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android / platform / external / jetbrains / jdk8u_nashorn / a5a7b25a2af093fc33691f5a9de884c6e6f64996 / . / src / jdk / nashorn / internal / codegen / MethodEmitter.java
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/*
* 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.internal.org.objectweb.asm.Opcodes.ATHROW;
import static jdk.internal.org.objectweb.asm.Opcodes.CHECKCAST;
import static jdk.internal.org.objectweb.asm.Opcodes.DUP2;
import static jdk.internal.org.objectweb.asm.Opcodes.GETFIELD;
import static jdk.internal.org.objectweb.asm.Opcodes.GETSTATIC;
import static jdk.internal.org.objectweb.asm.Opcodes.GOTO;
import static jdk.internal.org.objectweb.asm.Opcodes.H_INVOKESTATIC;
import static jdk.internal.org.objectweb.asm.Opcodes.IFEQ;
import static jdk.internal.org.objectweb.asm.Opcodes.IFGE;
import static jdk.internal.org.objectweb.asm.Opcodes.IFGT;
import static jdk.internal.org.objectweb.asm.Opcodes.IFLE;
import static jdk.internal.org.objectweb.asm.Opcodes.IFLT;
import static jdk.internal.org.objectweb.asm.Opcodes.IFNE;
import static jdk.internal.org.objectweb.asm.Opcodes.IFNONNULL;
import static jdk.internal.org.objectweb.asm.Opcodes.IFNULL;
import static jdk.internal.org.objectweb.asm.Opcodes.IF_ACMPEQ;
import static jdk.internal.org.objectweb.asm.Opcodes.IF_ACMPNE;
import static jdk.internal.org.objectweb.asm.Opcodes.IF_ICMPEQ;
import static jdk.internal.org.objectweb.asm.Opcodes.IF_ICMPGE;
import static jdk.internal.org.objectweb.asm.Opcodes.IF_ICMPGT;
import static jdk.internal.org.objectweb.asm.Opcodes.IF_ICMPLE;
import static jdk.internal.org.objectweb.asm.Opcodes.IF_ICMPLT;
import static jdk.internal.org.objectweb.asm.Opcodes.IF_ICMPNE;
import static jdk.internal.org.objectweb.asm.Opcodes.INSTANCEOF;
import static jdk.internal.org.objectweb.asm.Opcodes.INVOKEINTERFACE;
import static jdk.internal.org.objectweb.asm.Opcodes.INVOKESPECIAL;
import static jdk.internal.org.objectweb.asm.Opcodes.INVOKESTATIC;
import static jdk.internal.org.objectweb.asm.Opcodes.INVOKEVIRTUAL;
import static jdk.internal.org.objectweb.asm.Opcodes.NEW;
import static jdk.internal.org.objectweb.asm.Opcodes.PUTFIELD;
import static jdk.internal.org.objectweb.asm.Opcodes.PUTSTATIC;
import static jdk.internal.org.objectweb.asm.Opcodes.RETURN;
import static jdk.nashorn.internal.codegen.CompilerConstants.ARGUMENTS;
import static jdk.nashorn.internal.codegen.CompilerConstants.CONSTANTS;
import static jdk.nashorn.internal.codegen.CompilerConstants.SCOPE;
import static jdk.nashorn.internal.codegen.CompilerConstants.THIS;
import static jdk.nashorn.internal.codegen.CompilerConstants.THIS_DEBUGGER;
import static jdk.nashorn.internal.codegen.CompilerConstants.VARARGS;
import static jdk.nashorn.internal.codegen.CompilerConstants.className;
import static jdk.nashorn.internal.codegen.CompilerConstants.constructorNoLookup;
import static jdk.nashorn.internal.codegen.CompilerConstants.methodDescriptor;
import static jdk.nashorn.internal.codegen.CompilerConstants.staticField;
import static jdk.nashorn.internal.codegen.CompilerConstants.virtualCallNoLookup;
import static jdk.nashorn.internal.codegen.ObjectClassGenerator.PRIMITIVE_FIELD_TYPE;
import static jdk.nashorn.internal.runtime.linker.NashornCallSiteDescriptor.CALLSITE_OPTIMISTIC;
import static jdk.nashorn.internal.runtime.linker.NashornCallSiteDescriptor.CALLSITE_PROGRAM_POINT_SHIFT;
import java.io.PrintStream;
import java.lang.reflect.Array;
import java.util.Collection;
import java.util.EnumSet;
import java.util.IdentityHashMap;
import java.util.List;
import java.util.Map;
import jdk.internal.dynalink.support.NameCodec;
import jdk.internal.org.objectweb.asm.Handle;
import jdk.internal.org.objectweb.asm.MethodVisitor;
import jdk.nashorn.internal.codegen.ClassEmitter.Flag;
import jdk.nashorn.internal.codegen.CompilerConstants.Call;
import jdk.nashorn.internal.codegen.CompilerConstants.FieldAccess;
import jdk.nashorn.internal.codegen.types.ArrayType;
import jdk.nashorn.internal.codegen.types.BitwiseType;
import jdk.nashorn.internal.codegen.types.NumericType;
import jdk.nashorn.internal.codegen.types.Type;
import jdk.nashorn.internal.ir.FunctionNode;
import jdk.nashorn.internal.ir.IdentNode;
import jdk.nashorn.internal.ir.JoinPredecessor;
import jdk.nashorn.internal.ir.LiteralNode;
import jdk.nashorn.internal.ir.LocalVariableConversion;
import jdk.nashorn.internal.ir.Symbol;
import jdk.nashorn.internal.ir.TryNode;
import jdk.nashorn.internal.objects.Global;
import jdk.nashorn.internal.objects.NativeArray;
import jdk.nashorn.internal.runtime.ArgumentSetter;
import jdk.nashorn.internal.runtime.Context;
import jdk.nashorn.internal.runtime.Debug;
import jdk.nashorn.internal.runtime.JSType;
import jdk.nashorn.internal.runtime.RewriteException;
import jdk.nashorn.internal.runtime.Scope;
import jdk.nashorn.internal.runtime.ScriptObject;
import jdk.nashorn.internal.runtime.ScriptRuntime;
import jdk.nashorn.internal.runtime.UnwarrantedOptimismException;
import jdk.nashorn.internal.runtime.linker.Bootstrap;
import jdk.nashorn.internal.runtime.logging.DebugLogger;
import jdk.nashorn.internal.runtime.options.Options;
/**
* This is the main function responsible for emitting method code
* in a class. It maintains a type stack and keeps track of control
* flow to make sure that the registered instructions don't violate
* byte code verification.
*
* Running Nashorn with -ea will assert as soon as a type stack
* becomes corrupt, for easier debugging
*
* Running Nashorn with -Dnashorn.codegen.debug=true will print
* all generated bytecode and labels to stderr, for easier debugging,
* including bytecode stack contents
*/
public class MethodEmitter {
/** The ASM MethodVisitor we are plugged into */
private final MethodVisitor method;
/** Parent classEmitter representing the class of this method */
private final ClassEmitter classEmitter;
/** FunctionNode representing this method, or null if none exists */
protected FunctionNode functionNode;
/** Current type stack for current evaluation */
private Label.Stack stack;
private boolean preventUndefinedLoad;
/**
* Map of live local variable definitions.
*/
private final Map<Symbol, LocalVariableDef> localVariableDefs = new IdentityHashMap<>();
/** The context */
private final Context context;
/** Threshold in chars for when string constants should be split */
static final int LARGE_STRING_THRESHOLD = 32 * 1024;
/** Debug flag, should we dump all generated bytecode along with stacks? */
private final DebugLogger log;
private final boolean debug;
/** dump stack on a particular line, or -1 if disabled */
private static final int DEBUG_TRACE_LINE;
static {
final String tl = Options.getStringProperty("nashorn.codegen.debug.trace", "-1");
int line = -1;
try {
line = Integer.parseInt(tl);
} catch (final NumberFormatException e) {
//fallthru
}
DEBUG_TRACE_LINE = line;
}
/** Bootstrap for normal indy:s */
private static final Handle LINKERBOOTSTRAP = new Handle(H_INVOKESTATIC, Bootstrap.BOOTSTRAP.className(), Bootstrap.BOOTSTRAP.name(), Bootstrap.BOOTSTRAP.descriptor());
/** Bootstrap for array populators */
private static final Handle POPULATE_ARRAY_BOOTSTRAP = new Handle(H_INVOKESTATIC, RewriteException.BOOTSTRAP.className(), RewriteException.BOOTSTRAP.name(), RewriteException.BOOTSTRAP.descriptor());
/**
* Constructor - internal use from ClassEmitter only
* @see ClassEmitter#method
*
* @param classEmitter the class emitter weaving the class this method is in
* @param method a method visitor
*/
MethodEmitter(final ClassEmitter classEmitter, final MethodVisitor method) {
this(classEmitter, method, null);
}
/**
* Constructor - internal use from ClassEmitter only
* @see ClassEmitter#method
*
* @param classEmitter the class emitter weaving the class this method is in
* @param method a method visitor
* @param functionNode a function node representing this method
*/
MethodEmitter(final ClassEmitter classEmitter, final MethodVisitor method, final FunctionNode functionNode) {
this.context = classEmitter.getContext();
this.classEmitter = classEmitter;
this.method = method;
this.functionNode = functionNode;
this.stack = null;
this.log = context.getLogger(CodeGenerator.class);
this.debug = log.isEnabled();
}
/**
* Begin a method
*/
public void begin() {
classEmitter.beginMethod(this);
newStack();
method.visitCode();
}
/**
* End a method
*/
public void end() {
method.visitMaxs(0, 0);
method.visitEnd();
classEmitter.endMethod(this);
}
boolean isReachable() {
return stack != null;
}
private void doesNotContinueSequentially() {
stack = null;
}
private void newStack() {
stack = new Label.Stack();
}
@Override
public String toString() {
return "methodEmitter: " + (functionNode == null ? method : functionNode.getName()).toString() + ' ' + Debug.id(this);
}
/**
* Push a type to the existing stack
* @param type the type
*/
void pushType(final Type type) {
if (type != null) {
stack.push(type);
}
}
/**
* Pop a type from the existing stack
*
* @param expected expected type - will assert if wrong
*
* @return the type that was retrieved
*/
private Type popType(final Type expected) {
final Type type = popType();
assert type.isEquivalentTo(expected) : type + " is not compatible with " + expected;
return type;
}
/**
* Pop a type from the existing stack, no matter what it is.
*
* @return the type
*/
private Type popType() {
return stack.pop();
}
/**
* Pop a type from the existing stack, ensuring that it is numeric. Boolean type is popped as int type.
*
* @return the type
*/
private NumericType popNumeric() {
final Type type = popType();
if(type.isBoolean()) {
// Booleans are treated as int for purposes of arithmetic operations
return Type.INT;
}
assert type.isNumeric();
return (NumericType)type;
}
/**
* Pop a type from the existing stack, ensuring that it is an integer type
* (integer or long). Boolean type is popped as int type.
*
* @return the type
*/
private BitwiseType popBitwise() {
final Type type = popType();
if(type == Type.BOOLEAN) {
return Type.INT;
}
return (BitwiseType)type;
}
private BitwiseType popInteger() {
final Type type = popType();
if(type == Type.BOOLEAN) {
return Type.INT;
}
assert type == Type.INT;
return (BitwiseType)type;
}
/**
* Pop a type from the existing stack, ensuring that it is an array type,
* assert if not
*
* @return the type
*/
private ArrayType popArray() {
final Type type = popType();
assert type.isArray() : type;
return (ArrayType)type;
}
/**
* Peek a given number of slots from the top of the stack and return the
* type in that slot
*
* @param pos the number of positions from the top, 0 is the top element
*
* @return the type at position "pos" on the stack
*/
final Type peekType(final int pos) {
return stack.peek(pos);
}
/**
* Peek at the type at the top of the stack
*
* @return the type at the top of the stack
*/
final Type peekType() {
return stack.peek();
}
/**
* Generate code a for instantiating a new object and push the
* object type on the stack
*
* @param classDescriptor class descriptor for the object type
* @param type the type of the new object
*
* @return the method emitter
*/
MethodEmitter _new(final String classDescriptor, final Type type) {
debug("new", classDescriptor);
method.visitTypeInsn(NEW, classDescriptor);
pushType(type);
return this;
}
/**
* Generate code a for instantiating a new object and push the
* object type on the stack
*
* @param clazz class type to instatiate
*
* @return the method emitter
*/
MethodEmitter _new(final Class<?> clazz) {
return _new(className(clazz), Type.typeFor(clazz));
}
/**
* Generate code to call the empty constructor for a class
*
* @param clazz class type to instatiate
*
* @return the method emitter
*/
MethodEmitter newInstance(final Class<?> clazz) {
return invoke(constructorNoLookup(clazz));
}
/**
* Perform a dup, that is, duplicate the top element and
* push the duplicate down a given number of positions
* on the stack. This is totally type agnostic.
*
* @param depth the depth on which to put the copy
*
* @return the method emitter, or null if depth is illegal and
* has no instruction equivalent.
*/
MethodEmitter dup(final int depth) {
if (peekType().dup(method, depth) == null) {
return null;
}
debug("dup", depth);
switch (depth) {
case 0: {
final int l0 = stack.getTopLocalLoad();
pushType(peekType());
stack.markLocalLoad(l0);
break;
}
case 1: {
final int l0 = stack.getTopLocalLoad();
final Type p0 = popType();
final int l1 = stack.getTopLocalLoad();
final Type p1 = popType();
pushType(p0);
stack.markLocalLoad(l0);
pushType(p1);
stack.markLocalLoad(l1);
pushType(p0);
stack.markLocalLoad(l0);
break;
}
case 2: {
final int l0 = stack.getTopLocalLoad();
final Type p0 = popType();
final int l1 = stack.getTopLocalLoad();
final Type p1 = popType();
final int l2 = stack.getTopLocalLoad();
final Type p2 = popType();
pushType(p0);
stack.markLocalLoad(l0);
pushType(p2);
stack.markLocalLoad(l2);
pushType(p1);
stack.markLocalLoad(l1);
pushType(p0);
stack.markLocalLoad(l0);
break;
}
default:
assert false : "illegal dup depth = " + depth;
return null;
}
return this;
}
/**
* Perform a dup2, that is, duplicate the top element if it
* is a category 2 type, or two top elements if they are category
* 1 types, and push them on top of the stack
*
* @return the method emitter
*/
MethodEmitter dup2() {
debug("dup2");
if (peekType().isCategory2()) {
final int l0 = stack.getTopLocalLoad();
pushType(peekType());
stack.markLocalLoad(l0);
} else {
final int l0 = stack.getTopLocalLoad();
final Type p0 = popType();
final int l1 = stack.getTopLocalLoad();
final Type p1 = popType();
pushType(p0);
stack.markLocalLoad(l0);
pushType(p1);
stack.markLocalLoad(l1);
pushType(p0);
stack.markLocalLoad(l0);
pushType(p1);
stack.markLocalLoad(l1);
}
method.visitInsn(DUP2);
return this;
}
/**
* Duplicate the top element on the stack and push it
*
* @return the method emitter
*/
MethodEmitter dup() {
return dup(0);
}
/**
* Pop the top element of the stack and throw it away
*
* @return the method emitter
*/
MethodEmitter pop() {
debug("pop", peekType());
popType().pop(method);
return this;
}
/**
* Pop the top element of the stack if category 2 type, or the two
* top elements of the stack if category 1 types
*
* @return the method emitter
*/
MethodEmitter pop2() {
if (peekType().isCategory2()) {
popType();
} else {
get2n();
}
return this;
}
/**
* Swap the top two elements of the stack. This is totally
* type agnostic and works for all types
*
* @return the method emitter
*/
MethodEmitter swap() {
debug("swap");
final int l0 = stack.getTopLocalLoad();
final Type p0 = popType();
final int l1 = stack.getTopLocalLoad();
final Type p1 = popType();
p0.swap(method, p1);
pushType(p0);
stack.markLocalLoad(l0);
pushType(p1);
stack.markLocalLoad(l1);
return this;
}
void pack() {
final Type type = peekType();
if (type.isInteger()) {
convert(PRIMITIVE_FIELD_TYPE);
} else if (type.isLong()) {
//nop
} else if (type.isNumber()) {
invokestatic("java/lang/Double", "doubleToRawLongBits", "(D)J");
} else {
assert false : type + " cannot be packed!";
}
}
/**
* Initializes a bytecode method parameter
* @param symbol the symbol for the parameter
* @param type the type of the parameter
* @param start the label for the start of the method
*/
void initializeMethodParameter(final Symbol symbol, final Type type, final Label start) {
assert symbol.isBytecodeLocal();
localVariableDefs.put(symbol, new LocalVariableDef(start.getLabel(), type));
}
/**
* Create a new string builder, call the constructor and push the instance to the stack.
*
* @return the method emitter
*/
MethodEmitter newStringBuilder() {
return invoke(constructorNoLookup(StringBuilder.class)).dup();
}
/**
* Pop a string and a StringBuilder from the top of the stack and call the append
* function of the StringBuilder, appending the string. Pushes the StringBuilder to
* the stack when finished.
*
* @return the method emitter
*/
MethodEmitter stringBuilderAppend() {
convert(Type.STRING);
return invoke(virtualCallNoLookup(StringBuilder.class, "append", StringBuilder.class, String.class));
}
/**
* Pops two integer types from the stack, performs a bitwise and and pushes
* the result
*
* @return the method emitter
*/
MethodEmitter and() {
debug("and");
pushType(get2i().and(method));
return this;
}
/**
* Pops two integer types from the stack, performs a bitwise or and pushes
* the result
*
* @return the method emitter
*/
MethodEmitter or() {
debug("or");
pushType(get2i().or(method));
return this;
}
/**
* Pops two integer types from the stack, performs a bitwise xor and pushes
* the result
*
* @return the method emitter
*/
MethodEmitter xor() {
debug("xor");
pushType(get2i().xor(method));
return this;
}
/**
* Pops two integer types from the stack, performs a bitwise logic shift right and pushes
* the result. The shift count, the first element, must be INT.
*
* @return the method emitter
*/
MethodEmitter shr() {
debug("shr");
popInteger();
pushType(popBitwise().shr(method));
return this;
}
/**
* Pops two integer types from the stack, performs a bitwise shift left and and pushes
* the result. The shift count, the first element, must be INT.
*
* @return the method emitter
*/
MethodEmitter shl() {
debug("shl");
popInteger();
pushType(popBitwise().shl(method));
return this;
}
/**
* Pops two integer types from the stack, performs a bitwise arithmetic shift right and pushes
* the result. The shift count, the first element, must be INT.
*
* @return the method emitter
*/
MethodEmitter sar() {
debug("sar");
popInteger();
pushType(popBitwise().sar(method));
return this;
}
/**
* Pops a numeric type from the stack, negates it and pushes the result
*
* @return the method emitter
*/
MethodEmitter neg(final int programPoint) {
debug("neg");
pushType(popNumeric().neg(method, programPoint));
return this;
}
/**
* Add label for the start of a catch block and push the exception to the
* stack
*
* @param recovery label pointing to start of catch block
*/
void _catch(final Label recovery) {
// While in JVM a catch block can be reached through normal control flow, our code generator never does this,
// so we might as well presume there's no stack on entry.
assert stack == null;
recovery.onCatch();
label(recovery);
beginCatchBlock();
}
/**
* Add any number of labels for the start of a catch block and push the exception to the
* stack
*
* @param recoveries labels pointing to start of catch block
*/
void _catch(final Collection<Label> recoveries) {
assert stack == null;
for(final Label l: recoveries) {
label(l);
}
beginCatchBlock();
}
private void beginCatchBlock() {
// It can happen that the catch label wasn't marked as reachable. They are marked as reachable if there's an
// assignment in the try block, but it's possible that there was none.
if(!isReachable()) {
newStack();
}
pushType(Type.typeFor(Throwable.class));
}
/**
* Start a try/catch block.
*
* @param entry start label for try
* @param exit end label for try
* @param recovery start label for catch
* @param typeDescriptor type descriptor for exception
* @param isOptimismHandler true if this is a hander for {@code UnwarrantedOptimismException}. Normally joining on a
* catch handler kills temporary variables, but optimism handlers are an exception, as they need to capture
* temporaries as well, so they must remain live.
*/
private void _try(final Label entry, final Label exit, final Label recovery, final String typeDescriptor, final boolean isOptimismHandler) {
recovery.joinFromTry(entry.getStack(), isOptimismHandler);
method.visitTryCatchBlock(entry.getLabel(), exit.getLabel(), recovery.getLabel(), typeDescriptor);
}
/**
* Start a try/catch block.
*
* @param entry start label for try
* @param exit end label for try
* @param recovery start label for catch
* @param clazz exception class
*/
void _try(final Label entry, final Label exit, final Label recovery, final Class<?> clazz) {
_try(entry, exit, recovery, CompilerConstants.className(clazz), clazz == UnwarrantedOptimismException.class);
}
/**
* Start a try/catch block. The catch is "Throwable" - i.e. catch-all
*
* @param entry start label for try
* @param exit end label for try
* @param recovery start label for catch
*/
void _try(final Label entry, final Label exit, final Label recovery) {
_try(entry, exit, recovery, (String)null, false);
}
void markLabelAsOptimisticCatchHandler(final Label label, final int liveLocalCount) {
label.markAsOptimisticCatchHandler(stack, liveLocalCount);
}
/**
* Load the constants array
* @return this method emitter
*/
MethodEmitter loadConstants() {
getStatic(classEmitter.getUnitClassName(), CONSTANTS.symbolName(), CONSTANTS.descriptor());
assert peekType().isArray() : peekType();
return this;
}
/**
* Push the undefined value for the given type, i.e.
* UNDEFINED or UNDEFINEDNUMBER. Currently we have no way of
* representing UNDEFINED for INTs and LONGs, so they are not
* allowed to be local variables (yet)
*
* @param type the type for which to push UNDEFINED
* @return the method emitter
*/
MethodEmitter loadUndefined(final Type type) {
debug("load undefined ", type);
pushType(type.loadUndefined(method));
return this;
}
MethodEmitter loadForcedInitializer(final Type type) {
debug("load forced initializer ", type);
pushType(type.loadForcedInitializer(method));
return this;
}
/**
* Push the empty value for the given type, i.e. EMPTY.
*
* @param type the type
* @return the method emitter
*/
MethodEmitter loadEmpty(final Type type) {
debug("load empty ", type);
pushType(type.loadEmpty(method));
return this;
}
/**
* Push null to stack
*
* @return the method emitter
*/
MethodEmitter loadNull() {
debug("aconst_null");
pushType(Type.OBJECT.ldc(method, null));
return this;
}
/**
* Push a handle representing this class top stack
*
* @param className name of the class
*
* @return the method emitter
*/
MethodEmitter loadType(final String className) {
debug("load type", className);
method.visitLdcInsn(jdk.internal.org.objectweb.asm.Type.getObjectType(className));
pushType(Type.OBJECT);
return this;
}
/**
* Push a boolean constant to the stack.
*
* @param b value of boolean
*
* @return the method emitter
*/
MethodEmitter load(final boolean b) {
debug("load boolean", b);
pushType(Type.BOOLEAN.ldc(method, b));
return this;
}
/**
* Push an int constant to the stack
*
* @param i value of the int
*
* @return the method emitter
*/
MethodEmitter load(final int i) {
debug("load int", i);
pushType(Type.INT.ldc(method, i));
return this;
}
/**
* Push a double constant to the stack
*
* @param d value of the double
*
* @return the method emitter
*/
MethodEmitter load(final double d) {
debug("load double", d);
pushType(Type.NUMBER.ldc(method, d));
return this;
}
/**
* Push an long constant to the stack
*
* @param l value of the long
*
* @return the method emitter
*/
MethodEmitter load(final long l) {
debug("load long", l);
pushType(Type.LONG.ldc(method, l));
return this;
}
/**
* Fetch the length of an array.
* @return Array length.
*/
MethodEmitter arraylength() {
debug("arraylength");
popType(Type.OBJECT);
pushType(Type.OBJECT_ARRAY.arraylength(method));
return this;
}
/**
* Push a String constant to the stack
*
* @param s value of the String
*
* @return the method emitter
*/
MethodEmitter load(final String s) {
debug("load string", s);
if (s == null) {
loadNull();
return this;
}
//NASHORN-142 - split too large string
final int length = s.length();
if (length > LARGE_STRING_THRESHOLD) {
_new(StringBuilder.class);
dup();
load(length);
invoke(constructorNoLookup(StringBuilder.class, int.class));
for (int n = 0; n < length; n += LARGE_STRING_THRESHOLD) {
final String part = s.substring(n, Math.min(n + LARGE_STRING_THRESHOLD, length));
load(part);
stringBuilderAppend();
}
invoke(virtualCallNoLookup(StringBuilder.class, "toString", String.class));
return this;
}
pushType(Type.OBJECT.ldc(method, s));
return this;
}
/**
* Pushes the value of an identifier to the stack. If the identifier does not represent a local variable or a
* parameter, this will be a no-op.
*
* @param ident the identifier for the variable being loaded.
*
* @return the method emitter
*/
MethodEmitter load(final IdentNode ident) {
return load(ident.getSymbol(), ident.getType());
}
/**
* Pushes the value of the symbol to the stack with the specified type. No type conversion is being performed, and
* the type is only being used if the symbol addresses a local variable slot. The value of the symbol is loaded if
* it addresses a local variable slot, or it is a parameter (in which case it can also be loaded from a vararg array
* or the arguments object). If it is neither, the operation is a no-op.
*
* @param symbol the symbol addressing the value being loaded
* @param type the presumed type of the value when it is loaded from a local variable slot
* @return the method emitter
*/
MethodEmitter load(final Symbol symbol, final Type type) {
assert symbol != null;
if (symbol.hasSlot()) {
final int slot = symbol.getSlot(type);
debug("load symbol", symbol.getName(), " slot=", slot, "type=", type);
load(type, slot);
// _try(new Label("dummy"), new Label("dummy2"), recovery);
// method.visitTryCatchBlock(new Label(), arg1, arg2, arg3);
} else if (symbol.isParam()) {
assert functionNode.isVarArg() : "Non-vararg functions have slotted parameters";
final int index = symbol.getFieldIndex();
if (functionNode.needsArguments()) {
// ScriptObject.getArgument(int) on arguments
debug("load symbol", symbol.getName(), " arguments index=", index);
loadCompilerConstant(ARGUMENTS);
load(index);
ScriptObject.GET_ARGUMENT.invoke(this);
} else {
// array load from __varargs__
debug("load symbol", symbol.getName(), " array index=", index);
loadCompilerConstant(VARARGS);
load(symbol.getFieldIndex());
arrayload();
}
}
return this;
}
/**
* Push a local variable to the stack, given an explicit bytecode slot.
* This is used e.g. for stub generation where we know where items like
* "this" and "scope" reside.
*
* @param type the type of the variable
* @param slot the slot the variable is in
*
* @return the method emitter
*/
MethodEmitter load(final Type type, final int slot) {
debug("explicit load", type, slot);
final Type loadType = type.load(method, slot);
assert loadType != null;
pushType(loadType == Type.OBJECT && isThisSlot(slot) ? Type.THIS : loadType);
assert !preventUndefinedLoad || (slot < stack.localVariableTypes.size() && stack.localVariableTypes.get(slot) != Type.UNKNOWN)
: "Attempted load of uninitialized slot " + slot + " (as type " + type + ")";
stack.markLocalLoad(slot);
return this;
}
private boolean isThisSlot(final int slot) {
if (functionNode == null) {
return slot == CompilerConstants.JAVA_THIS.slot();
}
final int thisSlot = getCompilerConstantSymbol(THIS).getSlot(Type.OBJECT);
assert !functionNode.needsCallee() || thisSlot == 1; // needsCallee -> thisSlot == 1
assert functionNode.needsCallee() || thisSlot == 0; // !needsCallee -> thisSlot == 0
return slot == thisSlot;
}
/**
* Push a method handle to the stack
*
* @param className class name
* @param methodName method name
* @param descName descriptor
* @param flags flags that describe this handle, e.g. invokespecial new, or invoke virtual
*
* @return the method emitter
*/
MethodEmitter loadHandle(final String className, final String methodName, final String descName, final EnumSet<Flag> flags) {
debug("load handle ");
pushType(Type.OBJECT.ldc(method, new Handle(Flag.getValue(flags), className, methodName, descName)));
return this;
}
private Symbol getCompilerConstantSymbol(final CompilerConstants cc) {
return functionNode.getBody().getExistingSymbol(cc.symbolName());
}
/**
* True if this method has a slot allocated for the scope variable (meaning, something in the method actually needs
* the scope).
* @return if this method has a slot allocated for the scope variable.
*/
boolean hasScope() {
return getCompilerConstantSymbol(SCOPE).hasSlot();
}
MethodEmitter loadCompilerConstant(final CompilerConstants cc) {
return loadCompilerConstant(cc, null);
}
MethodEmitter loadCompilerConstant(final CompilerConstants cc, final Type type) {
if (cc == SCOPE && peekType() == Type.SCOPE) {
dup();
return this;
}
return load(getCompilerConstantSymbol(cc), type != null ? type : getCompilerConstantType(cc));
}
MethodEmitter loadScope() {
return loadCompilerConstant(SCOPE).checkcast(Scope.class);
}
MethodEmitter setSplitState(final int state) {
return loadScope().load(state).invoke(Scope.SET_SPLIT_STATE);
}
void storeCompilerConstant(final CompilerConstants cc) {
storeCompilerConstant(cc, null);
}
void storeCompilerConstant(final CompilerConstants cc, final Type type) {
final Symbol symbol = getCompilerConstantSymbol(cc);
if(!symbol.hasSlot()) {
return;
}
debug("store compiler constant ", symbol);
store(symbol, type != null ? type : getCompilerConstantType(cc));
}
private static Type getCompilerConstantType(final CompilerConstants cc) {
final Class<?> constantType = cc.type();
assert constantType != null;
return Type.typeFor(constantType);
}
/**
* Load an element from an array, determining type automatically
* @return the method emitter
*/
MethodEmitter arrayload() {
debug("Xaload");
popType(Type.INT);
pushType(popArray().aload(method));
return this;
}
/**
* Pop a value, an index and an array from the stack and store
* the value at the given index in the array.
*/
void arraystore() {
debug("Xastore");
final Type value = popType();
final Type index = popType(Type.INT);
assert index.isInteger() : "array index is not integer, but " + index;
final ArrayType array = popArray();
assert value.isEquivalentTo(array.getElementType()) : "Storing "+value+" into "+array;
assert array.isObject();
array.astore(method);
}
/**
* Pop a value from the stack and store it in a local variable represented
* by the given identifier. If the symbol has no slot, this is a NOP
*
* @param ident identifier to store stack to
*/
void store(final IdentNode ident) {
final Type type = ident.getType();
final Symbol symbol = ident.getSymbol();
if(type == Type.UNDEFINED) {
assert peekType() == Type.UNDEFINED;
store(symbol, Type.OBJECT);
} else {
store(symbol, type);
}
}
/**
* Represents a definition of a local variable with a type. Used for local variable table building.
*/
private static class LocalVariableDef {
// The start label from where this definition lives.
private final jdk.internal.org.objectweb.asm.Label label;
// The currently live type of the local variable.
private final Type type;
LocalVariableDef(final jdk.internal.org.objectweb.asm.Label label, final Type type) {
this.label = label;
this.type = type;
}
}
void closeLocalVariable(final Symbol symbol, final Label label) {
final LocalVariableDef def = localVariableDefs.get(symbol);
if(def != null) {
endLocalValueDef(symbol, def, label.getLabel());
}
if(isReachable()) {
markDeadLocalVariable(symbol);
}
}
void markDeadLocalVariable(final Symbol symbol) {
if(!symbol.isDead()) {
markDeadSlots(symbol.getFirstSlot(), symbol.slotCount());
}
}
void markDeadSlots(final int firstSlot, final int slotCount) {
stack.markDeadLocalVariables(firstSlot, slotCount);
}
private void endLocalValueDef(final Symbol symbol, final LocalVariableDef def, final jdk.internal.org.objectweb.asm.Label label) {
String name = symbol.getName();
if (name.equals(THIS.symbolName())) {
name = THIS_DEBUGGER.symbolName();
}
method.visitLocalVariable(name, def.type.getDescriptor(), null, def.label, label, symbol.getSlot(def.type));
}
void store(final Symbol symbol, final Type type) {
store(symbol, type, true);
}
/**
* Pop a value from the stack and store it in a variable denoted by the given symbol. The variable should be either
* a local variable, or a function parameter (and not a scoped variable). For local variables, this method will also
* do the bookkeeping of the local variable table as well as mark values in all alternative slots for the symbol as
* dead. In this regard it differs from {@link #storeHidden(Type, int)}.
*
* @param symbol the symbol to store into.
* @param type the type to store
* @param onlySymbolLiveValue if true, this is the sole live value for the symbol. If false, currently live values should
* be kept live.
*/
void store(final Symbol symbol, final Type type, final boolean onlySymbolLiveValue) {
assert symbol != null : "No symbol to store";
if (symbol.hasSlot()) {
final boolean isLiveType = symbol.hasSlotFor(type);
final LocalVariableDef existingDef = localVariableDefs.get(symbol);
if(existingDef == null || existingDef.type != type) {
final jdk.internal.org.objectweb.asm.Label here = new jdk.internal.org.objectweb.asm.Label();
if(isLiveType) {
final LocalVariableDef newDef = new LocalVariableDef(here, type);
localVariableDefs.put(symbol, newDef);
}
method.visitLabel(here);
if(existingDef != null) {
endLocalValueDef(symbol, existingDef, here);
}
}
if(isLiveType) {
final int slot = symbol.getSlot(type);
debug("store symbol", symbol.getName(), " type=", type, " slot=", slot);
storeHidden(type, slot, onlySymbolLiveValue);
} else {
if(onlySymbolLiveValue) {
markDeadLocalVariable(symbol);
}
debug("dead store symbol ", symbol.getName(), " type=", type);
pop();
}
} else if (symbol.isParam()) {
assert !symbol.isScope();
assert functionNode.isVarArg() : "Non-vararg functions have slotted parameters";
final int index = symbol.getFieldIndex();
if (functionNode.needsArguments()) {
convert(Type.OBJECT);
debug("store symbol", symbol.getName(), " arguments index=", index);
loadCompilerConstant(ARGUMENTS);
load(index);
ArgumentSetter.SET_ARGUMENT.invoke(this);
} else {
convert(Type.OBJECT);
// varargs without arguments object - just do array store to __varargs__
debug("store symbol", symbol.getName(), " array index=", index);
loadCompilerConstant(VARARGS);
load(index);
ArgumentSetter.SET_ARRAY_ELEMENT.invoke(this);
}
} else {
debug("dead store symbol ", symbol.getName(), " type=", type);
pop();
}
}
/**
* Pop a value from the stack and store it in a local variable slot. Note that in contrast with
* {@link #store(Symbol, Type)}, this method does not adjust the local variable table, nor marks slots for
* alternative value types for the symbol as being dead. For that reason, this method is usually not called
* directly. Notable exceptions are temporary internal locals (e.g. quick store, last-catch-condition, etc.) that
* are not desired to show up in the local variable table.
*
* @param type the type to pop
* @param slot the slot
*/
void storeHidden(final Type type, final int slot) {
storeHidden(type, slot, true);
}
void storeHidden(final Type type, final int slot, final boolean onlyLiveSymbolValue) {
explicitStore(type, slot);
stack.onLocalStore(type, slot, onlyLiveSymbolValue);
}
void storeTemp(final Type type, final int slot) {
explicitStore(type, slot);
defineTemporaryLocalVariable(slot, slot + type.getSlots());
onLocalStore(type, slot);
}
void onLocalStore(final Type type, final int slot) {
stack.onLocalStore(type, slot, true);
}
private void explicitStore(final Type type, final int slot) {
assert slot != -1;
debug("explicit store", type, slot);
popType(type);
type.store(method, slot);
}
/**
* Marks a range of slots as belonging to a defined local variable. The slots will start out with no live value
* in them.
* @param fromSlot first slot, inclusive.
* @param toSlot last slot, exclusive.
*/
void defineBlockLocalVariable(final int fromSlot, final int toSlot) {
stack.defineBlockLocalVariable(fromSlot, toSlot);
}
/**
* Marks a range of slots as belonging to a defined temporary local variable. The slots will start out with no
* live value in them.
* @param fromSlot first slot, inclusive.
* @param toSlot last slot, exclusive.
*/
void defineTemporaryLocalVariable(final int fromSlot, final int toSlot) {
stack.defineTemporaryLocalVariable(fromSlot, toSlot);
}
/**
* Defines a new temporary local variable and returns its allocated index.
* @param width the required width (in slots) for the new variable.
* @return the bytecode slot index where the newly allocated local begins.
*/
int defineTemporaryLocalVariable(final int width) {
return stack.defineTemporaryLocalVariable(width);
}
void undefineLocalVariables(final int fromSlot, final boolean canTruncateSymbol) {
if(isReachable()) {
stack.undefineLocalVariables(fromSlot, canTruncateSymbol);
}
}
List<Type> getLocalVariableTypes() {
return stack.localVariableTypes;
}
List<Type> getWidestLiveLocals(final List<Type> localTypes) {
return stack.getWidestLiveLocals(localTypes);
}
String markSymbolBoundariesInLvarTypesDescriptor(final String lvarDescriptor) {
return stack.markSymbolBoundariesInLvarTypesDescriptor(lvarDescriptor);
}
/**
* Increment/Decrement a local integer by the given value.
*
* @param slot the int slot
* @param increment the amount to increment
*/
void iinc(final int slot, final int increment) {
debug("iinc");
method.visitIincInsn(slot, increment);
}
/**
* Pop an exception object from the stack and generate code
* for throwing it
*/
public void athrow() {
debug("athrow");
final Type receiver = popType(Type.OBJECT);
assert Throwable.class.isAssignableFrom(receiver.getTypeClass()) : receiver.getTypeClass();
method.visitInsn(ATHROW);
doesNotContinueSequentially();
}
/**
* Pop an object from the stack and perform an instanceof
* operation, given a classDescriptor to compare it to.
* Push the boolean result 1/0 as an int to the stack
*
* @param classDescriptor descriptor of the class to type check against
*
* @return the method emitter
*/
MethodEmitter _instanceof(final String classDescriptor) {
debug("instanceof", classDescriptor);
popType(Type.OBJECT);
method.visitTypeInsn(INSTANCEOF, classDescriptor);
pushType(Type.INT);
return this;
}
/**
* Pop an object from the stack and perform an instanceof
* operation, given a classDescriptor to compare it to.
* Push the boolean result 1/0 as an int to the stack
*
* @param clazz the type to check instanceof against
*
* @return the method emitter
*/
MethodEmitter _instanceof(final Class<?> clazz) {
return _instanceof(CompilerConstants.className(clazz));
}
/**
* Perform a checkcast operation on the object at the top of the
* stack.
*
* @param classDescriptor descriptor of the class to type check against
*
* @return the method emitter
*/
MethodEmitter checkcast(final String classDescriptor) {
debug("checkcast", classDescriptor);
assert peekType().isObject();
method.visitTypeInsn(CHECKCAST, classDescriptor);
return this;
}
/**
* Perform a checkcast operation on the object at the top of the
* stack.
*
* @param clazz class to checkcast against
*
* @return the method emitter
*/
MethodEmitter checkcast(final Class<?> clazz) {
return checkcast(CompilerConstants.className(clazz));
}
/**
* Instantiate a new array given a length that is popped
* from the stack and the array type
*
* @param arrayType the type of the array
*
* @return the method emitter
*/
MethodEmitter newarray(final ArrayType arrayType) {
debug("newarray ", "arrayType=", arrayType);
popType(Type.INT); //LENGTH
pushType(arrayType.newarray(method));
return this;
}
/**
* Instantiate a multidimensional array with a given number of dimensions.
* On the stack are dim lengths of the sub arrays.
*
* @param arrayType type of the array
* @param dims number of dimensions
*
* @return the method emitter
*/
MethodEmitter multinewarray(final ArrayType arrayType, final int dims) {
debug("multianewarray ", arrayType, dims);
for (int i = 0; i < dims; i++) {
popType(Type.INT); //LENGTH
}
pushType(arrayType.newarray(method, dims));
return this;
}
/**
* Helper function to pop and type check the appropriate arguments
* from the stack given a method signature
*
* @param signature method signature
*
* @return return type of method
*/
private Type fixParamStack(final String signature) {
final Type[] params = Type.getMethodArguments(signature);
for (int i = params.length - 1; i >= 0; i--) {
popType(params[i]);
}
final Type returnType = Type.getMethodReturnType(signature);
return returnType;
}
/**
* Generate an invocation to a Call structure
* @see CompilerConstants
*
* @param call the call object
*
* @return the method emitter
*/
MethodEmitter invoke(final Call call) {
return call.invoke(this);
}
private MethodEmitter invoke(final int opcode, final String className, final String methodName, final String methodDescriptor, final boolean hasReceiver) {
final Type returnType = fixParamStack(methodDescriptor);
if (hasReceiver) {
popType(Type.OBJECT);
}
method.visitMethodInsn(opcode, className, methodName, methodDescriptor, opcode == INVOKEINTERFACE);
if (returnType != null) {
pushType(returnType);
}
return this;
}
/**
* Pop receiver from stack, perform an invoke special
*
* @param className class name
* @param methodName method name
* @param methodDescriptor descriptor
*
* @return the method emitter
*/
MethodEmitter invokespecial(final String className, final String methodName, final String methodDescriptor) {
debug("invokespecial", className, ".", methodName, methodDescriptor);
return invoke(INVOKESPECIAL, className, methodName, methodDescriptor, true);
}
/**
* Pop receiver from stack, perform an invoke virtual, push return value if any
*
* @param className class name
* @param methodName method name
* @param methodDescriptor descriptor
*
* @return the method emitter
*/
MethodEmitter invokevirtual(final String className, final String methodName, final String methodDescriptor) {
debug("invokevirtual", className, ".", methodName, methodDescriptor, " ", stack);
return invoke(INVOKEVIRTUAL, className, methodName, methodDescriptor, true);
}
/**
* Perform an invoke static and push the return value if any
*
* @param className class name
* @param methodName method name
* @param methodDescriptor descriptor
*
* @return the method emitter
*/
MethodEmitter invokestatic(final String className, final String methodName, final String methodDescriptor) {
debug("invokestatic", className, ".", methodName, methodDescriptor);
invoke(INVOKESTATIC, className, methodName, methodDescriptor, false);
return this;
}
/**
* Perform an invoke static and replace the return type if we know better, e.g. Global.allocate
* that allocates an array should return an ObjectArray type as a NativeArray counts as that
*
* @param className class name
* @param methodName method name
* @param methodDescriptor descriptor
* @param returnType return type override
*
* @return the method emitter
*/
MethodEmitter invokestatic(final String className, final String methodName, final String methodDescriptor, final Type returnType) {
invokestatic(className, methodName, methodDescriptor);
popType();
pushType(returnType);
return this;
}
/**
* Pop receiver from stack, perform an invoke interface and push return value if any
*
* @param className class name
* @param methodName method name
* @param methodDescriptor descriptor
*
* @return the method emitter
*/
MethodEmitter invokeinterface(final String className, final String methodName, final String methodDescriptor) {
debug("invokeinterface", className, ".", methodName, methodDescriptor);
return invoke(INVOKEINTERFACE, className, methodName, methodDescriptor, true);
}
static jdk.internal.org.objectweb.asm.Label[] getLabels(final Label... table) {
final jdk.internal.org.objectweb.asm.Label[] internalLabels = new jdk.internal.org.objectweb.asm.Label[table.length];
for (int i = 0; i < table.length; i++) {
internalLabels[i] = table[i].getLabel();
}
return internalLabels;
}
/**
* Generate a lookup switch, popping the switch value from the stack
*
* @param defaultLabel default label
* @param values case values for the table
* @param table default label
*/
void lookupswitch(final Label defaultLabel, final int[] values, final Label... table) {//Collection<Label> table) {
debug("lookupswitch", peekType());
adjustStackForSwitch(defaultLabel, table);
method.visitLookupSwitchInsn(defaultLabel.getLabel(), values, getLabels(table));
doesNotContinueSequentially();
}
/**
* Generate a table switch
* @param lo low value
* @param hi high value
* @param defaultLabel default label
* @param table label table
*/
void tableswitch(final int lo, final int hi, final Label defaultLabel, final Label... table) {
debug("tableswitch", peekType());
adjustStackForSwitch(defaultLabel, table);
method.visitTableSwitchInsn(lo, hi, defaultLabel.getLabel(), getLabels(table));
doesNotContinueSequentially();
}
private void adjustStackForSwitch(final Label defaultLabel, final Label... table) {
popType(Type.INT);
joinTo(defaultLabel);
for(final Label label: table) {
joinTo(label);
}
}
/**
* Abstraction for performing a conditional jump of any type
*
* @see Condition
*
* @param cond the condition to test
* @param trueLabel the destination label is condition is true
*/
void conditionalJump(final Condition cond, final Label trueLabel) {
conditionalJump(cond, cond != Condition.GT && cond != Condition.GE, trueLabel);
}
/**
* Abstraction for performing a conditional jump of any type,
* including a dcmpg/dcmpl semantic for doubles.
*
* @param cond the condition to test
* @param isCmpG is this a dcmpg for numbers, false if it's a dcmpl
* @param trueLabel the destination label if condition is true
*/
void conditionalJump(final Condition cond, final boolean isCmpG, final Label trueLabel) {
if (peekType().isCategory2()) {
debug("[ld]cmp isCmpG=", isCmpG);
pushType(get2n().cmp(method, isCmpG));
jump(Condition.toUnary(cond), trueLabel, 1);
} else {
debug("if", cond);
jump(Condition.toBinary(cond, peekType().isObject()), trueLabel, 2);
}
}
/**
* Perform a non void return, popping the type from the stack
*
* @param type the type for the return
*/
void _return(final Type type) {
debug("return", type);
assert stack.size() == 1 : "Only return value on stack allowed at return point - depth=" + stack.size() + " stack = " + stack;
final Type stackType = peekType();
if (!Type.areEquivalent(type, stackType)) {
convert(type);
}
popType(type)._return(method);
doesNotContinueSequentially();
}
/**
* Perform a return using the stack top value as the guide for the type
*/
void _return() {
_return(peekType());
}
/**
* Perform a void return.
*/
void returnVoid() {
debug("return [void]");
assert stack.isEmpty() : stack;
method.visitInsn(RETURN);
doesNotContinueSequentially();
}
/**
* Perform a comparison of two number types that are popped from the stack
*
* @param isCmpG is this a dcmpg semantic, false if it's a dcmpl semantic
*
* @return the method emitter
*/
MethodEmitter cmp(final boolean isCmpG) {
pushType(get2n().cmp(method, isCmpG));
return this;
}
/**
* Helper function for jumps, conditional or not
* @param opcode opcode for jump
* @param label destination
* @param n elements on stack to compare, 0-2
*/
private void jump(final int opcode, final Label label, final int n) {
for (int i = 0; i < n; i++) {
assert peekType().isInteger() || peekType().isBoolean() || peekType().isObject() : "expecting integer type or object for jump, but found " + peekType();
popType();
}
joinTo(label);
method.visitJumpInsn(opcode, label.getLabel());
}
/**
* Generate an if_acmpeq
*
* @param label label to true case
*/
void if_acmpeq(final Label label) {
debug("if_acmpeq", label);
jump(IF_ACMPEQ, label, 2);
}
/**
* Generate an if_acmpne
*
* @param label label to true case
*/
void if_acmpne(final Label label) {
debug("if_acmpne", label);
jump(IF_ACMPNE, label, 2);
}
/**
* Generate an ifnull
*
* @param label label to true case
*/
void ifnull(final Label label) {
debug("ifnull", label);
jump(IFNULL, label, 1);
}
/**
* Generate an ifnonnull
*
* @param label label to true case
*/
void ifnonnull(final Label label) {
debug("ifnonnull", label);
jump(IFNONNULL, label, 1);
}
/**
* Generate an ifeq
*
* @param label label to true case
*/
void ifeq(final Label label) {
debug("ifeq ", label);
jump(IFEQ, label, 1);
}
/**
* Generate an if_icmpeq
*
* @param label label to true case
*/
void if_icmpeq(final Label label) {
debug("if_icmpeq", label);
jump(IF_ICMPEQ, label, 2);
}
/**
* Generate an if_ne
*
* @param label label to true case
*/
void ifne(final Label label) {
debug("ifne", label);
jump(IFNE, label, 1);
}
/**
* Generate an if_icmpne
*
* @param label label to true case
*/
void if_icmpne(final Label label) {
debug("if_icmpne", label);
jump(IF_ICMPNE, label, 2);
}
/**
* Generate an iflt
*
* @param label label to true case
*/
void iflt(final Label label) {
debug("iflt", label);
jump(IFLT, label, 1);
}
/**
* Generate an if_icmplt
*
* @param label label to true case
*/
void if_icmplt(final Label label) {
debug("if_icmplt", label);
jump(IF_ICMPLT, label, 2);
}
/**
* Generate an ifle
*
* @param label label to true case
*/
void ifle(final Label label) {
debug("ifle", label);
jump(IFLE, label, 1);
}
/**
* Generate an if_icmple
*
* @param label label to true case
*/
void if_icmple(final Label label) {
debug("if_icmple", label);
jump(IF_ICMPLE, label, 2);
}
/**
* Generate an ifgt
*
* @param label label to true case
*/
void ifgt(final Label label) {
debug("ifgt", label);
jump(IFGT, label, 1);
}
/**
* Generate an if_icmpgt
*
* @param label label to true case
*/
void if_icmpgt(final Label label) {
debug("if_icmpgt", label);
jump(IF_ICMPGT, label, 2);
}
/**
* Generate an ifge
*
* @param label label to true case
*/
void ifge(final Label label) {
debug("ifge", label);
jump(IFGE, label, 1);
}
/**
* Generate an if_icmpge
*
* @param label label to true case
*/
void if_icmpge(final Label label) {
debug("if_icmpge", label);
jump(IF_ICMPGE, label, 2);
}
/**
* Unconditional jump to a label
*
* @param label destination label
*/
void _goto(final Label label) {
debug("goto", label);
jump(GOTO, label, 0);
doesNotContinueSequentially(); //whoever reaches the point after us provides the stack, because we don't
}
/**
* Unconditional jump to the start label of a loop. It differs from ordinary {@link #_goto(Label)} in that it will
* preserve the current label stack, as the next instruction after the goto is loop body that the loop will come
* back to. Also used to jump at the start label of the continuation handler, as it behaves much like a loop test in
* the sense that after it is evaluated, it also jumps backwards.
*
* @param loopStart start label of a loop
*/
void gotoLoopStart(final Label loopStart) {
debug("goto (loop)", loopStart);
jump(GOTO, loopStart, 0);
}
/**
* Unconditional jump without any control flow and data flow testing. You should not normally use this method when
* generating code, except if you're very sure that you know what you're doing. Normally only used for the
* admittedly torturous control flow of continuation handler plumbing.
* @param target the target of the jump
*/
void uncheckedGoto(final Label target) {
method.visitJumpInsn(GOTO, target.getLabel());
}
/**
* Potential transfer of control to a catch block.
*
* @param catchLabel destination catch label
*/
void canThrow(final Label catchLabel) {
catchLabel.joinFromTry(stack, false);
}
/**
* A join in control flow - helper function that makes sure all entry stacks
* discovered for the join point so far are equivalent
*
* MergeStack: we are about to enter a label. If its stack, label.getStack() is null
* we have never been here before. Then we are expected to carry a stack with us.
*
* @param label label
*/
private void joinTo(final Label label) {
assert isReachable();
label.joinFrom(stack);
}
/**
* Register a new label, enter it here.
* @param label
*/
void label(final Label label) {
breakLabel(label, -1);
}
/**
* Register a new break target label, enter it here.
*
* @param label the label
* @param liveLocals the number of live locals at this label
*/
void breakLabel(final Label label, final int liveLocals) {
if (!isReachable()) {
// If we emit a label, and the label's stack is null, it must not be reachable.
assert (label.getStack() == null) != label.isReachable();
} else {
joinTo(label);
}
// Use label's stack as we might have no stack.
final Label.Stack labelStack = label.getStack();
stack = labelStack == null ? null : labelStack.clone();
if(stack != null && label.isBreakTarget() && liveLocals != -1) {
// This has to be done because we might not have another frame to provide us with its firstTemp if the label
// is only reachable through a break or continue statement; also in this case, the frame can actually
// give us a higher number of live locals, e.g. if it comes from a catch. Typical example:
// for(;;) { try{ throw 0; } catch(e) { break; } }.
// Since the for loop can only be exited through the break in the catch block, it'll bring with it the
// "e" as a live local, and we need to trim it off here.
assert stack.firstTemp >= liveLocals;
stack.firstTemp = liveLocals;
}
debug_label(label);
method.visitLabel(label.getLabel());
}
/**
* Pop element from stack, convert to given type
*
* @param to type to convert to
*
* @return the method emitter
*/
MethodEmitter convert(final Type to) {
final Type from = peekType();
final Type type = from.convert(method, to);
if (type != null) {
if (!from.isEquivalentTo(to)) {
debug("convert", from, "->", to);
}
if (type != from) {
final int l0 = stack.getTopLocalLoad();
popType();
pushType(type);
// NOTE: conversions from a primitive type are considered to preserve the "load" property of the value
// on the stack. Otherwise we could introduce temporary locals in a deoptimized rest-of (e.g. doing an
// "i < x.length" where "i" is int and ".length" gets deoptimized to long would end up converting i to
// long with "ILOAD i; I2L; LSTORE tmp; LLOAD tmp;"). Such additional temporary would cause an error
// when restoring the state of the function for rest-of execution, as the not-yet deoptimized variant
// would have the (now invalidated) assumption that "x.length" is an int, so it wouldn't have the I2L,
// and therefore neither the subsequent LSTORE tmp; LLOAD tmp;. By making sure conversions from a
// primitive type don't erase the "load" information, we don't introduce temporaries in the deoptimized
// rest-of that didn't exist in the more optimistic version that triggered the deoptimization.
// NOTE: as a more general observation, we could theoretically track the operations required to
// reproduce any stack value as long as they are all local loads, constant loads, and stack operations.
// We won't go there in the current system
if(!from.isObject()) {
stack.markLocalLoad(l0);
}
}
}
return this;
}
/**
* Helper function - expect two types that are equivalent
*
* @return common type
*/
private Type get2() {
final Type p0 = popType();
final Type p1 = popType();
assert p0.isEquivalentTo(p1) : "expecting equivalent types on stack but got " + p0 + " and " + p1;
return p0;
}
/**
* Helper function - expect two types that are integer types and equivalent
*
* @return common type
*/
private BitwiseType get2i() {
final BitwiseType p0 = popBitwise();
final BitwiseType p1 = popBitwise();
assert p0.isEquivalentTo(p1) : "expecting equivalent types on stack but got " + p0 + " and " + p1;
return p0;
}
/**
* Helper function - expect two types that are numbers and equivalent
*
* @return common type
*/
private NumericType get2n() {
final NumericType p0 = popNumeric();
final NumericType p1 = popNumeric();
assert p0.isEquivalentTo(p1) : "expecting equivalent types on stack but got " + p0 + " and " + p1;
return p0;
}
/**
* Pop two numbers, perform addition and push result
*
* @return the method emitter
*/
MethodEmitter add(final int programPoint) {
debug("add");
pushType(get2().add(method, programPoint));
return this;
}
/**
* Pop two numbers, perform subtraction and push result
*
* @return the method emitter
*/
MethodEmitter sub(final int programPoint) {
debug("sub");
pushType(get2n().sub(method, programPoint));
return this;
}
/**
* Pop two numbers, perform multiplication and push result
*
* @return the method emitter
*/
MethodEmitter mul(final int programPoint) {
debug("mul ");
pushType(get2n().mul(method, programPoint));
return this;
}
/**
* Pop two numbers, perform division and push result
*
* @return the method emitter
*/
MethodEmitter div(final int programPoint) {
debug("div");
pushType(get2n().div(method, programPoint));
return this;
}
/**
* Pop two numbers, calculate remainder and push result
*
* @return the method emitter
*/
MethodEmitter rem(final int programPoint) {
debug("rem");
pushType(get2n().rem(method, programPoint));
return this;
}
/**
* Retrieve the top <tt>count</tt> types on the stack without modifying it.
*
* @param count number of types to return
* @return array of Types
*/
protected Type[] getTypesFromStack(final int count) {
return stack.getTopTypes(count);
}
int[] getLocalLoadsOnStack(final int from, final int to) {
return stack.getLocalLoads(from, to);
}
int getStackSize() {
return stack.size();
}
int getFirstTemp() {
return stack.firstTemp;
}
int getUsedSlotsWithLiveTemporaries() {
return stack.getUsedSlotsWithLiveTemporaries();
}
/**
* Helper function to generate a function signature based on stack contents
* and argument count and return type
*
* @param returnType return type
* @param argCount argument count
*
* @return function signature for stack contents
*/
private String getDynamicSignature(final Type returnType, final int argCount) {
final Type[] paramTypes = new Type[argCount];
int pos = 0;
for (int i = argCount - 1; i >= 0; i--) {
Type pt = stack.peek(pos++);
// "erase" specific ScriptObject subtype info - except for NativeArray.
// NativeArray is used for array/List/Deque conversion for Java calls.
if (ScriptObject.class.isAssignableFrom(pt.getTypeClass()) &&
!NativeArray.class.isAssignableFrom(pt.getTypeClass())) {
pt = Type.SCRIPT_OBJECT;
}
paramTypes[i] = pt;
}
final String descriptor = Type.getMethodDescriptor(returnType, paramTypes);
for (int i = 0; i < argCount; i++) {
popType(paramTypes[argCount - i - 1]);
}
return descriptor;
}
MethodEmitter invalidateSpecialName(final String name) {
switch (name) {
case "apply":
case "call":
debug("invalidate_name", "name=", name);
load("Function");
invoke(ScriptRuntime.INVALIDATE_RESERVED_BUILTIN_NAME);
break;
default:
break;
}
return this;
}
/**
* Generate a dynamic new
*
* @param argCount number of arguments
* @param flags callsite flags
*
* @return the method emitter
*/
MethodEmitter dynamicNew(final int argCount, final int flags) {
return dynamicNew(argCount, flags, null);
}
/**
* Generate a dynamic new
*
* @param argCount number of arguments
* @param flags callsite flags
* @param msg additional message to be used when reporting error
*
* @return the method emitter
*/
MethodEmitter dynamicNew(final int argCount, final int flags, final String msg) {
assert !isOptimistic(flags);
debug("dynamic_new", "argcount=", argCount);
final String signature = getDynamicSignature(Type.OBJECT, argCount);
method.visitInvokeDynamicInsn(
msg != null && msg.length() < LARGE_STRING_THRESHOLD? "dyn:new:" + NameCodec.encode(msg) : "dyn:new",
signature, LINKERBOOTSTRAP, flags);
pushType(Type.OBJECT); //TODO fix result type
return this;
}
/**
* Generate a dynamic call
*
* @param returnType return type
* @param argCount number of arguments
* @param flags callsite flags
*
* @return the method emitter
*/
MethodEmitter dynamicCall(final Type returnType, final int argCount, final int flags) {
return dynamicCall(returnType, argCount, flags, null);
}
/**
* Generate a dynamic call
*
* @param returnType return type
* @param argCount number of arguments
* @param flags callsite flags
* @param msg additional message to be used when reporting error
*
* @return the method emitter
*/
MethodEmitter dynamicCall(final Type returnType, final int argCount, final int flags, final String msg) {
debug("dynamic_call", "args=", argCount, "returnType=", returnType);
final String signature = getDynamicSignature(returnType, argCount); // +1 because the function itself is the 1st parameter for dynamic calls (what you call - call target)
debug(" signature", signature);
method.visitInvokeDynamicInsn(
msg != null && msg.length() < LARGE_STRING_THRESHOLD? "dyn:call:" + NameCodec.encode(msg) : "dyn:call",
signature, LINKERBOOTSTRAP, flags);
pushType(returnType);
return this;
}
MethodEmitter dynamicArrayPopulatorCall(final int argCount, final int startIndex) {
debug("populate_array", "args=", argCount, "startIndex=", startIndex);
final String signature = getDynamicSignature(Type.OBJECT_ARRAY, argCount);
method.visitInvokeDynamicInsn("populateArray", signature, POPULATE_ARRAY_BOOTSTRAP, startIndex);
pushType(Type.OBJECT_ARRAY);
return this;
}
/**
* Generate dynamic getter. Pop scope from stack. Push result
*
* @param valueType type of the value to set
* @param name name of property
* @param flags call site flags
* @param isMethod should it prefer retrieving methods
* @param isIndex is this an index operation?
* @return the method emitter
*/
MethodEmitter dynamicGet(final Type valueType, final String name, final int flags, final boolean isMethod, final boolean isIndex) {
if (name.length() > LARGE_STRING_THRESHOLD) { // use getIndex for extremely long names
return load(name).dynamicGetIndex(valueType, flags, isMethod);
}
debug("dynamic_get", name, valueType, getProgramPoint(flags));
Type type = valueType;
if (type.isObject() || type.isBoolean()) {
type = Type.OBJECT; //promote e.g strings to object generic setter
}
popType(Type.SCOPE);
method.visitInvokeDynamicInsn(dynGetOperation(isMethod, isIndex) + ':' + NameCodec.encode(name),
Type.getMethodDescriptor(type, Type.OBJECT), LINKERBOOTSTRAP, flags);
pushType(type);
convert(valueType); //most probably a nop
return this;
}
/**
* Generate dynamic setter. Pop receiver and property from stack.
*
* @param name name of property
* @param flags call site flags
* @param isIndex is this an index operation?
*/
void dynamicSet(final String name, final int flags, final boolean isIndex) {
if (name.length() > LARGE_STRING_THRESHOLD) { // use setIndex for extremely long names
load(name).swap().dynamicSetIndex(flags);
return;
}
assert !isOptimistic(flags);
debug("dynamic_set", name, peekType());
Type type = peekType();
if (type.isObject() || type.isBoolean()) { //promote strings to objects etc
type = Type.OBJECT;
convert(Type.OBJECT); //TODO bad- until we specialize boolean setters,
}
popType(type);
popType(Type.SCOPE);
method.visitInvokeDynamicInsn(dynSetOperation(isIndex) + ':' + NameCodec.encode(name),
methodDescriptor(void.class, Object.class, type.getTypeClass()), LINKERBOOTSTRAP, flags);
}
/**
* Dynamic getter for indexed structures. Pop index and receiver from stack,
* generate appropriate signatures based on types
*
* @param result result type for getter
* @param flags call site flags for getter
* @param isMethod should it prefer retrieving methods
*
* @return the method emitter
*/
MethodEmitter dynamicGetIndex(final Type result, final int flags, final boolean isMethod) {
assert result.getTypeClass().isPrimitive() || result.getTypeClass() == Object.class;
debug("dynamic_get_index", peekType(1), "[", peekType(), "]", getProgramPoint(flags));
Type resultType = result;
if (result.isBoolean()) {
resultType = Type.OBJECT; // INT->OBJECT to avoid another dimension of cross products in the getters. TODO
}
Type index = peekType();
if (index.isObject() || index.isBoolean()) {
index = Type.OBJECT; //e.g. string->object
convert(Type.OBJECT);
}
popType();
popType(Type.OBJECT);
final String signature = Type.getMethodDescriptor(resultType, Type.OBJECT /*e.g STRING->OBJECT*/, index);
method.visitInvokeDynamicInsn(dynGetOperation(isMethod, true), signature, LINKERBOOTSTRAP, flags);
pushType(resultType);
if (result.isBoolean()) {
convert(Type.BOOLEAN);
}
return this;
}
private static String getProgramPoint(final int flags) {
if((flags & CALLSITE_OPTIMISTIC) == 0) {
return "";
}
return "pp=" + String.valueOf((flags & (-1 << CALLSITE_PROGRAM_POINT_SHIFT)) >> CALLSITE_PROGRAM_POINT_SHIFT);
}
/**
* Dynamic setter for indexed structures. Pop value, index and receiver from
* stack, generate appropriate signature based on types
*
* @param flags call site flags for setter
*/
void dynamicSetIndex(final int flags) {
assert !isOptimistic(flags);
debug("dynamic_set_index", peekType(2), "[", peekType(1), "] =", peekType());
Type value = peekType();
if (value.isObject() || value.isBoolean()) {
value = Type.OBJECT; //e.g. STRING->OBJECT - one descriptor for all object types
convert(Type.OBJECT);
}
popType();
Type index = peekType();
if (index.isObject() || index.isBoolean()) {
index = Type.OBJECT; //e.g. string->object
convert(Type.OBJECT);
}
popType(index);
final Type receiver = popType(Type.OBJECT);
assert receiver.isObject();
method.visitInvokeDynamicInsn("dyn:setElem|setProp", methodDescriptor(void.class, receiver.getTypeClass(), index.getTypeClass(), value.getTypeClass()), LINKERBOOTSTRAP, flags);
}
/**
* Load a key value in the proper form.
*
* @param key
*/
//TODO move this and break it apart
MethodEmitter loadKey(final Object key) {
if (key instanceof IdentNode) {
method.visitLdcInsn(((IdentNode) key).getName());
} else if (key instanceof LiteralNode) {
method.visitLdcInsn(((LiteralNode<?>)key).getString());
} else {
method.visitLdcInsn(JSType.toString(key));
}
pushType(Type.OBJECT); //STRING
return this;
}
@SuppressWarnings("fallthrough")
private static Type fieldType(final String desc) {
switch (desc) {
case "Z":
case "B":
case "C":
case "S":
case "I":
return Type.INT;
case "F":
assert false;
case "D":
return Type.NUMBER;
case "J":
return Type.LONG;
default:
assert desc.startsWith("[") || desc.startsWith("L") : desc + " is not an object type";
switch (desc.charAt(0)) {
case 'L':
return Type.OBJECT;
case '[':
return Type.typeFor(Array.newInstance(fieldType(desc.substring(1)).getTypeClass(), 0).getClass());
default:
assert false;
}
return Type.OBJECT;
}
}
/**
* Generate get for a field access
*
* @param fa the field access
*
* @return the method emitter
*/
MethodEmitter getField(final FieldAccess fa) {
return fa.get(this);
}
/**
* Generate set for a field access
*
* @param fa the field access
*/
void putField(final FieldAccess fa) {
fa.put(this);
}
/**
* Get the value of a non-static field, pop the receiver from the stack,
* push value to the stack
*
* @param className class
* @param fieldName field name
* @param fieldDescriptor field descriptor
*
* @return the method emitter
*/
MethodEmitter getField(final String className, final String fieldName, final String fieldDescriptor) {
debug("getfield", "receiver=", peekType(), className, ".", fieldName, fieldDescriptor);
final Type receiver = popType();
assert receiver.isObject();
method.visitFieldInsn(GETFIELD, className, fieldName, fieldDescriptor);
pushType(fieldType(fieldDescriptor));
return this;
}
/**
* Get the value of a static field, push it to the stack
*
* @param className class
* @param fieldName field name
* @param fieldDescriptor field descriptor
*
* @return the method emitter
*/
MethodEmitter getStatic(final String className, final String fieldName, final String fieldDescriptor) {
debug("getstatic", className, ".", fieldName, ".", fieldDescriptor);
method.visitFieldInsn(GETSTATIC, className, fieldName, fieldDescriptor);
pushType(fieldType(fieldDescriptor));
return this;
}
/**
* Pop value and field from stack and write to a non-static field
*
* @param className class
* @param fieldName field name
* @param fieldDescriptor field descriptor
*/
void putField(final String className, final String fieldName, final String fieldDescriptor) {
debug("putfield", "receiver=", peekType(1), "value=", peekType());
popType(fieldType(fieldDescriptor));
popType(Type.OBJECT);
method.visitFieldInsn(PUTFIELD, className, fieldName, fieldDescriptor);
}
/**
* Pop value from stack and write to a static field
*
* @param className class
* @param fieldName field name
* @param fieldDescriptor field descriptor
*/
void putStatic(final String className, final String fieldName, final String fieldDescriptor) {
debug("putfield", "value=", peekType());
popType(fieldType(fieldDescriptor));
method.visitFieldInsn(PUTSTATIC, className, fieldName, fieldDescriptor);
}
/**
* Register line number at a label
*
* @param line line number
*/
void lineNumber(final int line) {
if (context.getEnv()._debug_lines) {
debug_label("[LINE]", line);
final jdk.internal.org.objectweb.asm.Label l = new jdk.internal.org.objectweb.asm.Label();
method.visitLabel(l);
method.visitLineNumber(line, l);
}
}
void beforeJoinPoint(final JoinPredecessor joinPredecessor) {
LocalVariableConversion next = joinPredecessor.getLocalVariableConversion();
while(next != null) {
final Symbol symbol = next.getSymbol();
if(next.isLive()) {
emitLocalVariableConversion(next, true);
} else {
markDeadLocalVariable(symbol);
}
next = next.getNext();
}
}
void beforeTry(final TryNode tryNode, final Label recovery) {
LocalVariableConversion next = tryNode.getLocalVariableConversion();
while(next != null) {
if(next.isLive()) {
final Type to = emitLocalVariableConversion(next, false);
recovery.getStack().onLocalStore(to, next.getSymbol().getSlot(to), true);
}
next = next.getNext();
}
}
private static String dynGetOperation(final boolean isMethod, final boolean isIndex) {
if (isMethod) {
return isIndex ? "dyn:getMethod|getElem|getProp" : "dyn:getMethod|getProp|getElem";
} else {
return isIndex ? "dyn:getElem|getProp|getMethod" : "dyn:getProp|getElem|getMethod";
}
}
private static String dynSetOperation(final boolean isIndex) {
return isIndex ? "dyn:setElem|setProp" : "dyn:setProp|setElem";
}
private Type emitLocalVariableConversion(final LocalVariableConversion conversion, final boolean onlySymbolLiveValue) {
final Type from = conversion.getFrom();
final Type to = conversion.getTo();
final Symbol symbol = conversion.getSymbol();
assert symbol.isBytecodeLocal();
if(from == Type.UNDEFINED) {
loadUndefined(to);
} else {
load(symbol, from).convert(to);
}
store(symbol, to, onlySymbolLiveValue);
return to;
}
/*
* Debugging below
*/
private final FieldAccess ERR_STREAM = staticField(System.class, "err", PrintStream.class);
private final Call PRINT = virtualCallNoLookup(PrintStream.class, "print", void.class, Object.class);
private final Call PRINTLN = virtualCallNoLookup(PrintStream.class, "println", void.class, Object.class);
private final Call PRINT_STACKTRACE = virtualCallNoLookup(Throwable.class, "printStackTrace", void.class);
/**
* Emit a System.err.print statement of whatever is on top of the bytecode stack
*/
void print() {
getField(ERR_STREAM);
swap();
convert(Type.OBJECT);
invoke(PRINT);
}
/**
* Emit a System.err.println statement of whatever is on top of the bytecode stack
*/
void println() {
getField(ERR_STREAM);
swap();
convert(Type.OBJECT);
invoke(PRINTLN);
}
/**
* Emit a System.err.print statement
* @param string string to print
*/
void print(final String string) {
getField(ERR_STREAM);
load(string);
invoke(PRINT);
}
/**
* Emit a System.err.println statement
* @param string string to print
*/
void println(final String string) {
getField(ERR_STREAM);
load(string);
invoke(PRINTLN);
}
/**
* Print a stacktrace to S
*/
void stacktrace() {
_new(Throwable.class);
dup();
invoke(constructorNoLookup(Throwable.class));
invoke(PRINT_STACKTRACE);
}
private static int linePrefix = 0;
/**
* Debug function that outputs generated bytecode and stack contents
*
* @param args debug information to print
*/
@SuppressWarnings("unused")
private void debug(final Object... args) {
if (debug) {
debug(30, args);
}
}
private void debug(final String arg) {
if (debug) {
debug(30, arg);
}
}
private void debug(final Object arg0, final Object arg1) {
if (debug) {
debug(30, new Object[] { arg0, arg1 });
}
}
private void debug(final Object arg0, final Object arg1, final Object arg2) {
if (debug) {
debug(30, new Object[] { arg0, arg1, arg2 });
}
}
private void debug(final Object arg0, final Object arg1, final Object arg2, final Object arg3) {
if (debug) {
debug(30, new Object[] { arg0, arg1, arg2, arg3 });
}
}
private void debug(final Object arg0, final Object arg1, final Object arg2, final Object arg3, final Object arg4) {
if (debug) {
debug(30, new Object[] { arg0, arg1, arg2, arg3, arg4 });
}
}
private void debug(final Object arg0, final Object arg1, final Object arg2, final Object arg3, final Object arg4, final Object arg5) {
if (debug) {
debug(30, new Object[] { arg0, arg1, arg2, arg3, arg4, arg5 });
}
}
private void debug(final Object arg0, final Object arg1, final Object arg2, final Object arg3, final Object arg4, final Object arg5, final Object arg6) {
if (debug) {
debug(30, new Object[] { arg0, arg1, arg2, arg3, arg4, arg5, arg6 });
}
}
/**
* Debug function that outputs generated bytecode and stack contents
* for a label - indentation is currently the only thing that differs
*
* @param args debug information to print
*/
private void debug_label(final Object... args) {
if (debug) {
debug(22, args);
}
}
private void debug(final int padConstant, final Object... args) {
if (debug) {
final StringBuilder sb = new StringBuilder();
int pad;
sb.append('#');
sb.append(++linePrefix);
pad = 5 - sb.length();
while (pad > 0) {
sb.append(' ');
pad--;
}
if (isReachable() && !stack.isEmpty()) {
sb.append("{");
sb.append(stack.size());
sb.append(":");
for (int pos = 0; pos < stack.size(); pos++) {
final Type t = stack.peek(pos);
if (t == Type.SCOPE) {
sb.append("scope");
} else if (t == Type.THIS) {
sb.append("this");
} else if (t.isObject()) {
String desc = t.getDescriptor();
int i;
for (i = 0; desc.charAt(i) == '[' && i < desc.length(); i++) {
sb.append('[');
}
desc = desc.substring(i);
final int slash = desc.lastIndexOf('/');
if (slash != -1) {
desc = desc.substring(slash + 1, desc.length() - 1);
}
if ("Object".equals(desc)) {
sb.append('O');
} else {
sb.append(desc);
}
} else {
sb.append(t.getDescriptor());
}
final int loadIndex = stack.localLoads[stack.sp - 1 - pos];
if(loadIndex != Label.Stack.NON_LOAD) {
sb.append('(').append(loadIndex).append(')');
}
if (pos + 1 < stack.size()) {
sb.append(' ');
}
}
sb.append('}');
sb.append(' ');
}
pad = padConstant - sb.length();
while (pad > 0) {
sb.append(' ');
pad--;
}
for (final Object arg : args) {
sb.append(arg);
sb.append(' ');
}
if (context.getEnv() != null) { //early bootstrap code doesn't have inited context yet
log.info(sb);
if (DEBUG_TRACE_LINE == linePrefix) {
new Throwable().printStackTrace(log.getOutputStream());
}
}
}
}
/**
* Set the current function node being emitted
* @param functionNode the function node
*/
void setFunctionNode(final FunctionNode functionNode) {
this.functionNode = functionNode;
}
/**
* Invoke to enforce assertions preventing load from a local variable slot that's known to not have been written to.
* Used by CodeGenerator, as it strictly enforces tracking of stores. Simpler uses of MethodEmitter, e.g. those
* for creating initializers for structure classes, array getters, etc. don't have strict tracking of stores,
* therefore they would fail if they had this assertion turned on.
*/
void setPreventUndefinedLoad() {
this.preventUndefinedLoad = true;
}
private static boolean isOptimistic(final int flags) {
return (flags & CALLSITE_OPTIMISTIC) != 0;
}
}