glibc/sysdeps/ieee754/ldbl-128ibm/s_roundl.c
Joseph Myers 9755bc4686 Use round functions not __round functions in glibc libm.
Continuing the move to use, within libm, public names for libm
functions that can be inlined as built-in functions on many
architectures, this patch moves calls to __round functions to call the
corresponding round names instead, with asm redirection to __round
when the calls are not inlined.

An additional complication arises in
sysdeps/ieee754/ldbl-128ibm/e_expl.c, where a call to roundl, with the
result converted to int, gets converted by the compiler to call
lroundl in the case of 32-bit long, so resulting in localplt test
failures.  It's logically correct to let the compiler make such an
optimization; an appropriate asm redirection of lroundl to __lroundl
is thus added to that file (it's not needed anywhere else).

Tested for x86_64, and with build-many-glibcs.py.

	* include/math.h [!_ISOMAC && !(__FINITE_MATH_ONLY__ &&
	__FINITE_MATH_ONLY__ > 0) && !NO_MATH_REDIRECT] (round): Redirect
	using MATH_REDIRECT.
	* sysdeps/aarch64/fpu/s_round.c: Define NO_MATH_REDIRECT before
	header inclusion.
	* sysdeps/aarch64/fpu/s_roundf.c: Likewise.
	* sysdeps/ieee754/dbl-64/s_round.c: Likewise.
	* sysdeps/ieee754/dbl-64/wordsize-64/s_round.c: Likewise.
	* sysdeps/ieee754/float128/s_roundf128.c: Likewise.
	* sysdeps/ieee754/flt-32/s_roundf.c: Likewise.
	* sysdeps/ieee754/ldbl-128/s_roundl.c: Likewise.
	* sysdeps/ieee754/ldbl-96/s_roundl.c: Likewise.
	* sysdeps/powerpc/powerpc32/power4/fpu/multiarch/s_round.c: Likewise.
	* sysdeps/powerpc/powerpc32/power4/fpu/multiarch/s_roundf.c: Likewise.
	* sysdeps/powerpc/powerpc64/fpu/multiarch/s_round.c: Likewise.
	* sysdeps/powerpc/powerpc64/fpu/multiarch/s_roundf.c: Likewise.
	* sysdeps/riscv/rv64/rvd/s_round.c: Likewise.
	* sysdeps/riscv/rvf/s_roundf.c: Likewise.
	* sysdeps/ieee754/ldbl-128ibm/s_roundl.c: Likewise.
	(round): Redirect to __round.
	(__roundl): Call round instead of __round.
	* sysdeps/powerpc/fpu/math_private.h [_ARCH_PWR5X] (__round):
	Remove macro.
	[_ARCH_PWR5X] (__roundf): Likewise.
	* sysdeps/ieee754/dbl-64/e_gamma_r.c (gamma_positive): Use round
	functions instead of __round variants.
	* sysdeps/ieee754/flt-32/e_gammaf_r.c (gammaf_positive): Likewise.
	* sysdeps/ieee754/ldbl-128/e_gammal_r.c (gammal_positive):
	Likewise.
	* sysdeps/ieee754/ldbl-128ibm/e_gammal_r.c (gammal_positive):
	Likewise.
	* sysdeps/ieee754/ldbl-96/e_gammal_r.c (gammal_positive):
	Likewise.
	* sysdeps/x86/fpu/powl_helper.c (__powl_helper): Likewise.
	* sysdeps/ieee754/ldbl-128ibm/e_expl.c (lroundl): Redirect to
	__lroundl.
	(__ieee754_expl): Call roundl instead of __roundl.
2018-09-27 12:35:23 +00:00

92 lines
2.3 KiB
C

/* Round to int long double floating-point values.
IBM extended format long double version.
Copyright (C) 2006-2018 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, see
<http://www.gnu.org/licenses/>. */
/* This has been coded in assembler because GCC makes such a mess of it
when it's coded in C. */
#define NO_MATH_REDIRECT
#include <math.h>
#include <math_private.h>
#include <math_ldbl_opt.h>
#include <float.h>
#include <ieee754.h>
double round (double) asm ("__round");
long double
__roundl (long double x)
{
double xh, xl, hi, lo;
ldbl_unpack (x, &xh, &xl);
/* Return Inf, Nan, +/-0 unchanged. */
if (__builtin_expect (xh != 0.0
&& __builtin_isless (__builtin_fabs (xh),
__builtin_inf ()), 1))
{
hi = round (xh);
if (hi != xh)
{
/* The high part is not an integer; the low part only
affects the result if the high part is exactly half way
between two integers and the low part is nonzero with the
opposite sign. */
if (fabs (hi - xh) == 0.5)
{
if (xh > 0 && xl < 0)
xh = hi - 1;
else if (xh < 0 && xl > 0)
xh = hi + 1;
else
xh = hi;
}
else
xh = hi;
xl = 0;
}
else
{
/* The high part is a nonzero integer. */
lo = round (xl);
if (fabs (lo - xl) == 0.5)
{
if (xh > 0 && xl < 0)
xl = lo + 1;
else if (xh < 0 && lo > 0)
xl = lo - 1;
else
xl = lo;
}
else
xl = lo;
xh = hi;
ldbl_canonicalize_int (&xh, &xl);
}
}
else
/* Quiet signaling NaN arguments. */
xh += xh;
return ldbl_pack (xh, xl);
}
long_double_symbol (libm, __roundl, roundl);