llvm-project/llvm/lib/Transforms/Utils/ValueMapper.cpp

134 lines
4.9 KiB
C++

//===- ValueMapper.cpp - Interface shared by lib/Transforms/Utils ---------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file defines the MapValue function, which is shared by various parts of
// the lib/Transforms/Utils library.
//
//===----------------------------------------------------------------------===//
#include "llvm/Transforms/Utils/ValueMapper.h"
#include "llvm/DerivedTypes.h" // For getNullValue(Type::Int32Ty)
#include "llvm/Constants.h"
#include "llvm/Function.h"
#include "llvm/Metadata.h"
#include "llvm/ADT/SmallVector.h"
#include "llvm/Support/ErrorHandling.h"
using namespace llvm;
Value *llvm::MapValue(const Value *V, ValueMapTy &VM) {
Value *&VMSlot = VM[V];
if (VMSlot) return VMSlot; // Does it exist in the map yet?
// NOTE: VMSlot can be invalidated by any reference to VM, which can grow the
// DenseMap. This includes any recursive calls to MapValue.
// Global values and metadata do not need to be seeded into the ValueMap if
// they are using the identity mapping.
if (isa<GlobalValue>(V) || isa<InlineAsm>(V) || isa<MetadataBase>(V))
return VMSlot = const_cast<Value*>(V);
Constant *C = const_cast<Constant*>(dyn_cast<Constant>(V));
if (C == 0) return 0;
if (isa<ConstantInt>(C) || isa<ConstantFP>(C) ||
isa<ConstantPointerNull>(C) || isa<ConstantAggregateZero>(C) ||
isa<UndefValue>(C) || isa<MDString>(C))
return VMSlot = C; // Primitive constants map directly
if (ConstantArray *CA = dyn_cast<ConstantArray>(C)) {
for (User::op_iterator b = CA->op_begin(), i = b, e = CA->op_end();
i != e; ++i) {
Value *MV = MapValue(*i, VM);
if (MV != *i) {
// This array must contain a reference to a global, make a new array
// and return it.
//
std::vector<Constant*> Values;
Values.reserve(CA->getNumOperands());
for (User::op_iterator j = b; j != i; ++j)
Values.push_back(cast<Constant>(*j));
Values.push_back(cast<Constant>(MV));
for (++i; i != e; ++i)
Values.push_back(cast<Constant>(MapValue(*i, VM)));
return VM[V] = ConstantArray::get(CA->getType(), Values);
}
}
return VM[V] = C;
}
if (ConstantStruct *CS = dyn_cast<ConstantStruct>(C)) {
for (User::op_iterator b = CS->op_begin(), i = b, e = CS->op_end();
i != e; ++i) {
Value *MV = MapValue(*i, VM);
if (MV != *i) {
// This struct must contain a reference to a global, make a new struct
// and return it.
//
std::vector<Constant*> Values;
Values.reserve(CS->getNumOperands());
for (User::op_iterator j = b; j != i; ++j)
Values.push_back(cast<Constant>(*j));
Values.push_back(cast<Constant>(MV));
for (++i; i != e; ++i)
Values.push_back(cast<Constant>(MapValue(*i, VM)));
return VM[V] = ConstantStruct::get(CS->getType(), Values);
}
}
return VM[V] = C;
}
if (ConstantExpr *CE = dyn_cast<ConstantExpr>(C)) {
std::vector<Constant*> Ops;
for (User::op_iterator i = CE->op_begin(), e = CE->op_end(); i != e; ++i)
Ops.push_back(cast<Constant>(MapValue(*i, VM)));
return VM[V] = CE->getWithOperands(Ops);
}
if (ConstantVector *CV = dyn_cast<ConstantVector>(C)) {
for (User::op_iterator b = CV->op_begin(), i = b, e = CV->op_end();
i != e; ++i) {
Value *MV = MapValue(*i, VM);
if (MV != *i) {
// This vector value must contain a reference to a global, make a new
// vector constant and return it.
//
std::vector<Constant*> Values;
Values.reserve(CV->getNumOperands());
for (User::op_iterator j = b; j != i; ++j)
Values.push_back(cast<Constant>(*j));
Values.push_back(cast<Constant>(MV));
for (++i; i != e; ++i)
Values.push_back(cast<Constant>(MapValue(*i, VM)));
return VM[V] = ConstantVector::get(Values);
}
}
return VM[V] = C;
}
if (BlockAddress *BA = dyn_cast<BlockAddress>(C)) {
Function *F = cast<Function>(MapValue(BA->getFunction(), VM));
BasicBlock *BB = cast_or_null<BasicBlock>(MapValue(BA->getBasicBlock(),VM));
return VM[V] = BlockAddress::get(F, BB ? BB : BA->getBasicBlock());
}
llvm_unreachable("Unknown type of constant!");
return 0;
}
/// RemapInstruction - Convert the instruction operands from referencing the
/// current values into those specified by ValueMap.
///
void llvm::RemapInstruction(Instruction *I, ValueMapTy &ValueMap) {
for (User::op_iterator op = I->op_begin(), E = I->op_end(); op != E; ++op) {
Value *V = MapValue(*op, ValueMap);
assert(V && "Referenced value not in value map!");
*op = V;
}
}