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-rw-r--r--sysdeps/i386/fpu/e_atanhf.S102
1 files changed, 102 insertions, 0 deletions
diff --git a/sysdeps/i386/fpu/e_atanhf.S b/sysdeps/i386/fpu/e_atanhf.S
new file mode 100644
index 0000000000..687d4c97fb
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+++ b/sysdeps/i386/fpu/e_atanhf.S
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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)
+	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)
+	.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_atanhf)
+	movl	4(%esp), %ecx
+
+#ifdef PIC
+	call	1f
+1:	popl	%edx
+	addl	$_GLOBAL_OFFSET_TABLE_+[.-1b], %edx
+#endif
+
+	andl	$0x80000000, %ecx // ECX == 0 iff X >= 0
+
+	fldt	MO(ln2_2)	// 0.5*ln2
+	xorl	%ecx, 4(%esp)
+	flds	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_atanhf)