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/DerivedTypes.h" // For getNullValue(Type::Int32Ty)
17 #include "llvm/Constants.h"
18 #include "llvm/Function.h"
19 #include "llvm/IntrinsicInst.h"
20 #include "llvm/Metadata.h"
21 #include "llvm/ADT/SmallVector.h"
22 #include "llvm/Support/ErrorHandling.h"
25 Value *llvm::MapValue(const Value *V, ValueMapTy &VM) {
26 Value *&VMSlot = VM[V];
27 if (VMSlot) return VMSlot; // Does it exist in the map yet?
29 // NOTE: VMSlot can be invalidated by any reference to VM, which can grow the
30 // DenseMap. This includes any recursive calls to MapValue.
32 // Global values and metadata do not need to be seeded into the ValueMap if
33 // they are using the identity mapping.
34 if (isa<GlobalValue>(V) || isa<InlineAsm>(V) || isa<MetadataBase>(V))
35 return VMSlot = const_cast<Value*>(V);
37 Constant *C = const_cast<Constant*>(dyn_cast<Constant>(V));
40 if (isa<ConstantInt>(C) || isa<ConstantFP>(C) ||
41 isa<ConstantPointerNull>(C) || isa<ConstantAggregateZero>(C) ||
42 isa<UndefValue>(C) || isa<MDString>(C))
43 return VMSlot = C; // Primitive constants map directly
45 if (ConstantArray *CA = dyn_cast<ConstantArray>(C)) {
46 for (User::op_iterator b = CA->op_begin(), i = b, e = CA->op_end();
48 Value *MV = MapValue(*i, VM);
50 // This array must contain a reference to a global, make a new array
53 std::vector<Constant*> Values;
54 Values.reserve(CA->getNumOperands());
55 for (User::op_iterator j = b; j != i; ++j)
56 Values.push_back(cast<Constant>(*j));
57 Values.push_back(cast<Constant>(MV));
58 for (++i; i != e; ++i)
59 Values.push_back(cast<Constant>(MapValue(*i, VM)));
60 return VM[V] = ConstantArray::get(CA->getType(), Values);
66 if (ConstantStruct *CS = dyn_cast<ConstantStruct>(C)) {
67 for (User::op_iterator b = CS->op_begin(), i = b, e = CS->op_end();
69 Value *MV = MapValue(*i, VM);
71 // This struct must contain a reference to a global, make a new struct
74 std::vector<Constant*> Values;
75 Values.reserve(CS->getNumOperands());
76 for (User::op_iterator j = b; j != i; ++j)
77 Values.push_back(cast<Constant>(*j));
78 Values.push_back(cast<Constant>(MV));
79 for (++i; i != e; ++i)
80 Values.push_back(cast<Constant>(MapValue(*i, VM)));
81 return VM[V] = ConstantStruct::get(CS->getType(), Values);
87 if (ConstantExpr *CE = dyn_cast<ConstantExpr>(C)) {
88 std::vector<Constant*> Ops;
89 for (User::op_iterator i = CE->op_begin(), e = CE->op_end(); i != e; ++i)
90 Ops.push_back(cast<Constant>(MapValue(*i, VM)));
91 return VM[V] = CE->getWithOperands(Ops);
94 if (ConstantVector *CV = dyn_cast<ConstantVector>(C)) {
95 for (User::op_iterator b = CV->op_begin(), i = b, e = CV->op_end();
97 Value *MV = MapValue(*i, VM);
99 // This vector value must contain a reference to a global, make a new
100 // vector constant and return it.
102 std::vector<Constant*> Values;
103 Values.reserve(CV->getNumOperands());
104 for (User::op_iterator j = b; j != i; ++j)
105 Values.push_back(cast<Constant>(*j));
106 Values.push_back(cast<Constant>(MV));
107 for (++i; i != e; ++i)
108 Values.push_back(cast<Constant>(MapValue(*i, VM)));
109 return VM[V] = ConstantVector::get(Values);
115 if (BlockAddress *BA = dyn_cast<BlockAddress>(C)) {
116 Function *F = cast<Function>(MapValue(BA->getFunction(), VM));
117 BasicBlock *BB = cast_or_null<BasicBlock>(MapValue(BA->getBasicBlock(),VM));
118 return VM[V] = BlockAddress::get(F, BB ? BB : BA->getBasicBlock());
121 llvm_unreachable("Unknown type of constant!");
125 /// RemapInstruction - Convert the instruction operands from referencing the
126 /// current values into those specified by ValueMap.
128 void llvm::RemapInstruction(Instruction *I, ValueMapTy &ValueMap) {
129 for (User::op_iterator op = I->op_begin(), E = I->op_end(); op != E; ++op) {
130 Value *V = MapValue(*op, ValueMap);
131 assert(V && "Referenced value not in value map!");
135 // Map llvm.dbg.declare instruction's first operand, which points to
136 // alloca instruction through MDNode. Since MDNodes are not counted as normal
137 // uses, this will fall through cracks otherwise.
138 const DbgDeclareInst *DDI = dyn_cast<DbgDeclareInst>(I);
141 Value *AddrInsn = DDI->getAddress();
142 if (!AddrInsn) return;
144 ValueMapTy::iterator VMI = ValueMap.find(AddrInsn);
145 if (VMI == ValueMap.end()) return;
147 Value *Elts[] = { VMI->second };
148 MDNode *NewAddr = MDNode::get(AddrInsn->getContext(), Elts, 1);
149 I->setOperand(1, NewAddr);