pandory500/SDL-mirror
2
0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

cpuinfo: Added some internal SIMD-aligned allocation functions.

Browse source 
Fixes Bugzilla #4150 (sort of).

--HG--
extra : rebase_source : af4df4fe459ce28889fb225717c418e6c1ef9ae4
extra : histedit_source : aafd7e609c08ea908255e205d23e3efdc88837a1
This commit is contained in:
Ryan C. Gordon 2018-05-21 11:34:57 -04:00
parent bebfd14c33
commit fbfce09170
3 changed files with 140 additions and 1 deletions
Download patch file Download diff file Expand all files Collapse all files

52
src/cpuinfo/SDL_cpuinfo.c
View file

@ -38,6 +38,7 @@
/* CPU feature detection for SDL */
#include "SDL_cpuinfo.h"
#include "SDL_assert.h"
#ifdef HAVE_SYSCONF
#include <unistd.h>
@ -571,6 +572,7 @@ SDL_GetCPUCacheLineSize(void)
}
static Uint32 SDL_CPUFeatures = 0xFFFFFFFF;
static Uint32 SDL_SIMDAlignment = 0xFFFFFFFF;
static Uint32
SDL_GetCPUFeatures(void)
@ -578,41 +580,53 @@ SDL_GetCPUFeatures(void)
if (SDL_CPUFeatures == 0xFFFFFFFF) {
CPU_calcCPUIDFeatures();
SDL_CPUFeatures = 0;
SDL_SIMDAlignment = 4; /* a good safe base value */
if (CPU_haveRDTSC()) {
SDL_CPUFeatures |= CPU_HAS_RDTSC;
}
if (CPU_haveAltiVec()) {
SDL_CPUFeatures |= CPU_HAS_ALTIVEC;
SDL_SIMDAlignment = SDL_max(SDL_SIMDAlignment, 16);
}
if (CPU_haveMMX()) {
SDL_CPUFeatures |= CPU_HAS_MMX;
SDL_SIMDAlignment = SDL_max(SDL_SIMDAlignment, 8);
}
if (CPU_have3DNow()) {
SDL_CPUFeatures |= CPU_HAS_3DNOW;
SDL_SIMDAlignment = SDL_max(SDL_SIMDAlignment, 8);
}
if (CPU_haveSSE()) {
SDL_CPUFeatures |= CPU_HAS_SSE;
SDL_SIMDAlignment = SDL_max(SDL_SIMDAlignment, 16);
}
if (CPU_haveSSE2()) {
SDL_CPUFeatures |= CPU_HAS_SSE2;
SDL_SIMDAlignment = SDL_max(SDL_SIMDAlignment, 16);
}
if (CPU_haveSSE3()) {
SDL_CPUFeatures |= CPU_HAS_SSE3;
SDL_SIMDAlignment = SDL_max(SDL_SIMDAlignment, 16);
}
if (CPU_haveSSE41()) {
SDL_CPUFeatures |= CPU_HAS_SSE41;
SDL_SIMDAlignment = SDL_max(SDL_SIMDAlignment, 16);
}
if (CPU_haveSSE42()) {
SDL_CPUFeatures |= CPU_HAS_SSE42;
SDL_SIMDAlignment = SDL_max(SDL_SIMDAlignment, 16);
}
if (CPU_haveAVX()) {
SDL_CPUFeatures |= CPU_HAS_AVX;
SDL_SIMDAlignment = SDL_max(SDL_SIMDAlignment, 32);
}
if (CPU_haveAVX2()) {
SDL_CPUFeatures |= CPU_HAS_AVX2;
SDL_SIMDAlignment = SDL_max(SDL_SIMDAlignment, 32);
}
if (CPU_haveNEON()) {
SDL_CPUFeatures |= CPU_HAS_NEON;
SDL_SIMDAlignment = SDL_max(SDL_SIMDAlignment, 16);
}
}
return SDL_CPUFeatures;
@ -745,6 +759,44 @@ SDL_GetSystemRAM(void)
}
size_t
SDL_SIMDGetAlignment(void)
{
if (SDL_SIMDAlignment == 0xFFFFFFFF) {
SDL_GetCPUFeatures(); /* make sure this has been calculated */
}
SDL_assert(SDL_SIMDAlignment != 0);
return SDL_SIMDAlignment;
}
void *
SDL_SIMDAlloc(const size_t len)
{
const size_t alignment = SDL_SIMDGetAlignment();
const size_t padding = alignment - (len % alignment);
const size_t padded = (padding != alignment) ? (len + padding) : len;
Uint8 *retval = NULL;
Uint8 *ptr = (Uint8 *) SDL_malloc(padded + alignment + sizeof (void *));
if (ptr) {
/* store the actual malloc pointer right before our aligned pointer. */
retval = ptr + sizeof (void *);
retval += alignment - (((size_t) retval) % alignment);
*(((void **) retval) - 1) = ptr;
}
return retval;
}
void
SDL_SIMDFree(void *ptr)
{
if (ptr) {
void **realptr = (void **) ptr;
realptr--;
SDL_free(*(((void **) ptr) - 1));
}
}
#ifdef TEST_MAIN
#include <stdio.h>