newlib-cygwin/winsup/cygwin/math/log10l.S

94 lines
1.9 KiB
ArmAsm

/**
* This file has no copyright assigned and is placed in the Public Domain.
* This file is part of the mingw-w64 runtime package.
* No warranty is given; refer to the file DISCLAIMER.PD within this package.
*/
#include <_mingw_mac.h>
.file "log10l.S"
.text
#ifdef __x86_64__
.align 8
#else
.align 4
#endif
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
#ifdef __x86_64__
.align 8
#else
.align 4
#endif
.globl __MINGW_USYMBOL(log10l)
.def __MINGW_USYMBOL(log10l); .scl 2; .type 32; .endef
__MINGW_USYMBOL(log10l):
#ifdef __x86_64__
fldlg2 // log10(2)
fldt (%rdx) // x : log10(2)
fxam
fnstsw
fld %st // x : x : log10(2)
sahf
jc 3f // in case x is NaN or ±Inf
4: fsubl one(%rip) // x-1 : x : log10(2)
fld %st // x-1 : x-1 : x : log10(2)
fabs // |x-1| : x-1 : x : log10(2)
fcompl limit(%rip) // 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)
movq %rcx,%rax
movq $0,8(%rcx)
fstpt (%rcx)
ret
2: fstp %st(0) // x : log10(2)
fyl2x // log10(x)
movq %rcx,%rax
movq $0,8(%rcx)
fstpt (%rcx)
ret
3: jp 4b // in case x is ±Inf
fstp %st(1)
fstp %st(1)
movq %rcx,%rax
movq $0,8(%rcx)
fstpt (%rcx)
ret
#else
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
#endif