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diff --git a/sysdeps/i386/fpu/s_floor.S b/sysdeps/i386/fpu/s_floor.S
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+++ b/sysdeps/i386/fpu/s_floor.S
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+/*
+ * Written by J.T. Conklin <jtc@netbsd.org>.
+ * Public domain.
+ */
+
+#include <machine/asm.h>
+
+RCSID("$NetBSD: s_floor.S,v 1.4 1995/05/09 00:01:59 jtc Exp $")
+
+ENTRY(__floor)
+	fldl	4(%esp)
+	subl	$8,%esp
+
+	fstcw	4(%esp)			/* store fpu control word */
+
+	/* We use here %edx although only the low 1 bits are defined.
+	   But none of the operations should care and they are faster
+	   than the 16 bit operations.  */
+	movl	$0x400,%edx		/* round towards -oo */
+	orl	4(%esp),%edx
+	andl	$0xf7ff,%edx
+	movl	%edx,(%esp)
+	fldcw	(%esp)			/* load modified control word */
+
+	frndint				/* round */
+
+	fldcw	4(%esp)			/* restore original control word */
+
+	addl	$8,%esp
+	ret
+END (__floor)
+weak_alias (__floor, floor)