diff options
Diffstat (limited to 'arch/mips/math-emu/sp_add.c')
-rw-r--r-- | arch/mips/math-emu/sp_add.c | 53 |
1 files changed, 28 insertions, 25 deletions
diff --git a/arch/mips/math-emu/sp_add.c b/arch/mips/math-emu/sp_add.c index db4d89beada6..a0bc95cea1cc 100644 --- a/arch/mips/math-emu/sp_add.c +++ b/arch/mips/math-emu/sp_add.c | |||
@@ -5,8 +5,6 @@ | |||
5 | * MIPS floating point support | 5 | * MIPS floating point support |
6 | * Copyright (C) 1994-2000 Algorithmics Ltd. | 6 | * Copyright (C) 1994-2000 Algorithmics Ltd. |
7 | * | 7 | * |
8 | * ######################################################################## | ||
9 | * | ||
10 | * This program is free software; you can distribute it and/or modify it | 8 | * This program is free software; you can distribute it and/or modify it |
11 | * under the terms of the GNU General Public License (Version 2) as | 9 | * under the terms of the GNU General Public License (Version 2) as |
12 | * published by the Free Software Foundation. | 10 | * published by the Free Software Foundation. |
@@ -18,16 +16,15 @@ | |||
18 | * | 16 | * |
19 | * You should have received a copy of the GNU General Public License along | 17 | * You should have received a copy of the GNU General Public License along |
20 | * with this program; if not, write to the Free Software Foundation, Inc., | 18 | * with this program; if not, write to the Free Software Foundation, Inc., |
21 | * 59 Temple Place - Suite 330, Boston MA 02111-1307, USA. | 19 | * 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
22 | * | ||
23 | * ######################################################################## | ||
24 | */ | 20 | */ |
25 | 21 | ||
26 | |||
27 | #include "ieee754sp.h" | 22 | #include "ieee754sp.h" |
28 | 23 | ||
29 | union ieee754sp ieee754sp_add(union ieee754sp x, union ieee754sp y) | 24 | union ieee754sp ieee754sp_add(union ieee754sp x, union ieee754sp y) |
30 | { | 25 | { |
26 | int s; | ||
27 | |||
31 | COMPXSP; | 28 | COMPXSP; |
32 | COMPYSP; | 29 | COMPYSP; |
33 | 30 | ||
@@ -68,9 +65,9 @@ union ieee754sp ieee754sp_add(union ieee754sp x, union ieee754sp y) | |||
68 | return x; | 65 | return x; |
69 | 66 | ||
70 | 67 | ||
71 | /* Infinity handling | 68 | /* |
72 | */ | 69 | * Infinity handling |
73 | 70 | */ | |
74 | case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_INF): | 71 | case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_INF): |
75 | if (xs == ys) | 72 | if (xs == ys) |
76 | return x; | 73 | return x; |
@@ -87,15 +84,14 @@ union ieee754sp ieee754sp_add(union ieee754sp x, union ieee754sp y) | |||
87 | case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_DNORM): | 84 | case CLPAIR(IEEE754_CLASS_INF, IEEE754_CLASS_DNORM): |
88 | return x; | 85 | return x; |
89 | 86 | ||
90 | /* Zero handling | 87 | /* |
91 | */ | 88 | * Zero handling |
92 | 89 | */ | |
93 | case CLPAIR(IEEE754_CLASS_ZERO, IEEE754_CLASS_ZERO): | 90 | case CLPAIR(IEEE754_CLASS_ZERO, IEEE754_CLASS_ZERO): |
94 | if (xs == ys) | 91 | if (xs == ys) |
95 | return x; | 92 | return x; |
96 | else | 93 | else |
97 | return ieee754sp_zero(ieee754_csr.rm == | 94 | return ieee754sp_zero(ieee754_csr.rm == IEEE754_RD); |
98 | IEEE754_RD); | ||
99 | 95 | ||
100 | case CLPAIR(IEEE754_CLASS_NORM, IEEE754_CLASS_ZERO): | 96 | case CLPAIR(IEEE754_CLASS_NORM, IEEE754_CLASS_ZERO): |
101 | case CLPAIR(IEEE754_CLASS_DNORM, IEEE754_CLASS_ZERO): | 97 | case CLPAIR(IEEE754_CLASS_DNORM, IEEE754_CLASS_ZERO): |
@@ -108,6 +104,8 @@ union ieee754sp ieee754sp_add(union ieee754sp x, union ieee754sp y) | |||
108 | case CLPAIR(IEEE754_CLASS_DNORM, IEEE754_CLASS_DNORM): | 104 | case CLPAIR(IEEE754_CLASS_DNORM, IEEE754_CLASS_DNORM): |
109 | SPDNORMX; | 105 | SPDNORMX; |
110 | 106 | ||
107 | /* FALL THROUGH */ | ||
108 | |||
111 | case CLPAIR(IEEE754_CLASS_NORM, IEEE754_CLASS_DNORM): | 109 | case CLPAIR(IEEE754_CLASS_NORM, IEEE754_CLASS_DNORM): |
112 | SPDNORMY; | 110 | SPDNORMY; |
113 | break; | 111 | break; |
@@ -122,27 +120,32 @@ union ieee754sp ieee754sp_add(union ieee754sp x, union ieee754sp y) | |||
122 | assert(xm & SP_HIDDEN_BIT); | 120 | assert(xm & SP_HIDDEN_BIT); |
123 | assert(ym & SP_HIDDEN_BIT); | 121 | assert(ym & SP_HIDDEN_BIT); |
124 | 122 | ||
125 | /* provide guard,round and stick bit space */ | 123 | /* |
124 | * Provide guard, round and stick bit space. | ||
125 | */ | ||
126 | xm <<= 3; | 126 | xm <<= 3; |
127 | ym <<= 3; | 127 | ym <<= 3; |
128 | 128 | ||
129 | if (xe > ye) { | 129 | if (xe > ye) { |
130 | /* have to shift y fraction right to align | 130 | /* |
131 | * Have to shift y fraction right to align. | ||
131 | */ | 132 | */ |
132 | int s = xe - ye; | 133 | s = xe - ye; |
133 | SPXSRSYn(s); | 134 | SPXSRSYn(s); |
134 | } else if (ye > xe) { | 135 | } else if (ye > xe) { |
135 | /* have to shift x fraction right to align | 136 | /* |
137 | * Have to shift x fraction right to align. | ||
136 | */ | 138 | */ |
137 | int s = ye - xe; | 139 | s = ye - xe; |
138 | SPXSRSXn(s); | 140 | SPXSRSXn(s); |
139 | } | 141 | } |
140 | assert(xe == ye); | 142 | assert(xe == ye); |
141 | assert(xe <= SP_EMAX); | 143 | assert(xe <= SP_EMAX); |
142 | 144 | ||
143 | if (xs == ys) { | 145 | if (xs == ys) { |
144 | /* generate 28 bit result of adding two 27 bit numbers | 146 | /* |
145 | * leaving result in xm,xs,xe | 147 | * Generate 28 bit result of adding two 27 bit numbers |
148 | * leaving result in xm, xs and xe. | ||
146 | */ | 149 | */ |
147 | xm = xm + ym; | 150 | xm = xm + ym; |
148 | xe = xe; | 151 | xe = xe; |
@@ -162,15 +165,15 @@ union ieee754sp ieee754sp_add(union ieee754sp x, union ieee754sp y) | |||
162 | xs = ys; | 165 | xs = ys; |
163 | } | 166 | } |
164 | if (xm == 0) | 167 | if (xm == 0) |
165 | return ieee754sp_zero(ieee754_csr.rm == | 168 | return ieee754sp_zero(ieee754_csr.rm == IEEE754_RD); |
166 | IEEE754_RD); | ||
167 | 169 | ||
168 | /* normalize in extended single precision */ | 170 | /* |
171 | * Normalize in extended single precision | ||
172 | */ | ||
169 | while ((xm >> (SP_FBITS + 3)) == 0) { | 173 | while ((xm >> (SP_FBITS + 3)) == 0) { |
170 | xm <<= 1; | 174 | xm <<= 1; |
171 | xe--; | 175 | xe--; |
172 | } | 176 | } |
173 | |||
174 | } | 177 | } |
175 | 178 | ||
176 | return ieee754sp_format(xs, xe, xm); | 179 | return ieee754sp_format(xs, xe, xm); |