You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.

121 lines
2.8 KiB

/*
* Copyright (C) 2011 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.
*/
#ifndef ART_COMPILER_UTILS_LABEL_H_
#define ART_COMPILER_UTILS_LABEL_H_
#include <android-base/logging.h>
#include <android-base/macros.h>
namespace art {
class Assembler;
class AssemblerBuffer;
class AssemblerFixup;
namespace arm64 {
class Arm64Assembler;
} // namespace arm64
namespace x86 {
class X86Assembler;
class NearLabel;
} // namespace x86
namespace x86_64 {
class X86_64Assembler;
class NearLabel;
} // namespace x86_64
class ExternalLabel {
public:
ExternalLabel(const char* name_in, uintptr_t address_in)
: name_(name_in), address_(address_in) {
DCHECK(name_in != nullptr);
}
const char* name() const { return name_; }
uintptr_t address() const {
return address_;
}
private:
const char* name_;
const uintptr_t address_;
};
class Label {
public:
Label() : position_(0) {}
Label(Label&& src)
: position_(src.position_) {
// We must unlink/unbind the src label when moving; if not, calling the destructor on
// the src label would fail.
src.position_ = 0;
}
~Label() {
// Assert if label is being destroyed with unresolved branches pending.
CHECK(!IsLinked());
}
// Returns the position for bound and linked labels. Cannot be used
// for unused labels.
int Position() const {
CHECK(!IsUnused());
return IsBound() ? -position_ - sizeof(void*) : position_ - sizeof(void*);
}
int LinkPosition() const {
CHECK(IsLinked());
return position_ - sizeof(void*);
}
bool IsBound() const { return position_ < 0; }
bool IsUnused() const { return position_ == 0; }
bool IsLinked() const { return position_ > 0; }
private:
int position_;
void Reinitialize() {
position_ = 0;
}
void BindTo(int position) {
CHECK(!IsBound());
position_ = -position - sizeof(void*);
CHECK(IsBound());
}
void LinkTo(int position) {
CHECK(!IsBound());
position_ = position + sizeof(void*);
CHECK(IsLinked());
}
friend class arm64::Arm64Assembler;
friend class x86::X86Assembler;
friend class x86::NearLabel;
friend class x86_64::X86_64Assembler;
friend class x86_64::NearLabel;
DISALLOW_COPY_AND_ASSIGN(Label);
};
} // namespace art
#endif // ART_COMPILER_UTILS_LABEL_H_