/*
* Copyright (C) 2015 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include "linker/x86_64/relative_patcher_x86_64.h"
#include "compiled_method.h"
namespace art {
namespace linker {
void X86_64RelativePatcher::PatchPcRelativeReference(std::vector<uint8_t>* code,
const LinkerPatch& patch,
uint32_t patch_offset,
uint32_t target_offset) {
DCHECK_LE(patch.LiteralOffset() + 4u, code->size());
// Unsigned arithmetic with its well-defined overflow behavior is just fine here.
uint32_t displacement = target_offset - patch_offset;
displacement -= kPcDisplacement; // The base PC is at the end of the 4-byte patch.
typedef __attribute__((__aligned__(1))) int32_t unaligned_int32_t;
reinterpret_cast<unaligned_int32_t*>(&(*code)[patch.LiteralOffset()])[0] = displacement;
}
void X86_64RelativePatcher::PatchBakerReadBarrierBranch(std::vector<uint8_t>* code ATTRIBUTE_UNUSED,
const LinkerPatch& patch ATTRIBUTE_UNUSED,
uint32_t patch_offset ATTRIBUTE_UNUSED) {
LOG(FATAL) << "UNIMPLEMENTED";
}
} // namespace linker
} // namespace art