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@sl1pkn07
Created November 13, 2023 17:30
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diff --git a/libavcodec/x86/mathops.h b/libavcodec/x86/mathops.h
index 5949dfe..29ea584 100644
--- a/libavcodec/x86/mathops.h
+++ b/libavcodec/x86/mathops.h
@@ -28,10 +28,18 @@
#if ARCH_X86_32
#define MULL(ra, rb, shift) \
({ int rt, dummy; __asm__ (\
+ if (__builtin_constant_p(shift))
"imull %3 \n\t"\
"shrdl %4, %%edx, %%eax \n\t"\
: "=a"(rt), "=d"(dummy)\
- : "a" ((int)(ra)), "rm" ((int)(rb)), "i"(shift));\
+ :"a"(a), "rm"(b), "i"(shift & 0x1F)
+ else
+ __asm__ (
+ "imull %3 \n\t"
+ "shrdl %4, %%edx, %%eax \n\t"
+ :"=a"(rt), "=d"(dummy)
+ :"a"(a), "rm"(b), "c"((uint8_t)shift)
+ );
rt; })
#define MULH(ra, rb) \
@@ -81,19 +89,31 @@ __asm__ volatile(\
// avoid +32 for shift optimization (gcc should do that ...)
#define NEG_SSR32 NEG_SSR32
static inline int32_t NEG_SSR32( int32_t a, int8_t s){
+ if (__builtin_constant_p(s))
__asm__ ("sarl %1, %0\n\t"
: "+r" (a)
- : "ic" ((uint8_t)(-s))
+ : "i" (-s & 0x1F)
);
+ else
+ __asm__ ("sarl %1, %0\n\t"
+ : "+r" (a)
+ : "c" ((uint8_t)(-s))
+ );
return a;
}
#define NEG_USR32 NEG_USR32
static inline uint32_t NEG_USR32(uint32_t a, int8_t s){
+ if (__builtin_constant_p(s))
__asm__ ("shrl %1, %0\n\t"
: "+r" (a)
- : "ic" ((uint8_t)(-s))
+ : "i" (-s & 0x1F)
);
+ else
+ __asm__ ("shrl %1, %0\n\t"
+ : "+r" (a)
+ : "c" ((uint8_t)(-s))
+ );
return a;
}
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