The Tor Browser: media/libvpx/vpx_ports/arm_cpudetect.c@6474c204b198 (annotated)

media/libvpx/vpx_ports/arm_cpudetect.c@6474c204b198 (annotated)

media/libvpx/vpx_ports/arm_cpudetect.c

Wed, 31 Dec 2014 06:09:35 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Wed, 31 Dec 2014 06:09:35 +0100
changeset 0: 6474c204b198
permissions: -rw-r--r--

Cloned upstream origin tor-browser at tor-browser-31.3.0esr-4.5-1-build1
revision ID fc1c9ff7c1b2defdbc039f12214767608f46423f for hacking purpose.

 /*
  *  Copyright (c) 2010 The WebM project authors. All Rights Reserved.
  *
  *  Use of this source code is governed by a BSD-style license
  *  that can be found in the LICENSE file in the root of the source
  *  tree. An additional intellectual property rights grant can be found
  *  in the file PATENTS.  All contributing project authors may
  *  be found in the AUTHORS file in the root of the source tree.
  */
 #include <stdlib.h>
 #include <string.h>
 #include "arm.h"
 static int arm_cpu_env_flags(int *flags) {
   char *env;
   env = getenv("VPX_SIMD_CAPS");
   if (env && *env) {
     *flags = (int)strtol(env, NULL, 0);
     return 0;
   }
   *flags = 0;
   return -1;
 }
 static int arm_cpu_env_mask(void) {
   char *env;
   env = getenv("VPX_SIMD_CAPS_MASK");
   return env && *env ? (int)strtol(env, NULL, 0) : ~0;
 }
 #if !CONFIG_RUNTIME_CPU_DETECT
 int arm_cpu_caps(void) {
   /* This function should actually be a no-op. There is no way to adjust any of
    * these because the RTCD tables do not exist: the functions are called
    * statically */
   int flags;
   int mask;
   if (!arm_cpu_env_flags(&flags)) {
     return flags;
   }
   mask = arm_cpu_env_mask();
 #if HAVE_EDSP
   flags |= HAS_EDSP;
 #endif /* HAVE_EDSP */
 #if HAVE_MEDIA
   flags |= HAS_MEDIA;
 #endif /* HAVE_MEDIA */
 #if HAVE_NEON
   flags |= HAS_NEON;
 #endif /* HAVE_NEON */
   return flags & mask;
 }
 #elif defined(_MSC_VER) /* end !CONFIG_RUNTIME_CPU_DETECT */
 /*For GetExceptionCode() and EXCEPTION_ILLEGAL_INSTRUCTION.*/
 #define WIN32_LEAN_AND_MEAN
 #define WIN32_EXTRA_LEAN
 #include <windows.h>
 int arm_cpu_caps(void) {
   int flags;
   int mask;
   if (!arm_cpu_env_flags(&flags)) {
     return flags;
   }
   mask = arm_cpu_env_mask();
   /* MSVC has no inline __asm support for ARM, but it does let you __emit
    *  instructions via their assembled hex code.
    * All of these instructions should be essentially nops.
    */
 #if HAVE_EDSP
   if (mask & HAS_EDSP) {
     __try {
       /*PLD [r13]*/
       __emit(0xF5DDF000);
       flags |= HAS_EDSP;
     } __except (GetExceptionCode() == EXCEPTION_ILLEGAL_INSTRUCTION) {
       /*Ignore exception.*/
     }
   }
 #if HAVE_MEDIA
   if (mask & HAS_MEDIA)
     __try {
       /*SHADD8 r3,r3,r3*/
       __emit(0xE6333F93);
       flags |= HAS_MEDIA;
     } __except (GetExceptionCode() == EXCEPTION_ILLEGAL_INSTRUCTION) {
     /*Ignore exception.*/
   }
 }
 #if HAVE_NEON
 if (mask &HAS_NEON) {
   __try {
     /*VORR q0,q0,q0*/
     __emit(0xF2200150);
     flags |= HAS_NEON;
   } __except (GetExceptionCode() == EXCEPTION_ILLEGAL_INSTRUCTION) {
     /*Ignore exception.*/
   }
 }
 #endif /* HAVE_NEON */
 #endif /* HAVE_MEDIA */
 #endif /* HAVE_EDSP */
 return flags & mask;
 }
 #elif defined(__ANDROID__) /* end _MSC_VER */
 #include <cpu-features.h>
 int arm_cpu_caps(void) {
   int flags;
   int mask;
   uint64_t features;
   if (!arm_cpu_env_flags(&flags)) {
     return flags;
   }
   mask = arm_cpu_env_mask();
   features = android_getCpuFeatures();
 #if HAVE_EDSP
   flags |= HAS_EDSP;
 #endif /* HAVE_EDSP */
 #if HAVE_MEDIA
   flags |= HAS_MEDIA;
 #endif /* HAVE_MEDIA */
 #if HAVE_NEON
   if (features & ANDROID_CPU_ARM_FEATURE_NEON)
     flags |= HAS_NEON;
 #endif /* HAVE_NEON */
   return flags & mask;
 }
 #elif defined(__linux__) /* end __ANDROID__ */
 #include <stdio.h>
 int arm_cpu_caps(void) {
   FILE *fin;
   int flags;
   int mask;
   if (!arm_cpu_env_flags(&flags)) {
     return flags;
   }
   mask = arm_cpu_env_mask();
   /* Reading /proc/self/auxv would be easier, but that doesn't work reliably
    *  on Android.
    * This also means that detection will fail in Scratchbox.
    */
   fin = fopen("/proc/cpuinfo", "r");
   if (fin != NULL) {
     /* 512 should be enough for anybody (it's even enough for all the flags
      * that x86 has accumulated... so far).
      */
     char buf[512];
     while (fgets(buf, 511, fin) != NULL) {
 #if HAVE_EDSP || HAVE_NEON
       if (memcmp(buf, "Features", 8) == 0) {
         char *p;
 #if HAVE_EDSP
         p = strstr(buf, " edsp");
         if (p != NULL && (p[5] == ' ' || p[5] == '\n')) {
           flags |= HAS_EDSP;
         }
 #if HAVE_NEON
         p = strstr(buf, " neon");
         if (p != NULL && (p[5] == ' ' || p[5] == '\n')) {
           flags |= HAS_NEON;
         }
 #endif /* HAVE_NEON */
 #endif /* HAVE_EDSP */
       }
 #endif /* HAVE_EDSP || HAVE_NEON */
 #if HAVE_MEDIA
       if (memcmp(buf, "CPU architecture:", 17) == 0) {
         int version;
         version = atoi(buf + 17);
         if (version >= 6) {
           flags |= HAS_MEDIA;
         }
       }
 #endif /* HAVE_MEDIA */
     }
     fclose(fin);
   }
   return flags & mask;
 }
 #else /* end __linux__ */
 #error "--enable-runtime-cpu-detect selected, but no CPU detection method " \
 "available for your platform. Reconfigure with --disable-runtime-cpu-detect."
 #endif

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media/libvpx/vpx_ports/arm_cpudetect.c@6474c204b198 (annotated)

media/libvpx/vpx_ports/arm_cpudetect.c