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#include<simdconfig.h>
#include<simdfuncs.h>
#include<stdint.h>
#ifdef _MSC_VER
#include<intrin.h>
int mmx_available(void) {
return 1;
}
/* Contrary to MSDN documentation, MMX intrinsics
* just plain don't work.
*/
void increment_mmx(float arr[4]) {
arr[0]++;
arr[1]++;
arr[2]++;
arr[3]++;
}
#elif defined(__MINGW32__)
int mmx_available(void) {
return 1;
}
/* MinGW does not seem to ship with MMX or it is broken.
*/
void increment_mmx(float arr[4]) {
arr[0]++;
arr[1]++;
arr[2]++;
arr[3]++;
}
#else
#include<mmintrin.h>
#include<cpuid.h>
#if defined(__APPLE__)
int mmx_available(void) { return 1; }
#else
int mmx_available(void) {
return __builtin_cpu_supports("mmx");
}
#endif
void increment_mmx(float arr[4]) {
/* Super ugly but we know that values in arr are always small
* enough to fit in int16;
*/
int i;
/* This is unused due to below comment about GCC 8.
__m64 packed = _mm_set_pi16(arr[3], arr[2], arr[1], arr[0]);
__m64 incr = _mm_set1_pi16(1);
__m64 result = _mm_add_pi16(packed, incr);
int64_t unpacker = (int64_t)(result);
*/
/* The above should be
* int64_t unpacker = _m_to_int64(result);
* but it does not exist on 32 bit platforms for some reason.
*/
_mm_empty();
for(i=0; i<4; i++) {
/* This fails on GCC 8 when optimizations are enabled.
* Disable it. Patches welcome to fix this.
arr[i] = (float)(unpacker & ((1<<16)-1));
unpacker >>= 16;
*/
arr[i] += 1.0f;
}
}
#endif
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