mirror of
https://github.com/FFmpeg/FFmpeg.git
synced 2024-12-18 03:19:31 +02:00
a665704402
* commit '4d6ee0725553a43ba88d6f8327ebcf8f1c5ae8d4':
libavutil: x86: Add AVX2 capable CPU detection.
Conflicts:
libavutil/cpu.c
libavutil/cpu.h
libavutil/x86/cpu.c
See: 865b70bc5d
Merged-by: Michael Niedermayer <michaelni@gmx.at>
211 lines
7.1 KiB
C
211 lines
7.1 KiB
C
/*
|
|
* CPU detection code, extracted from mmx.h
|
|
* (c)1997-99 by H. Dietz and R. Fisher
|
|
* Converted to C and improved by Fabrice Bellard.
|
|
*
|
|
* This file is part of FFmpeg.
|
|
*
|
|
* FFmpeg is free software; you can redistribute it and/or
|
|
* modify it under the terms of the GNU Lesser General Public
|
|
* License as published by the Free Software Foundation; either
|
|
* version 2.1 of the License, or (at your option) any later version.
|
|
*
|
|
* FFmpeg is distributed in the hope that it will be useful,
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
|
* Lesser General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU Lesser General Public
|
|
* License along with FFmpeg; if not, write to the Free Software
|
|
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
|
|
*/
|
|
|
|
#include <stdlib.h>
|
|
#include <string.h>
|
|
|
|
#include "libavutil/x86/asm.h"
|
|
#include "libavutil/x86/cpu.h"
|
|
#include "libavutil/cpu.h"
|
|
#include "libavutil/cpu_internal.h"
|
|
|
|
#if HAVE_YASM
|
|
|
|
#define cpuid(index, eax, ebx, ecx, edx) \
|
|
ff_cpu_cpuid(index, &eax, &ebx, &ecx, &edx)
|
|
|
|
#define xgetbv(index, eax, edx) \
|
|
ff_cpu_xgetbv(index, &eax, &edx)
|
|
|
|
#elif HAVE_INLINE_ASM
|
|
|
|
/* ebx saving is necessary for PIC. gcc seems unable to see it alone */
|
|
#define cpuid(index, eax, ebx, ecx, edx) \
|
|
__asm__ volatile ( \
|
|
"mov %%"REG_b", %%"REG_S" \n\t" \
|
|
"cpuid \n\t" \
|
|
"xchg %%"REG_b", %%"REG_S \
|
|
: "=a" (eax), "=S" (ebx), "=c" (ecx), "=d" (edx) \
|
|
: "0" (index))
|
|
|
|
#define xgetbv(index, eax, edx) \
|
|
__asm__ (".byte 0x0f, 0x01, 0xd0" : "=a"(eax), "=d"(edx) : "c" (index))
|
|
|
|
#define get_eflags(x) \
|
|
__asm__ volatile ("pushfl \n" \
|
|
"pop %0 \n" \
|
|
: "=r"(x))
|
|
|
|
#define set_eflags(x) \
|
|
__asm__ volatile ("push %0 \n" \
|
|
"popfl \n" \
|
|
:: "r"(x))
|
|
|
|
#endif /* HAVE_INLINE_ASM */
|
|
|
|
#if ARCH_X86_64
|
|
|
|
#define cpuid_test() 1
|
|
|
|
#elif HAVE_YASM
|
|
|
|
#define cpuid_test ff_cpu_cpuid_test
|
|
|
|
#elif HAVE_INLINE_ASM
|
|
|
|
static int cpuid_test(void)
|
|
{
|
|
x86_reg a, c;
|
|
|
|
/* Check if CPUID is supported by attempting to toggle the ID bit in
|
|
* the EFLAGS register. */
|
|
get_eflags(a);
|
|
set_eflags(a ^ 0x200000);
|
|
get_eflags(c);
|
|
|
|
return a != c;
|
|
}
|
|
#endif
|
|
|
|
/* Function to test if multimedia instructions are supported... */
|
|
int ff_get_cpu_flags_x86(void)
|
|
{
|
|
int rval = 0;
|
|
|
|
#ifdef cpuid
|
|
|
|
int eax, ebx, ecx, edx;
|
|
int max_std_level, max_ext_level, std_caps = 0, ext_caps = 0;
|
|
int family = 0, model = 0;
|
|
union { int i[3]; char c[12]; } vendor;
|
|
|
|
if (!cpuid_test())
|
|
return 0; /* CPUID not supported */
|
|
|
|
cpuid(0, max_std_level, vendor.i[0], vendor.i[2], vendor.i[1]);
|
|
|
|
if (max_std_level >= 1) {
|
|
cpuid(1, eax, ebx, ecx, std_caps);
|
|
family = ((eax >> 8) & 0xf) + ((eax >> 20) & 0xff);
|
|
model = ((eax >> 4) & 0xf) + ((eax >> 12) & 0xf0);
|
|
if (std_caps & (1 << 15))
|
|
rval |= AV_CPU_FLAG_CMOV;
|
|
if (std_caps & (1 << 23))
|
|
rval |= AV_CPU_FLAG_MMX;
|
|
if (std_caps & (1 << 25))
|
|
rval |= AV_CPU_FLAG_MMXEXT;
|
|
#if HAVE_SSE
|
|
if (std_caps & (1 << 25))
|
|
rval |= AV_CPU_FLAG_SSE;
|
|
if (std_caps & (1 << 26))
|
|
rval |= AV_CPU_FLAG_SSE2;
|
|
if (ecx & 1)
|
|
rval |= AV_CPU_FLAG_SSE3;
|
|
if (ecx & 0x00000200 )
|
|
rval |= AV_CPU_FLAG_SSSE3;
|
|
if (ecx & 0x00080000 )
|
|
rval |= AV_CPU_FLAG_SSE4;
|
|
if (ecx & 0x00100000 )
|
|
rval |= AV_CPU_FLAG_SSE42;
|
|
#if HAVE_AVX
|
|
/* Check OXSAVE and AVX bits */
|
|
if ((ecx & 0x18000000) == 0x18000000) {
|
|
/* Check for OS support */
|
|
xgetbv(0, eax, edx);
|
|
if ((eax & 0x6) == 0x6)
|
|
rval |= AV_CPU_FLAG_AVX;
|
|
}
|
|
#if HAVE_AVX2
|
|
if (max_std_level >= 7) {
|
|
cpuid(7, eax, ebx, ecx, edx);
|
|
if (ebx&0x00000020)
|
|
rval |= AV_CPU_FLAG_AVX2;
|
|
/* TODO: BMI1/2 */
|
|
}
|
|
#endif /* HAVE_AVX2 */
|
|
#endif /* HAVE_AVX */
|
|
#endif /* HAVE_SSE */
|
|
}
|
|
|
|
cpuid(0x80000000, max_ext_level, ebx, ecx, edx);
|
|
|
|
if (max_ext_level >= 0x80000001) {
|
|
cpuid(0x80000001, eax, ebx, ecx, ext_caps);
|
|
if (ext_caps & (1U << 31))
|
|
rval |= AV_CPU_FLAG_3DNOW;
|
|
if (ext_caps & (1 << 30))
|
|
rval |= AV_CPU_FLAG_3DNOWEXT;
|
|
if (ext_caps & (1 << 23))
|
|
rval |= AV_CPU_FLAG_MMX;
|
|
if (ext_caps & (1 << 22))
|
|
rval |= AV_CPU_FLAG_MMXEXT;
|
|
|
|
/* Allow for selectively disabling SSE2 functions on AMD processors
|
|
with SSE2 support but not SSE4a. This includes Athlon64, some
|
|
Opteron, and some Sempron processors. MMX, SSE, or 3DNow! are faster
|
|
than SSE2 often enough to utilize this special-case flag.
|
|
AV_CPU_FLAG_SSE2 and AV_CPU_FLAG_SSE2SLOW are both set in this case
|
|
so that SSE2 is used unless explicitly disabled by checking
|
|
AV_CPU_FLAG_SSE2SLOW. */
|
|
if (!strncmp(vendor.c, "AuthenticAMD", 12) &&
|
|
rval & AV_CPU_FLAG_SSE2 && !(ecx & 0x00000040)) {
|
|
rval |= AV_CPU_FLAG_SSE2SLOW;
|
|
}
|
|
|
|
/* XOP and FMA4 use the AVX instruction coding scheme, so they can't be
|
|
* used unless the OS has AVX support. */
|
|
if (rval & AV_CPU_FLAG_AVX) {
|
|
if (ecx & 0x00000800)
|
|
rval |= AV_CPU_FLAG_XOP;
|
|
if (ecx & 0x00010000)
|
|
rval |= AV_CPU_FLAG_FMA4;
|
|
}
|
|
}
|
|
|
|
if (!strncmp(vendor.c, "GenuineIntel", 12)) {
|
|
if (family == 6 && (model == 9 || model == 13 || model == 14)) {
|
|
/* 6/9 (pentium-m "banias"), 6/13 (pentium-m "dothan"), and
|
|
* 6/14 (core1 "yonah") theoretically support sse2, but it's
|
|
* usually slower than mmx, so let's just pretend they don't.
|
|
* AV_CPU_FLAG_SSE2 is disabled and AV_CPU_FLAG_SSE2SLOW is
|
|
* enabled so that SSE2 is not used unless explicitly enabled
|
|
* by checking AV_CPU_FLAG_SSE2SLOW. The same situation
|
|
* applies for AV_CPU_FLAG_SSE3 and AV_CPU_FLAG_SSE3SLOW. */
|
|
if (rval & AV_CPU_FLAG_SSE2)
|
|
rval ^= AV_CPU_FLAG_SSE2SLOW | AV_CPU_FLAG_SSE2;
|
|
if (rval & AV_CPU_FLAG_SSE3)
|
|
rval ^= AV_CPU_FLAG_SSE3SLOW | AV_CPU_FLAG_SSE3;
|
|
}
|
|
/* The Atom processor has SSSE3 support, which is useful in many cases,
|
|
* but sometimes the SSSE3 version is slower than the SSE2 equivalent
|
|
* on the Atom, but is generally faster on other processors supporting
|
|
* SSSE3. This flag allows for selectively disabling certain SSSE3
|
|
* functions on the Atom. */
|
|
if (family == 6 && model == 28)
|
|
rval |= AV_CPU_FLAG_ATOM;
|
|
}
|
|
|
|
#endif /* cpuid */
|
|
|
|
return rval;
|
|
}
|