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+/* ix87 specific implementation of arctanh function.
+ Copyright (C) 1996 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 Library General Public License as
+ published by the Free Software Foundation; either version 2 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
+ Library General Public License for more details.
+
+ You should have received a copy of the GNU Library General Public
+ License along with the GNU C Library; see the file COPYING.LIB. 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)
+ /* Please note that we use double values for 0.5 and 1.0. These
+ numbers have exact representations and so we don't get accuracy
+ problems. The advantage is that the code is simpler. */
+ 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)
+ /* 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. */
+ ASM_TYPE_DIRECTIVE(limit,@object)
+limit: .double 0.29
+ ASM_SIZE_DIRECTIVE(limit)
+ .align ALIGNARG(4)
+ 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_atanhl)
+ movl 12(%esp), %ecx
+
+#ifdef PIC
+ call 1f
+1: popl %edx
+ addl $_GLOBAL_OFFSET_TABLE_+[.-1b], %edx
+#endif
+
+ andl $0x8000, %ecx // ECX == 0 iff X >= 0
+
+ fldt MO(ln2_2) // 0.5*ln2
+ xorl %ecx, 12(%esp)
+ fldt 4(%esp) // |x| : 0.5*ln2
+ fcoml MO(half) // |x| : 0.5*ln2
+ fld %st(0) // |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
+END(__ieee754_atanhl)