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2016-12-21Add roundeven, roundevenf, roundevenl.Joseph Myers6-3/+624
TS 18661-1 defines roundeven functions that round a floating-point number to the nearest integer, in that floating-point type, with ties rounding to even (whereas the round functions round ties away from zero). As with other such functions, they raise no exceptions apart from "invalid" for signaling NaNs. There was a previous user request for this functionality in glibc in <https://sourceware.org/ml/libc-help/2015-02/msg00005.html>. This patch implements these functions for glibc. The implementations use integer bit-manipulation (or roundeven on the high and low parts, in the IBM long double case). It's possible that there may be faster approaches on some architectures (in particular, on AArch64 the frintn instruction should do exactly what's required); I'll leave it to architecture maintainers or others interested to implement such architecture-specific versions if desired. (Where architectures have instructions to round to nearest integer in the current rounding mode, implementations saving and restoring the rounding mode - and dealing with exceptions if those instructions generate "inexact" - are also possible, though their performance depends on the cost of manipulating exceptions / rounding mode state.) Tested for x86_64, x86, mips64 and powerpc. * math/bits/mathcalls.h [__GLIBC_USE (IEC_60559_BFP_EXT)] (roundeven): New declaration. * math/tgmath.h [__GLIBC_USE (IEC_60559_BFP_EXT)] (roundeven): New macro. * math/Versions (roundeven): New libm symbol at version GLIBC_2.25. (roundevenf): Likewise. (roundevenl): Likewise. * math/Makefile (libm-calls): Add s_roundevenF. * math/libm-test.inc (roundeven_test_data): New array. (roundeven_test): New function. (main): Call roundeven_test. * math/test-tgmath.c (NCALLS): Increase to 134. (F(compile_test)): Call roundeven. (F(roundeven)): New function. * manual/arith.texi (Rounding Functions): Document roundeven, roundevenf and roundevenl. * manual/libm-err-tab.pl (@all_functions): Add roundeven. * include/math.h (roundeven): Use libm_hidden_proto. * sysdeps/ieee754/dbl-64/s_roundeven.c: New file. * sysdeps/ieee754/dbl-64/wordsize-64/s_roundeven.c: Likewise. * sysdeps/ieee754/flt-32/s_roundevenf.c: Likewise. * sysdeps/ieee754/ldbl-128/s_roundevenl.c: Likewise. * sysdeps/ieee754/ldbl-128ibm/s_roundevenl.c: Likewise. * sysdeps/ieee754/ldbl-96/s_roundevenl.c: Likewise. * sysdeps/ieee754/ldbl-opt/Makefile (libnldbl-calls): Add roundeven. (CFLAGS-nldbl-roundeven.c): New variable. * sysdeps/ieee754/ldbl-opt/nldbl-roundeven.c: New file. * 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.
2016-12-20Add preprocessor indentation for llogb macro in tgmath.h.Joseph Myers1-1/+1
* math/tgmath.h [__GLIBC_USE (IEC_60559_BFP_EXT)] (llogb): Add preprocessor indentation inside #if.
2016-12-20Replace use of snprintf with strfrom in libm testsGabriel F. T. Gomes4-42/+51
In order to support float128 tests, the calls to snprintf, which does not support the type __float128, are replaced with calls to strfrom{f,d,l}. Tested for powerpc64le, s390, and x64_64.
2016-12-20Add fmaxmag, fminmag functions.Joseph Myers8-4/+342
TS 18661-1 defines fmaxmag and fminmag functions that return the argument with maximum / minimum magnitude (acting like fmax / fmin if the arguments have the same magnitude or either argument is a NaN). These correspond to the IEEE 754-2008 operations maxNumMag and minNumMag. This patch implements these functions for glibc. They are implemented with type-generic templates. Tests are based on those for fmax and fmin. Tested for x86_64, x86, mips64 and powerpc. * math/bits/mathcalls.h [__GLIBC_USE (IEC_60559_BFP_EXT)] (fmaxmag): New declaration. (fminmag): Likewise. * math/tgmath.h [__GLIBC_USE (IEC_60559_BFP_EXT)] (fmaxmag): New macro. [__GLIBC_USE (IEC_60559_BFP_EXT)] (fminmag): Likewise. * math/Versions (fmaxmag): New libm symbol at version GLIBC_2.25. (fmaxmagf): Likewise. (fmaxmagl): Likewise. (fminmag): Likewise. (fminmagf): Likewise. (fminmagl): Likewise. * math/Makefile (gen-libm-calls): Add s_fmaxmagF and s_fminmagF. * math/s_fmaxmag_template.c: New file. * math/s_fminmag_template.c: Likewise. * math/libm-test.inc (fmaxmag_test_data): New array. (fmaxmag_test): New function. (fminmag_test_data): New array. (fminmag_test): New function. (main): Call fmaxmag_test and fminmag_test. * math/test-tgmath.c (NCALLS): Increase to 132. (F(compile_test)): Call fmaxmag and fminmag. (F(fminmag)): New function. (F(fmaxmag)): Likewise. * manual/arith.texi (Misc FP Arithmetic): Document fminmag, fminmagf, fminmagl, fmaxmag, fmaxmagf and fmaxmagl. * manual/libm-err-tab.pl (@all_functions): Add fmaxmag and fminmag. * sysdeps/ieee754/ldbl-opt/nldbl-fmaxmag.c: New file. * sysdeps/ieee754/ldbl-opt/nldbl-fminmag.c: Likewise. * sysdeps/ieee754/ldbl-opt/s_fmaxmagl.c: Likewise. * sysdeps/ieee754/ldbl-opt/s_fminmagl.c: Likewise. * sysdeps/ieee754/ldbl-opt/Makefile (libnldbl-calls): Add fmaxmag and fminmag. (CFLAGS-nldbl-fmaxmag.c): New variable. (CFLAGS-nldbl-fminmag.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.
2016-12-16Define FE_SNANS_ALWAYS_SIGNAL.Joseph Myers3-1/+50
TS 18661-1 defines a macro FE_SNANS_ALWAYS_SIGNAL in <fenv.h>, to indicate that the recommended practice regarding sNaNs (that operations always produce a qNaN output with "invalid" exception, even in the fmax / fmin / hypot / pow cases where a qNaN input would not result in qNaN output) is followed. Now that those functions with C99 special cases for NaNs have been fixed not to apply those special cases to sNaN, only to qNaN, glibc follows that recommended practice. This patch makes it define the corresponding macro. Since compiler optimizations may affect whether sNaNs behave as expected and the macro relates to both language and library features, it is only defined if __SUPPORT_SNAN__ is defined (which GCC defines for -fsignaling-nans). It is also not defined if FE_INVALID is undefined, since the recommended practice specifically refers to raising the "invalid" exception, so it seems inappropriate to define the macro for soft-float cases without support for exceptions. (Further refinement would be possible in cases where bits/fenv.h is shared by configurations both with and without exceptions support.) Tested for x86_64 and x86, and also did compile-only testing for nios2 to cover the no-exceptions case. * math/fenv.h [__GLIBC_USE (IEC_60559_BFP_EXT) && FE_INVALID && __SUPPORT_SNAN__] (FE_SNANS_ALWAYS_SIGNAL): New macro. * math/test-fe-snans-always-signal.c: New file. * math/Makefile (tests): Add test-fe-snans-always-signal. (CFLAGS-test-fe-snans-always-signal.c): New variable. * manual/arith.texi (Infinity and NaN): Document FE_SNANS_ALWAYS_SIGNAL.
2016-12-16Make w_scalbln type-genericGabriel F. T. Gomes4-83/+12
This patch converts the wrapper scalbln (which set errno directly rather than doing anything with __kernel_standard) to use the type-generic template machinery, in the same way that has been done for ldexp. Tested for powerpc64le, s390, and x86_64.
2016-12-15Fix x86, x86_64 fmax, fmin sNaN handling, add tests (bug 20947).Joseph Myers1-0/+72
Various fmax and fmin function implementations mishandle sNaN arguments: (a) When both arguments are NaNs, the return value should be a qNaN, but sometimes it is an sNaN if at least one argument is an sNaN. (b) Under TS 18661-1 semantics, if either argument is an sNaN then the result should be a qNaN (whereas if one argument is a qNaN and the other is not a NaN, the result should be the non-NaN argument). Various implementations treat sNaNs like qNaNs here. This patch fixes the x86 and x86_64 versions (ignoring float and double for 32-bit x86 given the inability to reliably avoid the sNaN turning into a qNaN before it gets to the called function). Tests of sNaN inputs to these functions are added. Note on architecture versions I haven't changed for this issue: AArch64 already gets this right (it uses a hardware instruction with the correct semantics for both quiet and signaling NaNs) and does not need changes. It's possible Alpha, IA64, SPARC might need changes (this would be shown by the testsuite if so). Tested for x86_64 and x86 (both i686 and i586 builds, to cover the different x86 implementations). [BZ #20947] * sysdeps/i386/fpu/s_fmaxl.S (__fmaxl): Add the arguments when either is a signaling NaN. * sysdeps/i386/fpu/s_fminl.S (__fminl): Likewise. Make code follow fmaxl more closely. * sysdeps/i386/i686/fpu/s_fmaxl.S (__fmaxl): Add the arguments when either is a signaling NaN. * sysdeps/i386/i686/fpu/s_fminl.S (__fminl): Likewise. * sysdeps/x86_64/fpu/s_fmax.S (__fmax): Likewise. * sysdeps/x86_64/fpu/s_fmaxf.S (__fmaxf): Likewise. * sysdeps/x86_64/fpu/s_fmaxl.S (__fmaxl): Likewise. * sysdeps/x86_64/fpu/s_fmin.S (__fmin): Likewise. * sysdeps/x86_64/fpu/s_fminf.S (__fminf): Likewise. * sysdeps/x86_64/fpu/s_fminl.S (__fminl): Likewise. * math/libm-test.inc (fmax_test_data): Add tests of sNaN inputs. (fmin_test_data): Likewise.
2016-12-14Fix generic fmax, fmin sNaN handling (bug 20947).Joseph Myers2-2/+16
Various fmax and fmin function implementations mishandle sNaN arguments: (a) When both arguments are NaNs, the return value should be a qNaN, but sometimes it is an sNaN if at least one argument is an sNaN. (b) Under TS 18661-1 semantics, if either argument is an sNaN then the result should be a qNaN (whereas if one argument is a qNaN and the other is not a NaN, the result should be the non-NaN argument). Various implementations treat sNaNs like qNaNs here. This patch fixes the generic implementations used in the absence of architecture-specific versions. Tested for mips64 and powerpc (together with testcases that I'll add along with the x86_64 / x86 fixes). [BZ #20947] * math/s_fmax_template.c (M_DECL_FUNC (__fmax)): Add the arguments when either is a signaling NaN. * math/s_fmin_template.c (M_DECL_FUNC (__fmin)): Likewise.
2016-12-14Refactor long double information into bits/long-double.h.Joseph Myers2-5/+2
Information about whether the ABI of long double is the same as that of double is split between bits/mathdef.h and bits/wordsize.h. When the ABIs are the same, bits/mathdef.h defines __NO_LONG_DOUBLE_MATH. In addition, in the case where the same glibc binary supports both -mlong-double-64 and -mlong-double-128, bits/wordsize.h defines __LONG_DOUBLE_MATH_OPTIONAL, along with __NO_LONG_DOUBLE_MATH if this particular compilation is with -mlong-double-64. As part of the refactoring I proposed in <https://sourceware.org/ml/libc-alpha/2016-11/msg00745.html>, this patch puts all that information in a single header, bits/long-double.h. It is included from sys/cdefs.h alongside the include of bits/wordsize.h, so other headers generally do not need to include bits/long-double.h directly. Previously, various bits/mathdef.h headers and bits/wordsize.h headers had this long double information (including implicitly in some bits/mathdef.h headers through not having the defines present in the default version). After the patch, it's all in six bits/long-double.h headers. Furthermore, most of those new headers are not architecture-specific. Architectures with optional long double all use the ldbl-opt sysdeps directory, either in the order (ldbl-64-128, ldbl-opt, ldbl-128) or (ldbl-128ibm, ldbl-opt). Thus a generic header for the case where long double = double, and headers in ldbl-128, ldbl-96 and ldbl-opt, suffices to cover every architecture except for cases where long double properties vary between different ABIs sharing a set of installed headers; fortunately all the ldbl-opt cases share a single compiler-predefined macro __LONG_DOUBLE_128__ that can be used to tell whether this compilation is -mlong-double-64 or -mlong-double-128. The two cases where a set of headers is shared between ABIs with different long double properties, MIPS (o32 has long double = double, other ABIs use ldbl-128) and SPARC (32-bit has optional long double, 64-bit has required long double), need their own bits/long-double.h headers. As with bits/wordsize.h, multiple-include protection for this header is generally implicit through the include guards on sys/cdefs.h, and multiple inclusion is harmless in any case. There is one subtlety: the header must not define __LONG_DOUBLE_MATH_OPTIONAL if __NO_LONG_DOUBLE_MATH was defined before its inclusion, because doing so breaks how sysdeps/ieee754/ldbl-opt/nldbl-compat.h defines __NO_LONG_DOUBLE_MATH itself before including system headers. Subject to keeping that working, it would be reasonable to move these macros from defined/undefined #ifdef to always-defined 1/0 #if semantics, but this patch does not attempt to do so, just rearranges where the macros are defined. After this patch, the only use of bits/mathdef.h is the alpha one for modifying complex function ABIs for old GCC. Thus, all versions of the header other than the default and alpha versions are removed, as is the include from math.h. Tested for x86_64 and x86. Also did compilation-only testing with build-many-glibcs.py. * bits/long-double.h: New file. * sysdeps/ieee754/ldbl-128/bits/long-double.h: Likewise. * sysdeps/ieee754/ldbl-96/bits/long-double.h: Likewise. * sysdeps/ieee754/ldbl-opt/bits/long-double.h: Likewise. * sysdeps/mips/bits/long-double.h: Likewise. * sysdeps/unix/sysv/linux/sparc/bits/long-double.h: Likewise. * math/Makefile (headers): Add bits/long-double.h. * misc/sys/cdefs.h: Include <bits/long-double.h>. * stdlib/strtold.c: Include <bits/long-double.h> instead of <bits/wordsize.h>. * bits/mathdef.h [!_COMPLEX_H]: Do not allow inclusion. [!__NO_LONG_DOUBLE_MATH]: Remove conditional code. * math/math.h: Do not include <bits/mathdef.h>. * sysdeps/aarch64/bits/mathdef.h: Remove file. * sysdeps/alpha/bits/mathdef.h [!_COMPLEX_H]: Do not allow inclusion. * sysdeps/ia64/bits/mathdef.h: Remove file. * sysdeps/m68k/m680x0/bits/mathdef.h: Likewise. * sysdeps/mips/bits/mathdef.h: Likewise. * sysdeps/powerpc/bits/mathdef.h: Likewise. * sysdeps/s390/bits/mathdef.h: Likewise. * sysdeps/sparc/bits/mathdef.h: Likewise. * sysdeps/x86/bits/mathdef.h: Likewise. * sysdeps/s390/s390-32/bits/wordsize.h [!__NO_LONG_DOUBLE_MATH && !__LONG_DOUBLE_MATH_OPTIONAL]: Remove conditional code. * sysdeps/s390/s390-64/bits/wordsize.h [!__NO_LONG_DOUBLE_MATH && !__LONG_DOUBLE_MATH_OPTIONAL]: Likewise. * sysdeps/unix/sysv/linux/alpha/bits/wordsize.h [!__NO_LONG_DOUBLE_MATH && !__LONG_DOUBLE_MATH_OPTIONAL]: Likewise. * sysdeps/unix/sysv/linux/powerpc/bits/wordsize.h [!__NO_LONG_DOUBLE_MATH && !__LONG_DOUBLE_MATH_OPTIONAL]: Likewise. * sysdeps/unix/sysv/linux/sparc/bits/wordsize.h [!__NO_LONG_DOUBLE_MATH && !__LONG_DOUBLE_MATH_OPTIONAL]: Likewise.
2016-12-14Make w_log1p type-genericGabriel F. T. Gomes4-85/+9
This patch converts the wrapper log1p (which set errno directly rather than doing anything with __kernel_standard) to use the type-generic template machinery, in the same way that has been done for ilogb. Tested for powerpc64le, s390, and x86_64.
2016-12-13Better design of libm.a installation rule.Andrew Senkevich1-4/+7
* math/Makefile ($(inst_libdir)/libm-$(version).a): New target. * ($(inst_libdir)/libm.a): Fix rule to create the target only.
2016-12-08Install libm.a as linker script (bug 20539).Andrew Senkevich1-4/+15
Install libm.a as linker script to avoid static link fail w/o passing additional -lmvec option while building with GCC >= 6.1. [BZ #20539] * math/Makefile (install-lib-ldscripts): Add libm.a. (install_subdir): Remove. (install-others): Add. ($(inst_libdir)/libm.a): Add rule for installation as linker script. * Makerules (install-lib.a): Filter out install-lib-ldscripts.
2016-12-07Fix hypot sNaN handling (bug 20940).Joseph Myers1-0/+52
TS 18661-1 generally defines libm functions taking sNaN arguments to return qNaN and raise "invalid", even for the cases where a corresponding qNaN argument would not result in a qNaN return. This includes hypot with one argument being an infinity and the other being an sNaN. This patch duly fixes hypot implementatations in glibc (generic and powerpc) to ensure qNaN, computed by arithmetic on the arguments, is returned in that case. Various implementations do their checks for infinities and NaNs inline by manipulating the representations of the arguments. For simplicity, this patch just uses issignaling to check for sNaN arguments. This could be inlined like the existing code (with due care about reversed quiet NaN conventions, for implementations where that is relevant), but given that all these checks are in cases where it's already known at least one argument is not finite, which should be the uncommon case, that doesn't seem worthwhile unless performance issues are observed in practice. Tested for x86_64, x86, mips64 and powerpc. [BZ #20940] * sysdeps/ieee754/dbl-64/e_hypot.c (__ieee754_hypot): Do not return Inf for arguments Inf and sNaN. * sysdeps/ieee754/flt-32/e_hypotf.c (__ieee754_hypotf): Likewise. * sysdeps/ieee754/ldbl-128/e_hypotl.c (__ieee754_hypotl): Likewise. * sysdeps/ieee754/ldbl-128ibm/e_hypotl.c (__ieee754_hypotl): Likewise. * sysdeps/ieee754/ldbl-96/e_hypotl.c (__ieee754_hypotl): Likewise. * sysdeps/powerpc/fpu/e_hypot.c (TEST_INF_NAN): Do not return Inf for arguments Inf and sNaN. When returning a NaN, compute it by arithmetic on the arguments. * sysdeps/powerpc/fpu/e_hypotf.c (TEST_INF_NAN): Likewise. * math/libm-test.inc (pow_test_data): Add tests of sNaN arguments.
2016-12-06Fix x86_64/x86 powl handling of sNaN arguments (bug 20916).Joseph Myers1-1/+53
The x86_64/x86 powl implementations mishandle sNaN arguments, both by returning sNaN in some cases (instead of doing arithmetic on the arguments to produce the result when NaN arguments result in NaN results) and by treating sNaN the same as qNaN for arguments (1, sNaN) and (sNaN, 0), contrary to TS 18661-1 which requires those cases to return qNaN instead of 1. This patch makes the x86_64/x86 powl implementations follow TS 18661-1 semantics for sNaN arguments; sNaN tests are also added for pow. Given the problems with testing float and double sNaN arguments on 32-bit x86 (sNaN tests disabled because the compiler may convert unnecessarily to a qNaN when passing arguments), no changes are made to the powf and pow implementations there. Tested for x86_64 and x86. [BZ #20916] * sysdeps/i386/fpu/e_powl.S (__ieee754_powl): Do not return 1 for arguments (sNaN, 0) or (1, sNaN). Do arithmetic on NaN arguments to compute result. * sysdeps/x86_64/fpu/e_powl.S (__ieee754_powl): Likewise. * math/libm-test.inc (pow_test_data): Add tests of sNaN arguments.
2016-12-02Fix pow (qNaN, 0) result with -lieee (bug 20919), remove dead parts of wrappers.Joseph Myers3-57/+15
The dbl-64 implementation of __ieee754_pow returns a NaN for pow (qNaN, 0) when it should return 1. Normally this is covered up by the wrappers ending up calling __kernel_standard which fixes up the result for this case, but for -lieee the wrappers are bypassed and the bad result gets through as a return value. Now, the wrappers fixing this are dealing with variant error handling that wants a result of NaN for pow (qNaN, 0), and only ever call __kernel_standard for this case if NaN resulted from __ieee754_pow. This leads to a question of whether the dbl-64 code might be deliberately returning NaN in order to use those code paths. However, I can find no sign that this is deliberate. If it were deliberate one would expect other implementations to do the same, and would expect the return of NaN to be very old, but it appears it came in by accident when the present e_pow.c implementation replaced an fdlibm implementation in 2001. So it appears to be unintended that this path through the pow wrapper could be used at all. So this patch fixes the implementation to return 1 in this case as expected. This is consistent with all the other implementations. The relevant path through the wrappers is now unreachable, so is removed (which is the main motivation of this patch: to avoid that path becoming accidentally reachable when implementing TS 18661-1 semantics that pow (sNaN, 0) should return qNaN with "invalid" raised). Another path that would require __ieee754_pow (0, 0) to return 0 is also unreachable (as all implementations return 1, in accordance with C99 semantics), so is removed as well. Note: we don't have anything set up to test -lieee, which in any case is obsolescent (at some point we should remove the ability for new programs to access _LIB_VERSION or define matherr and have it called by glibc). So testing will be implicit through sNaN tests added when making sNaN inputs work correctly for pow functions. Tested for x86_64 and x86. [BZ #20919] * sysdeps/ieee754/dbl-64/e_pow.c (__ieee754_pow): Do not return NaN first argument when raised to power 0. * math/w_pow.c (__pow): Do not check for NaN or zero results from raising to power zero. * math/w_powf.c (__powf): Likewise. * math/w_powl.c (__powl): Likewise. * sysdeps/ieee754/k_standard.c (__kernel_standard): Do not handle pow (0, 0) or pow (NaN, 0).
2016-12-02Add llogb, llogbf, llogbl.Joseph Myers10-5/+182
TS 18661-1 defines llogb functions that are like ilogb except that they return long int instead of int. Corresponding FP_LLOGB* macros are defined, whose values are required to have the obvious correspondence to those of the FP_ILOGB* macros. This patch implements these functions and macros for glibc. llogb uses the type-generic infrastructure, with an implementation similar to the wrapper for ilogb but with additional conversion from FP_ILOGB* to FP_LLOGB*; this approach avoids needing to modify or duplicate any of the architecture-specific ilogb implementations. Tests are also based on those for ilogb. Ideally the llogb functions would alias the ilogb ones when long is 32-bit, but such aliasing requires the associated header declarations of the different-type alias to be hidden, typically by defining macros before including the header (see e.g. how sysdeps/ieee754/dbl-64/wordsize-64/s_llround.c defines lround to __hidden_lround before including <math.h>). The infrastructure for type-generic function implementations does not support defining such macros at present (since C code can't define a macro whose name is determined by other macros). So this patch leaves them as separate functions (similar to e.g. scalbln and scalbn being separate in such a case as well), but with the remapping of FP_ILOGB* to FP_LLOGB* conditioned out in the case where it would be the identity map. Tested for x86_64, x86, mips64 and powerpc. * math/bits/mathcalls.h [__GLIBC_USE (IEC_60559_BFP_EXT)] (llogb): New declaration. * math/tgmath.h [__GLIBC_USE (IEC_60559_BFP_EXT)] (llogb): New macro. * math/math.h [__GLIBC_USE (IEC_60559_BFP_EXT)] (__FP_LONG_MAX): New macro. [__GLIBC_USE (IEC_60559_BFP_EXT)] (FP_LLOGB0): Likewise. [__GLIBC_USE (IEC_60559_BFP_EXT)] (FP_LLOGBNAN): Likewise. * math/Versions (llogb): New libm symbol at version GLIBC_2.25. (llogbf): Likewise. (llogbl): Likewise. * math/Makefile (gen-libm-calls): Add w_llogbF. (tests): Add test-fp-llogb-constants. * math/w_llogb_template.c: New file. Based on math/w_ilogb_template.c. * math/libm-test.inc (llogb_test_data): New array. (llogb_test): New function. (main): Call llogb_test. * math/test-fp-llogb-constants.c: New file. Based on math/test-fp-ilogb-constants.c. * math/test-tgmath-ret.c (llogb): New CHECK_RET_CONST call. (do_test): Call check_return_llogb. * math/test-tgmath.c (NCALLS): Increase to 126. (F(compile_test)): Call llogb. (F(llogb)): New function. * manual/math.texi (Exponents and Logarithms): Document llogb, llogbf, llogbl, FP_LLOGB0 and FP_LLOGBNAN. * manual/libm-err-tab.pl (@all_functions): Add llogb. * sysdeps/ieee754/ldbl-opt/nldbl-llogb.c: New file. * sysdeps/ieee754/ldbl-opt/w_llogbl.c: Likewise. * sysdeps/ieee754/ldbl-opt/Makefile (libnldbl-calls): Add llogb. (CFLAGS-nldbl-llogb.c): New variable. * 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.
2016-12-01Refactor FP_ILOGB* out of bits/mathdef.h.Joseph Myers2-2/+19
Continuing the refactoring of bits/mathdef.h, this patch stops it defining FP_ILOGB0 and FP_ILOGBNAN, moving the required information to a new header bits/fp-logb.h. There are only two possible values of each of those macros permitted by ISO C. TS 18661-1 adds corresponding macros for llogb, and their values are required to correspond to those of the ilogb macros in the obvious way. Thus two boolean values - for which the same choices are correct for most architectures - suffice to determine the value of all these macros, and by defining macros for those boolean values in bits/fp-logb.h we can then define the public FP_* macros in math.h and avoid the present duplication of the associated feature test macro logic. This patch duly moves to bits/fp-logb.h defining __FP_LOGB0_IS_MIN and __FP_LOGBNAN_IS_MIN. Default definitions of those to 0 are correct for both architectures, while ia64, m68k and x86 get their own versions of bits/fp-logb.h to reflect their use of values different from the defaults. The patch renders many copies of bits/mathdef.h trivial (needed only to avoid the default __NO_LONG_DOUBLE_MATH). I'll revise <https://sourceware.org/ml/libc-alpha/2016-11/msg00865.html> accordingly so that it removes all bits/mathdef.h headers except the default one and the alpha one, and arranges for the header to be included only by complex.h as the only remaining use at that point will be for the alpha ABI issues there. Tested for x86_64 and x86. Also did compile-only testing with build-many-glibcs.py (using glibc sources from before the commit that introduced many build failures with undefined __GI___sigsetjmp). * bits/fp-logb.h: New file. * sysdeps/ia64/bits/fp-logb.h: Likewise. * sysdeps/m68k/m680x0/bits/fp-logb.h: Likewise. * sysdeps/x86/bits/fp-logb.h: Likewise. * math/Makefile (headers): Add bits/fp-logb.h. * math/math.h: Include <bits/fp-logb.h>. [__USE_ISOC99] (FP_ILOGB0): Define based on __FP_LOGB0_IS_MIN. [__USE_ISOC99] (FP_ILOGBNAN): Define based on __FP_LOGBNAN_IS_MIN. * bits/mathdef.h (FP_ILOGB0): Remove. (FP_ILOGBNAN): Likewise. * sysdeps/aarch64/bits/mathdef.h (FP_ILOGB0): Likewise. (FP_ILOGBNAN): Likewise. * sysdeps/alpha/bits/mathdef.h (FP_ILOGB0): Likewise. (FP_ILOGBNAN): Likewise. * sysdeps/ia64/bits/mathdef.h (FP_ILOGB0): Likewise. (FP_ILOGBNAN): Likewise. * sysdeps/m68k/m680x0/bits/mathdef.h (FP_ILOGB0): Likewise. (FP_ILOGBNAN): Likewise. * sysdeps/mips/bits/mathdef.h (FP_ILOGB0): Likewise. (FP_ILOGBNAN): Likewise. * sysdeps/powerpc/bits/mathdef.h (FP_ILOGB0): Likewise. (FP_ILOGBNAN): Likewise. * sysdeps/s390/bits/mathdef.h (FP_ILOGB0): Likewise. (FP_ILOGBNAN): Likewise. * sysdeps/sparc/bits/mathdef.h (FP_ILOGB0): Likewise. (FP_ILOGBNAN): Likewise. * sysdeps/x86/bits/mathdef.h (FP_ILOGB0): Likewise. (FP_ILOGBNAN): Likewise.
2016-11-29Refactor FP_FAST_* into bits/fp-fast.h.Joseph Myers2-6/+11
Continuing the refactoring of bits/mathdef.h, this patch moves the FP_FAST_* definitions into a new bits/fp-fast.h header. Currently this is only for FP_FAST_FMA*, but in future it would be the appropriate place for the FP_FAST_* macros from TS 18661-1 as well. The generic bits/mathdef.h header defines these macros based on whether the compiler defines __FP_FAST_*. Most architecture-specific headers, however, fail to do so, meaning that if the architecture (or some particular processors) does in fact have fused operations, and GCC knows to use them inline, the FP_FAST_* macros will still not be defined. By refactoring, this patch causes the generic version (based on __FP_FAST_*) to be used in more cases, and so the macro definitions to be more accurate. Architectures that already defined some or all of these macros other than based on the predefines have their own versions of fp-fast.h, which are arranged so they define FP_FAST_* if either the architecture-specific conditions are true or __FP_FAST_* are defined. After this refactoring, various bits/mathdef.h headers for architectures with long double = double are semantically identical to the generic version. The patch removes those headers that are redundant. (In fact two of the four removed were already redundant before this patch because they did use __FP_FAST_*.) Tested for x86_64 and x86, and compilation-only with build-many-glibcs.py. * bits/fp-fast.h: New file. * sysdeps/aarch64/bits/fp-fast.h: Likewise. * sysdeps/powerpc/bits/fp-fast.h: Likewise. * math/Makefile (headers): Add bits/fp-fast.h. * math/math.h: Include <bits/fp-fast.h>. * bits/mathdef.h (FP_FAST_FMA): Remove. (FP_FAST_FMAF): Likewise. (FP_FAST_FMAL): Likewise. * sysdeps/aarch64/bits/mathdef.h (FP_FAST_FMA): Likewise. (FP_FAST_FMAF): Likewise. * sysdeps/powerpc/bits/mathdef.h (FP_FAST_FMA): Likewise. (FP_FAST_FMAF): Likewise. * sysdeps/x86/bits/mathdef.h (FP_FAST_FMA): Likewise. (FP_FAST_FMAF): Likewise. (FP_FAST_FMAL): Likewise. * sysdeps/arm/bits/mathdef.h: Remove file. * sysdeps/hppa/fpu/bits/mathdef.h: Likewise. * sysdeps/sh/sh4/bits/mathdef.h: Likewise. * sysdeps/tile/bits/mathdef.h: Likewise.
2016-11-28Make ilogb wrappers type-generic.Joseph Myers4-86/+9
This patch converts the ilogb wrappers (which set errno directly rather than doing anything with __kernel_standard) to use the type-generic template machinery. This is intended as preparation for adding llogb. Tested for x86_64 and x86, and tested compile for other architectures with build-many-glibcs.py. * math/w_ilogb_template.c: New file. Based on math/w_ilogb.c. * math/w_ilogb.c: Remove. * math/w_ilogbf.c: Likewise. * math/w_ilogbl.c: Likewise. * sysdeps/ieee754/ldbl-opt/w_ilogb.c: Likewise. * sysdeps/ieee754/ldbl-opt/w_ilogbl.c: Likewise. * math/Makefile (gen-libm-calls): Add w_ilogbF. (libm-calls): Remove w_ilogbF. * sysdeps/ieee754/ldbl-opt/math-type-macros-double.h (LDOUBLE_ilogbl_libm_version): New macro.
2016-11-24Add setpayloadsig, setpayloadsigf, setpayloadsigl.Joseph Myers4-2/+93