libvpx: Pull from upstream

source/libvpx/vp9/encoder/x86/vp9_dct_ssse3.c

 /*
  *  Copyright (c) 2014 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 <assert.h>
 #if defined(_MSC_VER) && _MSC_VER <= 1500
 // Need to include math.h before calling tmmintrin.h/intrin.h
 // in certain versions of MSVS.
 #include <math.h>
 #endif
 #include <tmmintrin.h>  // SSSE3
 #include "vp9/common/x86/vp9_idct_intrin_sse2.h"
 
 void vp9_fdct8x8_quant_ssse3(const int16_t *input, int stride,
                              int16_t* coeff_ptr, intptr_t n_coeffs,
@@ skipping 346 matching lines @@
 
     // AC only loop
     index = 2;
     while (n_coeffs < 0) {
       __m128i coeff0, coeff1;
       {
         __m128i coeff0_sign, coeff1_sign;
         __m128i qcoeff0, qcoeff1;
         __m128i qtmp0, qtmp1;
 
+        assert(index < (int)(sizeof(in) / sizeof(in[0])) - 1);
         coeff0 = *in[index];
         coeff1 = *in[index + 1];
 
         // Poor man's sign extract
         coeff0_sign = _mm_srai_epi16(coeff0, 15);
         coeff1_sign = _mm_srai_epi16(coeff1, 15);
         qcoeff0 = _mm_xor_si128(coeff0, coeff0_sign);
         qcoeff1 = _mm_xor_si128(coeff1, coeff1_sign);
         qcoeff0 = _mm_sub_epi16(qcoeff0, coeff0_sign);
         qcoeff1 = _mm_sub_epi16(qcoeff1, coeff1_sign);
@@ skipping 58 matching lines @@
     do {
       _mm_store_si128((__m128i*)(dqcoeff_ptr + n_coeffs), zero);
       _mm_store_si128((__m128i*)(dqcoeff_ptr + n_coeffs) + 1, zero);
       _mm_store_si128((__m128i*)(qcoeff_ptr + n_coeffs), zero);
       _mm_store_si128((__m128i*)(qcoeff_ptr + n_coeffs) + 1, zero);
       n_coeffs += 8 * 2;
     } while (n_coeffs < 0);
     *eob_ptr = 0;
   }
 }