src/x64/register-allocator-x64.cc

// Copyright 2009 the V8 project authors. All rights reserved.
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// modification, are permitted provided that the following conditions are
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//
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#include "v8.h"

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

namespace v8 {
namespace internal {

// -------------------------------------------------------------------------
// Result implementation.

void Result::ToRegister() {
  ASSERT(is_valid());
  if (is_constant()) {
    Result fresh = CodeGeneratorScope::Current()->allocator()->Allocate();
    ASSERT(fresh.is_valid());
    CodeGeneratorScope::Current()->masm()->Move(fresh.reg(), handle());
    // This result becomes a copy of the fresh one.
    *this = fresh;
  }
  ASSERT(is_register());
}


void Result::ToRegister(Register target) {
  ASSERT(is_valid());
  if (!is_register() || !reg().is(target)) {
    Result fresh = CodeGeneratorScope::Current()->allocator()->Allocate(target);
    ASSERT(fresh.is_valid());
    if (is_register()) {
      CodeGeneratorScope::Current()->masm()->movq(fresh.reg(), reg());
    } else {
      ASSERT(is_constant());
      CodeGeneratorScope::Current()->masm()->Move(fresh.reg(), handle());
    }
    *this = fresh;
  } else if (is_register() && reg().is(target)) {
    ASSERT(CodeGeneratorScope::Current()->has_valid_frame());
    CodeGeneratorScope::Current()->frame()->Spill(target);
    ASSERT(CodeGeneratorScope::Current()->allocator()->count(target) == 1);
  }
  ASSERT(is_register());
  ASSERT(reg().is(target));
}


// -------------------------------------------------------------------------
// RegisterAllocator implementation.

Result RegisterAllocator::AllocateByteRegisterWithoutSpilling() {
  // This function is not used in 64-bit code.
  UNREACHABLE();
  return Result();
}


} }  // namespace v8::internal