2001-09-19 10:37:31 +00:00
|
|
|
/*
|
|
|
|
* Written by J.T. Conklin <jtc@netbsd.org>.
|
|
|
|
* Public domain.
|
|
|
|
*
|
|
|
|
* Adapted for `long double' by Ulrich Drepper <drepper@cygnus.com>.
|
|
|
|
* Adapted for x86-64 by Andreas Jaeger <aj@suse.de>.
|
|
|
|
*/
|
|
|
|
|
|
|
|
#include <machine/asm.h>
|
2019-07-16 15:17:22 +00:00
|
|
|
#include <libm-alias-finite.h>
|
2001-09-19 10:37:31 +00:00
|
|
|
|
2011-10-12 15:27:51 +00:00
|
|
|
.section .rodata.cst8,"aM",@progbits,8
|
2012-02-06 23:41:11 +00:00
|
|
|
|
2011-10-12 15:27:51 +00:00
|
|
|
.p2align 3
|
2012-08-02 19:04:29 +00:00
|
|
|
.type one,@object
|
2001-09-19 10:37:31 +00:00
|
|
|
one: .double 1.0
|
|
|
|
ASM_SIZE_DIRECTIVE(one)
|
|
|
|
/* 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. */
|
2012-08-02 19:04:29 +00:00
|
|
|
.type limit,@object
|
2001-09-19 10:37:31 +00:00
|
|
|
limit: .double 0.29
|
|
|
|
ASM_SIZE_DIRECTIVE(limit)
|
|
|
|
|
|
|
|
|
|
|
|
#ifdef PIC
|
2011-10-12 15:27:51 +00:00
|
|
|
# define MO(op) op##(%rip)
|
2001-09-19 10:37:31 +00:00
|
|
|
#else
|
2011-10-12 15:27:51 +00:00
|
|
|
# define MO(op) op
|
2001-09-19 10:37:31 +00:00
|
|
|
#endif
|
|
|
|
|
|
|
|
.text
|
|
|
|
ENTRY(__ieee754_logl)
|
|
|
|
fldln2 // log(2)
|
|
|
|
fldt 8(%rsp) // x : log(2)
|
2007-03-15 20:10:51 +00:00
|
|
|
fxam
|
|
|
|
fnstsw
|
2001-09-19 10:37:31 +00:00
|
|
|
fld %st // x : x : log(2)
|
2007-03-15 20:10:51 +00:00
|
|
|
testb $1, %ah
|
|
|
|
jnz 3f // in case x is NaN or +-Inf
|
2014-06-18 12:32:01 +00:00
|
|
|
movzwl 8+8(%rsp), %eax
|
|
|
|
cmpl $0xc000, %eax
|
|
|
|
jae 6f // x <= -2, avoid overflow from -LDBL_MAX - 1.
|
2007-03-15 20:10:51 +00:00
|
|
|
4: fsubl MO(one) // x-1 : x : log(2)
|
2014-06-18 12:32:01 +00:00
|
|
|
6: fld %st // x-1 : x-1 : x : log(2)
|
2001-09-19 10:37:31 +00:00
|
|
|
fabs // |x-1| : x-1 : x : log(2)
|
|
|
|
fcompl MO(limit) // x-1 : x : log(2)
|
|
|
|
fnstsw // x-1 : x : log(2)
|
|
|
|
andb $0x45, %ah
|
|
|
|
jz 2f
|
2014-03-21 18:13:58 +00:00
|
|
|
fxam
|
|
|
|
fnstsw
|
|
|
|
andb $0x45, %ah
|
|
|
|
cmpb $0x40, %ah
|
|
|
|
jne 5f
|
|
|
|
fabs // log(1) is +0 in all rounding modes.
|
|
|
|
5: fstp %st(1) // x-1 : log(2)
|
2001-09-19 10:37:31 +00:00
|
|
|
fyl2xp1 // log(x)
|
|
|
|
ret
|
|
|
|
|
|
|
|
2: fstp %st(0) // x : log(2)
|
|
|
|
fyl2x // log(x)
|
|
|
|
ret
|
2007-03-15 20:10:51 +00:00
|
|
|
|
|
|
|
3: testb $4, %ah
|
|
|
|
jnz 4b // in case x is +-Inf
|
|
|
|
fstp %st(1)
|
|
|
|
fstp %st(1)
|
2016-06-08 22:24:06 +00:00
|
|
|
fadd %st(0)
|
2007-03-15 20:10:51 +00:00
|
|
|
ret
|
2001-09-19 10:37:31 +00:00
|
|
|
END (__ieee754_logl)
|
2011-10-12 15:27:51 +00:00
|
|
|
|
|
|
|
|
|
|
|
ENTRY(__logl_finite)
|
|
|
|
fldln2 // log(2)
|
|
|
|
fldt 8(%rsp) // x : log(2)
|
|
|
|
fld %st // x : x : log(2)
|
|
|
|
fsubl MO(one) // x-1 : x : log(2)
|
|
|
|
fld %st // x-1 : x-1 : x : log(2)
|
|
|
|
fabs // |x-1| : x-1 : x : log(2)
|
|
|
|
fcompl MO(limit) // x-1 : x : log(2)
|
|
|
|
fnstsw // x-1 : x : log(2)
|
|
|
|
andb $0x45, %ah
|
|
|
|
jz 2b
|
2015-11-05 21:56:31 +00:00
|
|
|
fxam
|
|
|
|
fnstsw
|
|
|
|
andb $0x45, %ah
|
|
|
|
cmpb $0x40, %ah
|
|
|
|
jne 7f
|
|
|
|
fabs // log(1) is +0 in all rounding modes.
|
|
|
|
7: fstp %st(1) // x-1 : log(2)
|
2011-10-12 15:27:51 +00:00
|
|
|
fyl2xp1 // log(x)
|
|
|
|
ret
|
|
|
|
END (__logl_finite)
|
2019-07-16 15:17:22 +00:00
|
|
|
libm_alias_finite (__logl_finite, __logl)
|