1 //===- ValueMapper.cpp - Interface shared by lib/Transforms/Utils ---------===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file defines the MapValue function, which is shared by various parts of
11 // the lib/Transforms/Utils library.
13 //===----------------------------------------------------------------------===//
15 #include "llvm/Transforms/Utils/ValueMapper.h"
16 #include "llvm/BasicBlock.h"
17 #include "llvm/Constants.h"
18 #include "llvm/GlobalValue.h"
19 #include "llvm/Instruction.h"
20 #include "llvm/LLVMContext.h"
21 #include "llvm/MDNode.h"
22 #include "llvm/ADT/SmallVector.h"
23 #include "llvm/Support/ErrorHandling.h"
26 Value *llvm::MapValue(const Value *V, ValueMapTy &VM, LLVMContext &Context) {
27 Value *&VMSlot = VM[V];
28 if (VMSlot) return VMSlot; // Does it exist in the map yet?
30 // NOTE: VMSlot can be invalidated by any reference to VM, which can grow the
31 // DenseMap. This includes any recursive calls to MapValue.
33 // Global values do not need to be seeded into the ValueMap if they are using
34 // the identity mapping.
35 if (isa<GlobalValue>(V) || isa<InlineAsm>(V))
36 return VMSlot = const_cast<Value*>(V);
38 if (Constant *C = const_cast<Constant*>(dyn_cast<Constant>(V))) {
39 if (isa<ConstantInt>(C) || isa<ConstantFP>(C) ||
40 isa<ConstantPointerNull>(C) || isa<ConstantAggregateZero>(C) ||
41 isa<UndefValue>(C) || isa<MDString>(C))
42 return VMSlot = C; // Primitive constants map directly
43 else if (ConstantArray *CA = dyn_cast<ConstantArray>(C)) {
44 for (User::op_iterator b = CA->op_begin(), i = b, e = CA->op_end();
46 Value *MV = MapValue(*i, VM, Context);
48 // This array must contain a reference to a global, make a new array
51 std::vector<Constant*> Values;
52 Values.reserve(CA->getNumOperands());
53 for (User::op_iterator j = b; j != i; ++j)
54 Values.push_back(cast<Constant>(*j));
55 Values.push_back(cast<Constant>(MV));
56 for (++i; i != e; ++i)
57 Values.push_back(cast<Constant>(MapValue(*i, VM, Context)));
58 return VM[V] = Context.getConstantArray(CA->getType(), Values);
63 } else if (ConstantStruct *CS = dyn_cast<ConstantStruct>(C)) {
64 for (User::op_iterator b = CS->op_begin(), i = b, e = CS->op_end();
66 Value *MV = MapValue(*i, VM, Context);
68 // This struct must contain a reference to a global, make a new struct
71 std::vector<Constant*> Values;
72 Values.reserve(CS->getNumOperands());
73 for (User::op_iterator j = b; j != i; ++j)
74 Values.push_back(cast<Constant>(*j));
75 Values.push_back(cast<Constant>(MV));
76 for (++i; i != e; ++i)
77 Values.push_back(cast<Constant>(MapValue(*i, VM, Context)));
78 return VM[V] = Context.getConstantStruct(CS->getType(), Values);
83 } else if (ConstantExpr *CE = dyn_cast<ConstantExpr>(C)) {
84 std::vector<Constant*> Ops;
85 for (User::op_iterator i = CE->op_begin(), e = CE->op_end(); i != e; ++i)
86 Ops.push_back(cast<Constant>(MapValue(*i, VM, Context)));
87 return VM[V] = CE->getWithOperands(Ops);
88 } else if (ConstantVector *CP = dyn_cast<ConstantVector>(C)) {
89 for (User::op_iterator b = CP->op_begin(), i = b, e = CP->op_end();
91 Value *MV = MapValue(*i, VM, Context);
93 // This vector value must contain a reference to a global, make a new
94 // vector constant and return it.
96 std::vector<Constant*> Values;
97 Values.reserve(CP->getNumOperands());
98 for (User::op_iterator j = b; j != i; ++j)
99 Values.push_back(cast<Constant>(*j));
100 Values.push_back(cast<Constant>(MV));
101 for (++i; i != e; ++i)
102 Values.push_back(cast<Constant>(MapValue(*i, VM, Context)));
103 return VM[V] = Context.getConstantVector(Values);
108 } else if (MDNode *N = dyn_cast<MDNode>(C)) {
109 for (MDNode::const_elem_iterator b = N->elem_begin(), i = b,
110 e = N->elem_end(); i != e; ++i) {
113 Value *MV = MapValue(*i, VM, Context);
115 // This MDNode must contain a reference to a global, make a new MDNode
117 SmallVector<Value*, 8> Values;
118 Values.reserve(N->getNumElements());
119 for (MDNode::const_elem_iterator j = b; j != i; ++j)
120 Values.push_back(*j);
121 Values.push_back(MV);
122 for (++i; i != e; ++i)
123 Values.push_back(MapValue(*i, VM, Context));
124 return VM[V] = Context.getMDNode(Values.data(), Values.size());
130 llvm_unreachable("Unknown type of constant!");
137 /// RemapInstruction - Convert the instruction operands from referencing the
138 /// current values into those specified by ValueMap.
140 void llvm::RemapInstruction(Instruction *I, ValueMapTy &ValueMap) {
141 for (User::op_iterator op = I->op_begin(), E = I->op_end(); op != E; ++op) {
142 Value *V = MapValue(*op, ValueMap, I->getParent()->getContext());
143 assert(V && "Referenced value not in value map!");