The extract signed single bitfield produces significantly smaller code on x86_64.
Signed-off-by: Richard Henderson <r...@twiddle.net> --- target-alpha/int_helper.c | 30 ++++++++++++------------------ 1 file changed, 12 insertions(+), 18 deletions(-) diff --git a/target-alpha/int_helper.c b/target-alpha/int_helper.c index 8e4537f..c023fa1 100644 --- a/target-alpha/int_helper.c +++ b/target-alpha/int_helper.c @@ -37,31 +37,25 @@ uint64_t helper_cttz(uint64_t arg) return ctz64(arg); } -static inline uint64_t byte_zap(uint64_t op, uint8_t mskb) +uint64_t helper_zapnot(uint64_t val, uint64_t mskb) { uint64_t mask; - mask = 0; - mask |= ((mskb >> 0) & 1) * 0x00000000000000FFULL; - mask |= ((mskb >> 1) & 1) * 0x000000000000FF00ULL; - mask |= ((mskb >> 2) & 1) * 0x0000000000FF0000ULL; - mask |= ((mskb >> 3) & 1) * 0x00000000FF000000ULL; - mask |= ((mskb >> 4) & 1) * 0x000000FF00000000ULL; - mask |= ((mskb >> 5) & 1) * 0x0000FF0000000000ULL; - mask |= ((mskb >> 6) & 1) * 0x00FF000000000000ULL; - mask |= ((mskb >> 7) & 1) * 0xFF00000000000000ULL; - - return op & ~mask; -} + mask = sextract64(mskb, 0, 1) & 0x00000000000000fful; + mask |= sextract64(mskb, 1, 1) & 0x000000000000ff00ul; + mask |= sextract64(mskb, 2, 1) & 0x0000000000ff0000ul; + mask |= sextract64(mskb, 3, 1) & 0x00000000ff000000ul; + mask |= sextract64(mskb, 4, 1) & 0x000000ff00000000ul; + mask |= sextract64(mskb, 5, 1) & 0x0000ff0000000000ul; + mask |= sextract64(mskb, 6, 1) & 0x00ff000000000000ul; + mask |= sextract64(mskb, 7, 1) & 0xff00000000000000ul; -uint64_t helper_zap(uint64_t val, uint64_t mask) -{ - return byte_zap(val, mask); + return val & mask; } -uint64_t helper_zapnot(uint64_t val, uint64_t mask) +uint64_t helper_zap(uint64_t val, uint64_t mask) { - return byte_zap(val, ~mask); + return helper_zapnot(val, ~mask); } uint64_t helper_cmpbge(uint64_t op1, uint64_t op2) -- 2.1.0