Move mm_support() from libavcodec to libavutil, make it a public

function and rename it to av_get_cpu_flags().

Originally committed as revision 25076 to svn://svn.ffmpeg.org/ffmpeg/trunk

1 files changed, 128 insertions, 0 deletions

diff --git a/libavutil/x86/cpu.h b/libavutil/x86/cpu.h
new file mode 100644
index 0000000000..052d2c5477
--- /dev/null
+++ b/libavutil/x86/cpu.h
@@ -0,0 +1,128 @@
+/*
+ * 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
+ */
+
+#ifndef AVUTIL_X86_CPU_H2
+#define AVUTIL_X86_CPU_H2
+
+#include <stdlib.h>
+#include "libavutil/x86_cpu.h"
+#include "libavutil/cpu.h"
+
+/* 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));
+
+/* Function to test if multimedia instructions are supported...  */
+int av_get_cpu_flags(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;
+    __asm__ volatile (
+        /* See if CPUID instruction is supported ... */
+        /* ... Get copies of EFLAGS into eax and ecx */
+        "pushfl\n\t"
+        "pop %0\n\t"
+        "mov %0, %1\n\t"
+
+        /* ... Toggle the ID bit in one copy and store */
+        /*     to the EFLAGS reg */
+        "xor $0x200000, %0\n\t"
+        "push %0\n\t"
+        "popfl\n\t"
+
+        /* ... Get the (hopefully modified) EFLAGS */
+        "pushfl\n\t"
+        "pop %0\n\t"
+        : "=a" (a), "=c" (c)
+        :
+        : "cc"
+        );
+
+    if (a == c)
+        return 0; /* CPUID not supported */
+#endif
+
+    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<<23))
+            rval |= AV_CPU_FLAG_MMX;
+        if (std_caps & (1<<25))
+            rval |= AV_CPU_FLAG_MMX2
+#if HAVE_SSE
+                  | 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;
+#endif
+                  ;
+    }
+
+    cpuid(0x80000000, max_ext_level, ebx, ecx, edx);
+
+    if(max_ext_level >= 0x80000001){
+        cpuid(0x80000001, eax, ebx, ecx, ext_caps);
+        if (ext_caps & (1<<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;
+    }
+
+    if (!strncmp(vendor.c, "GenuineIntel", 12) &&
+        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. */
+        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;
+    }
+
+    return rval;
+}
+
+#endif /* AVUTIL_X86_CPU_H2 */