Revamp the ValueMapper interfaces in a couple ways:
1. Take a flags argument instead of a bool. This makes
it more clear to the reader what it is used for.
2. Add a flag that says that "remapping a value not in the
map is ok".
3. Reimplement MapValue to share a bunch of code and be a lot
more efficient. For lookup failures, don't drop null values
into the map.
4. Using the new flag a bunch of code can vaporize in LinkModules
and LoopUnswitch, kill it.
No functionality change.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@123058 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Transforms/Utils/ValueMapper.cpp b/lib/Transforms/Utils/ValueMapper.cpp
index 9455e53..132c392 100644
--- a/lib/Transforms/Utils/ValueMapper.cpp
+++ b/lib/Transforms/Utils/ValueMapper.cpp
@@ -21,147 +21,106 @@
using namespace llvm;
Value *llvm::MapValue(const Value *V, ValueToValueMapTy &VM,
- bool ModuleLevelChanges) {
- TrackingVH<Value> &VMSlot = VM[V];
- if (VMSlot) return VMSlot; // Does it exist in the map yet?
+ RemapFlags Flags) {
+ ValueToValueMapTy::iterator I = VM.find(V);
- // NOTE: VMSlot can be invalidated by any reference to VM, which can grow the
- // DenseMap. This includes any recursive calls to MapValue.
-
+ // If the value already exists in the map, use it.
+ if (I != VM.end() && I->second) return I->second;
+
// Global values do not need to be seeded into the VM if they
// are using the identity mapping.
- if (isa<GlobalValue>(V) || isa<InlineAsm>(V) || isa<MDString>(V) ||
- (isa<MDNode>(V) && !cast<MDNode>(V)->isFunctionLocal() &&
- !ModuleLevelChanges))
- return VMSlot = const_cast<Value*>(V);
+ if (isa<GlobalValue>(V) || isa<InlineAsm>(V) || isa<MDString>(V))
+ return VM[V] = const_cast<Value*>(V);
if (const MDNode *MD = dyn_cast<MDNode>(V)) {
- // Start by assuming that we'll use the identity mapping.
- VMSlot = const_cast<Value*>(V);
-
+ // If this is a module-level metadata and we know that nothing at the module
+ // level is changing, then use an identity mapping.
+ if (!MD->isFunctionLocal() && (Flags & RF_NoModuleLevelChanges))
+ return VM[V] = const_cast<Value*>(V);
+
// Check all operands to see if any need to be remapped.
for (unsigned i = 0, e = MD->getNumOperands(); i != e; ++i) {
Value *OP = MD->getOperand(i);
- if (!OP || MapValue(OP, VM, ModuleLevelChanges) == OP) continue;
+ if (OP == 0 || MapValue(OP, VM, Flags) == OP) continue;
- // Ok, at least one operand needs remapping.
+ // Ok, at least one operand needs remapping. Create a dummy node in case
+ // we have a metadata cycle.
MDNode *Dummy = MDNode::getTemporary(V->getContext(), 0, 0);
VM[V] = Dummy;
SmallVector<Value*, 4> Elts;
Elts.reserve(MD->getNumOperands());
- for (i = 0; i != e; ++i)
- Elts.push_back(MD->getOperand(i) ?
- MapValue(MD->getOperand(i), VM, ModuleLevelChanges) : 0);
+ for (i = 0; i != e; ++i) {
+ Value *Op = MD->getOperand(i);
+ Elts.push_back(Op ? MapValue(Op, VM, Flags) : 0);
+ }
MDNode *NewMD = MDNode::get(V->getContext(), Elts.data(), Elts.size());
Dummy->replaceAllUsesWith(NewMD);
MDNode::deleteTemporary(Dummy);
return VM[V] = NewMD;
}
- // No operands needed remapping; keep the identity map.
- return const_cast<Value*>(V);
+ // No operands needed remapping. Use an identity mapping.
+ return VM[V] = const_cast<Value*>(V);
}
+ // Okay, this either must be a constant (which may or may not be mappable) or
+ // is something that is not in the mapping table.
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))
- 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, ModuleLevelChanges);
- 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,
- ModuleLevelChanges)));
- return VM[V] = ConstantArray::get(CA->getType(), Values);
- }
- }
- return VM[V] = C;
+ if (BlockAddress *BA = dyn_cast<BlockAddress>(C)) {
+ Function *F = cast<Function>(MapValue(BA->getFunction(), VM, Flags));
+ BasicBlock *BB = cast_or_null<BasicBlock>(MapValue(BA->getBasicBlock(), VM,
+ Flags));
+ return VM[V] = BlockAddress::get(F, BB ? BB : BA->getBasicBlock());
}
- 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, ModuleLevelChanges);
- 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,
- ModuleLevelChanges)));
- return VM[V] = ConstantStruct::get(CS->getType(), Values);
- }
- }
- return VM[V] = C;
- }
-
- if (ConstantExpr *CE = dyn_cast<ConstantExpr>(C)) {
+ for (unsigned i = 0, e = C->getNumOperands(); i != e; ++i) {
+ Value *Op = C->getOperand(i);
+ Value *Mapped = MapValue(Op, VM, Flags);
+ if (Mapped == C) continue;
+
+ // Okay, the operands don't all match. We've already processed some or all
+ // of the operands, set them up now.
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, ModuleLevelChanges)));
- return VM[V] = CE->getWithOperands(Ops);
+ Ops.reserve(C->getNumOperands());
+ for (unsigned j = 0; j != i; ++j)
+ Ops.push_back(cast<Constant>(C->getOperand(i)));
+ Ops.push_back(cast<Constant>(Mapped));
+
+ // Map the rest of the operands that aren't processed yet.
+ for (++i; i != e; ++i)
+ Ops.push_back(cast<Constant>(MapValue(C->getOperand(i), VM, Flags)));
+
+ if (ConstantExpr *CE = dyn_cast<ConstantExpr>(C))
+ return VM[V] = CE->getWithOperands(Ops);
+ if (ConstantArray *CA = dyn_cast<ConstantArray>(C))
+ return VM[V] = ConstantArray::get(CA->getType(), Ops);
+ if (ConstantStruct *CS = dyn_cast<ConstantStruct>(C))
+ return VM[V] = ConstantStruct::get(CS->getType(), Ops);
+ assert(isa<ConstantVector>(C) && "Unknown mapped constant type");
+ return VM[V] = ConstantVector::get(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, ModuleLevelChanges);
- 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,
- ModuleLevelChanges)));
- return VM[V] = ConstantVector::get(Values);
- }
- }
- return VM[V] = C;
- }
-
- BlockAddress *BA = cast<BlockAddress>(C);
- Function *F = cast<Function>(MapValue(BA->getFunction(), VM,
- ModuleLevelChanges));
- BasicBlock *BB = cast_or_null<BasicBlock>(MapValue(BA->getBasicBlock(),VM,
- ModuleLevelChanges));
- return VM[V] = BlockAddress::get(F, BB ? BB : BA->getBasicBlock());
+
+ // If we reach here, all of the operands of the constant match.
+ return VM[V] = C;
}
/// RemapInstruction - Convert the instruction operands from referencing the
/// current values into those specified by VMap.
///
void llvm::RemapInstruction(Instruction *I, ValueToValueMapTy &VMap,
- bool ModuleLevelChanges) {
+ RemapFlags Flags) {
// Remap operands.
for (User::op_iterator op = I->op_begin(), E = I->op_end(); op != E; ++op) {
- Value *V = MapValue(*op, VMap, ModuleLevelChanges);
- assert(V && "Referenced value not in value map!");
- *op = V;
+ Value *V = MapValue(*op, VMap, Flags);
+ // If we aren't ignoring missing entries, assert that something happened.
+ if (V != 0)
+ *op = V;
+ else
+ assert((Flags & RF_IgnoreMissingEntries) &&
+ "Referenced value not in value map!");
}
// Remap attached metadata.
@@ -170,7 +129,7 @@
for (SmallVectorImpl<std::pair<unsigned, MDNode *> >::iterator
MI = MDs.begin(), ME = MDs.end(); MI != ME; ++MI) {
Value *Old = MI->second;
- Value *New = MapValue(Old, VMap, ModuleLevelChanges);
+ Value *New = MapValue(Old, VMap, Flags);
if (New != Old)
I->setMetadata(MI->first, cast<MDNode>(New));
}