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
196
197
198
199
200
201
202
203
204
205
206
207
208
209
|
//===--- Pointer.cpp - Types for the constexpr VM ---------------*- C++ -*-===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
#include "Pointer.h"
#include "Function.h"
#include "InterpBlock.h"
#include "PrimType.h"
using namespace clang;
using namespace clang::interp;
Pointer::Pointer(Block *Pointee) : Pointer(Pointee, 0, 0) {}
Pointer::Pointer(Block *Pointee, unsigned BaseAndOffset)
: Pointer(Pointee, BaseAndOffset, BaseAndOffset) {}
Pointer::Pointer(const Pointer &P) : Pointer(P.Pointee, P.Base, P.Offset) {}
Pointer::Pointer(Pointer &&P)
: Pointee(P.Pointee), Base(P.Base), Offset(P.Offset) {
if (Pointee)
Pointee->movePointer(&P, this);
}
Pointer::Pointer(Block *Pointee, unsigned Base, unsigned Offset)
: Pointee(Pointee), Base(Base), Offset(Offset) {
assert((Base == RootPtrMark || Base % alignof(void *) == 0) && "wrong base");
if (Pointee)
Pointee->addPointer(this);
}
Pointer::~Pointer() {
if (Pointee) {
Pointee->removePointer(this);
Pointee->cleanup();
}
}
void Pointer::operator=(const Pointer &P) {
Block *Old = Pointee;
if (Pointee)
Pointee->removePointer(this);
Offset = P.Offset;
Base = P.Base;
Pointee = P.Pointee;
if (Pointee)
Pointee->addPointer(this);
if (Old)
Old->cleanup();
}
void Pointer::operator=(Pointer &&P) {
Block *Old = Pointee;
if (Pointee)
Pointee->removePointer(this);
Offset = P.Offset;
Base = P.Base;
Pointee = P.Pointee;
if (Pointee)
Pointee->movePointer(&P, this);
if (Old)
Old->cleanup();
}
APValue Pointer::toAPValue() const {
APValue::LValueBase Base;
llvm::SmallVector<APValue::LValuePathEntry, 5> Path;
CharUnits Offset;
bool IsNullPtr;
bool IsOnePastEnd;
if (isZero()) {
Base = static_cast<const Expr *>(nullptr);
IsNullPtr = true;
IsOnePastEnd = false;
Offset = CharUnits::Zero();
} else {
// Build the lvalue base from the block.
Descriptor *Desc = getDeclDesc();
if (auto *VD = Desc->asValueDecl())
Base = VD;
else if (auto *E = Desc->asExpr())
Base = E;
else
llvm_unreachable("Invalid allocation type");
// Not a null pointer.
IsNullPtr = false;
if (isUnknownSizeArray()) {
IsOnePastEnd = false;
Offset = CharUnits::Zero();
} else {
// TODO: compute the offset into the object.
Offset = CharUnits::Zero();
// Build the path into the object.
Pointer Ptr = *this;
while (Ptr.isField() || Ptr.isArrayElement()) {
if (Ptr.isArrayElement()) {
Path.push_back(APValue::LValuePathEntry::ArrayIndex(Ptr.getIndex()));
Ptr = Ptr.getArray();
} else {
// TODO: figure out if base is virtual
bool IsVirtual = false;
// Create a path entry for the field.
Descriptor *Desc = Ptr.getFieldDesc();
if (auto *BaseOrMember = Desc->asDecl()) {
Path.push_back(APValue::LValuePathEntry({BaseOrMember, IsVirtual}));
Ptr = Ptr.getBase();
continue;
}
llvm_unreachable("Invalid field type");
}
}
IsOnePastEnd = isOnePastEnd();
}
}
// We assemble the LValuePath starting from the innermost pointer to the
// outermost one. SO in a.b.c, the first element in Path will refer to
// the field 'c', while later code expects it to refer to 'a'.
// Just invert the order of the elements.
std::reverse(Path.begin(), Path.end());
return APValue(Base, Offset, Path, IsOnePastEnd, IsNullPtr);
}
bool Pointer::isInitialized() const {
assert(Pointee && "Cannot check if null pointer was initialized");
Descriptor *Desc = getFieldDesc();
assert(Desc);
if (Desc->isPrimitiveArray()) {
if (isStatic() && Base == 0)
return true;
// Primitive array field are stored in a bitset.
InitMap *Map = getInitMap();
if (!Map)
return false;
if (Map == (InitMap *)-1)
return true;
return Map->isInitialized(getIndex());
} else {
// Field has its bit in an inline descriptor.
return Base == 0 || getInlineDesc()->IsInitialized;
}
}
void Pointer::initialize() const {
assert(Pointee && "Cannot initialize null pointer");
Descriptor *Desc = getFieldDesc();
assert(Desc);
if (Desc->isArray()) {
if (Desc->isPrimitiveArray()) {
// Primitive global arrays don't have an initmap.
if (isStatic() && Base == 0)
return;
// Primitive array initializer.
InitMap *&Map = getInitMap();
if (Map == (InitMap *)-1)
return;
if (Map == nullptr)
Map = InitMap::allocate(Desc->getNumElems());
if (Map->initialize(getIndex())) {
free(Map);
Map = (InitMap *)-1;
}
}
} else {
// Field has its bit in an inline descriptor.
assert(Base != 0 && "Only composite fields can be initialised");
getInlineDesc()->IsInitialized = true;
}
}
void Pointer::activate() const {
// Field has its bit in an inline descriptor.
assert(Base != 0 && "Only composite fields can be initialised");
getInlineDesc()->IsActive = true;
}
void Pointer::deactivate() const {
// TODO: this only appears in constructors, so nothing to deactivate.
}
bool Pointer::hasSameBase(const Pointer &A, const Pointer &B) {
return A.Pointee == B.Pointee;
}
bool Pointer::hasSameArray(const Pointer &A, const Pointer &B) {
return hasSameBase(A, B) && A.Base == B.Base && A.getFieldDesc()->IsArray;
}
|
