src/jump-target.cc

// Copyright 2009 the V8 project authors. All rights reserved.
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#include "v8.h"

#include "codegen-inl.h"
#include "jump-target-inl.h"
#include "register-allocator-inl.h"

namespace v8 {
namespace internal {

// -------------------------------------------------------------------------
// JumpTarget implementation.

void JumpTarget::Jump() {
  DoJump();
}


void JumpTarget::Branch(Condition cc, Hint hint) {
  DoBranch(cc, hint);
}


void JumpTarget::Bind() {
  DoBind();
}


// -------------------------------------------------------------------------
// ShadowTarget implementation.

ShadowTarget::ShadowTarget(BreakTarget* shadowed) {
  ASSERT(shadowed != NULL);
  other_target_ = shadowed;

#ifdef DEBUG
  is_shadowing_ = true;
#endif
  // While shadowing this shadow target saves the state of the original.
  shadowed->CopyTo(this);

  // The original's state is reset.
  shadowed->Unuse();
  ASSERT(cgen()->has_valid_frame());
  shadowed->set_expected_height(cgen()->frame()->height());
}


void ShadowTarget::StopShadowing() {
  ASSERT(is_shadowing_);

  // The states of this target, which was shadowed, and the original
  // target, which was shadowing, are swapped.
  BreakTarget temp;
  other_target_->CopyTo(&temp);
  CopyTo(other_target_);
  temp.CopyTo(this);
  temp.Unuse();

#ifdef DEBUG
  is_shadowing_ = false;
#endif
}

} }  // namespace v8::internal