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2019-04-17define FP_FAST_FMA* when fma* can be inlinedSzabolcs Nagy-0/+12
FP_FAST_FMA can be defined if "the fma function generally executes about as fast as, or faster than, a multiply and an add of double operands", which can only be true if the fma call is inlined as an instruction. gcc sets __FP_FAST_FMA if __builtin_fma is inlined as an instruction, but that does not mean an fma call will be inlined (e.g. it is defined with -fno-builtin-fma), other compilers (clang) don't even have such macro, but this is the closest we can get. (even if the libc fma implementation is a single instruction, the extern call overhead is already too big when the macro is used to decide between x*y+z and fma(x,y,z) so it cannot be based on libc only, defining the macro unconditionally on targets which have fma in the base isa is also incorrect: the compiler might not inline fma anyway.) this solution works with gcc unless fma inlining is explicitly turned off.
2018-08-22fix FP_ILOGB0 and FP_ILOGBNAN definitions to be valid for use in #ifRich Felker-1/+1
commit 98c9af500125df41fdb46d7e384b00982d72493a wrongly claimed they do not need to be valid for such usage, but the last sentence of C11 7.1.4 ΒΆ1 imposes a broad requirement that all macros specified as integer constant expressions also need to be valid for #if. simply write the value out explicitly. there is no value here in pretending that the width of int will vary.
2014-03-09math.h: make __FLOAT_BITS and __DOUBLE_BITS C89Szabolcs Nagy-2/+4
Remove non-constant aggregate initializer. (Still using long long, but that is supported by ancient compilers without __extension__ anyway).
2013-11-26adjust fallback INFINITY definition for FLT_EVAL_METHOD==2 caseRich Felker-1/+1
on archs with excess precision, the floating point constant 1e40f may be evaluated such that it does not actually produce an infinity. 1e5000f is sufficiently large to produce an infinity for all supported floating point formats. note that this definition of INFINITY is only used for old or non-GNUC compilers anyway; despite being a portable, conforming definition, it leads to erroneous warnings on many compilers and thus using the builtin is preferred.
2013-11-21math: add (obsolete) bsd drem and finite functionsSzabolcs Nagy-0/+6
2013-11-20write floating point limit constants to 21 significant decimal placesRich Felker-2/+2
this is enough to produce the correct value even if the constant is interpreted as 80-bit extended precision, which matters on archs with excess precision (FLT_EVAL_METHOD==2) under at least some interpretations of the C standard. the shorter representations, while correct if converted to the nominal precision at translation time, could produce an incorrect value at extended precision, yielding results such as (double)DBL_MAX != DBL_MAX.
2013-09-27math: fix comparision macros (isless etc) when FLT_EVAL_METHOD!=0Szabolcs Nagy-10/+10
This is a change in ISO C11 annex F (F.10.11p1), comparision macros can't round their arguments to their semantic type when the evaluation format has wider range and precision. (ie. they must be consistent with the builtin relational operators)
2013-07-22refactor headers, especially alltypes.h, and improve C++ ABI compatRich Felker-11/+8
the arch-specific bits/alltypes.h.sh has been replaced with a generic alltypes.h.in and minimal arch-specific bits/alltypes.h.in. this commit is intended to have no functional changes except: - exposing additional symbols that POSIX allows but does not require - changing the C++ name mangling for some types - fixing the signedness of blksize_t on powerpc (POSIX requires signed) - fixing the limit macros for sig_atomic_t on x86_64 - making dev_t an unsigned type (ABI matching goal, and more logical) in addition, some types that were wrongly defined with long on 32-bit archs were changed to int, and vice versa; this change is non-functional except for the possibility of making pointer types mismatch, and only affects programs that were using them incorrectly, and only at build-time, not runtime. the following changes were made in the interest of moving non-arch-specific types out of the alltypes system and into the headers they're associated with, and also will tend to improve application compatibility: - netdb.h now includes netinet/in.h (for socklen_t and uint32_t) - netinet/in.h now includes sys/socket.h and inttypes.h - sys/resource.h now includes sys/time.h (for struct timeval) - sys/wait.h now includes signal.h (for siginfo_t) - langinfo.h now includes nl_types.h (for nl_item) for the types in stdint.h: - types which are of no interest to other headers were moved out of the alltypes system. - fast types for 8- and 64-bit are hard-coded (at least for now); only the 16- and 32-bit ones have reason to vary by arch. and the following types have been changed for C++ ABI purposes; - mbstate_t now has a struct tag, __mbstate_t - FILE's struct tag has been changed to _IO_FILE - DIR's struct tag has been changed to __dirstream - locale_t's struct tag has been changed to __locale_struct - pthread_t is defined as unsigned long in C++ mode only - fpos_t now has a struct tag, _G_fpos64_t - fsid_t's struct tag has been changed to __fsid_t - idtype_t has been made an enum type (also required by POSIX) - nl_catd has been changed from long to void * - siginfo_t's struct tag has been removed - sigset_t's has been given a struct tag, __sigset_t - stack_t has been given a struct tag, sigaltstack - suseconds_t has been changed to long on 32-bit archs - [u]intptr_t have been changed from long to int rank on 32-bit archs - dev_t has been made unsigned summary of tests that have been performed against these changes: - nsz's libc-test (diff -u before and after) - C++ ABI check symbol dump (diff -u before, after, glibc) - grepped for __NEED, made sure types needed are still in alltypes - built gcc 3.4.6
2013-05-06remove compound literals from math.h to please c++Szabolcs Nagy-5/+10
__FLOAT_BITS and __DOUBLE_BITS macros used union compound literals, now they are changed into static inline functions. A good C compiler generates the same code for both and the later is C++ conformant.
2013-01-04add legacy header values.hrofl0r-0/+1
some programs (procps, babl) expect it, and it doesn't seem to cause any harm to just add it. it's small and straightforward. since math.h also defines MAXFLOAT, we undef it in both places, before defining it.
2012-12-11math: remove long double version of bessel functions from math.hSzabolcs Nagy-8/+0
j0l,j1l,jnl,y0l,j1l,jnl are gnu extensions, bsd and posix do not have them. noone seems to use them and there is no plan to implement them any time soon so we shouldn't declare them in math.h.
2012-12-05fix inefficiency of math.h isless, etc. macrosRich Felker-15/+30
previously, everything was going through an intermediate conversion to long double, which caused the extern __fpclassifyl function to get invoked, preventing virtually all optimizations of these operations. with the new code, tests on constant float or double arguments compile to a constant 0 or 1, and tests on non-constant expressions are efficient. I may later add support for __builtin versions on compilers that support them.
2012-09-07default features: make musl usable without feature test macrosRich Felker-3/+1
the old behavior of exposing nothing except plain ISO C can be obtained by defining __STRICT_ANSI__ or using a compiler option (such as -std=c99) that predefines it. the new default featureset is POSIX with XSI plus _BSD_SOURCE. any explicit feature test macros will inhibit the default. installation docs have also been updated to reflect this change.
2012-09-02avoid "inline" in public headers for strict c89 compatibilityRich Felker-4/+5
while musl itself requires a c99 compiler, some applications insist on being compiled with c89 compilers, and use of "inline" in the headers was breaking them. much of this had been avoided already by just skipping the inline keyword in pre-c99 compilers or modes, but this new unified solution is cleaner and may/should result in better code generation in the default gcc configuration.
2012-08-13math: fix _BSD_SOURCE namespace in math.hnsz-25/+26
2012-08-13remove significandlRich Felker-1/+0
this function never existed historically; since the float/double functions it's based on are nonstandard and deprecated, there's really no justification for its existence except that glibc has it. it can be added back if there's ever really a need...
2012-08-13add significand[fl] math functionsRich Felker-0/+4
2012-07-22fix namespace issue in prototypes in math.hRich Felker-2/+2
2012-05-22support _BSD_SOURCE feature test macroRich Felker-2/+8
patch by Isaac Dunham. matched closely (maybe not exact) to glibc's idea of what _BSD_SOURCE should make visible.
2012-05-05fix definitions of FP_ILOGB constantsRich Felker-2/+2
two issues: (1) the type was wrong (unsigned instead of signed int), and (2) the value of FP_ILOGBNAN should be INT_MIN rather than INT_MAX to match the ABI. this is also much more useful since INT_MAX corresponds to a valid input (infinity). the standard would allow us to set FP_ILOGB0 to -INT_MAX instead of INT_MIN, which would give us distinct values for ilogb(0) and ilogb(NAN), but the benefit seems way too small to justify ignoring the ABI. note that the macro is just a "portable" (to any twos complement system where signed and unsigned int have the same width) way to write INT_MIN without needing limits.h. it's valid to use this method since these macros are not required to work in #if directives.
2012-05-01support alternate glibc name pow10 for exp10Rich Felker-0/+3
2012-04-30first try at writing an efficient and "correct" exp10Rich Felker-0/+4
this is a nonstandard function so it's not clear what conditions it should satisfy. my intent is that it be fast and exact for positive integral exponents when the result fits in the destination type, and fast and correctly rounded for small negative integral exponents. otherwise we aim for at most 1ulp error; it seems to differ from pow by at most 1ulp and it's often 2-5 times faster than pow.
2012-04-18fix incorrect macro name for MATH_ERREXCEPT in math.hRich Felker-1/+1
2012-03-30optimize signbit macroRich Felker-2/+2
2012-03-30make math.h more c++-friendlyRich Felker-2/+5
2012-03-17move nonstandard gamma() etc. to _GNU_SOURCE onlyRich Felker-4/+4
it's not even provided in the library at the moment, but could easily be provided with weak aliases if desired.
2012-03-17c++ seems to want some casts in the float representation-access macrosRich Felker-2/+2
2012-03-15in math.h make lgamma_r and non-double bessel _GNU_SOURCE onlynsz-20/+18
long double and float bessel functions are no longer xsi extensions
2012-03-15efficient sincos based on sin and cosnsz-0/+4
2012-03-13first commit of the new libm!Rich Felker-9/+64
thanks to the hard work of Szabolcs Nagy (nsz), identifying the best (from correctness and license standpoint) implementations from freebsd and openbsd and cleaning them up! musl should now fully support c99 float and long double math functions, and has near-complete complex math support. tgmath should also work (fully on gcc-compatible compilers, and mostly on any c99 compiler). based largely on commit 0376d44a890fea261506f1fc63833e7a686dca19 from nsz's libm git repo, with some additions (dummy versions of a few missing long double complex functions, etc.) by me. various cleanups still need to be made, including re-adding (if they're correct) some asm functions that were dropped.
2012-03-02fix nan/infinity macros in math.h, etc.Rich Felker-6/+8
the previous version not only failed to work in c++, but also failed to produce constant expressions, making the macros useless as initializers for objects of static storage duration. gcc 3.3 and later have builtins for these, which sadly seem to be the most "portable" solution. the alternative definitions produce exceptions (for NAN) and compiler warnings (for INFINITY) on newer versions of gcc.
2012-03-02typo in math.h c version checkRich Felker-1/+1
2012-03-02make math.h compatibe with c89Rich Felker-1/+5
2012-02-15add float_t and double_t to math.hRich Felker-0/+2
2011-11-10fix all missing instances of __cplusplus checks/extern "C" in headersRich Felker-0/+8
patch by Arvid Picciani (aep)
2011-06-08isgreater etc. relation macros for math.hRich Felker-0/+18
2011-02-14extensive header cleanup for standards conformance & correctnessRich Felker-17/+19
thanks to Peter Mazinger (psm) for pointing many of these issues out and submitting a patch on which this commit is loosely based
2011-02-12initial check-in, version 0.5.0v0.5.0Rich Felker-0/+300