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/* Copyright 2013 Google Inc. All Rights Reserved.
Distributed under MIT license.
See file LICENSE for detail or copy at https://opensource.org/licenses/MIT
*/
/* Macros for endianness, branch prediction and unaligned loads and stores. */
#ifndef BROTLI_ENC_PORT_H_
#define BROTLI_ENC_PORT_H_
#include <assert.h>
#include <string.h> /* memcpy */
#include <brotli/port.h>
#include <brotli/types.h>
#if defined OS_LINUX || defined OS_CYGWIN
#include <endian.h>
#elif defined OS_FREEBSD
#include <machine/endian.h>
#elif defined OS_MACOSX
#include <machine/endian.h>
/* Let's try and follow the Linux convention */
#define __BYTE_ORDER BYTE_ORDER
#define __LITTLE_ENDIAN LITTLE_ENDIAN
#endif
/* define the macro BROTLI_LITTLE_ENDIAN
using the above endian definitions from endian.h if
endian.h was included */
#ifdef __BYTE_ORDER
#if __BYTE_ORDER == __LITTLE_ENDIAN
#define BROTLI_LITTLE_ENDIAN
#endif
#else
#if defined(__LITTLE_ENDIAN__)
#define BROTLI_LITTLE_ENDIAN
#endif
#endif /* __BYTE_ORDER */
#if defined(__BYTE_ORDER__) && (__BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__)
#define BROTLI_LITTLE_ENDIAN
#endif
/* Enable little-endian optimization for x64 architecture on Windows. */
#if (defined(_WIN32) || defined(_WIN64)) && defined(_M_X64)
#define BROTLI_LITTLE_ENDIAN
#endif
/* Portable handling of unaligned loads, stores, and copies.
On some platforms, like ARM, the copy functions can be more efficient
then a load and a store. */
#if defined(BROTLI_LITTLE_ENDIAN) && (\
defined(ARCH_PIII) || defined(ARCH_ATHLON) || \
defined(ARCH_K8) || defined(_ARCH_PPC))
/* x86 and x86-64 can perform unaligned loads/stores directly;
modern PowerPC hardware can also do unaligned integer loads and stores;
but note: the FPU still sends unaligned loads and stores to a trap handler!
*/
#define BROTLI_UNALIGNED_LOAD32(_p) (*(const uint32_t *)(_p))
#define BROTLI_UNALIGNED_LOAD64LE(_p) (*(const uint64_t *)(_p))
#define BROTLI_UNALIGNED_STORE64LE(_p, _val) \
(*(uint64_t *)(_p) = (_val))
#elif defined(BROTLI_LITTLE_ENDIAN) && defined(__arm__) && \
!defined(__ARM_ARCH_5__) && \
!defined(__ARM_ARCH_5T__) && \
!defined(__ARM_ARCH_5TE__) && \
!defined(__ARM_ARCH_5TEJ__) && \
!defined(__ARM_ARCH_6__) && \
!defined(__ARM_ARCH_6J__) && \
!defined(__ARM_ARCH_6K__) && \
!defined(__ARM_ARCH_6Z__) && \
!defined(__ARM_ARCH_6ZK__) && \
!defined(__ARM_ARCH_6T2__)
/* ARMv7 and newer support native unaligned accesses, but only of 16-bit
and 32-bit values (not 64-bit); older versions either raise a fatal signal,
do an unaligned read and rotate the words around a bit, or do the reads very
slowly (trip through kernel mode). */
#define BROTLI_UNALIGNED_LOAD32(_p) (*(const uint32_t *)(_p))
static BROTLI_INLINE uint64_t BROTLI_UNALIGNED_LOAD64LE(const void *p) {
uint64_t t;
memcpy(&t, p, sizeof t);
return t;
}
static BROTLI_INLINE void BROTLI_UNALIGNED_STORE64LE(void *p, uint64_t v) {
memcpy(p, &v, sizeof v);
}
#else
/* These functions are provided for architectures that don't support */
/* unaligned loads and stores. */
static BROTLI_INLINE uint32_t BROTLI_UNALIGNED_LOAD32(const void *p) {
uint32_t t;
memcpy(&t, p, sizeof t);
return t;
}
#if defined(BROTLI_LITTLE_ENDIAN)
static BROTLI_INLINE uint64_t BROTLI_UNALIGNED_LOAD64LE(const void *p) {
uint64_t t;
memcpy(&t, p, sizeof t);
return t;
}
static BROTLI_INLINE void BROTLI_UNALIGNED_STORE64LE(void *p, uint64_t v) {
memcpy(p, &v, sizeof v);
}
#else /* BROTLI_LITTLE_ENDIAN */
static BROTLI_INLINE uint64_t BROTLI_UNALIGNED_LOAD64LE(const void *p) {
const uint8_t* in = (const uint8_t*)p;
uint64_t value = (uint64_t)(in[0]);
value |= (uint64_t)(in[1]) << 8;
value |= (uint64_t)(in[2]) << 16;
value |= (uint64_t)(in[3]) << 24;
value |= (uint64_t)(in[4]) << 32;
value |= (uint64_t)(in[5]) << 40;
value |= (uint64_t)(in[6]) << 48;
value |= (uint64_t)(in[7]) << 56;
return value;
}
static BROTLI_INLINE void BROTLI_UNALIGNED_STORE64LE(void *p, uint64_t v) {
uint8_t* out = (uint8_t*)p;
out[0] = (uint8_t)v;
out[1] = (uint8_t)(v >> 8);
out[2] = (uint8_t)(v >> 16);
out[3] = (uint8_t)(v >> 24);
out[4] = (uint8_t)(v >> 32);
out[5] = (uint8_t)(v >> 40);
out[6] = (uint8_t)(v >> 48);
out[7] = (uint8_t)(v >> 56);
}
#endif /* BROTLI_LITTLE_ENDIAN */
#endif
#define TEMPLATE_(T) \
static BROTLI_INLINE T brotli_min_ ## T (T a, T b) { return a < b ? a : b; } \
static BROTLI_INLINE T brotli_max_ ## T (T a, T b) { return a > b ? a : b; }
TEMPLATE_(double) TEMPLATE_(float) TEMPLATE_(int)
TEMPLATE_(size_t) TEMPLATE_(uint32_t) TEMPLATE_(uint8_t)
#undef TEMPLATE_
#define BROTLI_MIN(T, A, B) (brotli_min_ ## T((A), (B)))
#define BROTLI_MAX(T, A, B) (brotli_max_ ## T((A), (B)))
#define BROTLI_SWAP(T, A, I, J) { \
T __brotli_swap_tmp = (A)[(I)]; \
(A)[(I)] = (A)[(J)]; \
(A)[(J)] = __brotli_swap_tmp; \
}
#define BROTLI_ENSURE_CAPACITY(M, T, A, C, R) { \
if (C < (R)) { \
size_t _new_size = (C == 0) ? (R) : C; \
T* new_array; \
while (_new_size < (R)) _new_size *= 2; \
new_array = BROTLI_ALLOC((M), T, _new_size); \
if (!BROTLI_IS_OOM(m) && C != 0) \
memcpy(new_array, A, C * sizeof(T)); \
BROTLI_FREE((M), A); \
A = new_array; \
C = _new_size; \
} \
}
#endif /* BROTLI_ENC_PORT_H_ */
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