diff options
author | Ulrich Drepper <drepper@redhat.com> | 1998-05-06 14:43:15 +0000 |
---|---|---|
committer | Ulrich Drepper <drepper@redhat.com> | 1998-05-06 14:43:15 +0000 |
commit | 6600049466b586e3decaf24bd70c06b21382cf98 (patch) | |
tree | 536fc5c8efe78035527223283bcd5a48ac259576 /sysdeps/libm-ieee754/e_expf.c | |
parent | b22fc5f5651706304ac09305ac3ee5bf84516378 (diff) | |
download | glibc-6600049466b586e3decaf24bd70c06b21382cf98.tar glibc-6600049466b586e3decaf24bd70c06b21382cf98.tar.gz glibc-6600049466b586e3decaf24bd70c06b21382cf98.tar.bz2 glibc-6600049466b586e3decaf24bd70c06b21382cf98.zip |
Update.
1998-04-16 07:42 Geoff Keating <geoffk@ozemail.com.au>
* Makeconfig [!build-static]: Link `static' binaries with libc_pic.a.
Still need *FLAGS-.o because we still sometimes build .o files.
* db2/Makefile: Don't build libndbm.a if !build-static.
1998-04-16 07:42 Geoff Keating <geoffk@ozemail.com.au>
* configure.in: New test for broken gcc on PowerPC.
* sysdeps/powerpc/atomicity.h: Use result of test.
* linuxthreads/sysdeps/powerpc/pt-machine.h: Use result of test.
* math/libm-test.c: Update many of the epsilon to match actual
performance.
* sysdeps/libm-ieee754/e_exp.c: Reduce the number of branches.
* sysdeps/libm-ieee754/e_expf.c: Likewise.
* sysdeps/libm-ieee754/s_exp2.c: Likewise.
* sysdeps/libm-ieee754/s_exp2f.c: Likewise.
* sysdeps/libm-ieee754/e_pow.c: Correct typo.
* sysdeps/powerpc/elf/libc-start.c: New file.
* sysdeps/powerpc/elf/start.S: New file, use libc-start.
* sysdeps/powerpc/elf/start.c: Delete.
* sysdeps/unix/sysv/linux/powerpc/Dist: Remove syscall.h
* sysdeps/unix/sysv/linux/powerpc/syscall.h: Delete. It was unused.
* sysdeps/unix/sysv/linux/powerpc/dl-sysdep.c: Correct previous
few patches.
Diffstat (limited to 'sysdeps/libm-ieee754/e_expf.c')
-rw-r--r-- | sysdeps/libm-ieee754/e_expf.c | 48 |
1 files changed, 15 insertions, 33 deletions
diff --git a/sysdeps/libm-ieee754/e_expf.c b/sysdeps/libm-ieee754/e_expf.c index c4a7b644fd..ff6357bd1d 100644 --- a/sysdeps/libm-ieee754/e_expf.c +++ b/sysdeps/libm-ieee754/e_expf.c @@ -71,8 +71,8 @@ __ieee754_expf (float x) /* Check for usual case. */ if (isless (x, himark) && isgreater (x, lomark)) { - static const float TWO43 = 8796093022208.0; - static const float TWO23 = 8388608.0; + static const float THREEp42 = 13194139533312.0; + static const float THREEp22 = 12582912.0; /* 1/ln(2). */ #undef M_1_LN2 static const float M_1_LN2 = 1.44269502163f; @@ -90,40 +90,22 @@ __ieee754_expf (float x) fesetround (FE_TONEAREST); /* Calculate n. */ - if (x >= 0) - { - n = x * M_1_LN2 + TWO23; - n -= TWO23; - } - else - { - n = x * M_1_LN2 - TWO23; - n += TWO23; - } + n = x * M_1_LN2 + THREEp22; + n -= THREEp22; dx = x - n*M_LN2; - if (dx >= 0) - { - /* Calculate t/512. */ - t = dx + TWO43; - t -= TWO43; - dx -= t; - - /* Compute tval = t. */ - tval = (int) (t * 512.0); - - delta = - __exp_deltatable[tval]; - } - else - { - /* As above, but x is negative. */ - t = dx - TWO43; - t += TWO43; - dx -= t; - tval = (int) (t * 512.0); + /* Calculate t/512. */ + t = dx + THREEp42; + t -= THREEp42; + dx -= t; - delta = __exp_deltatable[-tval]; - } + /* Compute tval = t. */ + tval = (int) (t * 512.0); + + if (t >= 0) + delta = - __exp_deltatable[tval]; + else + delta = __exp_deltatable[-tval]; /* Compute ex2 = 2^n e^(t/512+delta[t]). */ ex2_u.d = __exp_atable[tval+177]; |