From f8e8b8ed9f266097b42a77359445372d82365916 Mon Sep 17 00:00:00 2001 From: Joseph Myers Date: Wed, 19 Oct 2016 01:49:09 +0000 Subject: Add getpayload, getpayloadf, getpayloadl. TS 18661-1 defines functions for manipulating the payloads of NaNs. This patch implements the getpayload functions for glibc; these extract the NaN payload (from an argument passed as a pointer, for which corresponding libm-test support is added) and return it in the same floating-point type. The return value of these functions is unspecified for non-NaN arguments; the patch does the simplest thing to implement, which is that the functions do not check whether the argument is a NaN and just treat the relevant bits of the representation as a payload regardless. A conversion from integer to floating-point is used to produce the required return value, except in the ldbl-128 case; as 128-bit integers are not supported for all configurations using ldbl-128, the code constructs the required floating-point representation of the return value directly instead. Tested for x86_64, x86, mips64 and powerpc. * math/bits/mathcalls.h [__GLIBC_USE (IEC_60559_BFP_EXT)] (getpayload): New declaration. * math/Versions (getpayload): New libm symbol at version GLIBC_2.25. (getpayloadf): Likewise. (getpayloadl): Likewise. * math/Makefile (libm-calls): Add s_getpayloadF. * math/libm-test.inc: Include . (struct test_f_f_data): Add comment. (RUN_TEST_fp_f): New macro. (RUN_TEST_LOOP_fp_f): Likewise. (getpayload_test_data): New array. (getpayload_test): New function. (main): Call getpayload_test. * math/gen-libm-test.pl (parse_args): Handle 'p' in argument descriptor. * manual/arith.texi (FP Bit Twiddling): Document getpayload, getpayloadf and getpayloadl. * manual/libm-err-tab.pl: Update comment on interfaces without ulps tabulated. * sysdeps/ieee754/dbl-64/s_getpayload.c: New file. * sysdeps/ieee754/dbl-64/wordsize-64/s_getpayload.c: Likewise. * sysdeps/ieee754/flt-32/s_getpayloadf.c: Likewise. * sysdeps/ieee754/ldbl-128/s_getpayloadl.c: Likewise. * sysdeps/ieee754/ldbl-128ibm/s_getpayloadl.c: Likewise. * sysdeps/ieee754/ldbl-96/s_getpayloadl.c: 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. --- manual/arith.texi | 20 ++++++++++++++++++++ 1 file changed, 20 insertions(+) (limited to 'manual/arith.texi') diff --git a/manual/arith.texi b/manual/arith.texi index 282ca45e08..e53988a083 100644 --- a/manual/arith.texi +++ b/manual/arith.texi @@ -1854,6 +1854,26 @@ The argument @var{tagp} is used in an unspecified manner. On @w{IEEE selects one. On other systems it may do nothing. @end deftypefun +@comment math.h +@comment ISO +@deftypefun double getpayload (const double *@var{x}) +@comment math.h +@comment ISO +@deftypefunx float getpayloadf (const float *@var{x}) +@comment math.h +@comment ISO +@deftypefunx {long double} getpayloadl (const long double *@var{x}) +@safety{@prelim{}@mtsafe{}@assafe{}@acsafe{}} +IEEE 754 defines the @dfn{payload} of a NaN to be an integer value +encoded in the representation of the NaN. Payloads are typically +propagated from NaN inputs to the result of a floating-point +operation. These functions, defined by TS 18661-1:2014, return the +payload of the NaN pointed to by @var{x} (returned as a positive +integer, or positive zero, represented as a floating-point number); if +@var{x} is not a NaN, they return an unspecified value. They raise no +floating-point exceptions even for signaling NaNs. +@end deftypefun + @node FP Comparison Functions @subsection Floating-Point Comparison Functions @cindex unordered comparison -- cgit v1.2.3