aboutsummaryrefslogtreecommitdiffstats
path: root/contrib/libs/cxxsupp/builtins/comparesf2.c
blob: 0ed6dd6a4b39d6d73cf8e4a415987475a8224ebc (plain) (blame)
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
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
//===-- lib/comparesf2.c - Single-precision comparisons -----------*- C -*-===// 
// 
//                     The LLVM Compiler Infrastructure 
// 
// This file is dual licensed under the MIT and the University of Illinois Open 
// Source Licenses. See LICENSE.TXT for details. 
// 
//===----------------------------------------------------------------------===// 
// 
// This file implements the following soft-fp_t comparison routines: 
// 
//   __eqsf2   __gesf2   __unordsf2 
//   __lesf2   __gtsf2 
//   __ltsf2 
//   __nesf2 
// 
// The semantics of the routines grouped in each column are identical, so there 
// is a single implementation for each, and wrappers to provide the other names. 
// 
// The main routines behave as follows: 
// 
//   __lesf2(a,b) returns -1 if a < b 
//                         0 if a == b 
//                         1 if a > b 
//                         1 if either a or b is NaN 
// 
//   __gesf2(a,b) returns -1 if a < b 
//                         0 if a == b 
//                         1 if a > b 
//                        -1 if either a or b is NaN 
// 
//   __unordsf2(a,b) returns 0 if both a and b are numbers 
//                           1 if either a or b is NaN 
// 
// Note that __lesf2( ) and __gesf2( ) are identical except in their handling of 
// NaN values. 
// 
//===----------------------------------------------------------------------===// 
 
#define SINGLE_PRECISION 
#include "fp_lib.h" 
 
enum LE_RESULT { 
    LE_LESS      = -1, 
    LE_EQUAL     =  0, 
    LE_GREATER   =  1, 
    LE_UNORDERED =  1 
}; 
 
COMPILER_RT_ABI enum LE_RESULT 
__lesf2(fp_t a, fp_t b) { 
     
    const srep_t aInt = toRep(a); 
    const srep_t bInt = toRep(b); 
    const rep_t aAbs = aInt & absMask; 
    const rep_t bAbs = bInt & absMask; 
     
    // If either a or b is NaN, they are unordered. 
    if (aAbs > infRep || bAbs > infRep) return LE_UNORDERED; 
     
    // If a and b are both zeros, they are equal. 
    if ((aAbs | bAbs) == 0) return LE_EQUAL; 
     
    // If at least one of a and b is positive, we get the same result comparing 
    // a and b as signed integers as we would with a fp_ting-point compare. 
    if ((aInt & bInt) >= 0) { 
        if (aInt < bInt) return LE_LESS; 
        else if (aInt == bInt) return LE_EQUAL; 
        else return LE_GREATER; 
    } 
     
    // Otherwise, both are negative, so we need to flip the sense of the 
    // comparison to get the correct result.  (This assumes a twos- or ones- 
    // complement integer representation; if integers are represented in a 
    // sign-magnitude representation, then this flip is incorrect). 
    else { 
        if (aInt > bInt) return LE_LESS; 
        else if (aInt == bInt) return LE_EQUAL; 
        else return LE_GREATER; 
    } 
} 
 
#if defined(__ELF__) 
// Alias for libgcc compatibility 
FNALIAS(__cmpsf2, __lesf2); 
#endif 
 
enum GE_RESULT { 
    GE_LESS      = -1, 
    GE_EQUAL     =  0, 
    GE_GREATER   =  1, 
    GE_UNORDERED = -1   // Note: different from LE_UNORDERED 
}; 
 
COMPILER_RT_ABI enum GE_RESULT 
__gesf2(fp_t a, fp_t b) { 
     
    const srep_t aInt = toRep(a); 
    const srep_t bInt = toRep(b); 
    const rep_t aAbs = aInt & absMask; 
    const rep_t bAbs = bInt & absMask; 
     
    if (aAbs > infRep || bAbs > infRep) return GE_UNORDERED; 
    if ((aAbs | bAbs) == 0) return GE_EQUAL; 
    if ((aInt & bInt) >= 0) { 
        if (aInt < bInt) return GE_LESS; 
        else if (aInt == bInt) return GE_EQUAL; 
        else return GE_GREATER; 
    } else { 
        if (aInt > bInt) return GE_LESS; 
        else if (aInt == bInt) return GE_EQUAL; 
        else return GE_GREATER; 
    } 
} 
 
ARM_EABI_FNALIAS(fcmpun, unordsf2) 
 
COMPILER_RT_ABI int 
__unordsf2(fp_t a, fp_t b) { 
    const rep_t aAbs = toRep(a) & absMask; 
    const rep_t bAbs = toRep(b) & absMask; 
    return aAbs > infRep || bAbs > infRep; 
} 
 
// The following are alternative names for the preceding routines. 
 
COMPILER_RT_ABI enum LE_RESULT 
__eqsf2(fp_t a, fp_t b) { 
    return __lesf2(a, b); 
} 
 
COMPILER_RT_ABI enum LE_RESULT 
__ltsf2(fp_t a, fp_t b) { 
    return __lesf2(a, b); 
} 
 
COMPILER_RT_ABI enum LE_RESULT 
__nesf2(fp_t a, fp_t b) { 
    return __lesf2(a, b); 
} 
 
COMPILER_RT_ABI enum GE_RESULT 
__gtsf2(fp_t a, fp_t b) { 
    return __gesf2(a, b); 
}