diff options
Diffstat (limited to 'arch/mips/math-emu/dp_tlong.c')
-rw-r--r-- | arch/mips/math-emu/dp_tlong.c | 127 |
1 files changed, 127 insertions, 0 deletions
diff --git a/arch/mips/math-emu/dp_tlong.c b/arch/mips/math-emu/dp_tlong.c new file mode 100644 index 000000000000..d71113e07164 --- /dev/null +++ b/arch/mips/math-emu/dp_tlong.c | |||
@@ -0,0 +1,127 @@ | |||
1 | /* IEEE754 floating point arithmetic | ||
2 | * double precision: common utilities | ||
3 | */ | ||
4 | /* | ||
5 | * MIPS floating point support | ||
6 | * Copyright (C) 1994-2000 Algorithmics Ltd. | ||
7 | * http://www.algor.co.uk | ||
8 | * | ||
9 | * ######################################################################## | ||
10 | * | ||
11 | * This program is free software; you can distribute it and/or modify it | ||
12 | * under the terms of the GNU General Public License (Version 2) as | ||
13 | * published by the Free Software Foundation. | ||
14 | * | ||
15 | * This program is distributed in the hope it will be useful, but WITHOUT | ||
16 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or | ||
17 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License | ||
18 | * for more details. | ||
19 | * | ||
20 | * You should have received a copy of the GNU General Public License along | ||
21 | * with this program; if not, write to the Free Software Foundation, Inc., | ||
22 | * 59 Temple Place - Suite 330, Boston MA 02111-1307, USA. | ||
23 | * | ||
24 | * ######################################################################## | ||
25 | */ | ||
26 | |||
27 | |||
28 | #include "ieee754dp.h" | ||
29 | |||
30 | s64 ieee754dp_tlong(ieee754dp x) | ||
31 | { | ||
32 | COMPXDP; | ||
33 | |||
34 | CLEARCX; | ||
35 | |||
36 | EXPLODEXDP; | ||
37 | FLUSHXDP; | ||
38 | |||
39 | switch (xc) { | ||
40 | case IEEE754_CLASS_SNAN: | ||
41 | case IEEE754_CLASS_QNAN: | ||
42 | case IEEE754_CLASS_INF: | ||
43 | SETCX(IEEE754_INVALID_OPERATION); | ||
44 | return ieee754di_xcpt(ieee754di_indef(), "dp_tlong", x); | ||
45 | case IEEE754_CLASS_ZERO: | ||
46 | return 0; | ||
47 | case IEEE754_CLASS_DNORM: | ||
48 | case IEEE754_CLASS_NORM: | ||
49 | break; | ||
50 | } | ||
51 | if (xe >= 63) { | ||
52 | /* look for valid corner case */ | ||
53 | if (xe == 63 && xs && xm == DP_HIDDEN_BIT) | ||
54 | return -0x8000000000000000LL; | ||
55 | /* Set invalid. We will only use overflow for floating | ||
56 | point overflow */ | ||
57 | SETCX(IEEE754_INVALID_OPERATION); | ||
58 | return ieee754di_xcpt(ieee754di_indef(), "dp_tlong", x); | ||
59 | } | ||
60 | /* oh gawd */ | ||
61 | if (xe > DP_MBITS) { | ||
62 | xm <<= xe - DP_MBITS; | ||
63 | } else if (xe < DP_MBITS) { | ||
64 | u64 residue; | ||
65 | int round; | ||
66 | int sticky; | ||
67 | int odd; | ||
68 | |||
69 | if (xe < -1) { | ||
70 | residue = xm; | ||
71 | round = 0; | ||
72 | sticky = residue != 0; | ||
73 | xm = 0; | ||
74 | } | ||
75 | else { | ||
76 | /* Shifting a u64 64 times does not work, | ||
77 | * so we do it in two steps. Be aware that xe | ||
78 | * may be -1 */ | ||
79 | residue = xm << (xe + 1); | ||
80 | residue <<= 63 - DP_MBITS; | ||
81 | round = (residue >> 63) != 0; | ||
82 | sticky = (residue << 1) != 0; | ||
83 | xm >>= DP_MBITS - xe; | ||
84 | } | ||
85 | odd = (xm & 0x1) != 0x0; | ||
86 | switch (ieee754_csr.rm) { | ||
87 | case IEEE754_RN: | ||
88 | if (round && (sticky || odd)) | ||
89 | xm++; | ||
90 | break; | ||
91 | case IEEE754_RZ: | ||
92 | break; | ||
93 | case IEEE754_RU: /* toward +Infinity */ | ||
94 | if ((round || sticky) && !xs) | ||
95 | xm++; | ||
96 | break; | ||
97 | case IEEE754_RD: /* toward -Infinity */ | ||
98 | if ((round || sticky) && xs) | ||
99 | xm++; | ||
100 | break; | ||
101 | } | ||
102 | if ((xm >> 63) != 0) { | ||
103 | /* This can happen after rounding */ | ||
104 | SETCX(IEEE754_INVALID_OPERATION); | ||
105 | return ieee754di_xcpt(ieee754di_indef(), "dp_tlong", x); | ||
106 | } | ||
107 | if (round || sticky) | ||
108 | SETCX(IEEE754_INEXACT); | ||
109 | } | ||
110 | if (xs) | ||
111 | return -xm; | ||
112 | else | ||
113 | return xm; | ||
114 | } | ||
115 | |||
116 | |||
117 | u64 ieee754dp_tulong(ieee754dp x) | ||
118 | { | ||
119 | ieee754dp hb = ieee754dp_1e63(); | ||
120 | |||
121 | /* what if x < 0 ?? */ | ||
122 | if (ieee754dp_lt(x, hb)) | ||
123 | return (u64) ieee754dp_tlong(x); | ||
124 | |||
125 | return (u64) ieee754dp_tlong(ieee754dp_sub(x, hb)) | | ||
126 | (1ULL << 63); | ||
127 | } | ||