Merge commit '982b596e'

* commit '982b596e':
  h264: avoid undefined behavior in chroma motion compensation
Merged-by: Michael Niedermayer <michaelni@gmx.at>

libavcodec/h264chroma_template.c

@@ -42,7 +42,7 @@ static void FUNCC(OPNAME ## h264_chroma_mc1)(uint8_t *_dst/*align 8*/, uint8_t *
             dst+= stride;\
             src+= stride;\
         }\
-    }else{\
+    } else if (B + C) {\
         const int E= B+C;\
         const int step= C ? stride : 1;\
         for(i=0; i<h; i++){\
@@ -50,6 +50,12 @@ static void FUNCC(OPNAME ## h264_chroma_mc1)(uint8_t *_dst/*align 8*/, uint8_t *
             dst+= stride;\
             src+= stride;\
         }\
+    } else {\
+        for(i=0; i<h; i++){\
+            OP(dst[0], (A*src[0]));\
+            dst+= stride;\
+            src+= stride;\
+        }\
     }\
 }\
 static void FUNCC(OPNAME ## h264_chroma_mc2)(uint8_t *_dst/*align 8*/, uint8_t *_src/*align 1*/, int stride, int h, int x, int y){\
@@ -71,7 +77,7 @@ static void FUNCC(OPNAME ## h264_chroma_mc2)(uint8_t *_dst/*align 8*/, uint8_t *
             dst+= stride;\
             src+= stride;\
         }\
-    }else{\
+    } else if (B + C) {\
         const int E= B+C;\
         const int step= C ? stride : 1;\
         for(i=0; i<h; i++){\
@@ -80,6 +86,13 @@ static void FUNCC(OPNAME ## h264_chroma_mc2)(uint8_t *_dst/*align 8*/, uint8_t *
             dst+= stride;\
             src+= stride;\
         }\
+    } else {\
+        for ( i = 0; i < h; i++){\
+            OP(dst[0], A * src[0]);\
+            OP(dst[1], A * src[1]);\
+            dst += stride;\
+            src += stride;\
+        }\
     }\
 }\
 \
@@ -104,7 +117,7 @@ static void FUNCC(OPNAME ## h264_chroma_mc4)(uint8_t *_dst/*align 8*/, uint8_t *
             dst+= stride;\
             src+= stride;\
         }\
-    }else{\
+    } else if (B + C) {\
         const int E= B+C;\
         const int step= C ? stride : 1;\
         for(i=0; i<h; i++){\
@@ -115,6 +128,15 @@ static void FUNCC(OPNAME ## h264_chroma_mc4)(uint8_t *_dst/*align 8*/, uint8_t *
             dst+= stride;\
             src+= stride;\
         }\
+    } else {\
+        for ( i = 0; i < h; i++){\
+            OP(dst[0], A * src[0]);\
+            OP(dst[1], A * src[1]);\
+            OP(dst[2], A * src[2]);\
+            OP(dst[3], A * src[3]);\
+            dst += stride;\
+            src += stride;\
+        }\
     }\
 }\
 \
@@ -143,7 +165,7 @@ static void FUNCC(OPNAME ## h264_chroma_mc8)(uint8_t *_dst/*align 8*/, uint8_t *
             dst+= stride;\
             src+= stride;\
         }\
-    }else{\
+    } else if (B + C) {\
         const int E= B+C;\
         const int step= C ? stride : 1;\
         for(i=0; i<h; i++){\
@@ -158,6 +180,19 @@ static void FUNCC(OPNAME ## h264_chroma_mc8)(uint8_t *_dst/*align 8*/, uint8_t *
             dst+= stride;\
             src+= stride;\
         }\
+    } else {\
+        for ( i = 0; i < h; i++){\
+            OP(dst[0], A * src[0]);\
+            OP(dst[1], A * src[1]);\
+            OP(dst[2], A * src[2]);\
+            OP(dst[3], A * src[3]);\
+            OP(dst[4], A * src[4]);\
+            OP(dst[5], A * src[5]);\
+            OP(dst[6], A * src[6]);\
+            OP(dst[7], A * src[7]);\
+            dst += stride;\
+            src += stride;\
+        }\
     }\
 }