commit 05f3ec1356aa2dc924d8366bd94a0eef0666c30f
author kwiberg <kwiberg@webrtc.org> Fri Oct 07 07:38:48 2016 -0700
committer Commit bot <commit-bot@chromium.org> Fri Oct 07 14:38:54 2016 +0000
tree 173e0770610ab491e55104007fac294195cfe73e
parent d2cf1ce8aacc343c4bf4a01c60dda581a7a748be

Fix "left shift of negative value" bug

The values in question are supposed to be able to be negative.

BUG=chromium:653448

Review-Url: https://codereview.webrtc.org/2387333005
Cr-Commit-Position: refs/heads/master@{#14573}

webrtc/common_audio/signal_processing/filter_ar.c

diff --git a/webrtc/common_audio/signal_processing/filter_ar.c b/webrtc/common_audio/signal_processing/filter_ar.c
index dfbc4c2..d389ee4 100644
--- a/webrtc/common_audio/signal_processing/filter_ar.c
+++ b/webrtc/common_audio/signal_processing/filter_ar.c
@@ -45,7 +45,7 @@
         int16_t* state_ptr = &state[state_length - 1];
         int16_t* state_low_ptr = &state_low[state_length - 1];
 
-        o = (int32_t)(*x_ptr++) << 12;
+        o = (int32_t)(*x_ptr++) * (1 << 12);
         oLOW = (int32_t)0;
 
         stop = (i < a_length) ? i + 1 : a_length;
@@ -62,8 +62,8 @@
 
         o += (oLOW >> 12);
         *filteredFINAL_ptr = (int16_t)((o + (int32_t)2048) >> 12);
-        *filteredFINAL_LOW_ptr++ = (int16_t)(o - ((int32_t)(*filteredFINAL_ptr++)
-                << 12));
+        *filteredFINAL_LOW_ptr++ =
+            (int16_t)(o - ((int32_t)(*filteredFINAL_ptr++) * (1 << 12)));
     }
 
     // Save the filter state