diff options
| -rw-r--r-- | llvm/lib/IR/Type.cpp | 21 |
1 files changed, 14 insertions, 7 deletions
diff --git a/llvm/lib/IR/Type.cpp b/llvm/lib/IR/Type.cpp index 4e7532cb268..0fb079c5ab7 100644 --- a/llvm/lib/IR/Type.cpp +++ b/llvm/lib/IR/Type.cpp @@ -342,18 +342,25 @@ bool FunctionType::isValidArgumentType(Type *ArgTy) { StructType *StructType::get(LLVMContext &Context, ArrayRef<Type*> ETypes, bool isPacked) { LLVMContextImpl *pImpl = Context.pImpl; - AnonStructTypeKeyInfo::KeyTy Key(ETypes, isPacked); - auto I = pImpl->AnonStructTypes.find_as(Key); - StructType *ST; + const AnonStructTypeKeyInfo::KeyTy Key(ETypes, isPacked); - if (I == pImpl->AnonStructTypes.end()) { - // Value not found. Create a new type! + StructType *ST; + // Since we only want to allocate a fresh struct type in case none is found + // and we don't want to perform two lookups (one for checking if existent and + // one for inserting the newly allocated one), here we instead lookup based on + // Key and update the reference to the struct type in-place to a newly + // allocated one if not found. + auto Insertion = pImpl->AnonStructTypes.insert_as(nullptr, Key); + if (Insertion.second) { + // The struct type was not found. Allocate one and update AnonStructTypes + // in-place. ST = new (Context.pImpl->TypeAllocator) StructType(Context); ST->setSubclassData(SCDB_IsLiteral); // Literal struct. ST->setBody(ETypes, isPacked); - Context.pImpl->AnonStructTypes.insert(ST); + *Insertion.first = ST; } else { - ST = *I; + // The struct type was found. Just return it. + ST = *Insertion.first; } return ST; |
