Prepare to convert various types to size_t.

This makes some behaviorally-invariant changes to make certain code that
currently only works correctly with signed types work safely regardless of the
signedness of the types in question.  This is preparation for a future change
that will convert a variety of types to size_t.

There are also some formatting changes (e.g. converting "enum hack" usage to real consts) to make it simpler to just change "int" to "size_t" in the future to change the types of those constants.

BUG=none
R=andrew@webrtc.org, juberti@webrtc.org, kwiberg@webrtc.org
TBR=ajm

Review URL: https://codereview.webrtc.org/1174813003

Cr-Commit-Position: refs/heads/master@{#9413}
diff --git a/webrtc/modules/audio_coding/codecs/audio_decoder.cc b/webrtc/modules/audio_coding/codecs/audio_decoder.cc
index 9e88f89..0a4a6a9 100644
--- a/webrtc/modules/audio_coding/codecs/audio_decoder.cc
+++ b/webrtc/modules/audio_coding/codecs/audio_decoder.cc
@@ -56,7 +56,7 @@
 
 bool AudioDecoder::HasDecodePlc() const { return false; }
 
-int AudioDecoder::DecodePlc(int num_frames, int16_t* decoded) { return -1; }
+int AudioDecoder::DecodePlc(int num_frames, int16_t* decoded) { return 0; }
 
 int AudioDecoder::IncomingPacket(const uint8_t* payload,
                                  size_t payload_len,
diff --git a/webrtc/modules/audio_coding/codecs/cng/audio_encoder_cng.cc b/webrtc/modules/audio_coding/codecs/cng/audio_encoder_cng.cc
index 9b23607..c662b5b 100644
--- a/webrtc/modules/audio_coding/codecs/cng/audio_encoder_cng.cc
+++ b/webrtc/modules/audio_coding/codecs/cng/audio_encoder_cng.cc
@@ -136,9 +136,9 @@
       (frames_to_encode > 3 ? 3 : frames_to_encode);
   if (frames_to_encode == 4)
     blocks_in_first_vad_call = 2;
+  CHECK_GE(frames_to_encode, blocks_in_first_vad_call);
   const int blocks_in_second_vad_call =
       frames_to_encode - blocks_in_first_vad_call;
-  CHECK_GE(blocks_in_second_vad_call, 0);
 
   // Check if all of the buffer is passive speech. Start with checking the first
   // block.
@@ -217,7 +217,7 @@
     info = speech_encoder_->Encode(
         rtp_timestamps_.front(), &speech_buffer_[i * samples_per_10ms_frame],
         samples_per_10ms_frame, max_encoded_bytes, encoded);
-    if (i == frames_to_encode - 1) {
+    if (i + 1 == frames_to_encode) {
       CHECK_GT(info.encoded_bytes, 0u) << "Encoder didn't deliver data.";
     } else {
       CHECK_EQ(info.encoded_bytes, 0u) << "Encoder delivered data too early.";
diff --git a/webrtc/modules/audio_coding/codecs/g711/audio_encoder_pcm.cc b/webrtc/modules/audio_coding/codecs/g711/audio_encoder_pcm.cc
index 0a3a639..ed49618 100644
--- a/webrtc/modules/audio_coding/codecs/g711/audio_encoder_pcm.cc
+++ b/webrtc/modules/audio_coding/codecs/g711/audio_encoder_pcm.cc
@@ -88,13 +88,13 @@
   }
   CHECK_EQ(speech_buffer_.size(), full_frame_samples_);
   CHECK_GE(max_encoded_bytes, full_frame_samples_);
-  int16_t ret = EncodeCall(&speech_buffer_[0], full_frame_samples_, encoded);
-  CHECK_GE(ret, 0);
-  speech_buffer_.clear();
   EncodedInfo info;
   info.encoded_timestamp = first_timestamp_in_buffer_;
   info.payload_type = payload_type_;
+  int16_t ret = EncodeCall(&speech_buffer_[0], full_frame_samples_, encoded);
+  CHECK_GE(ret, 0);
   info.encoded_bytes = static_cast<size_t>(ret);
+  speech_buffer_.clear();
   return info;
 }
 
diff --git a/webrtc/modules/audio_coding/codecs/g711/test/testG711.cc b/webrtc/modules/audio_coding/codecs/g711/test/testG711.cc
index e891810..9511df7 100644
--- a/webrtc/modules/audio_coding/codecs/g711/test/testG711.cc
+++ b/webrtc/modules/audio_coding/codecs/g711/test/testG711.cc
@@ -86,6 +86,10 @@
   printf("G.711 version: %s\n\n", versionNumber);
   /* Get frame length */
   framelength = atoi(argv[1]);
+  if (framelength < 0) {
+    printf("  G.711: Invalid framelength %d.\n", framelength);
+    exit(1);
+  }
 
   /* Get compression law */
   strcpy(law, argv[2]);
diff --git a/webrtc/modules/audio_coding/codecs/g722/audio_encoder_g722.cc b/webrtc/modules/audio_coding/codecs/g722/audio_encoder_g722.cc
index effb405..8e10dff 100644
--- a/webrtc/modules/audio_coding/codecs/g722/audio_encoder_g722.cc
+++ b/webrtc/modules/audio_coding/codecs/g722/audio_encoder_g722.cc
@@ -24,7 +24,8 @@
 }  // namespace
 
 bool AudioEncoderG722::Config::IsOk() const {
-  return (frame_size_ms % 10 == 0) && (num_channels >= 1);
+  return (frame_size_ms > 0) && (frame_size_ms % 10 == 0) &&
+      (num_channels >= 1);
 }
 
 AudioEncoderG722::EncoderState::EncoderState() {
diff --git a/webrtc/modules/audio_coding/codecs/g722/test/testG722.cc b/webrtc/modules/audio_coding/codecs/g722/test/testG722.cc
index 6d0c432..9b2f54c 100644
--- a/webrtc/modules/audio_coding/codecs/g722/test/testG722.cc
+++ b/webrtc/modules/audio_coding/codecs/g722/test/testG722.cc
@@ -83,6 +83,10 @@
 
     /* Get frame length */
     framelength = atoi(argv[1]);
+    if (framelength < 0) {
+        printf("  G.722: Invalid framelength %d.\n", framelength);
+        exit(1);
+    }
 
     /* Get Input and Output files */
     sscanf(argv[2], "%s", inname);
diff --git a/webrtc/modules/audio_coding/codecs/ilbc/cb_mem_energy_calc.c b/webrtc/modules/audio_coding/codecs/ilbc/cb_mem_energy_calc.c
index b675441..bfe0e64 100644
--- a/webrtc/modules/audio_coding/codecs/ilbc/cb_mem_energy_calc.c
+++ b/webrtc/modules/audio_coding/codecs/ilbc/cb_mem_energy_calc.c
@@ -41,7 +41,7 @@
   eSh_ptr  = &energyShifts[1+base_size];
   eW16_ptr = &energyW16[1+base_size];
 
-  for(j=0;j<range-1;j++) {
+  for (j = 0; j + 1 < range; j++) {
 
     /* Calculate next energy by a +/-
        operation on the edge samples */
diff --git a/webrtc/modules/audio_coding/codecs/ilbc/cb_search.c b/webrtc/modules/audio_coding/codecs/ilbc/cb_search.c
index 2a77f4f..877a1c6 100644
--- a/webrtc/modules/audio_coding/codecs/ilbc/cb_search.c
+++ b/webrtc/modules/audio_coding/codecs/ilbc/cb_search.c
@@ -227,12 +227,9 @@
         inverseEnergy[indexNew+indexOffset], inverseEnergyShifts[indexNew+indexOffset],
         &CritMax, &shTotMax, &bestIndex, &bestGain);
 
-    sInd=bestIndex-(int16_t)(CB_RESRANGE>>1);
+    sInd = ((CB_RESRANGE >> 1) > bestIndex) ?
+        0 : (bestIndex - (CB_RESRANGE >> 1));
     eInd=sInd+CB_RESRANGE;
-    if (sInd<0) {
-      eInd-=sInd;
-      sInd=0;
-    }
     if (eInd>=range) {
       eInd=range-1;
       sInd=eInd-CB_RESRANGE;
@@ -247,9 +244,11 @@
                                       interpSamplesFilt, cDot,
                                       (int16_t)(sInd+20), (int16_t)(WEBRTC_SPL_MIN(39, (eInd+20))), scale);
         i=20;
+        cDotPtr = &cDot[20 - sInd];
+      } else {
+        cDotPtr = cDot;
       }
 
-      cDotPtr=&cDot[WEBRTC_SPL_MAX(0,(20-sInd))];
       cb_vecPtr = cbvectors+lMem-20-i;
 
       /* Calculate the cross correlations (main part of the filtered CB) */
diff --git a/webrtc/modules/audio_coding/codecs/ilbc/decode_residual.c b/webrtc/modules/audio_coding/codecs/ilbc/decode_residual.c
index 169218a..c04fd99 100644
--- a/webrtc/modules/audio_coding/codecs/ilbc/decode_residual.c
+++ b/webrtc/modules/audio_coding/codecs/ilbc/decode_residual.c
@@ -41,7 +41,7 @@
     int16_t *syntdenum   /* (i) the decoded synthesis filter
                                   coefficients */
                                   ) {
-  int16_t meml_gotten, Nfor, Nback, diff, start_pos;
+  int16_t meml_gotten, diff, start_pos;
   int16_t subcount, subframe;
   int16_t *reverseDecresidual = iLBCdec_inst->enh_buf; /* Reversed decoded data, used for decoding backwards in time (reuse memory in state) */
   int16_t *memVec = iLBCdec_inst->prevResidual;  /* Memory for codebook and filter state (reuse memory in state) */
@@ -110,9 +110,7 @@
 
   /* forward prediction of subframes */
 
-  Nfor = iLBCdec_inst->nsub-iLBC_encbits->startIdx-1;
-
-  if( Nfor > 0 ) {
+  if (iLBCdec_inst->nsub > iLBC_encbits->startIdx + 1) {
 
     /* setup memory */
     WebRtcSpl_MemSetW16(mem, 0, CB_MEML-STATE_LEN);
@@ -121,6 +119,7 @@
 
     /* loop over subframes to encode */
 
+    int16_t Nfor = iLBCdec_inst->nsub - iLBC_encbits->startIdx - 1;
     for (subframe=0; subframe<Nfor; subframe++) {
 
       /* construct decoded vector */
@@ -143,9 +142,7 @@
 
   /* backward prediction of subframes */
 
-  Nback = iLBC_encbits->startIdx-1;
-
-  if( Nback > 0 ){
+  if (iLBC_encbits->startIdx > 1) {
 
     /* setup memory */
 
@@ -160,6 +157,7 @@
 
     /* loop over subframes to decode */
 
+    int16_t Nback = iLBC_encbits->startIdx - 1;
     for (subframe=0; subframe<Nback; subframe++) {
 
       /* construct decoded vector */
diff --git a/webrtc/modules/audio_coding/codecs/ilbc/do_plc.c b/webrtc/modules/audio_coding/codecs/ilbc/do_plc.c
index 2d72075..ecdd68a 100644
--- a/webrtc/modules/audio_coding/codecs/ilbc/do_plc.c
+++ b/webrtc/modules/audio_coding/codecs/ilbc/do_plc.c
@@ -37,7 +37,7 @@
     IlbcDecoder *iLBCdec_inst
     /* (i/o) decoder instance */
                             ){
-  int16_t i, pick;
+  int16_t i;
   int32_t cross, ener, cross_comp, ener_comp = 0;
   int32_t measure, maxMeasure, energy;
   int16_t max, crossSquareMax, crossSquare;
@@ -234,22 +234,19 @@
       /* noise component -  52 < randlagFIX < 117 */
       iLBCdec_inst->seed = (int16_t)(iLBCdec_inst->seed * 31821 + 13849);
       randlag = 53 + (int16_t)(iLBCdec_inst->seed & 63);
-
-      pick = i - randlag;
-
-      if (pick < 0) {
-        randvec[i] = iLBCdec_inst->prevResidual[iLBCdec_inst->blockl+pick];
+      if (randlag > i) {
+        randvec[i] =
+            iLBCdec_inst->prevResidual[iLBCdec_inst->blockl + i - randlag];
       } else {
-        randvec[i] = iLBCdec_inst->prevResidual[pick];
+        randvec[i] = iLBCdec_inst->prevResidual[i - randlag];
       }
 
       /* pitch repeatition component */
-      pick = i - use_lag;
-
-      if (pick < 0) {
-        PLCresidual[i] = iLBCdec_inst->prevResidual[iLBCdec_inst->blockl+pick];
+      if (use_lag > i) {
+        PLCresidual[i] =
+            iLBCdec_inst->prevResidual[iLBCdec_inst->blockl + i - use_lag];
       } else {
-        PLCresidual[i] = PLCresidual[pick];
+        PLCresidual[i] = PLCresidual[i - use_lag];
       }
 
       /* Attinuate total gain for each 10 ms */
diff --git a/webrtc/modules/audio_coding/codecs/ilbc/encode.c b/webrtc/modules/audio_coding/codecs/ilbc/encode.c
index 1d46eff..3de8425 100644
--- a/webrtc/modules/audio_coding/codecs/ilbc/encode.c
+++ b/webrtc/modules/audio_coding/codecs/ilbc/encode.c
@@ -48,7 +48,7 @@
     IlbcEncoder *iLBCenc_inst /* (i/o) the general encoder
                                      state */
                           ){
-  int n, meml_gotten, Nfor, Nback;
+  int n, meml_gotten, Nfor;
   int16_t diff, start_pos;
   int index;
   int subcount, subframe;
@@ -379,15 +379,14 @@
 
   /* backward prediction of subframes */
 
-  Nback = iLBCbits_inst->startIdx-1;
-
-  if( Nback > 0 ){
+  if (iLBCbits_inst->startIdx > 1) {
 
     /* create reverse order vectors
        (The decresidual does not need to be copied since it is
        contained in the same vector as the residual)
     */
 
+    int Nback = iLBCbits_inst->startIdx - 1;
     WebRtcSpl_MemCpyReversedOrder(&reverseResidual[Nback*SUBL-1], residual, Nback*SUBL);
 
     /* setup memory */
@@ -425,11 +424,11 @@
       if (iLBCenc_inst->section == 1)
       {
         start_count = 0;
-        end_count = WEBRTC_SPL_MAX (2 - Nfor, 0);
+        end_count = (Nfor >= 2) ? 0 : (2 - NFor);
       }
       if (iLBCenc_inst->section == 2)
       {
-        start_count = WEBRTC_SPL_MAX (2 - Nfor, 0);
+        start_count = (Nfor >= 2) ? 0 : (2 - NFor);
         end_count = Nback;
       }
     }
diff --git a/webrtc/modules/audio_coding/codecs/ilbc/enhancer_interface.c b/webrtc/modules/audio_coding/codecs/ilbc/enhancer_interface.c
index db4b8d4..257013c 100644
--- a/webrtc/modules/audio_coding/codecs/ilbc/enhancer_interface.c
+++ b/webrtc/modules/audio_coding/codecs/ilbc/enhancer_interface.c
@@ -110,9 +110,8 @@
   for(iblock = 0; iblock<new_blocks; iblock++){
 
     /* references */
-    i = 60 + iblock * ENH_BLOCKL_HALF;
-    target=downsampled+i;
-    regressor=downsampled+i-10;
+    target = downsampled + 60 + iblock * ENH_BLOCKL_HALF;
+    regressor = target - 10;
 
     /* scaling */
     max16=WebRtcSpl_MaxAbsValueW16(&regressor[-50],
diff --git a/webrtc/modules/audio_coding/codecs/ilbc/test/iLBC_test.c b/webrtc/modules/audio_coding/codecs/ilbc/test/iLBC_test.c
index 3daf186..9c42037 100644
--- a/webrtc/modules/audio_coding/codecs/ilbc/test/iLBC_test.c
+++ b/webrtc/modules/audio_coding/codecs/ilbc/test/iLBC_test.c
@@ -165,6 +165,10 @@
 
     fprintf(stderr, "--- Encoding block %i --- ",blockcount);
     len = WebRtcIlbcfix_Encode(Enc_Inst, data, (int16_t)frameLen, encoded_data);
+    if (len < 0) {
+      fprintf(stderr, "Error encoding\n");
+      exit(0);
+    }
     fprintf(stderr, "\r");
 
     /* write byte file */
@@ -202,6 +206,10 @@
     if (pli==1) {
       len=WebRtcIlbcfix_Decode(Dec_Inst, encoded_data,
                                (int16_t)len, decoded_data,&speechType);
+      if (len < 0) {
+        fprintf(stderr, "Error decoding\n");
+        exit(0);
+      }
     } else {
       len=WebRtcIlbcfix_DecodePlc(Dec_Inst, decoded_data, 1);
     }
diff --git a/webrtc/modules/audio_coding/codecs/ilbc/test/iLBC_testLib.c b/webrtc/modules/audio_coding/codecs/ilbc/test/iLBC_testLib.c
index 1e966a7..103a136 100644
--- a/webrtc/modules/audio_coding/codecs/ilbc/test/iLBC_testLib.c
+++ b/webrtc/modules/audio_coding/codecs/ilbc/test/iLBC_testLib.c
@@ -139,6 +139,10 @@
 #else
     len=WebRtcIlbcfix_Encode(Enc_Inst, data, (short)(mode<<3), encoded_data);
 #endif
+    if (len < 0) {
+      fprintf(stderr, "Error encoding\n");
+      exit(0);
+    }
     fprintf(stderr, "\r");
 
 #ifdef JUNK_DATA
@@ -176,6 +180,10 @@
       if (pli==1) {
         len=WebRtcIlbcfix_Decode(Dec_Inst, encoded_data, (int16_t)len, data,
                                  &speechType);
+        if (len < 0) {
+          fprintf(stderr, "Error decoding\n");
+          exit(0);
+        }
       } else {
         len=WebRtcIlbcfix_DecodePlc(Dec_Inst, data, 1);
       }
diff --git a/webrtc/modules/audio_coding/codecs/isac/fix/source/codec.h b/webrtc/modules/audio_coding/codecs/isac/fix/source/codec.h
index 3d003e4..8c5c7e6 100644
--- a/webrtc/modules/audio_coding/codecs/isac/fix/source/codec.h
+++ b/webrtc/modules/audio_coding/codecs/isac/fix/source/codec.h
@@ -37,8 +37,8 @@
                              int16_t* current_framesamples);
 
 int16_t WebRtcIsacfix_DecodePlcImpl(int16_t* decoded,
-                                          IsacFixDecoderInstance* ISACdec_obj,
-                                          int16_t* current_framesample );
+                                    IsacFixDecoderInstance* ISACdec_obj,
+                                    int16_t* current_framesample );
 
 int WebRtcIsacfix_EncodeImpl(int16_t* in,
                              IsacFixEncoderInstance* ISACenc_obj,
diff --git a/webrtc/modules/audio_coding/codecs/isac/fix/source/decode_plc.c b/webrtc/modules/audio_coding/codecs/isac/fix/source/decode_plc.c
index 75ae542..d2cfb3a 100644
--- a/webrtc/modules/audio_coding/codecs/isac/fix/source/decode_plc.c
+++ b/webrtc/modules/audio_coding/codecs/isac/fix/source/decode_plc.c
@@ -309,7 +309,7 @@
         &((ISACdec_obj->plcstr_obj).prevPitchInvIn[FRAMESAMPLES_HALF - lag0]);
     minCorr = WEBRTC_SPL_WORD32_MAX;
 
-    if ( (FRAMESAMPLES_HALF - 2*lag0 - 10) > 0 )
+    if ((FRAMESAMPLES_HALF - 10) > 2 * lag0)
     {
       minIdx = 11;
       for( i = 0; i < 21; i++ )
diff --git a/webrtc/modules/audio_coding/codecs/isac/fix/source/lattice.c b/webrtc/modules/audio_coding/codecs/isac/fix/source/lattice.c
index cfd9a9e..3b26a98 100644
--- a/webrtc/modules/audio_coding/codecs/isac/fix/source/lattice.c
+++ b/webrtc/modules/audio_coding/codecs/isac/fix/source/lattice.c
@@ -279,13 +279,15 @@
       ARfQ0vec[i] = (int16_t)WebRtcSpl_SatW32ToW16(tmp32); // Q0
     }
 
-    for (i=orderCoef-1;i>=0;i--) //get the state of f&g for the first input, for all orders
+    for (i=orderCoef;i>0;i--) //get the state of f&g for the first input, for all orders
     {
-      tmp32 = (cthQ15[i] * ARfQ0vec[0] - sthQ15[i] * stateGQ0[i] + 16384) >> 15;
+      tmp32 = (cthQ15[i - 1] * ARfQ0vec[0] - sthQ15[i - 1] * stateGQ0[i - 1] +
+               16384) >> 15;
       tmpAR = (int16_t)WebRtcSpl_SatW32ToW16(tmp32); // Q0
 
-      tmp32 = (sthQ15[i] * ARfQ0vec[0] + cthQ15[i] * stateGQ0[i] + 16384) >> 15;
-      ARgQ0vec[i+1] = (int16_t)WebRtcSpl_SatW32ToW16(tmp32); // Q0
+      tmp32 = (sthQ15[i - 1] * ARfQ0vec[0] + cthQ15[i - 1] * stateGQ0[i - 1] +
+               16384) >> 15;
+      ARgQ0vec[i] = (int16_t)WebRtcSpl_SatW32ToW16(tmp32); // Q0
       ARfQ0vec[0] = tmpAR;
     }
     ARgQ0vec[0] = ARfQ0vec[0];
diff --git a/webrtc/modules/audio_coding/codecs/isac/fix/source/lattice_armv7.S b/webrtc/modules/audio_coding/codecs/isac/fix/source/lattice_armv7.S
index 35fd9ef..ccea467 100644
--- a/webrtc/modules/audio_coding/codecs/isac/fix/source/lattice_armv7.S
+++ b/webrtc/modules/audio_coding/codecs/isac/fix/source/lattice_armv7.S
@@ -46,21 +46,21 @@
   add     r2, r9, asl #1         @ Restore r2 to &cth_Q15[order_coef]
   add     r3, r9, asl #1         @ Restore r3 to &sth_Q15[order_coef]
 
-ORDER_COEF_LOOP:  @ for(k = order_coef - 1 ; k >= 0; k--)
+ORDER_COEF_LOOP:  @ for(k = order_coef ; k > 0; k--)
 
-  ldrh    r7, [r3, #-2]!         @ sth_Q15[k]
-  ldrh    r6, [r2, #-2]!         @ cth_Q15[k]
+  ldrh    r7, [r3, #-2]!         @ sth_Q15[k - 1]
+  ldrh    r6, [r2, #-2]!         @ cth_Q15[k - 1]
 
-  ldrh    r8, [r0, #-2]          @ ar_g_Q0[k]
-  smlabb  r11, r7, r5, r12       @ sth_Q15[k] * tmpAR + 16384
-  smlabb  r10, r6, r5, r12       @ cth_Q15[k] * tmpAR + 16384
-  smulbb  r7, r7, r8             @ sth_Q15[k] * ar_g_Q0[k]
-  smlabb  r11, r6, r8, r11       @ cth_Q15[k]*ar_g_Q0[k]+(sth_Q15[k]*tmpAR+16384)
+  ldrh    r8, [r0, #-2]          @ ar_g_Q0[k - 1]
+  smlabb  r11, r7, r5, r12       @ sth_Q15[k - 1] * tmpAR + 16384
+  smlabb  r10, r6, r5, r12       @ cth_Q15[k - 1] * tmpAR + 16384
+  smulbb  r7, r7, r8             @ sth_Q15[k - 1] * ar_g_Q0[k - 1]
+  smlabb  r11, r6, r8, r11       @ cth_Q15[k - 1]*ar_g_Q0[k - 1]+(sth_Q15[k - 1]*tmpAR+16384)
 
-  sub     r10, r10, r7           @ cth_Q15[k]*tmpAR+16384-(sth_Q15[k]*ar_g_Q0[k])
+  sub     r10, r10, r7           @ cth_Q15[k - 1]*tmpAR+16384-(sth_Q15[k - 1]*ar_g_Q0[k - 1])
   ssat    r11, #16, r11, asr #15
   ssat    r5, #16, r10, asr #15
-  strh    r11, [r0], #-2         @ Output: ar_g_Q0[k+1]
+  strh    r11, [r0], #-2         @ Output: ar_g_Q0[k]
 
   subs    r9, #1
   bgt     ORDER_COEF_LOOP
diff --git a/webrtc/modules/audio_coding/codecs/isac/fix/source/lattice_c.c b/webrtc/modules/audio_coding/codecs/isac/fix/source/lattice_c.c
index 8c53b0b..43a1579 100644
--- a/webrtc/modules/audio_coding/codecs/isac/fix/source/lattice_c.c
+++ b/webrtc/modules/audio_coding/codecs/isac/fix/source/lattice_c.c
@@ -35,11 +35,13 @@
     int32_t tmp32_2 = 0;
 
     tmpAR = ar_f_Q0[n + 1];
-    for (k = order_coef - 1; k >= 0; k--) {
-      tmp32 = (cth_Q15[k] * tmpAR - sth_Q15[k] * ar_g_Q0[k] + 16384) >> 15;
-      tmp32_2 = (sth_Q15[k] * tmpAR + cth_Q15[k] * ar_g_Q0[k] + 16384) >> 15;
+    for (k = order_coef; k > 0; k--) {
+      tmp32 = (cth_Q15[k - 1] * tmpAR - sth_Q15[k - 1] * ar_g_Q0[k - 1] +
+               16384) >> 15;
+      tmp32_2 = (sth_Q15[k - 1] * tmpAR + cth_Q15[k - 1] * ar_g_Q0[k - 1] +
+                 16384) >> 15;
       tmpAR   = (int16_t)WebRtcSpl_SatW32ToW16(tmp32);
-      ar_g_Q0[k + 1] = (int16_t)WebRtcSpl_SatW32ToW16(tmp32_2);
+      ar_g_Q0[k] = (int16_t)WebRtcSpl_SatW32ToW16(tmp32_2);
     }
     ar_f_Q0[n + 1] = tmpAR;
     ar_g_Q0[0] = tmpAR;
diff --git a/webrtc/modules/audio_coding/codecs/isac/fix/source/pitch_filter.c b/webrtc/modules/audio_coding/codecs/isac/fix/source/pitch_filter.c
index eaf131d..1149d50 100644
--- a/webrtc/modules/audio_coding/codecs/isac/fix/source/pitch_filter.c
+++ b/webrtc/modules/audio_coding/codecs/isac/fix/source/pitch_filter.c
@@ -69,7 +69,6 @@
   int16_t oldLagQ7;
   int16_t oldGainQ12, lagdeltaQ7, curLagQ7, gaindeltaQ12, curGainQ12;
   int indW32 = 0, frcQQ = 0;
-  int32_t tmpW32;
   const int16_t* fracoeffQQ = NULL;
 
   // Assumptions in ARM assembly for WebRtcIsacfix_PitchFilterCoreARM().
@@ -123,8 +122,7 @@
       curGainQ12 += gaindeltaQ12;
       curLagQ7 += lagdeltaQ7;
       indW32 = CalcLrIntQ(curLagQ7, 7);
-      tmpW32 = (indW32 << 7) - curLagQ7;
-      frcQQ = (tmpW32 >> 4) + 4;
+      frcQQ = ((indW32 << 7) + 64 - curLagQ7) >> 4;
 
       if (frcQQ == PITCH_FRACS) {
         frcQQ = 0;
@@ -195,8 +193,7 @@
       // Update parameters for each segment.
       curLagQ7 += lagdeltaQ7;
       indW16 = (int16_t)CalcLrIntQ(curLagQ7, 7);
-      tmpW16 = (indW16 << 7) - curLagQ7;
-      frcQQ = (tmpW16 >> 4) + 4;
+      frcQQ = ((indW16 << 7) + 64 - curLagQ7) >> 4;
 
       if (frcQQ == PITCH_FRACS) {
         frcQQ = 0;
diff --git a/webrtc/modules/audio_coding/codecs/isac/fix/test/isac_speed_test.cc b/webrtc/modules/audio_coding/codecs/isac/fix/test/isac_speed_test.cc
index bb76257..3089f58 100644
--- a/webrtc/modules/audio_coding/codecs/isac/fix/test/isac_speed_test.cc
+++ b/webrtc/modules/audio_coding/codecs/isac/fix/test/isac_speed_test.cc
@@ -65,18 +65,21 @@
   // ISAC takes 10 ms everycall
   const int subblocks = block_duration_ms_ / 10;
   const int subblock_length = 10 * input_sampling_khz_;
-  int value;
+  int value = 0;
 
   clock_t clocks = clock();
   size_t pointer = 0;
   for (int idx = 0; idx < subblocks; idx++, pointer += subblock_length) {
     value = WebRtcIsacfix_Encode(ISACFIX_main_inst_, &in_data[pointer],
                                  bit_stream);
+    if (idx == subblocks - 1)
+      EXPECT_GT(value, 0);
+    else
+      EXPECT_EQ(0, value);
   }
   clocks = clock() - clocks;
-  EXPECT_GT(value, 0);
-  assert(value <= max_bytes);
   *encoded_bytes = value;
+  assert(*encoded_bytes <= max_bytes);
   return 1000.0 * clocks / CLOCKS_PER_SEC;
 }
 
diff --git a/webrtc/modules/audio_coding/codecs/isac/fix/test/kenny.cc b/webrtc/modules/audio_coding/codecs/isac/fix/test/kenny.cc
index bc1a194..ac1efe4 100644
--- a/webrtc/modules/audio_coding/codecs/isac/fix/test/kenny.cc
+++ b/webrtc/modules/audio_coding/codecs/isac/fix/test/kenny.cc
@@ -232,7 +232,7 @@
   CodingMode = 0;
   testNum = 0;
   testCE = 0;
-  for (i = 1; i < argc-2;i++) {
+  for (i = 1; i + 2 < argc; i++) {
     /* Instantaneous mode */
     if (!strcmp ("-I", argv[i])) {
       printf("\nInstantaneous BottleNeck\n");
diff --git a/webrtc/modules/audio_coding/codecs/isac/main/test/ReleaseTest-API/ReleaseTest-API.cc b/webrtc/modules/audio_coding/codecs/isac/main/test/ReleaseTest-API/ReleaseTest-API.cc
index f6bfcdc..496e8c9 100644
--- a/webrtc/modules/audio_coding/codecs/isac/main/test/ReleaseTest-API/ReleaseTest-API.cc
+++ b/webrtc/modules/audio_coding/codecs/isac/main/test/ReleaseTest-API/ReleaseTest-API.cc
@@ -185,7 +185,7 @@
   char transCodingFileName[500];
   int16_t totFileLoop = 0;
   int16_t numFileLoop = 0;
-  for (i = 1; i < argc - 2; i++) {
+  for (i = 1; i + 2 < argc; i++) {
     if (!strcmp("-LOOP", argv[i])) {
       i++;
       totFileLoop = (int16_t)atol(argv[i]);
diff --git a/webrtc/modules/audio_coding/codecs/opus/opus_unittest.cc b/webrtc/modules/audio_coding/codecs/opus/opus_unittest.cc
index 15188a9..bb7bee9 100644
--- a/webrtc/modules/audio_coding/codecs/opus/opus_unittest.cc
+++ b/webrtc/modules/audio_coding/codecs/opus/opus_unittest.cc
@@ -106,6 +106,7 @@
                                     input_audio,
                                     input_samples, kMaxBytes,
                                     bitstream_);
+  EXPECT_GE(encoded_bytes_, 0);
   return WebRtcOpus_Decode(decoder, bitstream_,
                            encoded_bytes_, output_audio,
                            audio_type);
@@ -539,6 +540,7 @@
                                      speech_data_.GetNextBlock(),
                                      kOpus10msFrameSamples, kMaxBytes,
                                      bitstream_);
+  EXPECT_GE(encoded_bytes_, 0);
   EXPECT_EQ(kOpus10msFrameSamples,
             WebRtcOpus_DurationEst(opus_decoder_, bitstream_,
                                    encoded_bytes_));
@@ -548,6 +550,7 @@
                                      speech_data_.GetNextBlock(),
                                      kOpus20msFrameSamples, kMaxBytes,
                                      bitstream_);
+  EXPECT_GE(encoded_bytes_, 0);
   EXPECT_EQ(kOpus20msFrameSamples,
             WebRtcOpus_DurationEst(opus_decoder_, bitstream_,
                                    encoded_bytes_));