From b5fa5fcecc97168a72c9533c84cf297c018b957c Mon Sep 17 00:00:00 2001 From: Chris Lattner Date: Sat, 8 Jan 2011 08:15:20 +0000 Subject: 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 --- lib/Transforms/Utils/ValueMapper.cpp | 169 +++++++++++++---------------------- 1 file changed, 64 insertions(+), 105 deletions(-) (limited to 'lib/Transforms/Utils/ValueMapper.cpp') diff --git a/lib/Transforms/Utils/ValueMapper.cpp b/lib/Transforms/Utils/ValueMapper.cpp index 9455e532b0..132c392039 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 &VMSlot = VM[V]; - if (VMSlot) return VMSlot; // Does it exist in the map yet? + RemapFlags Flags) { + ValueToValueMapTy::iterator I = VM.find(V); + + // If the value already exists in the map, use it. + if (I != VM.end() && I->second) return I->second; - // NOTE: VMSlot can be invalidated by any reference to VM, which can grow the - // DenseMap. This includes any recursive calls to MapValue. - // Global values do not need to be seeded into the VM if they // are using the identity mapping. - if (isa(V) || isa(V) || isa(V) || - (isa(V) && !cast(V)->isFunctionLocal() && - !ModuleLevelChanges)) - return VMSlot = const_cast(V); + if (isa(V) || isa(V) || isa(V)) + return VM[V] = const_cast(V); if (const MDNode *MD = dyn_cast(V)) { - // Start by assuming that we'll use the identity mapping. - VMSlot = const_cast(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(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 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(V); + // No operands needed remapping. Use an identity mapping. + return VM[V] = const_cast(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(dyn_cast(V)); if (C == 0) return 0; - if (isa(C) || isa(C) || - isa(C) || isa(C) || - isa(C)) - return VMSlot = C; // Primitive constants map directly - - if (ConstantArray *CA = dyn_cast(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 Values; - Values.reserve(CA->getNumOperands()); - for (User::op_iterator j = b; j != i; ++j) - Values.push_back(cast(*j)); - Values.push_back(cast(MV)); - for (++i; i != e; ++i) - Values.push_back(cast(MapValue(*i, VM, - ModuleLevelChanges))); - return VM[V] = ConstantArray::get(CA->getType(), Values); - } - } - return VM[V] = C; + if (BlockAddress *BA = dyn_cast(C)) { + Function *F = cast(MapValue(BA->getFunction(), VM, Flags)); + BasicBlock *BB = cast_or_null(MapValue(BA->getBasicBlock(), VM, + Flags)); + return VM[V] = BlockAddress::get(F, BB ? BB : BA->getBasicBlock()); } - if (ConstantStruct *CS = dyn_cast(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 Values; - Values.reserve(CS->getNumOperands()); - for (User::op_iterator j = b; j != i; ++j) - Values.push_back(cast(*j)); - Values.push_back(cast(MV)); - for (++i; i != e; ++i) - Values.push_back(cast(MapValue(*i, VM, - ModuleLevelChanges))); - return VM[V] = ConstantStruct::get(CS->getType(), Values); - } - } - return VM[V] = C; - } - - if (ConstantExpr *CE = dyn_cast(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 Ops; - for (User::op_iterator i = CE->op_begin(), e = CE->op_end(); i != e; ++i) - Ops.push_back(cast(MapValue(*i, VM, ModuleLevelChanges))); - return VM[V] = CE->getWithOperands(Ops); - } - - if (ConstantVector *CV = dyn_cast(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 Values; - Values.reserve(CV->getNumOperands()); - for (User::op_iterator j = b; j != i; ++j) - Values.push_back(cast(*j)); - Values.push_back(cast(MV)); - for (++i; i != e; ++i) - Values.push_back(cast(MapValue(*i, VM, - ModuleLevelChanges))); - return VM[V] = ConstantVector::get(Values); - } - } - return VM[V] = C; + Ops.reserve(C->getNumOperands()); + for (unsigned j = 0; j != i; ++j) + Ops.push_back(cast(C->getOperand(i))); + Ops.push_back(cast(Mapped)); + + // Map the rest of the operands that aren't processed yet. + for (++i; i != e; ++i) + Ops.push_back(cast(MapValue(C->getOperand(i), VM, Flags))); + + if (ConstantExpr *CE = dyn_cast(C)) + return VM[V] = CE->getWithOperands(Ops); + if (ConstantArray *CA = dyn_cast(C)) + return VM[V] = ConstantArray::get(CA->getType(), Ops); + if (ConstantStruct *CS = dyn_cast(C)) + return VM[V] = ConstantStruct::get(CS->getType(), Ops); + assert(isa(C) && "Unknown mapped constant type"); + return VM[V] = ConstantVector::get(Ops); } - - BlockAddress *BA = cast(C); - Function *F = cast(MapValue(BA->getFunction(), VM, - ModuleLevelChanges)); - BasicBlock *BB = cast_or_null(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 @@ void llvm::RemapInstruction(Instruction *I, ValueToValueMapTy &VMap, for (SmallVectorImpl >::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(New)); } -- cgit v1.2.3-18-g5258