mirror of
https://github.com/KhronosGroup/SPIRV-Tools
synced 2024-12-28 10:41:04 +00:00
78 lines
2.5 KiB
C++
78 lines
2.5 KiB
C++
// Copyright (c) 2015-2016 The Khronos Group Inc.
|
|
//
|
|
// 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 "spirv_endian.h"
|
|
|
|
#include <cstring>
|
|
|
|
enum {
|
|
I32_ENDIAN_LITTLE = 0x03020100ul,
|
|
I32_ENDIAN_BIG = 0x00010203ul,
|
|
};
|
|
|
|
// This constant value allows the detection of the host machine's endianness.
|
|
// Accessing it through the "value" member is valid due to C++11 section 3.10
|
|
// paragraph 10.
|
|
static const union {
|
|
unsigned char bytes[4];
|
|
uint32_t value;
|
|
} o32_host_order = {{0, 1, 2, 3}};
|
|
|
|
#define I32_ENDIAN_HOST (o32_host_order.value)
|
|
|
|
uint32_t spvFixWord(const uint32_t word, const spv_endianness_t endian) {
|
|
if ((SPV_ENDIANNESS_LITTLE == endian && I32_ENDIAN_HOST == I32_ENDIAN_BIG) ||
|
|
(SPV_ENDIANNESS_BIG == endian && I32_ENDIAN_HOST == I32_ENDIAN_LITTLE)) {
|
|
return (word & 0x000000ff) << 24 | (word & 0x0000ff00) << 8 |
|
|
(word & 0x00ff0000) >> 8 | (word & 0xff000000) >> 24;
|
|
}
|
|
|
|
return word;
|
|
}
|
|
|
|
uint64_t spvFixDoubleWord(const uint32_t low, const uint32_t high,
|
|
const spv_endianness_t endian) {
|
|
return (uint64_t(spvFixWord(high, endian)) << 32) | spvFixWord(low, endian);
|
|
}
|
|
|
|
spv_result_t spvBinaryEndianness(spv_const_binary binary,
|
|
spv_endianness_t* pEndian) {
|
|
if (!binary->code || !binary->wordCount) return SPV_ERROR_INVALID_BINARY;
|
|
if (!pEndian) return SPV_ERROR_INVALID_POINTER;
|
|
|
|
uint8_t bytes[4];
|
|
memcpy(bytes, binary->code, sizeof(uint32_t));
|
|
|
|
if (0x03 == bytes[0] && 0x02 == bytes[1] && 0x23 == bytes[2] &&
|
|
0x07 == bytes[3]) {
|
|
*pEndian = SPV_ENDIANNESS_LITTLE;
|
|
return SPV_SUCCESS;
|
|
}
|
|
|
|
if (0x07 == bytes[0] && 0x23 == bytes[1] && 0x02 == bytes[2] &&
|
|
0x03 == bytes[3]) {
|
|
*pEndian = SPV_ENDIANNESS_BIG;
|
|
return SPV_SUCCESS;
|
|
}
|
|
|
|
return SPV_ERROR_INVALID_BINARY;
|
|
}
|
|
|
|
bool spvIsHostEndian(spv_endianness_t endian) {
|
|
return ((SPV_ENDIANNESS_LITTLE == endian) &&
|
|
(I32_ENDIAN_LITTLE == I32_ENDIAN_HOST)) ||
|
|
((SPV_ENDIANNESS_BIG == endian) &&
|
|
(I32_ENDIAN_BIG == I32_ENDIAN_HOST));
|
|
}
|