From abc72a0694c1c3d08354170da343eead8d9afcc1 Mon Sep 17 00:00:00 2001

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

Date: Wed, 11 Dec 2019 15:09:22 +0100

Subject: [PATCH 11/28] Use GCC builtins for trunc functions if desired.

This patch is using the corresponding GCC builtin for truncf, trunc,

truncl and truncf128 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 1ac9c1cf87216bf9f8ac4f7c9754d025d9f2c4ae)

---

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

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

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

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

 sysdeps/ieee754/ldbl-128/s_truncl.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 076ec661b0..ab379f45ba 100644

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

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

@@ -41,4 +41,9 @@

 #define USE_CEILL_BUILTIN 0

 #define USE_CEILF128_BUILTIN 0

+#define USE_TRUNC_BUILTIN 0

+#define USE_TRUNCF_BUILTIN 0

+#define USE_TRUNCL_BUILTIN 0

+#define USE_TRUNCF128_BUILTIN 0

+

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

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

index 38bb33d337..708169c727 100644

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

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

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

 #include <math_private.h>

 #include <libm-alias-double.h>

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

 double

 __trunc (double x)

 {

+#if USE_TRUNC_BUILTIN

+  return __builtin_trunc (x);

+#else

+  /* Use generic implementation.  */

   int64_t i0, j0;

   int64_t sx;

@@ -48,6 +53,7 @@ __trunc (double x)

     }

   return x;

+#endif /* ! USE_TRUNC_BUILTIN  */

 }

 #ifndef __trunc

 libm_alias_double (__trunc, trunc)

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

index 19352ca26c..e248600ec2 100644

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

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

@@ -147,6 +147,8 @@

 #define USE_FLOORL_BUILTIN USE_FLOORF128_BUILTIN

 #undef USE_CEILL_BUILTIN

 #define USE_CEILL_BUILTIN USE_CEILF128_BUILTIN

+#undef USE_TRUNCL_BUILTIN

+#define USE_TRUNCL_BUILTIN USE_TRUNCF128_BUILTIN

 /* IEEE function renames.  */

 #define __ieee754_acoshl __ieee754_acoshf128

@@ -352,6 +354,7 @@

 #define __builtin_rintl __builtin_rintf128

 #define __builtin_floorl __builtin_floorf128

 #define __builtin_ceill __builtin_ceilf128

+#define __builtin_truncl __builtin_truncf128

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

 #define L(x) __f128 (x)

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

index 2e1464aeac..71491e5175 100644

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

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

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

 #include <math_private.h>

 #include <libm-alias-float.h>

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

 float

 __truncf (float x)

 {

+#if USE_TRUNCF_BUILTIN

+  return __builtin_truncf (x);

+#else

+  /* Use generic implementation.  */

   int32_t i0, j0;

   int sx;

@@ -48,6 +53,7 @@ __truncf (float x)

     }

   return x;

+#endif /* ! USE_TRUNCF_BUILTIN  */

 }

 #ifndef __truncf

 libm_alias_float (__trunc, trunc)

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

index f858ede3d2..aa49daaf85 100644

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

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

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

 #include <math_private.h>

 #include <libm-alias-ldouble.h>

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

 _Float128

 __truncl (_Float128 x)

 {

+#if USE_TRUNCL_BUILTIN

+  return __builtin_truncl (x);

+#else

+  /* Use generic implementation.  */

   int32_t j0;

   uint64_t i0, i1, sx;

@@ -53,5 +58,6 @@ __truncl (_Float128 x)

     }

   return x;

+#endif /* ! USE_TRUNCL_BUILTIN  */

 }

 libm_alias_ldouble (__trunc, trunc)

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

index 5435cbb65f..a39715c612 100644

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

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

@@ -42,16 +42,22 @@

 # define USE_CEILF_BUILTIN 1

 # define USE_CEILL_BUILTIN 1

+# define USE_TRUNC_BUILTIN 1

+# define USE_TRUNCF_BUILTIN 1

+# define USE_TRUNCL_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

 # 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

 # endif

 #else

@@ -77,6 +83,11 @@

 # define USE_CEILL_BUILTIN 0

 # define USE_CEILF128_BUILTIN 0

+# define USE_TRUNC_BUILTIN 0

+# define USE_TRUNCF_BUILTIN 0

+# define USE_TRUNCL_BUILTIN 0

+# define USE_TRUNCF128_BUILTIN 0

+

 #endif /* ! HAVE_S390_MIN_Z196_ZARCH_ASM_SUPPORT  */

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

-- 

2.18.2