diff options
| author | Szabolcs Nagy <nsz@port70.net> | 2017-10-22 18:06:00 +0000 |
|---|---|---|
| committer | Rich Felker <dalias@aerifal.cx> | 2019-04-17 23:43:53 -0400 |
| commit | 3f94c648ef32c95fa7f5c94b5cb8f2b764fc1938 (patch) | |
| tree | 078300c87fed8d8e673f1b94ef4e6bad95cf587a /src/internal | |
| parent | 098868b338e9afd3ef844070a94b9b10360d913f (diff) | |
| download | musl-3f94c648ef32c95fa7f5c94b5cb8f2b764fc1938.tar.gz | |
math: new exp2f and expf
from https://github.com/ARM-software/optimized-routines,
commit 04884bd04eac4b251da4026900010ea7d8850edc
In expf TOINT_INTRINSICS is kept, but is unused, it would require support
for __builtin_round and __builtin_lround as single instruction.
code size change: +94 bytes.
benchmark on x86_64 before, after, speedup:
-Os:
expf rthruput: 9.19 ns/call 8.11 ns/call 1.13x
expf latency: 34.19 ns/call 18.77 ns/call 1.82x
exp2f rthruput: 5.59 ns/call 6.52 ns/call 0.86x
exp2f latency: 17.93 ns/call 16.70 ns/call 1.07x
-O3:
expf rthruput: 9.12 ns/call 4.92 ns/call 1.85x
expf latency: 34.44 ns/call 18.99 ns/call 1.81x
exp2f rthruput: 5.58 ns/call 4.49 ns/call 1.24x
exp2f latency: 17.95 ns/call 16.94 ns/call 1.06x
Diffstat (limited to 'src/internal')
| -rw-r--r-- | src/internal/libm.h | 16 |
1 files changed, 16 insertions, 0 deletions
diff --git a/src/internal/libm.h b/src/internal/libm.h index 5212bab1..98bf5c68 100644 --- a/src/internal/libm.h +++ b/src/internal/libm.h @@ -64,6 +64,22 @@ union ldshape { /* Support signaling NaNs. */ #define WANT_SNAN 0 +#ifndef TOINT_INTRINSICS +#define TOINT_INTRINSICS 0 +#endif + +#if TOINT_INTRINSICS +/* Round x to nearest int in all rounding modes, ties have to be rounded + consistently with converttoint so the results match. If the result + would be outside of [-2^31, 2^31-1] then the semantics is unspecified. */ +static double_t roundtoint(double_t); + +/* Convert x to nearest int in all rounding modes, ties have to be rounded + consistently with roundtoint. If the result is not representible in an + int32_t then the semantics is unspecified. */ +static int32_t converttoint(double_t); +#endif + /* Helps static branch prediction so hot path can be better optimized. */ #ifdef __GNUC__ #define predict_true(x) __builtin_expect(!!(x), 1) |