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/**
* 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 "log2l.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
.globl __MINGW_USYMBOL(log2l)
.def __MINGW_USYMBOL(log2l); .scl 2; .type 32; .endef
__MINGW_USYMBOL(log2l):
#ifdef __x86_64__
fldl one(%rip)
fldt (%rdx) // x : 1
fxam
fnstsw
fld %st // x : x : 1
sahf
jc 3f // in case x is NaN or Inf
4: fsub %st(2), %st // x-1 : x : 1
fld %st // x-1 : x-1 : x : 1
fabs // |x-1| : x-1 : x : 1
fcompl limit(%rip) // x-1 : x : 1
fnstsw // x-1 : x : 1
andb $0x45, %ah
jz 2f
fstp %st(1) // x-1 : 1
fyl2xp1 // log(x)
movq %rcx,%rax
movq $0,8(%rcx)
fstpt (%rcx)
ret
2: fstp %st(0) // x : 1
fyl2x // log(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
fldl one
fldt 4(%esp) // x : 1
fxam
fnstsw
fld %st // x : x : 1
sahf
jc 3f // in case x is NaN or Inf
4: fsub %st(2), %st // x-1 : x : 1
fld %st // x-1 : x-1 : x : 1
fabs // |x-1| : x-1 : x : 1
fcompl limit // x-1 : x : 1
fnstsw // x-1 : x : 1
andb $0x45, %ah
jz 2f
fstp %st(1) // x-1 : 1
fyl2xp1 // log(x)
ret
2: fstp %st(0) // x : 1
fyl2x // log(x)
ret
3: jp 4b // in case x is Inf
fstp %st(1)
fstp %st(1)
ret
#endif
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