From 8353881ede286045dc5bdc00af6407560ca5d05b Mon Sep 17 00:00:00 2001

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

Date: Wed, 11 Dec 2019 15:09:20 +0100

Subject: [PATCH 09/28] Use GCC builtins for floor functions if desired.

This patch is using the corresponding GCC builtin for floorf, floor,

floorl and floorf128 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 6c1b6a5e8cd91e0e1965509ad91e627e60eb00a3)

---

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

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

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

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

 sysdeps/ieee754/ldbl-128/s_floorl.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 64b4a4bb5b..e1c5df62e4 100644

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

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

@@ -31,4 +31,9 @@

 #define USE_RINTL_BUILTIN 0

 #define USE_RINTF128_BUILTIN 0

+#define USE_FLOOR_BUILTIN 0

+#define USE_FLOORF_BUILTIN 0

+#define USE_FLOORL_BUILTIN 0

+#define USE_FLOORF128_BUILTIN 0

+

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

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

index b551a1aafa..693938b708 100644

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

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

@@ -34,6 +34,7 @@

 #include <math_private.h>

 #include <stdint.h>

 #include <libm-alias-double.h>

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

 /*

  * floor(x)

@@ -45,6 +46,10 @@

 double

 __floor (double x)

 {

+#if USE_FLOOR_BUILTIN

+  return __builtin_floor (x);

+#else

+  /* Use generic implementation.  */

   int64_t i0;

   EXTRACT_WORDS64 (i0, x);

   int32_t j0 = ((i0 >> 52) & 0x7ff) - 0x3ff;

@@ -72,6 +77,7 @@ __floor (double x)

   else if (j0 == 0x400)

     return x + x;			/* inf or NaN */

   return x;

+#endif /* ! USE_FLOOR_BUILTIN  */

 }

 #ifndef __floor

 libm_alias_double (__floor, floor)

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

index b872aefbfd..667030ab06 100644

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

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

@@ -143,6 +143,8 @@

 #define USE_NEARBYINTL_BUILTIN USE_NEARBYINTF128_BUILTIN

 #undef USE_RINTL_BUILTIN

 #define USE_RINTL_BUILTIN USE_RINTF128_BUILTIN

+#undef USE_FLOORL_BUILTIN

+#define USE_FLOORL_BUILTIN USE_FLOORF128_BUILTIN

 /* IEEE function renames.  */

 #define __ieee754_acoshl __ieee754_acoshf128

@@ -346,6 +348,7 @@

 #define __builtin_signbitl __builtin_signbit

 #define __builtin_nearbyintl __builtin_nearbyintf128

 #define __builtin_rintl __builtin_rintf128

+#define __builtin_floorl __builtin_floorf128

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

 #define L(x) __f128 (x)

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

index 12aed343a0..6d37ab90a1 100644

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

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

@@ -23,10 +23,15 @@

 #include <math.h>

 #include <math_private.h>

 #include <libm-alias-float.h>

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

 float

 __floorf(float x)

 {

+#if USE_FLOORF_BUILTIN

+  return __builtin_floorf (x);

+#else

+  /* Use generic implementation.  */

 	int32_t i0,j0;

 	uint32_t i;

 	GET_FLOAT_WORD(i0,x);

@@ -49,6 +54,7 @@ __floorf(float x)

 	}

 	SET_FLOAT_WORD(x,i0);

 	return x;

+#endif /* ! USE_FLOORF_BUILTIN  */

 }

 #ifndef __floorf

 libm_alias_float (__floor, floor)

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

index f9c5e014f9..6143fe6ec5 100644

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

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

@@ -27,9 +27,14 @@ static char rcsid[] = "$NetBSD: $";

 #include <math.h>

 #include <math_private.h>

 #include <libm-alias-ldouble.h>

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

 _Float128 __floorl(_Float128 x)

 {

+#if USE_FLOORL_BUILTIN

+  return __builtin_floorl (x);

+#else

+  /* Use generic implementation.  */

 	int64_t i0,i1,j0;

 	uint64_t i,j;

 	GET_LDOUBLE_WORDS64(i0,i1,x);

@@ -64,5 +69,6 @@ _Float128 __floorl(_Float128 x)

 	}

 	SET_LDOUBLE_WORDS64(x,i0,i1);

 	return x;

+#endif /* ! USE_FLOORL_BUILTIN  */

 }

 libm_alias_ldouble (__floor, floor)

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

index 8b702a6a90..c213c16c6f 100644

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

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

@@ -34,12 +34,18 @@

 # define USE_RINTF_BUILTIN 1

 # define USE_RINTL_BUILTIN 1

+# define USE_FLOOR_BUILTIN 1

+# define USE_FLOORF_BUILTIN 1

+# define USE_FLOORL_BUILTIN 1

+

 # if __GNUC_PREREQ (8, 0)

 #  define USE_NEARBYINTF128_BUILTIN 1

 #  define USE_RINTF128_BUILTIN 1

+#  define USE_FLOORF128_BUILTIN 1

 # else

 #  define USE_NEARBYINTF128_BUILTIN 0

 #  define USE_RINTF128_BUILTIN 0

+#  define USE_FLOORF128_BUILTIN 0

 # endif

 #else

@@ -55,6 +61,11 @@

 # define USE_RINTL_BUILTIN 0

 # define USE_RINTF128_BUILTIN 0

+# define USE_FLOOR_BUILTIN 0

+# define USE_FLOORF_BUILTIN 0

+# define USE_FLOORL_BUILTIN 0

+# define USE_FLOORF128_BUILTIN 0

+

 #endif /* ! HAVE_S390_MIN_Z196_ZARCH_ASM_SUPPORT  */

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

-- 

2.18.2