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authorUlrich Drepper <drepper@redhat.com>1998-05-06 14:43:15 +0000
committerUlrich Drepper <drepper@redhat.com>1998-05-06 14:43:15 +0000
commit6600049466b586e3decaf24bd70c06b21382cf98 (patch)
tree536fc5c8efe78035527223283bcd5a48ac259576 /sysdeps/libm-ieee754
parentb22fc5f5651706304ac09305ac3ee5bf84516378 (diff)
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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')
-rw-r--r--sysdeps/libm-ieee754/e_exp.c48
-rw-r--r--sysdeps/libm-ieee754/e_expf.c48
-rw-r--r--sysdeps/libm-ieee754/s_exp2.c14
-rw-r--r--sysdeps/libm-ieee754/s_exp2f.c14
4 files changed, 36 insertions, 88 deletions
diff --git a/sysdeps/libm-ieee754/e_exp.c b/sysdeps/libm-ieee754/e_exp.c
index 660c5bc88d..5eae12a19c 100644
--- a/sysdeps/libm-ieee754/e_exp.c
+++ b/sysdeps/libm-ieee754/e_exp.c
@@ -76,8 +76,8 @@ __ieee754_exp (double x)
/* Check for usual case. */
if (isless (x, himark) && isgreater (x, lomark))
{
- static const double TWO43 = 8796093022208.0;
- static const double TWO52 = 4503599627370496.0;
+ static const double THREEp42 = 13194139533312.0;
+ static const double THREEp51 = 6755399441055744.0;
/* 1/ln(2). */
static const double M_1_LN2 = 1.442695040888963387;
/* ln(2), part 1 */
@@ -94,40 +94,22 @@ __ieee754_exp (double x)
fesetround (FE_TONEAREST);
/* Calculate n. */
- if (x >= 0)
- {
- n = x * M_1_LN2 + TWO52;
- n -= TWO52;
- }
- else
- {
- n = x * M_1_LN2 - TWO52;
- n += TWO52;
- }
+ n = x * M_1_LN2 + THREEp51;
+ n -= THREEp51;
x = x - n*M_LN2_0;
- if (x >= 0)
- {
- /* Calculate t/512. */
- t = x + TWO43;
- t -= TWO43;
- x -= t;
-
- /* Compute tval = t. */
- tval = (int) (t * 512.0);
-
- x -= __exp_deltatable[tval];
- }
- else
- {
- /* As above, but x is negative. */
- t = x - TWO43;
- t += TWO43;
- x -= t;
- tval = (int) (t * 512.0);
+ /* Calculate t/512. */
+ t = x + THREEp42;
+ t -= THREEp42;
+ x -= t;
- x += __exp_deltatable[-tval];
- }
+ /* Compute tval = t. */
+ tval = (int) (t * 512.0);
+
+ if (t >= 0)
+ x -= __exp_deltatable[tval];
+ else
+ x += __exp_deltatable[-tval];
/* Now, the variable x contains x + n*ln(2)_1. */
dely = n*M_LN2_1;
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];
diff --git a/sysdeps/libm-ieee754/s_exp2.c b/sysdeps/libm-ieee754/s_exp2.c
index ead1ce89eb..875d4d6f2c 100644
--- a/sysdeps/libm-ieee754/s_exp2.c
+++ b/sysdeps/libm-ieee754/s_exp2.c
@@ -48,7 +48,7 @@ __ieee754_exp2 (double x)
/* Check for usual case. */
if (isless (x, himark) && isgreater (x, lomark))
{
- static const double TWO43 = 8796093022208.0;
+ static const double THREEp42 = 13194139533312.0;
int tval, unsafe;
double rx, x22, result;
union ieee754_double ex2_u, scale_u;
@@ -66,16 +66,8 @@ __ieee754_exp2 (double x)
x = ex + t/512 + x1.
First, calculate rx = ex + t/512. */
- if (x >= 0)
- {
- rx = x + TWO43;
- rx -= TWO43;
- }
- else
- {
- rx = x - TWO43;
- rx += TWO43;
- }
+ rx = x + THREEp42;
+ rx -= THREEp42;
x -= rx; /* Compute x=x1. */
/* Compute tval = (ex*512 + t)+256.
Now, t = (tval mod 512)-256 and ex=tval/512 [that's mod, NOT %; and
diff --git a/sysdeps/libm-ieee754/s_exp2f.c b/sysdeps/libm-ieee754/s_exp2f.c
index 641b7548f1..8229885453 100644
--- a/sysdeps/libm-ieee754/s_exp2f.c
+++ b/sysdeps/libm-ieee754/s_exp2f.c
@@ -49,7 +49,7 @@ __ieee754_exp2f (float x)
/* Check for usual case. */
if (isless (x, himark) && isgreater (x, lomark))
{
- static const float TWO15 = 32768.0;
+ static const float THREEp14 = 49152.0;
int tval, unsafe;
float rx, x22, result;
union ieee754_float ex2_u, scale_u;
@@ -67,16 +67,8 @@ __ieee754_exp2f (float x)
x = ex + t/512 + x1.
First, calculate rx = ex + t/256. */
- if (x >= 0)
- {
- rx = x + TWO15;
- rx -= TWO15;
- }
- else
- {
- rx = x - TWO15;
- rx += TWO15;
- }
+ rx = x + THREEp14;
+ rx -= THREEp14;
x -= rx; /* Compute x=x1. */
/* Compute tval = (ex*256 + t)+128.
Now, t = (tval mod 256)-128 and ex=tval/256 [that's mod, NOT %; and