[PATCH] D68816: [NFC] Replace a linked list in LiveDebugVariables pass with a DenseMap

[Adrian Prantl via Phabricator via llvm-commits]

aprantl added a comment.

This is a really nice performance win and the code looks nicer, too.



================
Comment at: llvm/lib/CodeGen/LiveDebugVariables.cpp:154
+class UserValueIdentity {
+private:
+  const DILocalVariable *Variable;// The debug info variable we are part of.
----------------
nit: 

```
/// The debug info variable we are part of.
 const DILocalVariable *Variable;
...
```


================
Comment at: llvm/lib/CodeGen/LiveDebugVariables.cpp:333
+namespace llvm {
+template <> struct DenseMapInfo<UserValueIdentity> {
+  static inline UserValueIdentity getEmptyKey() {
----------------
FYI. If you don't want to implement all this, you can also inherit from std::pair<std::pair<>>. (With a single pair this is a more obvious win.)


Repository:
  rL LLVM

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D68816/new/

https://reviews.llvm.org/D68816