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mirror of https://github.com/FFmpeg/FFmpeg.git synced 2024-12-18 03:19:31 +02:00
FFmpeg/libavutil/x86/cpu.c
Michael Niedermayer b27c7d70d8 Merge remote-tracking branch 'qatar/master'
* qatar/master:
  mss1: fix decoding masked regions in interframes
  mxfdec: fix off by one error.
  mxfdec: only parse next partition pack if parsing forward
  mxfdec: let pkt->pts = mxf->current_edit_unit if intra-only
  mxfdec: fix frame height vs field height confusion
  mxfdec: Add intra_only flag to MXFTrack
  mxfdec: fix Avid AirSpeed files being misinterpreted as OP1a
  mxfdec: truncate packets that extend past the next edit unit
  mxfdec: set pixel format for cdci picture formats
  mxfdec: detect uncomp pictures using essence container ul
  mxfdec: set track edit rate num/den in expected order
  x86/cpu: implement get/set_eflags using intrinsics
  x86/cpu: implement support for cpuid through intrinsics
  x86/cpu: implement support for xgetbv through intrinsics
  lavu: use intrinsics for emms on systems lacking inline asm support
  mem: Don't abort on av_malloc(0) in debug mode

Conflicts:
	configure
	libavformat/mxf.h
	libavformat/mxfdec.c

Merged-by: Michael Niedermayer <michaelni@gmx.at>
2012-07-10 20:51:51 +02:00

211 lines
7.4 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_cpu.h"
#include "libavutil/cpu.h"
#if 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))
#elif HAVE_CPUID
#include <intrin.h>
#define cpuid(index, eax, ebx, ecx, edx) \
do { \
int info[4]; \
__cpuid(info, index); \
eax = info[0]; \
ebx = info[1]; \
ecx = info[2]; \
edx = info[3]; \
} while (0)
#endif /* HAVE_CPUID */
#if HAVE_INLINE_ASM
#define xgetbv(index, eax, edx) \
__asm__ (".byte 0x0f, 0x01, 0xd0" : "=a"(eax), "=d"(edx) : "c" (index))
#elif HAVE_XGETBV
#include <immintrin.h>
#define xgetbv(index, eax, edx) \
do { \
uint64_t res = __xgetbv(index); \
eax = res; \
edx = res >> 32; \
} while (0)
#endif /* HAVE_XGETBV */
#if HAVE_INLINE_ASM
#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))
#elif HAVE_RWEFLAGS
#include <intrin.h>
#define get_eflags(x) \
x = __readeflags()
#define set_eflags(x) \
__writeeflags(x)
#endif /* HAVE_INLINE_ASM */
/* Function to test if multimedia instructions are supported... */
int ff_get_cpu_flags_x86(void)
{
int rval = 0;
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 ARCH_X86_32
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);
if (a == c)
return 0; /* CPUID not supported */
#endif
cpuid(0, max_std_level, ebx, ecx, edx);
vendor.i[0] = ebx;
vendor.i[1] = edx;
vendor.i[2] = ecx;
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_MMX2;
#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;
}
#endif
#endif
}
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_MMX2;
/* 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;
}
return rval;
}