avx and avx2 detection
This doesn't do anything yet beyond print out a message in Debug mode,
but it's a start. Those messages should match the -SSE4-, -AVX-, or -AVX2- in
the Test-...-Debug-Trybots below. The Release ones are just running by accident.
So far they look right to me.
BUG=skia:
Review URL: https://codereview.chromium.org/1428153003
diff --git a/src/core/SkOpts.cpp b/src/core/SkOpts.cpp
index 1f2f567..57c387a 100644
--- a/src/core/SkOpts.cpp
+++ b/src/core/SkOpts.cpp
@@ -23,10 +23,24 @@
#if defined(SK_CPU_X86)
#if defined(SK_BUILD_FOR_WIN32)
#include <intrin.h>
- static void cpuid(uint32_t abcd[4]) { __cpuid((int*)abcd, 1); }
+ static void cpuid (uint32_t abcd[4]) { __cpuid ((int*)abcd, 1); }
+ static void cpuid7(uint32_t abcd[4]) { __cpuidex((int*)abcd, 7, 0); }
+ static uint64_t xgetbv(uint32_t xcr) { return _xgetbv(xcr); }
#else
#include <cpuid.h>
- static void cpuid(uint32_t abcd[4]) { __get_cpuid(1, abcd+0, abcd+1, abcd+2, abcd+3); }
+ #if !defined(__cpuid_count) // Old Mac Clang doesn't have this defined.
+ #define __cpuid_count(eax, ecx, a, b, c, d) \
+ __asm__("cpuid" : "=a"(a), "=b"(b), "=c"(c), "=d"(d) : "0"(eax), "2"(ecx))
+ #endif
+ static void cpuid (uint32_t abcd[4]) { __get_cpuid(1, abcd+0, abcd+1, abcd+2, abcd+3); }
+ static void cpuid7(uint32_t abcd[4]) {
+ __cpuid_count(7, 0, abcd[0], abcd[1], abcd[2], abcd[3]);
+ }
+ static uint64_t xgetbv(uint32_t xcr) {
+ uint32_t eax, edx;
+ __asm__ __volatile__ ( "xgetbv" : "=a"(eax), "=d"(edx) : "c"(xcr));
+ return (uint64_t)(edx) << 32 | eax;
+ }
#endif
#elif !defined(SK_ARM_HAS_NEON) && \
defined(SK_CPU_ARM32) && \
@@ -70,7 +84,9 @@
void Init_ssse3();
void Init_sse41();
void Init_neon();
- //TODO: _dsp2, _armv7, _armv8, _x86, _x86_64, _sse42, _avx, avx2, ... ?
+ void Init_avx() { SkDEBUGCODE( SkDebugf("avx detected\n"); ) }
+ void Init_avx2() { SkDEBUGCODE( SkDebugf("avx2 detected\n"); ) }
+ //TODO: _dsp2, _armv7, _armv8, _x86, _x86_64, _sse42, ... ?
static void init() {
// TODO: Chrome's not linking _sse* opts on iOS simulator builds. Bug or feature?
@@ -79,6 +95,18 @@
cpuid(abcd);
if (abcd[2] & (1<< 9)) { Init_ssse3(); }
if (abcd[2] & (1<<19)) { Init_sse41(); }
+
+ // AVX detection's kind of a pain. This is cribbed from Chromium.
+ if ( ( abcd[2] & (7<<26)) == (7<<26) && // Check bits 26-28 of ecx are all set,
+ (xgetbv(0) & 6 ) == 6 ){ // and check the OS supports XSAVE.
+ Init_avx();
+
+ // AVX2 additionally needs bit 5 set on ebx after calling cpuid(7).
+ uint32_t abcd7[] = {0,0,0,0};
+ cpuid7(abcd7);
+ if (abcd7[1] & (1<<5)) { Init_avx2(); }
+ }
+
#elif !defined(SK_ARM_HAS_NEON) && \
defined(SK_CPU_ARM32) && \
defined(SK_BUILD_FOR_ANDROID) && \