| // Copyright 2013 the V8 project authors. All rights reserved. |
| // Redistribution and use in source and binary forms, with or without |
| // modification, are permitted provided that the following conditions are |
| // met: |
| // |
| // * Redistributions of source code must retain the above copyright |
| // notice, this list of conditions and the following disclaimer. |
| // * Redistributions in binary form must reproduce the above |
| // copyright notice, this list of conditions and the following |
| // disclaimer in the documentation and/or other materials provided |
| // with the distribution. |
| // * Neither the name of Google Inc. nor the names of its |
| // contributors may be used to endorse or promote products derived |
| // from this software without specific prior written permission. |
| // |
| // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS |
| // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT |
| // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR |
| // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT |
| // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, |
| // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT |
| // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
| // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
| // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
| // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE |
| // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| |
| #include "hydrogen-canonicalize.h" |
| |
| namespace v8 { |
| namespace internal { |
| |
| void HCanonicalizePhase::Run() { |
| const ZoneList<HBasicBlock*>* blocks(graph()->blocks()); |
| // Before removing no-op instructions, save their semantic value. |
| // We must be careful not to set the flag unnecessarily, because GVN |
| // cannot identify two instructions when their flag value differs. |
| for (int i = 0; i < blocks->length(); ++i) { |
| for (HInstructionIterator it(blocks->at(i)); !it.Done(); it.Advance()) { |
| HInstruction* instr = it.Current(); |
| if (instr->IsArithmeticBinaryOperation() && |
| instr->representation().IsInteger32() && |
| instr->HasAtLeastOneUseWithFlagAndNoneWithout( |
| HInstruction::kTruncatingToInt32)) { |
| instr->SetFlag(HInstruction::kAllUsesTruncatingToInt32); |
| } |
| } |
| } |
| // Perform actual Canonicalization pass. |
| for (int i = 0; i < blocks->length(); ++i) { |
| for (HInstructionIterator it(blocks->at(i)); !it.Done(); it.Advance()) { |
| HInstruction* instr = it.Current(); |
| HValue* value = instr->Canonicalize(); |
| if (value != instr) instr->DeleteAndReplaceWith(value); |
| } |
| } |
| } |
| |
| } } // namespace v8::internal |