From f49dd4cc4e295803e517190d1798bd84561d56f4 Mon Sep 17 00:00:00 2001

From: Stefan Liebler <stli@linux.ibm.com>

Date: Wed, 11 Dec 2019 15:09:24 +0100

Subject: [PATCH 12/28] Use GCC builtins for round functions if desired.

This patch is using the corresponding GCC builtin for roundf, round,

roundl and roundf128 if the USE_FUNCTION_BUILTIN macros are defined to one

in math-use-builtins.h.

This is the case for s390 if build with at least --march=z196 --mzarch.

Otherwise the generic implementation is used.  The code of the generic

implementation is not changed.

Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>

(cherry picked from commit f82996f8159981619ac7ed8a4c1838c2ad72ab61)

---

 sysdeps/generic/math-use-builtins.h         |  5 +++++

 sysdeps/ieee754/dbl-64/s_round.c            |  6 ++++++

 sysdeps/ieee754/float128/float128_private.h |  3 +++

 sysdeps/ieee754/flt-32/s_roundf.c           |  6 ++++++

 sysdeps/ieee754/ldbl-128/s_roundl.c         |  6 ++++++

 sysdeps/s390/fpu/math-use-builtins.h        | 11 +++++++++++

 6 files changed, 37 insertions(+)

diff --git a/sysdeps/generic/math-use-builtins.h b/sysdeps/generic/math-use-builtins.h

index ab379f45ba..34ca438a8c 100644

--- a/sysdeps/generic/math-use-builtins.h

+++ b/sysdeps/generic/math-use-builtins.h

@@ -46,4 +46,9 @@

 #define USE_TRUNCL_BUILTIN 0

 #define USE_TRUNCF128_BUILTIN 0

+#define USE_ROUND_BUILTIN 0

+#define USE_ROUNDF_BUILTIN 0

+#define USE_ROUNDL_BUILTIN 0

+#define USE_ROUNDF128_BUILTIN 0

+

 #endif /* math-use-builtins.h */

diff --git a/sysdeps/ieee754/dbl-64/s_round.c b/sysdeps/ieee754/dbl-64/s_round.c

index bf9922edca..1f8482adf8 100644

--- a/sysdeps/ieee754/dbl-64/s_round.c

+++ b/sysdeps/ieee754/dbl-64/s_round.c

@@ -22,11 +22,16 @@

 #include <math_private.h>

 #include <libm-alias-double.h>

 #include <stdint.h>

+#include <math-use-builtins.h>

 double

 __round (double x)

 {

+#if USE_ROUND_BUILTIN

+  return __builtin_round (x);

+#else

+  /* Use generic implementation.  */

   int64_t i0, j0;

   EXTRACT_WORDS64 (i0, x);

@@ -61,5 +66,6 @@ __round (double x)

   INSERT_WORDS64 (x, i0);

   return x;

+#endif /* ! USE_ROUND_BUILTIN  */

 }

 libm_alias_double (__round, round)

diff --git a/sysdeps/ieee754/float128/float128_private.h b/sysdeps/ieee754/float128/float128_private.h

index e248600ec2..3297a71e44 100644

--- a/sysdeps/ieee754/float128/float128_private.h

+++ b/sysdeps/ieee754/float128/float128_private.h

@@ -149,6 +149,8 @@

 #define USE_CEILL_BUILTIN USE_CEILF128_BUILTIN

 #undef USE_TRUNCL_BUILTIN

 #define USE_TRUNCL_BUILTIN USE_TRUNCF128_BUILTIN

+#undef USE_ROUNDL_BUILTIN

+#define USE_ROUNDL_BUILTIN USE_ROUNDF128_BUILTIN

 /* IEEE function renames.  */

 #define __ieee754_acoshl __ieee754_acoshf128

@@ -355,6 +357,7 @@

 #define __builtin_floorl __builtin_floorf128

 #define __builtin_ceill __builtin_ceilf128

 #define __builtin_truncl __builtin_truncf128

+#define __builtin_roundl __builtin_roundf128

 /* Get the constant suffix from bits/floatn-compat.h.  */

 #define L(x) __f128 (x)

diff --git a/sysdeps/ieee754/flt-32/s_roundf.c b/sysdeps/ieee754/flt-32/s_roundf.c

index 7c95125d9c..6fdfbbbade 100644

--- a/sysdeps/ieee754/flt-32/s_roundf.c

+++ b/sysdeps/ieee754/flt-32/s_roundf.c

@@ -21,11 +21,16 @@

 #include <math_private.h>

 #include <libm-alias-float.h>

+#include <math-use-builtins.h>

 float

 __roundf (float x)

 {

+#if USE_ROUNDF_BUILTIN

+  return __builtin_roundf (x);

+#else

+  /* Use generic implementation.  */

   int32_t i0, j0;

   GET_FLOAT_WORD (i0, x);

@@ -60,5 +65,6 @@ __roundf (float x)

   SET_FLOAT_WORD (x, i0);

   return x;

+#endif /* ! USE_ROUNDF_BUILTIN  */

 }

 libm_alias_float (__round, round)

diff --git a/sysdeps/ieee754/ldbl-128/s_roundl.c b/sysdeps/ieee754/ldbl-128/s_roundl.c

index 22789cedf3..564f8ac1b8 100644

--- a/sysdeps/ieee754/ldbl-128/s_roundl.c

+++ b/sysdeps/ieee754/ldbl-128/s_roundl.c

@@ -22,11 +22,16 @@

 #include <math_private.h>

 #include <libm-alias-ldouble.h>

+#include <math-use-builtins.h>

 _Float128

 __roundl (_Float128 x)

 {

+#if USE_ROUNDL_BUILTIN

+  return __builtin_roundl (x);

+#else

+  /* Use generic implementation.  */

   int32_t j0;

   uint64_t i1, i0;

@@ -77,5 +82,6 @@ __roundl (_Float128 x)

   SET_LDOUBLE_WORDS64 (x, i0, i1);

   return x;

+#endif /* ! USE_ROUNDL_BUILTIN  */

 }

 libm_alias_ldouble (__round, round)

diff --git a/sysdeps/s390/fpu/math-use-builtins.h b/sysdeps/s390/fpu/math-use-builtins.h

index a39715c612..51cb9f91ab 100644

--- a/sysdeps/s390/fpu/math-use-builtins.h

+++ b/sysdeps/s390/fpu/math-use-builtins.h

@@ -46,18 +46,24 @@

 # define USE_TRUNCF_BUILTIN 1

 # define USE_TRUNCL_BUILTIN 1

+# define USE_ROUND_BUILTIN 1

+# define USE_ROUNDF_BUILTIN 1

+# define USE_ROUNDL_BUILTIN 1

+

 # if __GNUC_PREREQ (8, 0)

 #  define USE_NEARBYINTF128_BUILTIN 1

 #  define USE_RINTF128_BUILTIN 1

 #  define USE_FLOORF128_BUILTIN 1

 #  define USE_CEILF128_BUILTIN 1

 #  define USE_TRUNCF128_BUILTIN 1

+#  define USE_ROUNDF128_BUILTIN 1

 # else

 #  define USE_NEARBYINTF128_BUILTIN 0

 #  define USE_RINTF128_BUILTIN 0

 #  define USE_FLOORF128_BUILTIN 0

 #  define USE_CEILF128_BUILTIN 0

 #  define USE_TRUNCF128_BUILTIN 0

+#  define USE_ROUNDF128_BUILTIN 0

 # endif

 #else

@@ -88,6 +94,11 @@

 # define USE_TRUNCL_BUILTIN 0

 # define USE_TRUNCF128_BUILTIN 0

+# define USE_ROUND_BUILTIN 0

+# define USE_ROUNDF_BUILTIN 0

+# define USE_ROUNDL_BUILTIN 0

+# define USE_ROUNDF128_BUILTIN 0

+

 #endif /* ! HAVE_S390_MIN_Z196_ZARCH_ASM_SUPPORT  */

 #endif /* math-use-builtins.h */

-- 

2.18.2