mirror of
https://sourceware.org/git/glibc.git
synced 2024-11-25 14:30:06 +00:00
114e299ca6
Some compiler does not support it (such as clang integrated assembler) neither gcc emits it.
73 lines
1.1 KiB
ArmAsm
73 lines
1.1 KiB
ArmAsm
/*
|
|
* Public domain.
|
|
*
|
|
*/
|
|
|
|
#include <machine/asm.h>
|
|
|
|
RCSID("$NetBSD: s_log1p.S,v 1.7 1995/05/09 00:10:58 jtc Exp $")
|
|
|
|
.section .rodata
|
|
|
|
.align ALIGNARG(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: .quad 0x947ae147ae147ae1 /* 0.29 */
|
|
.short 0x3ffd
|
|
/* Please note: we use a double value here. Since 1.0 has
|
|
an exact representation this does not effect the accuracy
|
|
but it helps to optimize the code. */
|
|
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.
|
|
*/
|
|
#ifdef PIC
|
|
#define MO(op) op##(%rip)
|
|
#else
|
|
#define MO(op) op
|
|
#endif
|
|
|
|
.text
|
|
ENTRY(__log1pl)
|
|
fldln2
|
|
|
|
fldt 8(%rsp)
|
|
|
|
fxam
|
|
fnstsw
|
|
fld %st
|
|
testb $1, %ah
|
|
jnz 3f // in case x is NaN or ±Inf
|
|
4:
|
|
fabs
|
|
fldt MO(limit)
|
|
fcompp
|
|
fnstsw
|
|
andb $1,%ah
|
|
jz 2f
|
|
|
|
movzwl 8+8(%rsp), %eax
|
|
xorb $0x80, %ah
|
|
cmpl $0xc040, %eax
|
|
jae 5f
|
|
|
|
faddl MO(one)
|
|
5: fyl2x
|
|
ret
|
|
|
|
2: fyl2xp1
|
|
ret
|
|
|
|
3: testb $4, %ah
|
|
jnz 4b // in case x is ±Inf
|
|
fstp %st(1)
|
|
fstp %st(1)
|
|
fadd %st(0)
|
|
ret
|
|
|
|
END (__log1pl)
|