picnoir/glibc
1
0
Fork 0
Code Issues Pull requests Packages Projects Releases Wiki Activity

Clean up some complex functions raising FE_INVALID.

Browse source 
Some of the complex arithmetic functions have the following pattern:
in some piece of code, one part of the input (real or imaginary,
depending on the function) is either infinite or NaN.  Part of the
result is to be set to NaN in either case, and FE_INVALID raised only
if the relevant part of the input was infinite.

In such a case, there is no actual need for the conditional on the
type of the input, since subtracting the relevant part of the input
from itself will produce a NaN, with FE_INVALID only if the relevant
part of the input was infinite.  This simplifies the code, and as a
quality-of-implementation matter also improves things by propagating
NaN payloads.  (Right now these functions always raise FE_INVALID for
signaling NaN arguments because of the call to fpclassify - at least
unless glibc is built with -Os - but if fpclassify moves to using
integer arithmetic in future, doing arithmetic on the NaN argument
also ensures an exception for sNaNs.)

Tested for x86_64 and x86.

	* math/s_ccosh_template.c (M_DECL_FUNC (__ccosh)): Instead of
	raising FE_INVALID with feraisexcept in case where part of
	argument is infinite, subtract that part of argument from itself.
	* math/s_cexp_template.c (M_DECL_FUNC (__cexp)): Likewise.
	* math/s_csin_template.c (M_DECL_FUNC (__csin)): Likewise.
	* math/s_csinh_template.c (M_DECL_FUNC (__csinh)): Likewise.
This commit is contained in:
Joseph Myers 2016-10-14 00:12:56 +00:00
parent 07c18a008c
commit e886c36771
5 changed files with 16 additions and 29 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

9
ChangeLog
View file

@ -1,3 +1,12 @@
2016-10-13 Joseph Myers <joseph@codesourcery.com>
* math/s_ccosh_template.c (M_DECL_FUNC (__ccosh)): Instead of
raising FE_INVALID with feraisexcept in case where part of
argument is infinite, subtract that part of argument from itself.
* math/s_cexp_template.c (M_DECL_FUNC (__cexp)): Likewise.
* math/s_csin_template.c (M_DECL_FUNC (__csin)): Likewise.
* math/s_csinh_template.c (M_DECL_FUNC (__csinh)): Likewise.
2016-10-12 Joseph Myers <joseph@codesourcery.com>
* math/libm-test.inc (totalorder_test_data): Add more tests.

10
math/s_ccosh_template.c
View file

@ -88,10 +88,7 @@ M_DECL_FUNC (__ccosh) (CFLOAT x)
else
{
__imag__ retval = __real__ x == 0 ? 0 : M_NAN;
__real__ retval = M_NAN;
if (icls == FP_INFINITE)
feraiseexcept (FE_INVALID);
__real__ retval = __imag__ x - __imag__ x;
}
}
else if (rcls == FP_INFINITE)
@ -125,10 +122,7 @@ M_DECL_FUNC (__ccosh) (CFLOAT x)
else
{
__real__ retval = M_HUGE_VAL;
__imag__ retval = M_NAN;
if (icls == FP_INFINITE)
feraiseexcept (FE_INVALID);
__imag__ retval = __imag__ x - __imag__ x;
}
}
else

5
math/s_cexp_template.c
View file

@ -121,10 +121,7 @@ M_DECL_FUNC (__cexp) (CFLOAT x)
else if (signbit (__real__ x) == 0)
{
__real__ retval = M_HUGE_VAL;
__imag__ retval = M_NAN;
if (icls == FP_INFINITE)
feraiseexcept (FE_INVALID);
__imag__ retval = __imag__ x - __imag__ x;
}
else
{

11
math/s_csin_template.c
View file

@ -96,11 +96,8 @@ M_DECL_FUNC (__csin) (CFLOAT x)
if (icls == FP_ZERO)
{
/* Imaginary part is 0.0. */
__real__ retval = M_NAN;
__real__ retval = __real__ x - __real__ x;
__imag__ retval = __imag__ x;
if (rcls == FP_INFINITE)
feraiseexcept (FE_INVALID);
}
else
{
@ -145,12 +142,8 @@ M_DECL_FUNC (__csin) (CFLOAT x)
}
else
{
/* The addition raises the invalid exception. */
__real__ retval = M_NAN;
__real__ retval = __real__ x - __real__ x;
__imag__ retval = M_HUGE_VAL;
if (rcls == FP_INFINITE)
feraiseexcept (FE_INVALID);
}
}
else

10
math/s_csinh_template.c
View file

@ -97,10 +97,7 @@ M_DECL_FUNC (__csinh) (CFLOAT x)
{
/* Real part is 0.0. */
__real__ retval = M_COPYSIGN (0, negate ? -1 : 1);
__imag__ retval = M_NAN;
if (icls == FP_INFINITE)
feraiseexcept (FE_INVALID);
__imag__ retval = __imag__ x - __imag__ x;
}
else
{
@ -144,10 +141,7 @@ M_DECL_FUNC (__csinh) (CFLOAT x)
else
{
__real__ retval = M_HUGE_VAL;
__imag__ retval = M_NAN;
if (icls == FP_INFINITE)
feraiseexcept (FE_INVALID);
__imag__ retval = __imag__ x - __imag__ x;
}
}
else