/* * Written by J.T. Conklin <jtc@netbsd.org>. * Public domain. * * Adapted for `long double' by Ulrich Drepper <drepper@cygnus.com>. * * Changed to use fyl2xp1 for values near 1, <drepper@cygnus.com>. * * Removed header file dependency for use in libmingwex.a by * Danny Smith <dannysmith@users.sourceforge.net> */ .file "log10l.S" .text .align 4 one: .double 1.0 /* It is not important that this constant is precise. It is only a value which is known to be on the safe side for using the fyl2xp1 instruction. */ limit: .double 0.29 .text .align 4 .globl _log10l .def _log10l; .scl 2; .type 32; .endef _log10l: fldlg2 /* log10(2) */ fldt 4(%esp) /* x : log10(2) */ fxam fnstsw fld %st /* x : x : log10(2) */ sahf jc 3f /* in case x is NaN or ±Inf */ 4: fsubl one /* x-1 : x : log10(2) */ fld %st /* x-1 : x-1 : x : log10(2) */ fabs /* |x-1| : x-1 : x : log10(2) */ fcompl limit /* x-1 : x : log10(2) */ fnstsw /* x-1 : x : log10(2) */ andb $0x45, %ah jz 2f fstp %st(1) /* x-1 : log10(2) */ fyl2xp1 /* log10(x) */ ret 2: fstp %st(0) /* x : log10(2) */ fyl2x /* log10(x) */ ret 3: jp 4b /* in case x is ±Inf */ fstp %st(1) fstp %st(1) ret