add WEBP_DSP_INIT / WEBP_DSP_INIT_FUNC

this internalizes the init checks and provides stronger synchronization
with pthreads when available while still allowing VP8GetCPUInfo to be
modified (mostly for testing purposes). windows is left as is since a
critical section or mutex would cause a leak.

Change-Id: Ieb997e014f2805c0ae39c16f13337663521356f4
This commit is contained in:
James Zern
2018-04-16 20:19:54 -07:00
committed by Pascal Massimino
parent e122e511cf
commit d77bf512bd
15 changed files with 54 additions and 104 deletions

View File

@@ -141,6 +141,42 @@ extern "C" {
#endif
#endif
#if defined(WEBP_USE_THREAD) && !defined(_WIN32)
#include <pthread.h> // NOLINT
#define WEBP_DSP_INIT(func) do { \
static volatile VP8CPUInfo func ## _last_cpuinfo_used = \
(VP8CPUInfo)&func ## _last_cpuinfo_used; \
static pthread_mutex_t func ## _lock = PTHREAD_MUTEX_INITIALIZER; \
if (pthread_mutex_lock(&func ## _lock)) break; \
if (func ## _last_cpuinfo_used != VP8GetCPUInfo) func(); \
func ## _last_cpuinfo_used = VP8GetCPUInfo; \
(void)pthread_mutex_unlock(&func ## _lock); \
} while (0)
#else // !(defined(WEBP_USE_THREAD) && !defined(_WIN32))
#define WEBP_DSP_INIT(func) do { \
static volatile VP8CPUInfo func ## _last_cpuinfo_used = \
(VP8CPUInfo)&func ## _last_cpuinfo_used; \
if (func ## _last_cpuinfo_used == VP8GetCPUInfo) break; \
func(); \
func ## _last_cpuinfo_used = VP8GetCPUInfo; \
} while (0)
#endif // defined(WEBP_USE_THREAD) && !defined(_WIN32)
// Defines an Init + helper function that control multiple initialization of
// function pointers / tables.
/* Usage:
WEBP_DSP_INIT_FUNC(InitFunc) {
...function body
}
*/
#define WEBP_DSP_INIT_FUNC(name) \
static WEBP_TSAN_IGNORE_FUNCTION void name ## _body(void); \
WEBP_TSAN_IGNORE_FUNCTION void name(void) { \
WEBP_DSP_INIT(name ## _body); \
} \
static WEBP_TSAN_IGNORE_FUNCTION void name ## _body(void)
#define WEBP_UBSAN_IGNORE_UNDEF
#define WEBP_UBSAN_IGNORE_UNSIGNED_OVERFLOW
#if defined(__clang__) && defined(__has_attribute)
@@ -196,7 +232,7 @@ WEBP_EXTERN VP8CPUInfo VP8GetCPUInfo;
// avoiding a compiler warning.
#define WEBP_DSP_INIT_STUB(func) \
extern void func(void); \
WEBP_TSAN_IGNORE_FUNCTION void func(void) {}
void func(void) {}
//------------------------------------------------------------------------------
// Encoding