xref: /titanic_41/usr/src/lib/libc/i386/fp/_xtoull.s (revision 9a70fc3be3b1e966bf78825cdb8d509963a6f0a1)
17c478bd9Sstevel@tonic-gate/*
27c478bd9Sstevel@tonic-gate * CDDL HEADER START
37c478bd9Sstevel@tonic-gate *
47c478bd9Sstevel@tonic-gate * The contents of this file are subject to the terms of the
5*9a70fc3bSMark J. Nelson * Common Development and Distribution License (the "License").
6*9a70fc3bSMark J. Nelson * You may not use this file except in compliance with the License.
77c478bd9Sstevel@tonic-gate *
87c478bd9Sstevel@tonic-gate * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
97c478bd9Sstevel@tonic-gate * or http://www.opensolaris.org/os/licensing.
107c478bd9Sstevel@tonic-gate * See the License for the specific language governing permissions
117c478bd9Sstevel@tonic-gate * and limitations under the License.
127c478bd9Sstevel@tonic-gate *
137c478bd9Sstevel@tonic-gate * When distributing Covered Code, include this CDDL HEADER in each
147c478bd9Sstevel@tonic-gate * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
157c478bd9Sstevel@tonic-gate * If applicable, add the following below this CDDL HEADER, with the
167c478bd9Sstevel@tonic-gate * fields enclosed by brackets "[]" replaced with your own identifying
177c478bd9Sstevel@tonic-gate * information: Portions Copyright [yyyy] [name of copyright owner]
187c478bd9Sstevel@tonic-gate *
197c478bd9Sstevel@tonic-gate * CDDL HEADER END
207c478bd9Sstevel@tonic-gate */
217c478bd9Sstevel@tonic-gate/*
227c478bd9Sstevel@tonic-gate * Copyright 2004 Sun Microsystems, Inc.  All rights reserved.
237c478bd9Sstevel@tonic-gate * Use is subject to license terms.
247c478bd9Sstevel@tonic-gate */
257c478bd9Sstevel@tonic-gate
26*9a70fc3bSMark J. Nelson	.file	"_xtoull.s"
277c478bd9Sstevel@tonic-gate
287c478bd9Sstevel@tonic-gate#include <SYS.h>
297c478bd9Sstevel@tonic-gate
307c478bd9Sstevel@tonic-gate	.set	cw,0
317c478bd9Sstevel@tonic-gate	.set	cw_old,2
327c478bd9Sstevel@tonic-gate	.set	two_words,4
337c478bd9Sstevel@tonic-gate	.set	four_words,8
347c478bd9Sstevel@tonic-gate	.text
357c478bd9Sstevel@tonic-gate	.align	4
367c478bd9Sstevel@tonic-gatetwo_to_63: .long	0x5f000000
377c478bd9Sstevel@tonic-gate
387c478bd9Sstevel@tonic-gate	ENTRY(__xtoull)	// 387-stack to unsigned long long
397c478bd9Sstevel@tonic-gate	subl	$12,%esp
407c478bd9Sstevel@tonic-gate	fstcw	cw_old(%esp)
417c478bd9Sstevel@tonic-gate	movw	cw_old(%esp),%ax
427c478bd9Sstevel@tonic-gate	movw	%ax,%cx
437c478bd9Sstevel@tonic-gate	andw	$0x0c00,%cx		// save RC
447c478bd9Sstevel@tonic-gate	orw	$0x0c00,%ax
457c478bd9Sstevel@tonic-gate	movw	%ax,cw(%esp)
467c478bd9Sstevel@tonic-gate	fldcw	cw(%esp)
477c478bd9Sstevel@tonic-gate	_prologue_
487c478bd9Sstevel@tonic-gate	fcoms	_sref_(two_to_63)	// compare st to 2**63
497c478bd9Sstevel@tonic-gate	_epilogue_
507c478bd9Sstevel@tonic-gate	fstsw	%ax			// store status in %ax
517c478bd9Sstevel@tonic-gate					// use fstsw for correct trap handling
527c478bd9Sstevel@tonic-gate	sahf				// load AH into flags
537c478bd9Sstevel@tonic-gate	jb	.donotsub		// jump if st < 2**63 or is NaN
547c478bd9Sstevel@tonic-gate	_prologue_
557c478bd9Sstevel@tonic-gate	fsubs	_sref_(two_to_63)	// subtract 2**63
567c478bd9Sstevel@tonic-gate	_epilogue_
577c478bd9Sstevel@tonic-gate.donotsub:
587c478bd9Sstevel@tonic-gate	fistpll	two_words(%esp)
597c478bd9Sstevel@tonic-gate	fwait				// in case fistpll causes exception
607c478bd9Sstevel@tonic-gate	movl	four_words(%esp),%edx
617c478bd9Sstevel@tonic-gate	jb	.donotadd		// flags did not change
627c478bd9Sstevel@tonic-gate	add	$0x80000000,%edx	// add back 2**63
637c478bd9Sstevel@tonic-gate.donotadd:
647c478bd9Sstevel@tonic-gate	fstcw	cw(%esp)		// fetch CW in case masks changed value
657c478bd9Sstevel@tonic-gate	movw	cw(%esp),%ax
667c478bd9Sstevel@tonic-gate	andw	$0xf3ff,%ax
677c478bd9Sstevel@tonic-gate	orw	%cx,%ax			// restore RC
687c478bd9Sstevel@tonic-gate	movw	%ax,cw(%esp)
697c478bd9Sstevel@tonic-gate	fldcw	cw(%esp)
707c478bd9Sstevel@tonic-gate	movl	two_words(%esp),%eax
717c478bd9Sstevel@tonic-gate	addl	$12,%esp
727c478bd9Sstevel@tonic-gate	ret
737c478bd9Sstevel@tonic-gate	SET_SIZE(__xtoull)
74