags(symbol); |
| if (isFastScope(symbol)) { |
| // Only generate shared scope getter for fast-scope symbols so we know we can dial in correct scope. |
| if (symbol.getUseCount() > SharedScopeCall.FAST_SCOPE_GET_THRESHOLD && !identNode.isOptimistic()) { |
| // As shared scope vars are only used with non-optimistic identifiers, we switch from using TypeBounds to |
| // just a single definitive type, resultBounds.widest. |
| new OptimisticOperation(identNode, TypeBounds.OBJECT) { |
| @Override |
| void loadStack() { |
| method.loadCompilerConstant(SCOPE); |
| } |
| |
| @Override |
| void consumeStack() { |
| loadSharedScopeVar(resultBounds.widest, symbol, flags); |
| } |
| }.emit(); |
| } else { |
| new LoadFastScopeVar(identNode, resultBounds, flags).emit(); |
| } |
| } else { |
| //slow scope load, we have no proto depth |
| new LoadScopeVar(identNode, resultBounds, flags).emit(); |
| } |
| |
| return method; |
| } |
| |
| // Any access to LET and CONST variables before their declaration must throw ReferenceError. |
| // This is called the temporal dead zone (TDZ). See https://gist.github.com/rwaldron/f0807a758aa03bcdd58a |
| private void checkTemporalDeadZone(final IdentNode identNode) { |
| if (identNode.isDead()) { |
| method.load(identNode.getSymbol().getName()).invoke(ScriptRuntime.THROW_REFERENCE_ERROR); |
| } |
| } |
| |
| // Runtime check for assignment to ES6 const |
| private void checkAssignTarget(final Expression expression) { |
| if (expression instanceof IdentNode && ((IdentNode)expression).getSymbol().isConst()) { |
| method.load(((IdentNode)expression).getSymbol().getName()).invoke(ScriptRuntime.THROW_CONST_TYPE_ERROR); |
| } |
| } |
| |
| private boolean isRestOf() { |
| return continuationEntryPoints != null; |
| } |
| |
| private boolean isCurrentContinuationEntryPoint(final int programPoint) { |
| return isRestOf() && getCurrentContinuationEntryPoint() == programPoint; |
| } |
| |
| private int[] getContinuationEntryPoints() { |
| return isRestOf() ? continuationEntryPoints : null; |
| } |
| |
| private int getCurrentContinuationEntryPoint() { |
| return isRestOf() ? continuationEntryPoints[0] : INVALID_PROGRAM_POINT; |
| } |
| |
| private boolean isContinuationEntryPoint(final int programPoint) { |
| if (isRestOf()) { |
| assert continuationEntryPoints != null; |
| for (final int cep : continuationEntryPoints) { |
| if (cep == programPoint) { |
| return true; |
| } |
| } |
| } |
| return false; |
| } |
| |
| /** |
| * Check if this symbol can be accessed directly with a putfield or getfield or dynamic load |
| * |
| * @param symbol symbol to check for fast scope |
| * @return true if fast scope |
| */ |
| private boolean isFastScope(final Symbol symbol) { |
| if (!symbol.isScope()) { |
| return false; |
| } |
| |
| if (!lc.inDynamicScope()) { |
| // If there's no with or eval in context, and the symbol is marked as scoped, it is fast scoped. Such a |
| // symbol must either be global, or its defining block must need scope. |
| assert symbol.isGlobal() || lc.getDefiningBlock(symbol).needsScope() : symbol.getName(); |
| return true; |
| } |
| |
| if (symbol.isGlobal()) { |
| // Shortcut: if there's a with or eval in context, globals can't be fast scoped |
| return false; |
| } |
| |
| // Otherwise, check if there's a dynamic scope between use of the symbol and its definition |
| final String name = symbol.getName(); |
| boolean previousWasBlock = false; |
| for (final Iterator<LexicalContextNode> it = lc.getAllNodes(); it.hasNext();) { |
| final LexicalContextNode node = it.next(); |
| if (node instanceof Block) { |
| // If this block defines the symbol, then we can fast scope the symbol. |
| final Block block = (Block)node; |
| if (block.getExistingSymbol(name) == symbol) { |
| assert block.needsScope(); |
| return true; |
| } |
| previousWasBlock = true; |
| } else { |
| if (node instanceof WithNode && previousWasBlock || node instanceof FunctionNode && ((FunctionNode)node).needsDynamicScope()) { |
| // If we hit a scope that can have symbols introduced into it at run time before finding the defining |
| // block, the symbol can't be fast scoped. A WithNode only counts if we've immediately seen a block |
| // before - its block. Otherwise, we are currently processing the WithNode's expression, and that's |
| // obviously not subjected to introducing new symbols. |
| return false; |
| } |
| previousWasBlock = false; |
| } |
| } |
| // Should've found the symbol defined in a block |
| throw new AssertionError(); |
| } |
| |
| private MethodEmitter loadSharedScopeVar(final Type valueType, final Symbol symbol, final int flags) { |
| assert isFastScope(symbol); |
| method.load(getScopeProtoDepth(lc.getCurrentBlock(), symbol)); |
| return lc.getScopeGet(unit, symbol, valueType, flags).generateInvoke(method); |
| } |
| |
| private class LoadScopeVar extends OptimisticOperation { |
| final IdentNode identNode; |
| private final int flags; |
| |
| LoadScopeVar(final IdentNode identNode, final TypeBounds resultBounds, final int flags) { |
| super(identNode, resultBounds); |
| this.identNode = identNode; |
| this.flags = flags; |
| } |
| |
| @Override |
| void loadStack() { |
| method.loadCompilerConstant(SCOPE); |
| getProto(); |
| } |
| |
| void getProto() { |
| //empty |
| } |
| |
| @Override |
| void consumeStack() { |
| // If this is either __FILE__, __DIR__, or __LINE__ then load the property initially as Object as we'd convert |
| // it anyway for replaceLocationPropertyPlaceholder. |
| if(identNode.isCompileTimePropertyName()) { |
| method.dynamicGet(Type.OBJECT, identNode.getSymbol().getName(), flags, identNode.isFunction(), false); |
| replaceCompileTimeProperty(); |
| } else { |
| dynamicGet(identNode.getSymbol().getName(), flags, identNode.isFunction(), false); |
| } |
| } |
| } |
| |
| private class LoadFastScopeVar extends LoadScopeVar { |
| LoadFastScopeVar(final IdentNode identNode, final TypeBounds resultBounds, final int flags) { |
| super(identNode, resultBounds, flags); |
| } |
| |
| @Override |
| void getProto() { |
| loadFastScopeProto(identNode.getSymbol(), false); |
| } |
| } |
| |
| private MethodEmitter storeFastScopeVar(final Symbol symbol, final int flags) { |
| loadFastScopeProto(symbol, true); |
| method.dynamicSet(symbol.getName(), flags, false); |
| return method; |
| } |
| |
| private int getScopeProtoDepth(final Block startingBlock, final Symbol symbol) { |
| //walk up the chain from starting block and when we bump into the current function boundary, add the external |
| //information. |
| final FunctionNode fn = lc.getCurrentFunction(); |
| final int externalDepth = compiler.getScriptFunctionData(fn.getId()).getExternalSymbolDepth(symbol.getName()); |
| |
| //count the number of scopes from this place to the start of the function |
| |
| final int internalDepth = FindScopeDepths.findInternalDepth(lc, fn, startingBlock, symbol); |
| final int scopesToStart = FindScopeDepths.findScopesToStart(lc, fn, startingBlock); |
| int depth = 0; |
| if (internalDepth == -1) { |
| depth = scopesToStart + externalDepth; |
| } else { |
| assert internalDepth <= scopesToStart; |
| depth = internalDepth; |
| } |
| |
| return depth; |
| } |
| |
| private void loadFastScopeProto(final Symbol symbol, final boolean swap) { |
| final int depth = getScopeProtoDepth(lc.getCurrentBlock(), symbol); |
| assert depth != -1 : "Couldn't find scope depth for symbol " + symbol.getName() + " in " + lc.getCurrentFunction(); |
| if (depth > 0) { |
| if (swap) { |
| method.swap(); |
| } |
| for (int i = 0; i < depth; i++) { |
| method.invoke(ScriptObject.GET_PROTO); |
| } |
| if (swap) { |
| method.swap(); |
| } |
| } |
| } |
| |
| /** |
| * Generate code that loads this node to the stack, not constraining its type |
| * |
| * @param expr node to load |
| * |
| * @return the method emitter used |
| */ |
| private MethodEmitter loadExpressionUnbounded(final Expression expr) { |
| return loadExpression(expr, TypeBounds.UNBOUNDED); |
| } |
| |
| private MethodEmitter loadExpressionAsObject(final Expression expr) { |
| return loadExpression(expr, TypeBounds.OBJECT); |
| } |
| |
| MethodEmitter loadExpressionAsBoolean(final Expression expr) { |
| return loadExpression(expr, TypeBounds.BOOLEAN); |
| } |
| |
| // Test whether conversion from source to target involves a call of ES 9.1 ToPrimitive |
| // with possible side effects from calling an object's toString or valueOf methods. |
| private static boolean noToPrimitiveConversion(final Type source, final Type target) { |
| // Object to boolean conversion does not cause ToPrimitive call |
| return source.isJSPrimitive() || !target.isJSPrimitive() || target.isBoolean(); |
| } |
| |
| MethodEmitter loadBinaryOperands(final BinaryNode binaryNode) { |
| return loadBinaryOperands(binaryNode.lhs(), binaryNode.rhs(), TypeBounds.UNBOUNDED.notWiderThan(binaryNode.getWidestOperandType()), false, false); |
| } |
| |
| private MethodEmitter loadBinaryOperands(final Expression lhs, final Expression rhs, final TypeBounds explicitOperandBounds, final boolean baseAlreadyOnStack, final boolean forceConversionSeparation) { |
| // ECMAScript 5.1 specification (sections 11.5-11.11 and 11.13) prescribes that when evaluating a binary |
| // expression "LEFT op RIGHT", the order of operations must be: LOAD LEFT, LOAD RIGHT, CONVERT LEFT, CONVERT |
| // RIGHT, EXECUTE OP. Unfortunately, doing it in this order defeats potential optimizations that arise when we |
| // can combine a LOAD with a CONVERT operation (e.g. use a dynamic getter with the conversion target type as its |
| // return value). What we do here is reorder LOAD RIGHT and CONVERT LEFT when possible; it is possible only when |
| // we can prove that executing CONVERT LEFT can't have a side effect that changes the value of LOAD RIGHT. |
| // Basically, if we know that either LEFT already is a primitive value, or does not have to be converted to |
| // a primitive value, or RIGHT is an expression that loads without side effects, then we can do the |
| // reordering and collapse LOAD/CONVERT into a single operation; otherwise we need to do the more costly |
| // separate operations to preserve specification semantics. |
| |
| // Operands' load type should not be narrower than the narrowest of the individual operand types, nor narrower |
| // than the lower explicit bound, but it should also not be wider than |
| final Type lhsType = undefinedToNumber(lhs.getType()); |
| final Type rhsType = undefinedToNumber(rhs.getType()); |
| final Type narrowestOperandType = Type.narrowest(Type.widest(lhsType, rhsType), explicitOperandBounds.widest); |
| final TypeBounds operandBounds = explicitOperandBounds.notNarrowerThan(narrowestOperandType); |
| if (noToPrimitiveConversion(lhsType, explicitOperandBounds.widest) || rhs.isLocal()) { |
| // Can reorder. We might still need to separate conversion, but at least we can do it with reordering |
| if (forceConversionSeparation) { |
| // Can reorder, but can't move conversion into the operand as the operation depends on operands |
| // exact types for its overflow guarantees. E.g. with {L}{%I}expr1 {L}* {L}{%I}expr2 we are not allowed |
| // to merge {L}{%I} into {%L}, as that can cause subsequent overflows; test for JDK-8058610 contains |
| // concrete cases where this could happen. |
| final TypeBounds safeConvertBounds = TypeBounds.UNBOUNDED.notNarrowerThan(narrowestOperandType); |
| loadExpression(lhs, safeConvertBounds, baseAlreadyOnStack); |
| method.convert(operandBounds.within(method.peekType())); |
| loadExpression(rhs, safeConvertBounds, false); |
| method.convert(operandBounds.within(method.peekType())); |
| } else { |
| // Can reorder and move conversion into the operand. Combine load and convert into single operations. |
| loadExpression(lhs, operandBounds, baseAlreadyOnStack); |
| loadExpression(rhs, operandBounds, false); |
| } |
| } else { |
| // Can't reorder. Load and convert separately. |
| final TypeBounds safeConvertBounds = TypeBounds.UNBOUNDED.notNarrowerThan(narrowestOperandType); |
| loadExpression(lhs, safeConvertBounds, baseAlreadyOnStack); |
| final Type lhsLoadedType = method.peekType(); |
| loadExpression(rhs, safeConvertBounds, false); |
| final Type convertedLhsType = operandBounds.within(method.peekType()); |
| if (convertedLhsType != lhsLoadedType) { |
| // Do it conditionally, so that if conversion is a no-op we don't introduce a SWAP, SWAP. |
| method.swap().convert(convertedLhsType).swap(); |
| } |
| method.convert(operandBounds.within(method.peekType())); |
| } |
| assert Type.generic(method.peekType()) == operandBounds.narrowest; |
| assert Type.generic(method.peekType(1)) == operandBounds.narrowest; |
| |
| return method; |
| } |
| |
| /** |
| * Similar to {@link #loadBinaryOperands(BinaryNode)} but used specifically for loading operands of |
| * relational and equality comparison operators where at least one argument is non-object. (When both |
| * arguments are objects, we use {@link ScriptRuntime#EQ(Object, Object)}, {@link ScriptRuntime#LT(Object, Object)} |
| * etc. methods instead. Additionally, {@code ScriptRuntime} methods are used for strict (in)equality comparison |
| * of a boolean to anything that isn't a boolean.) This method handles the special case where one argument |
| * is an object and another is a primitive. Naively, these could also be delegated to {@code ScriptRuntime} methods |
| * by boxing the primitive. However, in all such cases the comparison is performed on numeric values, so it is |
| * possible to strength-reduce the operation by taking the number value of the object argument instead and |
| * comparing that to the primitive value ("primitive" will always be int, long, double, or boolean, and booleans |
| * compare as ints in these cases, so they're essentially numbers too). This method will emit code for loading |
| * arguments for such strength-reduced comparison. When both arguments are primitives, it just delegates to |
| * {@link #loadBinaryOperands(BinaryNode)}. |
| * |
| * @param cmp the comparison operation for which the operands need to be loaded on stack. |
| * @return the current method emitter. |
| */ |
| MethodEmitter loadComparisonOperands(final BinaryNode cmp) { |
| final Expression lhs = cmp.lhs(); |
| final Expression rhs = cmp.rhs(); |
| final Type lhsType = lhs.getType(); |
| final Type rhsType = rhs.getType(); |
| |
| // Only used when not both are object, for that we have ScriptRuntime.LT etc. |
| assert !(lhsType.isObject() && rhsType.isObject()); |
| |
| if (lhsType.isObject() || rhsType.isObject()) { |
| // We can reorder CONVERT LEFT and LOAD RIGHT only if either the left is a primitive, or the right |
| // is a local. This is more strict than loadBinaryNode reorder criteria, as it can allow JS primitive |
| // types too (notably: String is a JS primitive, but not a JVM primitive). We disallow String otherwise |
| // we would prematurely convert it to number when comparing to an optimistic expression, e.g. in |
| // "Hello" === String("Hello") the RHS starts out as an optimistic-int function call. If we allowed |
| // reordering, we'd end up with ToNumber("Hello") === {I%}String("Hello") that is obviously incorrect. |
| final boolean canReorder = lhsType.isPrimitive() || rhs.isLocal(); |
| // If reordering is allowed, and we're using a relational operator (that is, <, <=, >, >=) and not an |
| // (in)equality operator, then we encourage combining of LOAD and CONVERT into a single operation. |
| // This is because relational operators' semantics prescribes vanilla ToNumber() conversion, while |
| // (in)equality operators need the specialized JSType.toNumberFor[Strict]Equals. E.g. in the code snippet |
| // "i < obj.size" (where i is primitive and obj.size is statically an object), ".size" will thus be allowed |
| // to compile as: |
| // invokedynamic dyn:getProp|getElem|getMethod:size(Object;)D |
| // instead of the more costly: |
| // invokedynamic dyn:getProp|getElem|getMethod:size(Object;)Object |
| // invokestatic JSType.toNumber(Object)D |
| // Note also that even if this is allowed, we're only using it on operands that are non-optimistic, as |
| // otherwise the logic for determining effective optimistic-ness would turn an optimistic double return |
| // into a freely coercible one, which would be wrong. |
| final boolean canCombineLoadAndConvert = canReorder && cmp.isRelational(); |
| |
| // LOAD LEFT |
| loadExpression(lhs, canCombineLoadAndConvert && !lhs.isOptimistic() ? TypeBounds.NUMBER : TypeBounds.UNBOUNDED); |
| |
| final Type lhsLoadedType = method.peekType(); |
| final TokenType tt = cmp.tokenType(); |
| if (canReorder) { |
| // Can reorder CONVERT LEFT and LOAD RIGHT |
| emitObjectToNumberComparisonConversion(method, tt); |
| loadExpression(rhs, canCombineLoadAndConvert && !rhs.isOptimistic() ? TypeBounds.NUMBER : TypeBounds.UNBOUNDED); |
| } else { |
| // Can't reorder CONVERT LEFT and LOAD RIGHT |
| loadExpression(rhs, TypeBounds.UNBOUNDED); |
| if (lhsLoadedType != Type.NUMBER) { |
| method.swap(); |
| emitObjectToNumberComparisonConversion(method, tt); |
| method.swap(); |
| } |
| } |
| |
| // CONVERT RIGHT |
| emitObjectToNumberComparisonConversion(method, tt); |
| return method; |
| } |
| // For primitive operands, just don't do anything special. |
| return loadBinaryOperands(cmp); |
| } |
| |
| private static void emitObjectToNumberComparisonConversion(final MethodEmitter method, final TokenType tt) { |
| switch(tt) { |
| case EQ: |
| case NE: |
| if (method.peekType().isObject()) { |
| TO_NUMBER_FOR_EQ.invoke(method); |
| return; |
| } |
| break; |
| case EQ_STRICT: |
| case NE_STRICT: |
| if (method.peekType().isObject()) { |
| TO_NUMBER_FOR_STRICT_EQ.invoke(method); |
| return; |
| } |
| break; |
| default: |
| break; |
| } |
| method.convert(Type.NUMBER); |
| } |
| |
| private static Type undefinedToNumber(final Type type) { |
| return type == Type.UNDEFINED ? Type.NUMBER : type; |
| } |
| |
| private static final class TypeBounds { |
| final Type narrowest; |
| final Type widest; |
| |
| static final TypeBounds UNBOUNDED = new TypeBounds(Type.UNKNOWN, Type.OBJECT); |
| static final TypeBounds INT = exact(Type.INT); |
| static final TypeBounds NUMBER = exact(Type.NUMBER); |
| static final TypeBounds OBJECT = exact(Type.OBJECT); |
| static final TypeBounds BOOLEAN = exact(Type.BOOLEAN); |
| |
| static TypeBounds exact(final Type type) { |
| return new TypeBounds(type, type); |
| } |
| |
| TypeBounds(final Type narrowest, final Type widest) { |
| assert widest != null && widest != Type.UNDEFINED && widest != Type.UNKNOWN : widest; |
| assert narrowest != null && narrowest != Type.UNDEFINED : narrowest; |
| assert !narrowest.widerThan(widest) : narrowest + " wider than " + widest; |
| assert !widest.narrowerThan(narrowest); |
| this.narrowest = Type.generic(narrowest); |
| this.widest = Type.generic(widest); |
| } |
| |
| TypeBounds notNarrowerThan(final Type type) { |
| return maybeNew(Type.narrowest(Type.widest(narrowest, type), widest), widest); |
| } |
| |
| TypeBounds notWiderThan(final Type type) { |
| return maybeNew(Type.narrowest(narrowest, type), Type.narrowest(widest, type)); |
| } |
| |
| boolean canBeNarrowerThan(final Type type) { |
| return narrowest.narrowerThan(type); |
| } |
| |
| TypeBounds maybeNew(final Type newNarrowest, final Type newWidest) { |
| if(newNarrowest == narrowest && newWidest == widest) { |
| return this; |
| } |
| return new TypeBounds(newNarrowest, newWidest); |
| } |
| |
| TypeBounds booleanToInt() { |
| return maybeNew(CodeGenerator.booleanToInt(narrowest), CodeGenerator.booleanToInt(widest)); |
| } |
| |
| TypeBounds objectToNumber() { |
| return maybeNew(CodeGenerator.objectToNumber(narrowest), CodeGenerator.objectToNumber(widest)); |
| } |
| |
| Type within(final Type type) { |
| if(type.narrowerThan(narrowest)) { |
| return narrowest; |
| } |
| if(type.widerThan(widest)) { |
| return widest; |
| } |
| return type; |
| } |
| |
| @Override |
| public String toString() { |
| return "[" + narrowest + ", " + widest + "]"; |
| } |
| } |
| |
| private static Type booleanToInt(final Type t) { |
| return t == Type.BOOLEAN ? Type.INT : t; |
| } |
| |
| private static Type objectToNumber(final Type t) { |
| return t.isObject() ? Type.NUMBER : t; |
| } |
| |
| MethodEmitter loadExpressionAsType(final Expression expr, final Type type) { |
| if(type == Type.BOOLEAN) { |
| return loadExpressionAsBoolean(expr); |
| } else if(type == Type.UNDEFINED) { |
| assert expr.getType() == Type.UNDEFINED; |
| return loadExpressionAsObject(expr); |
| } |
| // having no upper bound preserves semantics of optimistic operations in the expression (by not having them |
| // converted early) and then applies explicit conversion afterwards. |
| return loadExpression(expr, TypeBounds.UNBOUNDED.notNarrowerThan(type)).convert(type); |
| } |
| |
| private MethodEmitter loadExpression(final Expression expr, final TypeBounds resultBounds) { |
| return loadExpression(expr, resultBounds, false); |
| } |
| |
| /** |
| * Emits code for evaluating an expression and leaving its value on top of the stack, narrowing or widening it if |
| * necessary. |
| * @param expr the expression to load |
| * @param resultBounds the incoming type bounds. The value on the top of the stack is guaranteed to not be of narrower |
| * type than the narrowest bound, or wider type than the widest bound after it is loaded. |
| * @param baseAlreadyOnStack true if the base of an access or index node is already on the stack. Used to avoid |
| * double evaluation of bases in self-assignment expressions to access and index nodes. {@code Type.OBJECT} is used |
| * to indicate the widest possible type. |
| * @return the method emitter |
| */ |
| private MethodEmitter loadExpression(final Expression expr, final TypeBounds resultBounds, final boolean baseAlreadyOnStack) { |
| |
| /* |
| * The load may be of type IdentNode, e.g. "x", AccessNode, e.g. "x.y" |
| * or IndexNode e.g. "x[y]". Both AccessNodes and IndexNodes are |
| * BaseNodes and the logic for loading the base object is reused |
| */ |
| final CodeGenerator codegen = this; |
| |
| final boolean isCurrentDiscard = codegen.lc.isCurrentDiscard(expr); |
| expr.accept(new NodeOperatorVisitor<LexicalContext>(new LexicalContext()) { |
| @Override |
| public boolean enterIdentNode(final IdentNode identNode) { |
| loadIdent(identNode, resultBounds); |
| return false; |
| } |
| |
| @Override |
| public boolean enterAccessNode(final AccessNode accessNode) { |
| new OptimisticOperation(accessNode, resultBounds) { |
| @Override |
| void loadStack() { |
| if (!baseAlreadyOnStack) { |
| loadExpressionAsObject(accessNode.getBase()); |
| } |
| assert method.peekType().isObject(); |
| } |
| @Override |
| void consumeStack() { |
| final int flags = getCallSiteFlags(); |
| dynamicGet(accessNode.getProperty(), flags, accessNode.isFunction(), accessNode.isIndex()); |
| } |
| }.emit(baseAlreadyOnStack ? 1 : 0); |
| return false; |
| } |
| |
| @Override |
| public boolean enterIndexNode(final IndexNode indexNode) { |
| new OptimisticOperation(indexNode, resultBounds) { |
| @Override |
| void loadStack() { |
| if (!baseAlreadyOnStack) { |
| loadExpressionAsObject(indexNode.getBase()); |
| loadExpressionUnbounded(indexNode.getIndex()); |
| } |
| } |
| @Override |
| void consumeStack() { |
| final int flags = getCallSiteFlags(); |
| dynamicGetIndex(flags, indexNode.isFunction()); |
| } |
| }.emit(baseAlreadyOnStack ? 2 : 0); |
| return false; |
| } |
| |
| @Override |
| public boolean enterFunctionNode(final FunctionNode functionNode) { |
| // function nodes will always leave a constructed function object on stack, no need to load the symbol |
| // separately as in enterDefault() |
| lc.pop(functionNode); |
| functionNode.accept(codegen); |
| // NOTE: functionNode.accept() will produce a different FunctionNode that we discard. This incidentally |
| // doesn't cause problems as we're never touching FunctionNode again after it's visited here - codegen |
| // is the last element in the compilation pipeline, the AST it produces is not used externally. So, we |
| // re-push the original functionNode. |
| lc.push(functionNode); |
| return false; |
| } |
| |
| @Override |
| public boolean enterASSIGN(final BinaryNode binaryNode) { |
| checkAssignTarget(binaryNode.lhs()); |
| loadASSIGN(binaryNode); |
| return false; |
| } |
| |
| @Override |
| public boolean enterASSIGN_ADD(final BinaryNode binaryNode) { |
| checkAssignTarget(binaryNode.lhs()); |
| loadASSIGN_ADD(binaryNode); |
| return false; |
| } |
| |
| @Override |
| public boolean enterASSIGN_BIT_AND(final BinaryNode binaryNode) { |
| checkAssignTarget(binaryNode.lhs()); |
| loadASSIGN_BIT_AND(binaryNode); |
| return false; |
| } |
| |
| @Override |
| public boolean enterASSIGN_BIT_OR(final BinaryNode binaryNode) { |
| checkAssignTarget(binaryNode.lhs()); |
| loadASSIGN_BIT_OR(binaryNode); |
| return false; |
| } |
| |
| @Override |
| public boolean enterASSIGN_BIT_XOR(final BinaryNode binaryNode) { |
| checkAssignTarget(binaryNode.lhs()); |
| loadASSIGN_BIT_XOR(binaryNode); |
| return false; |
| } |
| |
| @Override |
| public boolean enterASSIGN_DIV(final BinaryNode binaryNode) { |
| checkAssignTarget(binaryNode.lhs()); |
| loadASSIGN_DIV(binaryNode); |
| return false; |
| } |
| |
| @Override |
| public boolean enterASSIGN_MOD(final BinaryNode binaryNode) { |
| checkAssignTarget(binaryNode.lhs()); |
| loadASSIGN_MOD(binaryNode); |
| return false; |
| } |
| |
| @Override |
| public boolean enterASSIGN_MUL(final BinaryNode binaryNode) { |
| checkAssignTarget(binaryNode.lhs()); |
| loadASSIGN_MUL(binaryNode); |
| return false; |
| } |
| |
| @Override |
| public boolean enterASSIGN_SAR(final BinaryNode binaryNode) { |
| checkAssignTarget(binaryNode.lhs()); |
| loadASSIGN_SAR(binaryNode); |
| return false; |
| } |
| |
| @Override |
| public boolean enterASSIGN_SHL(final BinaryNode binaryNode) { |
| checkAssignTarget(binaryNode.lhs()); |
| loadASSIGN_SHL(binaryNode); |
| return false; |
| } |
| |
| @Override |
| public boolean enterASSIGN_SHR(final BinaryNode binaryNode) { |
| checkAssignTarget(binaryNode.lhs()); |
| loadASSIGN_SHR(binaryNode); |
| return false; |
| } |
| |
| @Override |
| public boolean enterASSIGN_SUB(final BinaryNode binaryNode) { |
| checkAssignTarget(binaryNode.lhs()); |
| loadASSIGN_SUB(binaryNode); |
| return false; |
| } |
| |
| @Override |
| public boolean enterCallNode(final CallNode callNode) { |
| return loadCallNode(callNode, resultBounds); |
| } |
| |
| @Override |
| public boolean enterLiteralNode(final LiteralNode<?> literalNode) { |
| loadLiteral(literalNode, resultBounds); |
| return false; |
| } |
| |
| @Override |
| public boolean enterTernaryNode(final TernaryNode ternaryNode) { |
| loadTernaryNode(ternaryNode, resultBounds); |
| return false; |
| } |
| |
| @Override |
| public boolean enterADD(final BinaryNode binaryNode) { |
| loadADD(binaryNode, resultBounds); |
| return false; |
| } |
| |
| @Override |
| public boolean enterSUB(final UnaryNode unaryNode) { |
| loadSUB(unaryNode, resultBounds); |
| return false; |
| } |
| |
| @Override |
| public boolean enterSUB(final BinaryNode binaryNode) { |
| loadSUB(binaryNode, resultBounds); |
| return false; |
| } |
| |
| @Override |
| public boolean enterMUL(final BinaryNode binaryNode) { |
| loadMUL(binaryNode, resultBounds); |
| return false; |
| } |
| |
| @Override |
| public boolean enterDIV(final BinaryNode binaryNode) { |
| loadDIV(binaryNode, resultBounds); |
| return false; |
| } |
| |
| @Override |
| public boolean enterMOD(final BinaryNode binaryNode) { |
| loadMOD(binaryNode, resultBounds); |
| return false; |
| } |
| |
| @Override |
| public boolean enterSAR(final BinaryNode binaryNode) { |
| loadSAR(binaryNode); |
| return false; |
| } |
| |
| @Override |
| public boolean enterSHL(final BinaryNode binaryNode) { |
| loadSHL(binaryNode); |
| return false; |
| } |
| |
| @Override |
| public boolean enterSHR(final BinaryNode binaryNode) { |
| loadSHR(binaryNode); |
| return false; |
| } |
| |
| @Override |
| public boolean enterCOMMALEFT(final BinaryNode binaryNode) { |
| loadCOMMALEFT(binaryNode, resultBounds); |
| return false; |
| } |
| |
| @Override |
| public boolean enterCOMMARIGHT(final BinaryNode binaryNode) { |
| loadCOMMARIGHT(binaryNode, resultBounds); |
| return false; |
| } |
| |
| @Override |
| public boolean enterAND(final BinaryNode binaryNode) { |
| loadAND_OR(binaryNode, resultBounds, true); |
| return false; |
| } |
| |
| @Override |
| public boolean enterOR(final BinaryNode binaryNode) { |
| loadAND_OR(binaryNode, resultBounds, false); |
| return false; |
| } |
| |
| @Override |
| public boolean enterNOT(final UnaryNode unaryNode) { |
| loadNOT(unaryNode); |
| return false; |
| } |
| |
| @Override |
| public boolean enterADD(final UnaryNode unaryNode) { |
| loadADD(unaryNode, resultBounds); |
| return false; |
| } |
| |
| @Override |
| public boolean enterBIT_NOT(final UnaryNode unaryNode) { |
| loadBIT_NOT(unaryNode); |
| return false; |
| } |
| |
| @Override |
| public boolean enterBIT_AND(final BinaryNode binaryNode) { |
| loadBIT_AND(binaryNode); |
| return false; |
| } |
| |
| @Override |
| public boolean enterBIT_OR(final BinaryNode binaryNode) { |
| loadBIT_OR(binaryNode); |
| return false; |
| } |
| |
| @Override |
| public boolean enterBIT_XOR(final BinaryNode binaryNode) { |
| loadBIT_XOR(binaryNode); |
| return false; |
| } |
| |
| @Override |
| public boolean enterVOID(final UnaryNode unaryNode) { |
| loadVOID(unaryNode, resultBounds); |
| return false; |
| } |
| |
| @Override |
| public boolean enterEQ(final BinaryNode binaryNode) { |
| loadCmp(binaryNode, Condition.EQ); |
| return false; |
| } |
| |
| @Override |
| public boolean enterEQ_STRICT(final BinaryNode binaryNode) { |
| loadCmp(binaryNode, Condition.EQ); |
| return false; |
| } |
| |
| @Override |
| public boolean enterGE(final BinaryNode binaryNode) { |
| loadCmp(binaryNode, Condition.GE); |
| return false; |
| } |
| |
| @Override |
| public boolean enterGT(final BinaryNode binaryNode) { |
| loadCmp(binaryNode, Condition.GT); |
| return false; |
| } |
| |
| @Override |
| public boolean enterLE(final BinaryNode binaryNode) { |
| loadCmp(binaryNode, Condition.LE); |
| return false; |
| } |
| |
| @Override |
| public boolean enterLT(final BinaryNode binaryNode) { |
| loadCmp(binaryNode, Condition.LT); |
| return false; |
| } |
| |
| @Override |
| public boolean enterNE(final BinaryNode binaryNode) { |
| loadCmp(binaryNode, Condition.NE); |
| return false; |
| } |
| |
| @Override |
| public boolean enterNE_STRICT(final BinaryNode binaryNode) { |
| loadCmp(binaryNode, Condition.NE); |
| return false; |
| } |
| |
| @Override |
| public boolean enterObjectNode(final ObjectNode objectNode) { |
| loadObjectNode(objectNode); |
| return false; |
| } |
| |
| @Override |
| public boolean enterRuntimeNode(final RuntimeNode runtimeNode) { |
| loadRuntimeNode(runtimeNode); |
| return false; |
| } |
| |
| @Override |
| public boolean enterNEW(final UnaryNode unaryNode) { |
| loadNEW(unaryNode); |
| return false; |
| } |
| |
| @Override |
| public boolean enterDECINC(final UnaryNode unaryNode) { |
| checkAssignTarget(unaryNode.getExpression()); |
| loadDECINC(unaryNode); |
| return false; |
| } |
| |
| @Override |
| public boolean enterJoinPredecessorExpression(final JoinPredecessorExpression joinExpr) { |
| loadMaybeDiscard(joinExpr, joinExpr.getExpression(), resultBounds); |
| return false; |
| } |
| |
| @Override |
| public boolean enterGetSplitState(final GetSplitState getSplitState) { |
| method.loadScope(); |
| method.invoke(Scope.GET_SPLIT_STATE); |
| return false; |
| } |
| |
| @Override |
| public boolean enterDefault(final Node otherNode) { |
| // Must have handled all expressions that can legally be encountered. |
| throw new AssertionError(otherNode.getClass().getName()); |
| } |
| }); |
| if(!isCurrentDiscard) { |
| coerceStackTop(resultBounds); |
| } |
| return method; |
| } |
| |
| private MethodEmitter coerceStackTop(final TypeBounds typeBounds) { |
| return method.convert(typeBounds.within(method.peekType())); |
| } |
| |
| /** |
| * Closes any still open entries for this block's local variables in the bytecode local variable table. |
| * |
| * @param block block containing symbols. |
| */ |
| private void closeBlockVariables(final Block block) { |
| for (final Symbol symbol : block.getSymbols()) { |
| if (symbol.isBytecodeLocal()) { |
| method.closeLocalVariable(symbol, block.getBreakLabel()); |
| } |
| } |
| } |
| |
| @Override |
| public boolean enterBlock(final Block block) { |
| final Label entryLabel = block.getEntryLabel(); |
| if (entryLabel.isBreakTarget()) { |
| // Entry label is a break target only for an inlined finally block. |
| assert !method.isReachable(); |
| method.breakLabel(entryLabel, lc.getUsedSlotCount()); |
| } else { |
| method.label(entryLabel); |
| } |
| if(!method.isReachable()) { |
| return false; |
| } |
| if(lc.isFunctionBody() && emittedMethods.contains(lc.getCurrentFunction().getName())) { |
| return false; |
| } |
| initLocals(block); |
| |
| assert lc.getUsedSlotCount() == method.getFirstTemp(); |
| return true; |
| } |
| |
| boolean useOptimisticTypes() { |
| return !lc.inSplitNode() && compiler.useOptimisticTypes(); |
| } |
| |
| @Override |
| public Node leaveBlock(final Block block) { |
| popBlockScope(block); |
| method.beforeJoinPoint(block); |
| |
| closeBlockVariables(block); |
| lc.releaseSlots(); |
| assert !method.isReachable() || (lc.isFunctionBody() ? 0 : lc.getUsedSlotCount()) == method.getFirstTemp() : |
| "reachable="+method.isReachable() + |
| " isFunctionBody=" + lc.isFunctionBody() + |
| " usedSlotCount=" + lc.getUsedSlotCount() + |
| " firstTemp=" + method.getFirstTemp(); |
| |
| return block; |
| } |
| |
| private void popBlockScope(final Block block) { |
| final Label breakLabel = block.getBreakLabel(); |
| |
| if(!block.needsScope() || lc.isFunctionBody()) { |
| emitBlockBreakLabel(breakLabel); |
| return; |
| } |
| |
| final Label beginTryLabel = scopeEntryLabels.pop(); |
| final Label recoveryLabel = new Label("block_popscope_catch"); |
| emitBlockBreakLabel(breakLabel); |
| final boolean bodyCanThrow = breakLabel.isAfter(beginTryLabel); |
| if(bodyCanThrow) { |
| method._try(beginTryLabel, breakLabel, recoveryLabel); |
| } |
| |
| Label afterCatchLabel = null; |
| |
| if(method.isReachable()) { |
| popScope(); |
| if(bodyCanThrow) { |
| afterCatchLabel = new Label("block_after_catch"); |
| method._goto(afterCatchLabel); |
| } |
| } |
| |
| if(bodyCanThrow) { |
| assert !method.isReachable(); |
| method._catch(recoveryLabel); |
| popScopeException(); |
| method.athrow(); |
| } |
| if(afterCatchLabel != null) { |
| method.label(afterCatchLabel); |
| } |
| } |
| |
| private void emitBlockBreakLabel(final Label breakLabel) { |
| // TODO: this is totally backwards. Block should not be breakable, LabelNode should be breakable. |
| final LabelNode labelNode = lc.getCurrentBlockLabelNode(); |
| if(labelNode != null) { |
| // Only have conversions if we're reachable |
| assert labelNode.getLocalVariableConversion() == null || method.isReachable(); |
| method.beforeJoinPoint(labelNode); |
| method.breakLabel(breakLabel, labeledBlockBreakLiveLocals.pop()); |
| } else { |
| method.label(breakLabel); |
| } |
| } |
| |
| private void popScope() { |
| popScopes(1); |
| } |
| |
| /** |
| * Pop scope as part of an exception handler. Similar to {@code popScope()} but also takes care of adjusting the |
| * number of scopes that needs to be popped in case a rest-of continuation handler encounters an exception while |
| * performing a ToPrimitive conversion. |
| */ |
| private void popScopeException() { |
| popScope(); |
| final ContinuationInfo ci = getContinuationInfo(); |
| if(ci != null) { |
| final Label catchLabel = ci.catchLabel; |
| if(catchLabel != METHOD_BOUNDARY && catchLabel == catchLabels.peek()) { |
| ++ci.exceptionScopePops; |
| } |
| } |
| } |
| |
| private void popScopesUntil(final LexicalContextNode until) { |
| popScopes(lc.getScopeNestingLevelTo(until)); |
| } |
| |
| private void popScopes(final int count) { |
| if(count == 0) { |
| return; |
| } |
| assert count > 0; // together with count == 0 check, asserts nonnegative count |
| if (!method.hasScope()) { |
| // We can sometimes invoke this method even if the method has no slot for the scope object. Typical example: |
| // for(;;) { with({}) { break; } }. WithNode normally creates a scope, but if it uses no identifiers and |
| // nothing else forces creation of a scope in the method, we just won't have the :scope local variable. |
| return; |
| } |
| method.loadCompilerConstant(SCOPE); |
| for(int i = 0; i < count; ++i) { |
| method.invoke(ScriptObject.GET_PROTO); |
| } |
| method.storeCompilerConstant(SCOPE); |
| } |
| |
| @Override |
| public boolean enterBreakNode(final BreakNode breakNode) { |
| return enterJumpStatement(breakNode); |
| } |
| |
| @Override |
| public boolean enterJumpToInlinedFinally(final JumpToInlinedFinally jumpToInlinedFinally) { |
| return enterJumpStatement(jumpToInlinedFinally); |
| } |
| |
| private boolean enterJumpStatement(final JumpStatement jump) { |
| if(!method.isReachable()) { |
| return false; |
| } |
| enterStatement(jump); |
| |
| method.beforeJoinPoint(jump); |
| popScopesUntil(jump.getPopScopeLimit(lc)); |
| final Label targetLabel = jump.getTargetLabel(lc); |
| targetLabel.markAsBreakTarget(); |
| method._goto(targetLabel); |
| |
| return false; |
| } |
| |
| private int loadArgs(final List<Expression> args) { |
| final int argCount = args.size(); |
| // arg have already been converted to objects here. |
| if (argCount > LinkerCallSite.ARGLIMIT) { |
| loadArgsArray(args); |
| return 1; |
| } |
| |
| for (final Expression arg : args) { |
| assert arg != null; |
| loadExpressionUnbounded(arg); |
| } |
| return argCount; |
| } |
| |
| private boolean loadCallNode(final CallNode callNode, final TypeBounds resultBounds) { |
| lineNumber(callNode.getLineNumber()); |
| |
| final List<Expression> args = callNode.getArgs(); |
| final Expression function = callNode.getFunction(); |
| final Block currentBlock = lc.getCurrentBlock(); |
| final CodeGeneratorLexicalContext codegenLexicalContext = lc; |
| |
| function.accept(new SimpleNodeVisitor() { |
| private MethodEmitter sharedScopeCall(final IdentNode identNode, final int flags) { |
| final Symbol symbol = identNode.getSymbol(); |
| final boolean isFastScope = isFastScope(symbol); |
| new OptimisticOperation(callNode, resultBounds) { |
| @Override |
| void loadStack() { |
| method.loadCompilerConstant(SCOPE); |
| if (isFastScope) { |
| method.load(getScopeProtoDepth(currentBlock, symbol)); |
| } else { |
| method.load(-1); // Bypass fast-scope code in shared callsite |
| } |
| loadArgs(args); |
| } |
| @Override |
| void consumeStack() { |
| final Type[] paramTypes = method.getTypesFromStack(args.size()); |
| // We have trouble finding e.g. in Type.typeFor(asm.Type) because it can't see the Context class |
| // loader, so we need to weaken reference signatures to Object. |
| for(int i = 0; i < paramTypes.length; ++i) { |
| paramTypes[i] = Type.generic(paramTypes[i]); |
| } |
| // As shared scope calls are only used in non-optimistic compilation, we switch from using |
| // TypeBounds to just a single definitive type, resultBounds.widest. |
| final SharedScopeCall scopeCall = codegenLexicalContext.getScopeCall(unit, symbol, |
| identNode.getType(), resultBounds.widest, paramTypes, flags); |
| scopeCall.generateInvoke(method); |
| } |
| }.emit(); |
| return method; |
| } |
| |
| private void scopeCall(final IdentNode ident, final int flags) { |
| new OptimisticOperation(callNode, resultBounds) { |
| int argsCount; |
| @Override |
| void loadStack() { |
| loadExpressionAsObject(ident); // foo() makes no sense if foo == 3 |
| // ScriptFunction will see CALLSITE_SCOPE and will bind scope accordingly. |
| method.loadUndefined(Type.OBJECT); //the 'this' |
| argsCount = loadArgs(args); |
| } |
| @Override |
| void consumeStack() { |
| dynamicCall(2 + argsCount, flags, ident.getName()); |
| } |
| }.emit(); |
| } |
| |
| private void evalCall(final IdentNode ident, final int flags) { |
| final Label invoke_direct_eval = new Label("invoke_direct_eval"); |
| final Label is_not_eval = new Label("is_not_eval"); |
| final Label eval_done = new Label("eval_done"); |
| |
| new OptimisticOperation(callNode, resultBounds) { |
| int argsCount; |
| @Override |
| void loadStack() { |
| /* |
| * We want to load 'eval' to check if it is indeed global builtin eval. |
| * If this eval call is inside a 'with' statement, dyn:getMethod|getProp|getElem |
| * would be generated if ident is a "isFunction". But, that would result in a |
| * bound function from WithObject. We don't want that as bound function as that |
| * won't be detected as builtin eval. So, we make ident as "not a function" which |
| * results in "dyn:getProp|getElem|getMethod" being generated and so WithObject |
| * would return unbounded eval function. |
| * |
| * Example: |
| * |
| * var global = this; |
| * function func() { |
| * with({ eval: global.eval) { eval("var x = 10;") } |
| * } |
| */ |
| loadExpressionAsObject(ident.setIsNotFunction()); // Type.OBJECT as foo() makes no sense if foo == 3 |
| globalIsEval(); |
| method.ifeq(is_not_eval); |
| |
| // Load up self (scope). |
| method.loadCompilerConstant(SCOPE); |
| final List<Expression> evalArgs = callNode.getEvalArgs().getArgs(); |
| // load evaluated code |
| loadExpressionAsObject(evalArgs.get(0)); |
| // load second and subsequent args for side-effect |
| final int numArgs = evalArgs.size(); |
| for (int i = 1; i < numArgs; i++) { |
| loadAndDiscard(evalArgs.get(i)); |
| } |
| method._goto(invoke_direct_eval); |
| |
| method.label(is_not_eval); |
| // load this time but with dyn:getMethod|getProp|getElem |
| loadExpressionAsObject(ident); // Type.OBJECT as foo() makes no sense if foo == 3 |
| // This is some scope 'eval' or global eval replaced by user |
| // but not the built-in ECMAScript 'eval' function call |
| method.loadNull(); |
| argsCount = loadArgs(callNode.getArgs()); |
| } |
| |
| @Override |
| void consumeStack() { |
| // Ordinary call |
| dynamicCall(2 + argsCount, flags, "eval"); |
| method._goto(eval_done); |
| |
| method.label(invoke_direct_eval); |
| // Special/extra 'eval' arguments. These can be loaded late (in consumeStack) as we know none of |
| // them can ever be optimistic. |
| method.loadCompilerConstant(THIS); |
| method.load(callNode.getEvalArgs().getLocation()); |
| method.load(CodeGenerator.this.lc.getCurrentFunction().isStrict()); |
| // direct call to Global.directEval |
| globalDirectEval(); |
| convertOptimisticReturnValue(); |
| coerceStackTop(resultBounds); |
| } |
| }.emit(); |
| |
| method.label(eval_done); |
| } |
| |
| @Override |
| public boolean enterIdentNode(final IdentNode node) { |
| final Symbol symbol = node.getSymbol(); |
| |
| if (symbol.isScope()) { |
| final int flags = getScopeCallSiteFlags(symbol); |
| final int useCount = symbol.getUseCount(); |
| |
| // Threshold for generating shared scope callsite is lower for fast scope symbols because we know |
| // we can dial in the correct scope. However, we also need to enable it for non-fast scopes to |
| // support huge scripts like mandreel.js. |
| if (callNode.isEval()) { |
| evalCall(node, flags); |
| } else if (useCount <= SharedScopeCall.FAST_SCOPE_CALL_THRESHOLD |
| || !isFastScope(symbol) && useCount <= SharedScopeCall.SLOW_SCOPE_CALL_THRESHOLD |
| || CodeGenerator.this.lc.inDynamicScope() |
| || callNode.isOptimistic()) { |
| scopeCall(node, flags); |
| } else { |
| sharedScopeCall(node, flags); |
| } |
| assert method.peekType().equals(resultBounds.within(callNode.getType())) : method.peekType() + " != " + resultBounds + "(" + callNode.getType() + ")"; |
| } else { |
| enterDefault(node); |
| } |
| |
| return false; |
| } |
| |
| @Override |
| public boolean enterAccessNode(final AccessNode node) { |
| //check if this is an apply to call node. only real applies, that haven't been |
| //shadowed from their way to the global scope counts |
| |
| //call nodes have program points. |
| |
| final int flags = getCallSiteFlags() | (callNode.isApplyToCall() ? CALLSITE_APPLY_TO_CALL : 0); |
| |
| new OptimisticOperation(callNode, resultBounds) { |
| int argCount; |
| @Override |
| void loadStack() { |
| loadExpressionAsObject(node.getBase()); |
| method.dup(); |
| // NOTE: not using a nested OptimisticOperation on this dynamicGet, as we expect to get back |
| // a callable object. Nobody in their right mind would optimistically type this call site. |
| assert !node.isOptimistic(); |
| method.dynamicGet(node.getType(), node.getProperty(), flags, true, node.isIndex()); |
| method.swap(); |
| argCount = loadArgs(args); |
| } |
| @Override |
| void consumeStack() { |
| dynamicCall(2 + argCount, flags, node.toString(false)); |
| } |
| }.emit(); |
| |
| return false; |
| } |
| |
| @Override |
| public boolean enterFunctionNode(final FunctionNode origCallee) { |
| new OptimisticOperation(callNode, resultBounds) { |
| FunctionNode callee; |
| int argsCount; |
| @Override |
| void loadStack() { |
| callee = (FunctionNode)origCallee.accept(CodeGenerator.this); |
| if (callee.isStrict()) { // "this" is undefined |
| method.loadUndefined(Type.OBJECT); |
| } else { // get global from scope (which is the self) |
| globalInstance(); |
| } |
| argsCount = loadArgs(args); |
| } |
| |
| @Override |
| void consumeStack() { |
| dynamicCall(2 + argsCount, getCallSiteFlags(), null); |
| } |
| }.emit(); |
| return false; |
| } |
| |
| @Override |
| public boolean enterIndexNode(final IndexNode node) { |
| new OptimisticOperation(callNode, resultBounds) { |
| int argsCount; |
| @Override |
| void loadStack() { |
| loadExpressionAsObject(node.getBase()); |
| method.dup(); |
| final Type indexType = node.getIndex().getType(); |
| if (indexType.isObject() || indexType.isBoolean()) { |
| loadExpressionAsObject(node.getIndex()); //TODO boolean |
| } else { |
| loadExpressionUnbounded(node.getIndex()); |
| } |
| // NOTE: not using a nested OptimisticOperation on this dynamicGetIndex, as we expect to get |
| // back a callable object. Nobody in their right mind would optimistically type this call site. |
| assert !node.isOptimistic(); |
| method.dynamicGetIndex(node.getType(), getCallSiteFlags(), true); |
| method.swap(); |
| argsCount = loadArgs(args); |
| } |
| @Override |
| void consumeStack() { |
| dynamicCall(2 + argsCount, getCallSiteFlags(), node.toString(false)); |
| } |
| }.emit(); |
| return false; |
| } |
| |
| @Override |
| protected boolean enterDefault(final Node node) { |
| new OptimisticOperation(callNode, resultBounds) { |
| int argsCount; |
| @Override |
| void loadStack() { |
| // Load up function. |
| loadExpressionAsObject(function); //TODO, e.g. booleans can be used as functions |
| method.loadUndefined(Type.OBJECT); // ScriptFunction will figure out the correct this when it sees CALLSITE_SCOPE |
| argsCount = loadArgs(args); |
| } |
| @Override |
| void consumeStack() { |
| final int flags = getCallSiteFlags() | CALLSITE_SCOPE; |
| dynamicCall(2 + argsCount, flags, node.toString(false)); |
| } |
| }.emit(); |
| return false; |
| } |
| }); |
| |
| return false; |
| } |
| |
| /** |
| * Returns the flags with optimistic flag and program point removed. |
| * @param flags the flags that need optimism stripped from them. |
| * @return flags without optimism |
| */ |
| static int nonOptimisticFlags(final int flags) { |
| return flags & ~(CALLSITE_OPTIMISTIC | -1 << CALLSITE_PROGRAM_POINT_SHIFT); |
| } |
| |
| @Override |
| public boolean enterContinueNode(final ContinueNode continueNode) { |
| return enterJumpStatement(continueNode); |
| } |
| |
| @Override |
| public boolean enterEmptyNode(final EmptyNode emptyNode) { |
| // Don't even record the line number, it's irrelevant as there's no code. |
| return false; |
| } |
| |
| @Override |
| public boolean enterExpressionStatement(final ExpressionStatement expressionStatement) { |
| if(!method.isReachable()) { |
| return false; |
| } |
| enterStatement(expressionStatement); |
| |
| loadAndDiscard(expressionStatement.getExpression()); |
| assert method.getStackSize() == 0; |
| |
| return false; |
| } |
| |
| @Override |
| public boolean enterBlockStatement(final BlockStatement blockStatement) { |
| if(!method.isReachable()) { |
| return false; |
| } |
| enterStatement(blockStatement); |
| |
| blockStatement.getBlock().accept(this); |
| |
| return false; |
| } |
| |
| @Override |
| public boolean enterForNode(final ForNode forNode) { |
| if(!method.isReachable()) { |
| return false; |
| } |
| enterStatement(forNode); |
| if (forNode.isForIn()) { |
| enterForIn(forNode); |
| } else { |
| final Expression init = forNode.getInit(); |
| if (init != null) { |
| loadAndDiscard(init); |
| } |
| enterForOrWhile(forNode, forNode.getModify()); |
| } |
| |
| return false; |
| } |
| |
| private void enterForIn(final ForNode forNode) { |
| loadExpression(forNode.getModify(), TypeBounds.OBJECT); |
| method.invoke(forNode.isForEach() ? ScriptRuntime.TO_VALUE_ITERATOR : ScriptRuntime.TO_PROPERTY_ITERATOR); |
| final Symbol iterSymbol = forNode.getIterator(); |
| final int iterSlot = iterSymbol.getSlot(Type.OBJECT); |
| method.store(iterSymbol, ITERATOR_TYPE); |
| |
| method.beforeJoinPoint(forNode); |
| |
| final Label continueLabel = forNode.getContinueLabel(); |
| final Label breakLabel = forNode.getBreakLabel(); |
| |
| method.label(continueLabel); |
| method.load(ITERATOR_TYPE, iterSlot); |
| method.invoke(interfaceCallNoLookup(ITERATOR_CLASS, "hasNext", boolean.class)); |
| final JoinPredecessorExpression test = forNode.getTest(); |
| final Block body = forNode.getBody(); |
| if(LocalVariableConversion.hasLiveConversion(test)) { |
| final Label afterConversion = new Label("for_in_after_test_conv"); |
| method.ifne(afterConversion); |
| method.beforeJoinPoint(test); |
| method._goto(breakLabel); |
| method.label(afterConversion); |
| } else { |
| method.ifeq(breakLabel); |
| } |
| |
| new Store<Expression>(forNode.getInit()) { |
| @Override |
| protected void storeNonDiscard() { |
| // This expression is neither part of a discard, nor needs to be left on the stack after it was |
| // stored, so we override storeNonDiscard to be a no-op. |
| } |
| |
| @Override |
| protected void evaluate() { |
| new OptimisticOperation((Optimistic)forNode.getInit(), TypeBounds.UNBOUNDED) { |
| @Override |
| void loadStack() { |
| method.load(ITERATOR_TYPE, iterSlot); |
| } |
| |
| @Override |
| void consumeStack() { |
| method.invoke(interfaceCallNoLookup(ITERATOR_CLASS, "next", Object.class)); |
| convertOptimisticReturnValue(); |
| } |
| }.emit(); |
| } |
| }.store(); |
| body.accept(this); |
| |
| if(method.isReachable()) { |
| method._goto(continueLabel); |
| } |
| method.label(breakLabel); |
| } |
| |
| /** |
| * Initialize the slots in a frame to undefined. |
| * |
| * @param block block with local vars. |
| */ |
| private void initLocals(final Block block) { |
| lc.onEnterBlock(block); |
| |
| final boolean isFunctionBody = lc.isFunctionBody(); |
| final FunctionNode function = lc.getCurrentFunction(); |
| if (isFunctionBody) { |
| initializeMethodParameters(function); |
| if(!function.isVarArg()) { |
| expandParameterSlots(function); |
| } |
| if (method.hasScope()) { |
| if (function.needsParentScope()) { |
| method.loadCompilerConstant(CALLEE); |
| method.invoke(ScriptFunction.GET_SCOPE); |
| } else { |
| assert function.hasScopeBlock(); |
| method.loadNull(); |
| } |
| method.storeCompilerConstant(SCOPE); |
| } |
| if (function.needsArguments()) { |
| initArguments(function); |
| } |
| } |
| |
| /* |
| * Determine if block needs scope, if not, just do initSymbols for this block. |
| */ |
| if (block.needsScope()) { |
| /* |
| * Determine if function is varargs and consequently variables have to |
| * be in the scope. |
| */ |
| final boolean varsInScope = function.allVarsInScope(); |
| |
| // TODO for LET we can do better: if *block* does not contain any eval/with, we don't need its vars in scope. |
| |
| final boolean hasArguments = function.needsArguments(); |
| final List<MapTuple<Symbol>> tuples = new ArrayList<>(); |
| final Iterator<IdentNode> paramIter = function.getParameters().iterator(); |
| for (final Symbol symbol : block.getSymbols()) { |
| if (symbol.isInternal() || symbol.isThis()) { |
| continue; |
| } |
| |
| if (symbol.isVar()) { |
| assert !varsInScope || symbol.isScope(); |
| if (varsInScope || symbol.isScope()) { |
| assert symbol.isScope() : "scope for " + symbol + " should have been set in Lower already " + function.getName(); |
| assert !symbol.hasSlot() : "slot for " + symbol + " should have been removed in Lower already" + function.getName(); |
| |
| //this tuple will not be put fielded, as it has no value, just a symbol |
| tuples.add(new MapTuple<Symbol>(symbol.getName(), symbol, null)); |
| } else { |
| assert symbol.hasSlot() || symbol.slotCount() == 0 : symbol + " should have a slot only, no scope"; |
| } |
| } else if (symbol.isParam() && (varsInScope || hasArguments || symbol.isScope())) { |
| assert symbol.isScope() : "scope for " + symbol + " should have been set in AssignSymbols already " + function.getName() + " varsInScope="+varsInScope+" hasArguments="+hasArguments+" symbol.isScope()=" + symbol.isScope(); |
| assert !(hasArguments && symbol.hasSlot()) : "slot for " + symbol + " should have been removed in Lower already " + function.getName(); |
| |
| final Type paramType; |
| final Symbol paramSymbol; |
| |
| if (hasArguments) { |
| assert !symbol.hasSlot() : "slot for " + symbol + " should have been removed in Lower already "; |
| paramSymbol = null; |
| paramType = null; |
| } else { |
| paramSymbol = symbol; |
| // NOTE: We're relying on the fact here that Block.symbols is a LinkedHashMap, hence it will |
| // return symbols in the order they were defined, and parameters are defined in the same order |
| // they appear in the function. That's why we can have a single pass over the parameter list |
| // with an iterator, always just scanning forward for the next parameter that matches the symbol |
| // name. |
| for(;;) { |
| final IdentNode nextParam = paramIter.next(); |
| if(nextParam.getName().equals(symbol.getName())) { |
| paramType = nextParam.getType(); |
| break; |
| } |
| } |
| } |
| |
| tuples.add(new MapTuple<Symbol>(symbol.getName(), symbol, paramType, paramSymbol) { |
| //this symbol will be put fielded, we can't initialize it as undefined with a known type |
| @Override |
| public Class<?> getValueType() { |
| if (!useDualFields() || value == null || paramType == null || paramType.isBoolean()) { |
| return Object.class; |
| } |
| return paramType.getTypeClass(); |
| } |
| }); |
| } |
| } |
| |
| /* |
| * Create a new object based on the symbols and values, generate |
| * bootstrap code for object |
| */ |
| new FieldObjectCreator<Symbol>(this, tuples, true, hasArguments) { |
| @Override |
| protected void loadValue(final Symbol value, final Type type) { |
| method.load(value, type); |
| } |
| }.makeObject(method); |
| // program function: merge scope into global |
| if (isFunctionBody && function.isProgram()) { |
| method.invoke(ScriptRuntime.MERGE_SCOPE); |
| } |
| |
| method.storeCompilerConstant(SCOPE); |
| if(!isFunctionBody) { |
| // Function body doesn't need a try/catch to restore scope, as it'd be a dead store anyway. Allowing it |
| // actually causes issues with UnwarrantedOptimismException handlers as ASM will sort this handler to |
| // the top of the exception handler table, so it'll be triggered instead of the UOE handlers. |
| final Label scopeEntryLabel = new Label("scope_entry"); |
| scopeEntryLabels.push(scopeEntryLabel); |
| method.label(scopeEntryLabel); |
| } |
| } else if (isFunctionBody && function.isVarArg()) { |
| // Since we don't have a scope, parameters didn't get assigned array indices by the FieldObjectCreator, so |
| // we need to assign them separately here. |
| int nextParam = 0; |
| for (final IdentNode param : function.getParameters()) { |
| param.getSymbol().setFieldIndex(nextParam++); |
| } |
| } |
| |
| // Debugging: print symbols? @see --print-symbols flag |
| printSymbols(block, function, (isFunctionBody ? "Function " : "Block in ") + (function.getIdent() == null ? "<anonymous>" : function.getIdent().getName())); |
| } |
| |
| /** |
| * Incoming method parameters are always declared on method entry; declare them in the local variable table. |
| * @param function function for which code is being generated. |
| */ |
| private void initializeMethodParameters(final FunctionNode function) { |
| final Label functionStart = new Label("fn_start"); |
| method.label(functionStart); |
| int nextSlot = 0; |
| if(function.needsCallee()) { |
| initializeInternalFunctionParameter(CALLEE, function, functionStart, nextSlot++); |
| } |
| initializeInternalFunctionParameter(THIS, function, functionStart, nextSlot++); |
| if(function.isVarArg()) { |
| initializeInternalFunctionParameter(VARARGS, function, functionStart, nextSlot++); |
| } else { |
| for(final IdentNode param: function.getParameters()) { |
| final Symbol symbol = param.getSymbol(); |
| if(symbol.isBytecodeLocal()) { |
| method.initializeMethodParameter(symbol, param.getType(), functionStart); |
| } |
| } |
| } |
| } |
| |
| private void initializeInternalFunctionParameter(final CompilerConstants cc, final FunctionNode fn, final Label functionStart, final int slot) { |
| final Symbol symbol = initializeInternalFunctionOrSplitParameter(cc, fn, functionStart, slot); |
| // Internal function params (:callee, this, and :varargs) are never expanded to multiple slots |
| assert symbol.getFirstSlot() == slot; |
| } |
| |
| private Symbol initializeInternalFunctionOrSplitParameter(final CompilerConstants cc, final FunctionNode fn, final Label functionStart, final int slot) { |
| final Symbol symbol = fn.getBody().getExistingSymbol(cc.symbolName()); |
| final Type type = Type.typeFor(cc.type()); |
| method.initializeMethodParameter(symbol, type, functionStart); |
| method.onLocalStore(type, slot); |
| return symbol; |
| } |
| |
| /** |
| * Parameters come into the method packed into local variable slots next to each other. Nashorn on the other hand |
| * can use 1-6 slots for a local variable depending on all the types it needs to store. When this method is invoked, |
| * the symbols are already allocated such wider slots, but the values are still in tightly packed incoming slots, |
| * and we need to spread them into their new locations. |
| * @param function the function for which parameter-spreading code needs to be emitted |
| */ |
| private void expandParameterSlots(final FunctionNode function) { |
| final List<IdentNode> parameters = function.getParameters(); |
| // Calculate the total number of incoming parameter slots |
| int currentIncomingSlot = function.needsCallee() ? 2 : 1; |
| for(final IdentNode parameter: parameters) { |
| currentIncomingSlot += parameter.getType().getSlots(); |
| } |
| // Starting from last parameter going backwards, move the parameter values into their new slots. |
| for(int i = parameters.size(); i-- > 0;) { |
| final IdentNode parameter = parameters.get(i); |
| final Type parameterType = parameter.getType(); |
| final int typeWidth = parameterType.getSlots(); |
| currentIncomingSlot -= typeWidth; |
| final Symbol symbol = parameter.getSymbol(); |
| final int slotCount = symbol.slotCount(); |
| assert slotCount > 0; |
| // Scoped parameters must not hold more than one value |
| assert symbol.isBytecodeLocal() || slotCount == typeWidth; |
| |
| // Mark it as having its value stored into it by the method invocation. |
| method.onLocalStore(parameterType, currentIncomingSlot); |
| if(currentIncomingSlot != symbol.getSlot(parameterType)) { |
| method.load(parameterType, currentIncomingSlot); |
| method.store(symbol, parameterType); |
| } |
| } |
| } |
| |
| private void initArguments(final FunctionNode function) { |
| method.loadCompilerConstant(VARARGS); |
| if (function.needsCallee()) { |
| method.loadCompilerConstant(CALLEE); |
| } else { |
| // If function is strict mode, "arguments.callee" is not populated, so we don't necessarily need the |
| // caller. |
| assert function.isStrict(); |
| method.loadNull(); |
| } |
| method.load(function.getParameters().size()); |
| globalAllocateArguments(); |
| method.storeCompilerConstant(ARGUMENTS); |
| } |
| |
| private boolean skipFunction(final FunctionNode functionNode) { |
| final ScriptEnvironment env = compiler.getScriptEnvironment(); |
| final boolean lazy = env._lazy_compilation; |
| final boolean onDemand = compiler.isOnDemandCompilation(); |
| |
| // If this is on-demand or lazy compilation, don't compile a nested (not topmost) function. |
| if((onDemand || lazy) && lc.getOutermostFunction() != functionNode) { |
| return true; |
| } |
| |
| // If lazy compiling with optimistic types, don't compile the program eagerly either. It will soon be |
| // invalidated anyway. In presence of a class cache, this further means that an obsoleted program version |
| // lingers around. Also, currently loading previously persisted optimistic types information only works if |
| // we're on-demand compiling a function, so with this strategy the :program method can also have the warmup |
| // benefit of using previously persisted types. |
| // |
| // NOTE that this means the first compiled class will effectively just have a :createProgramFunction method, and |
| // the RecompilableScriptFunctionData (RSFD) object in its constants array. It won't even have the :program |
| // method. This is by design. It does mean that we're wasting one compiler execution (and we could minimize this |
| // by just running it up to scope depth calculation, which creates the RSFDs and then this limited codegen). |
| // We could emit an initial separate compile unit with the initial version of :program in it to better utilize |
| // the compilation pipeline, but that would need more invasive changes, as currently the assumption that |
| // :program is emitted into the first compilation unit of the function lives in many places. |
| return !onDemand && lazy && env._optimistic_types && functionNode.isProgram(); |
| } |
| |
| @Override |
| public boolean enterFunctionNode(final FunctionNode functionNode) { |
| if (skipFunction(functionNode)) { |
| // In case we are not generating code for the function, we must create or retrieve the function object and |
| // load it on the stack here. |
| newFunctionObject(functionNode, false); |
| return false; |
| } |
| |
| final String fnName = functionNode.getName(); |
| |
| // NOTE: we only emit the method for a function with the given name once. We can have multiple functions with |
| // the same name as a result of inlining finally blocks. However, in the future -- with type specialization, |
| // notably -- we might need to check for both name *and* signature. Of course, even that might not be |
| // sufficient; the function might have a code dependency on the type of the variables in its enclosing scopes, |
| // and the type of such a variable can be different in catch and finally blocks. So, in the future we will have |
| // to decide to either generate a unique method for each inlined copy of the function, maybe figure out its |
| // exact type closure and deduplicate based on that, or just decide that functions in finally blocks aren't |
| // worth it, and generate one method with most generic type closure. |
| if (!emittedMethods.contains(fnName)) { |
| log.info("=== BEGIN ", fnName); |
| |
| assert functionNode.getCompileUnit() != null : "no compile unit for " + fnName + " " + Debug.id(functionNode); |
| unit = lc.pushCompileUnit(functionNode.getCompileUnit()); |
| assert lc.hasCompileUnits(); |
| |
| final ClassEmitter classEmitter = unit.getClassEmitter(); |
| pushMethodEmitter(isRestOf() ? classEmitter.restOfMethod(functionNode) : classEmitter.method(functionNode)); |
| method.setPreventUndefinedLoad(); |
| if(useOptimisticTypes()) { |
| lc.pushUnwarrantedOptimismHandlers(); |
| } |
| |
| // new method - reset last line number |
| lastLineNumber = -1; |
| |
| method.begin(); |
| |
| if (isRestOf()) { |
| assert continuationInfo == null; |
| continuationInfo = new ContinuationInfo(); |
| method.gotoLoopStart(continuationInfo.getHandlerLabel()); |
| } |
| } |
| |
| return true; |
| } |
| |
| private void pushMethodEmitter(final MethodEmitter newMethod) { |
| method = lc.pushMethodEmitter(newMethod); |
| catchLabels.push(METHOD_BOUNDARY); |
| } |
| |
| private void popMethodEmitter() { |
| method = lc.popMethodEmitter(method); |
| assert catchLabels.peek() == METHOD_BOUNDARY; |
| catchLabels.pop(); |
| } |
| |
| @Override |
| public Node leaveFunctionNode(final FunctionNode functionNode) { |
| try { |
| final boolean markOptimistic; |
| if (emittedMethods.add(functionNode.getName())) { |
| markOptimistic = generateUnwarrantedOptimismExceptionHandlers(functionNode); |
| generateContinuationHandler(); |
| method.end(); // wrap up this method |
| unit = lc.popCompileUnit(functionNode.getCompileUnit()); |
| popMethodEmitter(); |
| log.info("=== END ", functionNode.getName()); |
| } else { |
| markOptimistic = false; |
| } |
| |
| FunctionNode newFunctionNode = functionNode; |
| if (markOptimistic) { |
| newFunctionNode = newFunctionNode.setFlag(lc, FunctionNode.IS_DEOPTIMIZABLE); |
| } |
| |
| newFunctionObject(newFunctionNode, true); |
| return newFunctionNode; |
| } catch (final Throwable t) { |
| Context.printStackTrace(t); |
| final VerifyError e = new VerifyError("Code generation bug in \"" + functionNode.getName() + "\": likely stack misaligned: " + t + " " + functionNode.getSource().getName()); |
| e.initCause(t); |
| throw e; |
| } |
| } |
| |
| @Override |
| public boolean enterIfNode(final IfNode ifNode) { |
| if(!method.isReachable()) { |
| return false; |
| } |
| enterStatement(ifNode); |
| |
| final Expression test = ifNode.getTest(); |
| final Block pass = ifNode.getPass(); |
| final Block fail = ifNode.getFail(); |
| |
| if (Expression.isAlwaysTrue(test)) { |
| loadAndDiscard(test); |
| pass.accept(this); |
| return false; |
| } else if (Expression.isAlwaysFalse(test)) { |
| loadAndDiscard(test); |
| if (fail != null) { |
| fail.accept(this); |
| } |
| return false; |
| } |
| |
| final boolean hasFailConversion = LocalVariableConversion.hasLiveConversion(ifNode); |
| |
| final Label failLabel = new Label("if_fail"); |
| final Label afterLabel = (fail == null && !hasFailConversion) ? null : new Label("if_done"); |
| |
| emitBranch(test, failLabel, false); |
| |
| pass.accept(this); |
| if(method.isReachable() && afterLabel != null) { |
| method._goto(afterLabel); //don't fallthru to fail block |
| } |
| method.label(failLabel); |
| |
| if (fail != null) { |
| fail.accept(this); |
| } else if(hasFailConversion) { |
| method.beforeJoinPoint(ifNode); |
| } |
| |
| if(afterLabel != null && afterLabel.isReachable()) { |
| method.label(afterLabel); |
| } |
| |
| return false; |
| } |
| |
| private void emitBranch(final Expression test, final Label label, final boolean jumpWhenTrue) { |
| new BranchOptimizer(this, method).execute(test, label, jumpWhenTrue); |
| } |
| |
| private void enterStatement(final Statement statement) { |
| lineNumber(statement); |
| } |
| |
| private void lineNumber(final Statement statement) { |
| lineNumber(statement.getLineNumber()); |
| } |
| |
| private void lineNumber(final int lineNumber) { |
| if (lineNumber != lastLineNumber && lineNumber != Node.NO_LINE_NUMBER) { |
| method.lineNumber(lineNumber); |
| lastLineNumber = lineNumber; |
| } |
| } |
| |
| int getLastLineNumber() { |
| return lastLineNumber; |
| } |
| |
| /** |
| * Load a list of nodes as an array of a specific type |
| * The array will contain the visited nodes. |
| * |
| * @param arrayLiteralNode the array of contents |
| * @param arrayType the type of the array, e.g. ARRAY_NUMBER or ARRAY_OBJECT |
| */ |
| private void loadArray(final ArrayLiteralNode arrayLiteralNode, final ArrayType arrayType) { |
| assert arrayType == Type.INT_ARRAY || arrayType == Type.LONG_ARRAY || arrayType == Type.NUMBER_ARRAY || arrayType == Type.OBJECT_ARRAY; |
| |
| final Expression[] nodes = arrayLiteralNode.getValue(); |
| final Object presets = arrayLiteralNode.getPresets(); |
| final int[] postsets = arrayLiteralNode.getPostsets(); |
| final List<Splittable.SplitRange> ranges = arrayLiteralNode.getSplitRanges(); |
| |
| loadConstant(presets); |
| |
| final Type elementType = arrayType.getElementType(); |
| |
| if (ranges != null) { |
| |
| loadSplitLiteral(new SplitLiteralCreator() { |
| @Override |
| public void populateRange(final MethodEmitter method, final Type type, final int slot, final int start, final int end) { |
| for (int i = start; i < end; i++) { |
| method.load(type, slot); |
| storeElement(nodes, elementType, postsets[i]); |
| } |
| method.load(type, slot); |
| } |
| }, ranges, arrayType); |
| |
| return; |
| } |
| |
| if(postsets.length > 0) { |
| final int arraySlot = method.getUsedSlotsWithLiveTemporaries(); |
| method.storeTemp(arrayType, arraySlot); |
| for (final int postset : postsets) { |
| method.load(arrayType, arraySlot); |
| storeElement(nodes, elementType, postset); |
| } |
| method.load(arrayType, arraySlot); |
| } |
| } |
| |
| private void storeElement(final Expression[] nodes, final Type elementType, final int index) { |
| method.load(index); |
| |
| final Expression element = nodes[index]; |
| |
| if (element == null) { |
| method.loadEmpty(elementType); |
| } else { |
| loadExpressionAsType(element, elementType); |
| } |
| |
| method.arraystore(); |
| } |
| |
| private MethodEmitter loadArgsArray(final List<Expression> args) { |
| final Object[] array = new Object[args.size()]; |
| loadConstant(array); |
| |
| for (int i = 0; i < args.size(); i++) { |
| method.dup(); |
| method.load(i); |
| loadExpression(args.get(i), TypeBounds.OBJECT); // variable arity methods always take objects |
| method.arraystore(); |
| } |
| |
| return method; |
| } |
| |
| /** |
| * Load a constant from the constant array. This is only public to be callable from the objects |
| * subpackage. Do not call directly. |
| * |
| * @param string string to load |
| */ |
| void loadConstant(final String string) { |
| final String unitClassName = unit.getUnitClassName(); |
| final ClassEmitter classEmitter = unit.getClassEmitter(); |
| final int index = compiler.getConstantData().add(string); |
| |
| method.load(index); |
| method.invokestatic(unitClassName, GET_STRING.symbolName(), methodDescriptor(String.class, int.class)); |
| classEmitter.needGetConstantMethod(String.class); |
| } |
| |
| /** |
| * Load a constant from the constant array. This is only public to be callable from the objects |
| * subpackage. Do not call directly. |
| * |
| * @param object object to load |
| */ |
| void loadConstant(final Object object) { |
| loadConstant(object, unit, method); |
| } |
| |
| private void loadConstant(final Object object, final CompileUnit compileUnit, final MethodEmitter methodEmitter) { |
| final String unitClassName = compileUnit.getUnitClassName(); |
| final ClassEmitter classEmitter = compileUnit.getClassEmitter(); |
| final int index = compiler.getConstantData().add(object); |
| final Class<?> cls = object.getClass(); |
| |
| if (cls == PropertyMap.class) { |
| methodEmitter.load(index); |
| methodEmitter.invokestatic(unitClassName, GET_MAP.symbolName(), methodDescriptor(PropertyMap.class, int.class)); |
| classEmitter.needGetConstantMethod(PropertyMap.class); |
| } else if (cls.isArray()) { |
| methodEmitter.load(index); |
| final String methodName = ClassEmitter.getArrayMethodName(cls); |
| methodEmitter.invokestatic(unitClassName, methodName, methodDescriptor(cls, int.class)); |
| classEmitter.needGetConstantMethod(cls); |
| } else { |
| methodEmitter.loadConstants().load(index).arrayload(); |
| if (object instanceof ArrayData) { |
| methodEmitter.checkcast(ArrayData.class); |
| methodEmitter.invoke(virtualCallNoLookup(ArrayData.class, "copy", ArrayData.class)); |
| } else if (cls != Object.class) { |
| methodEmitter.checkcast(cls); |
| } |
| } |
| } |
| |
| private void loadConstantsAndIndex(final Object object, final MethodEmitter methodEmitter) { |
| methodEmitter.loadConstants().load(compiler.getConstantData().add(object)); |
| } |
| |
| // literal values |
| private void loadLiteral(final LiteralNode<?> node, final TypeBounds resultBounds) { |
| final Object value = node.getValue(); |
| |
| if (value == null) { |
| method.loadNull(); |
| } else if (value instanceof Undefined) { |
| method.loadUndefined(resultBounds.within(Type.OBJECT)); |
| } else if (value instanceof String) { |
| final String string = (String)value; |
| |
| if (string.length() > MethodEmitter.LARGE_STRING_THRESHOLD / 3) { // 3 == max bytes per encoded char |
| loadConstant(string); |
| } else { |
| method.load(string); |
| } |
| } else if (value instanceof RegexToken) { |
| loadRegex((RegexToken)value); |
| } else if (value instanceof Boolean) { |
| method.load((Boolean)value); |
| } else if (value instanceof Integer) { |
| if(!resultBounds.canBeNarrowerThan(Type.OBJECT)) { |
| method.load((Integer)value); |
| method.convert(Type.OBJECT); |
| } else if(!resultBounds.canBeNarrowerThan(Type.NUMBER)) { |
| method.load(((Integer)value).doubleValue()); |
| } else if(!resultBounds.canBeNarrowerThan(Type.LONG)) { |
| method.load(((Integer)value).longValue()); |
| } else { |
| method.load((Integer)value); |
| } |
| } else if (value instanceof Long) { |
| if(!resultBounds.canBeNarrowerThan(Type.OBJECT)) { |
| method.load((Long)value); |
| method.convert(Type.OBJECT); |
| } else if(!resultBounds.canBeNarrowerThan(Type.NUMBER)) { |
| method.load(((Long)value).doubleValue()); |
| } else { |
| method.load((Long)value); |
| } |
| } else if (value instanceof Double) { |
| if(!resultBounds.canBeNarrowerThan(Type.OBJECT)) { |
| method.load((Double)value); |
| method.convert(Type.OBJECT); |
| } else { |
| method.load((Double)value); |
| } |
| } else if (node instanceof ArrayLiteralNode) { |
| final ArrayLiteralNode arrayLiteral = (ArrayLiteralNode)node; |
| final ArrayType atype = arrayLiteral.getArrayType(); |
| loadArray(arrayLiteral, atype); |
| globalAllocateArray(atype); |
| } else { |
| throw new UnsupportedOperationException("Unknown literal for " + node.getClass() + " " + value.getClass() + " " + value); |
| } |
| } |
| |
| private MethodEmitter loadRegexToken(final RegexToken value) { |
| method.load(value.getExpression()); |
| method.load(value.getOptions()); |
| return globalNewRegExp(); |
| } |
| |
| private MethodEmitter loadRegex(final RegexToken regexToken) { |
| if (regexFieldCount > MAX_REGEX_FIELDS) { |
| return loadRegexToken(regexToken); |
| } |
| // emit field |
| final String regexName = lc.getCurrentFunction().uniqueName(REGEX_PREFIX.symbolName()); |
| final ClassEmitter classEmitter = unit.getClassEmitter(); |
| |
| classEmitter.field(EnumSet.of(PRIVATE, STATIC), regexName, Object.class); |
| regexFieldCount++; |
| |
| // get field, if null create new regex, finally clone regex object |
| method.getStatic(unit.getUnitClassName(), regexName, typeDescriptor(Object.class)); |
| method.dup(); |
| final Label cachedLabel = new Label("cached"); |
| method.ifnonnull(cachedLabel); |
| |
| method.pop(); |
| loadRegexToken(regexToken); |
| method.dup(); |
| method.putStatic(unit.getUnitClassName(), regexName, typeDescriptor(Object.class)); |
| |
| method.label(cachedLabel); |
| globalRegExpCopy(); |
| |
| return method; |
| } |
| |
| /** |
| * Check if a property value contains a particular program point |
| * @param value value |
| * @param pp program point |
| * @return true if it's there. |
| */ |
| private static boolean propertyValueContains(final Expression value, final int pp) { |
| return new Supplier<Boolean>() { |
| boolean contains; |
| |
| @Override |
| public Boolean get() { |
| value.accept(new SimpleNodeVisitor() { |
| @Override |
| public boolean enterFunctionNode(final FunctionNode functionNode) { |
| return false; |
| } |
| |
| @Override |
| public boolean enterObjectNode(final ObjectNode objectNode) { |
| return false; |
| } |
| |
| @Override |
| public boolean enterDefault(final Node node) { |
| if (contains) { |
| return false; |
| } |
| if (node instanceof Optimistic && ((Optimistic)node).getProgramPoint() == pp) { |
| contains = true; |
| return false; |
| } |
| return true; |
| } |
| }); |
| |
| return contains; |
| } |
| }.get(); |
| } |
| |
| private void loadObjectNode(final ObjectNode objectNode) { |
| final List<PropertyNode> elements = objectNode.getElements(); |
| |
| final List<MapTuple<Expression>> tuples = new ArrayList<>(); |
| final List<PropertyNode> gettersSetters = new ArrayList<>(); |
| final int ccp = getCurrentContinuationEntryPoint(); |
| final List<Splittable.SplitRange> ranges = objectNode.getSplitRanges(); |
| |
| Expression protoNode = null; |
| boolean restOfProperty = false; |
| |
| for (final PropertyNode propertyNode : elements) { |
| final Expression value = propertyNode.getValue(); |
| final String key = propertyNode.getKeyName(); |
| // Just use a pseudo-symbol. We just need something non null; use the name and zero flags. |
| final Symbol symbol = value == null ? null : new Symbol(key, 0); |
| |
| if (value == null) { |
| gettersSetters.add(propertyNode); |
| } else if (propertyNode.getKey() instanceof IdentNode && |
| key.equals(ScriptObject.PROTO_PROPERTY_NAME)) { |
| // ES6 draft compliant __proto__ inside object literal |
| // Identifier key and name is __proto__ |
| protoNode = value; |
| continue; |
| } |
| |
| restOfProperty |= |
| value != null && |
| isValid(ccp) && |
| propertyValueContains(value, ccp); |
| |
| //for literals, a value of null means object type, i.e. the value null or getter setter function |
| //(I think) |
| final Class<?> valueType = (!useDualFields() || value == null || value.getType().isBoolean()) ? Object.class : value.getType().getTypeClass(); |
| tuples.add(new MapTuple<Expression>(key, symbol, Type.typeFor(valueType), value) { |
| @Override |
| public Class<?> getValueType() { |
| return type.getTypeClass(); |
| } |
| }); |
| } |
| |
| final ObjectCreator<?> oc; |
| if (elements.size() > OBJECT_SPILL_THRESHOLD) { |
| oc = new SpillObjectCreator(this, tuples); |
| } else { |
| oc = new FieldObjectCreator<Expression>(this, tuples) { |
| @Override |
| protected void loadValue(final Expression node, final Type type) { |
| loadExpressionAsType(node, type); |
| }}; |
| } |
| |
| if (ranges != null) { |
| oc.createObject(method); |
| loadSplitLiteral(oc, ranges, Type.typeFor(oc.getAllocatorClass())); |
| } else { |
| oc.makeObject(method); |
| } |
| |
| //if this is a rest of method and our continuation point was found as one of the values |
| //in the properties above, we need to reset the map to oc.getMap() in the continuation |
| //handler |
| if (restOfProperty) { |
| final ContinuationInfo ci = getContinuationInfo(); |
| // Can be set at most once for a single rest-of method |
| assert ci.getObjectLiteralMap() == null; |
| ci.setObjectLiteralMap(oc.getMap()); |
| ci.setObjectLiteralStackDepth(method.getStackSize()); |
| } |
| |
| method.dup(); |
| if (protoNode != null) { |
| loadExpressionAsObject(protoNode); |
| // take care of { __proto__: 34 } or some such! |
| method.convert(Type.OBJECT); |
| method.invoke(ScriptObject.SET_PROTO_FROM_LITERAL); |
| } else { |
| method.invoke(ScriptObject.SET_GLOBAL_OBJECT_PROTO); |
| } |
| |
| for (final PropertyNode propertyNode : gettersSetters) { |
| final FunctionNode getter = propertyNode.getGetter(); |
| final FunctionNode setter = propertyNode.getSetter(); |
| |
| assert getter != null || setter != null; |
| |
| method.dup().loadKey(propertyNode.getKey()); |
| if (getter == null) { |
| method.loadNull(); |
| } else { |
| getter.accept(this); |
| } |
| |
| if (setter == null) { |
| method.loadNull(); |
| } else { |
| setter.accept(this); |
| } |
| |
| method.invoke(ScriptObject.SET_USER_ACCESSORS); |
| } |
| } |
| |
| @Override |
| public boolean enterReturnNode(final ReturnNode returnNode) { |
| if(!method.isReachable()) { |
| return false; |
| } |
| enterStatement(returnNode); |
| |
| final Type returnType = lc.getCurrentFunction().getReturnType(); |
| |
| final Expression expression = returnNode.getExpression(); |
| if (expression != null) { |
| loadExpressionUnbounded(expression); |
| } else { |
| method.loadUndefined(returnType); |
| } |
| |
| method._return(returnType); |
| |
| return false; |
| } |
| |
| private boolean undefinedCheck(final RuntimeNode runtimeNode, final List<Expression> args) { |
| final Request request = runtimeNode.getRequest(); |
| |
| if (!Request.isUndefinedCheck(request)) { |
| return false; |
| } |
| |
| final Expression lhs = args.get(0); |
| final Expression rhs = args.get(1); |
| |
| final Symbol lhsSymbol = lhs instanceof IdentNode ? ((IdentNode)lhs).getSymbol() : null; |
| final Symbol rhsSymbol = rhs instanceof IdentNode ? ((IdentNode)rhs).getSymbol() : null; |
| // One must be a "undefined" identifier, otherwise we can't get here |
| assert lhsSymbol != null || rhsSymbol != null; |
| |
| final Symbol undefinedSymbol; |
| if (isUndefinedSymbol(lhsSymbol)) { |
| undefinedSymbol = lhsSymbol; |
| } else { |
| assert isUndefinedSymbol(rhsSymbol); |
| undefinedSymbol = rhsSymbol; |
| } |
| |
| assert undefinedSymbol != null; //remove warning |
| if (!undefinedSymbol.isScope()) { |
| return false; //disallow undefined as local var or parameter |
| } |
| |
| if (lhsSymbol == undefinedSymbol && lhs.getType().isPrimitive()) { |
| //we load the undefined first. never mind, because this will deoptimize anyway |
| return false; |
| } |
| |
| if(isDeoptimizedExpression(lhs)) { |
| // This is actually related to "lhs.getType().isPrimitive()" above: any expression being deoptimized in |
| // the current chain of rest-of compilations used to have a type narrower than Object (so it was primitive). |
| // We must not perform undefined check specialization for them, as then we'd violate the basic rule of |
| // "Thou shalt not alter the stack shape between a deoptimized method and any of its (transitive) rest-ofs." |
| return false; |
| } |
| |
| //make sure that undefined has not been overridden or scoped as a local var |
| //between us and global |
| if (!compiler.isGlobalSymbol(lc.getCurrentFunction(), "undefined")) { |
| return false; |
| } |
| |
| final boolean isUndefinedCheck = request == Request.IS_UNDEFINED; |
| final Expression expr = undefinedSymbol == lhsSymbol ? rhs : lhs; |
| if (expr.getType().isPrimitive()) { |
| loadAndDiscard(expr); //throw away lhs, but it still needs to be evaluated for side effects, even if not in scope, as it can be optimistic |
| method.load(!isUndefinedCheck); |
| } else { |
| final Label checkTrue = new Label("ud_check_true"); |
| final Label end = new Label("end"); |
| loadExpressionAsObject(expr); |
| method.loadUndefined(Type.OBJECT); |
| method.if_acmpeq(checkTrue); |
| method.load(!isUndefinedCheck); |
| method._goto(end); |
| method.label(checkTrue); |
| method.load(isUndefinedCheck); |
| method.label(end); |
| } |
| |
| return true; |
| } |
| |
| private static boolean isUndefinedSymbol(final Symbol symbol) { |
| return symbol != null && "undefined".equals(symbol.getName()); |
| } |
| |
| private static boolean isNullLiteral(final Node node) { |
| return node instanceof LiteralNode<?> && ((LiteralNode<?>) node).isNull(); |
| } |
| |
| private boolean nullCheck(final RuntimeNode runtimeNode, final List<Expression> args) { |
| final Request request = runtimeNode.getRequest(); |
| |
| if (!Request.isEQ(request) && !Request.isNE(request)) { |
| return false; |
| } |
| |
| assert args.size() == 2 : "EQ or NE or TYPEOF need two args"; |
| |
| Expression lhs = args.get(0); |
| Expression rhs = args.get(1); |
| |
| if (isNullLiteral(lhs)) { |
| final Expression tmp = lhs; |
| lhs = rhs; |
| rhs = tmp; |
| } |
| |
| if (!isNullLiteral(rhs)) { |
| return false; |
| } |
| |
| if (!lhs.getType().isObject()) { |
| return false; |
| } |
| |
| if(isDeoptimizedExpression(lhs)) { |
| // This is actually related to "!lhs.getType().isObject()" above: any expression being deoptimized in |
| // the current chain of rest-of compilations used to have a type narrower than Object. We must not |
| // perform null check specialization for them, as then we'd no longer be loading aconst_null on stack |
| // and thus violate the basic rule of "Thou shalt not alter the stack shape between a deoptimized |
| // method and any of its (transitive) rest-ofs." |
| // NOTE also that if we had a representation for well-known constants (e.g. null, 0, 1, -1, etc.) in |
| // Label$Stack.localLoads then this wouldn't be an issue, as we would never (somewhat ridiculously) |
| // allocate a temporary local to hold the result of aconst_null before attempting an optimistic |
| // operation. |
| return false; |
| } |
| |
| // this is a null literal check, so if there is implicit coercion |
| // involved like {D}x=null, we will fail - this is very rare |
| final Label trueLabel = new Label("trueLabel"); |
| final Label falseLabel = new Label("falseLabel"); |
| final Label endLabel = new Label("end"); |
| |
| loadExpressionUnbounded(lhs); //lhs |
| final Label popLabel; |
| if (!Request.isStrict(request)) { |
| method.dup(); //lhs lhs |
| popLabel = new Label("pop"); |
| } else { |
| popLabel = null; |
| } |
| |
| if (Request.isEQ(request)) { |
| method.ifnull(!Request.isStrict(request) ? popLabel : trueLabel); |
| if (!Request.isStrict(request)) { |
| method.loadUndefined(Type.OBJECT); |
| method.if_acmpeq(trueLabel); |
| } |
| method.label(falseLabel); |
| method.load(false); |
| method._goto(endLabel); |
| if (!Request.isStrict(request)) { |
| method.label(popLabel); |
| method.pop(); |
| } |
| method.label(trueLabel); |
| method.load(true); |
| method.label(endLabel); |
| } else if (Request.isNE(request)) { |
| method.ifnull(!Request.isStrict(request) ? popLabel : falseLabel); |
| if (!Request.isStrict(request)) { |
| method.loadUndefined(Type.OBJECT); |
| method.if_acmpeq(falseLabel); |
| } |
| method.label(trueLabel); |
| method.load(true); |
| method._goto(endLabel); |
| if (!Request.isStrict(request)) { |
| method.label(popLabel); |
| method.pop(); |
| } |
| method.label(falseLabel); |
| method.load(false); |
| method.label(endLabel); |
| } |
| |
| assert runtimeNode.getType().isBoolean(); |
| method.convert(runtimeNode.getType()); |
| |
| return true; |
| } |
| |
| /** |
| * Was this expression or any of its subexpressions deoptimized in the current recompilation chain of rest-of methods? |
| * @param rootExpr the expression being tested |
| * @return true if the expression or any of its subexpressions was deoptimized in the current recompilation chain. |
| */ |
| private boolean isDeoptimizedExpression(final Expression rootExpr) { |
| if(!isRestOf()) { |
| return false; |
| } |
| return new Supplier<Boolean>() { |
| boolean contains; |
| @Override |
| public Boolean get() { |
| rootExpr.accept(new SimpleNodeVisitor() { |
| @Override |
| public boolean enterFunctionNode(final FunctionNode functionNode) { |
| return false; |
| } |
| @Override |
| public boolean enterDefault(final Node node) { |
| if(!contains && node instanceof Optimistic) { |
| final int pp = ((Optimistic)node).getProgramPoint(); |
| contains = isValid(pp) && isContinuationEntryPoint(pp); |
| } |
| return !contains; |
| } |
| }); |
| return contains; |
| } |
| }.get(); |
| } |
| |
| private void loadRuntimeNode(final RuntimeNode runtimeNode) { |
| final List<Expression> args = new ArrayList<>(runtimeNode.getArgs()); |
| if (nullCheck(runtimeNode, args)) { |
| return; |
| } else if(undefinedCheck(runtimeNode, args)) { |
| return; |
| } |
| // Revert a false undefined check to a strict equality check |
| final RuntimeNode newRuntimeNode; |
| final Request request = runtimeNode.getRequest(); |
| if (Request.isUndefinedCheck(request)) { |
| newRuntimeNode = runtimeNode.setRequest(request == Request.IS_UNDEFINED ? Request.EQ_STRICT : Request.NE_STRICT); |
| } else { |
| newRuntimeNode = runtimeNode; |
| } |
| |
| for (final Expression arg : args) { |
| loadExpression(arg, TypeBounds.OBJECT); |
| } |
| |
| method.invokestatic( |
| CompilerConstants.className(ScriptRuntime.class), |
| newRuntimeNode.getRequest().toString(), |
| new FunctionSignature( |
| false, |
| false, |
| newRuntimeNode.getType(), |
| args.size()).toString()); |
| |
| method.convert(newRuntimeNode.getType()); |
| } |
| |
| private void defineCommonSplitMethodParameters() { |
| defineSplitMethodParameter(0, CALLEE); |
| defineSplitMethodParameter(1, THIS); |
| defineSplitMethodParameter(2, SCOPE); |
| } |
| |
| private void defineSplitMethodParameter(final int slot, final CompilerConstants cc) { |
| defineSplitMethodParameter(slot, Type.typeFor(cc.type())); |
| } |
| |
| private void defineSplitMethodParameter(final int slot, final Type type) { |
| method.defineBlockLocalVariable(slot, slot + type.getSlots()); |
| method.onLocalStore(type, slot); |
| } |
| |
| private void loadSplitLiteral(final SplitLiteralCreator creator, final List<Splittable.SplitRange> ranges, final Type literalType) { |
| assert ranges != null; |
| |
| // final Type literalType = Type.typeFor(literalClass); |
| final MethodEmitter savedMethod = method; |
| final FunctionNode currentFunction = lc.getCurrentFunction(); |
| |
| for (final Splittable.SplitRange splitRange : ranges) { |
| unit = lc.pushCompileUnit(splitRange.getCompileUnit()); |
| |
| assert unit != null; |
| final String className = unit.getUnitClassName(); |
| final String name = currentFunction.uniqueName(SPLIT_PREFIX.symbolName()); |
| final Class<?> clazz = literalType.getTypeClass(); |
| final String signature = methodDescriptor(clazz, ScriptFunction.class, Object.class, ScriptObject.class, clazz); |
| |
| pushMethodEmitter(unit.getClassEmitter().method(EnumSet.of(Flag.PUBLIC, Flag.STATIC), name, signature)); |
| |
| method.setFunctionNode(currentFunction); |
| method.begin(); |
| |
| defineCommonSplitMethodParameters(); |
| defineSplitMethodParameter(CompilerConstants.SPLIT_ARRAY_ARG.slot(), literalType); |
| |
| // NOTE: when this is no longer needed, SplitIntoFunctions will no longer have to add IS_SPLIT |
| // to synthetic functions, and FunctionNode.needsCallee() will no longer need to test for isSplit(). |
| final int literalSlot = fixScopeSlot(currentFunction, 3); |
| |
| lc.enterSplitNode(); |
| |
| creator.populateRange(method, literalType, literalSlot, splitRange.getLow(), splitRange.getHigh()); |
| |
| method._return(); |
| lc.exitSplitNode(); |
| method.end(); |
| lc.releaseSlots(); |
| popMethodEmitter(); |
| |
| assert method == savedMethod; |
| method.loadCompilerConstant(CALLEE).swap(); |
| method.loadCompilerConstant(THIS).swap(); |
| method.loadCompilerConstant(SCOPE).swap(); |
| method.invokestatic(className, name, signature); |
| |
| unit = lc.popCompileUnit(unit); |
| } |
| } |
| |
| private int fixScopeSlot(final FunctionNode functionNode, final int extraSlot) { |
| // TODO hack to move the scope to the expected slot (needed because split methods reuse the same slots as the root method) |
| final int actualScopeSlot = functionNode.compilerConstant(SCOPE).getSlot(SCOPE_TYPE); |
| final int defaultScopeSlot = SCOPE.slot(); |
| int newExtraSlot = extraSlot; |
| if (actualScopeSlot != defaultScopeSlot) { |
| if (actualScopeSlot == extraSlot) { |
| newExtraSlot = extraSlot + 1; |
| method.defineBlockLocalVariable(newExtraSlot, newExtraSlot + 1); |
| method.load(Type.OBJECT, extraSlot); |
| method.storeHidden(Type.OBJECT, newExtraSlot); |
| } else { |
| method.defineBlockLocalVariable(actualScopeSlot, actualScopeSlot + 1); |
| } |
| method.load(SCOPE_TYPE, defaultScopeSlot); |
| method.storeCompilerConstant(SCOPE); |
| } |
| return newExtraSlot; |
| } |
| |
| @Override |
| public boolean enterSplitReturn(final SplitReturn splitReturn) { |
| if (method.isReachable()) { |
| method.loadUndefined(lc.getCurrentFunction().getReturnType())._return(); |
| } |
| return false; |
| } |
| |
| @Override |
| public boolean enterSetSplitState(final SetSplitState setSplitState) { |
| if (method.isReachable()) { |
| method.setSplitState(setSplitState.getState()); |
| } |
| return false; |
| } |
| |
| @Override |
| public boolean enterSwitchNode(final SwitchNode switchNode) { |
| if(!method.isReachable()) { |
| return false; |
| } |
| enterStatement(switchNode); |
| |
| final Expression expression = switchNode.getExpression(); |
| final List<CaseNode> cases = switchNode.getCases(); |
| |
| if (cases.isEmpty()) { |
| // still evaluate expression for side-effects. |
| loadAndDiscard(expression); |
| return false; |
| } |
| |
| final CaseNode defaultCase = switchNode.getDefaultCase(); |
| final Label breakLabel = switchNode.getBreakLabel(); |
| final int liveLocalsOnBreak = method.getUsedSlotsWithLiveTemporaries(); |
| |
| if (defaultCase != null && cases.size() == 1) { |
| // default case only |
| assert cases.get(0) == defaultCase; |
| loadAndDiscard(expression); |
| defaultCase.getBody().accept(this); |
| method.breakLabel(breakLabel, liveLocalsOnBreak); |
| return false; |
| } |
| |
| // NOTE: it can still change in the tableswitch/lookupswitch case if there's no default case |
| // but we need to add a synthetic default case for local variable conversions |
| Label defaultLabel = defaultCase != null ? defaultCase.getEntry() : breakLabel; |
| final boolean hasSkipConversion = LocalVariableConversion.hasLiveConversion(switchNode); |
| |
| if (switchNode.isUniqueInteger()) { |
| // Tree for sorting values. |
| final TreeMap<Integer, Label> tree = new TreeMap<>(); |
| |
| // Build up sorted tree. |
| for (final CaseNode caseNode : cases) { |
| final Node test = caseNode.getTest(); |
| |
| if (test != null) { |
| final Integer value = (Integer)((LiteralNode<?>)test).getValue(); |
| final Label entry = caseNode.getEntry(); |
| |
| // Take first duplicate. |
| if (!tree.containsKey(value)) { |
| tree.put(value, entry); |
| } |
| } |
| } |
| |
| // Copy values and labels to arrays. |
| final int size = tree.size(); |
| final Integer[] values = tree.keySet().toArray(new Integer[size]); |
| final Label[] labels = tree.values().toArray(new Label[size]); |
| |
| // Discern low, high and range. |
| final int lo = values[0]; |
| final int hi = values[size - 1]; |
| final long range = (long)hi - (long)lo + 1; |
| |
| // Find an unused value for default. |
| int deflt = Integer.MIN_VALUE; |
| for (final int value : values) { |
| if (deflt == value) { |
| deflt++; |
| } else if (deflt < value) { |
| break; |
| } |
| } |
| |
| // Load switch expression. |
| loadExpressionUnbounded(expression); |
| final Type type = expression.getType(); |
| |
| // If expression not int see if we can convert, if not use deflt to trigger default. |
| if (!type.isInteger()) { |
| method.load(deflt); |
| final Class<?> exprClass = type.getTypeClass(); |
| method.invoke(staticCallNoLookup(ScriptRuntime.class, "switchTagAsInt", int.class, exprClass.isPrimitive()? exprClass : Object.class, int.class)); |
| } |
| |
| if(hasSkipConversion) { |
| assert defaultLabel == breakLabel; |
| defaultLabel = new Label("switch_skip"); |
| } |
| // TABLESWITCH needs (range + 3) 32-bit values; LOOKUPSWITCH needs ((size * 2) + 2). Choose the one with |
| // smaller representation, favor TABLESWITCH when they're equal size. |
| if (range + 1 <= (size * 2) && range <= Integer.MAX_VALUE) { |
| final Label[] table = new Label[(int)range]; |
| Arrays.fill(table, defaultLabel); |
| for (int i = 0; i < size; i++) { |
| final int value = values[i]; |
| table[value - lo] = labels[i]; |
| } |
| |
| method.tableswitch(lo, hi, defaultLabel, table); |
| } else { |
| final int[] ints = new int[size]; |
| for (int i = 0; i < size; i++) { |
| ints[i] = values[i]; |
| } |
| |
| method.lookupswitch(defaultLabel, ints, labels); |
| } |
| // This is a synthetic "default case" used in absence of actual default case, created if we need to apply |
| // local variable conversions if neither case is taken. |
| if(hasSkipConversion) { |
| method.label(defaultLabel); |
| method.beforeJoinPoint(switchNode); |
| method._goto(breakLabel); |
| } |
| } else { |
| final Symbol tagSymbol = switchNode.getTag(); |
| // TODO: we could have non-object tag |
| final int tagSlot = tagSymbol.getSlot(Type.OBJECT); |
| loadExpressionAsObject(expression); |
| method.store(tagSymbol, Type.OBJECT); |
| |
| for (final CaseNode caseNode : cases) { |
| final Expression test = caseNode.getTest(); |
| |
| if (test != null) { |
| method.load(Type.OBJECT, tagSlot); |
| loadExpressionAsObject(test); |
| method.invoke(ScriptRuntime.EQ_STRICT); |
| method.ifne(caseNode.getEntry()); |
| } |
| } |
| |
| if (defaultCase != null) { |
| method._goto(defaultLabel); |
| } else { |
| method.beforeJoinPoint(switchNode); |
| method._goto(breakLabel); |
| } |
| } |
| |
| // First case is only reachable through jump |
| assert !method.isReachable(); |
| |
| for (final CaseNode caseNode : cases) { |
| final Label fallThroughLabel; |
| if(caseNode.getLocalVariableConversion() != null && method.isReachable()) { |
| fallThroughLabel = new Label("fallthrough"); |
| method._goto(fallThroughLabel); |
| } else { |
| fallThroughLabel = null; |
| } |
| method.label(caseNode.getEntry()); |
| method.beforeJoinPoint(caseNode); |
| if(fallThroughLabel != null) { |
| method.label(fallThroughLabel); |
| } |
| caseNode.getBody().accept(this); |
| } |
| |
| method.breakLabel(breakLabel, liveLocalsOnBreak); |
| |
| return false; |
| } |
| |
| @Override |
| public boolean enterThrowNode(final ThrowNode throwNode) { |
| if(!method.isReachable()) { |
| return false; |
| } |
| enterStatement(throwNode); |
| |
| if (throwNode.isSyntheticRethrow()) { |
| method.beforeJoinPoint(throwNode); |
| |
| //do not wrap whatever this is in an ecma exception, just rethrow it |
| final IdentNode exceptionExpr = (IdentNode)throwNode.getExpression(); |
| final Symbol exceptionSymbol = exceptionExpr.getSymbol(); |
| method.load(exceptionSymbol, EXCEPTION_TYPE); |
| method.checkcast(EXCEPTION_TYPE.getTypeClass()); |
| method.athrow(); |
| return false; |
| } |
| |
| final Source source = getCurrentSource(); |
| final Expression expression = throwNode.getExpression(); |
| final int position = throwNode.position(); |
| final int line = throwNode.getLineNumber(); |
| final int column = source.getColumn(position); |
| |
| // NOTE: we first evaluate the expression, and only after it was evaluated do we create the new ECMAException |
| // object and then somewhat cumbersomely move it beneath the evaluated expression on the stack. The reason for |
| // this is that if expression is optimistic (or contains an optimistic subexpression), we'd potentially access |
| // the not-yet-<init>ialized object on the stack from the UnwarrantedOptimismException handler, and bytecode |
| // verifier forbids that. |
| loadExpressionAsObject(expression); |
| |
| method.load(source.getName()); |
| method.load(line); |
| method.load(column); |
| method.invoke(ECMAException.CREATE); |
| |
| method.beforeJoinPoint(throwNode); |
| method.athrow(); |
| |
| return false; |
| } |
| |
| private Source getCurrentSource() { |
| return lc.getCurrentFunction().getSource(); |
| } |
| |
| @Override |
| public boolean enterTryNode(final TryNode tryNode) { |
| if(!method.isReachable()) { |
| return false; |
| } |
| enterStatement(tryNode); |
| |
| final Block body = tryNode.getBody(); |
| final List<Block> catchBlocks = tryNode.getCatchBlocks(); |
| final Symbol vmException = tryNode.getException(); |
| final Label entry = new Label("try"); |
| final Label recovery = new Label("catch"); |
| final Label exit = new Label("end_try"); |
| final Label skip = new Label("skip"); |
| |
| method.canThrow(recovery); |
| // Effect any conversions that might be observed at the entry of the catch node before entering the try node. |
| // This is because even the first instruction in the try block must be presumed to be able to transfer control |
| // to the catch block. Note that this doesn't kill the original values; in this regard it works a lot like |
| // conversions of assignments within the try block. |
| method.beforeTry(tryNode, recovery); |
| method.label(entry); |
| catchLabels.push(recovery); |
| try { |
| body.accept(this); |
| } finally { |
| assert catchLabels.peek() == recovery; |
| catchLabels.pop(); |
| } |
| |
| method.label(exit); |
| final boolean bodyCanThrow = exit.isAfter(entry); |
| if(!bodyCanThrow) { |
| // The body can't throw an exception; don't even bother emitting the catch handlers, they're all dead code. |
| return false; |
| } |
| |
| method._try(entry, exit, recovery, Throwable.class); |
| |
| if (method.isReachable()) { |
| method._goto(skip); |
| } |
| |
| for (final Block inlinedFinally : tryNode.getInlinedFinallies()) { |
| TryNode.getLabelledInlinedFinallyBlock(inlinedFinally).accept(this); |
| // All inlined finallies end with a jump or a return |
| assert !method.isReachable(); |
| } |
| |
| |
| method._catch(recovery); |
| method.store(vmException, EXCEPTION_TYPE); |
| |
| final int catchBlockCount = catchBlocks.size(); |
| final Label afterCatch = new Label("after_catch"); |
| for (int i = 0; i < catchBlockCount; i++) { |
| assert method.isReachable(); |
| final Block catchBlock = catchBlocks.get(i); |
| |
| // Because of the peculiarities of the flow control, we need to use an explicit push/enterBlock/leaveBlock |
| // here. |
| lc.push(catchBlock); |
| enterBlock(catchBlock); |
| |
| final CatchNode catchNode = (CatchNode)catchBlocks.get(i).getStatements().get(0); |
| final IdentNode exception = catchNode.getException(); |
| final Expression exceptionCondition = catchNode.getExceptionCondition(); |
| final Block catchBody = catchNode.getBody(); |
| |
| new Store<IdentNode>(exception) { |
| @Override |
| protected void storeNonDiscard() { |
| // This expression is neither part of a discard, nor needs to be left on the stack after it was |
| // stored, so we override storeNonDiscard to be a no-op. |
| } |
| |
| @Override |
| protected void evaluate() { |
| if (catchNode.isSyntheticRethrow()) { |
| method.load(vmException, EXCEPTION_TYPE); |
| return; |
| } |
| /* |
| * If caught object is an instance of ECMAException, then |
| * bind obj.thrown to the script catch var. Or else bind the |
| * caught object itself to the script catch var. |
| */ |
| final Label notEcmaException = new Label("no_ecma_exception"); |
| method.load(vmException, EXCEPTION_TYPE).dup()._instanceof(ECMAException.class).ifeq(notEcmaException); |
| method.checkcast(ECMAException.class); //TODO is this necessary? |
| method.getField(ECMAException.THROWN); |
| method.label(notEcmaException); |
| } |
| }.store(); |
| |
| final boolean isConditionalCatch = exceptionCondition != null; |
| final Label nextCatch; |
| if (isConditionalCatch) { |
| loadExpressionAsBoolean(exceptionCondition); |
| nextCatch = new Label("next_catch"); |
| nextCatch.markAsBreakTarget(); |
| method.ifeq(nextCatch); |
| } else { |
| nextCatch = null; |
| } |
| |
| catchBody.accept(this); |
| leaveBlock(catchBlock); |
| lc.pop(catchBlock); |
| if(nextCatch != null) { |
| if(method.isReachable()) { |
| method._goto(afterCatch); |
| } |
| method.breakLabel(nextCatch, lc.getUsedSlotCount()); |
| } |
| } |
| |
| // afterCatch could be the same as skip, except that we need to establish that the vmException is dead. |
| method.label(afterCatch); |
| if(method.isReachable()) { |
| method.markDeadLocalVariable(vmException); |
| } |
| method.label(skip); |
| |
| // Finally body is always inlined elsewhere so it doesn't need to be emitted |
| assert tryNode.getFinallyBody() == null; |
| |
| return false; |
| } |
| |
| @Override |
| public boolean enterVarNode(final VarNode varNode) { |
| if(!method.isReachable()) { |
| return false; |
| } |
| final Expression init = varNode.getInit(); |
| final IdentNode identNode = varNode.getName(); |
| final Symbol identSymbol = identNode.getSymbol(); |
| assert identSymbol != null : "variable node " + varNode + " requires a name with a symbol"; |
| final boolean needsScope = identSymbol.isScope(); |
| |
| if (init == null) { |
| if (needsScope && varNode.isBlockScoped()) { |
| // block scoped variables need a DECLARE flag to signal end of temporal dead zone (TDZ) |
| method.loadCompilerConstant(SCOPE); |
| method.loadUndefined(Type.OBJECT); |
| final int flags = getScopeCallSiteFlags(identSymbol) | (varNode.isBlockScoped() ? CALLSITE_DECLARE : 0); |
| assert isFastScope(identSymbol); |
| storeFastScopeVar(identSymbol, flags); |
| } |
| return false; |
| } |
| |
| enterStatement(varNode); |
| assert method != null; |
| |
| if (needsScope) { |
| method.loadCompilerConstant(SCOPE); |
| } |
| |
| if (needsScope) { |
| loadExpressionUnbounded(init); |
| // block scoped variables need a DECLARE flag to signal end of temporal dead zone (TDZ) |
| final int flags = getScopeCallSiteFlags(identSymbol) | (varNode.isBlockScoped() ? CALLSITE_DECLARE : 0); |
| if (isFastScope(identSymbol)) { |
| storeFastScopeVar(identSymbol, flags); |
| } else { |
| method.dynamicSet(identNode.getName(), flags, false); |
| } |
| } else { |
| final Type identType = identNode.getType(); |
| if(identType == Type.UNDEFINED) { |
| // The initializer is either itself undefined (explicit assignment of undefined to undefined), |
| // or the left hand side is a dead variable. |
| assert init.getType() == Type.UNDEFINED || identNode.getSymbol().slotCount() == 0; |
| loadAndDiscard(init); |
| return false; |
| } |
| loadExpressionAsType(init, identType); |
| storeIdentWithCatchConversion(identNode, identType); |
| } |
| |
| return false; |
| } |
| |
| private void storeIdentWithCatchConversion(final IdentNode identNode, final Type type) { |
| // Assignments happening in try/catch blocks need to ensure that they also store a possibly wider typed value |
| // that will be live at the exit from the try block |
| final LocalVariableConversion conversion = identNode.getLocalVariableConversion(); |
| final Symbol symbol = identNode.getSymbol(); |
| if(conversion != null && conversion.isLive()) { |
| assert symbol == conversion.getSymbol(); |
| assert symbol.isBytecodeLocal(); |
| // Only a single conversion from the target type to the join type is expected. |
| assert conversion.getNext() == null; |
| assert conversion.getFrom() == type; |
| // We must propagate potential type change to the catch block |
| final Label catchLabel = catchLabels.peek(); |
| assert catchLabel != METHOD_BOUNDARY; // ident conversion only exists in try blocks |
| assert catchLabel.isReachable(); |
| final Type joinType = conversion.getTo(); |
| final Label.Stack catchStack = catchLabel.getStack(); |
| final int joinSlot = symbol.getSlot(joinType); |
| // With nested try/catch blocks (incl. synthetic ones for finally), we can have a supposed conversion for |
| // the exception symbol in the nested catch, but it isn't live in the outer catch block, so prevent doing |
| // conversions for it. E.g. in "try { try { ... } catch(e) { e = 1; } } catch(e2) { ... }", we must not |
| // introduce an I->O conversion on "e = 1" assignment as "e" is not live in "catch(e2)". |
| if(catchStack.getUsedSlotsWithLiveTemporaries() > joinSlot) { |
| method.dup(); |
| method.convert(joinType); |
| method.store(symbol, joinType); |
| catchLabel.getStack().onLocalStore(joinType, joinSlot, true); |
| method.canThrow(catchLabel); |
| // Store but keep the previous store live too. |
| method.store(symbol, type, false); |
| return; |
| } |
| } |
| |
| method.store(symbol, type, true); |
| } |
| |
| @Override |
| public boolean enterWhileNode(final WhileNode whileNode) { |
| if(!method.isReachable()) { |
| return false; |
| } |
| if(whileNode.isDoWhile()) { |
| enterDoWhile(whileNode); |
| } else { |
| enterStatement(whileNode); |
| enterForOrWhile(whileNode, null); |
| } |
| return false; |
| } |
| |
| private void enterForOrWhile(final LoopNode loopNode, final JoinPredecessorExpression modify) { |
| // NOTE: the usual pattern for compiling test-first loops is "GOTO test; body; test; IFNE body". We use the less |
| // conventional "test; IFEQ break; body; GOTO test; break;". It has one extra unconditional GOTO in each repeat |
| // of the loop, but it's not a problem for modern JIT compilers. We do this because our local variable type |
| // tracking is unfortunately not really prepared for out-of-order execution, e.g. compiling the following |
| // contrived but legal JavaScript code snippet would fail because the test changes the type of "i" from object |
| // to double: var i = {valueOf: function() { return 1} }; while(--i >= 0) { ... } |
| // Instead of adding more complexity to the local variable type tracking, we instead choose to emit this |
| // different code shape. |
| final int liveLocalsOnBreak = method.getUsedSlotsWithLiveTemporaries(); |
| final JoinPredecessorExpression test = loopNode.getTest(); |
| if(Expression.isAlwaysFalse(test)) { |
| loadAndDiscard(test); |
| return; |
| } |
| |
| method.beforeJoinPoint(loopNode); |
| |
| final Label continueLabel = loopNode.getContinueLabel(); |
| final Label repeatLabel = modify != null ? new Label("for_repeat") : continueLabel; |
| method.label(repeatLabel); |
| final int liveLocalsOnContinue = method.getUsedSlotsWithLiveTemporaries(); |
| |
| final Block body = loopNode.getBody(); |
| final Label breakLabel = loopNode.getBreakLabel(); |
| final boolean testHasLiveConversion = test != null && LocalVariableConversion.hasLiveConversion(test); |
| |
| if(Expression.isAlwaysTrue(test)) { |
| if(test != null) { |
| loadAndDiscard(test); |
| if(testHasLiveConversion) { |
| method.beforeJoinPoint(test); |
| } |
| } |
| } else if (test != null) { |
| if (testHasLiveConversion) { |
| emitBranch(test.getExpression(), body.getEntryLabel(), true); |
| method.beforeJoinPoint(test); |
| method._goto(breakLabel); |
| } else { |
| emitBranch(test.getExpression(), breakLabel, false); |
| } |
| } |
| |
| body.accept(this); |
| if(repeatLabel != continueLabel) { |
| emitContinueLabel(continueLabel, liveLocalsOnContinue); |
| } |
| |
| if (loopNode.hasPerIterationScope() && lc.getCurrentBlock().needsScope()) { |
| // ES6 for loops with LET init need a new scope for each iteration. We just create a shallow copy here. |
| method.loadCompilerConstant(SCOPE); |
| method.invoke(virtualCallNoLookup(ScriptObject.class, "copy", ScriptObject.class)); |
| method.storeCompilerConstant(SCOPE); |
| } |
| |
| if(method.isReachable()) { |
| if(modify != null) { |
| lineNumber(loopNode); |
| loadAndDiscard(modify); |
| method.beforeJoinPoint(modify); |
| } |
| method._goto(repeatLabel); |
| } |
| |
| method.breakLabel(breakLabel, liveLocalsOnBreak); |
| } |
| |
| private void emitContinueLabel(final Label continueLabel, final int liveLocals) { |
| final boolean reachable = method.isReachable(); |
| method.breakLabel(continueLabel, liveLocals); |
| // If we reach here only through a continue statement (e.g. body does not exit normally) then the |
| // continueLabel can have extra non-temp symbols (e.g. exception from a try/catch contained in the body). We |
| // must make sure those are thrown away. |
| if(!reachable) { |
| method.undefineLocalVariables(lc.getUsedSlotCount(), false); |
| } |
| } |
| |
| private void enterDoWhile(final WhileNode whileNode) { |
| final int liveLocalsOnContinueOrBreak = method.getUsedSlotsWithLiveTemporaries(); |
| method.beforeJoinPoint(whileNode); |
| |
| final Block body = whileNode.getBody(); |
| body.accept(this); |
| |
| emitContinueLabel(whileNode.getContinueLabel(), liveLocalsOnContinueOrBreak); |
| if(method.isReachable()) { |
| lineNumber(whileNode); |
| final JoinPredecessorExpression test = whileNode.getTest(); |
| final Label bodyEntryLabel = body.getEntryLabel(); |
| final boolean testHasLiveConversion = LocalVariableConversion.hasLiveConversion(test); |
| if(Expression.isAlwaysFalse(test)) { |
| loadAndDiscard(test); |
| if(testHasLiveConversion) { |
| method.beforeJoinPoint(test); |
| } |
| } else if(testHasLiveConversion) { |
| // If we have conversions after the test in do-while, they need to be effected on both branches. |
| final Label beforeExit = new Label("do_while_preexit"); |
| emitBranch(test.getExpression(), beforeExit, false); |
| method.beforeJoinPoint(test); |
| method._goto(bodyEntryLabel); |
| method.label(beforeExit); |
| method.beforeJoinPoint(test); |
| } else { |
| emitBranch(test.getExpression(), bodyEntryLabel, true); |
| } |
| } |
| method.breakLabel(whileNode.getBreakLabel(), liveLocalsOnContinueOrBreak); |
| } |
| |
| |
| @Override |
| public boolean enterWithNode(final WithNode withNode) { |
| if(!method.isReachable()) { |
| return false; |
| } |
| enterStatement(withNode); |
| final Expression expression = withNode.getExpression(); |
| final Block body = withNode.getBody(); |
| |
| // It is possible to have a "pathological" case where the with block does not reference *any* identifiers. It's |
| // pointless, but legal. In that case, if nothing else in the method forced the assignment of a slot to the |
| // scope object, its' possible that it won't have a slot assigned. In this case we'll only evaluate expression |
| // for its side effect and visit the body, and not bother opening and closing a WithObject. |
| final boolean hasScope = method.hasScope(); |
| |
| if (hasScope) { |
| method.loadCompilerConstant(SCOPE); |
| } |
| |
| loadExpressionAsObject(expression); |
| |
| final Label tryLabel; |
| if (hasScope) { |
| // Construct a WithObject if we have a scope |
| method.invoke(ScriptRuntime.OPEN_WITH); |
| method.storeCompilerConstant(SCOPE); |
| tryLabel = new Label("with_try"); |
| method.label(tryLabel); |
| } else { |
| // We just loaded the expression for its side effect and to check |
| // for null or undefined value. |
| globalCheckObjectCoercible(); |
| tryLabel = null; |
| } |
| |
| // Always process body |
| body.accept(this); |
| |
| if (hasScope) { |
| // Ensure we always close the WithObject |
| final Label endLabel = new Label("with_end"); |
| final Label catchLabel = new Label("with_catch"); |
| final Label exitLabel = new Label("with_exit"); |
| |
| method.label(endLabel); |
| // Somewhat conservatively presume that if the body is not empty, it can throw an exception. In any case, |
| // we must prevent trying to emit a try-catch for empty range, as it causes a verification error. |
| final boolean bodyCanThrow = endLabel.isAfter(tryLabel); |
| if(bodyCanThrow) { |
| method._try(tryLabel, endLabel, catchLabel); |
| } |
| |
| final boolean reachable = method.isReachable(); |
| if(reachable) { |
| popScope(); |
| if(bodyCanThrow) { |
| method._goto(exitLabel); |
| } |
| } |
| |
| if(bodyCanThrow) { |
| method._catch(catchLabel); |
| popScopeException(); |
| method.athrow(); |
| if(reachable) { |
| method.label(exitLabel); |
| } |
| } |
| } |
| return false; |
| } |
| |
| private void loadADD(final UnaryNode unaryNode, final TypeBounds resultBounds) { |
| loadExpression(unaryNode.getExpression(), resultBounds.booleanToInt().notWiderThan(Type.NUMBER)); |
| if(method.peekType() == Type.BOOLEAN) { |
| // It's a no-op in bytecode, but we must make sure it is treated as an int for purposes of type signatures |
| method.convert(Type.INT); |
| } |
| } |
| |
| private void loadBIT_NOT(final UnaryNode unaryNode) { |
| loadExpression(unaryNode.getExpression(), TypeBounds.INT).load(-1).xor(); |
| } |
| |
| private void loadDECINC(final UnaryNode unaryNode) { |
| final Expression operand = unaryNode.getExpression(); |
| final Type type = unaryNode.getType(); |
| final TypeBounds typeBounds = new TypeBounds(type, Type.NUMBER); |
| final TokenType tokenType = unaryNode.tokenType(); |
| final boolean isPostfix = tokenType == TokenType.DECPOSTFIX || tokenType == TokenType.INCPOSTFIX; |
| final boolean isIncrement = tokenType == TokenType.INCPREFIX || tokenType == TokenType.INCPOSTFIX; |
| |
| assert !type.isObject(); |
| |
| new SelfModifyingStore<UnaryNode>(unaryNode, operand) { |
| |
| private void loadRhs() { |
| loadExpression(operand, typeBounds, true); |
| } |
| |
| @Override |
| protected void evaluate() { |
| if(isPostfix) { |
| loadRhs(); |
| } else { |
| new OptimisticOperation(unaryNode, typeBounds) { |
| @Override |
| void loadStack() { |
| loadRhs(); |
| loadMinusOne(); |
| } |
| @Override |
| void consumeStack() { |
| doDecInc(getProgramPoint()); |
| } |
| }.emit(getOptimisticIgnoreCountForSelfModifyingExpression(operand)); |
| } |
| } |
| |
| @Override |
| protected void storeNonDiscard() { |
| super.storeNonDiscard(); |
| if (isPostfix) { |
| new OptimisticOperation(unaryNode, typeBounds) { |
| @Override |
| void loadStack() { |
| loadMinusOne(); |
| } |
| @Override |
| void consumeStack() { |
| doDecInc(getProgramPoint()); |
| } |
| }.emit(1); // 1 for non-incremented result on the top of the stack pushed in evaluate() |
| } |
| } |
| |
| private void loadMinusOne() { |
| if (type.isInteger()) { |
| method.load(isIncrement ? 1 : -1); |
| } else if (type.isLong()) { |
| method.load(isIncrement ? 1L : -1L); |
| } else { |
| method.load(isIncrement ? 1.0 : -1.0); |
| } |
| } |
| |
| private void doDecInc(final int programPoint) { |
| method.add(programPoint); |
| } |
| }.store(); |
| } |
| |
| private static int getOptimisticIgnoreCountForSelfModifyingExpression(final Expression target) { |
| return target instanceof AccessNode ? 1 : target instanceof IndexNode ? 2 : 0; |
| } |
| |
| private void loadAndDiscard(final Expression expr) { |
| // TODO: move checks for discarding to actual expression load code (e.g. as we do with void). That way we might |
| // be able to eliminate even more checks. |
| if(expr instanceof PrimitiveLiteralNode | isLocalVariable(expr)) { |
| assert !lc.isCurrentDiscard(expr); |
| // Don't bother evaluating expressions without side effects. Typical usage is "void 0" for reliably generating |
| // undefined. |
| return; |
| } |
| |
| lc.pushDiscard(expr); |
| loadExpression(expr, TypeBounds.UNBOUNDED); |
| if (lc.popDiscardIfCurrent(expr)) { |
| assert !expr.isAssignment(); |
| // NOTE: if we had a way to load with type void, we could avoid popping |
| method.pop(); |
| } |
| } |
| |
| /** |
| * Loads the expression with the specified type bounds, but if the parent expression is the current discard, |
| * then instead loads and discards the expression. |
| * @param parent the parent expression that's tested for being the current discard |
| * @param expr the expression that's either normally loaded or discard-loaded |
| * @param resultBounds result bounds for when loading the expression normally |
| */ |
| private void loadMaybeDiscard(final Expression parent, final Expression expr, final TypeBounds resultBounds) { |
| loadMaybeDiscard(lc.popDiscardIfCurrent(parent), expr, resultBounds); |
| } |
| |
| /** |
| * Loads the expression with the specified type bounds, or loads and discards the expression, depending on the |
| * value of the discard flag. Useful as a helper for expressions with control flow where you often can't combine |
| * testing for being the current discard and loading the subexpressions. |
| * @param discard if true, the expression is loaded and discarded |
| * @param expr the expression that's either normally loaded or discard-loaded |
| * @param resultBounds result bounds for when loading the expression normally |
| */ |
| private void loadMaybeDiscard(final boolean discard, final Expression expr, final TypeBounds resultBounds) { |
| if (discard) { |
| loadAndDiscard(expr); |
| } else { |
| loadExpression(expr, resultBounds); |
| } |
| } |
| |
| private void loadNEW(final UnaryNode unaryNode) { |
| final CallNode callNode = (CallNode)unaryNode.getExpression(); |
| final List<Expression> args = callNode.getArgs(); |
| |
| final Expression func = callNode.getFunction(); |
| // Load function reference. |
| loadExpressionAsObject(func); // must detect type error |
| |
| method.dynamicNew(1 + loadArgs(args), getCallSiteFlags(), func.toString(false)); |
| } |
| |
| private void loadNOT(final UnaryNode unaryNode) { |
| final Expression expr = unaryNode.getExpression(); |
| if(expr instanceof UnaryNode && expr.isTokenType(TokenType.NOT)) { |
| // !!x is idiomatic boolean cast in JavaScript |
| loadExpressionAsBoolean(((UnaryNode)expr).getExpression()); |
| } else { |
| final Label trueLabel = new Label("true"); |
| final Label afterLabel = new Label("after"); |
| |
| emitBranch(expr, trueLabel, true); |
| method.load(true); |
| method._goto(afterLabel); |
| method.label(trueLabel); |
| method.load(false); |
| method.label(afterLabel); |
| } |
| } |
| |
| private void loadSUB(final UnaryNode unaryNode, final TypeBounds resultBounds) { |
| final Type type = unaryNode.getType(); |
| assert type.isNumeric(); |
| final TypeBounds numericBounds = resultBounds.booleanToInt(); |
| new OptimisticOperation(unaryNode, numericBounds) { |
| @Override |
| void loadStack() { |
| final Expression expr = unaryNode.getExpression(); |
| loadExpression(expr, numericBounds.notWiderThan(Type.NUMBER)); |
| } |
| @Override |
| void consumeStack() { |
| // Must do an explicit conversion to the operation's type when it's double so that we correctly handle |
| // negation of an int 0 to a double -0. With this, we get the correct negation of a local variable after |
| // it deoptimized, e.g. "iload_2; i2d; dneg". Without this, we get "iload_2; ineg; i2d". |
| if(type.isNumber()) { |
| method.convert(type); |
| } |
| method.neg(getProgramPoint()); |
| } |
| }.emit(); |
| } |
| |
| public void loadVOID(final UnaryNode unaryNode, final TypeBounds resultBounds) { |
| loadAndDiscard(unaryNode.getExpression()); |
| if (!lc.popDiscardIfCurrent(unaryNode)) { |
| method.loadUndefined(resultBounds.widest); |
| } |
| } |
| |
| public void loadADD(final BinaryNode binaryNode, final TypeBounds resultBounds) { |
| new OptimisticOperation(binaryNode, resultBounds) { |
| @Override |
| void loadStack() { |
| final TypeBounds operandBounds; |
| final boolean isOptimistic = isValid(getProgramPoint()); |
| boolean forceConversionSeparation = false; |
| if(isOptimistic) { |
| operandBounds = new TypeBounds(binaryNode.getType(), Type.OBJECT); |
| } else { |
| // Non-optimistic, non-FP +. Allow it to overflow. |
| final Type widestOperationType = binaryNode.getWidestOperationType(); |
| operandBounds = new TypeBounds(Type.narrowest(binaryNode.getWidestOperandType(), resultBounds.widest), widestOperationType); |
| forceConversionSeparation = widestOperationType.narrowerThan(resultBounds.widest); |
| } |
| loadBinaryOperands(binaryNode.lhs(), binaryNode.rhs(), operandBounds, false, forceConversionSeparation); |
| } |
| |
| @Override |
| void consumeStack() { |
| method.add(getProgramPoint()); |
| } |
| }.emit(); |
| } |
| |
| private void loadAND_OR(final BinaryNode binaryNode, final TypeBounds resultBounds, final boolean isAnd) { |
| final Type narrowestOperandType = Type.widestReturnType(binaryNode.lhs().getType(), binaryNode.rhs().getType()); |
| |
| final boolean isCurrentDiscard = lc.popDiscardIfCurrent(binaryNode); |
| |
| final Label skip = new Label("skip"); |
| if(narrowestOperandType == Type.BOOLEAN) { |
| // optimize all-boolean logical expressions |
| final Label onTrue = new Label("andor_true"); |
| emitBranch(binaryNode, onTrue, true); |
| if (isCurrentDiscard) { |
| method.label(onTrue); |
| } else { |
| method.load(false); |
| method._goto(skip); |
| method.label(onTrue); |
| method.load(true); |
| method.label(skip); |
| } |
| return; |
| } |
| |
| final TypeBounds outBounds = resultBounds.notNarrowerThan(narrowestOperandType); |
| final JoinPredecessorExpression lhs = (JoinPredecessorExpression)binaryNode.lhs(); |
| final boolean lhsConvert = LocalVariableConversion.hasLiveConversion(lhs); |
| final Label evalRhs = lhsConvert ? new Label("eval_rhs") : null; |
| |
| loadExpression(lhs, outBounds); |
| if (!isCurrentDiscard) { |
| method.dup(); |
| } |
| method.convert(Type.BOOLEAN); |
| if (isAnd) { |
| if(lhsConvert) { |
| method.ifne(evalRhs); |
| } else { |
| method.ifeq(skip); |
| } |
| } else if(lhsConvert) { |
| method.ifeq(evalRhs); |
| } else { |
| method.ifne(skip); |
| } |
| |
| if(lhsConvert) { |
| method.beforeJoinPoint(lhs); |
| method._goto(skip); |
| method.label(evalRhs); |
| } |
| |
| if (!isCurrentDiscard) { |
| method.pop(); |
| } |
| final JoinPredecessorExpression rhs = (JoinPredecessorExpression)binaryNode.rhs(); |
| loadMaybeDiscard(isCurrentDiscard, rhs, outBounds); |
| method.beforeJoinPoint(rhs); |
| method.label(skip); |
| } |
| |
| private static boolean isLocalVariable(final Expression lhs) { |
| return lhs instanceof IdentNode && isLocalVariable((IdentNode)lhs); |
| } |
| |
| private static boolean isLocalVariable(final IdentNode lhs) { |
| return lhs.getSymbol().isBytecodeLocal(); |
| } |
| |
| // NOTE: does not use resultBounds as the assignment is driven by the type of the RHS |
| private void loadASSIGN(final BinaryNode binaryNode) { |
| final Expression lhs = binaryNode.lhs(); |
| final Expression rhs = binaryNode.rhs(); |
| |
| final Type rhsType = rhs.getType(); |
| // Detect dead assignments |
| if(lhs instanceof IdentNode) { |
| final Symbol symbol = ((IdentNode)lhs).getSymbol(); |
| if(!symbol.isScope() && !symbol.hasSlotFor(rhsType) && lc.popDiscardIfCurrent(binaryNode)) { |
| loadAndDiscard(rhs); |
| method.markDeadLocalVariable(symbol); |
| return; |
| } |
| } |
| |
| new Store<BinaryNode>(binaryNode, lhs) { |
| @Override |
| protected void evaluate() { |
| // NOTE: we're loading with "at least as wide as" so optimistic operations on the right hand side |
| // remain optimistic, and then explicitly convert to the required type if needed. |
| loadExpressionAsType(rhs, rhsType); |
| } |
| }.store(); |
| } |
| |
| /** |
| * Binary self-assignment that can be optimistic: +=, -=, *=, and /=. |
| */ |
| private abstract class BinaryOptimisticSelfAssignment extends SelfModifyingStore<BinaryNode> { |
| |
| /** |
| * Constructor |
| * |
| * @param node the assign op node |
| */ |
| BinaryOptimisticSelfAssignment(final BinaryNode node) { |
| super(node, node.lhs()); |
| } |
| |
| protected abstract void op(OptimisticOperation oo); |
| |
| @Override |
| protected void evaluate() { |
| final Expression lhs = assignNode.lhs(); |
| final Expression rhs = assignNode.rhs(); |
| final Type widestOperationType = assignNode.getWidestOperationType(); |
| final TypeBounds bounds = new TypeBounds(assignNode.getType(), widestOperationType); |
| new OptimisticOperation(assignNode, bounds) { |
| @Override |
| void loadStack() { |
| final boolean forceConversionSeparation; |
| if (isValid(getProgramPoint()) || widestOperationType == Type.NUMBER) { |
| forceConversionSeparation = false; |
| } else { |
| final Type operandType = Type.widest(booleanToInt(objectToNumber(lhs.getType())), booleanToInt(objectToNumber(rhs.getType()))); |
| forceConversionSeparation = operandType.narrowerThan(widestOperationType); |
| } |
| loadBinaryOperands(lhs, rhs, bounds, true, forceConversionSeparation); |
| } |
| @Override |
| void consumeStack() { |
| op(this); |
| } |
| }.emit(getOptimisticIgnoreCountForSelfModifyingExpression(lhs)); |
| method.convert(assignNode.getType()); |
| } |
| } |
| |
| /** |
| * Non-optimistic binary self-assignment operation. Basically, everything except +=, -=, *=, and /=. |
| */ |
| private abstract class BinarySelfAssignment extends SelfModifyingStore<BinaryNode> { |
| BinarySelfAssignment(final BinaryNode node) { |
| super(node, node.lhs()); |
| } |
| |
| protected abstract void op(); |
| |
| @Override |
| protected void evaluate() { |
| loadBinaryOperands(assignNode.lhs(), assignNode.rhs(), TypeBounds.UNBOUNDED.notWiderThan(assignNode.getWidestOperandType()), true, false); |
| op(); |
| } |
| } |
| |
| private void loadASSIGN_ADD(final BinaryNode binaryNode) { |
| new BinaryOptimisticSelfAssignment(binaryNode) { |
| @Override |
| protected void op(final OptimisticOperation oo) { |
| assert !(binaryNode.getType().isObject() && oo.isOptimistic); |
| method.add(oo.getProgramPoint()); |
| } |
| }.store(); |
| } |
| |
| private void loadASSIGN_BIT_AND(final BinaryNode binaryNode) { |
| new BinarySelfAssignment(binaryNode) { |
| @Override |
| protected void op() { |
| method.and(); |
| } |
| }.store(); |
| } |
| |
| private void loadASSIGN_BIT_OR(final BinaryNode binaryNode) { |
| new BinarySelfAssignment(binaryNode) { |
| @Override |
| protected void op() { |
| method.or(); |
| } |
| }.store(); |
| } |
| |
| private void loadASSIGN_BIT_XOR(final BinaryNode binaryNode) { |
| new BinarySelfAssignment(binaryNode) { |
| @Override |
| protected void op() { |
| method.xor(); |
| } |
| }.store(); |
| } |
| |
| private void loadASSIGN_DIV(final BinaryNode binaryNode) { |
| new BinaryOptimisticSelfAssignment(binaryNode) { |
| @Override |
| protected void op(final OptimisticOperation oo) { |
| method.div(oo.getProgramPoint()); |
| } |
| }.store(); |
| } |
| |
| private void loadASSIGN_MOD(final BinaryNode binaryNode) { |
| new BinaryOptimisticSelfAssignment(binaryNode) { |
| @Override |
| protected void op(final OptimisticOperation oo) { |
| method.rem(oo.getProgramPoint()); |
| } |
| }.store(); |
| } |
| |
| private void loadASSIGN_MUL(final BinaryNode binaryNode) { |
| new BinaryOptimisticSelfAssignment(binaryNode) { |
| @Override |
| protected void op(final OptimisticOperation oo) { |
| method.mul(oo.getProgramPoint()); |
| } |
| }.store(); |
| } |
| |
| private void loadASSIGN_SAR(final BinaryNode binaryNode) { |
| new BinarySelfAssignment(binaryNode) { |
| @Override |
| protected void op() { |
| method.sar(); |
| } |
| }.store(); |
| } |
| |
| private void loadASSIGN_SHL(final BinaryNode binaryNode) { |
| new BinarySelfAssignment(binaryNode) { |
| @Override |
| protected void op() { |
| method.shl(); |
| } |
| }.store(); |
| } |
| |
| private void loadASSIGN_SHR(final BinaryNode binaryNode) { |
| new BinarySelfAssignment(binaryNode) { |
| @Override |
| protected void op() { |
| doSHR(); |
| } |
| |
| }.store(); |
| } |
| |
| private void doSHR() { |
| // TODO: make SHR optimistic |
| method.shr(); |
| toUint(); |
| } |
| |
| private void toUint() { |
| JSType.TO_UINT32_I.invoke(method); |
| } |
| |
| private void loadASSIGN_SUB(final BinaryNode binaryNode) { |
| new BinaryOptimisticSelfAssignment(binaryNode) { |
| @Override |
| protected void op(final OptimisticOperation oo) { |
| method.sub(oo.getProgramPoint()); |
| } |
| }.store(); |
| } |
| |
| /** |
| * Helper class for binary arithmetic ops |
| */ |
| private abstract class BinaryArith { |
| protected abstract void op(int programPoint); |
| |
| protected void evaluate(final BinaryNode node, final TypeBounds resultBounds) { |
| final TypeBounds numericBounds = resultBounds.booleanToInt().objectToNumber(); |
| new OptimisticOperation(node, numericBounds) { |
| @Override |
| void loadStack() { |
| final TypeBounds operandBounds; |
| boolean forceConversionSeparation = false; |
| if(numericBounds.narrowest == Type.NUMBER) { |
| // Result should be double always. Propagate it into the operands so we don't have lots of I2D |
| // and L2D after operand evaluation. |
| assert numericBounds.widest == Type.NUMBER; |
| operandBounds = numericBounds; |
| } else { |
| final boolean isOptimistic = isValid(getProgramPoint()); |
| if(isOptimistic || node.isTokenType(TokenType.DIV) || node.isTokenType(TokenType.MOD)) { |
| operandBounds = new TypeBounds(node.getType(), Type.NUMBER); |
| } else { |
| // Non-optimistic, non-FP subtraction or multiplication. Allow them to overflow. |
| operandBounds = new TypeBounds(Type.narrowest(node.getWidestOperandType(), |
| numericBounds.widest), Type.NUMBER); |
| forceConversionSeparation = node.getWidestOperationType().narrowerThan(numericBounds.widest); |
| } |
| } |
| loadBinaryOperands(node.lhs(), node.rhs(), operandBounds, false, forceConversionSeparation); |
| } |
| |
| @Override |
| void consumeStack() { |
| op(getProgramPoint()); |
| } |
| }.emit(); |
| } |
| } |
| |
| private void loadBIT_AND(final BinaryNode binaryNode) { |
| loadBinaryOperands(binaryNode); |
| method.and(); |
| } |
| |
| private void loadBIT_OR(final BinaryNode binaryNode) { |
| // Optimize x|0 to (int)x |
| if (isRhsZero(binaryNode)) { |
| loadExpressionAsType(binaryNode.lhs(), Type.INT); |
| } else { |
| loadBinaryOperands(binaryNode); |
| method.or(); |
| } |
| } |
| |
| private static boolean isRhsZero(final BinaryNode binaryNode) { |
| final Expression rhs = binaryNode.rhs(); |
| return rhs instanceof LiteralNode && INT_ZERO.equals(((LiteralNode<?>)rhs).getValue()); |
| } |
| |
| private void loadBIT_XOR(final BinaryNode binaryNode) { |
| loadBinaryOperands(binaryNode); |
| method.xor(); |
| } |
| |
| private void loadCOMMARIGHT(final BinaryNode binaryNode, final TypeBounds resultBounds) { |
| loadAndDiscard(binaryNode.lhs()); |
| loadMaybeDiscard(binaryNode, binaryNode.rhs(), resultBounds); |
| } |
| |
| private void loadCOMMALEFT(final BinaryNode binaryNode, final TypeBounds resultBounds) { |
| loadMaybeDiscard(binaryNode, binaryNode.lhs(), resultBounds); |
| loadAndDiscard(binaryNode.rhs()); |
| } |
| |
| private void loadDIV(final BinaryNode binaryNode, final TypeBounds resultBounds) { |
| new BinaryArith() { |
| @Override |
| protected void op(final int programPoint) { |
| method.div(programPoint); |
| } |
| }.evaluate(binaryNode, resultBounds); |
| } |
| |
| private void loadCmp(final BinaryNode binaryNode, final Condition cond) { |
| loadComparisonOperands(binaryNode); |
| |
| final Label trueLabel = new Label("trueLabel"); |
| final Label afterLabel = new Label("skip"); |
| |
| method.conditionalJump(cond, trueLabel); |
| |
| method.load(Boolean.FALSE); |
| method._goto(afterLabel); |
| method.label(trueLabel); |
| method.load(Boolean.TRUE); |
| method.label(afterLabel); |
| } |
| |
| private void loadMOD(final BinaryNode binaryNode, final TypeBounds resultBounds) { |
| new BinaryArith() { |
| @Override |
| protected void op(final int programPoint) { |
| method.rem(programPoint); |
| } |
| }.evaluate(binaryNode, resultBounds); |
| } |
| |
| private void loadMUL(final BinaryNode binaryNode, final TypeBounds resultBounds) { |
| new BinaryArith() { |
| @Override |
| protected void op(final int programPoint) { |
| method.mul(programPoint); |
| } |
| }.evaluate(binaryNode, resultBounds); |
| } |
| |
| private void loadSAR(final BinaryNode binaryNode) { |
| loadBinaryOperands(binaryNode); |
| method.sar(); |
| } |
| |
| private void loadSHL(final BinaryNode binaryNode) { |
| loadBinaryOperands(binaryNode); |
| method.shl(); |
| } |
| |
| private void loadSHR(final BinaryNode binaryNode) { |
| // Optimize x >>> 0 to (uint)x |
| if (isRhsZero(binaryNode)) { |
| loadExpressionAsType(binaryNode.lhs(), Type.INT); |
| toUint(); |
| } else { |
| loadBinaryOperands(binaryNode); |
| doSHR(); |
| } |
| } |
| |
| private void loadSUB(final BinaryNode binaryNode, final TypeBounds resultBounds) { |
| new BinaryArith() { |
| @Override |
| protected void op(final int programPoint) { |
| method.sub(programPoint); |
| } |
| }.evaluate(binaryNode, resultBounds); |
| } |
| |
| @Override |
| public boolean enterLabelNode(final LabelNode labelNode) { |
| labeledBlockBreakLiveLocals.push(lc.getUsedSlotCount()); |
| return true; |
| } |
| |
| @Override |
| protected boolean enterDefault(final Node node) { |
| throw new AssertionError("Code generator entered node of type " + node.getClass().getName()); |
| } |
| |
| private void loadTernaryNode(final TernaryNode ternaryNode, final TypeBounds resultBounds) { |
| final Expression test = ternaryNode.getTest(); |
| final JoinPredecessorExpression trueExpr = ternaryNode.getTrueExpression(); |
| final JoinPredecessorExpression falseExpr = ternaryNode.getFalseExpression(); |
| |
| final Label falseLabel = new Label("ternary_false"); |
| final Label exitLabel = new Label("ternary_exit"); |
| |
| final Type outNarrowest = Type.narrowest(resultBounds.widest, Type.generic(Type.widestReturnType(trueExpr.getType(), falseExpr.getType()))); |
| final TypeBounds outBounds = resultBounds.notNarrowerThan(outNarrowest); |
| |
| emitBranch(test, falseLabel, false); |
| |
| final boolean isCurrentDiscard = lc.popDiscardIfCurrent(ternaryNode); |
| loadMaybeDiscard(isCurrentDiscard, trueExpr.getExpression(), outBounds); |
| assert isCurrentDiscard || Type.generic(method.peekType()) == outBounds.narrowest; |
| method.beforeJoinPoint(trueExpr); |
| method._goto(exitLabel); |
| method.label(falseLabel); |
| loadMaybeDiscard(isCurrentDiscard, falseExpr.getExpression(), outBounds); |
| assert isCurrentDiscard || Type.generic(method.peekType()) == outBounds.narrowest; |
| method.beforeJoinPoint(falseExpr); |
| method.label(exitLabel); |
| } |
| |
| /** |
| * Generate all shared scope calls generated during codegen. |
| */ |
| void generateScopeCalls() { |
| for (final SharedScopeCall scopeAccess : lc.getScopeCalls()) { |
| scopeAccess.generateScopeCall(); |
| } |
| } |
| |
| /** |
| * Debug code used to print symbols |
| * |
| * @param block the block we are in |
| * @param function the function we are in |
| * @param ident identifier for block or function where applicable |
| */ |
| private void printSymbols(final Block block, final FunctionNode function, final String ident) { |
| if (compiler.getScriptEnvironment()._print_symbols || function.getFlag(FunctionNode.IS_PRINT_SYMBOLS)) { |
| final PrintWriter out = compiler.getScriptEnvironment().getErr(); |
| out.println("[BLOCK in '" + ident + "']"); |
| if (!block.printSymbols(out)) { |
| out.println("<no symbols>"); |
| } |
| out.println(); |
| } |
| } |
| |
| |
| /** |
| * The difference between a store and a self modifying store is that |
| * the latter may load part of the target on the stack, e.g. the base |
| * of an AccessNode or the base and index of an IndexNode. These are used |
| * both as target and as an extra source. Previously it was problematic |
| * for self modifying stores if the target/lhs didn't belong to one |
| * of three trivial categories: IdentNode, AcessNodes, IndexNodes. In that |
| * case it was evaluated and tagged as "resolved", which meant at the second |
| * time the lhs of this store was read (e.g. in a = a (second) + b for a += b, |
| * it would be evaluated to a nop in the scope and cause stack underflow |
| * |
| * see NASHORN-703 |
| * |
| * @param <T> |
| */ |
| private abstract class SelfModifyingStore<T extends Expression> extends Store<T> { |
| protected SelfModifyingStore(final T assignNode, final Expression target) { |
| super(assignNode, target); |
| } |
| |
| @Override |
| protected boolean isSelfModifying() { |
| return true; |
| } |
| } |
| |
| /** |
| * Helper class to generate stores |
| */ |
| private abstract class Store<T extends Expression> { |
| |
| /** An assignment node, e.g. x += y */ |
| protected final T assignNode; |
| |
| /** The target node to store to, e.g. x */ |
| private final Expression target; |
| |
| /** How deep on the stack do the arguments go if this generates an indy call */ |
| private int depth; |
| |
| /** If we have too many arguments, we need temporary storage, this is stored in 'quick' */ |
| private IdentNode quick; |
| |
| /** |
| * Constructor |
| * |
| * @param assignNode the node representing the whole assignment |
| * @param target the target node of the assignment (destination) |
| */ |
| protected Store(final T assignNode, final Expression target) { |
| this.assignNode = assignNode; |
| this.target = target; |
| } |
| |
| /** |
| * Constructor |
| * |
| * @param assignNode the node representing the whole assignment |
| */ |
| protected Store(final T assignNode) { |
| this(assignNode, assignNode); |
| } |
| |
| /** |
| * Is this a self modifying store operation, e.g. *= or ++ |
| * @return true if self modifying store |
| */ |
| protected boolean isSelfModifying() { |
| return false; |
| } |
| |
| private void prologue() { |
| /* |
| * This loads the parts of the target, e.g base and index. they are kept |
| * on the stack throughout the store and used at the end to execute it |
| */ |
| |
| target.accept(new SimpleNodeVisitor() { |
| @Override |
| public boolean enterIdentNode(final IdentNode node) { |
| if (node.getSymbol().isScope()) { |
| method.loadCompilerConstant(SCOPE); |
| depth += Type.SCOPE.getSlots(); |
| assert depth == 1; |
| } |
| return false; |
| } |
| |
| private void enterBaseNode() { |
| assert target instanceof BaseNode : "error - base node " + target + " must be instanceof BaseNode"; |
| final BaseNode baseNode = (BaseNode)target; |
| final Expression base = baseNode.getBase(); |
| |
| loadExpressionAsObject(base); |
| depth += Type.OBJECT.getSlots(); |
| assert depth == 1; |
| |
| if (isSelfModifying()) { |
| method.dup(); |
| } |
| } |
| |
| @Override |
| public boolean enterAccessNode(final AccessNode node) { |
| enterBaseNode(); |
| return false; |
| } |
| |
| @Override |
| public boolean enterIndexNode(final IndexNode node) { |
| enterBaseNode(); |
| |
| final Expression index = node.getIndex(); |
| if (!index.getType().isNumeric()) { |
| // could be boolean here as well |
| loadExpressionAsObject(index); |
| } else { |
| loadExpressionUnbounded(index); |
| } |
| depth += index.getType().getSlots(); |
| |
| if (isSelfModifying()) { |
| //convert "base base index" to "base index base index" |
| method.dup(1); |
| } |
| |
| return false; |
| } |
| |
| }); |
| } |
| |
| /** |
| * Generates an extra local variable, always using the same slot, one that is available after the end of the |
| * frame. |
| * |
| * @param type the type of the variable |
| * |
| * @return the quick variable |
| */ |
| private IdentNode quickLocalVariable(final Type type) { |
| final String name = lc.getCurrentFunction().uniqueName(QUICK_PREFIX.symbolName()); |
| final Symbol symbol = new Symbol(name, IS_INTERNAL | HAS_SLOT); |
| symbol.setHasSlotFor(type); |
| symbol.setFirstSlot(lc.quickSlot(type)); |
| |
| final IdentNode quickIdent = IdentNode.createInternalIdentifier(symbol).setType(type); |
| |
| return quickIdent; |
| } |
| |
| // store the result that "lives on" after the op, e.g. "i" in i++ postfix. |
| protected void storeNonDiscard() { |
| if (lc.popDiscardIfCurrent(assignNode)) { |
| assert assignNode.isAssignment(); |
| return; |
| } |
| |
| if (method.dup(depth) == null) { |
| method.dup(); |
| final Type quickType = method.peekType(); |
| this.quick = quickLocalVariable(quickType); |
| final Symbol quickSymbol = quick.getSymbol(); |
| method.storeTemp(quickType, quickSymbol.getFirstSlot()); |
| } |
| } |
| |
| private void epilogue() { |
| /** |
| * Take the original target args from the stack and use them |
| * together with the value to be stored to emit the store code |
| * |
| * The case that targetSymbol is in scope (!hasSlot) and we actually |
| * need to do a conversion on non-equivalent types exists, but is |
| * very rare. See for example test/script/basic/access-specializer.js |
| */ |
| target.accept(new SimpleNodeVisitor() { |
| @Override |
| protected boolean enterDefault(final Node node) { |
| throw new AssertionError("Unexpected node " + node + " in store epilogue"); |
| } |
| |
| @Override |
| public boolean enterIdentNode(final IdentNode node) { |
| final Symbol symbol = node.getSymbol(); |
| assert symbol != null; |
| if (symbol.isScope()) { |
| final int flags = getScopeCallSiteFlags(symbol); |
| if (isFastScope(symbol)) { |
| storeFastScopeVar(symbol, flags); |
| } else { |
| method.dynamicSet(node.getName(), flags, false); |
| } |
| } else { |
| final Type storeType = assignNode.getType(); |
| if (symbol.hasSlotFor(storeType)) { |
| // Only emit a convert for a store known to be live; converts for dead stores can |
| // give us an unnecessary ClassCastException. |
| method.convert(storeType); |
| } |
| storeIdentWithCatchConversion(node, storeType); |
| } |
| return false; |
| |
| } |
| |
| @Override |
| public boolean enterAccessNode(final AccessNode node) { |
| method.dynamicSet(node.getProperty(), getCallSiteFlags(), node.isIndex()); |
| return false; |
| } |
| |
| @Override |
| public boolean enterIndexNode(final IndexNode node) { |
| method.dynamicSetIndex(getCallSiteFlags()); |
| return false; |
| } |
| }); |
| |
| |
| // whatever is on the stack now is the final answer |
| } |
| |
| protected abstract void evaluate(); |
| |
| void store() { |
| if (target instanceof IdentNode) { |
| checkTemporalDeadZone((IdentNode)target); |
| } |
| prologue(); |
| evaluate(); // leaves an operation of whatever the operationType was on the stack |
| storeNonDiscard(); |
| epilogue(); |
| if (quick != null) { |
| method.load(quick); |
| } |
| } |
| } |
| |
| private void newFunctionObject(final FunctionNode functionNode, final boolean addInitializer) { |
| assert lc.peek() == functionNode; |
| |
| final RecompilableScriptFunctionData data = compiler.getScriptFunctionData(functionNode.getId()); |
| |
| if (functionNode.isProgram() && !compiler.isOnDemandCompilation()) { |
| final MethodEmitter createFunction = functionNode.getCompileUnit().getClassEmitter().method( |
| EnumSet.of(Flag.PUBLIC, Flag.STATIC), CREATE_PROGRAM_FUNCTION.symbolName(), |
| ScriptFunction.class, ScriptObject.class); |
| createFunction.begin(); |
| loadConstantsAndIndex(data, createFunction); |
| createFunction.load(SCOPE_TYPE, 0); |
| createFunction.invoke(CREATE_FUNCTION_OBJECT); |
| createFunction._return(); |
| createFunction.end(); |
| } |
| |
| if (addInitializer && !compiler.isOnDemandCompilation()) { |
| functionNode.getCompileUnit().addFunctionInitializer(data, functionNode); |
| } |
| |
| // We don't emit a ScriptFunction on stack for the outermost compiled function (as there's no code being |
| // generated in its outer context that'd need it as a callee). |
| if (lc.getOutermostFunction() == functionNode) { |
| return; |
| } |
| |
| loadConstantsAndIndex(data, method); |
| |
| if (functionNode.needsParentScope()) { |
| method.loadCompilerConstant(SCOPE); |
| method.invoke(CREATE_FUNCTION_OBJECT); |
| } else { |
| method.invoke(CREATE_FUNCTION_OBJECT_NO_SCOPE); |
| } |
| } |
| |
| // calls on Global class. |
| private MethodEmitter globalInstance() { |
| return method.invokestatic(GLOBAL_OBJECT, "instance", "()L" + GLOBAL_OBJECT + ';'); |
| } |
| |
| private MethodEmitter globalAllocateArguments() { |
| return method.invokestatic(GLOBAL_OBJECT, "allocateArguments", methodDescriptor(ScriptObject.class, Object[].class, Object.class, int.class)); |
| } |
| |
| private MethodEmitter globalNewRegExp() { |
| return method.invokestatic(GLOBAL_OBJECT, "newRegExp", methodDescriptor(Object.class, String.class, String.class)); |
| } |
| |
| private MethodEmitter globalRegExpCopy() { |
| return method.invokestatic(GLOBAL_OBJECT, "regExpCopy", methodDescriptor(Object.class, Object.class)); |
| } |
| |
| private MethodEmitter globalAllocateArray(final ArrayType type) { |
| //make sure the native array is treated as an array type |
| return method.invokestatic(GLOBAL_OBJECT, "allocate", "(" + type.getDescriptor() + ")Ljdk/nashorn/internal/objects/NativeArray;"); |
| } |
| |
| private MethodEmitter globalIsEval() { |
| return method.invokestatic(GLOBAL_OBJECT, "isEval", methodDescriptor(boolean.class, Object.class)); |
| } |
| |
| private MethodEmitter globalReplaceLocationPropertyPlaceholder() { |
| return method.invokestatic(GLOBAL_OBJECT, "replaceLocationPropertyPlaceholder", methodDescriptor(Object.class, Object.class, Object.class)); |
| } |
| |
| private MethodEmitter globalCheckObjectCoercible() { |
| return method.invokestatic(GLOBAL_OBJECT, "checkObjectCoercible", methodDescriptor(void.class, Object.class)); |
| } |
| |
| private MethodEmitter globalDirectEval() { |
| return method.invokestatic(GLOBAL_OBJECT, "directEval", |
| methodDescriptor(Object.class, Object.class, Object.class, Object.class, Object.class, boolean.class)); |
| } |
| |
| private abstract class OptimisticOperation { |
| private final boolean isOptimistic; |
| // expression and optimistic are the same reference |
| private final Expression expression; |
| private final Optimistic optimistic; |
| private final TypeBounds resultBounds; |
| |
| OptimisticOperation(final Optimistic optimistic, final TypeBounds resultBounds) { |
| this.optimistic = optimistic; |
| this.expression = (Expression)optimistic; |
| this.resultBounds = resultBounds; |
| this.isOptimistic = isOptimistic(optimistic) && useOptimisticTypes() && |
| // Operation is only effectively optimistic if its type, after being coerced into the result bounds |
| // is narrower than the upper bound. |
| resultBounds.within(Type.generic(((Expression)optimistic).getType())).narrowerThan(resultBounds.widest); |
| } |
| |
| MethodEmitter emit() { |
| return emit(0); |
| } |
| |
| MethodEmitter emit(final int ignoredArgCount) { |
| final int programPoint = optimistic.getProgramPoint(); |
| final boolean optimisticOrContinuation = isOptimistic || isContinuationEntryPoint(programPoint); |
| final boolean currentContinuationEntryPoint = isCurrentContinuationEntryPoint(programPoint); |
| final int stackSizeOnEntry = method.getStackSize() - ignoredArgCount; |
| |
| // First store the values on the stack opportunistically into local variables. Doing it before loadStack() |
| // allows us to not have to pop/load any arguments that are pushed onto it by loadStack() in the second |
| // storeStack(). |
| storeStack(ignoredArgCount, optimisticOrContinuation); |
| |
| // Now, load the stack |
| loadStack(); |
| |
| // Now store the values on the stack ultimately into local variables. In vast majority of cases, this is |
| // (aside from creating the local types map) a no-op, as the first opportunistic stack store will already |
| // store all variables. However, there can be operations in the loadStack() that invalidate some of the |
| // stack stores, e.g. in "x[i] = x[++i]", "++i" will invalidate the already stored value for "i". In such |
| // unfortunate cases this second storeStack() will restore the invariant that everything on the stack is |
| // stored into a local variable, although at the cost of doing a store/load on the loaded arguments as well. |
| final int liveLocalsCount = storeStack(method.getStackSize() - stackSizeOnEntry, optimisticOrContinuation); |
| assert optimisticOrContinuation == (liveLocalsCount != -1); |
| |
| final Label beginTry; |
| final Label catchLabel; |
| final Label afterConsumeStack = isOptimistic || currentContinuationEntryPoint ? new Label("after_consume_stack") : null; |
| if(isOptimistic) { |
| beginTry = new Label("try_optimistic"); |
| final String catchLabelName = (afterConsumeStack == null ? "" : afterConsumeStack.toString()) + "_handler"; |
| catchLabel = new Label(catchLabelName); |
| method.label(beginTry); |
| } else { |
| beginTry = catchLabel = null; |
| } |
| |
| consumeStack(); |
| |
| if(isOptimistic) { |
| method._try(beginTry, afterConsumeStack, catchLabel, UnwarrantedOptimismException.class); |
| } |
| |
| if(isOptimistic || currentContinuationEntryPoint) { |
| method.label(afterConsumeStack); |
| |
| final int[] localLoads = method.getLocalLoadsOnStack(0, stackSizeOnEntry); |
| assert everyStackValueIsLocalLoad(localLoads) : Arrays.toString(localLoads) + ", " + stackSizeOnEntry + ", " + ignoredArgCount; |
| final List<Type> localTypesList = method.getLocalVariableTypes(); |
| final int usedLocals = method.getUsedSlotsWithLiveTemporaries(); |
| final List<Type> localTypes = method.getWidestLiveLocals(localTypesList.subList(0, usedLocals)); |
| assert everyLocalLoadIsValid(localLoads, usedLocals) : Arrays.toString(localLoads) + " ~ " + localTypes; |
| |
| if(isOptimistic) { |
| addUnwarrantedOptimismHandlerLabel(localTypes, catchLabel); |
| } |
| if(currentContinuationEntryPoint) { |
| final ContinuationInfo ci = getContinuationInfo(); |
| assert ci != null : "no continuation info found for " + lc.getCurrentFunction(); |
| assert !ci.hasTargetLabel(); // No duplicate program points |
| ci.setTargetLabel(afterConsumeStack); |
| ci.getHandlerLabel().markAsOptimisticContinuationHandlerFor(afterConsumeStack); |
| // Can't rely on targetLabel.stack.localVariableTypes.length, as it can be higher due to effectively |
| // dead local variables. |
| ci.lvarCount = localTypes.size(); |
| ci.setStackStoreSpec(localLoads); |
| ci.setStackTypes(Arrays.copyOf(method.getTypesFromStack(method.getStackSize()), stackSizeOnEntry)); |
| assert ci.getStackStoreSpec().length == ci.getStackTypes().length; |
| ci.setReturnValueType(method.peekType()); |
| ci.lineNumber = getLastLineNumber(); |
| ci.catchLabel = catchLabels.peek(); |
| } |
| } |
| return method; |
| } |
| |
| /** |
| * Stores the current contents of the stack into local variables so they are not lost before invoking something that |
| * can result in an {@code UnwarantedOptimizationException}. |
| * @param ignoreArgCount the number of topmost arguments on stack to ignore when deciding on the shape of the catch |
| * block. Those are used in the situations when we could not place the call to {@code storeStack} early enough |
| * (before emitting code for pushing the arguments that the optimistic call will pop). This is admittedly a |
| * deficiency in the design of the code generator when it deals with self-assignments and we should probably look |
| * into fixing it. |
| * @return types of the significant local variables after the stack was stored (types for local variables used |
| * for temporary storage of ignored arguments are not returned). |
| * @param optimisticOrContinuation if false, this method should not execute |
| * a label for a catch block for the {@code UnwarantedOptimizationException}, suitable for capturing the |
| * currently live local variables, tailored to their types. |
| */ |
| private int storeStack(final int ignoreArgCount, final boolean optimisticOrContinuation) { |
| if(!optimisticOrContinuation) { |
| return -1; // NOTE: correct value to return is lc.getUsedSlotCount(), but it wouldn't be used anyway |
| } |
| |
| final int stackSize = method.getStackSize(); |
| final Type[] stackTypes = method.getTypesFromStack(stackSize); |
| final int[] localLoadsOnStack = method.getLocalLoadsOnStack(0, stackSize); |
| final int usedSlots = method.getUsedSlotsWithLiveTemporaries(); |
| |
| final int firstIgnored = stackSize - ignoreArgCount; |
| // Find the first value on the stack (from the bottom) that is not a load from a local variable. |
| int firstNonLoad = 0; |
| while(firstNonLoad < firstIgnored && localLoadsOnStack[firstNonLoad] != Label.Stack.NON_LOAD) { |
| firstNonLoad++; |
| } |
| |
| // Only do the store/load if first non-load is not an ignored argument. Otherwise, do nothing and return |
| // the number of used slots as the number of live local variables. |
| if(firstNonLoad >= firstIgnored) { |
| return usedSlots; |
| } |
| |
| // Find the number of new temporary local variables that we need; it's the number of values on the stack that |
| // are not direct loads of existing local variables. |
| int tempSlotsNeeded = 0; |
| for(int i = firstNonLoad; i < stackSize; ++i) { |
| if(localLoadsOnStack[i] == Label.Stack.NON_LOAD) { |
| tempSlotsNeeded += stackTypes[i].getSlots(); |
| } |
| } |
| |
| // Ensure all values on the stack that weren't directly loaded from a local variable are stored in a local |
| // variable. We're starting from highest local variable index, so that in case ignoreArgCount > 0 the ignored |
| // ones end up at the end of the local variable table. |
| int lastTempSlot = usedSlots + tempSlotsNeeded; |
| int ignoreSlotCount = 0; |
| for(int i = stackSize; i -- > firstNonLoad;) { |
| final int loadSlot = localLoadsOnStack[i]; |
| if(loadSlot == Label.Stack.NON_LOAD) { |
| final Type type = stackTypes[i]; |
| final int slots = type.getSlots(); |
| lastTempSlot -= slots; |
| if(i >= firstIgnored) { |
| ignoreSlotCount += slots; |
| } |
| method.storeTemp(type, lastTempSlot); |
| } else { |
| method.pop(); |
| } |
| } |
| assert lastTempSlot == usedSlots; // used all temporary locals |
| |
| final List<Type> localTypesList = method.getLocalVariableTypes(); |
| |
| // Load values back on stack. |
| for(int i = firstNonLoad; i < stackSize; ++i) { |
| final int loadSlot = localLoadsOnStack[i]; |
| final Type stackType = stackTypes[i]; |
| final boolean isLoad = loadSlot != Label.Stack.NON_LOAD; |
| final int lvarSlot = isLoad ? loadSlot : lastTempSlot; |
| final Type lvarType = localTypesList.get(lvarSlot); |
| method.load(lvarType, lvarSlot); |
| if(isLoad) { |
| // Conversion operators (I2L etc.) preserve "load"-ness of the value despite the fact that, in the |
| // strict sense they are creating a derived value from the loaded value. This special behavior of |
| // on-stack conversion operators is necessary to accommodate for differences in local variable types |
| // after deoptimization; having a conversion operator throw away "load"-ness would create different |
| // local variable table shapes between optimism-failed code and its deoptimized rest-of method). |
| // After we load the value back, we need to redo the conversion to the stack type if stack type is |
| // different. |
| // NOTE: this would only strictly be necessary for widening conversions (I2L, L2D, I2D), and not for |
| // narrowing ones (L2I, D2L, D2I) as only widening conversions are the ones that can get eliminated |
| // in a deoptimized method, as their original input argument got widened. Maybe experiment with |
| // throwing away "load"-ness for narrowing conversions in MethodEmitter.convert()? |
| method.convert(stackType); |
| } else { |
| // temporary stores never needs a convert, as their type is always the same as the stack type. |
| assert lvarType == stackType; |
| lastTempSlot += lvarType.getSlots(); |
| } |
| } |
| // used all temporaries |
| assert lastTempSlot == usedSlots + tempSlotsNeeded; |
| |
| return lastTempSlot - ignoreSlotCount; |
| } |
| |
| private void addUnwarrantedOptimismHandlerLabel(final List<Type> localTypes, final Label label) { |
| final String lvarTypesDescriptor = getLvarTypesDescriptor(localTypes); |
| final Map<String, Collection<Label>> unwarrantedOptimismHandlers = lc.getUnwarrantedOptimismHandlers(); |
| Collection<Label> labels = unwarrantedOptimismHandlers.get(lvarTypesDescriptor); |
| if(labels == null) { |
| labels = new LinkedList<>(); |
| unwarrantedOptimismHandlers.put(lvarTypesDescriptor, labels); |
| } |
| method.markLabelAsOptimisticCatchHandler(label, localTypes.size()); |
| labels.add(label); |
| } |
| |
| abstract void loadStack(); |
| |
| // Make sure that whatever indy call site you emit from this method uses {@code getCallSiteFlagsOptimistic(node)} |
| // or otherwise ensure optimistic flag is correctly set in the call site, otherwise it doesn't make much sense |
| // to use OptimisticExpression for emitting it. |
| abstract void consumeStack(); |
| |
| /** |
| * Emits the correct dynamic getter code. Normally just delegates to method emitter, except when the target |
| * expression is optimistic, and the desired type is narrower than the optimistic type. In that case, it'll emit a |
| * dynamic getter with its original optimistic type, and explicitly insert a narrowing conversion. This way we can |
| * preserve the optimism of the values even if they're subsequently immediately coerced into a narrower type. This |
| * is beneficial because in this case we can still presume that since the original getter was optimistic, the |
| * conversion has no side effects. |
| * @param name the name of the property being get |
| * @param flags call site flags |
| * @param isMethod whether we're preferably retrieving a function |
| * @return the current method emitter |
| */ |
| MethodEmitter dynamicGet(final String name, final int flags, final boolean isMethod, final boolean isIndex) { |
| if(isOptimistic) { |
| return method.dynamicGet(getOptimisticCoercedType(), name, getOptimisticFlags(flags), isMethod, isIndex); |
| } |
| return method.dynamicGet(resultBounds.within(expression.getType()), name, nonOptimisticFlags(flags), isMethod, isIndex); |
| } |
| |
| MethodEmitter dynamicGetIndex(final int flags, final boolean isMethod) { |
| if(isOptimistic) { |
| return method.dynamicGetIndex(getOptimisticCoercedType(), getOptimisticFlags(flags), isMethod); |
| } |
| return method.dynamicGetIndex(resultBounds.within(expression.getType()), nonOptimisticFlags(flags), isMethod); |
| } |
| |
| MethodEmitter dynamicCall(final int argCount, final int flags, final String msg) { |
| if (isOptimistic) { |
| return method.dynamicCall(getOptimisticCoercedType(), argCount, getOptimisticFlags(flags), msg); |
| } |
| return method.dynamicCall(resultBounds.within(expression.getType()), argCount, nonOptimisticFlags(flags), msg); |
| } |
| |
| int getOptimisticFlags(final int flags) { |
| return flags | CALLSITE_OPTIMISTIC | (optimistic.getProgramPoint() << CALLSITE_PROGRAM_POINT_SHIFT); //encode program point in high bits |
| } |
| |
| int getProgramPoint() { |
| return isOptimistic ? optimistic.getProgramPoint() : INVALID_PROGRAM_POINT; |
| } |
| |
| void convertOptimisticReturnValue() { |
| if (isOptimistic) { |
| final Type optimisticType = getOptimisticCoercedType(); |
| if(!optimisticType.isObject()) { |
| method.load(optimistic.getProgramPoint()); |
| if(optimisticType.isInteger()) { |
| method.invoke(ENSURE_INT); |
| } else if(optimisticType.isLong()) { |
| method.invoke(ENSURE_LONG); |
| } else if(optimisticType.isNumber()) { |
| method.invoke(ENSURE_NUMBER); |
| } else { |
| throw new AssertionError(optimisticType); |
| } |
| } |
| } |
| } |
| |
| void replaceCompileTimeProperty() { |
| final IdentNode identNode = (IdentNode)expression; |
| final String name = identNode.getSymbol().getName(); |
| if (CompilerConstants.__FILE__.name().equals(name)) { |
| replaceCompileTimeProperty(getCurrentSource().getName()); |
| } else if (CompilerConstants.__DIR__.name().equals(name)) { |
| replaceCompileTimeProperty(getCurrentSource().getBase()); |
| } else if (CompilerConstants.__LINE__.name().equals(name)) { |
| replaceCompileTimeProperty(getCurrentSource().getLine(identNode.position())); |
| } |
| } |
| |
| /** |
| * When an ident with name __FILE__, __DIR__, or __LINE__ is loaded, we'll try to look it up as any other |
| * identifier. However, if it gets all the way up to the Global object, it will send back a special value that |
| * represents a placeholder for these compile-time location properties. This method will generate code that loads |
| * the value of the compile-time location property and then invokes a method in Global that will replace the |
| * placeholder with the value. Effectively, if the symbol for these properties is defined anywhere in the lexical |
| * scope, they take precedence, but if they aren't, then they resolve to the compile-time location property. |
| * @param propertyValue the actual value of the property |
| */ |
| private void replaceCompileTimeProperty(final Object propertyValue) { |
| assert method.peekType().isObject(); |
| if(propertyValue instanceof String || propertyValue == null) { |
| method.load((String)propertyValue); |
| } else if(propertyValue instanceof Integer) { |
| method.load(((Integer)propertyValue)); |
| method.convert(Type.OBJECT); |
| } else { |
| throw new AssertionError(); |
| } |
| globalReplaceLocationPropertyPlaceholder(); |
| convertOptimisticReturnValue(); |
| } |
| |
| /** |
| * Returns the type that should be used as the return type of the dynamic invocation that is emitted as the code |
| * for the current optimistic operation. If the type bounds is exact boolean or narrower than the expression's |
| * optimistic type, then the optimistic type is returned, otherwise the coercing type. Effectively, this method |
| * allows for moving the coercion into the optimistic type when it won't adversely affect the optimistic |
| * evaluation semantics, and for preserving the optimistic type and doing a separate coercion when it would |
| * affect it. |
| * @return |
| */ |
| private Type getOptimisticCoercedType() { |
| final Type optimisticType = expression.getType(); |
| assert resultBounds.widest.widerThan(optimisticType); |
| final Type narrowest = resultBounds.narrowest; |
| |
| if(narrowest.isBoolean() || narrowest.narrowerThan(optimisticType)) { |
| assert !optimisticType.isObject(); |
| return optimisticType; |
| } |
| assert !narrowest.isObject(); |
| return narrowest; |
| } |
| } |
| |
| private static boolean isOptimistic(final Optimistic optimistic) { |
| if(!optimistic.canBeOptimistic()) { |
| return false; |
| } |
| final Expression expr = (Expression)optimistic; |
| return expr.getType().narrowerThan(expr.getWidestOperationType()); |
| } |
| |
| private static boolean everyLocalLoadIsValid(final int[] loads, final int localCount) { |
| for (final int load : loads) { |
| if(load < 0 || load >= localCount) { |
| return false; |
| } |
| } |
| return true; |
| } |
| |
| private static boolean everyStackValueIsLocalLoad(final int[] loads) { |
| for (final int load : loads) { |
| if(load == Label.Stack.NON_LOAD) { |
| return false; |
| } |
| } |
| return true; |
| } |
| |
| private String getLvarTypesDescriptor(final List<Type> localVarTypes) { |
| final int count = localVarTypes.size(); |
| final StringBuilder desc = new StringBuilder(count); |
| for(int i = 0; i < count;) { |
| i += appendType(desc, localVarTypes.get(i)); |
| } |
| return method.markSymbolBoundariesInLvarTypesDescriptor(desc.toString()); |
| } |
| |
| private static int appendType(final StringBuilder b, final Type t) { |
| b.append(t.getBytecodeStackType()); |
| return t.getSlots(); |
| } |
| |
| private static int countSymbolsInLvarTypeDescriptor(final String lvarTypeDescriptor) { |
| int count = 0; |
| for(int i = 0; i < lvarTypeDescriptor.length(); ++i) { |
| if(Character.isUpperCase(lvarTypeDescriptor.charAt(i))) { |
| ++count; |
| } |
| } |
| return count; |
| |
| } |
| /** |
| * Generates all the required {@code UnwarrantedOptimismException} handlers for the current function. The employed |
| * strategy strives to maximize code reuse. Every handler constructs an array to hold the local variables, then |
| * fills in some trailing part of the local variables (those for which it has a unique suffix in the descriptor), |
| * then jumps to a handler for a prefix that's shared with other handlers. A handler that fills up locals up to |
| * position 0 will not jump to a prefix handler (as it has no prefix), but instead end with constructing and |
| * throwing a {@code RewriteException}. Since we lexicographically sort the entries, we only need to check every |
| * entry to its immediately preceding one for longest matching prefix. |
| * @return true if there is at least one exception handler |
| */ |
| private boolean generateUnwarrantedOptimismExceptionHandlers(final FunctionNode fn) { |
| if(!useOptimisticTypes()) { |
| return false; |
| } |
| |
| // Take the mapping of lvarSpecs -> labels, and turn them into a descending lexicographically sorted list of |
| // handler specifications. |
| final Map<String, Collection<Label>> unwarrantedOptimismHandlers = lc.popUnwarrantedOptimismHandlers(); |
| if(unwarrantedOptimismHandlers.isEmpty()) { |
| return false; |
| } |
| |
| method.lineNumber(0); |
| |
| final List<OptimismExceptionHandlerSpec> handlerSpecs = new ArrayList<>(unwarrantedOptimismHandlers.size() * 4/3); |
| for(final String spec: unwarrantedOptimismHandlers.keySet()) { |
| handlerSpecs.add(new OptimismExceptionHandlerSpec(spec, true)); |
| } |
| Collections.sort(handlerSpecs, Collections.reverseOrder()); |
| |
| // Map of local variable specifications to labels for populating the array for that local variable spec. |
| final Map<String, Label> delegationLabels = new HashMap<>(); |
| |
| // Do everything in a single pass over the handlerSpecs list. Note that the list can actually grow as we're |
| // passing through it as we might add new prefix handlers into it, so can't hoist size() outside of the loop. |
| for(int handlerIndex = 0; handlerIndex < handlerSpecs.size(); ++handlerIndex) { |
| final OptimismExceptionHandlerSpec spec = handlerSpecs.get(handlerIndex); |
| final String lvarSpec = spec.lvarSpec; |
| if(spec.catchTarget) { |
| assert !method.isReachable(); |
| // Start a catch block and assign the labels for this lvarSpec with it. |
| method._catch(unwarrantedOptimismHandlers.get(lvarSpec)); |
| // This spec is a catch target, so emit array creation code. The length of the array is the number of |
| // symbols - the number of uppercase characters. |
| method.load(countSymbolsInLvarTypeDescriptor(lvarSpec)); |
| method.newarray(Type.OBJECT_ARRAY); |
| } |
| if(spec.delegationTarget) { |
| // If another handler can delegate to this handler as its prefix, then put a jump target here for the |
| // shared code (after the array creation code, which is never shared). |
| method.label(delegationLabels.get(lvarSpec)); // label must exist |
| } |
| |
| final boolean lastHandler = handlerIndex == handlerSpecs.size() - 1; |
| |
| int lvarIndex; |
| final int firstArrayIndex; |
| final int firstLvarIndex; |
| Label delegationLabel; |
| final String commonLvarSpec; |
| if(lastHandler) { |
| // Last handler block, doesn't delegate to anything. |
| lvarIndex = 0; |
| firstLvarIndex = 0; |
| firstArrayIndex = 0; |
| delegationLabel = null; |
| commonLvarSpec = null; |
| } else { |
| // Not yet the last handler block, will definitely delegate to another handler; let's figure out which |
| // one. It can be an already declared handler further down the list, or it might need to declare a new |
| // prefix handler. |
| |
| // Since we're lexicographically ordered, the common prefix handler is defined by the common prefix of |
| // this handler and the next handler on the list. |
| final int nextHandlerIndex = handlerIndex + 1; |
| final String nextLvarSpec = handlerSpecs.get(nextHandlerIndex).lvarSpec; |
| commonLvarSpec = commonPrefix(lvarSpec, nextLvarSpec); |
| // We don't chop symbols in half |
| assert Character.isUpperCase(commonLvarSpec.charAt(commonLvarSpec.length() - 1)); |
| |
| // Let's find if we already have a declaration for such handler, or we need to insert it. |
| { |
| boolean addNewHandler = true; |
| int commonHandlerIndex = nextHandlerIndex; |
| for(; commonHandlerIndex < handlerSpecs.size(); ++commonHandlerIndex) { |
| final OptimismExceptionHandlerSpec forwardHandlerSpec = handlerSpecs.get(commonHandlerIndex); |
| final String forwardLvarSpec = forwardHandlerSpec.lvarSpec; |
| if(forwardLvarSpec.equals(commonLvarSpec)) { |
| // We already have a handler for the common prefix. |
| addNewHandler = false; |
| // Make sure we mark it as a delegation target. |
| forwardHandlerSpec.delegationTarget = true; |
| break; |
| } else if(!forwardLvarSpec.startsWith(commonLvarSpec)) { |
| break; |
| } |
| } |
| if(addNewHandler) { |
| // We need to insert a common prefix handler. Note handlers created with catchTarget == false |
| // will automatically have delegationTarget == true (because that's the only reason for their |
| // existence). |
| handlerSpecs.add(commonHandlerIndex, new OptimismExceptionHandlerSpec(commonLvarSpec, false)); |
| } |
| } |
| |
| firstArrayIndex = countSymbolsInLvarTypeDescriptor(commonLvarSpec); |
| lvarIndex = 0; |
| for(int j = 0; j < commonLvarSpec.length(); ++j) { |
| lvarIndex += CodeGeneratorLexicalContext.getTypeForSlotDescriptor(commonLvarSpec.charAt(j)).getSlots(); |
| } |
| firstLvarIndex = lvarIndex; |
| |
| // Create a delegation label if not already present |
| delegationLabel = delegationLabels.get(commonLvarSpec); |
| if(delegationLabel == null) { |
| // uo_pa == "unwarranted optimism, populate array" |
| delegationLabel = new Label("uo_pa_" + commonLvarSpec); |
| delegationLabels.put(commonLvarSpec, delegationLabel); |
| } |
| } |
| |
| // Load local variables handled by this handler on stack |
| int args = 0; |
| boolean symbolHadValue = false; |
| for(int typeIndex = commonLvarSpec == null ? 0 : commonLvarSpec.length(); typeIndex < lvarSpec.length(); ++typeIndex) { |
| final char typeDesc = lvarSpec.charAt(typeIndex); |
| final Type lvarType = CodeGeneratorLexicalContext.getTypeForSlotDescriptor(typeDesc); |
| if (!lvarType.isUnknown()) { |
| method.load(lvarType, lvarIndex); |
| symbolHadValue = true; |
| args++; |
| } else if(typeDesc == 'U' && !symbolHadValue) { |
| // Symbol boundary with undefined last value. Check if all previous values for this symbol were also |
| // undefined; if so, emit one explicit Undefined. This serves to ensure that we're emiting exactly |
| // one value for every symbol that uses local slots. While we could in theory ignore symbols that |
| // are undefined (in other words, dead) at the point where this exception was thrown, unfortunately |
| // we can't do it in practice. The reason for this is that currently our liveness analysis is |
| // coarse (it can determine whether a symbol has not been read with a particular type anywhere in |
| // the function being compiled, but that's it), and a symbol being promoted to Object due to a |
| // deoptimization will suddenly show up as "live for Object type", and previously dead U->O |
| // conversions on loop entries will suddenly become alive in the deoptimized method which will then |
| // expect a value for that slot in its continuation handler. If we had precise liveness analysis, we |
| // could go back to excluding known dead symbols from the payload of the RewriteException. |
| if(method.peekType() == Type.UNDEFINED) { |
| method.dup(); |
| } else { |
| method.loadUndefined(Type.OBJECT); |
| } |
| args++; |
| } |
| if(Character.isUpperCase(typeDesc)) { |
| // Reached symbol boundary; reset flag for the next symbol. |
| symbolHadValue = false; |
| } |
| lvarIndex += lvarType.getSlots(); |
| } |
| assert args > 0; |
| // Delegate actual storing into array to an array populator utility method. |
| //on the stack: |
| // object array to be populated |
| // start index |
| // a lot of types |
| method.dynamicArrayPopulatorCall(args + 1, firstArrayIndex); |
| if(delegationLabel != null) { |
| // We cascade to a prefix handler to fill out the rest of the local variables and throw the |
| // RewriteException. |
| assert !lastHandler; |
| assert commonLvarSpec != null; |
| // Must undefine the local variables that we have already processed for the sake of correct join on the |
| // delegate label |
| method.undefineLocalVariables(firstLvarIndex, true); |
| final OptimismExceptionHandlerSpec nextSpec = handlerSpecs.get(handlerIndex + 1); |
| // If the delegate immediately follows, and it's not a catch target (so it doesn't have array setup |
| // code) don't bother emitting a jump, as we'd just jump to the next instruction. |
| if(!nextSpec.lvarSpec.equals(commonLvarSpec) || nextSpec.catchTarget) { |
| method._goto(delegationLabel); |
| } |
| } else { |
| assert lastHandler; |
| // Nothing to delegate to, so this handler must create and throw the RewriteException. |
| // At this point we have the UnwarrantedOptimismException and the Object[] with local variables on |
| // stack. We need to create a RewriteException, push two references to it below the constructor |
| // arguments, invoke the constructor, and throw the exception. |
| loadConstant(getByteCodeSymbolNames(fn)); |
| if (isRestOf()) { |
| loadConstant(getContinuationEntryPoints()); |
| method.invoke(CREATE_REWRITE_EXCEPTION_REST_OF); |
| } else { |
| method.invoke(CREATE_REWRITE_EXCEPTION); |
| } |
| method.athrow(); |
| } |
| } |
| return true; |
| } |
| |
| private static String[] getByteCodeSymbolNames(final FunctionNode fn) { |
| // Only names of local variables on the function level are captured. This information is used to reduce |
| // deoptimizations, so as much as we can capture will help. We rely on the fact that function wide variables are |
| // all live all the time, so the array passed to rewrite exception contains one element for every slotted symbol |
| // here. |
| final List<String> names = new ArrayList<>(); |
| for (final Symbol symbol: fn.getBody().getSymbols()) { |
| if (symbol.hasSlot()) { |
| if (symbol.isScope()) { |
| // slot + scope can only be true for parameters |
| assert symbol.isParam(); |
| names.add(null); |
| } else { |
| names.add(symbol.getName()); |
| } |
| } |
| } |
| return names.toArray(new String[names.size()]); |
| } |
| |
| private static String commonPrefix(final String s1, final String s2) { |
| final int l1 = s1.length(); |
| final int l = Math.min(l1, s2.length()); |
| int lms = -1; // last matching symbol |
| for(int i = 0; i < l; ++i) { |
| final char c1 = s1.charAt(i); |
| if(c1 != s2.charAt(i)) { |
| return s1.substring(0, lms + 1); |
| } else if(Character.isUpperCase(c1)) { |
| lms = i; |
| } |
| } |
| return l == l1 ? s1 : s2; |
| } |
| |
| private static class OptimismExceptionHandlerSpec implements Comparable<OptimismExceptionHandlerSpec> { |
| private final String lvarSpec; |
| private final boolean catchTarget; |
| private boolean delegationTarget; |
| |
| OptimismExceptionHandlerSpec(final String lvarSpec, final boolean catchTarget) { |
| this.lvarSpec = lvarSpec; |
| this.catchTarget = catchTarget; |
| if(!catchTarget) { |
| delegationTarget = true; |
| } |
| } |
| |
| @Override |
| public int compareTo(final OptimismExceptionHandlerSpec o) { |
| return lvarSpec.compareTo(o.lvarSpec); |
| } |
| |
| @Override |
| public String toString() { |
| final StringBuilder b = new StringBuilder(64).append("[HandlerSpec ").append(lvarSpec); |
| if(catchTarget) { |
| b.append(", catchTarget"); |
| } |
| if(delegationTarget) { |
| b.append(", delegationTarget"); |
| } |
| return b.append("]").toString(); |
| } |
| } |
| |
| private static class ContinuationInfo { |
| private final Label handlerLabel; |
| private Label targetLabel; // Label for the target instruction. |
| int lvarCount; |
| // Indices of local variables that need to be loaded on the stack when this node completes |
| private int[] stackStoreSpec; |
| // Types of values loaded on the stack |
| private Type[] stackTypes; |
| // If non-null, this node should perform the requisite type conversion |
| private Type returnValueType; |
| // If we are in the middle of an object literal initialization, we need to update the map |
| private PropertyMap objectLiteralMap; |
| // Object literal stack depth for object literal - not necessarily top if property is a tree |
| private int objectLiteralStackDepth = -1; |
| // The line number at the continuation point |
| private int lineNumber; |
| // The active catch label, in case the continuation point is in a try/catch block |
| private Label catchLabel; |
| // The number of scopes that need to be popped before control is transferred to the catch label. |
| private int exceptionScopePops; |
| |
| ContinuationInfo() { |
| this.handlerLabel = new Label("continuation_handler"); |
| } |
| |
| Label getHandlerLabel() { |
| return handlerLabel; |
| } |
| |
| boolean hasTargetLabel() { |
| return targetLabel != null; |
| } |
| |
| Label getTargetLabel() { |
| return targetLabel; |
| } |
| |
| void setTargetLabel(final Label targetLabel) { |
| this.targetLabel = targetLabel; |
| } |
| |
| int[] getStackStoreSpec() { |
| return stackStoreSpec.clone(); |
| } |
| |
| void setStackStoreSpec(final int[] stackStoreSpec) { |
| this.stackStoreSpec = stackStoreSpec; |
| } |
| |
| Type[] getStackTypes() { |
| return stackTypes.clone(); |
| } |
| |
| void setStackTypes(final Type[] stackTypes) { |
| this.stackTypes = stackTypes; |
| } |
| |
| Type getReturnValueType() { |
| return returnValueType; |
| } |
| |
| void setReturnValueType(final Type returnValueType) { |
| this.returnValueType = returnValueType; |
| } |
| |
| int getObjectLiteralStackDepth() { |
| return objectLiteralStackDepth; |
| } |
| |
| void setObjectLiteralStackDepth(final int objectLiteralStackDepth) { |
| this.objectLiteralStackDepth = objectLiteralStackDepth; |
| } |
| |
| PropertyMap getObjectLiteralMap() { |
| return objectLiteralMap; |
| } |
| |
| void setObjectLiteralMap(final PropertyMap objectLiteralMap) { |
| this.objectLiteralMap = objectLiteralMap; |
| } |
| |
| @Override |
| public String toString() { |
| return "[localVariableTypes=" + targetLabel.getStack().getLocalVariableTypesCopy() + ", stackStoreSpec=" + |
| Arrays.toString(stackStoreSpec) + ", returnValueType=" + returnValueType + "]"; |
| } |
| } |
| |
| private ContinuationInfo getContinuationInfo() { |
| return continuationInfo; |
| } |
| |
| private void generateContinuationHandler() { |
| if (!isRestOf()) { |
| return; |
| } |
| |
| final ContinuationInfo ci = getContinuationInfo(); |
| method.label(ci.getHandlerLabel()); |
| |
| // There should never be an exception thrown from the continuation handler, but in case there is (meaning, |
| // Nashorn has a bug), then line number 0 will be an indication of where it came from (line numbers are Uint16). |
| method.lineNumber(0); |
| |
| final Label.Stack stack = ci.getTargetLabel().getStack(); |
| final List<Type> lvarTypes = stack.getLocalVariableTypesCopy(); |
| final BitSet symbolBoundary = stack.getSymbolBoundaryCopy(); |
| final int lvarCount = ci.lvarCount; |
| |
| final Type rewriteExceptionType = Type.typeFor(RewriteException.class); |
| // Store the RewriteException into an unused local variable slot. |
| method.load(rewriteExceptionType, 0); |
| method.storeTemp(rewriteExceptionType, lvarCount); |
| // Get local variable array |
| method.load(rewriteExceptionType, 0); |
| method.invoke(RewriteException.GET_BYTECODE_SLOTS); |
| // Store local variables. Note that deoptimization might introduce new value types for existing local variables, |
| // so we must use both liveLocals and symbolBoundary, as in some cases (when the continuation is inside of a try |
| // block) we need to store the incoming value into multiple slots. The optimism exception handlers will have |
| // exactly one array element for every symbol that uses bytecode storage. If in the originating method the value |
| // was undefined, there will be an explicit Undefined value in the array. |
| int arrayIndex = 0; |
| for(int lvarIndex = 0; lvarIndex < lvarCount;) { |
| final Type lvarType = lvarTypes.get(lvarIndex); |
| if(!lvarType.isUnknown()) { |
| method.dup(); |
| method.load(arrayIndex).arrayload(); |
| final Class<?> typeClass = lvarType.getTypeClass(); |
| // Deoptimization in array initializers can cause arrays to undergo component type widening |
| if(typeClass == long[].class) { |
| method.load(rewriteExceptionType, lvarCount); |
| method.invoke(RewriteException.TO_LONG_ARRAY); |
| } else if(typeClass == double[].class) { |
| method.load(rewriteExceptionType, lvarCount); |
| method.invoke(RewriteException.TO_DOUBLE_ARRAY); |
| } else if(typeClass == Object[].class) { |
| method.load(rewriteExceptionType, lvarCount); |
| method.invoke(RewriteException.TO_OBJECT_ARRAY); |
| } else { |
| if(!(typeClass.isPrimitive() || typeClass == Object.class)) { |
| // NOTE: this can only happen with dead stores. E.g. for the program "1; []; f();" in which the |
| // call to f() will deoptimize the call site, but it'll expect :return to have the type |
| // NativeArray. However, in the more optimal version, :return's only live type is int, therefore |
| // "{O}:return = []" is a dead store, and the variable will be sent into the continuation as |
| // Undefined, however NativeArray can't hold Undefined instance. |
| method.loadType(Type.getInternalName(typeClass)); |
| method.invoke(RewriteException.INSTANCE_OR_NULL); |
| } |
| method.convert(lvarType); |
| } |
| method.storeHidden(lvarType, lvarIndex, false); |
| } |
| final int nextLvarIndex = lvarIndex + lvarType.getSlots(); |
| if(symbolBoundary.get(nextLvarIndex - 1)) { |
| ++arrayIndex; |
| } |
| lvarIndex = nextLvarIndex; |
| } |
| if (AssertsEnabled.assertsEnabled()) { |
| method.load(arrayIndex); |
| method.invoke(RewriteException.ASSERT_ARRAY_LENGTH); |
| } else { |
| method.pop(); |
| } |
| |
| final int[] stackStoreSpec = ci.getStackStoreSpec(); |
| final Type[] stackTypes = ci.getStackTypes(); |
| final boolean isStackEmpty = stackStoreSpec.length == 0; |
| boolean replacedObjectLiteralMap = false; |
| if(!isStackEmpty) { |
| // Load arguments on the stack |
| final int objectLiteralStackDepth = ci.getObjectLiteralStackDepth(); |
| for(int i = 0; i < stackStoreSpec.length; ++i) { |
| final int slot = stackStoreSpec[i]; |
| method.load(lvarTypes.get(slot), slot); |
| method.convert(stackTypes[i]); |
| // stack: s0=object literal being initialized |
| // change map of s0 so that the property we are initializing when we failed |
| // is now ci.returnValueType |
| if (i == objectLiteralStackDepth) { |
| method.dup(); |
| assert ci.getObjectLiteralMap() != null; |
| assert ScriptObject.class.isAssignableFrom(method.peekType().getTypeClass()) : method.peekType().getTypeClass() + " is not a script object"; |
| loadConstant(ci.getObjectLiteralMap()); |
| method.invoke(ScriptObject.SET_MAP); |
| replacedObjectLiteralMap = true; |
| } |
| } |
| } |
| // Must have emitted the code for replacing the map of an object literal if we have a set object literal stack depth |
| assert ci.getObjectLiteralStackDepth() == -1 || replacedObjectLiteralMap; |
| // Load RewriteException back. |
| method.load(rewriteExceptionType, lvarCount); |
| // Get rid of the stored reference |
| method.loadNull(); |
| method.storeHidden(Type.OBJECT, lvarCount); |
| // Mark it dead |
| method.markDeadSlots(lvarCount, Type.OBJECT.getSlots()); |
| |
| // Load return value on the stack |
| method.invoke(RewriteException.GET_RETURN_VALUE); |
| |
| final Type returnValueType = ci.getReturnValueType(); |
| |
| // Set up an exception handler for primitive type conversion of return value if needed |
| boolean needsCatch = false; |
| final Label targetCatchLabel = ci.catchLabel; |
| Label _try = null; |
| if(returnValueType.isPrimitive()) { |
| // If the conversion throws an exception, we want to report the line number of the continuation point. |
| method.lineNumber(ci.lineNumber); |
| |
| if(targetCatchLabel != METHOD_BOUNDARY) { |
| _try = new Label(""); |
| method.label(_try); |
| needsCatch = true; |
| } |
| } |
| |
| // Convert return value |
| method.convert(returnValueType); |
| |
| final int scopePopCount = needsCatch ? ci.exceptionScopePops : 0; |
| |
| // Declare a try/catch for the conversion. If no scopes need to be popped until the target catch block, just |
| // jump into it. Otherwise, we'll need to create a scope-popping catch block below. |
| final Label catchLabel = scopePopCount > 0 ? new Label("") : targetCatchLabel; |
| if(needsCatch) { |
| final Label _end_try = new Label(""); |
| method.label(_end_try); |
| method._try(_try, _end_try, catchLabel); |
| } |
| |
| // Jump to continuation point |
| method._goto(ci.getTargetLabel()); |
| |
| // Make a scope-popping exception delegate if needed |
| if(catchLabel != targetCatchLabel) { |
| method.lineNumber(0); |
| assert scopePopCount > 0; |
| method._catch(catchLabel); |
| popScopes(scopePopCount); |
| method.uncheckedGoto(targetCatchLabel); |
| } |
| } |
| |
| /** |
| * Interface implemented by object creators that support splitting over multiple methods. |
| */ |
| interface SplitLiteralCreator { |
| /** |
| * Generate code to populate a range of the literal object. A reference to the object |
| * should be left on the stack when the method terminates. |
| * |
| * @param method the method emitter |
| * @param type the type of the literal object |
| * @param slot the local slot containing the literal object |
| * @param start the start index (inclusive) |
| * @param end the end index (exclusive) |
| */ |
| void populateRange(MethodEmitter method, Type type, int slot, int start, int end); |
| } |
| } |