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Portable cpuRelax #49

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Portable cpuRelax #49

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21 changes: 20 additions & 1 deletion include/FastxParserThreadUtils.hpp
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Original file line number Diff line number Diff line change
Expand Up @@ -6,6 +6,9 @@
#include <chrono>
#include <random>
#include <pthread.h>
#if defined(__SSE2__)
#include <xmmintrin.h> // _mm_pause
#endif

// Most of this code is taken directly from https://github.com/geidav/spinlocks-bench/blob/master/os.hpp.
// However, things may be renamed, modified, or randomly mangled over time.
Expand All @@ -18,7 +21,23 @@ namespace fastx_parser {
static const size_t MAX_BACKOFF_ITERS = 1024;

ALWAYS_INLINE static void cpuRelax() {
asm("pause");
#if defined(__SSE2__) // AMD and Intel
_mm_pause();
#elif defined(__i386__) || defined(__x86_64__)
asm volatile("pause");
#elif defined(__aarch64__)
asm volatile("wfe");
#elif defined(__armel__) || defined(__ARMEL__)
asm volatile ("nop" ::: "memory");
#elif defined(__arm__) || defined(__aarch64__)
__asm__ __volatile__ ("yield" ::: "memory");
#elif defined(__ia64__) // IA64
__asm__ __volatile__ ("hint @pause");
#elif defined(__powerpc__) || defined(__ppc__) || defined(__PPC__)
__asm__ __volatile__ ("or 27,27,27" ::: "memory");
#else // everything else.
asm volatile ("nop" ::: "memory");
#endif
}

ALWAYS_INLINE void yieldSleep() {
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