newlib/winsup/mingw/mingwex/math/log1p.S

48 lines
817 B
ArmAsm

/*
* Written by J.T. Conklin <jtc@netbsd.org>.
* Public domain.
* Removed header file dependency for use in libmingwex.a by
* Danny Smith <dannysmith@users.sourceforge.net>
*/
.file "log1p.S"
.text
.align 4
/* The fyl2xp1 can only be used for values in
-1 + sqrt(2) / 2 <= x <= 1 - sqrt(2) / 2
0.29 is a safe value.
*/
limit: .double 0.29
one: .double 1.0
/*
* Use the fyl2xp1 function when the argument is in the range -0.29 to 0.29,
* otherwise fyl2x with the needed extra computation.
*/
.globl _log1p;
.def _log1p; .scl 2; .type 32; .endef
_log1p:
fldln2
fldl 4(%esp)
fxam
fnstsw
fld %st
sahf
jc 3f /* in case x is NaN or ±Inf */
4: fabs
fcompl limit
fnstsw
sahf
jc 2f
faddl one
fyl2x
ret
2: fyl2xp1
ret
3: jp 4b /* in case x is ±Inf */
fstp %st(1)
fstp %st(1)
ret