libvpx: Pull from upstream

source/libvpx/vp8/encoder/x86/quantize_ssse3.c

 /*
  *  Copyright (c) 2012 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 <tmmintrin.h> /* SSSE3 */
 
 #include "vp8/encoder/block.h"
 
 /* bitscan reverse (bsr) */
 #if defined(_MSC_VER)
 #include <intrin.h>
 #pragma intrinsic(_BitScanReverse)
 static int bsr(int mask) {
   int eob;
   _BitScanReverse(&eob, mask);
   eob++;
   if (mask == 0)
     eob = 0;
   return eob;
 }
 #else
 static int bsr(int mask) {
   int eob;
+#if defined(__GNUC__) && __GNUC__
+  __asm__ __volatile__("bsr %1, %0" : "=r" (eob) : "r" (mask) : "flags");
+#elif defined(__SUNPRO_C) || defined(__SUNPRO_CC)
   asm volatile("bsr %1, %0" : "=r" (eob) : "r" (mask) : "flags");
+#endif
   eob++;
   if (mask == 0)
     eob = 0;
   return eob;
 }
 #endif
 
 void vp8_fast_quantize_b_ssse3(BLOCK *b, BLOCKD *d) {
   int eob, mask;
 
@@ skipping 60 matching lines @@
   x = _mm_packs_epi16(x0, x1);
 
   x = _mm_shuffle_epi8(x, zig_zag);
 
   mask = _mm_movemask_epi8(x);
 
   eob = bsr(mask);
 
   *d->eob = 0xFF & eob;
 }