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diff --git a/deps/v8/src/crankshaft/arm64/lithium-gap-resolver-arm64.cc b/deps/v8/src/crankshaft/arm64/lithium-gap-resolver-arm64.cc
new file mode 100644
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+++ b/deps/v8/src/crankshaft/arm64/lithium-gap-resolver-arm64.cc
@@ -0,0 +1,294 @@
+// 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/crankshaft/arm64/delayed-masm-arm64-inl.h"
+#include "src/crankshaft/arm64/lithium-codegen-arm64.h"
+#include "src/crankshaft/arm64/lithium-gap-resolver-arm64.h"
+
+namespace v8 {
+namespace internal {
+
+#define __ ACCESS_MASM((&masm_))
+
+
+void DelayedGapMasm::EndDelayedUse() {
+ DelayedMasm::EndDelayedUse();
+ if (scratch_register_used()) {
+ DCHECK(ScratchRegister().Is(root));
+ DCHECK(!pending());
+ InitializeRootRegister();
+ reset_scratch_register_used();
+ }
+}
+
+
+LGapResolver::LGapResolver(LCodeGen* owner)
+ : cgen_(owner), masm_(owner, owner->masm()), moves_(32, owner->zone()),
+ root_index_(0), in_cycle_(false), saved_destination_(NULL) {
+}
+
+
+void LGapResolver::Resolve(LParallelMove* parallel_move) {
+ DCHECK(moves_.is_empty());
+ DCHECK(!masm_.pending());
+
+ // Build up a worklist of moves.
+ BuildInitialMoveList(parallel_move);
+
+ for (int i = 0; i < moves_.length(); ++i) {
+ LMoveOperands move = moves_[i];
+
+ // Skip constants to perform them last. They don't block other moves
+ // and skipping such moves with register destinations keeps those
+ // registers free for the whole algorithm.
+ if (!move.IsEliminated() && !move.source()->IsConstantOperand()) {
+ root_index_ = i; // Any cycle is found when we reach this move again.
+ PerformMove(i);
+ if (in_cycle_) RestoreValue();
+ }
+ }
+
+ // Perform the moves with constant sources.
+ for (int i = 0; i < moves_.length(); ++i) {
+ LMoveOperands move = moves_[i];
+
+ if (!move.IsEliminated()) {
+ DCHECK(move.source()->IsConstantOperand());
+ EmitMove(i);
+ }
+ }
+
+ __ EndDelayedUse();
+
+ moves_.Rewind(0);
+}
+
+
+void LGapResolver::BuildInitialMoveList(LParallelMove* parallel_move) {
+ // Perform a linear sweep of the moves to add them to the initial list of
+ // moves to perform, ignoring any move that is redundant (the source is
+ // the same as the destination, the destination is ignored and
+ // unallocated, or the move was already eliminated).
+ const ZoneList<LMoveOperands>* moves = parallel_move->move_operands();
+ for (int i = 0; i < moves->length(); ++i) {
+ LMoveOperands move = moves->at(i);
+ if (!move.IsRedundant()) moves_.Add(move, cgen_->zone());
+ }
+ Verify();
+}
+
+
+void LGapResolver::PerformMove(int index) {
+ // Each call to this function performs a move and deletes it from the move
+ // graph. We first recursively perform any move blocking this one. We
+ // mark a move as "pending" on entry to PerformMove in order to detect
+ // cycles in the move graph.
+ LMoveOperands& current_move = moves_[index];
+
+ DCHECK(!current_move.IsPending());
+ DCHECK(!current_move.IsRedundant());
+
+ // Clear this move's destination to indicate a pending move. The actual
+ // destination is saved in a stack allocated local. Multiple moves can
+ // be pending because this function is recursive.
+ DCHECK(current_move.source() != NULL); // Otherwise it will look eliminated.
+ LOperand* destination = current_move.destination();
+ current_move.set_destination(NULL);
+
+ // Perform a depth-first traversal of the move graph to resolve
+ // dependencies. Any unperformed, unpending move with a source the same
+ // as this one's destination blocks this one so recursively perform all
+ // such moves.
+ for (int i = 0; i < moves_.length(); ++i) {
+ LMoveOperands other_move = moves_[i];
+ if (other_move.Blocks(destination) && !other_move.IsPending()) {
+ PerformMove(i);
+ // If there is a blocking, pending move it must be moves_[root_index_]
+ // and all other moves with the same source as moves_[root_index_] are
+ // sucessfully executed (because they are cycle-free) by this loop.
+ }
+ }
+
+ // We are about to resolve this move and don't need it marked as
+ // pending, so restore its destination.
+ current_move.set_destination(destination);
+
+ // The move may be blocked on a pending move, which must be the starting move.
+ // In this case, we have a cycle, and we save the source of this move to
+ // a scratch register to break it.
+ LMoveOperands other_move = moves_[root_index_];
+ if (other_move.Blocks(destination)) {
+ DCHECK(other_move.IsPending());
+ BreakCycle(index);
+ return;
+ }
+
+ // This move is no longer blocked.
+ EmitMove(index);
+}
+
+
+void LGapResolver::Verify() {
+#ifdef ENABLE_SLOW_DCHECKS
+ // No operand should be the destination for more than one move.
+ for (int i = 0; i < moves_.length(); ++i) {
+ LOperand* destination = moves_[i].destination();
+ for (int j = i + 1; j < moves_.length(); ++j) {
+ SLOW_DCHECK(!destination->Equals(moves_[j].destination()));
+ }
+ }
+#endif
+}
+
+
+void LGapResolver::BreakCycle(int index) {
+ DCHECK(moves_[index].destination()->Equals(moves_[root_index_].source()));
+ DCHECK(!in_cycle_);
+
+ // We save in a register the source of that move and we remember its
+ // destination. Then we mark this move as resolved so the cycle is
+ // broken and we can perform the other moves.
+ in_cycle_ = true;
+ LOperand* source = moves_[index].source();
+ saved_destination_ = moves_[index].destination();
+
+ if (source->IsRegister()) {
+ AcquireSavedValueRegister();
+ __ Mov(SavedValueRegister(), cgen_->ToRegister(source));
+ } else if (source->IsStackSlot()) {
+ AcquireSavedValueRegister();
+ __ Load(SavedValueRegister(), cgen_->ToMemOperand(source));
+ } else if (source->IsDoubleRegister()) {
+ __ Fmov(SavedFPValueRegister(), cgen_->ToDoubleRegister(source));
+ } else if (source->IsDoubleStackSlot()) {
+ __ Load(SavedFPValueRegister(), cgen_->ToMemOperand(source));
+ } else {
+ UNREACHABLE();
+ }
+
+ // Mark this move as resolved.
+ // This move will be actually performed by moving the saved value to this
+ // move's destination in LGapResolver::RestoreValue().
+ moves_[index].Eliminate();
+}
+
+
+void LGapResolver::RestoreValue() {
+ DCHECK(in_cycle_);
+ DCHECK(saved_destination_ != NULL);
+
+ if (saved_destination_->IsRegister()) {
+ __ Mov(cgen_->ToRegister(saved_destination_), SavedValueRegister());
+ ReleaseSavedValueRegister();
+ } else if (saved_destination_->IsStackSlot()) {
+ __ Store(SavedValueRegister(), cgen_->ToMemOperand(saved_destination_));
+ ReleaseSavedValueRegister();
+ } else if (saved_destination_->IsDoubleRegister()) {
+ __ Fmov(cgen_->ToDoubleRegister(saved_destination_),
+ SavedFPValueRegister());
+ } else if (saved_destination_->IsDoubleStackSlot()) {
+ __ Store(SavedFPValueRegister(), cgen_->ToMemOperand(saved_destination_));
+ } else {
+ UNREACHABLE();
+ }
+
+ in_cycle_ = false;
+ saved_destination_ = NULL;
+}
+
+
+void LGapResolver::EmitMove(int index) {
+ LOperand* source = moves_[index].source();
+ LOperand* destination = moves_[index].destination();
+
+ // Dispatch on the source and destination operand kinds. Not all
+ // combinations are possible.
+
+ if (source->IsRegister()) {
+ Register source_register = cgen_->ToRegister(source);
+ if (destination->IsRegister()) {
+ __ Mov(cgen_->ToRegister(destination), source_register);
+ } else {
+ DCHECK(destination->IsStackSlot());
+ __ Store(source_register, cgen_->ToMemOperand(destination));
+ }
+
+ } else if (source->IsStackSlot()) {
+ MemOperand source_operand = cgen_->ToMemOperand(source);
+ if (destination->IsRegister()) {
+ __ Load(cgen_->ToRegister(destination), source_operand);
+ } else {
+ DCHECK(destination->IsStackSlot());
+ EmitStackSlotMove(index);
+ }
+
+ } else if (source->IsConstantOperand()) {
+ LConstantOperand* constant_source = LConstantOperand::cast(source);
+ if (destination->IsRegister()) {
+ Register dst = cgen_->ToRegister(destination);
+ if (cgen_->IsSmi(constant_source)) {
+ __ Mov(dst, cgen_->ToSmi(constant_source));
+ } else if (cgen_->IsInteger32Constant(constant_source)) {
+ __ Mov(dst, cgen_->ToInteger32(constant_source));
+ } else {
+ __ LoadObject(dst, cgen_->ToHandle(constant_source));
+ }
+ } else if (destination->IsDoubleRegister()) {
+ DoubleRegister result = cgen_->ToDoubleRegister(destination);
+ __ Fmov(result, cgen_->ToDouble(constant_source));
+ } else {
+ DCHECK(destination->IsStackSlot());
+ DCHECK(!in_cycle_); // Constant moves happen after all cycles are gone.
+ if (cgen_->IsSmi(constant_source)) {
+ Smi* smi = cgen_->ToSmi(constant_source);
+ __ StoreConstant(reinterpret_cast<intptr_t>(smi),
+ cgen_->ToMemOperand(destination));
+ } else if (cgen_->IsInteger32Constant(constant_source)) {
+ __ StoreConstant(cgen_->ToInteger32(constant_source),
+ cgen_->ToMemOperand(destination));
+ } else {
+ Handle<Object> handle = cgen_->ToHandle(constant_source);
+ AllowDeferredHandleDereference smi_object_check;
+ if (handle->IsSmi()) {
+ Object* obj = *handle;
+ DCHECK(!obj->IsHeapObject());
+ __ StoreConstant(reinterpret_cast<intptr_t>(obj),
+ cgen_->ToMemOperand(destination));
+ } else {
+ AcquireSavedValueRegister();
+ __ LoadObject(SavedValueRegister(), handle);
+ __ Store(SavedValueRegister(), cgen_->ToMemOperand(destination));
+ ReleaseSavedValueRegister();
+ }
+ }
+ }
+
+ } else if (source->IsDoubleRegister()) {
+ DoubleRegister src = cgen_->ToDoubleRegister(source);
+ if (destination->IsDoubleRegister()) {
+ __ Fmov(cgen_->ToDoubleRegister(destination), src);
+ } else {
+ DCHECK(destination->IsDoubleStackSlot());
+ __ Store(src, cgen_->ToMemOperand(destination));
+ }
+
+ } else if (source->IsDoubleStackSlot()) {
+ MemOperand src = cgen_->ToMemOperand(source);
+ if (destination->IsDoubleRegister()) {
+ __ Load(cgen_->ToDoubleRegister(destination), src);
+ } else {
+ DCHECK(destination->IsDoubleStackSlot());
+ EmitStackSlotMove(index);
+ }
+
+ } else {
+ UNREACHABLE();
+ }
+
+ // The move has been emitted, we can eliminate it.
+ moves_[index].Eliminate();
+}
+
+} // namespace internal
+} // namespace v8
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