mirror of
https://sourceware.org/git/glibc.git
synced 2024-11-25 06:20:06 +00:00
eaf5ad0bc4
TS 18661-1 defines canonicalize functions to produce a canonical version of a floating-point representation. This patch implements these functions for glibc. As with the iscanonical macro, these functions are oriented to the decimal floating-point case, where some values have both canonical and noncanonical representations. However, the functions have a return value that says whether they succeeded in storing a canonical result; thus, they can fail for the case of an invalid representation (while still not making any particular choice from among multiple equally canonical valid representations of the same value). Since no floating-point formats in glibc actually have noncanonical valid representations, a type-generic implementation of these functions can be used that expects iscanonical to return 0 only for invalid representations. Now that iscanonical is used within libm.so, libm_hidden_proto / libm_hidden_def are added for __iscanonicall. The definition of these functions is intended to correspond to a convertFormat operation to the same floating-point format. Thus, they convert signaling NaNs to quiet NaNs, raising the "invalid" exception. Such a conversion "should" produce "the canonical version of that signaling NaN made quiet". libm-test.inc is made to check NaN payloads for the output of these functions, a new feature (at some point manipulation functions such as fabs and copysign should have tests added that verify payload preservation for them). As however some architectures may not follow the recommended practice of preserving NaN payloads when converting a signaling NaN to quiet, a new math-tests.h macro SNAN_TESTS_PRESERVE_PAYLOAD is added, and defined to 0 for non-NAN2008 MIPS; any other architectures seeing test failures for lack of payload preservation in this case should also define this macro to 0. (If any cases arise where the sign isn't preserved either, those should have a similar macro added.) The ldbl-96 and ldbl-128ibm tests of iscanonical are renamed and adapted to test canonicalizel as well on the same representations. Tested for x86_64, x86, mips64 and powerpc. * math/bits/mathcalls.h [__GLIBC_USE (IEC_60559_BFP_EXT)] (canonicalize): New declaration. * math/Versions (canonicalize): New libm symbol at version GLIBC_2.25. (canonicalizef): Likewise. (canonicalizel): Likewise. * math/Makefile (gen-libm-calls): Add s_canonicalizeF. * math/s_canonicalize_template.c: New file. * math/libm-test.inc: Update comment on functions tested and testing of NaN payloads. (TEST_NAN_PAYLOAD): New macro. (NO_TEST_INLINE): Update value. (XFAIL_TEST): Likewise. (ERRNO_UNCHANGED): Likewise. (ERRNO_EDOM): Likewise. (ERRNO_ERANGE): Likewise. (IGNORE_RESULT): Likewise. (NON_FINITE): Likewise. (TEST_SNAN): Likewise. (NO_TEST_MATHVEC): Likewise. (TEST_NAN_PAYLOAD_CANONICALIZE): New macro. (check_float_internal): Check NaN payloads if TEST_NAN_PAYLOAD. (struct test_Ffp_b1_data): New type. (RUN_TEST_Ffp_b1): New macro. (RUN_TEST_LOOP_Ffp_b1): Likewise. (canonicalize_test_data): New array. (canonicalize_test): New function. (main): Call canonicalize_test. * manual/arith.texi (FP Bit Twiddling): Document canonicalize, canonicalizef and canonicalizel. * manual/libm-err-tab.pl: Update comment on interfaces without ulps tabulated. * sysdeps/ieee754/ldbl-opt/nldbl-canonicalize.c: New file. * sysdeps/ieee754/ldbl-opt/s_canonicalizel.c: Likewise. * sysdeps/ieee754/ldbl-opt/Makefile (libnldbl-calls): Add canonicalize. (CFLAGS-nldbl-canonicalize.c): New variable. * sysdeps/ieee754/ldbl-128ibm/test-iscanonical-ldbl-128ibm.c: Move to ... * sysdeps/ieee754/ldbl-128ibm/test-canonical-ldbl-128ibm.c: ... here. (do_test): Also test canonicalizel. * sysdeps/ieee754/ldbl-128ibm/Makefile (tests): Change test-iscanonical-ldbl-128ibm to test-canonical-ldbl-128ibm. * sysdeps/ieee754/ldbl-128ibm/include/bits/iscanonical.h: New file. * sysdeps/ieee754/ldbl-128ibm/s_iscanonicall.c (__iscanonicall): Use libm_hidden_def. * sysdeps/ieee754/ldbl-96/test-iscanonical-ldbl-96.c: Move to ... * sysdeps/ieee754/ldbl-96/test-canonical-ldbl-96.c: ... here. (do_test): Also test canonicalizel. * sysdeps/ieee754/ldbl-96/Makefile (tests): Change test-iscanonical-ldbl-96 to test-canonical-ldbl-96. * sysdeps/ieee754/ldbl-96/include/bits/iscanonical.h: New file. * sysdeps/ieee754/ldbl-96/s_iscanonicall.c (__iscanonicall): Use libm_hidden_def. * sysdeps/generic/math-tests.h (SNAN_TESTS_PRESERVE_PAYLOAD): New macro. * sysdeps/mips/math-tests.h [__mips_hard_float && !__mips_nan2008] (SNAN_TESTS_PRESERVE_PAYLOAD): Likewise. * sysdeps/nacl/libm.abilist: Update. * sysdeps/unix/sysv/linux/aarch64/libm.abilist: Likewise. * sysdeps/unix/sysv/linux/alpha/libm.abilist: Likewise. * sysdeps/unix/sysv/linux/arm/libm.abilist: Likewise. * sysdeps/unix/sysv/linux/hppa/libm.abilist: Likewise. * sysdeps/unix/sysv/linux/i386/libm.abilist: Likewise. * sysdeps/unix/sysv/linux/ia64/libm.abilist: Likewise. * sysdeps/unix/sysv/linux/m68k/coldfire/libm.abilist: Likewise. * sysdeps/unix/sysv/linux/m68k/m680x0/libm.abilist: Likewise. * sysdeps/unix/sysv/linux/microblaze/libm.abilist: Likewise. * sysdeps/unix/sysv/linux/mips/mips32/libm.abilist: Likewise. * sysdeps/unix/sysv/linux/mips/mips64/libm.abilist: Likewise. * sysdeps/unix/sysv/linux/nios2/libm.abilist: Likewise. * sysdeps/unix/sysv/linux/powerpc/powerpc32/fpu/libm.abilist: Likewise. * sysdeps/unix/sysv/linux/powerpc/powerpc32/nofpu/libm.abilist: Likewise. * sysdeps/unix/sysv/linux/powerpc/powerpc64/libm-le.abilist: Likewise. * sysdeps/unix/sysv/linux/powerpc/powerpc64/libm.abilist: Likewise. * sysdeps/unix/sysv/linux/s390/s390-32/libm.abilist: Likewise. * sysdeps/unix/sysv/linux/s390/s390-64/libm.abilist: Likewise. * sysdeps/unix/sysv/linux/sh/libm.abilist: Likewise. * sysdeps/unix/sysv/linux/sparc/sparc32/libm.abilist: Likewise. * sysdeps/unix/sysv/linux/sparc/sparc64/libm.abilist: Likewise. * sysdeps/unix/sysv/linux/tile/tilegx/tilegx32/libm.abilist: Likewise. * sysdeps/unix/sysv/linux/tile/tilegx/tilegx64/libm.abilist: Likewise. * sysdeps/unix/sysv/linux/tile/tilepro/libm.abilist: Likewise. * sysdeps/unix/sysv/linux/x86_64/64/libm.abilist: Likewise. * sysdeps/unix/sysv/linux/x86_64/x32/libm.abilist: Likewise.
38 lines
1.3 KiB
C
38 lines
1.3 KiB
C
/* Canonicalize floating-point representation.
|
|
Copyright (C) 2016 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/>. */
|
|
|
|
#include <math.h>
|
|
|
|
int
|
|
M_DECL_FUNC (__canonicalize) (FLOAT *cx, const FLOAT *x)
|
|
{
|
|
FLOAT val = *x;
|
|
/* For all binary formats supported by glibc, iscanonical only fails
|
|
if the representation is not a valid representation of the type,
|
|
so the only work to do is for signaling NaNs. */
|
|
if (!iscanonical (val))
|
|
return 1;
|
|
if (issignaling (val))
|
|
*cx = val + val;
|
|
else
|
|
*cx = val;
|
|
return 0;
|
|
}
|
|
|
|
declare_mgen_alias (__canonicalize, canonicalize)
|