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+/* ix87 specific implementation of exp(x)-1.
+   Copyright (C) 1996-2017 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+   Contributed by Ulrich Drepper <drepper@cygnus.com>, 1996.
+   Based on code by John C. Bowman <bowman@ipp-garching.mpg.de>.
+   Corrections by H.J. Lu (hjl@gnu.ai.mit.edu), 1997.
+
+   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, see
+   <http://www.gnu.org/licenses/>.  */
+
+	/* Using: e^x - 1 = 2^(x * log2(e)) - 1 */
+
+#include <sysdep.h>
+#include <machine/asm.h>
+#include <i386-math-asm.h>
+
+	.section .rodata
+
+	.align ALIGNARG(4)
+	.type minus1,@object
+minus1:	.double -1.0
+	ASM_SIZE_DIRECTIVE(minus1)
+	.type one,@object
+one:	.double 1.0
+	ASM_SIZE_DIRECTIVE(one)
+	.type l2e,@object
+l2e:	.tfloat 1.442695040888963407359924681002
+	ASM_SIZE_DIRECTIVE(l2e)
+
+DEFINE_FLT_MIN
+
+#ifdef PIC
+#define MO(op) op##@GOTOFF(%edx)
+#else
+#define MO(op) op
+#endif
+
+	.text
+ENTRY(__expm1f)
+	movzwl	4+2(%esp), %eax
+	xorb	$0x80, %ah	// invert sign bit (now 1 is "positive")
+	cmpl	$0xc2b1, %eax	// is num >= 88.5?
+	jae	HIDDEN_JUMPTARGET (__expf)
+
+	flds	4(%esp)		// x
+	fxam			// Is NaN, +-Inf or +-0?
+	xorb	$0x80, %ah
+	cmpl	$0xc190, %eax	// is num <= -18.0?
+	fstsw	%ax
+	movb	$0x45, %ch
+	jb	4f
+
+	// Below -18.0 (may be -NaN or -Inf).
+	andb	%ah, %ch
+#ifdef	PIC
+	LOAD_PIC_REG (dx)
+#endif
+	cmpb	$0x01, %ch
+	je	5f		// If -NaN, jump.
+	jmp	2f		// -large, possibly -Inf.
+
+4:	// In range -18.0 to 88.5 (may be +-0 but not NaN or +-Inf).
+	andb	%ah, %ch
+	cmpb	$0x40, %ch
+	je	3f		// If +-0, jump.
+#ifdef	PIC
+	LOAD_PIC_REG (dx)
+#endif
+
+5:	fldt	MO(l2e)		// log2(e) : x
+	fmulp			// log2(e)*x
+	fld	%st		// log2(e)*x : log2(e)*x
+	// Set round-to-nearest temporarily.
+	subl	$8, %esp
+	cfi_adjust_cfa_offset (8)
+	fstcw	4(%esp)
+	movl	$0xf3ff, %ecx
+	andl	4(%esp), %ecx
+	movl	%ecx, (%esp)
+	fldcw	(%esp)
+	frndint			// int(log2(e)*x) : log2(e)*x
+	fldcw	4(%esp)
+	addl	$8, %esp
+	cfi_adjust_cfa_offset (-8)
+	fsubr	%st, %st(1)	// int(log2(e)*x) : fract(log2(e)*x)
+	fxch			// fract(log2(e)*x) : int(log2(e)*x)
+	f2xm1			// 2^fract(log2(e)*x)-1 : int(log2(e)*x)
+	fscale			// 2^(log2(e)*x)-2^int(log2(e)*x) : int(log2(e)*x)
+	fxch			// int(log2(e)*x) : 2^(log2(e)*x)-2^int(log2(e)*x)
+	fldl	MO(one)		// 1 : int(log2(e)*x) : 2^(log2(e)*x)-2^int(log2(e)*x)
+	fscale			// 2^int(log2(e)*x) : int(log2(e)*x) : 2^(log2(e)*x)-2^int(log2(e)*x)
+	fsubrl	MO(one)		// 1-2^int(log2(e)*x) : int(log2(e)*x) : 2^(log2(e)*x)-2^int(log2(e)*x)
+	fstp	%st(1)		// 1-2^int(log2(e)*x) : 2^(log2(e)*x)-2^int(log2(e)*x)
+	fsubrp	%st, %st(1)	// 2^(log2(e)*x)
+	FLT_CHECK_FORCE_UFLOW
+	ret
+
+2:	fstp	%st
+	fldl	MO(minus1)	// Set result to -1.0.
+3:	ret
+END(__expm1f)
+weak_alias (__expm1f, expm1f)