mathops: convert MULL/MULH/MUL64 to inline functions rather than macros.

This fixes unexpected name collisions that were occurring with variables
declared within the macros.
It also fixes the fate-acodec-ac3_fixed regression test on x86-32.

libavcodec/x86/mathops.h

@@ -26,24 +26,45 @@
 #include "libavutil/common.h"
 
 #if ARCH_X86_32
-#define MULL(ra, rb, shift) \
-        ({ int rt, dummy; __asm__ (\
-            "imull %3               \n\t"\
-            "shrdl %4, %%edx, %%eax \n\t"\
-            : "=a"(rt), "=d"(dummy)\
-            : "a" ((int)(ra)), "rm" ((int)(rb)), "i"(shift));\
-         rt; })
 
-#define MULH(ra, rb) \
-    ({ int rt, dummy;\
-     __asm__ ("imull %3\n\t" : "=d"(rt), "=a"(dummy): "a" ((int)(ra)), "rm" ((int)(rb)));\
-     rt; })
+#define MULL MULL
+static av_always_inline av_const int MULL(int a, int b, unsigned shift)
+{
+    int rt, dummy;
+    __asm__ (
+        "imull %3               \n\t"
+        "shrdl %4, %%edx, %%eax \n\t"
+        :"=a"(rt), "=d"(dummy)
+        :"a"(a), "rm"(b), "i"(shift)
+    );
+    return rt;
+}
 
-#define MUL64(ra, rb) \
-    ({ int64_t rt;\
-     __asm__ ("imull %2\n\t" : "=A"(rt) : "a" ((int)(ra)), "g" ((int)(rb)));\
-     rt; })
-#endif
+#define MULH MULH
+static av_always_inline av_const int MULH(int a, int b)
+{
+    int rt, dummy;
+    __asm__ (
+        "imull %3"
+        :"=d"(rt), "=a"(dummy)
+        :"a"(a), "rm"(b)
+    );
+    return rt;
+}
+
+#define MUL64 MUL64
+static av_always_inline av_const int64_t MUL64(int a, int b)
+{
+    int64_t rt;
+    __asm__ (
+        "imull %2"
+        :"=A"(rt)
+        :"a"(a), "g"(b)
+    );
+    return rt;
+}
+
+#endif /* ARCH_X86_32 */
 
 #if HAVE_CMOV
 /* median of 3 */