Use GCC builtins for roundeven functions if desired.

This patch is using the corresponding GCC builtin for roundevenf,
roundeven and roundevenl if the USE_FUNCTION_BUILTIN macros are defined
to one in math-use-builtins.h.

These builtin functions is supported since GCC 10.

The code of the generic implementation is not changed.

Signed-off-by: Shen-Ta Hsieh <ibmibmibm.tw@gmail.com>
Reviewed-by: H.J. Lu <hjl.tools@gmail.com>
This commit is contained in:
Shen-Ta Hsieh 2021-05-24 09:43:12 +08:00 committed by H.J. Lu
parent 1683249d17
commit eb9066203f
6 changed files with 22 additions and 0 deletions

View file

@ -0,0 +1,4 @@
#define USE_ROUNDEVEN_BUILTIN 0
#define USE_ROUNDEVENF_BUILTIN 0
#define USE_ROUNDEVENL_BUILTIN 0
#define USE_ROUNDEVENF128_BUILTIN 0

View file

@ -30,6 +30,7 @@
#include <math-use-builtins-ceil.h>
#include <math-use-builtins-trunc.h>
#include <math-use-builtins-round.h>
#include <math-use-builtins-roundeven.h>
#include <math-use-builtins-copysign.h>
#include <math-use-builtins-sqrt.h>
#include <math-use-builtins-fma.h>

View file

@ -21,6 +21,7 @@
#include <math_private.h>
#include <libm-alias-double.h>
#include <stdint.h>
#include <math-use-builtins.h>
#define BIAS 0x3ff
#define MANT_DIG 53
@ -29,6 +30,9 @@
double
__roundeven (double x)
{
#if USE_ROUNDEVEN_BUILTIN
return __builtin_roundeven (x);
#else
uint64_t ix, ux;
EXTRACT_WORDS64 (ix, x);
ux = ix & 0x7fffffffffffffffULL;
@ -66,6 +70,7 @@ __roundeven (double x)
ix &= 0x8000000000000000ULL;
INSERT_WORDS64 (x, ix);
return x;
#endif /* ! USE_ROUNDEVEN_BUILTIN */
}
#ifndef __roundeven
libm_alias_double (__roundeven, roundeven)

View file

@ -152,6 +152,8 @@
#define USE_TRUNCL_BUILTIN USE_TRUNCF128_BUILTIN
#undef USE_ROUNDL_BUILTIN
#define USE_ROUNDL_BUILTIN USE_ROUNDF128_BUILTIN
#undef USE_ROUNDEVENL_BUILTIN
#define USE_ROUNDEVENL_BUILTIN USE_ROUNDEVENF128_BUILTIN
#undef USE_COPYSIGNL_BUILTIN
#define USE_COPYSIGNL_BUILTIN USE_COPYSIGNF128_BUILTIN
#undef USE_FMAL_BUILTIN

View file

@ -21,6 +21,7 @@
#include <math.h>
#include <math_private.h>
#include <libm-alias-float.h>
#include <math-use-builtins.h>
#include <stdint.h>
#define BIAS 0x7f
@ -30,6 +31,9 @@
float
__roundevenf (float x)
{
#if USE_ROUNDEVENF_BUILTIN
return __builtin_roundevenf (x);
#else
uint32_t ix, ux;
GET_FLOAT_WORD (ix, x);
ux = ix & 0x7fffffff;
@ -67,6 +71,7 @@ __roundevenf (float x)
ix &= 0x80000000;
SET_FLOAT_WORD (x, ix);
return x;
#endif /* ! USE_ROUNDEVENF_BUILTIN */
}
#ifndef __roundevenf
libm_alias_float (__roundeven, roundeven)

View file

@ -21,6 +21,7 @@
#include <math.h>
#include <math_private.h>
#include <libm-alias-ldouble.h>
#include <math-use-builtins.h>
#include <stdint.h>
#define BIAS 0x3fff
@ -30,6 +31,9 @@
_Float128
__roundevenl (_Float128 x)
{
#if USE_ROUNDEVENL_BUILTIN
return __builtin_roundevenl (x);
#else
uint64_t hx, lx, uhx;
GET_LDOUBLE_WORDS64 (hx, lx, x);
uhx = hx & 0x7fffffffffffffffULL;
@ -101,5 +105,6 @@ __roundevenl (_Float128 x)
}
SET_LDOUBLE_WORDS64 (x, hx, lx);
return x;
#endif /* ! USE_ROUNDEVENL_BUILTIN */
}
libm_alias_ldouble (__roundeven, roundeven)