Remove some dead code.

src/register-allocator.cc

-// Copyright 2009 the V8 project authors. All rights reserved.
-// Redistribution and use in source and binary forms, with or without
-// modification, are permitted provided that the following conditions are
-// met:
-//
-//     * Redistributions of source code must retain the above copyright
-//       notice, this list of conditions and the following disclaimer.
-//     * Redistributions in binary form must reproduce the above
-//       copyright notice, this list of conditions and the following
-//       disclaimer in the documentation and/or other materials provided
-//       with the distribution.
-//     * Neither the name of Google Inc. nor the names of its
-//       contributors may be used to endorse or promote products derived
-//       from this software without specific prior written permission.
-//
-// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
-// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
-// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
-// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
-// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
-// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
-// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
-// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
-// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
-// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
-// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
-
-#include "v8.h"
-
-#include "codegen-inl.h"
-#include "register-allocator-inl.h"
-#include "virtual-frame-inl.h"
-
-namespace v8 {
-namespace internal {
-
-// -------------------------------------------------------------------------
-// Result implementation.
-
-
-Result::Result(Register reg, TypeInfo info) {
-  ASSERT(reg.is_valid() && !RegisterAllocator::IsReserved(reg));
-  CodeGeneratorScope::Current(Isolate::Current())->allocator()->Use(reg);
-  value_ = TypeField::encode(REGISTER)
-      | TypeInfoField::encode(info.ToInt())
-      | DataField::encode(reg.code_);
-}
-
-
-// -------------------------------------------------------------------------
-// RegisterAllocator implementation.
-
-
-Result RegisterAllocator::AllocateWithoutSpilling() {
-  // Return the first free register, if any.
-  int num = registers_.ScanForFreeRegister();
-  if (num == RegisterAllocator::kInvalidRegister) {
-    return Result();
-  }
-  return Result(RegisterAllocator::ToRegister(num));
-}
-
-
-Result RegisterAllocator::Allocate() {
-  Result result = AllocateWithoutSpilling();
-  if (!result.is_valid()) {
-    // Ask the current frame to spill a register.
-    ASSERT(cgen_->has_valid_frame());
-    Register free_reg = cgen_->frame()->SpillAnyRegister();
-    if (free_reg.is_valid()) {
-      ASSERT(!is_used(free_reg));
-      return Result(free_reg);
-    }
-  }
-  return result;
-}
-
-
-Result RegisterAllocator::Allocate(Register target) {
-  // If the target is not referenced, it can simply be allocated.
-  if (!is_used(RegisterAllocator::ToNumber(target))) {
-    return Result(target);
-  }
-  // If the target is only referenced in the frame, it can be spilled and
-  // then allocated.
-  ASSERT(cgen_->has_valid_frame());
-  if (cgen_->frame()->is_used(RegisterAllocator::ToNumber(target)) &&
-      count(target) == 1)  {
-    cgen_->frame()->Spill(target);
-    ASSERT(!is_used(RegisterAllocator::ToNumber(target)));
-    return Result(target);
-  }
-  // Otherwise (if it's referenced outside the frame) we cannot allocate it.
-  return Result();
-}
-
-
-} }  // namespace v8::internal