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
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
|
//===-- llvm/Support/ConstantRange.h - Represent a range --------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// Represent a range of possible values that may occur when the program is run
// for an integral value. This keeps track of a lower and upper bound for the
// constant, which MAY wrap around the end of the numeric range. To do this, it
// keeps track of a [lower, upper) bound, which specifies an interval just like
// STL iterators. When used with boolean values, the following are important
// ranges: :
//
// [F, F) = {} = Empty set
// [T, F) = {T}
// [F, T) = {F}
// [T, T) = {F, T} = Full set
//
// The other integral ranges use min/max values for special range values. For
// example, for 8-bit types, it uses:
// [0, 0) = {} = Empty set
// [255, 255) = {0..255} = Full Set
//
// Note that ConstantRange always keeps unsigned values.
//===----------------------------------------------------------------------===//
#ifndef LLVM_SUPPORT_CONSTANT_RANGE_H
#define LLVM_SUPPORT_CONSTANT_RANGE_H
#include "llvm/ADT/APInt.h"
#include "llvm/Support/DataTypes.h"
namespace llvm {
class ConstantRange {
APInt Lower, Upper;
static ConstantRange intersect1Wrapped(const ConstantRange &LHS,
const ConstantRange &RHS);
public:
/// Initialize a full (the default) or empty set for the specified bit width.
///
explicit ConstantRange(uint32_t BitWidth, bool isFullSet = true);
/// Initialize a range to hold the single specified value.
///
ConstantRange(const APInt &Value);
/// @brief Initialize a range of values explicitly. This will assert out if
/// Lower==Upper and Lower != Min or Max value for its type. It will also
/// assert out if the two APInt's are not the same bit width.
ConstantRange(const APInt& Lower, const APInt& Upper);
/// getLower - Return the lower value for this range...
///
const APInt &getLower() const { return Lower; }
/// getUpper - Return the upper value for this range...
///
const APInt &getUpper() const { return Upper; }
/// getBitWidth - get the bit width of this ConstantRange
///
uint32_t getBitWidth() const { return Lower.getBitWidth(); }
/// isFullSet - Return true if this set contains all of the elements possible
/// for this data-type
///
bool isFullSet() const;
/// isEmptySet - Return true if this set contains no members.
///
bool isEmptySet() const;
/// isWrappedSet - Return true if this set wraps around the top of the range,
/// for example: [100, 8)
///
bool isWrappedSet() const;
/// contains - Return true if the specified value is in the set.
///
bool contains(const APInt &Val) const;
/// getSingleElement - If this set contains a single element, return it,
/// otherwise return null.
///
const APInt *getSingleElement() const {
if (Upper == Lower + 1)
return &Lower;
return 0;
}
/// isSingleElement - Return true if this set contains exactly one member.
///
bool isSingleElement() const { return getSingleElement() != 0; }
/// getSetSize - Return the number of elements in this set.
///
APInt getSetSize() const;
/// getUnsignedMax - Return the largest unsigned value contained in the
/// ConstantRange.
///
APInt getUnsignedMax() const;
/// getUnsignedMin - Return the smallest unsigned value contained in the
/// ConstantRange.
///
APInt getUnsignedMin() const;
/// getSignedMax - Return the largest signed value contained in the
/// ConstantRange.
///
APInt getSignedMax() const;
/// getSignedMin - Return the smallest signed value contained in the
/// ConstantRange.
///
APInt getSignedMin() const;
/// operator== - Return true if this range is equal to another range.
///
bool operator==(const ConstantRange &CR) const {
return Lower == CR.Lower && Upper == CR.Upper;
}
bool operator!=(const ConstantRange &CR) const {
return !operator==(CR);
}
/// subtract - Subtract the specified constant from the endpoints of this
/// constant range.
ConstantRange subtract(const APInt &CI) const;
/// intersectWith - Return the range that results from the intersection of
/// this range with another range. The resultant range is pruned as much as
/// possible, but there may be cases where elements are included that are in
/// one of the sets but not the other. For example: [100, 8) intersect [3,
/// 120) yields [3, 120)
///
ConstantRange intersectWith(const ConstantRange &CR) const;
/// maximalIntersectWith - Return the range that results from the intersection
/// of this range with another range. The resultant range is guaranteed to
/// include all elements contained in both input ranges, and to have the
/// smallest possible set size that does so. Because there may be two
/// intersections with the same set size, A.maximalIntersectWith(B) might not
/// be equal to B.maximalIntersectWith(A).
///
ConstantRange maximalIntersectWith(const ConstantRange &CR) const;
/// unionWith - Return the range that results from the union of this range
/// with another range. The resultant range is guaranteed to include the
/// elements of both sets, but may contain more. For example, [3, 9) union
/// [12,15) is [3, 15), which includes 9, 10, and 11, which were not included
/// in either set before.
///
ConstantRange unionWith(const ConstantRange &CR) const;
/// zeroExtend - Return a new range in the specified integer type, which must
/// be strictly larger than the current type. The returned range will
/// correspond to the possible range of values if the source range had been
/// zero extended to BitWidth.
ConstantRange zeroExtend(uint32_t BitWidth) const;
/// signExtend - Return a new range in the specified integer type, which must
/// be strictly larger than the current type. The returned range will
/// correspond to the possible range of values if the source range had been
/// sign extended to BitWidth.
ConstantRange signExtend(uint32_t BitWidth) const;
/// truncate - Return a new range in the specified integer type, which must be
/// strictly smaller than the current type. The returned range will
/// correspond to the possible range of values if the source range had been
/// truncated to the specified type.
ConstantRange truncate(uint32_t BitWidth) const;
/// print - Print out the bounds to a stream...
///
void print(raw_ostream &OS) const;
/// dump - Allow printing from a debugger easily...
///
void dump() const;
};
inline raw_ostream &operator<<(raw_ostream &OS, const ConstantRange &CR) {
CR.print(OS);
return OS;
}
} // End llvm namespace
#endif
|
