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authorUlrich Drepper <drepper@gmail.com>2012-01-09 18:59:04 -0500
committerUlrich Drepper <drepper@gmail.com>2012-01-09 18:59:04 -0500
commitd6e97a1da05c1be8ac4cc2f735a98181c457d90b (patch)
treef0982c62e9e7e2bade0dfb87796c36aa0011f066
parente5f484c622fa0163379b7e577d5b289f0a0b49e7 (diff)
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Some branch prediction for log1p
-rw-r--r--ChangeLog4
-rw-r--r--sysdeps/ieee754/dbl-64/s_log1p.c6
2 files changed, 7 insertions, 3 deletions
diff --git a/ChangeLog b/ChangeLog
index 2035826..07fd067 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,7 @@
+2012-01-09 Ulrich Drepper <drepper@gmail.com>
+
+ * sysdeps/ieee754/dbl-64/s_log1p.c (__log1p): Add branch prediction.
+
2012-01-08 Ulrich Drepper <drepper@gmail.com>
* io/bits/poll2.h: Add __BEGIN/__END_DECLS.
diff --git a/sysdeps/ieee754/dbl-64/s_log1p.c b/sysdeps/ieee754/dbl-64/s_log1p.c
index dc79a02..f82048f 100644
--- a/sysdeps/ieee754/dbl-64/s_log1p.c
+++ b/sysdeps/ieee754/dbl-64/s_log1p.c
@@ -106,11 +106,11 @@ __log1p(double x)
k = 1;
if (hx < 0x3FDA827A) { /* x < 0.41422 */
- if(ax>=0x3ff00000) { /* x <= -1.0 */
+ if(__builtin_expect(ax>=0x3ff00000, 0)) { /* x <= -1.0 */
if(x==-1.0) return -two54/(x-x);/* log1p(-1)=+inf */
else return (x-x)/(x-x); /* log1p(x<-1)=NaN */
}
- if(ax<0x3e200000) { /* |x| < 2**-29 */
+ if(__builtin_expect(ax<0x3e200000, 0)) { /* |x| < 2**-29 */
math_force_eval(two54+x); /* raise inexact */
if (ax<0x3c900000) /* |x| < 2**-54 */
return x;
@@ -120,7 +120,7 @@ __log1p(double x)
if(hx>0||hx<=((int32_t)0xbfd2bec3)) {
k=0;f=x;hu=1;} /* -0.2929<x<0.41422 */
}
- if (hx >= 0x7ff00000) return x+x;
+ else if (__builtin_expect(hx >= 0x7ff00000, 0)) return x+x;
if(k!=0) {
if(hx<0x43400000) {
u = 1.0+x;