diff options
author | Ali Ijaz Sheikh <ofrobots@google.com> | 2016-01-20 09:45:45 -0800 |
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committer | Ali Ijaz Sheikh <ofrobots@google.com> | 2016-01-21 16:53:58 -0800 |
commit | ef4170ea03a80b21b2d8a65ce432efaa370fe2fa (patch) | |
tree | e382b1b38b729cd8155b56b441c3a563914854a3 /deps/v8/src/hydrogen-uint32-analysis.cc | |
parent | 5f6dfab832979999d2f806fc1a2f1c11a25b0f35 (diff) | |
download | node-new-ef4170ea03a80b21b2d8a65ce432efaa370fe2fa.tar.gz |
deps: upgrade to V8 4.8.271.17
Pick up V8 4.8 branch-head. This branch brings in @@isConcatSpreadable,
@@toPrimitive and ToLength ES6 changes. For full details see:
http://v8project.blogspot.de/2015/11/v8-release-48.html
https://github.com/v8/v8/commit/fa163e2
Ref: https://github.com/nodejs/node/pull/4399
PR-URL: https://github.com/nodejs/node/pull/4785
Reviewed-By: bnoordhuis - Ben Noordhuis <info@bnoordhuis.nl>
Diffstat (limited to 'deps/v8/src/hydrogen-uint32-analysis.cc')
-rw-r--r-- | deps/v8/src/hydrogen-uint32-analysis.cc | 237 |
1 files changed, 0 insertions, 237 deletions
diff --git a/deps/v8/src/hydrogen-uint32-analysis.cc b/deps/v8/src/hydrogen-uint32-analysis.cc deleted file mode 100644 index c6cbc9bc35..0000000000 --- a/deps/v8/src/hydrogen-uint32-analysis.cc +++ /dev/null @@ -1,237 +0,0 @@ -// Copyright 2013 the V8 project authors. All rights reserved. -// Use of this source code is governed by a BSD-style license that can be -// found in the LICENSE file. - -#include "src/hydrogen-uint32-analysis.h" - -namespace v8 { -namespace internal { - - -static bool IsUnsignedLoad(HLoadKeyed* instr) { - switch (instr->elements_kind()) { - case UINT8_ELEMENTS: - case UINT16_ELEMENTS: - case UINT32_ELEMENTS: - case UINT8_CLAMPED_ELEMENTS: - return true; - default: - return false; - } -} - - -static bool IsUint32Operation(HValue* instr) { - return instr->IsShr() || - (instr->IsLoadKeyed() && IsUnsignedLoad(HLoadKeyed::cast(instr))) || - (instr->IsInteger32Constant() && instr->GetInteger32Constant() >= 0); -} - - -bool HUint32AnalysisPhase::IsSafeUint32Use(HValue* val, HValue* use) { - // Operations that operate on bits are safe. - if (use->IsBitwise() || use->IsShl() || use->IsSar() || use->IsShr()) { - return true; - } else if (use->IsSimulate() || use->IsArgumentsObject()) { - // Deoptimization has special support for uint32. - return true; - } else if (use->IsChange()) { - // Conversions have special support for uint32. - // This DCHECK guards that the conversion in question is actually - // implemented. Do not extend the whitelist without adding - // support to LChunkBuilder::DoChange(). - DCHECK(HChange::cast(use)->to().IsDouble() || - HChange::cast(use)->to().IsSmi() || - HChange::cast(use)->to().IsTagged()); - return true; - } else if (use->IsStoreKeyed()) { - HStoreKeyed* store = HStoreKeyed::cast(use); - if (store->is_fixed_typed_array()) { - // Storing a value into an external integer array is a bit level - // operation. - if (store->value() == val) { - // Clamping or a conversion to double should have beed inserted. - DCHECK(store->elements_kind() != UINT8_CLAMPED_ELEMENTS); - DCHECK(store->elements_kind() != FLOAT32_ELEMENTS); - DCHECK(store->elements_kind() != FLOAT64_ELEMENTS); - return true; - } - } - } else if (use->IsCompareNumericAndBranch()) { - HCompareNumericAndBranch* c = HCompareNumericAndBranch::cast(use); - return IsUint32Operation(c->left()) && IsUint32Operation(c->right()); - } - - return false; -} - - -// Iterate over all uses and verify that they are uint32 safe: either don't -// distinguish between int32 and uint32 due to their bitwise nature or -// have special support for uint32 values. -// Encountered phis are optimistically treated as safe uint32 uses, -// marked with kUint32 flag and collected in the phis_ list. A separate -// pass will be performed later by UnmarkUnsafePhis to clear kUint32 from -// phis that are not actually uint32-safe (it requires fix point iteration). -bool HUint32AnalysisPhase::Uint32UsesAreSafe(HValue* uint32val) { - bool collect_phi_uses = false; - for (HUseIterator it(uint32val->uses()); !it.Done(); it.Advance()) { - HValue* use = it.value(); - - if (use->IsPhi()) { - if (!use->CheckFlag(HInstruction::kUint32)) { - // There is a phi use of this value from a phi that is not yet - // collected in phis_ array. Separate pass is required. - collect_phi_uses = true; - } - - // Optimistically treat phis as uint32 safe. - continue; - } - - if (!IsSafeUint32Use(uint32val, use)) { - return false; - } - } - - if (collect_phi_uses) { - for (HUseIterator it(uint32val->uses()); !it.Done(); it.Advance()) { - HValue* use = it.value(); - - // There is a phi use of this value from a phi that is not yet - // collected in phis_ array. Separate pass is required. - if (use->IsPhi() && !use->CheckFlag(HInstruction::kUint32)) { - use->SetFlag(HInstruction::kUint32); - phis_.Add(HPhi::cast(use), zone()); - } - } - } - - return true; -} - - -// Check if all operands to the given phi are marked with kUint32 flag. -bool HUint32AnalysisPhase::CheckPhiOperands(HPhi* phi) { - if (!phi->CheckFlag(HInstruction::kUint32)) { - // This phi is not uint32 safe. No need to check operands. - return false; - } - - for (int j = 0; j < phi->OperandCount(); j++) { - HValue* operand = phi->OperandAt(j); - if (!operand->CheckFlag(HInstruction::kUint32)) { - // Lazily mark constants that fit into uint32 range with kUint32 flag. - if (operand->IsInteger32Constant() && - operand->GetInteger32Constant() >= 0) { - operand->SetFlag(HInstruction::kUint32); - continue; - } - - // This phi is not safe, some operands are not uint32 values. - return false; - } - } - - return true; -} - - -// Remove kUint32 flag from the phi itself and its operands. If any operand -// was a phi marked with kUint32 place it into a worklist for -// transitive clearing of kUint32 flag. -void HUint32AnalysisPhase::UnmarkPhi(HPhi* phi, ZoneList<HPhi*>* worklist) { - phi->ClearFlag(HInstruction::kUint32); - for (int j = 0; j < phi->OperandCount(); j++) { - HValue* operand = phi->OperandAt(j); - if (operand->CheckFlag(HInstruction::kUint32)) { - operand->ClearFlag(HInstruction::kUint32); - if (operand->IsPhi()) { - worklist->Add(HPhi::cast(operand), zone()); - } - } - } -} - - -void HUint32AnalysisPhase::UnmarkUnsafePhis() { - // No phis were collected. Nothing to do. - if (phis_.length() == 0) return; - - // Worklist used to transitively clear kUint32 from phis that - // are used as arguments to other phis. - ZoneList<HPhi*> worklist(phis_.length(), zone()); - - // Phi can be used as a uint32 value if and only if - // all its operands are uint32 values and all its - // uses are uint32 safe. - - // Iterate over collected phis and unmark those that - // are unsafe. When unmarking phi unmark its operands - // and add it to the worklist if it is a phi as well. - // Phis that are still marked as safe are shifted down - // so that all safe phis form a prefix of the phis_ array. - int phi_count = 0; - for (int i = 0; i < phis_.length(); i++) { - HPhi* phi = phis_[i]; - - if (CheckPhiOperands(phi) && Uint32UsesAreSafe(phi)) { - phis_[phi_count++] = phi; - } else { - UnmarkPhi(phi, &worklist); - } - } - - // Now phis array contains only those phis that have safe - // non-phi uses. Start transitively clearing kUint32 flag - // from phi operands of discovered non-safe phis until - // only safe phis are left. - while (!worklist.is_empty()) { - while (!worklist.is_empty()) { - HPhi* phi = worklist.RemoveLast(); - UnmarkPhi(phi, &worklist); - } - - // Check if any operands to safe phis were unmarked - // turning a safe phi into unsafe. The same value - // can flow into several phis. - int new_phi_count = 0; - for (int i = 0; i < phi_count; i++) { - HPhi* phi = phis_[i]; - - if (CheckPhiOperands(phi)) { - phis_[new_phi_count++] = phi; - } else { - UnmarkPhi(phi, &worklist); - } - } - phi_count = new_phi_count; - } -} - - -void HUint32AnalysisPhase::Run() { - if (!graph()->has_uint32_instructions()) return; - - ZoneList<HInstruction*>* uint32_instructions = graph()->uint32_instructions(); - for (int i = 0; i < uint32_instructions->length(); ++i) { - // Analyze instruction and mark it with kUint32 if all - // its uses are uint32 safe. - HInstruction* current = uint32_instructions->at(i); - if (current->IsLinked() && - current->representation().IsInteger32() && - Uint32UsesAreSafe(current)) { - current->SetFlag(HInstruction::kUint32); - } - } - - // Some phis might have been optimistically marked with kUint32 flag. - // Remove this flag from those phis that are unsafe and propagate - // this information transitively potentially clearing kUint32 flag - // from some non-phi operations that are used as operands to unsafe phis. - UnmarkUnsafePhis(); -} - - -} // namespace internal -} // namespace v8 |