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Revision 1.4, Fri Sep 30 17:42:34 2011 UTC (9 years, 5 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 1.3: +14 -20 lines

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

/*	$NetBSD: fpsetround.S,v 1.4 2011/09/30 17:42:34 christos Exp $	*/

 * Written by Frank van der Linden at Wasabi Systems for NetBSD.
 * Public domain.

#include <machine/asm.h>

 * XXX set both the x87 control word and the SSE mxcsr register.
 * Applications should only set exception and round flags
 * via the fp*() interface, otherwise the status words
 * will get our of sync.

WEAK_ALIAS(fpsetround, _fpsetround)

	fnstcw	-4(%rsp)
	movl	-4(%rsp), %edx
	movl	%edx, %eax
	andl	$0x00000c00, %eax	
	andl	$0xfffff3ff, %edx
	orl	%edi, %edx
	movl	%edx, -4(%rsp)
	fldcw	-4(%rsp)

	stmxcsr	-4(%rsp)
	movl	-4(%rsp), %edx
	andl	$0xffff9fff, %edx
	sall	$3, %edi
	orl	%edi,%edx
	movl	%edx,-4(%rsp)
	ldmxcsr	-4(%rsp)