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* Fix powf overflow handling in non-nearest rounding mode [BZ #23961]Szabolcs Nagy2018-12-111-0/+12
| | | | | | | | | | | | | | | | | | | | | | | | | | The threshold value at which powf overflows depends on the rounding mode and the current check did not take this into account. So when the result was rounded away from zero it could become infinity without setting errno to ERANGE. Example: pow(0x1.7ac7cp+5, 23) is 0x1.fffffep+127 + 0.1633ulp If the result goes above 0x1.fffffep+127 + 0.5ulp then errno is set, which is fine in nearest rounding mode, but powf(0x1.7ac7cp+5, 23) is inf in upward rounding mode powf(-0x1.7ac7cp+5, 23) is -inf in downward rounding mode and the previous implementation did not set errno in these cases. The fix tries to avoid affecting the common code path or calling a function that may introduce a stack frame, so float arithmetics is used to check the rounding mode and the threshold is selected accordingly. [BZ #23961] * math/auto-libm-test-in: Add new test case. * math/auto-libm-test-out-pow: Regenerated. * sysdeps/ieee754/flt-32/e_powf.c (__powf): Fix overflow check.
* Fix the documentation comment of checkint in powfSzabolcs Nagy2018-09-191-1/+2
| | | | | | checkint in powf is not supposed to be used with 0, inf or nan inputs. * sysdeps/ieee754/flt-32/e_powf.c (checkint): Fix documentation.
* Use uint32_t sign in single precision math error handling functionsSzabolcs Nagy2018-07-021-2/+2
| | | | | | | | | | | | | | | | | | | | | Ideally sign should be bool, but sometimes (e.g. in powf) it's more efficient to pass a non-zero value than 1 to indicate that the sign should be set. The fixed size int is less ambigous than unsigned long. * sysdeps/ieee754/flt-32/e_powf.c (__powf): Use uint32_t. (exp2f_inline): Likewise. * sysdeps/ieee754/flt-32/math_config.h (__math_oflowf): Likewise. (__math_uflowf): Likewise. (__math_may_uflowf): Likewise. (__math_divzerof): Likewise. (__math_invalidf): Likewise. * sysdeps/ieee754/flt-32/math_errf.c (xflowf): Likewise. (__math_oflowf): Likewise. (__math_uflowf): Likewise. (__math_may_uflowf): Likewise. (__math_divzerof): Likewise. (__math_invalidf): Likewise.
* Update copyright dates with scripts/update-copyrights.Joseph Myers2018-01-011-1/+1
| | | | | | | * All files with FSF copyright notices: Update copyright dates using scripts/update-copyrights. * locale/programs/charmap-kw.h: Regenerated. * locale/programs/locfile-kw.h: Likewise.
* Add libm_alias_*_other_r macros.Joseph Myers2017-10-101-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Some libm functions are unable to use the generic alias macros such as libm_alias_double because they have special symbol versioning requirements for the main float, double or long double public names. To facilitate adding _FloatN / _FloatNx function aliases in future, it's still desirable to have generic macros those functions can use as far as possible. This patch adds macros such as libm_alias_double_other, which only define names for _FloatN / _FloatNx aliases, not for float / double / long double. As present, all these new macros do nothing, but they are called in the appropriate places in macros such as libm_alias_double. This patch also arranges for lgamma implementations, and the recently added optimized float function implementations, to use the new macros to make them ready for addition of _FloatN / _FloatNx aliases. Tested for x86_64, and tested with build-many-glibcs.py that installed stripped shared libraries are unchanged by this patch. * sysdeps/generic/libm-alias-double.h (libm_alias_double_other_r): New macro. (libm_alias_double_other): Likewise. (libm_alias_double_r): Use libm_alias_double_other_r. * sysdeps/generic/libm-alias-float.h (libm_alias_float_other_r): New macro. (libm_alias_float_other): Likewise. (libm_alias_float_r): Use libm_alias_float_other_r. * sysdeps/generic/libm-alias-float128.h (libm_alias_float128_other_r): New macro. (libm_alias_float128_other): Likewise. (libm_alias_float128_r): Use libm_alias_float128_other_r. * sysdeps/generic/libm-alias-ldouble.h (libm_alias_ldouble_other_r): New macro. (libm_alias_ldouble_other): Likewise. (libm_alias_ldouble_r): Use libm_alias_ldouble_other_r. * sysdeps/ieee754/ldbl-opt/libm-alias-double.h (libm_alias_double_other_r): New macro. (libm_alias_double_other): Likewise. (libm_alias_double_r): Use libm_alias_double_other_r. * sysdeps/ieee754/ldbl-opt/libm-alias-ldouble.h (libm_alias_ldouble_other_r): New macro. (libm_alias_ldouble_other): Likewise. (libm_alias_ldouble_r): Use libm_alias_ldouble_other_r. * math/w_lgamma_main.c: Include <libm-alias-double.h>. [!USE_AS_COMPAT]: Use libm_alias_double_other. * math/w_lgammaf_main.c: Include <libm-alias-float.h>. [!USE_AS_COMPAT]: Use libm_alias_float_other. * math/w_lgammal_main.c: Include <libm-alias-ldouble.h>. [!USE_AS_COMPAT]: Use libm_alias_ldouble_other. * math/w_exp2f.c: Use libm_alias_float_other. * math/w_expf.c: Likewise. * math/w_log2f.c: Likewise. * math/w_logf.c: Likewise. * math/w_powf.c: Likewise. * sysdeps/ieee754/flt-32/e_exp2f.c: Include <libm-alias-float.h>. [!__exp2f]: Use libm_alias_float_other. * sysdeps/ieee754/flt-32/e_expf.c: Include <libm-alias-float.h>. [!__expf]: Use libm_alias_float_other. * sysdeps/ieee754/flt-32/e_log2f.c: Include <libm-alias-float.h>. [!__log2f]: Use libm_alias_float_other. * sysdeps/ieee754/flt-32/e_logf.c: Include <libm-alias-float.h>. [!__logf]: Use libm_alias_float_other. * sysdeps/ieee754/flt-32/e_powf.c: Include <libm-alias-float.h>. [!__powf]: Use libm_alias_float_other.
* Do not wrap logf, log2f and powfSzabolcs Nagy2017-10-021-2/+7
| | | | | | | | | | | | | | | | | | The new generic logf, log2f and powf code don't need wrappers any more, they set errno inline so only use the wrappers on targets that need it. * sysdeps/ieee754/flt-32/e_log2f.c (__log2f): Define without wrapper. * sysdeps/ieee754/flt-32/e_logf.c (__logf): Likewise * sysdeps/ieee754/flt-32/e_powf.c (__powf): Likewise * sysdeps/ieee754/flt-32/w_log2f.c: New file. * sysdeps/ieee754/flt-32/w_logf.c: New file. * sysdeps/ieee754/flt-32/w_powf.c: New file. * sysdeps/i386/fpu/w_log2f.c: New file. * sysdeps/i386/fpu/w_logf.c: New file. * sysdeps/i386/fpu/w_powf.c: New file. * sysdeps/m68k/m680x0/fpu/w_log2f.c: New file. * sysdeps/m68k/m680x0/fpu/w_logf.c: New file. * sysdeps/m68k/m680x0/fpu/w_powf.c: New file.
* New generic powfSzabolcs Nagy2017-09-291-199/+189
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | without wrapper on aarch64: powf reciprocal-throughput: 4.2x faster powf latency: 2.6x faster old worst-case error: 1.11 ulp new worst-case error: 0.82 ulp aarch64 .text size: -780 bytes aarch64 .rodata size: +144 bytes powf(x,y) is implemented as exp2(y*log2(x)) with the same algorithms that are used in exp2f and log2f, except that the log2f polynomial is larger for extra precision and its output (and exp2f input) may be scaled by a power of 2 (POWF_SCALE) to simplify the argument reduction step of exp2 (possible when efficient round and convert toint operation is available). The special case handling tries to minimize the checks in the hot path. When the input of exp2_inline is checked, int arithmetics is used as that was faster on the tested aarch64 cores. * math/Makefile (type-float-routines): Add e_powf_log2_data. * sysdeps/ieee754/flt-32/e_powf.c: New implementation. * sysdeps/ieee754/flt-32/e_powf_log2_data.c: New file. * sysdeps/ieee754/flt-32/math_config.h (__powf_log2_data): Define. (issignalingf_inline): Likewise. (POWF_LOG2_TABLE_BITS): Likewise. (POWF_LOG2_POLY_ORDER): Likewise. (POWF_SCALE_BITS): Likewise. (POWF_SCALE): Likewise. * sysdeps/i386/fpu/e_powf_log2_data.c: New file. * sysdeps/ia64/fpu/e_powf_log2_data.c: New file. * sysdeps/m68k/m680x0/fpu/e_powf_log2_data.c: New file.
* Consistently use uintN_t not u_intN_t in libm.Joseph Myers2017-08-031-3/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch changes libm code to make consistent use of C99 uintN_t types instead of sometimes using those and sometimes using the older nonstandard u_intN_t names. This makes sense as a cleanup in its own right, and also facilitates merges to GCC's libquadmath (which gets the types from stdint.h and so may not have u_intN_t available at all). Tested for x86_64, and with build-many-glibcs.py. * math/s_nextafter.c (__nextafter): Use uintN_t instead of u_intN_t. * math/s_nexttowardf.c (__nexttowardf): Likewise. * sysdeps/generic/math_private.h (ieee_double_shape_type): Likewise. (ieee_float_shape_type): Likewise. * sysdeps/i386/fpu/s_fpclassifyl.c (__fpclassifyl): Likewise. * sysdeps/i386/fpu/s_isnanl.c (__isnanl): Likewise. * sysdeps/i386/fpu/s_nextafterl.c (__nextafterl): Likewise. * sysdeps/i386/fpu/s_nexttoward.c (__nexttoward): Likewise. * sysdeps/i386/fpu/s_nexttowardf.c (__nexttowardf): Likewise. * sysdeps/ieee754/dbl-64/e_acosh.c (__ieee754_acosh): Likewise. * sysdeps/ieee754/dbl-64/e_cosh.c (__ieee754_cosh): Likewise. * sysdeps/ieee754/dbl-64/e_fmod.c (__ieee754_fmod): Likewise. * sysdeps/ieee754/dbl-64/e_gamma_r.c (__ieee754_gamma_r): Likewise. * sysdeps/ieee754/dbl-64/e_hypot.c (__ieee754_hypot): Likewise. * sysdeps/ieee754/dbl-64/e_jn.c (__ieee754_jn): Likewise. (__ieee754_yn): Likewise. * sysdeps/ieee754/dbl-64/e_log10.c (__ieee754_log10): Likewise. * sysdeps/ieee754/dbl-64/e_log2.c (__ieee754_log2): Likewise. * sysdeps/ieee754/dbl-64/e_rem_pio2.c (__ieee754_rem_pio2): Likewise. * sysdeps/ieee754/dbl-64/e_sinh.c (__ieee754_sinh): Likewise. * sysdeps/ieee754/dbl-64/s_ceil.c (__ceil): Likewise. * sysdeps/ieee754/dbl-64/s_copysign.c (__copysign): Likewise. * sysdeps/ieee754/dbl-64/s_erf.c (__erf): Likewise. (__erfc): Likewise. * sysdeps/ieee754/dbl-64/s_expm1.c (__expm1): Likewise. * sysdeps/ieee754/dbl-64/s_finite.c (FINITE): Likewise. * sysdeps/ieee754/dbl-64/s_floor.c (__floor): Likewise. * sysdeps/ieee754/dbl-64/s_fpclassify.c (__fpclassify): Likewise. * sysdeps/ieee754/dbl-64/s_isnan.c (__isnan): Likewise. * sysdeps/ieee754/dbl-64/s_issignaling.c (__issignaling): Likewise. * sysdeps/ieee754/dbl-64/s_llrint.c (__llrint): Likewise. * sysdeps/ieee754/dbl-64/s_llround.c (__llround): Likewise. * sysdeps/ieee754/dbl-64/s_lrint.c (__lrint): Likewise. * sysdeps/ieee754/dbl-64/s_lround.c (__lround): Likewise. * sysdeps/ieee754/dbl-64/s_modf.c (__modf): Likewise. * sysdeps/ieee754/dbl-64/s_nextup.c (__nextup): Likewise. * sysdeps/ieee754/dbl-64/s_remquo.c (__remquo): Likewise. * sysdeps/ieee754/dbl-64/s_round.c (__round): Likewise. * sysdeps/ieee754/dbl-64/s_trunc.c (__trunc): Likewise. * sysdeps/ieee754/dbl-64/wordsize-64/s_issignaling.c (__issignaling): Likewise. * sysdeps/ieee754/flt-32/e_atan2f.c (__ieee754_atan2f): Likewise. * sysdeps/ieee754/flt-32/e_fmodf.c (__ieee754_fmodf): Likewise. * sysdeps/ieee754/flt-32/e_gammaf_r.c (__ieee754_gammaf_r): Likewise. * sysdeps/ieee754/flt-32/e_jnf.c (__ieee754_ynf): Likewise. * sysdeps/ieee754/flt-32/e_log10f.c (__ieee754_log10f): Likewise. * sysdeps/ieee754/flt-32/e_powf.c (__ieee754_powf): Likewise. * sysdeps/ieee754/flt-32/e_rem_pio2f.c (__ieee754_rem_pio2f): Likewise. * sysdeps/ieee754/flt-32/e_remainderf.c (__ieee754_remainderf): Likewise. * sysdeps/ieee754/flt-32/e_sqrtf.c (__ieee754_sqrtf): Likewise. * sysdeps/ieee754/flt-32/s_ceilf.c (__ceilf): Likewise. * sysdeps/ieee754/flt-32/s_copysignf.c (__copysignf): Likewise. * sysdeps/ieee754/flt-32/s_erff.c (__erff): Likewise. (__erfcf): Likewise. * sysdeps/ieee754/flt-32/s_expm1f.c (__expm1f): Likewise. * sysdeps/ieee754/flt-32/s_finitef.c (FINITEF): Likewise. * sysdeps/ieee754/flt-32/s_floorf.c (__floorf): Likewise. * sysdeps/ieee754/flt-32/s_fpclassifyf.c (__fpclassifyf): Likewise. * sysdeps/ieee754/flt-32/s_isnanf.c (__isnanf): Likewise. * sysdeps/ieee754/flt-32/s_issignalingf.c (__issignalingf): Likewise. * sysdeps/ieee754/flt-32/s_llrintf.c (__llrintf): Likewise. * sysdeps/ieee754/flt-32/s_llroundf.c (__llroundf): Likewise. * sysdeps/ieee754/flt-32/s_lrintf.c (__lrintf): Likewise. * sysdeps/ieee754/flt-32/s_lroundf.c (__lroundf): Likewise. * sysdeps/ieee754/flt-32/s_modff.c (__modff): Likewise. * sysdeps/ieee754/flt-32/s_remquof.c (__remquof): Likewise. * sysdeps/ieee754/flt-32/s_roundf.c (__roundf): Likewise. * sysdeps/ieee754/ldbl-128/e_acoshl.c (__ieee754_acoshl): Likewise. * sysdeps/ieee754/ldbl-128/e_atan2l.c (__ieee754_atan2l): Likewise. * sysdeps/ieee754/ldbl-128/e_atanhl.c (__ieee754_atanhl): Likewise. * sysdeps/ieee754/ldbl-128/e_fmodl.c (__ieee754_fmodl): Likewise. * sysdeps/ieee754/ldbl-128/e_gammal_r.c (__ieee754_gammal_r): Likewise. * sysdeps/ieee754/ldbl-128/e_hypotl.c (__ieee754_hypotl): Likewise. * sysdeps/ieee754/ldbl-128/e_jnl.c (__ieee754_jnl): Likewise. (__ieee754_ynl): Likewise. * sysdeps/ieee754/ldbl-128/e_powl.c (__ieee754_powl): Likewise. * sysdeps/ieee754/ldbl-128/e_rem_pio2l.c (__ieee754_rem_pio2l): Likewise. * sysdeps/ieee754/ldbl-128/e_remainderl.c (__ieee754_remainderl): Likewise. * sysdeps/ieee754/ldbl-128/e_sinhl.c (__ieee754_sinhl): Likewise. * sysdeps/ieee754/ldbl-128/k_cosl.c (__kernel_cosl): Likewise. * sysdeps/ieee754/ldbl-128/k_sincosl.c (__kernel_sincosl): Likewise. * sysdeps/ieee754/ldbl-128/k_sinl.c (__kernel_sinl): Likewise. * sysdeps/ieee754/ldbl-128/s_ceill.c (__ceill): Likewise. * sysdeps/ieee754/ldbl-128/s_copysignl.c (__copysignl): Likewise. * sysdeps/ieee754/ldbl-128/s_erfl.c (__erfcl): Likewise. * sysdeps/ieee754/ldbl-128/s_fabsl.c (__fabsl): Likewise. * sysdeps/ieee754/ldbl-128/s_finitel.c (__finitel): Likewise. * sysdeps/ieee754/ldbl-128/s_floorl.c (__floorl): Likewise. * sysdeps/ieee754/ldbl-128/s_fpclassifyl.c (__fpclassifyl): Likewise. * sysdeps/ieee754/ldbl-128/s_frexpl.c (__frexpl): Likewise. * sysdeps/ieee754/ldbl-128/s_isnanl.c (__isnanl): Likewise. * sysdeps/ieee754/ldbl-128/s_issignalingl.c (__issignalingl): Likewise. * sysdeps/ieee754/ldbl-128/s_llrintl.c (__llrintl): Likewise. * sysdeps/ieee754/ldbl-128/s_llroundl.c (__llroundl): Likewise. * sysdeps/ieee754/ldbl-128/s_lrintl.c (__lrintl): Likewise. * sysdeps/ieee754/ldbl-128/s_lroundl.c (__lroundl): Likewise. * sysdeps/ieee754/ldbl-128/s_modfl.c (__modfl): Likewise. * sysdeps/ieee754/ldbl-128/s_nearbyintl.c (__nearbyintl): Likewise. * sysdeps/ieee754/ldbl-128/s_nextafterl.c (__nextafterl): Likewise. * sysdeps/ieee754/ldbl-128/s_nexttoward.c (__nexttoward): Likewise. * sysdeps/ieee754/ldbl-128/s_nexttowardf.c (__nexttowardf): Likewise. * sysdeps/ieee754/ldbl-128/s_nextupl.c (__nextupl): Likewise. * sysdeps/ieee754/ldbl-128/s_remquol.c (__remquol): Likewise. * sysdeps/ieee754/ldbl-128/s_rintl.c (__rintl): Likewise. * sysdeps/ieee754/ldbl-128/s_roundl.c (__roundl): Likewise. * sysdeps/ieee754/ldbl-128/s_tanhl.c (__tanhl): Likewise. * sysdeps/ieee754/ldbl-128/s_truncl.c (__truncl): Likewise. * sysdeps/ieee754/ldbl-128ibm/e_fmodl.c (__ieee754_fmodl): Likewise. * sysdeps/ieee754/ldbl-128ibm/e_gammal_r.c (__ieee754_gammal_r): Likewise. * sysdeps/ieee754/ldbl-128ibm/e_powl.c (__ieee754_powl): Likewise. * sysdeps/ieee754/ldbl-128ibm/e_rem_pio2l.c (__ieee754_rem_pio2l): Likewise. * sysdeps/ieee754/ldbl-128ibm/e_remainderl.c (__ieee754_remainderl): Likewise. * sysdeps/ieee754/ldbl-128ibm/k_cosl.c (__kernel_cosl): Likewise. * sysdeps/ieee754/ldbl-128ibm/k_sinl.c (__kernel_sinl): Likewise. * sysdeps/ieee754/ldbl-128ibm/s_fabsl.c (__fabsl): Likewise. * sysdeps/ieee754/ldbl-128ibm/s_fpclassifyl.c (___fpclassifyl): Likewise. * sysdeps/ieee754/ldbl-128ibm/s_modfl.c (__modfl): Likewise. * sysdeps/ieee754/ldbl-128ibm/s_nexttowardf.c (__nexttowardf): Likewise. * sysdeps/ieee754/ldbl-128ibm/s_remquol.c (__remquol): Likewise. * sysdeps/ieee754/ldbl-96/e_acoshl.c (__ieee754_acoshl): Likewise. * sysdeps/ieee754/ldbl-96/e_asinl.c (__ieee754_asinl): Likewise. * sysdeps/ieee754/ldbl-96/e_atanhl.c (__ieee754_atanhl): Likewise. * sysdeps/ieee754/ldbl-96/e_coshl.c (__ieee754_coshl): Likewise. * sysdeps/ieee754/ldbl-96/e_gammal_r.c (__ieee754_gammal_r): Likewise. * sysdeps/ieee754/ldbl-96/e_hypotl.c (__ieee754_hypotl): Likewise. * sysdeps/ieee754/ldbl-96/e_j0l.c (__ieee754_j0l): Likewise. (__ieee754_y0l): Likewise. (pzero): Likewise. (qzero): Likewise. * sysdeps/ieee754/ldbl-96/e_j1l.c (__ieee754_j1l): Likewise. (__ieee754_y1l): Likewise. (pone): Likewise. (qone): Likewise. * sysdeps/ieee754/ldbl-96/e_jnl.c (__ieee754_jnl): Likewise. (__ieee754_ynl): Likewise. * sysdeps/ieee754/ldbl-96/e_lgammal_r.c (sin_pi): Likewise. (__ieee754_lgammal_r): Likewise. * sysdeps/ieee754/ldbl-96/e_rem_pio2l.c (__ieee754_rem_pio2l): Likewise. * sysdeps/ieee754/ldbl-96/e_sinhl.c (__ieee754_sinhl): Likewise. * sysdeps/ieee754/ldbl-96/s_copysignl.c (__copysignl): Likewise. * sysdeps/ieee754/ldbl-96/s_erfl.c (__erfl): Likewise. (__erfcl): Likewise. * sysdeps/ieee754/ldbl-96/s_frexpl.c (__frexpl): Likewise. * sysdeps/ieee754/ldbl-96/s_issignalingl.c (__issignalingl): Likewise. * sysdeps/ieee754/ldbl-96/s_llrintl.c (__llrintl): Likewise. * sysdeps/ieee754/ldbl-96/s_llroundl.c (__llroundl): Likewise. * sysdeps/ieee754/ldbl-96/s_lrintl.c (__lrintl): Likewise. * sysdeps/ieee754/ldbl-96/s_lroundl.c (__lroundl): Likewise. * sysdeps/ieee754/ldbl-96/s_modfl.c (__modfl): Likewise. * sysdeps/ieee754/ldbl-96/s_nexttoward.c (__nexttoward): Likewise. * sysdeps/ieee754/ldbl-96/s_nexttowardf.c (__nexttowardf): Likewise. * sysdeps/ieee754/ldbl-96/s_nextupl.c (__nextupl): Likewise. * sysdeps/ieee754/ldbl-96/s_remquol.c (__remquol): Likewise. * sysdeps/ieee754/ldbl-96/s_roundl.c (__roundl): Likewise. * sysdeps/ieee754/ldbl-96/s_tanhl.c (__tanhl): Likewise. * sysdeps/ieee754/ldbl-opt/s_nexttowardfd.c (__nldbl_nexttowardf): Likewise. * sysdeps/m68k/m680x0/fpu/e_pow.c (s(__ieee754_pow)): Likewise. * sysdeps/m68k/m680x0/fpu/s_fpclassifyl.c (__fpclassifyl): Likewise. * sysdeps/m68k/m680x0/fpu/s_llrint.c (__llrint): Likewise. * sysdeps/m68k/m680x0/fpu/s_llrintf.c (__llrintf): Likewise. * sysdeps/m68k/m680x0/fpu/s_llrintl.c (__llrintl): Likewise. * sysdeps/m68k/m680x0/fpu/s_nextafterl.c (__nextafterl): Likewise. * sysdeps/x86/fpu/powl_helper.c (__powl_helper): Likewise.
* Optimized version of powf()Paul Clarke2017-06-231-101/+70
| | | | | | | | | Most significant changes are code simplification and use of doubles for intermediate values. Also, some rearrangement to move early non-dependent code later, out of the faster paths. * sysdeps/ieee754/flt-32/e_powf.c: Optimized implementation utilizing rearranged code and doubles float types.
* Fix powf inaccuracy (bug 21112).Joseph Myers2017-02-071-2/+2
| | | | | | | | | | | | | | | | | | | | Bug 21112 reports a case where powf is substantially inaccurate. This results from a multiplication where cp_h*p_h is required to be exact, and p_h is masked to have only 12 leading nonzero bits in its mantissa, but the value of cp_h has the 13th bit nonzero, leading to inexact multiplication results in some cases that can result in large errors in the final result of powf. This patch fixes this by using a value of cp_h correctly rounded to nearest to 12 bits, with a corresponding updated value of cp_l. Tested for x86_64 and x86. [BZ #21112] * sysdeps/ieee754/flt-32/e_powf.c (cp_h): Use value with trailing 12 bits zero. (cp_l): Update for new value of cp_h. * math/auto-libm-test-in: Add another test of pow. * math/auto-libm-test-out-pow: Regenerated.
* Fix sysdeps/ieee754 pow handling of sNaN arguments (bug 20916).Joseph Myers2016-12-021-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | Various pow function implementations mishandle sNaN arguments in various ways. This includes returning sNaN instead of qNaN for sNaN arguments. For arguments (1, sNaN) and (sNaN, 0), TS 18661-1 semantics are also that the result should be qNaN, whereas with a qNaN argument there the result should be 1, but for the dbl-64 implementation of pow there are issues with sNaN arguments beyond not implementing the TS 18661-1 semantics in those special cases. This patch makes the implementations in sysdeps/ieee754 follow the TS 18661-1 semantics consistently. Because x86 / x86_64 implementations still need fixing, testcases are not included with this patch; they will be included with the fix for the x86 / x86_64 versions. Tested for x86_64, x86, mips64 and powerpc (with such testcases, which pass in the mips64 and powerpc cases). [BZ #20916] * sysdeps/ieee754/dbl-64/e_pow.c (__ieee754_pow): Do not return 1 for arguments (sNaN, 0) or (1, sNaN). Do arithmetic on NaN arguments to compute result. * sysdeps/ieee754/flt-32/e_powf.c (__ieee754_powf): Do not return 1 for arguments (sNaN, 0) or (1, sNaN). * sysdeps/ieee754/ldbl-128/e_powl.c (__ieee754_powl): Likewise. * sysdeps/ieee754/ldbl-128ibm/e_powl.c (__ieee754_powl): Likewise.
* Fix powf inaccuracy (bug 18956).Joseph Myers2015-09-261-1/+3
| | | | | | | | | | | | | | | | | | | | | | The flt-32 version of powf can be inaccurate because of bugs in the extra-precision calculation of (x-1)/(x+1) or (x-1.5)/(x+1.5) as part of calculating log(x) with extra precision: a constant used (as part of adding 1 or 1.5 through integer arithmetic) is incorrect, and then the code fails to mask a computed high part before using it in arithmetic that relies on s_h*t_h being exactly representable. This patch fixes these bugs. Tested for x86_64 and x86. x86_64 ulps for powf removed and regenerated to reflect reduced ulps from the increased accuracy for existing tests. [BZ #18956] * sysdeps/ieee754/flt-32/e_powf.c (__ieee754_powf): Add 0x00400000 not 0x0040000 for high bit of mantissa. Mask with 0xfffff000 when extracting high part. * math/auto-libm-test-in: Add another test of pow. * math/auto-libm-test-out: Regenerated. * sysdeps/x86_64/fpu/libm-test-ulps: Update.
* Fix pow missing underflows (bug 18825).Joseph Myers2015-09-251-1/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Similar to various other bugs in this area, pow functions can fail to raise the underflow exception when the result is tiny and inexact but one or more low bits of the intermediate result that is scaled down (or, in the i386 case, converted from a wider evaluation format) are zero. This patch forces the exception in a similar way to previous fixes, thereby concluding the fixes for known bugs with missing underflow exceptions currently filed in Bugzilla. Tested for x86_64, x86, mips64 and powerpc. [BZ #18825] * sysdeps/i386/fpu/i386-math-asm.h (FLT_NARROW_EVAL_UFLOW_NONNAN): New macro. (DBL_NARROW_EVAL_UFLOW_NONNAN): Likewise. (LDBL_CHECK_FORCE_UFLOW_NONNAN): Likewise. * sysdeps/i386/fpu/e_pow.S: Use DEFINE_DBL_MIN. (__ieee754_pow): Use DBL_NARROW_EVAL_UFLOW_NONNAN instead of DBL_NARROW_EVAL, reloading the PIC register as needed. * sysdeps/i386/fpu/e_powf.S: Use DEFINE_FLT_MIN. (__ieee754_powf): Use FLT_NARROW_EVAL_UFLOW_NONNAN instead of FLT_NARROW_EVAL. Use separate return path for case when first argument is NaN. * sysdeps/i386/fpu/e_powl.S: Include <i386-math-asm.h>. Use DEFINE_LDBL_MIN. (__ieee754_powl): Use LDBL_CHECK_FORCE_UFLOW_NONNAN, reloading the PIC register. * sysdeps/ieee754/dbl-64/e_pow.c (__ieee754_pow): Use math_check_force_underflow_nonneg. * sysdeps/ieee754/flt-32/e_powf.c (__ieee754_powf): Force underflow for subnormal result. * sysdeps/ieee754/ldbl-128/e_powl.c (__ieee754_powl): Likewise. * sysdeps/ieee754/ldbl-128ibm/e_powl.c (__ieee754_powl): Use math_check_force_underflow_nonneg. * sysdeps/x86/fpu/powl_helper.c (__powl_helper): Use math_check_force_underflow. * sysdeps/x86_64/fpu/x86_64-math-asm.h (LDBL_CHECK_FORCE_UFLOW_NONNAN): New macro. * sysdeps/x86_64/fpu/e_powl.S: Include <x86_64-math-asm.h>. Use DEFINE_LDBL_MIN. (__ieee754_powl): Use LDBL_CHECK_FORCE_UFLOW_NONNAN. * math/auto-libm-test-in: Add more tests of pow. * math/auto-libm-test-out: Regenerated.
* Fix powf (close to -1, large) (bug 18647).Joseph Myers2015-08-051-1/+1
| | | | | | | | | | | | | | | | The flt-32 implementation of powf wrongly uses x-1 instead of |x|-1 when computing log (x) for the case where |x| is close to 1 and y is large. This patch fixes the logic accordingly. Relevant tests existed for x close to 1, and corresponding tests are added for x close to -1, as well as for some new variant cases. Tested for x86_64 and x86. [BZ #18647] * sysdeps/ieee754/flt-32/e_powf.c (__ieee754_powf): For large y and |x| close to 1, use absolute value of x when computing log. * math/auto-libm-test-in: Add more tests of pow. * math/auto-libm-test-out: Regenerated.
* Fix spurious underflows from pow with results close to 1 (bug 14811).Joseph Myers2012-11-071-0/+4
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* Use <> for math.h and math_private.h everywhere.Richard Henderson2012-03-091-2/+2
| | | | Entire tree edited via find | grep | sed.
* Optimize libmUlrich Drepper2011-10-121-28/+18
| | | | | libm is now somewhat integrated with gcc's -ffinite-math-only option and lots of the wrapper functions have been optimized.
* Update.Ulrich Drepper2001-02-191-0/+4
| | | | | * sysdeps/ieee754/flt-32/e_powf.c: Handle x == +-1 correctly. * sysdeps/ieee754/dbl-64/e_pow.c: Likewise.
* Update.Ulrich Drepper1999-07-141-0/+253