[llvm] [MachineOutliner] Preserve regmasks in calls to outlined functions (PR #120940)

[Amara Emerson via llvm-commits]

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@@ -1119,8 +1119,10 @@ class LLVM_ABI MachineFunction {
     OperandRecycler.deallocate(Cap, Array);
   }
 
-  /// Allocate and initialize a register mask with @p NumRegister bits.
-  uint32_t *allocateRegMask();
+  /// Allocate and initialize a register mask with all elements set to
+  /// \p InitValue and size reported via \p OutSize if nonnull.
+  uint32_t *allocateRegMask(uint32_t InitValue = 0,
+                            unsigned *OutSize = nullptr);
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aemerson wrote:

Agreed, it's a step in the right direction but I think we can do better.

https://github.com/llvm/llvm-project/pull/120940