1/* ix87 specific implementation of arctanh function. 2 Copyright (C) 1996, 1999 Free Software Foundation, Inc. 3 This file is part of the GNU C Library. 4 Contributed by Ulrich Drepper <drepper@cygnus.com>, 1996. 5 6 The GNU C Library is free software; you can redistribute it and/or 7 modify it under the terms of the GNU Lesser General Public 8 License as published by the Free Software Foundation; either 9 version 2.1 of the License, or (at your option) any later version. 10 11 The GNU C Library is distributed in the hope that it will be useful, 12 but WITHOUT ANY WARRANTY; without even the implied warranty of 13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 14 Lesser General Public License for more details. 15 16 You should have received a copy of the GNU Lesser General Public 17 License along with the GNU C Library; if not, write to the Free 18 Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 19 02111-1307 USA. */ 20 21#include <machine/asm.h> 22 23#ifdef __ELF__ 24 .section .rodata 25#else 26 .text 27#endif 28 29 .align ALIGNARG(4) 30 ASM_TYPE_DIRECTIVE(half,@object) 31half: .double 0.5 32 ASM_SIZE_DIRECTIVE(half) 33 ASM_TYPE_DIRECTIVE(one,@object) 34one: .double 1.0 35 ASM_SIZE_DIRECTIVE(one) 36 ASM_TYPE_DIRECTIVE(limit,@object) 37limit: .double 0.29 38 ASM_SIZE_DIRECTIVE(limit) 39 ASM_TYPE_DIRECTIVE(ln2_2,@object) 40ln2_2: .tfloat 0.3465735902799726547086160 41 ASM_SIZE_DIRECTIVE(ln2_2) 42 43#ifdef PIC 44#define MO(op) op##@GOTOFF(%edx) 45#else 46#define MO(op) op 47#endif 48 49 .text 50ENTRY(__ieee754_atanh) 51 movl 8(%esp), %ecx 52 53 movl %ecx, %eax 54 andl $0x7fffffff, %eax 55 cmpl $0x7ff00000, %eax 56 jae 5f 577: 58 59#ifdef PIC 60 call 1f 611: popl %edx 62 addl $_GLOBAL_OFFSET_TABLE_+[.-1b], %edx 63#endif 64 65 andl $0x80000000, %ecx // ECX == 0 iff X >= 0 66 67 fldt MO(ln2_2) // 0.5*ln2 68 xorl %ecx, 8(%esp) 69 fldl 4(%esp) // |x| : 0.5*ln2 70 fcoml MO(half) // |x| : 0.5*ln2 71 fld %st // |x| : |x| : 0.5*ln2 72 fnstsw // |x| : |x| : 0.5*ln2 73 sahf 74 jae 2f 75 fadd %st, %st(1) // |x| : 2*|x| : 0.5*ln2 76 fld %st // |x| : |x| : 2*|x| : 0.5*ln2 77 fsubrl MO(one) // 1-|x| : |x| : 2*|x| : 0.5*ln2 78 fxch // |x| : 1-|x| : 2*|x| : 0.5*ln2 79 fmul %st(2) // 2*|x|^2 : 1-|x| : 2*|x| : 0.5*ln2 80 fdivp // (2*|x|^2)/(1-|x|) : 2*|x| : 0.5*ln2 81 faddp // 2*|x|+(2*|x|^2)/(1-|x|) : 0.5*ln2 82 fcoml MO(limit) // 2*|x|+(2*|x|^2)/(1-|x|) : 0.5*ln2 83 fnstsw // 2*|x|+(2*|x|^2)/(1-|x|) : 0.5*ln2 84 sahf 85 jae 4f 86 fyl2xp1 // 0.5*ln2*ld(1+2*|x|+(2*|x|^2)/(1-|x|)) 87 jecxz 3f 88 fchs // 0.5*ln2*ld(1+2*x+(2*x^2)/(1-x)) 893: ret 90 91 .align ALIGNARG(4) 924: faddl MO(one) // 1+2*|x|+(2*|x|^2)/(1-|x|) : 0.5*ln2 93 fyl2x // 0.5*ln2*ld(1+2*|x|+(2*|x|^2)/(1-|x|)) 94 jecxz 3f 95 fchs // 0.5*ln2*ld(1+2*x+(2*x^2)/(1-x)) 963: ret 97 98 .align ALIGNARG(4) 992: faddl MO(one) // 1+|x| : |x| : 0.5*ln2 100 fxch // |x| : 1+|x| : 0.5*ln2 101 fsubrl MO(one) // 1-|x| : 1+|x| : 0.5*ln2 102 fdivrp // (1+|x|)/(1-|x|) : 0.5*ln2 103 fyl2x // 0.5*ln2*ld((1+|x|)/(1-|x|)) 104 jecxz 3f 105 fchs // 0.5*ln2*ld((1+x)/(1-x)) 1063: ret 107 108 // x == NaN or �Inf 1095: ja 6f 110 cmpl $0, 4(%esp) 111 je 7b 1126: fldl 4(%esp) 113 ret 114END(__ieee754_atanh) 115