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Diffstat (limited to 'media/libav/libavutil/x86/cpu.c')
| -rw-r--r-- | media/libav/libavutil/x86/cpu.c | 218 |
1 files changed, 218 insertions, 0 deletions
diff --git a/media/libav/libavutil/x86/cpu.c b/media/libav/libavutil/x86/cpu.c new file mode 100644 index 000000000..8be6d9474 --- /dev/null +++ b/media/libav/libavutil/x86/cpu.c @@ -0,0 +1,218 @@ +/* + * 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 Libav. + * + * Libav 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. + * + * Libav 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 Libav; 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 (ecx & 0x00001000) + rval |= AV_CPU_FLAG_FMA3; + } + } +#endif /* HAVE_AVX */ +#endif /* HAVE_SSE */ + } + if (max_std_level >= 7) { + cpuid(7, eax, ebx, ecx, edx); +#if HAVE_AVX2 + if (ebx & 0x00000020) + rval |= AV_CPU_FLAG_AVX2; +#endif /* HAVE_AVX2 */ + /* BMI1/2 don't need OS support */ + if (ebx & 0x00000008) { + rval |= AV_CPU_FLAG_BMI1; + if (ebx & 0x00000100) + rval |= AV_CPU_FLAG_BMI2; + } + } + + 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; +} |