| Index: src/arm/lithium-gap-resolver-arm.cc
|
| diff --git a/src/arm/lithium-gap-resolver-arm.cc b/src/arm/lithium-gap-resolver-arm.cc
|
| deleted file mode 100644
|
| index e1bd47b2ec034fed49e4dc7f5b061056029a703e..0000000000000000000000000000000000000000
|
| --- a/src/arm/lithium-gap-resolver-arm.cc
|
| +++ /dev/null
|
| @@ -1,301 +0,0 @@
|
| -// 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 "src/arm/lithium-codegen-arm.h"
|
| -#include "src/arm/lithium-gap-resolver-arm.h"
|
| -
|
| -namespace v8 {
|
| -namespace internal {
|
| -
|
| -// We use the root register to spill a value while breaking a cycle in parallel
|
| -// moves. We don't need access to roots while resolving the move list and using
|
| -// the root register has two advantages:
|
| -// - It is not in crankshaft allocatable registers list, so it can't interfere
|
| -// with any of the moves we are resolving.
|
| -// - We don't need to push it on the stack, as we can reload it with its value
|
| -// once we have resolved a cycle.
|
| -#define kSavedValueRegister kRootRegister
|
| -
|
| -
|
| -LGapResolver::LGapResolver(LCodeGen* owner)
|
| - : cgen_(owner), moves_(32, owner->zone()), root_index_(0), in_cycle_(false),
|
| - saved_destination_(NULL), need_to_restore_root_(false) { }
|
| -
|
| -
|
| -#define __ ACCESS_MASM(cgen_->masm())
|
| -
|
| -
|
| -void LGapResolver::Resolve(LParallelMove* parallel_move) {
|
| - DCHECK(moves_.is_empty());
|
| - // 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 by reaching this move again.
|
| - PerformMove(i);
|
| - if (in_cycle_) {
|
| - RestoreValue();
|
| - }
|
| - }
|
| - }
|
| -
|
| - // Perform the moves with constant sources.
|
| - for (int i = 0; i < moves_.length(); ++i) {
|
| - if (!moves_[i].IsEliminated()) {
|
| - DCHECK(moves_[i].source()->IsConstantOperand());
|
| - EmitMove(i);
|
| - }
|
| - }
|
| -
|
| - if (need_to_restore_root_) {
|
| - DCHECK(kSavedValueRegister.is(kRootRegister));
|
| - __ InitializeRootRegister();
|
| - need_to_restore_root_ = false;
|
| - }
|
| -
|
| - 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.
|
| -
|
| - // We can only find a cycle, when doing a depth-first traversal of moves,
|
| - // be encountering the starting move again. So by spilling the source of
|
| - // the starting move, we break the cycle. All moves are then unblocked,
|
| - // and the starting move is completed by writing the spilled value to
|
| - // its destination. All other moves from the spilled source have been
|
| - // completed prior to breaking the cycle.
|
| - // An additional complication is that moves to MemOperands with large
|
| - // offsets (more than 1K or 4K) require us to spill this spilled value to
|
| - // the stack, to free up the register.
|
| - DCHECK(!moves_[index].IsPending());
|
| - DCHECK(!moves_[index].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(moves_[index].source() != NULL); // Or else it will look eliminated.
|
| - LOperand* destination = moves_[index].destination();
|
| - moves_[index].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.
|
| - moves_[index].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) {
|
| - // 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.
|
| - DCHECK(moves_[index].destination()->Equals(moves_[root_index_].source()));
|
| - DCHECK(!in_cycle_);
|
| - in_cycle_ = true;
|
| - LOperand* source = moves_[index].source();
|
| - saved_destination_ = moves_[index].destination();
|
| - if (source->IsRegister()) {
|
| - need_to_restore_root_ = true;
|
| - __ mov(kSavedValueRegister, cgen_->ToRegister(source));
|
| - } else if (source->IsStackSlot()) {
|
| - need_to_restore_root_ = true;
|
| - __ ldr(kSavedValueRegister, cgen_->ToMemOperand(source));
|
| - } else if (source->IsDoubleRegister()) {
|
| - __ vmov(kScratchDoubleReg, cgen_->ToDoubleRegister(source));
|
| - } else if (source->IsDoubleStackSlot()) {
|
| - __ vldr(kScratchDoubleReg, cgen_->ToMemOperand(source));
|
| - } else {
|
| - UNREACHABLE();
|
| - }
|
| - // This move will be done by restoring the saved value to the destination.
|
| - moves_[index].Eliminate();
|
| -}
|
| -
|
| -
|
| -void LGapResolver::RestoreValue() {
|
| - DCHECK(in_cycle_);
|
| - DCHECK(saved_destination_ != NULL);
|
| -
|
| - if (saved_destination_->IsRegister()) {
|
| - __ mov(cgen_->ToRegister(saved_destination_), kSavedValueRegister);
|
| - } else if (saved_destination_->IsStackSlot()) {
|
| - __ str(kSavedValueRegister, cgen_->ToMemOperand(saved_destination_));
|
| - } else if (saved_destination_->IsDoubleRegister()) {
|
| - __ vmov(cgen_->ToDoubleRegister(saved_destination_), kScratchDoubleReg);
|
| - } else if (saved_destination_->IsDoubleStackSlot()) {
|
| - __ vstr(kScratchDoubleReg, 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());
|
| - __ str(source_register, cgen_->ToMemOperand(destination));
|
| - }
|
| - } else if (source->IsStackSlot()) {
|
| - MemOperand source_operand = cgen_->ToMemOperand(source);
|
| - if (destination->IsRegister()) {
|
| - __ ldr(cgen_->ToRegister(destination), source_operand);
|
| - } else {
|
| - DCHECK(destination->IsStackSlot());
|
| - MemOperand destination_operand = cgen_->ToMemOperand(destination);
|
| - if (!destination_operand.OffsetIsUint12Encodable()) {
|
| - // ip is overwritten while saving the value to the destination.
|
| - // Therefore we can't use ip. It is OK if the read from the source
|
| - // destroys ip, since that happens before the value is read.
|
| - __ vldr(kScratchDoubleReg.low(), source_operand);
|
| - __ vstr(kScratchDoubleReg.low(), destination_operand);
|
| - } else {
|
| - __ ldr(ip, source_operand);
|
| - __ str(ip, destination_operand);
|
| - }
|
| - }
|
| -
|
| - } else if (source->IsConstantOperand()) {
|
| - LConstantOperand* constant_source = LConstantOperand::cast(source);
|
| - if (destination->IsRegister()) {
|
| - Register dst = cgen_->ToRegister(destination);
|
| - Representation r = cgen_->IsSmi(constant_source)
|
| - ? Representation::Smi() : Representation::Integer32();
|
| - if (cgen_->IsInteger32(constant_source)) {
|
| - __ mov(dst, Operand(cgen_->ToRepresentation(constant_source, r)));
|
| - } else {
|
| - __ Move(dst, cgen_->ToHandle(constant_source));
|
| - }
|
| - } else if (destination->IsDoubleRegister()) {
|
| - DwVfpRegister result = cgen_->ToDoubleRegister(destination);
|
| - double v = cgen_->ToDouble(constant_source);
|
| - __ Vmov(result, v, ip);
|
| - } else {
|
| - DCHECK(destination->IsStackSlot());
|
| - DCHECK(!in_cycle_); // Constant moves happen after all cycles are gone.
|
| - need_to_restore_root_ = true;
|
| - Representation r = cgen_->IsSmi(constant_source)
|
| - ? Representation::Smi() : Representation::Integer32();
|
| - if (cgen_->IsInteger32(constant_source)) {
|
| - __ mov(kSavedValueRegister,
|
| - Operand(cgen_->ToRepresentation(constant_source, r)));
|
| - } else {
|
| - __ Move(kSavedValueRegister, cgen_->ToHandle(constant_source));
|
| - }
|
| - __ str(kSavedValueRegister, cgen_->ToMemOperand(destination));
|
| - }
|
| -
|
| - } else if (source->IsDoubleRegister()) {
|
| - DwVfpRegister source_register = cgen_->ToDoubleRegister(source);
|
| - if (destination->IsDoubleRegister()) {
|
| - __ vmov(cgen_->ToDoubleRegister(destination), source_register);
|
| - } else {
|
| - DCHECK(destination->IsDoubleStackSlot());
|
| - __ vstr(source_register, cgen_->ToMemOperand(destination));
|
| - }
|
| -
|
| - } else if (source->IsDoubleStackSlot()) {
|
| - MemOperand source_operand = cgen_->ToMemOperand(source);
|
| - if (destination->IsDoubleRegister()) {
|
| - __ vldr(cgen_->ToDoubleRegister(destination), source_operand);
|
| - } else {
|
| - DCHECK(destination->IsDoubleStackSlot());
|
| - MemOperand destination_operand = cgen_->ToMemOperand(destination);
|
| - if (in_cycle_) {
|
| - // kScratchDoubleReg was used to break the cycle.
|
| - __ vpush(kScratchDoubleReg);
|
| - __ vldr(kScratchDoubleReg, source_operand);
|
| - __ vstr(kScratchDoubleReg, destination_operand);
|
| - __ vpop(kScratchDoubleReg);
|
| - } else {
|
| - __ vldr(kScratchDoubleReg, source_operand);
|
| - __ vstr(kScratchDoubleReg, destination_operand);
|
| - }
|
| - }
|
| - } else {
|
| - UNREACHABLE();
|
| - }
|
| -
|
| - moves_[index].Eliminate();
|
| -}
|
| -
|
| -
|
| -#undef __
|
| -
|
| -} // namespace internal
|
| -} // namespace v8
|
|
|