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* Update copyright dates with scripts/update-copyrightsJoseph Myers2023-01-06491-491/+491
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* Fix ldbl-128 built-in function useJoseph Myers2023-01-053-2/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | Fix the following issues with built-in function use in sysdeps/ieee754/ldbl-128 and sysdeps/ieee754/float128: * fabsl used __builtin_fabsf128 unconditionally, breaking the build with GCC 6 for several architectures; it should use __builtin_fabsl with an appropriate redirection in float128_private.h. (I'm not particularly concerned with building glibc with GCC 6; rather, I want to be able to run the tgmath.h tests with GCC 6, which is a significantly different case for tgmath.h compared to GCC 7 and later because of the lack of _FloatN / _FloatNx support in the compiler, and at present running the tests with a compiler means building glibc with that compiler.) * Some (conditional) uses of built-in functions had been added to ldbl-128 without appropriate float128_private.h remapping (there was remapping for the macros controlling whether the built-in functions are used, just not for the functions themselves). * s_llrintl.c called __builtin_round not __builtin_llrintl, which is obviously wrong. Tested with build-many-glibcs.py for aarch64-linux-gnu, GCC 6 (where it fixes the glibc build) and GCC 12, and with the glibc testsuite for x86_64.
* stdio-common: Convert vfprintf and related functions to buffersFlorian Weimer2022-12-193-76/+18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | vfprintf is entangled with vfwprintf (of course), __printf_fp, __printf_fphex, __vstrfmon_l_internal, and the strfrom family of functions. The latter use the internal snprintf functionality, so vsnprintf is converted as well. The simples conversion is __printf_fphex, followed by __vstrfmon_l_internal and __printf_fp, and finally __vfprintf_internal and __vfwprintf_internal. __vsnprintf_internal and strfrom* are mostly consuming the new interfaces, so they are comparatively simple. __printf_fp is a public symbol, so the FILE *-based interface had to preserved. The __printf_fp rewrite does not change the actual binary-to-decimal conversion algorithm, and digits are still not emitted directly to the target buffer. However, the staging buffer now uses bytes instead of wide characters, and one buffer copy is eliminated. The changes are at least performance-neutral in my testing. Floating point printing and snprintf improved measurably, so that this Lua script for i=1,5000000 do print(i, i * math.pi) end runs about 5% faster for me. To preserve fprintf performance for a simple "%d" format, this commit has some logic changes under LABEL (unsigned_number) to avoid additional function calls. There are certainly some very easy performance improvements here: binary, octal and hexadecimal formatting can easily avoid the temporary work buffer (the number of digits can be computed ahead-of-time using one of the __builtin_clz* built-ins). Decimal formatting can use a specialized version of _itoa_word for base 10. The existing (inconsistent) width handling between strfmon and printf is preserved here. __print_fp_buffer_1 would have to use __translated_number_width to achieve ISO conformance for printf. Test expectations in libio/tst-vtables-common.c are adjusted because the internal staging buffer merges all virtual function calls into one. In general, stack buffer usage is greatly reduced, particularly for unbuffered input streams. __printf_fp can still use a large buffer in binary128 mode for %g, though. Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
* Use GCC builtins for logb functions if desired.Xiaolin Tang2022-11-294-0/+18
| | | | | | | | This patch is using the corresponding GCC builtin for logbf, logb, logbl and logbf128 if the USE_FUNCTION_BUILTIN macros are defined to one in math-use-builtins-function.h. Co-Authored-By: Xi Ruoyao <xry111@xry111.site>
* Use GCC builtins for llrint functions if desired.Xiaolin Tang2022-11-294-17/+38
| | | | | | | | This patch is using the corresponding GCC builtin for llrintf, llrint, llrintl and llrintf128 if the USE_FUNCTION_BUILTIN macros are defined to one in math-use-builtins-function.h. Co-Authored-By: Xi Ruoyao <xry111@xry111.site>
* Use GCC builtins for lrint functions if desired.Xiaolin Tang2022-11-294-17/+38
| | | | | | | | This patch is using the corresponding GCC builtin for lrintf, lrint, lrintl and lrintf128 if the USE_FUNCTION_BUILTIN macros are defined to one in math-use-builtins-function.h. Co-Authored-By: Xi Ruoyao <xry111@xry111.site>
* Fix build with GCC 13 _FloatN, _FloatNx built-in functionsJoseph Myers2022-10-313-0/+380
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | GCC 13 has added more _FloatN and _FloatNx versions of existing <math.h> and <complex.h> built-in functions, for use in libstdc++-v3. This breaks the glibc build because of how those functions are defined as aliases to functions with the same ABI but different types. Add appropriate -fno-builtin-* options for compiling relevant files, as already done for the case of long double functions aliasing double ones and based on the list of files used there. I fixed some mistakes in that list of double files that I noticed while implementing this fix, but there may well be more such (harmless) cases, in this list or the new one (files that don't actually exist or don't define the named functions as aliases so don't need the options). I did try to exclude cases where glibc doesn't define certain functions for _FloatN or _FloatNx types at all from the new uses of -fno-builtin-* options. As with the options for double files (see the commit message for commit 49348beafe9ba150c9bd48595b3f372299bddbb0, "Fix build with GCC 10 when long double = double."), it's deliberate that the options are used even if GCC currently doesn't have a built-in version of a given functions, so providing some level of future-proofing against more such built-in functions being added in future. Tested with build-many-glibcs.py for aarch64-linux-gnu powerpc-linux-gnu powerpc64le-linux-gnu x86_64-linux-gnu (compilers and glibcs builds) with GCC mainline.
* Avoid undefined behaviour in ibm128 implementation of llroundl (BZ #29488)Aurelien Jarno2022-10-241-12/+9
| | | | | | | | Detecting an overflow edge case depended on signed overflow of a long long. Replace the additions and the overflow checks by __builtin_add_overflow(). Reviewed-by: Tulio Magno Quites Machado Filho <tuliom@linux.ibm.com>
* Fix BZ #29463 in the ibm128 implementation of y1l tooMichael Hudson-Doyle2022-10-241-0/+3
| | | | | | | | | Avoid moving code across SET_RESTORE_ROUNDL in order to fix [BZ #29463]. Tested-by: Aurelien Jarno <aurelien@aurel32.net> Reviewed-by: Aurelien Jarno <aurelien@aurel32.net> Reviewed-by: Tulio Magno Quites Machado Filho <tuliom@linux.ibm.com>
* math: Fix asin and acos invalid exception with old gccSzabolcs Nagy2022-10-171-16/+2
| | | | | | | | | | | | | | This works around a gcc issue where it const folded inf/inf into nan, preventing the invalid exception to be signalled. (x-x)/(x-x) is more robust against optimizations and works for all out of bounds values including x==nan. The gcc issue https://gcc.gnu.org/bugzilla/show_bug.cgi?id=95115 should be fixed on release branches starting from gcc-10, but it is better to change the code in case glibc is built with older gcc. Reviewed-by: Wilco Dijkstra <Wilco.Dijkstra@arm.com>
* Update _FloatN header support for C++ in GCC 13Joseph Myers2022-09-281-3/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | GCC 13 adds support for _FloatN and _FloatNx types in C++, so breaking the installed glibc headers that assume such support is not present. GCC mostly works around this with fixincludes, but that doesn't help for building glibc and its tests (glibc doesn't itself contain C++ code, but there's C++ code built for tests). Update glibc's bits/floatn-common.h and bits/floatn.h headers to handle the GCC 13 support directly. In general the changes match those made by fixincludes, though I think the ones in sysdeps/powerpc/bits/floatn.h, where the header tests __LDBL_MANT_DIG__ == 113 or uses #elif, wouldn't match the existing fixincludes patterns. Some places involving special C++ handling in relation to _FloatN support are not changed. There's no need to change the __HAVE_FLOATN_NOT_TYPEDEF definition (also in a form that wouldn't be matched by the fixincludes fixes) because it's only used in relation to macro definitions using features not supported for C++ (__builtin_types_compatible_p and _Generic). And there's no need to change the inline function overloads for issignaling, iszero and iscanonical in C++ because cases where types have the same format but are no longer compatible types are handled automatically by the C++ overload resolution rules. This patch also does not change the overload handling for iseqsig, and there I think changes *are* needed, beyond those in this patch or made by fixincludes. The way that overload is defined, via a template parameter to a structure type, requires overloads whenever the types are incompatible, even if they have the same format. So I think we need to add overloads with GCC 13 for every supported _FloatN and _FloatNx type, rather than just having one for _Float128 when it has a different ABI to long double as at present (but for older GCC, such overloads must not be defined for types that end up defined as typedefs for another type). Tested with build-many-glibcs.py: compilers build for aarch64-linux-gnu ia64-linux-gnu mips64-linux-gnu powerpc-linux-gnu powerpc64le-linux-gnu x86_64-linux-gnu; glibcs build for aarch64-linux-gnu ia64-linux-gnu i686-linux-gnu mips-linux-gnu mips64-linux-gnu-n32 powerpc-linux-gnu powerpc64le-linux-gnu x86_64-linux-gnu.
* Ensure calculations happen with desired rounding mode in y1lf128Michael Hudson-Doyle2022-08-181-0/+3
| | | | | | | | | | | | math/test-float128-y1 fails on x86_64 and ppc64el with gcc 12 and -O3, because code inside a block guarded by SET_RESTORE_ROUNDL is being moved after the rounding mode has been restored. Use math_force_eval to prevent this (and insert some math_opt_barrier calls to prevent code from being moved before the rounding mode is set). Fixes #29463 Reviewed-By: Wilco Dijkstra <Wilco.Dijkstra@arm.com>
* i686: Use generic sincosf implementation for SSE2 versionAdhemerval Zanella2022-06-011-0/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The generic implementation shows slight better performance (gcc 11.2.1 on a Ryzen 9 5900X): * s_sincosf-sse2.S: "sincosf": { "workload-random": { "duration": 3.89961e+09, "iterations": 9.5472e+07, "reciprocal-throughput": 40.8429, "latency": 40.8483, "max-throughput": 2.4484e+07, "min-throughput": 2.44808e+07 } } * generic s_cossinf.c: "sincosf": { "workload-random": { "duration": 3.71953e+09, "iterations": 1.48512e+08, "reciprocal-throughput": 25.0515, "latency": 25.0391, "max-throughput": 3.99177e+07, "min-throughput": 3.99375e+07 } } Checked on i686-linux-gnu. Reviewed-by: H.J. Lu <hjl.tools@gmail.com>
* i686: Use generic sinf implementation for SSE2 versionAdhemerval Zanella2022-06-011-0/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Performance seems to be similar (gcc 11.2.1 on a Ryzen 9 5900X), the generic algorithm shows slight better performance for the 'workload-huge.wrf' input set. * s_sinf-sse2.S: "sinf": { "": { "duration": 3.72405e+09, "iterations": 2.38374e+08, "max": 63.973, "min": 11.211, "mean": 15.6227 }, "workload-random.wrf": { "duration": 3.76923e+09, "iterations": 8.4e+07, "reciprocal-throughput": 17.6355, "latency": 72.108, "max-throughput": 5.67037e+07, "min-throughput": 1.38681e+07 }, "workload-huge.wrf": { "duration": 3.76943e+09, "iterations": 6e+07, "reciprocal-throughput": 29.3493, "latency": 96.2985, "max-throughput": 3.40724e+07, "min-throughput": 1.03844e+07 } } * generic s_sinf.c: "sinf": { "": { "duration": 3.70989e+09, "iterations": 2.18025e+08, "max": 69.782, "min": 11.1, "mean": 17.0159 }, "workload-random.wrf": { "duration": 3.77213e+09, "iterations": 9.6e+07, "reciprocal-throughput": 17.5402, "latency": 61.0459, "max-throughput": 5.70119e+07, "min-throughput": 1.63811e+07 }, "workload-huge.wrf": { "duration": 3.81576e+09, "iterations": 5.6e+07, "reciprocal-throughput": 38.2111, "latency": 98.0659, "max-throughput": 2.61704e+07, "min-throughput": 1.01972e+07 } } Checked on i686-linux-gnu. Reviewed-by: H.J. Lu <hjl.tools@gmail.com>
* i686: Use generic cosf implementation for SSE2 versionAdhemerval Zanella2022-06-011-0/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Performance seems to be similar (gcc 11.2.1 on a Ryzen 9 5900X): * s_cosf-sse2.S: "cosf": { "workload-random": { "duration": 3.74987e+09, "iterations": 9.616e+07, "reciprocal-throughput": 15.8141, "latency": 62.1782, "max-throughput": 6.32346e+07, "min-throughput": 1.60828e+07 } } * generic s_cosf.c: "cosf": { "workload-random": { "duration": 3.87298e+09, "iterations": 1.00968e+08, "reciprocal-throughput": 18.3448, "latency": 58.3722, "max-throughput": 5.45113e+07, "min-throughput": 1.71314e+07 } } Checked on i686-linux-gnu.
* x86_64: Optimize sincos where sin/cos is optimized (bug 29193)Andreas Schwab2022-06-011-0/+7
| | | | | | | The compiler may substitute calls to sin or cos with calls to sincos, thus we should have the same optimized implementations for sincos. The optimized implementations may produce results that differ, that also makes sure that the sincos call aggrees with the sin and cos calls.
* math: Add math-use-builtins-fabs (BZ#29027)Adhemerval Zanella2022-05-233-5/+36
| | | | | | | | | | | | | | | | | | Both float, double, and _Float128 are assumed to be supported (float and double already only uses builtins). Only long double is parametrized due GCC bug 29253 which prevents its usage on powerpc. It allows to remove i686, ia64, x86_64, powerpc, and sparc arch specific implementation. On ia64 it also fixes the sNAN handling: math/test-float64x-fabs math/test-ldouble-fabs Checked on x86_64-linux-gnu, i686-linux-gnu, powerpc-linux-gnu, powerpc64-linux-gnu, sparc64-linux-gnu, and ia64-linux-gnu.
* math: Use builtin for ldbl-96 copysignAdhemerval Zanella2022-04-071-7/+3
| | | | | | | All architectures that uses it (x86, ia64, m68k) implement the builtin. Checked on x86_64-linux-gnu and ia64-linux-gnu.
* math: Fix float conversion regressions with gcc-12 [BZ #28713]Szabolcs Nagy2022-01-106-16/+16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Converting double precision constants to float is now affected by the runtime dynamic rounding mode instead of being evaluated at compile time with default rounding mode (except static object initializers). This can change the computed result and cause performance regression. The known correctness issues (increased ulp errors) are already fixed, this patch fixes remaining cases of unnecessary runtime conversions. Add float M_* macros to math.h as new GNU extension API. To avoid conversions the new M_* macros are used and instead of casting double literals to float, use float literals (only required if the conversion is inexact). The patch was tested on aarch64 where the following symbols had new spurious conversion instructions that got fixed: __clog10f __gammaf_r_finite@GLIBC_2.17 __j0f_finite@GLIBC_2.17 __j1f_finite@GLIBC_2.17 __jnf_finite@GLIBC_2.17 __kernel_casinhf __lgamma_negf __log1pf __y0f_finite@GLIBC_2.17 __y1f_finite@GLIBC_2.17 cacosf cacoshf casinhf catanf catanhf clogf gammaf_positive Fixes bug 28713. Reviewed-by: Paul Zimmermann <Paul.Zimmermann@inria.fr>
* Update copyright dates with scripts/update-copyrightsPaul Eggert2022-01-01490-490/+490
| | | | | | | | | | | | | | | | | | | | | | | I used these shell commands: ../glibc/scripts/update-copyrights $PWD/../gnulib/build-aux/update-copyright (cd ../glibc && git commit -am"[this commit message]") and then ignored the output, which consisted lines saying "FOO: warning: copyright statement not found" for each of 7061 files FOO. I then removed trailing white space from math/tgmath.h, support/tst-support-open-dev-null-range.c, and sysdeps/x86_64/multiarch/strlen-vec.S, to work around the following obscure pre-commit check failure diagnostics from Savannah. I don't know why I run into these diagnostics whereas others evidently do not. remote: *** 912-#endif remote: *** 913: remote: *** 914- remote: *** error: lines with trailing whitespace found ... remote: *** error: sysdeps/unix/sysv/linux/statx_cp.c: trailing lines
* s_sincosf.h: Change pio4 type to float [BZ #28713]H.J. Lu2021-12-211-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | s_cosf.c and s_sinf.c have if (abstop12 (y) < abstop12 (pio4)) where abstop12 takes a float argument, but pio4 is static const double. pio4 is used only in calls to abstop12 and never in arithmetic. Apply -static const double pio4 = 0x1.921FB54442D18p-1; +static const float pio4 = 0x1.921FB6p-1f; to fix: FAIL: math/test-float-cos FAIL: math/test-float-sin FAIL: math/test-float-sincos FAIL: math/test-float32-cos FAIL: math/test-float32-sin FAIL: math/test-float32-sincos when compiling with GCC 12. Reviewed-by: Paul Zimmermann <Paul.Zimmermann@inria.fr>
* sysdeps: Simplify sin Taylor Series calculationAkila Welihinda2021-12-131-5/+5
| | | | | | | | | | | | The macro TAYLOR_SIN adds the term `-0.5*da*a^2 + da` in hopes of regaining some precision as a function of da. However the comment says we add the term `-0.5*da*a^2 + 0.5*da` which is different. This fix updates the comment to reflect the code and also simplifies the calculation by replacing `a` with `x` because they always have the same value. Signed-off-by: Akila Welihinda <akilawelihinda@ucla.edu> Reviewed-by: Paul Zimmermann <Paul.Zimmermann@inria.fr>
* math: Remove the error handling wrapper from hypot and hypotfAdhemerval Zanella2021-12-134-9/+39
| | | | | | | | | | | | The error handling is moved to sysdeps/ieee754 version with no SVID support. The compatibility symbol versions still use the wrapper with SVID error handling around the new code. There is no new symbol version nor compatibility code on !LIBM_SVID_COMPAT targets (e.g. riscv). Only ia64 is unchanged, since it still uses the arch specific __libm_error_region on its implementation. Checked on x86_64-linux-gnu, i686-linux-gnu, and aarch64-linux-gnu.
* math: Use fmin/fmax on hypotWilco Dijkstra2021-12-131-2/+3
| | | | | | It optimizes for architectures that provides fast builtins. Checked on aarch64-linux-gnu.
* math: Use an improved algorithm for hypotl (ldbl-128)Adhemerval Zanella2021-12-131-130/+96
| | | | | | | | | | | | | | | | | | | | | This implementation is based on 'An Improved Algorithm for hypot(a,b)' by Carlos F. Borges [1] using the MyHypot3 with the following changes: - Handle qNaN and sNaN. - Tune the 'widely varying operands' to avoid spurious underflow due the multiplication and fix the return value for upwards rounding mode. - Handle required underflow exception for subnormal results. The main advantage of the new algorithm is its precision. With a random 1e9 input pairs in the range of [LDBL_MIN, LDBL_MAX], glibc current implementation shows around 0.05% results with an error of 1 ulp (453266 results) while the new implementation only shows 0.0001% of total (1280). Checked on aarch64-linux-gnu and x86_64-linux-gnu. [1] https://arxiv.org/pdf/1904.09481.pdf
* math: Use an improved algorithm for hypotl (ldbl-96)Adhemerval Zanella2021-12-131-133/+98
| | | | | | | | | | | | | | | | | | | This implementation is based on 'An Improved Algorithm for hypot(a,b)' by Carlos F. Borges [1] using the MyHypot3 with the following changes: - Handle qNaN and sNaN. - Tune the 'widely varying operands' to avoid spurious underflow due the multiplication and fix the return value for upwards rounding mode. - Handle required underflow exception for subnormal results. The main advantage of the new algorithm is its precision. With a random 1e8 input pairs in the range of [LDBL_MIN, LDBL_MAX], glibc current implementation shows around 0.02% results with an error of 1 ulp (23158 results) while the new implementation only shows 0.0001% of total (111). [1] https://arxiv.org/pdf/1904.09481.pdf
* math: Improve hypot performance with FMAWilco Dijkstra2021-12-131-1/+16
| | | | | | | | | | | Improve hypot performance significantly by using fma when available. The fma version has twice the throughput of the previous version and 70% of the latency. The non-fma version has 30% higher throughput and 10% higher latency. Max ULP error is 0.949 with fma and 0.792 without fma. Passes GLIBC testsuite.
* math: Use an improved algorithm for hypot (dbl-64)Wilco Dijkstra2021-12-131-143/+92
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This implementation is based on the 'An Improved Algorithm for hypot(a,b)' by Carlos F. Borges [1] using the MyHypot3 with the following changes: - Handle qNaN and sNaN. - Tune the 'widely varying operands' to avoid spurious underflow due the multiplication and fix the return value for upwards rounding mode. - Handle required underflow exception for denormal results. The main advantage of the new algorithm is its precision: with a random 1e9 input pairs in the range of [DBL_MIN, DBL_MAX], glibc current implementation shows around 0.34% results with an error of 1 ulp (3424869 results) while the new implementation only shows 0.002% of total (18851). The performance result are also only slight worse than current implementation. On x86_64 (Ryzen 5900X) with gcc 12: Before: "hypot": { "workload-random": { "duration": 3.73319e+09, "iterations": 1.12e+08, "reciprocal-throughput": 22.8737, "latency": 43.7904, "max-throughput": 4.37184e+07, "min-throughput": 2.28361e+07 } } After: "hypot": { "workload-random": { "duration": 3.7597e+09, "iterations": 9.8e+07, "reciprocal-throughput": 23.7547, "latency": 52.9739, "max-throughput": 4.2097e+07, "min-throughput": 1.88772e+07 } } Co-Authored-By: Adhemerval Zanella <adhemerval.zanella@linaro.org> Checked on x86_64-linux-gnu and aarch64-linux-gnu. [1] https://arxiv.org/pdf/1904.09481.pdf
* math: Simplify hypotf implementationAdhemerval Zanella2021-12-132-35/+37
| | | | | | | | | | | | Use a more optimized comparison for check for NaN and infinite and add an inlined issignaling implementation for float. With gcc it results in 2 FP comparisons. The file Copyright is also changed to use GPL, the implementation was completely changed by 7c10fd3515f to use double precision instead of scaling and this change removes all the GET_FLOAT_WORD usage. Checked on x86_64-linux-gnu.
* Fixed inaccuracy of j0f (BZ #28185)Paul Zimmermann2021-10-051-3/+3
| | | | | | | | | | | | | The largest errors over the full binary32 range are after this patch (on x86_64): RNDN: libm wrong by up to 9.00e+00 ulp(s) [9] for x=0x1.04c39cp+6 RNDZ: libm wrong by up to 9.00e+00 ulp(s) [9] for x=0x1.04c39cp+6 RNDU: libm wrong by up to 9.00e+00 ulp(s) [9] for x=0x1.04c39cp+6 RNDD: libm wrong by up to 8.98e+00 ulp(s) [9] for x=0x1.4b7066p+7 Inputs that were yielding huge errors have been added to "make check". Reviewed-by: Adhemeral Zanella <adhemerval.zanella@linaro.org>
* Add fmaximum, fminimum functionsJoseph Myers2021-09-2810-1/+227
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | C2X adds new <math.h> functions for floating-point maximum and minimum, corresponding to the new operations that were added in IEEE 754-2019 because of concerns about the old operations not being associative in the presence of signaling NaNs. fmaximum and fminimum handle NaNs like most <math.h> functions (any NaN argument means the result is a quiet NaN). fmaximum_num and fminimum_num handle both quiet and signaling NaNs the way fmax and fmin handle quiet NaNs (if one argument is a number and the other is a NaN, return the number), but still raise "invalid" for a signaling NaN argument, making them exceptions to the normal rule that a function with a floating-point result raising "invalid" also returns a quiet NaN. fmaximum_mag, fminimum_mag, fmaximum_mag_num and fminimum_mag_num are corresponding functions returning the argument with greatest or least absolute value. All these functions also treat +0 as greater than -0. There are also corresponding <tgmath.h> type-generic macros. Add these functions to glibc. The implementations use type-generic templates based on those for fmax, fmin, fmaxmag and fminmag, and test inputs are based on those for those functions with appropriate adjustments to the expected results. The RISC-V maintainers might wish to add optimized versions of fmaximum_num and fminimum_num (for float and double), since RISC-V (F extension version 2.2 and later) provides instructions corresponding to those functions - though it might be at least as useful to add architecture-independent built-in functions to GCC and teach the RISC-V back end to expand those functions inline, which is what you generally want for functions that can be implemented with a single instruction. Tested for x86_64 and x86, and with build-many-glibcs.py.
* powerpc64le: Avoid conflicting types for f64xfmaf128 when IFUNC is not usedTulio Magno Quites Machado Filho2021-09-231-0/+2
| | | | | | | | | Avoid defining f64xfmaf128 twice when building s_fmaf128.c. This can be reproduced on powerpc64le whenever f128 functions do not have IFUNC enabled, e.g. using "--with-cpu=power8 --disable-multi-arch", or when using "-with-cpu=power9". Fixes: b3f27d8150d4f ("Add narrowing fma functions")
* Add narrowing fma functionsJoseph Myers2021-09-2226-1/+598
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch adds the narrowing fused multiply-add functions from TS 18661-1 / TS 18661-3 / C2X to glibc's libm: ffma, ffmal, dfmal, f32fmaf64, f32fmaf32x, f32xfmaf64 for all configurations; f32fmaf64x, f32fmaf128, f64fmaf64x, f64fmaf128, f32xfmaf64x, f32xfmaf128, f64xfmaf128 for configurations with _Float64x and _Float128; __f32fmaieee128 and __f64fmaieee128 aliases in the powerpc64le case (for calls to ffmal and dfmal when long double is IEEE binary128). Corresponding tgmath.h macro support is also added. The changes are mostly similar to those for the other narrowing functions previously added, especially that for sqrt, so the description of those generally applies to this patch as well. As with sqrt, I reused the same test inputs in auto-libm-test-in as for non-narrowing fma rather than adding extra or separate inputs for narrowing fma. The tests in libm-test-narrow-fma.inc also follow those for non-narrowing fma. The non-narrowing fma has a known bug (bug 6801) that it does not set errno on errors (overflow, underflow, Inf * 0, Inf - Inf). Rather than fixing this or having narrowing fma check for errors when non-narrowing does not (complicating the cases when narrowing fma can otherwise be an alias for a non-narrowing function), this patch does not attempt to check for errors from narrowing fma and set errno; the CHECK_NARROW_FMA macro is still present, but as a placeholder that does nothing, and this missing errno setting is considered to be covered by the existing bug rather than needing a separate open bug. missing-errno annotations are duly added to many of the auto-libm-test-in test inputs for fma. This completes adding all the new functions from TS 18661-1 to glibc, so will be followed by corresponding stdc-predef.h changes to define __STDC_IEC_60559_BFP__ and __STDC_IEC_60559_COMPLEX__, as the support for TS 18661-1 will be at a similar level to that for C standard floating-point facilities up to C11 (pragmas not implemented, but library functions done). (There are still further changes to be done to implement changes to the types of fromfp functions from N2548.) Tested as followed: natively with the full glibc testsuite for x86_64 (GCC 11, 7, 6) and x86 (GCC 11); with build-many-glibcs.py with GCC 11, 7 and 6; cross testing of math/ tests for powerpc64le, powerpc32 hard float, mips64 (all three ABIs, both hard and soft float). The different GCC versions are to cover the different cases in tgmath.h and tgmath.h tests properly (GCC 6 has _Float* only as typedefs in glibc headers, GCC 7 has proper _Float* support, GCC 8 adds __builtin_tgmath).
* Fix f64xdivf128, f64xmulf128 spurious underflows (bug 28358)Joseph Myers2021-09-2112-12/+16
| | | | | | | | | | | | | | | | | | | | | | | | | | As described in bug 28358, the round-to-odd computations used in the libm functions that round their results to a narrower format can yield spurious underflow exceptions in the following circumstances: the narrowing only narrows the precision of the type and not the exponent range (i.e., it's narrowing _Float128 to _Float64x on x86_64, x86 or ia64), the architecture does after-rounding tininess detection (which applies to all those architectures), the result is inexact, tiny before rounding but not tiny after rounding (with the chosen rounding mode) for _Float64x (which is possible for narrowing mul, div and fma, not for narrowing add, sub or sqrt), so the underflow exception resulting from the toward-zero computation in _Float128 is spurious for _Float64x. Fixed by making ROUND_TO_ODD call feclearexcept (FE_UNDERFLOW) in the problem cases (as indicated by an extra argument to the macro); there is never any need to preserve underflow exceptions from this part of the computation, because the conversion of the round-to-odd value to the narrower type will underflow in exactly the cases in which the function should raise that exception, but it may be more efficient to avoid the extra manipulation of the floating-point environment when not needed. Tested for x86_64 and x86, and with build-many-glibcs.py.
* Redirect fma calls to __fma in libmJoseph Myers2021-09-1511-0/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | include/math.h has a mechanism to redirect internal calls to various libm functions, that can often be inlined by the compiler, to call non-exported __* names for those functions in the case when the calls aren't inlined, with the redirection being disabled when NO_MATH_REDIRECT. Add fma to the functions to which this mechanism is applied. At present, libm-internal fma calls (generally to __builtin_fma* functions) are only done when it's known the call will be inlined, with alternative code not relying on an fma operation being used in the caller otherwise. This patch is in preparation for adding the TS 18661 / C2X narrowing fma functions to glibc; it will be natural for the narrowing function implementations to call the underlying fma functions unconditionally, with this either being inlined or resulting in an __fma* call. (Using two levels of round-to-odd computation like that, in the case where there isn't an fma hardware instruction, isn't optimal but is certainly a lot simpler for the initial implementation than writing different narrowing fma implementations for all the various pairs of formats.) Tested with build-many-glibcs.py that installed stripped shared libraries are unchanged by the patch (using <https://sourceware.org/pipermail/libc-alpha/2021-September/130991.html> to fix installed library stripping in build-many-glibcs.py). Also tested for x86_64.
* Add narrowing square root functionsJoseph Myers2021-09-1020-1/+523
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch adds the narrowing square root functions from TS 18661-1 / TS 18661-3 / C2X to glibc's libm: fsqrt, fsqrtl, dsqrtl, f32sqrtf64, f32sqrtf32x, f32xsqrtf64 for all configurations; f32sqrtf64x, f32sqrtf128, f64sqrtf64x, f64sqrtf128, f32xsqrtf64x, f32xsqrtf128, f64xsqrtf128 for configurations with _Float64x and _Float128; __f32sqrtieee128 and __f64sqrtieee128 aliases in the powerpc64le case (for calls to fsqrtl and dsqrtl when long double is IEEE binary128). Corresponding tgmath.h macro support is also added. The changes are mostly similar to those for the other narrowing functions previously added, so the description of those generally applies to this patch as well. However, the not-actually-narrowing cases (where the two types involved in the function have the same floating-point format) are aliased to sqrt, sqrtl or sqrtf128 rather than needing a separately built not-actually-narrowing function such as was needed for add / sub / mul / div. Thus, there is no __nldbl_dsqrtl name for ldbl-opt because no such name was needed (whereas the other functions needed such a name since the only other name for that entry point was e.g. f32xaddf64, not reserved by TS 18661-1); the headers are made to arrange for sqrt to be called in that case instead. The DIAG_* calls in sysdeps/ieee754/soft-fp/s_dsqrtl.c are because they were observed to be needed in GCC 7 testing of riscv32-linux-gnu-rv32imac-ilp32. The other sysdeps/ieee754/soft-fp/ files added didn't need such DIAG_* in any configuration I tested with build-many-glibcs.py, but if they do turn out to be needed in more files with some other configuration / GCC version, they can always be added there. I reused the same test inputs in auto-libm-test-in as for non-narrowing sqrt rather than adding extra or separate inputs for narrowing sqrt. The tests in libm-test-narrow-sqrt.inc also follow those for non-narrowing sqrt. Tested as followed: natively with the full glibc testsuite for x86_64 (GCC 11, 7, 6) and x86 (GCC 11); with build-many-glibcs.py with GCC 11, 7 and 6; cross testing of math/ tests for powerpc64le, powerpc32 hard float, mips64 (all three ABIs, both hard and soft float). The different GCC versions are to cover the different cases in tgmath.h and tgmath.h tests properly (GCC 6 has _Float* only as typedefs in glibc headers, GCC 7 has proper _Float* support, GCC 8 adds __builtin_tgmath).
* Remove "Contributed by" linesSiddhesh Poyarekar2021-09-03201-247/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | We stopped adding "Contributed by" or similar lines in sources in 2012 in favour of git logs and keeping the Contributors section of the glibc manual up to date. Removing these lines makes the license header a bit more consistent across files and also removes the possibility of error in attribution when license blocks or files are copied across since the contributed-by lines don't actually reflect reality in those cases. Move all "Contributed by" and similar lines (Written by, Test by, etc.) into a new file CONTRIBUTED-BY to retain record of these contributions. These contributors are also mentioned in manual/contrib.texi, so we just maintain this additional record as a courtesy to the earlier developers. The following scripts were used to filter a list of files to edit in place and to clean up the CONTRIBUTED-BY file respectively. These were not added to the glibc sources because they're not expected to be of any use in future given that this is a one time task: https://gist.github.com/siddhesh/b5ecac94eabfd72ed2916d6d8157e7dc https://gist.github.com/siddhesh/15ea1f5e435ace9774f485030695ee02 Reviewed-by: Carlos O'Donell <carlos@redhat.com>
* Update math: redirect roundeven functionH.J. Lu2021-06-271-0/+1
| | | | | Redirect target specific roundeven functions for aarch64, ldbl-128ibm and riscv.
* Use GCC builtins for roundeven functions if desired.Shen-Ta Hsieh2021-06-274-0/+17
| | | | | | | | | | | | | This patch is using the corresponding GCC builtin for roundevenf, roundeven and roundevenl if the USE_FUNCTION_BUILTIN macros are defined to one in math-use-builtins.h. These builtin functions is supported since GCC 10. The code of the generic implementation is not changed. Signed-off-by: Shen-Ta Hsieh <ibmibmibm.tw@gmail.com> Reviewed-by: H.J. Lu <hjl.tools@gmail.com>
* math: redirect roundeven functionShen-Ta Hsieh2021-06-275-1/+9
| | | | | | | This patch redirect roundeven function for futhermore changes. Signed-off-by: Shen-Ta Hsieh <ibmibmibm.tw@gmail.com> Reviewed-by: H.J. Lu <hjl.tools@gmail.com>
* configure: Replaced obsolete AC_TRY_COMPILENaohiro Tamura2021-06-041-4/+4
| | | | | | | | | | | | | | | | | This patch replaced obsolete AC_TRY_COMPILE to AC_COMPILE_IFELSE or AC_PREPROC_IFELSE. It has been confirmed that GNU 'autoconf' 2.69 suppressed obsolete warnings, updated the following files: - configure - sysdeps/mach/configure - sysdeps/mach/hurd/configure - sysdeps/s390/configure - sysdeps/unix/sysv/linux/configure and didn't change the following files: - sysdeps/ieee754/ldbl-opt/configure - sysdeps/unix/sysv/linux/powerpc/configure Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
* stdio-common: Remove _IO_vfwscanfFlorian Weimer2021-06-011-1/+0
| | | | | | | | | The symbol has never been exported, so no compatibility symbol is needed. Removing this file prevents ld from creation an exported symbol in case GLIBC_2_0 expands to a symbol version which does not have a local: *; directive in the symbol version map file. Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
* add workload traces for cbrtlPaul Zimmermann2021-05-101-0/+3
| | | | | | These workload traces cover the whole "long double" range. This patch was prepared with the help of Adhemerval Zanella. Reviewed-by: Carlos O'Donell <carlos@redhat.com>
* Improve the accuracy of tgamma (BZ #26983)Paul Zimmermann2021-04-071-11/+26
| | | | | | | | | | | | With this patch, the maximal known error for tgamma is now reduced to 9 ulps for dbl-64, for all rounding modes. Since exhaustive testing is not possible for dbl-64, it might be that there are still cases with an error larger than 9 ulps, but all known cases are fixed (intensive tests were done to find cases with large errors). Tested on x86_64 and powerpc (and by Adhemerval Zanella on aarch64, arm, s390x, sparc, and i686). Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
* Fix the inaccuracy of j0f/j1f/y0f/y1f [BZ #14469, #14470, #14471, #14472]Paul Zimmermann2021-04-023-70/+1021
| | | | | | | | | | | | | | | | | | | | | | | For j0f/j1f/y0f/y1f, the largest error for all binary32 inputs is reduced to at most 9 ulps for all rounding modes. The new code is enabled only when there is a cancellation at the very end of the j0f/j1f/y0f/y1f computation, or for very large inputs, thus should not give any visible slowdown on average. Two different algorithms are used: * around the first 64 zeros of j0/j1/y0/y1, approximation polynomials of degree 3 are used, computed using the Sollya tool (https://www.sollya.org/) * for large inputs, an asymptotic formula from [1] is used [1] Fast and Accurate Bessel Function Computation, John Harrison, Proceedings of Arith 19, 2009. Inputs yielding the new largest errors are added to auto-libm-test-in, and ulps are regenerated for various targets (thanks Adhemerval Zanella). Tested on x86_64 with --disable-multi-arch and on powerpc64le-linux-gnu. Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
* Move __isnanf128 to libc.soSiddhesh Poyarekar2021-03-303-1/+24
| | | | | | | | All of the isnan functions are in libc.so due to printf_fp, so move __isnanf128 there too for consistency. Reviewed-by: Tulio Magno Quites Machado Filho <tuliom@ascii.art.br> Reviewed-by: Florian Weimer <fweimer@redhat.com>
* math: Remove mpa files (part 2) [BZ #15267]Wilco Dijkstra2021-03-1115-2452/+0
| | | | | | | | | Previous commit was missing deleted files in sysdeps/ieee754/dbl-64. Finally remove all mpa related files, headers, declarations, probes, unused tables and update makefiles. Reviewed-By: Paul Zimmermann <Paul.Zimmermann@inria.fr>
* math: Remove mpa files [BZ #15267]Wilco Dijkstra2021-03-115-7823/+0
| | | | | | | Finally remove all mpa related files, headers, declarations, probes, unused tables and update makefiles. Reviewed-By: Paul Zimmermann <Paul.Zimmermann@inria.fr>
* math: Remove slow paths from atan2 [BZ #15267]Wilco Dijkstra2021-03-112-294/+40
| | | | | | Remove slow paths from atan2. Add ULP annotations. Reviewed-By: Paul Zimmermann <Paul.Zimmermann@inria.fr>
* math: Remove slow paths from atan [BZ #15267]Wilco Dijkstra2021-03-113-181/+27
| | | | | | Remove slow paths from atan. Add ULP annotations. Reviewed-By: Paul Zimmermann <Paul.Zimmermann@inria.fr>