summaryrefslogtreecommitdiff
path: root/arch/mips/math-emu/dp_fint.c
blob: 996b15ba07a073d314b05275d3785203ce96d3f8 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
// SPDX-License-Identifier: GPL-2.0-only
/* IEEE754 floating point arithmetic
 * double precision: common utilities
 */
/*
 * MIPS floating point support
 * Copyright (C) 1994-2000 Algorithmics Ltd.
 */

#include "ieee754dp.h"

union ieee754dp ieee754dp_fint(int x)
{
	u64 xm;
	int xe;
	int xs;

	ieee754_clearcx();

	if (x == 0)
		return ieee754dp_zero(0);
	if (x == 1 || x == -1)
		return ieee754dp_one(x < 0);
	if (x == 10 || x == -10)
		return ieee754dp_ten(x < 0);

	xs = (x < 0);
	if (xs) {
		if (x == (1 << 31))
			xm = ((unsigned) 1 << 31);	/* max neg can't be safely negated */
		else
			xm = -x;
	} else {
		xm = x;
	}

	/* normalize - result can never be inexact or overflow */
	xe = DP_FBITS;
	while ((xm >> DP_FBITS) == 0) {
		xm <<= 1;
		xe--;
	}
	return builddp(xs, xe + DP_EBIAS, xm & ~DP_HIDDEN_BIT);
}