[PATCH v3 2/4] iee754: provide gcc builtins based generic fma functions
Vineet Gupta
Vineet.Gupta1@synopsys.com
Tue Jun 2 21:32:18 GMT 2020
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
---
sysdeps/generic/math-use-builtins.h | 5 +++++
sysdeps/ieee754/dbl-64/s_fma.c | 6 ++++++
sysdeps/ieee754/dbl-64/s_fmaf.c | 6 ++++++
sysdeps/ieee754/float128/float128_private.h | 2 ++
sysdeps/ieee754/ldbl-128/s_fma.c | 5 +++++
sysdeps/ieee754/ldbl-128/s_fmal.c | 5 +++++
sysdeps/s390/fpu/math-use-builtins.h | 5 +++++
7 files changed, 34 insertions(+)
diff --git a/sysdeps/generic/math-use-builtins.h b/sysdeps/generic/math-use-builtins.h
index fc724c824a17..cf25ed8a2138 100644
--- a/sysdeps/generic/math-use-builtins.h
+++ b/sysdeps/generic/math-use-builtins.h
@@ -63,4 +63,9 @@
#define USE_SQRT_BUILTIN 0
#define USE_SQRTF_BUILTIN 0
+#define USE_FMA_BUILTIN 0
+#define USE_FMAF_BUILTIN 0
+#define USE_FMAL_BUILTIN 0
+#define USE_FMAF128_BUILTIN 0
+
#endif /* math-use-builtins.h */
diff --git a/sysdeps/ieee754/dbl-64/s_fma.c b/sysdeps/ieee754/dbl-64/s_fma.c
index 876df6e78bdc..9dc5b132b9ee 100644
--- a/sysdeps/ieee754/dbl-64/s_fma.c
+++ b/sysdeps/ieee754/dbl-64/s_fma.c
@@ -25,6 +25,7 @@
#include <fenv_private.h>
#include <libm-alias-double.h>
#include <tininess.h>
+#include <math-use-builtins.h>
/* This implementation uses rounding to odd to avoid problems with
double rounding. See a paper by Boldo and Melquiond:
@@ -33,6 +34,10 @@
double
__fma (double x, double y, double z)
{
+#if USE_FMA_BUILTIN
+ return __builtin_fma (x, y, z);
+#else
+ /* Use generic implementation. */
union ieee754_double u, v, w;
int adjust = 0;
u.d = x;
@@ -292,6 +297,7 @@ __fma (double x, double y, double z)
v.ieee.mantissa1 |= j;
return v.d * 0x1p-108;
}
+#endif /* ! USE_FMA_BUILTIN */
}
#ifndef __fma
libm_alias_double (__fma, fma)
diff --git a/sysdeps/ieee754/dbl-64/s_fmaf.c b/sysdeps/ieee754/dbl-64/s_fmaf.c
index 57329d0a87fe..93b8660d5242 100644
--- a/sysdeps/ieee754/dbl-64/s_fmaf.c
+++ b/sysdeps/ieee754/dbl-64/s_fmaf.c
@@ -23,6 +23,7 @@
#include <math-barriers.h>
#include <fenv_private.h>
#include <libm-alias-float.h>
+#include <math-use-builtins.h>
/* This implementation relies on double being more than twice as
precise as float and uses rounding to odd in order to avoid problems
@@ -33,6 +34,10 @@
float
__fmaf (float x, float y, float z)
{
+#if USE_FMAF_BUILTIN
+ return __builtin_fmaf (x, y, z);
+#else
+ /* Use generic implementation. */
fenv_t env;
/* Multiplication is always exact. */
@@ -60,6 +65,7 @@ __fmaf (float x, float y, float z)
/* And finally truncation with round to nearest. */
return (float) u.d;
+#endif /* ! USE_FMAF_BUILTIN */
}
#ifndef __fmaf
libm_alias_float (__fma, fma)
diff --git a/sysdeps/ieee754/float128/float128_private.h b/sysdeps/ieee754/float128/float128_private.h
index f97463d9dc1b..ab6fc9f3c9cf 100644
--- a/sysdeps/ieee754/float128/float128_private.h
+++ b/sysdeps/ieee754/float128/float128_private.h
@@ -154,6 +154,8 @@
#define USE_ROUNDL_BUILTIN USE_ROUNDF128_BUILTIN
#undef USE_COPYSIGNL_BUILTIN
#define USE_COPYSIGNL_BUILTIN USE_COPYSIGNF128_BUILTIN
+#undef USE_FMAL_BUILTIN
+#define USE_FMAL_BUILTIN USE_FMAF128_BUILTIN
/* IEEE function renames. */
#define __ieee754_acoshl __ieee754_acoshf128
diff --git a/sysdeps/ieee754/ldbl-128/s_fma.c b/sysdeps/ieee754/ldbl-128/s_fma.c
index 13f8ed3b87eb..0feff0a71cd1 100644
--- a/sysdeps/ieee754/ldbl-128/s_fma.c
+++ b/sysdeps/ieee754/ldbl-128/s_fma.c
@@ -21,6 +21,7 @@
#include <fenv.h>
#include <ieee754.h>
#include <libm-alias-double.h>
+#include <math-use-builtins.h>
/* This implementation relies on long double being more than twice as
precise as double and uses rounding to odd in order to avoid problems
@@ -31,6 +32,9 @@
double
__fma (double x, double y, double z)
{
+#if USE_FMA_BUILTIN
+ return __builtin_fma (x, y, z);
+#else
fenv_t env;
/* Multiplication is always exact. */
long double temp = (long double) x * (long double) y;
@@ -50,6 +54,7 @@ __fma (double x, double y, double z)
feupdateenv (&env);
/* And finally truncation with round to nearest. */
return (double) u.d;
+#endif /* ! USE_FMA_BUILTIN */
}
#ifndef __fma
libm_alias_double (__fma, fma)
diff --git a/sysdeps/ieee754/ldbl-128/s_fmal.c b/sysdeps/ieee754/ldbl-128/s_fmal.c
index 7475015bcec6..a610499e47c7 100644
--- a/sysdeps/ieee754/ldbl-128/s_fmal.c
+++ b/sysdeps/ieee754/ldbl-128/s_fmal.c
@@ -25,6 +25,7 @@
#include <math_private.h>
#include <libm-alias-ldouble.h>
#include <tininess.h>
+#include <math-use-builtins.h>
/* This implementation uses rounding to odd to avoid problems with
double rounding. See a paper by Boldo and Melquiond:
@@ -33,6 +34,9 @@
_Float128
__fmal (_Float128 x, _Float128 y, _Float128 z)
{
+#if USE_FMAL_BUILTIN
+ return __builtin_fmal (x, y, z);
+#else
union ieee854_long_double u, v, w;
int adjust = 0;
u.d = x;
@@ -296,5 +300,6 @@ __fmal (_Float128 x, _Float128 y, _Float128 z)
v.ieee.mantissa3 |= j;
return v.d * L(0x1p-228);
}
+#endif /* ! USE_FMAL_BUILTIN */
}
libm_alias_ldouble (__fma, fma)
diff --git a/sysdeps/s390/fpu/math-use-builtins.h b/sysdeps/s390/fpu/math-use-builtins.h
index eb87b6b0b16b..3a80f86b2e29 100644
--- a/sysdeps/s390/fpu/math-use-builtins.h
+++ b/sysdeps/s390/fpu/math-use-builtins.h
@@ -111,4 +111,9 @@
#define USE_SQRT_BUILTIN 0
#define USE_SQRTF_BUILTIN 0
+#define USE_FMA_BUILTIN 0
+#define USE_FMAF_BUILTIN 0
+#define USE_FMAL_BUILTIN 0
+#define USE_FMAF128_BUILTIN 0
+
#endif /* math-use-builtins.h */
--
2.20.1
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