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authorVineet Gupta <vgupta@synopsys.com>2020-05-29 15:21:39 -0700
committerVineet Gupta <vgupta@synopsys.com>2020-06-03 10:23:22 -0700
commit3374868668e708581ca06e256f6122518c89a8ad (patch)
tree597e6a659674c190f2f388fa9f5e58b5c7cc0dfb /sysdeps
parentba9f6ee9bb8a894c9e2fb715edf693dd157b420a (diff)
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ieee754: provide gcc builtins based generic sqrt functions
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Diffstat (limited to 'sysdeps')
-rw-r--r--sysdeps/generic/math-use-builtins.h3
-rw-r--r--sysdeps/ieee754/dbl-64/e_sqrt.c6
-rw-r--r--sysdeps/ieee754/flt-32/e_sqrtf.c16
-rw-r--r--sysdeps/s390/fpu/math-use-builtins.h3
4 files changed, 22 insertions, 6 deletions
diff --git a/sysdeps/generic/math-use-builtins.h b/sysdeps/generic/math-use-builtins.h
index 8a39ef5..fc724c8 100644
--- a/sysdeps/generic/math-use-builtins.h
+++ b/sysdeps/generic/math-use-builtins.h
@@ -60,4 +60,7 @@
# define USE_COPYSIGNF128_BUILTIN 0
#endif
+#define USE_SQRT_BUILTIN 0
+#define USE_SQRTF_BUILTIN 0
+
#endif /* math-use-builtins.h */
diff --git a/sysdeps/ieee754/dbl-64/e_sqrt.c b/sysdeps/ieee754/dbl-64/e_sqrt.c
index d42a1a4..518a8ae 100644
--- a/sysdeps/ieee754/dbl-64/e_sqrt.c
+++ b/sysdeps/ieee754/dbl-64/e_sqrt.c
@@ -41,6 +41,7 @@
#include <math_private.h>
#include <fenv_private.h>
#include <libm-alias-finite.h>
+#include <math-use-builtins.h>
/*********************************************************************/
/* An ultimate sqrt routine. Given an IEEE double machine number x */
@@ -50,6 +51,10 @@
double
__ieee754_sqrt (double x)
{
+#if USE_SQRT_BUILTIN
+ return __builtin_sqrt (x);
+#else
+ /* Use generic implementation. */
static const double
rt0 = 9.99999999859990725855365213134618E-01,
rt1 = 4.99999999495955425917856814202739E-01,
@@ -138,6 +143,7 @@ __ieee754_sqrt (double x)
return (x - x) / (x - x); /* sqrt(-ve)=sNaN */
return 0x1p-256 * __ieee754_sqrt (x * 0x1p512);
}
+#endif /* ! USE_SQRT_BUILTIN */
}
#ifndef __ieee754_sqrt
libm_alias_finite (__ieee754_sqrt, __sqrt)
diff --git a/sysdeps/ieee754/flt-32/e_sqrtf.c b/sysdeps/ieee754/flt-32/e_sqrtf.c
index b339444..177bf5d 100644
--- a/sysdeps/ieee754/flt-32/e_sqrtf.c
+++ b/sysdeps/ieee754/flt-32/e_sqrtf.c
@@ -16,12 +16,15 @@
#include <math.h>
#include <math_private.h>
#include <libm-alias-finite.h>
-
-static const float one = 1.0, tiny=1.0e-30;
+#include <math-use-builtins.h>
float
__ieee754_sqrtf(float x)
{
+#if USE_SQRTF_BUILTIN
+ return __builtin_sqrtf (x);
+#else
+ /* Use generic implementation. */
float z;
int32_t sign = (int)0x80000000;
int32_t ix,s,q,m,t,i;
@@ -70,10 +73,10 @@ __ieee754_sqrtf(float x)
/* use floating add to find out rounding direction */
if(ix!=0) {
- z = one-tiny; /* trigger inexact flag */
- if (z>=one) {
- z = one+tiny;
- if (z>one)
+ z = 0x1p0 - 0x1.4484cp-100; /* trigger inexact flag. */
+ if (z >= 0x1p0) {
+ z = 0x1p0 + 0x1.4484cp-100;
+ if (z > 0x1p0)
q += 2;
else
q += (q&1);
@@ -83,6 +86,7 @@ __ieee754_sqrtf(float x)
ix += (m <<23);
SET_FLOAT_WORD(z,ix);
return z;
+#endif /* ! USE_SQRTF_BUILTIN */
}
#ifndef __ieee754_sqrtf
libm_alias_finite (__ieee754_sqrtf, __sqrtf)
diff --git a/sysdeps/s390/fpu/math-use-builtins.h b/sysdeps/s390/fpu/math-use-builtins.h
index db00c3a..eb87b6b 100644
--- a/sysdeps/s390/fpu/math-use-builtins.h
+++ b/sysdeps/s390/fpu/math-use-builtins.h
@@ -108,4 +108,7 @@
# define USE_COPYSIGNF128_BUILTIN 0
#endif
+#define USE_SQRT_BUILTIN 0
+#define USE_SQRTF_BUILTIN 0
+
#endif /* math-use-builtins.h */