xemu/disas/libvixl/code-buffer.h
Peter Maydell 6aea44fc2b disas/libvixl: Update to libvixl 1.6
Update our copy of libvixl to upstream 1.6. There are no
changes of any particular interest to QEMU, so this is simply
keeping up with current upstream.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 1412091418-25744-1-git-send-email-peter.maydell@linaro.org
2014-10-24 12:19:11 +01:00

114 lines
3.7 KiB
C++

// Copyright 2014, ARM Limited
// 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 ARM Limited 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 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.
#ifndef VIXL_CODE_BUFFER_H
#define VIXL_CODE_BUFFER_H
#include <string.h>
#include "globals.h"
namespace vixl {
class CodeBuffer {
public:
explicit CodeBuffer(size_t capacity = 4 * KBytes);
CodeBuffer(void* buffer, size_t capacity);
~CodeBuffer();
void Reset();
ptrdiff_t OffsetFrom(ptrdiff_t offset) const {
ptrdiff_t cursor_offset = cursor_ - buffer_;
VIXL_ASSERT((offset >= 0) && (offset <= cursor_offset));
return cursor_offset - offset;
}
ptrdiff_t CursorOffset() const {
return OffsetFrom(0);
}
template <typename T>
T GetOffsetAddress(ptrdiff_t offset) const {
VIXL_ASSERT((offset >= 0) && (offset <= (cursor_ - buffer_)));
return reinterpret_cast<T>(buffer_ + offset);
}
size_t RemainingBytes() const {
VIXL_ASSERT((cursor_ >= buffer_) && (cursor_ <= (buffer_ + capacity_)));
return (buffer_ + capacity_) - cursor_;
}
// A code buffer can emit:
// * 32-bit data: instruction and constant.
// * 64-bit data: constant.
// * string: debug info.
void Emit32(uint32_t data) { Emit(data); }
void Emit64(uint64_t data) { Emit(data); }
void EmitString(const char* string);
// Align to kInstructionSize.
void Align();
size_t capacity() const { return capacity_; }
bool IsManaged() const { return managed_; }
void Grow(size_t new_capacity);
bool IsDirty() const { return dirty_; }
void SetClean() { dirty_ = false; }
private:
template <typename T>
void Emit(T value) {
VIXL_ASSERT(RemainingBytes() >= sizeof(value));
dirty_ = true;
memcpy(cursor_, &value, sizeof(value));
cursor_ += sizeof(value);
}
// Backing store of the buffer.
byte* buffer_;
// If true the backing store is allocated and deallocated by the buffer. The
// backing store can then grow on demand. If false the backing store is
// provided by the user and cannot be resized internally.
bool managed_;
// Pointer to the next location to be written.
byte* cursor_;
// True if there has been any write since the buffer was created or cleaned.
bool dirty_;
// Capacity in bytes of the backing store.
size_t capacity_;
};
} // namespace vixl
#endif // VIXL_CODE_BUFFER_H