Prevents a segfault in the noise suppression code on ARMv7 with NEON instructions and Mips platform…

webrtc/modules/audio_processing/ns/nsx_core_mips.c

 /*
  *  Copyright (c) 2013 The WebRTC 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.
  */
 
@@ skipping 113 matching lines @@
   nShifts = 7 - inst->stages; // WIDTH_PR_MAP_SHIFT - inst->stages + 5;
   //use larger width in tanh map for pause regions
   if (tmp32no1 < 0) {
     tmpIndFX = 0;
     tmp32no1 = -tmp32no1;
     //widthPrior = widthPrior * 2.0;
     nShifts++;
   }
   tmp32no1 = WEBRTC_SPL_SHIFT_W32(tmp32no1, nShifts); // Q14
   // compute indicator function: sigmoid map
-  tableIndex = (int16_t)(tmp32no1 >> 14);
-  if ((tableIndex < 16) && (tableIndex >= 0)) {
+  if (tmp32no1 < (16<<14) && tmp32no1 >= 0) {
+    tableIndex = (int16_t)(tmp32no1 >> 14);
     tmp16no2 = kIndicatorTable[tableIndex];
     tmp16no1 = kIndicatorTable[tableIndex + 1] - kIndicatorTable[tableIndex];
     frac = (int16_t)(tmp32no1 & 0x00003fff); // Q14
     tmp16no2 += (int16_t)((tmp16no1 * frac) >> 14);
     if (tmpIndFX == 0) {
       tmpIndFX = 8192 - tmp16no2; // Q14
     } else {
       tmpIndFX = 8192 + tmp16no2; // Q14
     }
   }
@@ skipping 10 matching lines @@
       tmpIndFX = 0;
       tmpU32no2 = tmpU32no1 - inst->thresholdSpecFlat;
       //widthPrior = widthPrior * 2.0;
       nShifts++;
     }
     tmpU32no1 = WebRtcSpl_DivU32U16(tmpU32no2 << nShifts, 25);  //Q14
     // compute indicator function: sigmoid map
     // FLOAT code
     // indicator1 = 0.5 * (tanh(sgnMap * widthPrior *
     //                          (threshPrior1 - tmpFloat1)) + 1.0);
-    tableIndex = (int16_t)(tmpU32no1 >> 14);
-    if (tableIndex < 16) {
+    if (tmp32no1 < (16<<14) && tmp32no1 >= 0) {

[hlundin-webrtc, 2016/04/15 08:28:31]

This is wrong. The old code deals with tmpU32no1, not tmp32no1. And you should
then not check for non-negativity.

[ivoc, 2016/04/15 08:37:25]

Oops, you're right. These wonderfully descriptive variable names make it easy to
miss.

+      tableIndex = (int16_t)(tmp32no1 >> 14);
       tmp16no2 = kIndicatorTable[tableIndex];
       tmp16no1 = kIndicatorTable[tableIndex + 1] - kIndicatorTable[tableIndex];
       frac = (int16_t)(tmpU32no1 & 0x00003fff); // Q14
       tmp16no2 += (int16_t)((tmp16no1 * frac) >> 14);
       if (tmpIndFX) {
         tmpIndFX = 8192 + tmp16no2; // Q14
       } else {
         tmpIndFX = 8192 - tmp16no2; // Q14
       }
     }
@@ skipping 25 matching lines @@
       tmpIndFX = 0;
       tmpU32no2 = tmpU32no3 - tmpU32no1;
       //widthPrior = widthPrior * 2.0;
       nShifts--;
     }
     tmpU32no1 = tmpU32no2 >> nShifts;
     // compute indicator function: sigmoid map
     /* FLOAT code
      indicator2 = 0.5 * (tanh(widthPrior * (tmpFloat1 - threshPrior2)) + 1.0);
      */
-    tableIndex = (int16_t)(tmpU32no1 >> 14);
-    if (tableIndex < 16) {
+    if (tmp32no1 < (16<<14) && tmp32no1 >= 0) {

[hlundin-webrtc, 2016/04/15 08:28:31]

Same here. Wrong variable.

[ivoc, 2016/04/15 08:37:25]

Fixed.

+      tableIndex = (int16_t)(tmp32no1 >> 14);
       tmp16no2 = kIndicatorTable[tableIndex];
       tmp16no1 = kIndicatorTable[tableIndex + 1] - kIndicatorTable[tableIndex];
       frac = (int16_t)(tmpU32no1 & 0x00003fff); // Q14
       tmp16no2 += (int16_t)WEBRTC_SPL_MUL_16_16_RSFT_WITH_ROUND(
                     tmp16no1, frac, 14);
       if (tmpIndFX) {
         tmpIndFX = 8192 + tmp16no2;
       } else {
         tmpIndFX = 8192 - tmp16no2;
       }
@@ skipping 768 matching lines @@
    "4:                                                 \n\t"
     ".set          pop                                 \n\t"
     : [t0] "=&r" (t0), [r0] "=&r" (r0), [r1] "=&r" (r1),
       [r2] "=&r" (r2), [r3] "=&r" (r3)
     : [len] "r" (len), [shift] "r" (shift), [in] "r" (in),
       [out] "r" (out)
     : "memory"
   );
 }