ARM64: Regenerate instead of spilling and restoring cheap lithium instructions.

src/lithium.cc

 // Copyright 2012 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 "v8.h"
 #include "lithium.h"
 #include "scopes.h"
 #include "serialize.h"
 
 #if V8_TARGET_ARCH_IA32
@@ skipping 116 matching lines @@
 }
 
 
 void LOperand::TearDownCaches() {
 #define LITHIUM_OPERAND_TEARDOWN(name, type, number) L##name::TearDownCache();
   LITHIUM_OPERAND_LIST(LITHIUM_OPERAND_TEARDOWN)
 #undef LITHIUM_OPERAND_TEARDOWN
 }
 
 
+bool LMoveOperands::UsesRegeneration() const {
+  bool prefer_regen =
+      (source_->parent_linstr() == destination_->parent_linstr()) &&
+      (destination_->parent_linstr() != NULL) &&
+      destination_->parent_linstr()->PreferRegenerateToSpill();
+  bool one_is_mem = source_->IsInMemory() || destination_->IsInMemory();
+  bool one_is_reg = source_->IsInRegister() || destination_->IsInRegister();
+  return prefer_regen && one_is_mem && one_is_reg;
+}
+
+
 bool LParallelMove::IsRedundant() const {
   for (int i = 0; i < move_operands_.length(); ++i) {
     if (!move_operands_[i].IsRedundant()) return false;
   }
   return true;
 }
 
 
 void LParallelMove::PrintDataTo(StringStream* stream) const {
   bool first = true;
@@ skipping 466 matching lines @@
 
 
 LPhase::~LPhase() {
   if (ShouldProduceTraceOutput()) {
     isolate()->GetHTracer()->TraceLithium(name(), chunk_);
   }
 }
 
 
 } }  // namespace v8::internal