v8/src/ia32/register-allocator-ia32.cc
kmillikin@chromium.org bcab3697f6 Simplify JumpTarget::ComputeEntryFrame. Eliminate a separate pass
over the frame elements to find registers used (before allocating
undetermined elements) and another pass to set the frame's register
indices (after allocating all elements).
Review URL: http://codereview.chromium.org/114018

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@1906 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
2009-05-11 13:57:19 +00:00

137 lines
4.4 KiB
C++

// Copyright 2008 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"
namespace v8 { namespace internal {
// -------------------------------------------------------------------------
// Result implementation.
void Result::ToRegister() {
ASSERT(is_valid());
if (is_constant()) {
Result fresh = cgen_->allocator()->Allocate();
ASSERT(fresh.is_valid());
if (cgen_->IsUnsafeSmi(handle())) {
cgen_->LoadUnsafeSmi(fresh.reg(), handle());
} else {
cgen_->masm()->Set(fresh.reg(), Immediate(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 = cgen_->allocator()->Allocate(target);
ASSERT(fresh.is_valid());
if (is_register()) {
cgen_->masm()->mov(fresh.reg(), reg());
} else {
ASSERT(is_constant());
if (cgen_->IsUnsafeSmi(handle())) {
cgen_->LoadUnsafeSmi(fresh.reg(), handle());
} else {
cgen_->masm()->Set(fresh.reg(), Immediate(handle()));
}
}
*this = fresh;
} else if (is_register() && reg().is(target)) {
ASSERT(cgen_->has_valid_frame());
cgen_->frame()->Spill(target);
ASSERT(cgen_->allocator()->count(target) == 1);
}
ASSERT(is_register());
ASSERT(reg().is(target));
}
// -------------------------------------------------------------------------
// RegisterAllocator implementation.
RegisterFile RegisterAllocator::Reserved() {
RegisterFile reserved;
reserved.Use(esp);
reserved.Use(ebp);
reserved.Use(esi);
return reserved;
}
void RegisterAllocator::UnuseReserved(RegisterFile* register_file) {
register_file->ref_counts_[esp.code()] = 0;
register_file->ref_counts_[ebp.code()] = 0;
register_file->ref_counts_[esi.code()] = 0;
}
bool RegisterAllocator::IsReserved(int reg_code) {
// Test below relies on the order of register codes.
return reg_code >= esp.code() && reg_code <= esi.code();
}
void RegisterAllocator::Initialize() {
Reset();
// The following register is live on function entry, saved in the
// frame, and available for allocation during execution.
Use(edi); // JS function.
}
void RegisterAllocator::Reset() {
registers_.Reset();
// The following registers are live on function entry and reserved
// during execution.
Use(esp); // Stack pointer.
Use(ebp); // Frame pointer (caller's frame pointer on entry).
Use(esi); // Context (callee's context on entry).
}
Result RegisterAllocator::AllocateByteRegisterWithoutSpilling() {
Result result = AllocateWithoutSpilling();
// Check that the register is a byte register. If not, unuse the
// register if valid and return an invalid result.
if (result.is_valid() && !result.reg().is_byte_register()) {
result.Unuse();
return Result(cgen_);
}
return result;
}
} } // namespace v8::internal