diff options
Diffstat (limited to 'silk/arm/macros_armv4.h')
| -rw-r--r-- | silk/arm/macros_armv4.h | 13 |
1 files changed, 10 insertions, 3 deletions
diff --git a/silk/arm/macros_armv4.h b/silk/arm/macros_armv4.h index 3f30e972..877eb18d 100644 --- a/silk/arm/macros_armv4.h +++ b/silk/arm/macros_armv4.h @@ -28,6 +28,11 @@ POSSIBILITY OF SUCH DAMAGE. #ifndef SILK_MACROS_ARMv4_H #define SILK_MACROS_ARMv4_H +/* This macro only avoids the undefined behaviour from a left shift of + a negative value. It should only be used in macros that can't include + SigProc_FIX.h. In other cases, use silk_LSHIFT32(). */ +#define SAFE_SHL(a,b) ((opus_int32)((opus_uint32)(a) << (b))) + /* (a32 * (opus_int32)((opus_int16)(b32))) >> 16 output have to be 32bit int */ #undef silk_SMULWB static OPUS_INLINE opus_int32 silk_SMULWB_armv4(opus_int32 a, opus_int16 b) @@ -38,7 +43,7 @@ static OPUS_INLINE opus_int32 silk_SMULWB_armv4(opus_int32 a, opus_int16 b) "#silk_SMULWB\n\t" "smull %0, %1, %2, %3\n\t" : "=&r"(rd_lo), "=&r"(rd_hi) - : "%r"(a), "r"(b<<16) + : "%r"(a), "r"(SAFE_SHL(b,16)) ); return rd_hi; } @@ -80,7 +85,7 @@ static OPUS_INLINE opus_int32 silk_SMULWW_armv4(opus_int32 a, opus_int32 b) : "=&r"(rd_lo), "=&r"(rd_hi) : "%r"(a), "r"(b) ); - return (rd_hi<<16)+(rd_lo>>16); + return SAFE_SHL(rd_hi,16)+(rd_lo>>16); } #define silk_SMULWW(a, b) (silk_SMULWW_armv4(a, b)) @@ -96,8 +101,10 @@ static OPUS_INLINE opus_int32 silk_SMLAWW_armv4(opus_int32 a, opus_int32 b, : "=&r"(rd_lo), "=&r"(rd_hi) : "%r"(b), "r"(c) ); - return a+(rd_hi<<16)+(rd_lo>>16); + return a+SAFE_SHL(rd_hi,16)+(rd_lo>>16); } #define silk_SMLAWW(a, b, c) (silk_SMLAWW_armv4(a, b, c)) +#undef SAFE_SHL + #endif /* SILK_MACROS_ARMv4_H */ |