| /* ix87 specific implementation of arctanh function. |
| Copyright (C) 1996, 1999, 2005 Free Software Foundation, Inc. |
| This file is part of the GNU C Library. |
| Contributed by Ulrich Drepper <drepper@cygnus.com>, 1996. |
| |
| The GNU C Library is free software; you can redistribute it and/or |
| modify it under the terms of the GNU Lesser General Public |
| License as published by the Free Software Foundation; either |
| version 2.1 of the License, or (at your option) any later version. |
| |
| The GNU C Library is distributed in the hope that it will be useful, |
| but WITHOUT ANY WARRANTY; without even the implied warranty of |
| MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| Lesser General Public License for more details. |
| |
| You should have received a copy of the GNU Lesser General Public |
| License along with the GNU C Library; if not, write to the Free |
| Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA |
| 02111-1307 USA. */ |
| |
| #include <machine/asm.h> |
| |
| #ifdef __ELF__ |
| .section .rodata |
| #else |
| .text |
| #endif |
| |
| .align ALIGNARG(4) |
| ASM_TYPE_DIRECTIVE(half,@object) |
| half: .double 0.5 |
| ASM_SIZE_DIRECTIVE(half) |
| ASM_TYPE_DIRECTIVE(one,@object) |
| one: .double 1.0 |
| ASM_SIZE_DIRECTIVE(one) |
| ASM_TYPE_DIRECTIVE(limit,@object) |
| limit: .double 0.29 |
| ASM_SIZE_DIRECTIVE(limit) |
| ASM_TYPE_DIRECTIVE(ln2_2,@object) |
| ln2_2: .tfloat 0.3465735902799726547086160 |
| ASM_SIZE_DIRECTIVE(ln2_2) |
| |
| #ifdef PIC |
| #define MO(op) op##@GOTOFF(%edx) |
| #else |
| #define MO(op) op |
| #endif |
| |
| .text |
| ENTRY(__ieee754_atanh) |
| movl 8(%esp), %ecx |
| |
| movl %ecx, %eax |
| andl $0x7fffffff, %eax |
| cmpl $0x7ff00000, %eax |
| jae 5f |
| 7: |
| |
| #ifdef PIC |
| call 1f |
| cfi_adjust_cfa_offset (4) |
| 1: popl %edx |
| cfi_adjust_cfa_offset (-4) |
| addl $_GLOBAL_OFFSET_TABLE_+[.-1b], %edx |
| #endif |
| |
| andl $0x80000000, %ecx // ECX == 0 iff X >= 0 |
| |
| fldt MO(ln2_2) // 0.5*ln2 |
| xorl %ecx, 8(%esp) |
| fldl 4(%esp) // |x| : 0.5*ln2 |
| fcoml MO(half) // |x| : 0.5*ln2 |
| fld %st // |x| : |x| : 0.5*ln2 |
| fnstsw // |x| : |x| : 0.5*ln2 |
| sahf |
| jae 2f |
| fadd %st, %st(1) // |x| : 2*|x| : 0.5*ln2 |
| fld %st // |x| : |x| : 2*|x| : 0.5*ln2 |
| fsubrl MO(one) // 1-|x| : |x| : 2*|x| : 0.5*ln2 |
| fxch // |x| : 1-|x| : 2*|x| : 0.5*ln2 |
| fmul %st(2) // 2*|x|^2 : 1-|x| : 2*|x| : 0.5*ln2 |
| fdivp // (2*|x|^2)/(1-|x|) : 2*|x| : 0.5*ln2 |
| faddp // 2*|x|+(2*|x|^2)/(1-|x|) : 0.5*ln2 |
| fcoml MO(limit) // 2*|x|+(2*|x|^2)/(1-|x|) : 0.5*ln2 |
| fnstsw // 2*|x|+(2*|x|^2)/(1-|x|) : 0.5*ln2 |
| sahf |
| jae 4f |
| fyl2xp1 // 0.5*ln2*ld(1+2*|x|+(2*|x|^2)/(1-|x|)) |
| jecxz 3f |
| fchs // 0.5*ln2*ld(1+2*x+(2*x^2)/(1-x)) |
| 3: ret |
| |
| .align ALIGNARG(4) |
| 4: faddl MO(one) // 1+2*|x|+(2*|x|^2)/(1-|x|) : 0.5*ln2 |
| fyl2x // 0.5*ln2*ld(1+2*|x|+(2*|x|^2)/(1-|x|)) |
| jecxz 3f |
| fchs // 0.5*ln2*ld(1+2*x+(2*x^2)/(1-x)) |
| 3: ret |
| |
| .align ALIGNARG(4) |
| 2: faddl MO(one) // 1+|x| : |x| : 0.5*ln2 |
| fxch // |x| : 1+|x| : 0.5*ln2 |
| fsubrl MO(one) // 1-|x| : 1+|x| : 0.5*ln2 |
| fdivrp // (1+|x|)/(1-|x|) : 0.5*ln2 |
| fyl2x // 0.5*ln2*ld((1+|x|)/(1-|x|)) |
| jecxz 3f |
| fchs // 0.5*ln2*ld((1+x)/(1-x)) |
| 3: ret |
| |
| // x == NaN or ±Inf |
| 5: ja 6f |
| cmpl $0, 4(%esp) |
| je 7b |
| 6: fldl 4(%esp) |
| ret |
| END(__ieee754_atanh) |
