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1 | .file "significand.s" |
2 | ||
3 | ||
4 | // Copyright (c) 2000 - 2003, Intel Corporation | |
5 | // All rights reserved. | |
6 | // | |
d5efd131 MF |
7 | // |
8 | // Redistribution and use in source and binary forms, with or without | |
9 | // modification, are permitted provided that the following conditions are | |
10 | // met: | |
11 | // | |
12 | // * Redistributions of source code must retain the above copyright | |
13 | // notice, this list of conditions and the following disclaimer. | |
14 | // | |
15 | // * Redistributions in binary form must reproduce the above copyright | |
16 | // notice, this list of conditions and the following disclaimer in the | |
17 | // documentation and/or other materials provided with the distribution. | |
18 | // | |
19 | // * The name of Intel Corporation may not be used to endorse or promote | |
20 | // products derived from this software without specific prior written | |
21 | // permission. | |
22 | ||
0347518d MF |
23 | // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS |
24 | // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT | |
d5efd131 | 25 | // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR |
0347518d | 26 | // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL INTEL OR ITS |
d5efd131 | 27 | // CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, |
0347518d MF |
28 | // EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, |
29 | // PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR | |
30 | // PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY | |
d5efd131 | 31 | // OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY OR TORT (INCLUDING |
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32 | // NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS |
33 | // SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. | |
34 | // | |
d5efd131 | 35 | // Intel Corporation is the author of this code, and requests that all |
0347518d | 36 | // problem reports or change requests be submitted to it directly at |
d5efd131 MF |
37 | // http://www.intel.com/software/products/opensource/libraries/num.htm. |
38 | // | |
39 | // History | |
40 | //============================================================== | |
41 | // 02/02/00 Initial version | |
42 | // 04/04/00 Unwind support added | |
43 | // 05/31/00 Fixed bug when x a double-extended denormal | |
44 | // 05/20/02 Cleaned up namespace and sf0 syntax | |
45 | // 02/10/03 Reordered header: .section, .global, .proc, .align | |
46 | // | |
47 | // API | |
48 | //============================================================== | |
49 | // double significand(double x) | |
50 | // | |
51 | // Overview of operation | |
52 | //============================================================== | |
53 | // If x = sig * 2**n with 1 <= sig < 2 | |
54 | // significand returns sig | |
55 | // | |
0347518d | 56 | // predicate registers used: |
d5efd131 MF |
57 | // p6, p7 |
58 | // | |
0347518d MF |
59 | // floating-point registers used: |
60 | // f8, f9, f10 | |
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61 | |
62 | .section .text | |
63 | GLOBAL_LIBM_ENTRY(significand) | |
64 | ||
65 | // qnan snan inf norm unorm 0 -+ | |
66 | // 1 1 1 0 0 1 11 | |
67 | ||
68 | // f10 gets f8(sign) with f1(exp,significand) | |
69 | { .mfi | |
70 | nop.m 999 | |
0347518d | 71 | fmerge.s f10 = f8,f1 |
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72 | nop.i 999 |
73 | } | |
74 | { .mfi | |
75 | nop.m 999 | |
0347518d | 76 | fnorm.s0 f9 = f8 |
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77 | nop.i 999 ;; |
78 | } | |
79 | ||
80 | // Test for denormal input | |
81 | { .mfi | |
82 | nop.m 999 | |
83 | fclass.m.unc p7,p0 = f8, 0x0b | |
84 | nop.i 999 ;; | |
85 | } | |
86 | ||
87 | // p6 = TRUE ==> x is not (nan,inf,0) | |
88 | // return sign(f8) exp(f1) significand(f8) | |
89 | // else x is (nan,inf,0) | |
90 | // return sign(f8) exp(f8) significand(f8), normalized. | |
91 | { .mfi | |
92 | nop.m 999 | |
0347518d | 93 | fclass.m.unc p0,p6 = f8, 0xe7 |
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94 | nop.i 999 ;; |
95 | } | |
96 | ||
97 | { .mmb | |
98 | nop.m 999 | |
99 | nop.m 999 | |
100 | (p7) br.cond.spnt SIGNIFICAND_DENORM ;; // Branch if x denormal | |
101 | } | |
102 | ||
103 | { .mfi | |
104 | nop.m 999 | |
105 | (p6) fmerge.se f8 = f10,f8 | |
106 | nop.i 999 ;; | |
107 | } | |
108 | ||
109 | { .mfb | |
110 | nop.m 999 | |
0347518d | 111 | fnorm.d.s0 f8 = f8 |
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112 | br.ret.sptk b0 ;; |
113 | } | |
114 | ||
115 | SIGNIFICAND_DENORM: | |
116 | // Here if x denorm | |
117 | { .mfi | |
118 | nop.m 999 | |
119 | fmerge.se f8 = f10,f9 | |
120 | nop.i 999 ;; | |
121 | } | |
122 | ||
123 | // Check if fnorm(x) still denormal, means x double-extended denormal | |
124 | { .mfi | |
125 | nop.m 999 | |
126 | fclass.m.unc p7,p0 = f9, 0x0b | |
127 | nop.i 999 ;; | |
128 | } | |
129 | ||
130 | // This will be the final result unless x double-extended denormal | |
131 | { .mfi | |
132 | nop.m 999 | |
133 | fnorm.d.s0 f8 = f8 | |
134 | nop.i 999 ;; | |
135 | } | |
136 | ||
137 | // If x double-extended denorm, then significand ok, but must merge in | |
138 | // correct signexp | |
139 | { .mfi | |
140 | nop.m 999 | |
141 | (p7) fmerge.se f8 = f10,f8 | |
142 | nop.i 999 ;; | |
143 | } | |
144 | ||
145 | // Final normalization if x double-extended denorm | |
146 | { .mfb | |
147 | nop.m 999 | |
148 | (p7) fnorm.d.s0 f8 = f8 | |
149 | br.ret.sptk b0 ;; | |
150 | } | |
151 | ||
152 | GLOBAL_LIBM_END(significand) |