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author | 2016-06-03 03:33:22 +0000 | |
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committer | 2016-06-03 03:33:23 +0000 | |
commit | da27230f80795d0028333713f036d44c53cb0e68 (patch) | |
tree | b3d379eaf000adf72b36cb01cdf4d79c3e3f064c /qemu/disas/libvixl/vixl/code-buffer.h | |
parent | 0e68cb048bb8aadb14675f5d4286d8ab2fc35449 (diff) | |
parent | 437fd90c0250dee670290f9b714253671a990160 (diff) |
Merge "These changes are the raw update to qemu-2.6."
Diffstat (limited to 'qemu/disas/libvixl/vixl/code-buffer.h')
-rw-r--r-- | qemu/disas/libvixl/vixl/code-buffer.h | 113 |
1 files changed, 113 insertions, 0 deletions
diff --git a/qemu/disas/libvixl/vixl/code-buffer.h b/qemu/disas/libvixl/vixl/code-buffer.h new file mode 100644 index 000000000..f93ebb6b8 --- /dev/null +++ b/qemu/disas/libvixl/vixl/code-buffer.h @@ -0,0 +1,113 @@ +// 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 "vixl/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 + |