long doubles (i386, amd64, ia64) and one for machines with 128-bit
long doubles (sparc64). Other platforms use the double version.
I've only done runtime testing on i386.
Thanks to bde@ for helpful discussions and bugfixes.
adds two new directories in msun: ld80 and ld128. These are for
long double functions specific to the 80-bit long double format
used on x86-derived architectures, and the 128-bit format used on
sparc64, respectively.
sparc64's 128-bit long doubles.
- Define FP_FAST_FMAL for ia64.
- Prototypes for fmal, frexpl, ldexpl, nextafterl, nexttoward{,f,l},
scalblnl, and scalbnl.
flags, so they are not pure. Remove the __pure2 annotation from them.
I believe that the following routines and their float and long double
counterparts are the only ones here that can be __pure2:
copysign is* fabs finite fmax fmin fpclassify ilogb nan signbit
When gcc supports FENV_ACCESS, perhaps there will be a new annotation
that allows the other functions to be considered pure when FENV_ACCESS
is off.
Discussed with: bde
basically support this, subject to gcc's lack of FENV_ACCESS support.
In any case, the previous setting of math_errhandling to 0 is not
allowed by POSIX.
- It was added to libc instead of libm. Hopefully no programs rely
on this mistake.
- It didn't work properly on large long doubles because its argument
was converted to type double, resulting in undefined behavior.
- Unlike the builtin relational operators, builtin floating-point
constants were not available until gcc 3.3, so account for this.[1]
- Apparently some versions of the Intel C Compiler fallaciously define
__GNUC__ without actually being compatible with the claimed gcc
version. Account for this, too.[2]
[1] Noticed by: Christian Hiris <4711@chello.at>
[2] Submitted by: Alexander Leidinger <Alexander@Leidinger.net>
isnormal() the hard way, rather than relying on fpclassify(). This is
a lose in the sense that we need a total of 12 functions, but it is
necessary for binary compatibility because we have never bumped libm's
major version number. In particular, isinf(), isnan(), and isnanf()
were BSD libc functions before they were C99 macros, so we can't
reimplement them in terms of fpclassify() without adding a dependency
on libc.so.5. I have tried to arrange things so that programs that
could be compiled in FreeBSD 4.X will generate the same external
references when compiled in 5.X. At the same time, the new macros
should remain C99-compliant.
The isinf() and isnan() functions remain in libc for historical
reasons; however, I have moved the functions that implement the macros
isfinite() and isnormal() to libm where they belong. Moreover,
half a dozen MD versions of isinf() and isnan() have been replaced
with MI versions that work equally well.
Prodded by: kris
builtins are available: HUGE_VAL, HUGE_VALF, HUGE_VALL, INFINITY,
and NAN. These macros now expand to floating-point constant
expressions rather than external references, as required by C99.
Other compilers will retain the historical behavior. Note that
it is not possible say, e.g.
#define HUGE_VAL 1.0e9999
because the above may result in diagnostics at translation time
and spurious exceptions at runtime. Hence the need for compiler
support for these features.
Also use builtins to implement the macros isgreater(),
isgreaterequal(), isless(), islessequal(), islessgreater(),
and isunordered() when such builtins are available.
Although the old macros are correct, the builtin versions
are much faster, and they avoid double-expansion problems.
These trivial implementations are about 25 times slower than
rint{,f}() on x86 due to the FP environment save/restore.
They should eventually be redone in terms of fegetround() and
bit fiddling.
namespaces are visible. Previously, math.h failed to hide some C99-,
XSI-, and BSD-specific symbols in certain compilation environments.
The referenced PR has a nice listing of the appropriate conditions for
making symbols visible in math.h. The only non-stylistic difference
between the patch in the PR and this commit is that I superfluously
test for __BSD_VISIBLE in a few places to be more explicit about which
symbols have historically been part of the FreeBSD environment.
PR: 65939
Submitted by: Stefan Farfeleder <stefan@fafoe.narf.at>
MATH_ERREXCEPTION and math_errhandling, so that C99 applications at
least have the possibility of determining that errno is not set for
math functions. Set math_errhandling to the non-standard-conforming
value of 0 for now to indicate that we don't support either method
of reporting errors. We intentionally don't support MATH_ERRNO
because errno is a mistake, and we are missing support for
MATH_ERREXCEPTION (<fenv.h>, compiler support for <fenv.h>, and
actually setting the exception flags correctly).
