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1/*
2 * Written by J.T. Conklin <jtc@netbsd.org>.
3 * Public domain.
4 *
5 * Adapted for `long double' by Ulrich Drepper <drepper@cygnus.com>.
6 */
7
8#include <machine/asm.h>
9
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10
11#ifdef __ELF__
0ac5ae23 12 .section .rodata.cst8,"aM",@progbits,8
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13#else
14 .text
15#endif
0ac5ae23 16 .p2align 3
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17 ASM_TYPE_DIRECTIVE(one,@object)
18one: .double 1.0
19 ASM_SIZE_DIRECTIVE(one)
20 /* It is not important that this constant is precise. It is only
21 a value which is known to be on the safe side for using the
22 fyl2xp1 instruction. */
23 ASM_TYPE_DIRECTIVE(limit,@object)
24limit: .double 0.29
25 ASM_SIZE_DIRECTIVE(limit)
26
27
28#ifdef PIC
0ac5ae23 29# define MO(op) op##@GOTOFF(%edx)
d38cd08c 30#else
0ac5ae23 31# define MO(op) op
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32#endif
33
34 .text
ee188d55 35ENTRY(__ieee754_logl)
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36 fldln2 // log(2)
37 fldt 4(%esp) // x : log(2)
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38 fxam
39 fnstsw
d38cd08c 40#ifdef PIC
fee732e5 41 LOAD_PIC_REG (dx)
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42#endif
43 fld %st // x : x : log(2)
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44 sahf
45 jc 3f // in case x is NaN or +-Inf
464: fsubl MO(one) // x-1 : x : log(2)
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47 fld %st // x-1 : x-1 : x : log(2)
48 fabs // |x-1| : x-1 : x : log(2)
49 fcompl MO(limit) // x-1 : x : log(2)
50 fnstsw // x-1 : x : log(2)
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51 andb $0x45, %ah
52 jz 2f
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53 fstp %st(1) // x-1 : log(2)
54 fyl2xp1 // log(x)
55 ret
56
6bc31da0 572: fstp %st(0) // x : log(2)
d38cd08c 58 fyl2x // log(x)
ee188d55 59 ret
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60
613: jp 4b // in case x is +-Inf
62 fstp %st(1)
63 fstp %st(1)
64 ret
d38cd08c 65END (__ieee754_logl)
0ac5ae23 66strong_alias (__ieee754_logl, __logl_finite)