xref: /titanic_41/usr/src/lib/libc/amd64/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	.text
337c478bd9Sstevel@tonic-gate	.align	16
347c478bd9Sstevel@tonic-gatetwo_to_63: .4byte	0x5f000000
357c478bd9Sstevel@tonic-gate
367c478bd9Sstevel@tonic-gate	ENTRY(__xtoull)	/* 387-stack to unsigned long long */
377c478bd9Sstevel@tonic-gate	subq	$16,%rsp
387c478bd9Sstevel@tonic-gate	fstcw	cw_old(%rsp)
397c478bd9Sstevel@tonic-gate	movw	cw_old(%rsp),%ax
407c478bd9Sstevel@tonic-gate	movw	%ax,%cx
417c478bd9Sstevel@tonic-gate	andw	$0x0c00,%cx		/* save RC */
427c478bd9Sstevel@tonic-gate	orw	$0x0c00,%ax
437c478bd9Sstevel@tonic-gate	movw	%ax,cw(%rsp)
447c478bd9Sstevel@tonic-gate	fldcw	cw(%rsp)
457c478bd9Sstevel@tonic-gate	flds	two_to_63(%rip)
467c478bd9Sstevel@tonic-gate	fcomip	%st(1),%st		/* compare 2**63 to x */
477c478bd9Sstevel@tonic-gate	jp	.donotsub		/* jump if x is NaN */
487c478bd9Sstevel@tonic-gate	ja	.donotsub		/* jump if 2**63 > x */
497c478bd9Sstevel@tonic-gate	fsubs	two_to_63(%rip)		/* subtract 2**63 */
507c478bd9Sstevel@tonic-gate.donotsub:
517c478bd9Sstevel@tonic-gate	fistpll	8(%rsp)
527c478bd9Sstevel@tonic-gate	fwait				/* in case fistpll causes exception */
537c478bd9Sstevel@tonic-gate	movq	8(%rsp),%rax
547c478bd9Sstevel@tonic-gate	jp	.donotadd
557c478bd9Sstevel@tonic-gate	ja	.donotadd		/* flags did not change */
567c478bd9Sstevel@tonic-gate	movq	$0x8000000000000000,%rcx
577c478bd9Sstevel@tonic-gate	addq	%rcx,%rax		/* add back 2**63 */
587c478bd9Sstevel@tonic-gate.donotadd:
597c478bd9Sstevel@tonic-gate	fstcw	cw(%rsp)		/* fetch CW in case masks changed */
607c478bd9Sstevel@tonic-gate	movw	cw(%rsp),%dx
617c478bd9Sstevel@tonic-gate	andw	$0xf3ff,%dx
627c478bd9Sstevel@tonic-gate	orw	%cx,%dx			/* restore RC */
637c478bd9Sstevel@tonic-gate	movw	%dx,cw(%rsp)
647c478bd9Sstevel@tonic-gate	fldcw	cw(%rsp)
657c478bd9Sstevel@tonic-gate	addq	$16,%rsp
667c478bd9Sstevel@tonic-gate	ret
677c478bd9Sstevel@tonic-gate	SET_SIZE(__xtoull)
68