[PATCH] D104394: [MachineCopyPropagation] Fix differences in code gen when compiling with -g

[Kai Luo via Phabricator via llvm-commits]

lkail added inline comments.


================
Comment at: llvm/lib/CodeGen/MachineCopyPropagation.cpp:829
                     << "\n");
+  llvm::DenseMap<llvm::MCRegister, llvm::MachineInstr *> RegToCopies;
 
----------------
This looks unnecessary, can use `findCopyDefViaUnit` to find out corresponding MachineInstr.


================
Comment at: llvm/lib/CodeGen/MachineCopyPropagation.cpp:878
 
-      if (MO.readsReg())
+      if (MO.readsReg() && MO.isDebug()) {
+        //  Check if the register in the debug instruction is utilized
----------------
nit:
```
if (MO.readsReg()) {
  if (MO.isDebug()) {
    ...
  } else {
    ...
  }
}
```


================
Comment at: llvm/lib/CodeGen/MachineCopyPropagation.cpp:898
+    Register NewR = Copy->getOperand(1).getReg();
+    Register OldR = Copy->getOperand(0).getReg();
+    SmallVector<MachineInstr *> MaybeDeadDbgUsers(CopyDbgUsers[Copy].begin(),
----------------
nit: OldR -> Def, NewR -> Src for consistency.


CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D104394/new/

https://reviews.llvm.org/D104394