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Revision 1.6, Fri Sep 30 17:42:34 2011 UTC (9 years, 2 months ago) by christos
Branch: MAIN
CVS Tags: yamt-pagecache-tag8, yamt-pagecache-base9, yamt-pagecache-base8, yamt-pagecache-base7, yamt-pagecache-base6, yamt-pagecache-base5, yamt-pagecache-base4, yamt-pagecache-base3, yamt-pagecache-base2, yamt-pagecache-base, yamt-pagecache, riastradh-xf86-video-intel-2-7-1-pre-2-21-15, riastradh-drm2-base3, riastradh-drm2-base2, riastradh-drm2-base1, riastradh-drm2-base, riastradh-drm2, netbsd-6-base, netbsd-6-1-RELEASE, netbsd-6-1-RC4, netbsd-6-1-RC3, netbsd-6-1-RC2, netbsd-6-1-RC1, netbsd-6-1-5-RELEASE, netbsd-6-1-4-RELEASE, netbsd-6-1-3-RELEASE, netbsd-6-1-2-RELEASE, netbsd-6-1-1-RELEASE, netbsd-6-1, netbsd-6-0-RELEASE, netbsd-6-0-RC2, netbsd-6-0-RC1, netbsd-6-0-6-RELEASE, netbsd-6-0-5-RELEASE, netbsd-6-0-4-RELEASE, netbsd-6-0-3-RELEASE, netbsd-6-0-2-RELEASE, netbsd-6-0-1-RELEASE, netbsd-6-0, netbsd-6, matt-nb6-plus-nbase, matt-nb6-plus-base, matt-nb6-plus, agc-symver-base, agc-symver
Branch point for: tls-maxphys, tls-earlyentropy
Changes since 1.5: +6 -4 lines

PR/44293: Paul Goyette: Fix the mess of the rounding code.

/*	$NetBSD: flt_rounds.S,v 1.6 2011/09/30 17:42:34 christos Exp $	*/

#include <machine/asm.h>

/*
 * 00 0 round to zero 
 * 01 1 round to nearest
 * 10 2 round to positive infinity
 * 11 3 round to negative infinity
 */
	.text
	_ALIGN_TEXT
ENTRY(__flt_rounds)
	fnstcw	-4(%rsp)
	movl	-4(%rsp), %ecx
	shrl	$9, %ecx
	andl	$6, %ecx
	movl	$0x2d, %eax	/* 0x2d = 00.10.11.01 */
	sarl	%cl, %eax	/* 0,1,2,3 -> 1,3,2,0 */
	andl	$3, %eax
	ret