[llvm] [AMDGPU] RA inserted scalar instructions can be at the BB top (PR #72140)

[Matt Arsenault via llvm-commits]

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@@ -846,8 +846,11 @@ class MachineBasicBlock
 
   /// Return the first instruction in MBB after I that is not a PHI, label or
   /// debug.  This is the correct point to insert copies at the beginning of a
-  /// basic block.
-  iterator SkipPHIsLabelsAndDebug(iterator I, bool SkipPseudoOp = true);
+  /// basic block. \p Reg is an optional argument passed during register
+  /// allocator to have additional target specific checks for its spill/copy
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arsenm wrote:

I'm thinking this should be a differently named function, specifically for the spill insert point

https://github.com/llvm/llvm-project/pull/72140