xref: /csrg-svn/lib/libc/sparc/gen/fixunsdfsi.s (revision 54386)
1*54386Storek/*
2*54386Storek * Copyright (c) 1992 The Regents of the University of California.
3*54386Storek * All rights reserved.
4*54386Storek *
5*54386Storek * This software was developed by the Computer Systems Engineering group
6*54386Storek * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and
7*54386Storek * contributed to Berkeley.
8*54386Storek *
9*54386Storek * %sccs.include.redist.c%
10*54386Storek *
11*54386Storek * from: $Header: fixunsdfsi.s,v 1.3 91/10/08 00:03:15 torek Exp $
12*54386Storek */
13*54386Storek
14*54386Storek#if defined(LIBC_SCCS) && !defined(lint)
15*54386Storek	.asciz "@(#)fixunsdfsi.s	5.1 (Berkeley) 06/25/92"
16*54386Storek#endif /* LIBC_SCCS and not lint */
17*54386Storek
18*54386Storek/*
19*54386Storek * Convert double to unsigned integer (for gcc).
20*54386Storek *
21*54386Storek * I have made the output for NaN agree with the Sun compiler, not
22*54386Storek * that it really matters, by using `fbul,a'.
23*54386Storek */
24*54386Storek
25*54386Storek#include "DEFS.h"
26*54386Storek
27*54386Storek	.align	8
28*54386StorekLbig:
29*54386Storek	.word	0x41e00000		! .double 0r2147483648.0e+00
30*54386Storek	.word	0			! (who me, not trust the assembler?)
31*54386Storek
32*54386StorekENTRY(__fixunsdfsi)
33*54386Storek	sub	%sp, 8, %sp
34*54386Storek	std	%o0, [%sp + 64]		! get argument into fpu reg
35*54386Storek	ldd	[%sp + 64], %f0
36*54386Storek	sethi	%hi(Lbig), %g1
37*54386Storek	ldd	[%g1 + %lo(Lbig)], %f2
38*54386Storek	fcmped	%f0, %f2		! d < 2^31, or NaN, or -Inf?
39*54386Storek	nop				! (fpop2 delay)
40*54386Storek	fbul,a	1f			! if so, use fdtoi to convert to int
41*54386Storek	fdtoi	%f0, %f0		!        (this includes negatives!)
42*54386Storek
43*54386Storek	! d does not fit in an int, so subtract 2^31, convert,
44*54386Storek	! and add 2^31 again (sigh).  Just hope the intermediate
45*54386Storek	! fits (if not, the result is undefined anyway).
46*54386Storek
47*54386Storek	fsubd	%f0, %f2, %f0		! d -= 2^31
48*54386Storek	fdtoi	%f0, %f0		! convert to int
49*54386Storek	st	%f0, [%sp + 64]		! move into return reg
50*54386Storek	ld	[%sp + 64], %o0
51*54386Storek	sethi	%hi(0x80000000), %o1
52*54386Storek	add	%o0, %o1, %o0		! add 2^31
53*54386Storek	retl
54*54386Storek	add	%sp, 8, %sp
55*54386Storek
56*54386Storek1:
57*54386Storek	st	%f0, [%sp + 64]		! return result
58*54386Storek	ld	[%sp + 64], %o0
59*54386Storek	retl
60*54386Storek	add	%sp, 8, %sp
61