| /* |
| * Copyright (c) 1999, 2016, 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. |
| * |
| * 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. |
| * |
| */ |
| |
| #include "precompiled.hpp" |
| #include "c1/c1_Canonicalizer.hpp" |
| #include "c1/c1_InstructionPrinter.hpp" |
| #include "c1/c1_ValueStack.hpp" |
| #include "ci/ciArray.hpp" |
| #include "runtime/sharedRuntime.hpp" |
| |
| |
| class PrintValueVisitor: public ValueVisitor { |
| void visit(Value* vp) { |
| (*vp)->print_line(); |
| } |
| }; |
| |
| void Canonicalizer::set_canonical(Value x) { |
| assert(x != NULL, "value must exist"); |
| // Note: we can not currently substitute root nodes which show up in |
| // the instruction stream (because the instruction list is embedded |
| // in the instructions). |
| if (canonical() != x) { |
| #ifndef PRODUCT |
| if (!x->has_printable_bci()) { |
| x->set_printable_bci(bci()); |
| } |
| #endif |
| if (PrintCanonicalization) { |
| PrintValueVisitor do_print_value; |
| canonical()->input_values_do(&do_print_value); |
| canonical()->print_line(); |
| tty->print_cr("canonicalized to:"); |
| x->input_values_do(&do_print_value); |
| x->print_line(); |
| tty->cr(); |
| } |
| assert(_canonical->type()->tag() == x->type()->tag(), "types must match"); |
| _canonical = x; |
| } |
| } |
| |
| |
| void Canonicalizer::move_const_to_right(Op2* x) { |
| if (x->x()->type()->is_constant() && x->is_commutative()) x->swap_operands(); |
| } |
| |
| |
| void Canonicalizer::do_Op2(Op2* x) { |
| if (x->x() == x->y()) { |
| switch (x->op()) { |
| case Bytecodes::_isub: set_constant(0); return; |
| case Bytecodes::_lsub: set_constant(jlong_cast(0)); return; |
| case Bytecodes::_iand: // fall through |
| case Bytecodes::_land: // fall through |
| case Bytecodes::_ior: // fall through |
| case Bytecodes::_lor : set_canonical(x->x()); return; |
| case Bytecodes::_ixor: set_constant(0); return; |
| case Bytecodes::_lxor: set_constant(jlong_cast(0)); return; |
| } |
| } |
| |
| if (x->x()->type()->is_constant() && x->y()->type()->is_constant()) { |
| // do constant folding for selected operations |
| switch (x->type()->tag()) { |
| case intTag: |
| { jint a = x->x()->type()->as_IntConstant()->value(); |
| jint b = x->y()->type()->as_IntConstant()->value(); |
| switch (x->op()) { |
| case Bytecodes::_iadd: set_constant(a + b); return; |
| case Bytecodes::_isub: set_constant(a - b); return; |
| case Bytecodes::_imul: set_constant(a * b); return; |
| case Bytecodes::_idiv: |
| if (b != 0) { |
| if (a == min_jint && b == -1) { |
| set_constant(min_jint); |
| } else { |
| set_constant(a / b); |
| } |
| return; |
| } |
| break; |
| case Bytecodes::_irem: |
| if (b != 0) { |
| if (a == min_jint && b == -1) { |
| set_constant(0); |
| } else { |
| set_constant(a % b); |
| } |
| return; |
| } |
| break; |
| case Bytecodes::_iand: set_constant(a & b); return; |
| case Bytecodes::_ior : set_constant(a | b); return; |
| case Bytecodes::_ixor: set_constant(a ^ b); return; |
| } |
| } |
| break; |
| case longTag: |
| { jlong a = x->x()->type()->as_LongConstant()->value(); |
| jlong b = x->y()->type()->as_LongConstant()->value(); |
| switch (x->op()) { |
| case Bytecodes::_ladd: set_constant(a + b); return; |
| case Bytecodes::_lsub: set_constant(a - b); return; |
| case Bytecodes::_lmul: set_constant(a * b); return; |
| case Bytecodes::_ldiv: |
| if (b != 0) { |
| set_constant(SharedRuntime::ldiv(b, a)); |
| return; |
| } |
| break; |
| case Bytecodes::_lrem: |
| if (b != 0) { |
| set_constant(SharedRuntime::lrem(b, a)); |
| return; |
| } |
| break; |
| case Bytecodes::_land: set_constant(a & b); return; |
| case Bytecodes::_lor : set_constant(a | b); return; |
| case Bytecodes::_lxor: set_constant(a ^ b); return; |
| } |
| } |
| break; |
| // other cases not implemented (must be extremely careful with floats & doubles!) |
| } |
| } |
| // make sure constant is on the right side, if any |
| move_const_to_right(x); |
| |
| if (x->y()->type()->is_constant()) { |
| // do constant folding for selected operations |
| switch (x->type()->tag()) { |
| case intTag: |
| if (x->y()->type()->as_IntConstant()->value() == 0) { |
| switch (x->op()) { |
| case Bytecodes::_iadd: set_canonical(x->x()); return; |
| case Bytecodes::_isub: set_canonical(x->x()); return; |
| case Bytecodes::_imul: set_constant(0); return; |
| // Note: for div and rem, make sure that C semantics |
| // corresponds to Java semantics! |
| case Bytecodes::_iand: set_constant(0); return; |
| case Bytecodes::_ior : set_canonical(x->x()); return; |
| } |
| } |
| break; |
| case longTag: |
| if (x->y()->type()->as_LongConstant()->value() == (jlong)0) { |
| switch (x->op()) { |
| case Bytecodes::_ladd: set_canonical(x->x()); return; |
| case Bytecodes::_lsub: set_canonical(x->x()); return; |
| case Bytecodes::_lmul: set_constant((jlong)0); return; |
| // Note: for div and rem, make sure that C semantics |
| // corresponds to Java semantics! |
| case Bytecodes::_land: set_constant((jlong)0); return; |
| case Bytecodes::_lor : set_canonical(x->x()); return; |
| } |
| } |
| break; |
| } |
| } |
| } |
| |
| |
| void Canonicalizer::do_Phi (Phi* x) {} |
| void Canonicalizer::do_Constant (Constant* x) {} |
| void Canonicalizer::do_Local (Local* x) {} |
| void Canonicalizer::do_LoadField (LoadField* x) {} |
| |
| // checks if v is in the block that is currently processed by |
| // GraphBuilder. This is the only block that has not BlockEnd yet. |
| static bool in_current_block(Value v) { |
| int max_distance = 4; |
| while (max_distance > 0 && v != NULL && v->as_BlockEnd() == NULL) { |
| v = v->next(); |
| max_distance--; |
| } |
| return v == NULL; |
| } |
| |
| void Canonicalizer::do_StoreField (StoreField* x) { |
| // If a value is going to be stored into a field or array some of |
| // the conversions emitted by javac are unneeded because the fields |
| // are packed to their natural size. |
| Convert* conv = x->value()->as_Convert(); |
| if (conv) { |
| Value value = NULL; |
| BasicType type = x->field()->type()->basic_type(); |
| switch (conv->op()) { |
| case Bytecodes::_i2b: if (type == T_BYTE) value = conv->value(); break; |
| case Bytecodes::_i2s: if (type == T_SHORT || type == T_BYTE) value = conv->value(); break; |
| case Bytecodes::_i2c: if (type == T_CHAR || type == T_BYTE) value = conv->value(); break; |
| } |
| // limit this optimization to current block |
| if (value != NULL && in_current_block(conv)) { |
| set_canonical(new StoreField(x->obj(), x->offset(), x->field(), value, x->is_static(), |
| x->state_before(), x->needs_patching())); |
| return; |
| } |
| } |
| |
| } |
| |
| void Canonicalizer::do_ArrayLength (ArrayLength* x) { |
| NewArray* array = x->array()->as_NewArray(); |
| if (array != NULL && array->length() != NULL) { |
| Constant* length = array->length()->as_Constant(); |
| if (length != NULL) { |
| // do not use the Constant itself, but create a new Constant |
| // with same value Otherwise a Constant is live over multiple |
| // blocks without being registered in a state array. |
| assert(length->type()->as_IntConstant() != NULL, "array length must be integer"); |
| set_constant(length->type()->as_IntConstant()->value()); |
| } |
| } else { |
| LoadField* lf = x->array()->as_LoadField(); |
| if (lf != NULL) { |
| ciField* field = lf->field(); |
| if (field->is_constant() && field->is_static()) { |
| // final static field |
| ciObject* c = field->constant_value().as_object(); |
| if (c->is_array()) { |
| ciArray* array = (ciArray*) c; |
| set_constant(array->length()); |
| } |
| } |
| } |
| } |
| } |
| |
| void Canonicalizer::do_LoadIndexed (LoadIndexed* x) {} |
| void Canonicalizer::do_StoreIndexed (StoreIndexed* x) { |
| // If a value is going to be stored into a field or array some of |
| // the conversions emitted by javac are unneeded because the fields |
| // are packed to their natural size. |
| Convert* conv = x->value()->as_Convert(); |
| if (conv) { |
| Value value = NULL; |
| BasicType type = x->elt_type(); |
| switch (conv->op()) { |
| case Bytecodes::_i2b: if (type == T_BYTE) value = conv->value(); break; |
| case Bytecodes::_i2s: if (type == T_SHORT || type == T_BYTE) value = conv->value(); break; |
| case Bytecodes::_i2c: if (type == T_CHAR || type == T_BYTE) value = conv->value(); break; |
| } |
| // limit this optimization to current block |
| if (value != NULL && in_current_block(conv)) { |
| set_canonical(new StoreIndexed(x->array(), x->index(), x->length(), |
| x->elt_type(), value, x->state_before(), |
| x->check_boolean())); |
| return; |
| } |
| } |
| |
| |
| } |
| |
| |
| void Canonicalizer::do_NegateOp(NegateOp* x) { |
| ValueType* t = x->x()->type(); |
| if (t->is_constant()) { |
| switch (t->tag()) { |
| case intTag : set_constant(-t->as_IntConstant ()->value()); return; |
| case longTag : set_constant(-t->as_LongConstant ()->value()); return; |
| case floatTag : set_constant(-t->as_FloatConstant ()->value()); return; |
| case doubleTag: set_constant(-t->as_DoubleConstant()->value()); return; |
| default : ShouldNotReachHere(); |
| } |
| } |
| } |
| |
| |
| void Canonicalizer::do_ArithmeticOp (ArithmeticOp* x) { do_Op2(x); } |
| |
| |
| void Canonicalizer::do_ShiftOp (ShiftOp* x) { |
| ValueType* t = x->x()->type(); |
| ValueType* t2 = x->y()->type(); |
| if (t->is_constant()) { |
| switch (t->tag()) { |
| case intTag : if (t->as_IntConstant()->value() == 0) { set_constant(0); return; } break; |
| case longTag : if (t->as_LongConstant()->value() == (jlong)0) { set_constant(jlong_cast(0)); return; } break; |
| default : ShouldNotReachHere(); |
| } |
| if (t2->is_constant()) { |
| if (t->tag() == intTag) { |
| int value = t->as_IntConstant()->value(); |
| int shift = t2->as_IntConstant()->value() & 31; |
| jint mask = ~(~0 << (32 - shift)); |
| if (shift == 0) mask = ~0; |
| switch (x->op()) { |
| case Bytecodes::_ishl: set_constant(value << shift); return; |
| case Bytecodes::_ishr: set_constant(value >> shift); return; |
| case Bytecodes::_iushr: set_constant((value >> shift) & mask); return; |
| } |
| } else if (t->tag() == longTag) { |
| jlong value = t->as_LongConstant()->value(); |
| int shift = t2->as_IntConstant()->value() & 63; |
| jlong mask = ~(~jlong_cast(0) << (64 - shift)); |
| if (shift == 0) mask = ~jlong_cast(0); |
| switch (x->op()) { |
| case Bytecodes::_lshl: set_constant(value << shift); return; |
| case Bytecodes::_lshr: set_constant(value >> shift); return; |
| case Bytecodes::_lushr: set_constant((value >> shift) & mask); return; |
| } |
| } |
| } |
| } |
| if (t2->is_constant()) { |
| switch (t2->tag()) { |
| case intTag : if (t2->as_IntConstant()->value() == 0) set_canonical(x->x()); return; |
| case longTag : if (t2->as_LongConstant()->value() == (jlong)0) set_canonical(x->x()); return; |
| default : ShouldNotReachHere(); |
| } |
| } |
| } |
| |
| |
| void Canonicalizer::do_LogicOp (LogicOp* x) { do_Op2(x); } |
| void Canonicalizer::do_CompareOp (CompareOp* x) { |
| if (x->x() == x->y()) { |
| switch (x->x()->type()->tag()) { |
| case longTag: set_constant(0); break; |
| case floatTag: { |
| FloatConstant* fc = x->x()->type()->as_FloatConstant(); |
| if (fc) { |
| if (g_isnan(fc->value())) { |
| set_constant(x->op() == Bytecodes::_fcmpl ? -1 : 1); |
| } else { |
| set_constant(0); |
| } |
| } |
| break; |
| } |
| case doubleTag: { |
| DoubleConstant* dc = x->x()->type()->as_DoubleConstant(); |
| if (dc) { |
| if (g_isnan(dc->value())) { |
| set_constant(x->op() == Bytecodes::_dcmpl ? -1 : 1); |
| } else { |
| set_constant(0); |
| } |
| } |
| break; |
| } |
| } |
| } else if (x->x()->type()->is_constant() && x->y()->type()->is_constant()) { |
| switch (x->x()->type()->tag()) { |
| case longTag: { |
| jlong vx = x->x()->type()->as_LongConstant()->value(); |
| jlong vy = x->y()->type()->as_LongConstant()->value(); |
| if (vx == vy) |
| set_constant(0); |
| else if (vx < vy) |
| set_constant(-1); |
| else |
| set_constant(1); |
| break; |
| } |
| |
| case floatTag: { |
| float vx = x->x()->type()->as_FloatConstant()->value(); |
| float vy = x->y()->type()->as_FloatConstant()->value(); |
| if (g_isnan(vx) || g_isnan(vy)) |
| set_constant(x->op() == Bytecodes::_fcmpl ? -1 : 1); |
| else if (vx == vy) |
| set_constant(0); |
| else if (vx < vy) |
| set_constant(-1); |
| else |
| set_constant(1); |
| break; |
| } |
| |
| case doubleTag: { |
| double vx = x->x()->type()->as_DoubleConstant()->value(); |
| double vy = x->y()->type()->as_DoubleConstant()->value(); |
| if (g_isnan(vx) || g_isnan(vy)) |
| set_constant(x->op() == Bytecodes::_dcmpl ? -1 : 1); |
| else if (vx == vy) |
| set_constant(0); |
| else if (vx < vy) |
| set_constant(-1); |
| else |
| set_constant(1); |
| break; |
| } |
| } |
| |
| } |
| } |
| |
| |
| void Canonicalizer::do_IfInstanceOf(IfInstanceOf* x) {} |
| |
| void Canonicalizer::do_IfOp(IfOp* x) { |
| // Caution: do not use do_Op2(x) here for now since |
| // we map the condition to the op for now! |
| move_const_to_right(x); |
| } |
| |
| |
| void Canonicalizer::do_Intrinsic (Intrinsic* x) { |
| switch (x->id()) { |
| case vmIntrinsics::_floatToRawIntBits : { |
| FloatConstant* c = x->argument_at(0)->type()->as_FloatConstant(); |
| if (c != NULL) { |
| JavaValue v; |
| v.set_jfloat(c->value()); |
| set_constant(v.get_jint()); |
| } |
| break; |
| } |
| case vmIntrinsics::_intBitsToFloat : { |
| IntConstant* c = x->argument_at(0)->type()->as_IntConstant(); |
| if (c != NULL) { |
| JavaValue v; |
| v.set_jint(c->value()); |
| set_constant(v.get_jfloat()); |
| } |
| break; |
| } |
| case vmIntrinsics::_doubleToRawLongBits : { |
| DoubleConstant* c = x->argument_at(0)->type()->as_DoubleConstant(); |
| if (c != NULL) { |
| JavaValue v; |
| v.set_jdouble(c->value()); |
| set_constant(v.get_jlong()); |
| } |
| break; |
| } |
| case vmIntrinsics::_longBitsToDouble : { |
| LongConstant* c = x->argument_at(0)->type()->as_LongConstant(); |
| if (c != NULL) { |
| JavaValue v; |
| v.set_jlong(c->value()); |
| set_constant(v.get_jdouble()); |
| } |
| break; |
| } |
| case vmIntrinsics::_isInstance : { |
| assert(x->number_of_arguments() == 2, "wrong type"); |
| |
| InstanceConstant* c = x->argument_at(0)->type()->as_InstanceConstant(); |
| if (c != NULL && !c->value()->is_null_object()) { |
| // ciInstance::java_mirror_type() returns non-NULL only for Java mirrors |
| ciType* t = c->value()->as_instance()->java_mirror_type(); |
| if (t->is_klass()) { |
| // substitute cls.isInstance(obj) of a constant Class into |
| // an InstantOf instruction |
| InstanceOf* i = new InstanceOf(t->as_klass(), x->argument_at(1), x->state_before()); |
| set_canonical(i); |
| // and try to canonicalize even further |
| do_InstanceOf(i); |
| } else { |
| assert(t->is_primitive_type(), "should be a primitive type"); |
| // cls.isInstance(obj) always returns false for primitive classes |
| set_constant(0); |
| } |
| } |
| break; |
| } |
| } |
| } |
| |
| void Canonicalizer::do_Convert (Convert* x) { |
| if (x->value()->type()->is_constant()) { |
| switch (x->op()) { |
| case Bytecodes::_i2b: set_constant((int)((x->value()->type()->as_IntConstant()->value() << 24) >> 24)); break; |
| case Bytecodes::_i2s: set_constant((int)((x->value()->type()->as_IntConstant()->value() << 16) >> 16)); break; |
| case Bytecodes::_i2c: set_constant((int)(x->value()->type()->as_IntConstant()->value() & ((1<<16)-1))); break; |
| case Bytecodes::_i2l: set_constant((jlong)(x->value()->type()->as_IntConstant()->value())); break; |
| case Bytecodes::_i2f: set_constant((float)(x->value()->type()->as_IntConstant()->value())); break; |
| case Bytecodes::_i2d: set_constant((double)(x->value()->type()->as_IntConstant()->value())); break; |
| case Bytecodes::_l2i: set_constant((int)(x->value()->type()->as_LongConstant()->value())); break; |
| case Bytecodes::_l2f: set_constant(SharedRuntime::l2f(x->value()->type()->as_LongConstant()->value())); break; |
| case Bytecodes::_l2d: set_constant(SharedRuntime::l2d(x->value()->type()->as_LongConstant()->value())); break; |
| case Bytecodes::_f2d: set_constant((double)(x->value()->type()->as_FloatConstant()->value())); break; |
| case Bytecodes::_f2i: set_constant(SharedRuntime::f2i(x->value()->type()->as_FloatConstant()->value())); break; |
| case Bytecodes::_f2l: set_constant(SharedRuntime::f2l(x->value()->type()->as_FloatConstant()->value())); break; |
| case Bytecodes::_d2f: set_constant((float)(x->value()->type()->as_DoubleConstant()->value())); break; |
| case Bytecodes::_d2i: set_constant(SharedRuntime::d2i(x->value()->type()->as_DoubleConstant()->value())); break; |
| case Bytecodes::_d2l: set_constant(SharedRuntime::d2l(x->value()->type()->as_DoubleConstant()->value())); break; |
| default: |
| ShouldNotReachHere(); |
| } |
| } |
| |
| Value value = x->value(); |
| BasicType type = T_ILLEGAL; |
| LoadField* lf = value->as_LoadField(); |
| if (lf) { |
| type = lf->field_type(); |
| } else { |
| LoadIndexed* li = value->as_LoadIndexed(); |
| if (li) { |
| type = li->elt_type(); |
| } else { |
| Convert* conv = value->as_Convert(); |
| if (conv) { |
| switch (conv->op()) { |
| case Bytecodes::_i2b: type = T_BYTE; break; |
| case Bytecodes::_i2s: type = T_SHORT; break; |
| case Bytecodes::_i2c: type = T_CHAR; break; |
| } |
| } |
| } |
| } |
| if (type != T_ILLEGAL) { |
| switch (x->op()) { |
| case Bytecodes::_i2b: if (type == T_BYTE) set_canonical(x->value()); break; |
| case Bytecodes::_i2s: if (type == T_SHORT || type == T_BYTE) set_canonical(x->value()); break; |
| case Bytecodes::_i2c: if (type == T_CHAR) set_canonical(x->value()); break; |
| } |
| } else { |
| Op2* op2 = x->value()->as_Op2(); |
| if (op2 && op2->op() == Bytecodes::_iand && op2->y()->type()->is_constant()) { |
| jint safebits = 0; |
| jint mask = op2->y()->type()->as_IntConstant()->value(); |
| switch (x->op()) { |
| case Bytecodes::_i2b: safebits = 0x7f; break; |
| case Bytecodes::_i2s: safebits = 0x7fff; break; |
| case Bytecodes::_i2c: safebits = 0xffff; break; |
| } |
| // When casting a masked integer to a smaller signed type, if |
| // the mask doesn't include the sign bit the cast isn't needed. |
| if (safebits && (mask & ~safebits) == 0) { |
| set_canonical(x->value()); |
| } |
| } |
| } |
| |
| } |
| |
| void Canonicalizer::do_NullCheck (NullCheck* x) { |
| if (x->obj()->as_NewArray() != NULL || x->obj()->as_NewInstance() != NULL) { |
| set_canonical(x->obj()); |
| } else { |
| Constant* con = x->obj()->as_Constant(); |
| if (con) { |
| ObjectType* c = con->type()->as_ObjectType(); |
| if (c && c->is_loaded()) { |
| ObjectConstant* oc = c->as_ObjectConstant(); |
| if (!oc || !oc->value()->is_null_object()) { |
| set_canonical(con); |
| } |
| } |
| } |
| } |
| } |
| |
| void Canonicalizer::do_TypeCast (TypeCast* x) {} |
| void Canonicalizer::do_Invoke (Invoke* x) {} |
| void Canonicalizer::do_NewInstance (NewInstance* x) {} |
| void Canonicalizer::do_NewTypeArray (NewTypeArray* x) {} |
| void Canonicalizer::do_NewObjectArray (NewObjectArray* x) {} |
| void Canonicalizer::do_NewMultiArray (NewMultiArray* x) {} |
| void Canonicalizer::do_CheckCast (CheckCast* x) { |
| if (x->klass()->is_loaded()) { |
| Value obj = x->obj(); |
| ciType* klass = obj->exact_type(); |
| if (klass == NULL) klass = obj->declared_type(); |
| if (klass != NULL && klass->is_loaded() && klass->is_subtype_of(x->klass())) { |
| set_canonical(obj); |
| return; |
| } |
| // checkcast of null returns null |
| if (obj->as_Constant() && obj->type()->as_ObjectType()->constant_value()->is_null_object()) { |
| set_canonical(obj); |
| } |
| } |
| } |
| void Canonicalizer::do_InstanceOf (InstanceOf* x) { |
| if (x->klass()->is_loaded()) { |
| Value obj = x->obj(); |
| ciType* exact = obj->exact_type(); |
| if (exact != NULL && exact->is_loaded() && (obj->as_NewInstance() || obj->as_NewArray())) { |
| set_constant(exact->is_subtype_of(x->klass()) ? 1 : 0); |
| return; |
| } |
| // instanceof null returns false |
| if (obj->as_Constant() && obj->type()->as_ObjectType()->constant_value()->is_null_object()) { |
| set_constant(0); |
| } |
| } |
| |
| } |
| void Canonicalizer::do_MonitorEnter (MonitorEnter* x) {} |
| void Canonicalizer::do_MonitorExit (MonitorExit* x) {} |
| void Canonicalizer::do_BlockBegin (BlockBegin* x) {} |
| void Canonicalizer::do_Goto (Goto* x) {} |
| |
| |
| static bool is_true(jlong x, If::Condition cond, jlong y) { |
| switch (cond) { |
| case If::eql: return x == y; |
| case If::neq: return x != y; |
| case If::lss: return x < y; |
| case If::leq: return x <= y; |
| case If::gtr: return x > y; |
| case If::geq: return x >= y; |
| } |
| ShouldNotReachHere(); |
| return false; |
| } |
| |
| static bool is_safepoint(BlockEnd* x, BlockBegin* sux) { |
| // An Instruction with multiple successors, x, is replaced by a Goto |
| // to a single successor, sux. Is a safepoint check needed = was the |
| // instruction being replaced a safepoint and the single remaining |
| // successor a back branch? |
| return x->is_safepoint() && (sux->bci() < x->state_before()->bci()); |
| } |
| |
| void Canonicalizer::do_If(If* x) { |
| // move const to right |
| if (x->x()->type()->is_constant()) x->swap_operands(); |
| // simplify |
| const Value l = x->x(); ValueType* lt = l->type(); |
| const Value r = x->y(); ValueType* rt = r->type(); |
| |
| if (l == r && !lt->is_float_kind()) { |
| // pattern: If (a cond a) => simplify to Goto |
| BlockBegin* sux = NULL; |
| switch (x->cond()) { |
| case If::eql: sux = x->sux_for(true); break; |
| case If::neq: sux = x->sux_for(false); break; |
| case If::lss: sux = x->sux_for(false); break; |
| case If::leq: sux = x->sux_for(true); break; |
| case If::gtr: sux = x->sux_for(false); break; |
| case If::geq: sux = x->sux_for(true); break; |
| default: ShouldNotReachHere(); |
| } |
| // If is a safepoint then the debug information should come from the state_before of the If. |
| set_canonical(new Goto(sux, x->state_before(), is_safepoint(x, sux))); |
| return; |
| } |
| |
| if (lt->is_constant() && rt->is_constant()) { |
| if (x->x()->as_Constant() != NULL) { |
| // pattern: If (lc cond rc) => simplify to: Goto |
| BlockBegin* sux = x->x()->as_Constant()->compare(x->cond(), x->y(), |
| x->sux_for(true), |
| x->sux_for(false)); |
| if (sux != NULL) { |
| // If is a safepoint then the debug information should come from the state_before of the If. |
| set_canonical(new Goto(sux, x->state_before(), is_safepoint(x, sux))); |
| } |
| } |
| } else if (rt->as_IntConstant() != NULL) { |
| // pattern: If (l cond rc) => investigate further |
| const jint rc = rt->as_IntConstant()->value(); |
| if (l->as_CompareOp() != NULL) { |
| // pattern: If ((a cmp b) cond rc) => simplify to: If (x cond y) or: Goto |
| CompareOp* cmp = l->as_CompareOp(); |
| bool unordered_is_less = cmp->op() == Bytecodes::_fcmpl || cmp->op() == Bytecodes::_dcmpl; |
| BlockBegin* lss_sux = x->sux_for(is_true(-1, x->cond(), rc)); // successor for a < b |
| BlockBegin* eql_sux = x->sux_for(is_true( 0, x->cond(), rc)); // successor for a = b |
| BlockBegin* gtr_sux = x->sux_for(is_true(+1, x->cond(), rc)); // successor for a > b |
| BlockBegin* nan_sux = unordered_is_less ? lss_sux : gtr_sux ; // successor for unordered |
| // Note: At this point all successors (lss_sux, eql_sux, gtr_sux, nan_sux) are |
| // equal to x->tsux() or x->fsux(). Furthermore, nan_sux equals either |
| // lss_sux or gtr_sux. |
| if (lss_sux == eql_sux && eql_sux == gtr_sux) { |
| // all successors identical => simplify to: Goto |
| set_canonical(new Goto(lss_sux, x->state_before(), x->is_safepoint())); |
| } else { |
| // two successors differ and two successors are the same => simplify to: If (x cmp y) |
| // determine new condition & successors |
| If::Condition cond = If::eql; |
| BlockBegin* tsux = NULL; |
| BlockBegin* fsux = NULL; |
| if (lss_sux == eql_sux) { cond = If::leq; tsux = lss_sux; fsux = gtr_sux; } |
| else if (lss_sux == gtr_sux) { cond = If::neq; tsux = lss_sux; fsux = eql_sux; } |
| else if (eql_sux == gtr_sux) { cond = If::geq; tsux = eql_sux; fsux = lss_sux; } |
| else { ShouldNotReachHere(); } |
| If* canon = new If(cmp->x(), cond, nan_sux == tsux, cmp->y(), tsux, fsux, cmp->state_before(), x->is_safepoint()); |
| if (cmp->x() == cmp->y()) { |
| do_If(canon); |
| } else { |
| if (compilation()->profile_branches()) { |
| // TODO: If profiling, leave floating point comparisons unoptimized. |
| // We currently do not support profiling of the unordered case. |
| switch(cmp->op()) { |
| case Bytecodes::_fcmpl: case Bytecodes::_fcmpg: |
| case Bytecodes::_dcmpl: case Bytecodes::_dcmpg: |
| set_canonical(x); |
| return; |
| } |
| } |
| set_bci(cmp->state_before()->bci()); |
| set_canonical(canon); |
| } |
| } |
| } else if (l->as_InstanceOf() != NULL) { |
| // NOTE: Code permanently disabled for now since it leaves the old InstanceOf |
| // instruction in the graph (it is pinned). Need to fix this at some point. |
| // It should also be left in the graph when generating a profiled method version or Goto |
| // has to know that it was an InstanceOf. |
| return; |
| // pattern: If ((obj instanceof klass) cond rc) => simplify to: IfInstanceOf or: Goto |
| InstanceOf* inst = l->as_InstanceOf(); |
| BlockBegin* is_inst_sux = x->sux_for(is_true(1, x->cond(), rc)); // successor for instanceof == 1 |
| BlockBegin* no_inst_sux = x->sux_for(is_true(0, x->cond(), rc)); // successor for instanceof == 0 |
| if (is_inst_sux == no_inst_sux && inst->is_loaded()) { |
| // both successors identical and klass is loaded => simplify to: Goto |
| set_canonical(new Goto(is_inst_sux, x->state_before(), x->is_safepoint())); |
| } else { |
| // successors differ => simplify to: IfInstanceOf |
| set_canonical(new IfInstanceOf(inst->klass(), inst->obj(), true, inst->state_before()->bci(), is_inst_sux, no_inst_sux)); |
| } |
| } |
| } else if (rt == objectNull && (l->as_NewInstance() || l->as_NewArray())) { |
| if (x->cond() == Instruction::eql) { |
| BlockBegin* sux = x->fsux(); |
| set_canonical(new Goto(sux, x->state_before(), is_safepoint(x, sux))); |
| } else { |
| assert(x->cond() == Instruction::neq, "only other valid case"); |
| BlockBegin* sux = x->tsux(); |
| set_canonical(new Goto(sux, x->state_before(), is_safepoint(x, sux))); |
| } |
| } |
| } |
| |
| |
| void Canonicalizer::do_TableSwitch(TableSwitch* x) { |
| if (x->tag()->type()->is_constant()) { |
| int v = x->tag()->type()->as_IntConstant()->value(); |
| BlockBegin* sux = x->default_sux(); |
| if (v >= x->lo_key() && v <= x->hi_key()) { |
| sux = x->sux_at(v - x->lo_key()); |
| } |
| set_canonical(new Goto(sux, x->state_before(), is_safepoint(x, sux))); |
| } else if (x->number_of_sux() == 1) { |
| // NOTE: Code permanently disabled for now since the switch statement's |
| // tag expression may produce side-effects in which case it must |
| // be executed. |
| return; |
| // simplify to Goto |
| set_canonical(new Goto(x->default_sux(), x->state_before(), x->is_safepoint())); |
| } else if (x->number_of_sux() == 2) { |
| // NOTE: Code permanently disabled for now since it produces two new nodes |
| // (Constant & If) and the Canonicalizer cannot return them correctly |
| // yet. For now we copied the corresponding code directly into the |
| // GraphBuilder (i.e., we should never reach here). |
| return; |
| // simplify to If |
| assert(x->lo_key() == x->hi_key(), "keys must be the same"); |
| Constant* key = new Constant(new IntConstant(x->lo_key())); |
| set_canonical(new If(x->tag(), If::eql, true, key, x->sux_at(0), x->default_sux(), x->state_before(), x->is_safepoint())); |
| } |
| } |
| |
| |
| void Canonicalizer::do_LookupSwitch(LookupSwitch* x) { |
| if (x->tag()->type()->is_constant()) { |
| int v = x->tag()->type()->as_IntConstant()->value(); |
| BlockBegin* sux = x->default_sux(); |
| for (int i = 0; i < x->length(); i++) { |
| if (v == x->key_at(i)) { |
| sux = x->sux_at(i); |
| } |
| } |
| set_canonical(new Goto(sux, x->state_before(), is_safepoint(x, sux))); |
| } else if (x->number_of_sux() == 1) { |
| // NOTE: Code permanently disabled for now since the switch statement's |
| // tag expression may produce side-effects in which case it must |
| // be executed. |
| return; |
| // simplify to Goto |
| set_canonical(new Goto(x->default_sux(), x->state_before(), x->is_safepoint())); |
| } else if (x->number_of_sux() == 2) { |
| // NOTE: Code permanently disabled for now since it produces two new nodes |
| // (Constant & If) and the Canonicalizer cannot return them correctly |
| // yet. For now we copied the corresponding code directly into the |
| // GraphBuilder (i.e., we should never reach here). |
| return; |
| // simplify to If |
| assert(x->length() == 1, "length must be the same"); |
| Constant* key = new Constant(new IntConstant(x->key_at(0))); |
| set_canonical(new If(x->tag(), If::eql, true, key, x->sux_at(0), x->default_sux(), x->state_before(), x->is_safepoint())); |
| } |
| } |
| |
| |
| void Canonicalizer::do_Return (Return* x) {} |
| void Canonicalizer::do_Throw (Throw* x) {} |
| void Canonicalizer::do_Base (Base* x) {} |
| void Canonicalizer::do_OsrEntry (OsrEntry* x) {} |
| void Canonicalizer::do_ExceptionObject(ExceptionObject* x) {} |
| |
| static bool match_index_and_scale(Instruction* instr, |
| Instruction** index, |
| int* log2_scale) { |
| // Skip conversion ops. This works only on 32bit because of the implicit l2i that the |
| // unsafe performs. |
| #ifndef _LP64 |
| Convert* convert = instr->as_Convert(); |
| if (convert != NULL && convert->op() == Bytecodes::_i2l) { |
| assert(convert->value()->type() == intType, "invalid input type"); |
| instr = convert->value(); |
| } |
| #endif |
| |
| ShiftOp* shift = instr->as_ShiftOp(); |
| if (shift != NULL) { |
| if (shift->op() == Bytecodes::_lshl) { |
| assert(shift->x()->type() == longType, "invalid input type"); |
| } else { |
| #ifndef _LP64 |
| if (shift->op() == Bytecodes::_ishl) { |
| assert(shift->x()->type() == intType, "invalid input type"); |
| } else { |
| return false; |
| } |
| #else |
| return false; |
| #endif |
| } |
| |
| |
| // Constant shift value? |
| Constant* con = shift->y()->as_Constant(); |
| if (con == NULL) return false; |
| // Well-known type and value? |
| IntConstant* val = con->type()->as_IntConstant(); |
| assert(val != NULL, "Should be an int constant"); |
| |
| *index = shift->x(); |
| int tmp_scale = val->value(); |
| if (tmp_scale >= 0 && tmp_scale < 4) { |
| *log2_scale = tmp_scale; |
| return true; |
| } else { |
| return false; |
| } |
| } |
| |
| ArithmeticOp* arith = instr->as_ArithmeticOp(); |
| if (arith != NULL) { |
| // See if either arg is a known constant |
| Constant* con = arith->x()->as_Constant(); |
| if (con != NULL) { |
| *index = arith->y(); |
| } else { |
| con = arith->y()->as_Constant(); |
| if (con == NULL) return false; |
| *index = arith->x(); |
| } |
| long const_value; |
| // Check for integer multiply |
| if (arith->op() == Bytecodes::_lmul) { |
| assert((*index)->type() == longType, "invalid input type"); |
| LongConstant* val = con->type()->as_LongConstant(); |
| assert(val != NULL, "expecting a long constant"); |
| const_value = val->value(); |
| } else { |
| #ifndef _LP64 |
| if (arith->op() == Bytecodes::_imul) { |
| assert((*index)->type() == intType, "invalid input type"); |
| IntConstant* val = con->type()->as_IntConstant(); |
| assert(val != NULL, "expecting an int constant"); |
| const_value = val->value(); |
| } else { |
| return false; |
| } |
| #else |
| return false; |
| #endif |
| } |
| switch (const_value) { |
| case 1: *log2_scale = 0; return true; |
| case 2: *log2_scale = 1; return true; |
| case 4: *log2_scale = 2; return true; |
| case 8: *log2_scale = 3; return true; |
| default: return false; |
| } |
| } |
| |
| // Unknown instruction sequence; don't touch it |
| return false; |
| } |
| |
| |
| static bool match(UnsafeRawOp* x, |
| Instruction** base, |
| Instruction** index, |
| int* log2_scale) { |
| ArithmeticOp* root = x->base()->as_ArithmeticOp(); |
| if (root == NULL) return false; |
| // Limit ourselves to addition for now |
| if (root->op() != Bytecodes::_ladd) return false; |
| |
| bool match_found = false; |
| // Try to find shift or scale op |
| if (match_index_and_scale(root->y(), index, log2_scale)) { |
| *base = root->x(); |
| match_found = true; |
| } else if (match_index_and_scale(root->x(), index, log2_scale)) { |
| *base = root->y(); |
| match_found = true; |
| } else if (NOT_LP64(root->y()->as_Convert() != NULL) LP64_ONLY(false)) { |
| // Skipping i2l works only on 32bit because of the implicit l2i that the unsafe performs. |
| // 64bit needs a real sign-extending conversion. |
| Convert* convert = root->y()->as_Convert(); |
| if (convert->op() == Bytecodes::_i2l) { |
| assert(convert->value()->type() == intType, "should be an int"); |
| // pick base and index, setting scale at 1 |
| *base = root->x(); |
| *index = convert->value(); |
| *log2_scale = 0; |
| match_found = true; |
| } |
| } |
| // The default solution |
| if (!match_found) { |
| *base = root->x(); |
| *index = root->y(); |
| *log2_scale = 0; |
| } |
| |
| // If the value is pinned then it will be always be computed so |
| // there's no profit to reshaping the expression. |
| return !root->is_pinned(); |
| } |
| |
| |
| void Canonicalizer::do_UnsafeRawOp(UnsafeRawOp* x) { |
| Instruction* base = NULL; |
| Instruction* index = NULL; |
| int log2_scale; |
| |
| if (match(x, &base, &index, &log2_scale)) { |
| x->set_base(base); |
| x->set_index(index); |
| x->set_log2_scale(log2_scale); |
| if (PrintUnsafeOptimization) { |
| tty->print_cr("Canonicalizer: UnsafeRawOp id %d: base = id %d, index = id %d, log2_scale = %d", |
| x->id(), x->base()->id(), x->index()->id(), x->log2_scale()); |
| } |
| } |
| } |
| |
| void Canonicalizer::do_RoundFP(RoundFP* x) {} |
| void Canonicalizer::do_UnsafeGetRaw(UnsafeGetRaw* x) { if (OptimizeUnsafes) do_UnsafeRawOp(x); } |
| void Canonicalizer::do_UnsafePutRaw(UnsafePutRaw* x) { if (OptimizeUnsafes) do_UnsafeRawOp(x); } |
| void Canonicalizer::do_UnsafeGetObject(UnsafeGetObject* x) {} |
| void Canonicalizer::do_UnsafePutObject(UnsafePutObject* x) {} |
| void Canonicalizer::do_UnsafeGetAndSetObject(UnsafeGetAndSetObject* x) {} |
| void Canonicalizer::do_UnsafePrefetchRead (UnsafePrefetchRead* x) {} |
| void Canonicalizer::do_UnsafePrefetchWrite(UnsafePrefetchWrite* x) {} |
| void Canonicalizer::do_ProfileCall(ProfileCall* x) {} |
| void Canonicalizer::do_ProfileReturnType(ProfileReturnType* x) {} |
| void Canonicalizer::do_ProfileInvoke(ProfileInvoke* x) {} |
| void Canonicalizer::do_RuntimeCall(RuntimeCall* x) {} |
| void Canonicalizer::do_RangeCheckPredicate(RangeCheckPredicate* x) {} |
| #ifdef ASSERT |
| void Canonicalizer::do_Assert(Assert* x) {} |
| #endif |
| void Canonicalizer::do_MemBar(MemBar* x) {} |
