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
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
|
//===--------------- LLVMContextImpl.cpp - Implementation ------*- C++ -*--===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements LLVMContextImpl, the opaque implementation
// of LLVMContext.
//
//===----------------------------------------------------------------------===//
#include "LLVMContextImpl.h"
#include "llvm/Constants.h"
#include "llvm/DerivedTypes.h"
#include "llvm/LLVMContext.h"
#include "llvm/MDNode.h"
using namespace llvm;
static char getValType(ConstantAggregateZero *CPZ) { return 0; }
static std::vector<Constant*> getValType(ConstantArray *CA) {
std::vector<Constant*> Elements;
Elements.reserve(CA->getNumOperands());
for (unsigned i = 0, e = CA->getNumOperands(); i != e; ++i)
Elements.push_back(cast<Constant>(CA->getOperand(i)));
return Elements;
}
static std::vector<Constant*> getValType(ConstantVector *CP) {
std::vector<Constant*> Elements;
Elements.reserve(CP->getNumOperands());
for (unsigned i = 0, e = CP->getNumOperands(); i != e; ++i)
Elements.push_back(CP->getOperand(i));
return Elements;
}
LLVMContextImpl::LLVMContextImpl(LLVMContext &C) :
Context(C), TheTrueVal(0), TheFalseVal(0) { }
MDString *LLVMContextImpl::getMDString(const char *StrBegin,
unsigned StrLength) {
sys::SmartScopedWriter<true> Writer(ConstantsLock);
StringMapEntry<MDString *> &Entry =
MDStringCache.GetOrCreateValue(StringRef(StrBegin, StrLength));
MDString *&S = Entry.getValue();
if (!S) S = new MDString(Entry.getKeyData(),
Entry.getKeyLength());
return S;
}
MDNode *LLVMContextImpl::getMDNode(Value*const* Vals, unsigned NumVals) {
FoldingSetNodeID ID;
for (unsigned i = 0; i != NumVals; ++i)
ID.AddPointer(Vals[i]);
ConstantsLock.reader_acquire();
void *InsertPoint;
MDNode *N = MDNodeSet.FindNodeOrInsertPos(ID, InsertPoint);
ConstantsLock.reader_release();
if (!N) {
sys::SmartScopedWriter<true> Writer(ConstantsLock);
N = MDNodeSet.FindNodeOrInsertPos(ID, InsertPoint);
if (!N) {
// InsertPoint will have been set by the FindNodeOrInsertPos call.
N = new MDNode(Vals, NumVals);
MDNodeSet.InsertNode(N, InsertPoint);
}
}
return N;
}
ConstantAggregateZero*
LLVMContextImpl::getConstantAggregateZero(const Type *Ty) {
assert((isa<StructType>(Ty) || isa<ArrayType>(Ty) || isa<VectorType>(Ty)) &&
"Cannot create an aggregate zero of non-aggregate type!");
// Implicitly locked.
return AggZeroConstants.getOrCreate(Ty, 0);
}
Constant *LLVMContextImpl::getConstantArray(const ArrayType *Ty,
const std::vector<Constant*> &V) {
// If this is an all-zero array, return a ConstantAggregateZero object
if (!V.empty()) {
Constant *C = V[0];
if (!C->isNullValue()) {
// Implicitly locked.
return ArrayConstants.getOrCreate(Ty, V);
}
for (unsigned i = 1, e = V.size(); i != e; ++i)
if (V[i] != C) {
// Implicitly locked.
return ArrayConstants.getOrCreate(Ty, V);
}
}
return Context.getConstantAggregateZero(Ty);
}
Constant *LLVMContextImpl::getConstantVector(const VectorType *Ty,
const std::vector<Constant*> &V) {
assert(!V.empty() && "Vectors can't be empty");
// If this is an all-undef or alll-zero vector, return a
// ConstantAggregateZero or UndefValue.
Constant *C = V[0];
bool isZero = C->isNullValue();
bool isUndef = isa<UndefValue>(C);
if (isZero || isUndef) {
for (unsigned i = 1, e = V.size(); i != e; ++i)
if (V[i] != C) {
isZero = isUndef = false;
break;
}
}
if (isZero)
return Context.getConstantAggregateZero(Ty);
if (isUndef)
return Context.getUndef(Ty);
// Implicitly locked.
return VectorConstants.getOrCreate(Ty, V);
}
// *** erase methods ***
void LLVMContextImpl::erase(MDString *M) {
sys::SmartScopedWriter<true> Writer(ConstantsLock);
MDStringCache.erase(MDStringCache.find(M->getString()));
}
void LLVMContextImpl::erase(MDNode *M) {
sys::SmartScopedWriter<true> Writer(ConstantsLock);
MDNodeSet.RemoveNode(M);
}
void LLVMContextImpl::erase(ConstantAggregateZero *Z) {
AggZeroConstants.remove(Z);
}
void LLVMContextImpl::erase(ConstantArray *C) {
ArrayConstants.remove(C);
}
void LLVMContextImpl::erase(ConstantVector *V) {
VectorConstants.remove(V);
}
// *** RAUW helpers ***
Constant *LLVMContextImpl::replaceUsesOfWithOnConstant(ConstantArray *CA,
Value *From, Value *To, Use *U) {
assert(isa<Constant>(To) && "Cannot make Constant refer to non-constant!");
Constant *ToC = cast<Constant>(To);
std::pair<ArrayConstantsTy::MapKey, Constant*> Lookup;
Lookup.first.first = CA->getType();
Lookup.second = CA;
std::vector<Constant*> &Values = Lookup.first.second;
Values.reserve(CA->getNumOperands()); // Build replacement array.
// Fill values with the modified operands of the constant array. Also,
// compute whether this turns into an all-zeros array.
bool isAllZeros = false;
unsigned NumUpdated = 0;
if (!ToC->isNullValue()) {
for (Use *O = CA->OperandList, *E = CA->OperandList + CA->getNumOperands();
O != E; ++O) {
Constant *Val = cast<Constant>(O->get());
if (Val == From) {
Val = ToC;
++NumUpdated;
}
Values.push_back(Val);
}
} else {
isAllZeros = true;
for (Use *O = CA->OperandList, *E = CA->OperandList + CA->getNumOperands();
O != E; ++O) {
Constant *Val = cast<Constant>(O->get());
if (Val == From) {
Val = ToC;
++NumUpdated;
}
Values.push_back(Val);
if (isAllZeros) isAllZeros = Val->isNullValue();
}
}
Constant *Replacement = 0;
if (isAllZeros) {
Replacement = Context.getConstantAggregateZero(CA->getType());
} else {
// Check to see if we have this array type already.
sys::SmartScopedWriter<true> Writer(ConstantsLock);
bool Exists;
ArrayConstantsTy::MapTy::iterator I =
ArrayConstants.InsertOrGetItem(Lookup, Exists);
if (Exists) {
Replacement = I->second;
} else {
// Okay, the new shape doesn't exist in the system yet. Instead of
// creating a new constant array, inserting it, replaceallusesof'ing the
// old with the new, then deleting the old... just update the current one
// in place!
ArrayConstants.MoveConstantToNewSlot(CA, I);
// Update to the new value. Optimize for the case when we have a single
// operand that we're changing, but handle bulk updates efficiently.
if (NumUpdated == 1) {
unsigned OperandToUpdate = U - CA->OperandList;
assert(CA->getOperand(OperandToUpdate) == From &&
"ReplaceAllUsesWith broken!");
CA->setOperand(OperandToUpdate, ToC);
} else {
for (unsigned i = 0, e = CA->getNumOperands(); i != e; ++i)
if (CA->getOperand(i) == From)
CA->setOperand(i, ToC);
}
return 0;
}
}
return Replacement;
}
|