[llvm] [llvm] Support multiple save/restore points in mir (PR #119357)

[Michael Maitland via llvm-commits]

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@@ -295,6 +322,10 @@ class MachineFrameInfo {
   /// Has CSInfo been set yet?
   bool CSIValid = false;
 
+  CalleeSavedInfoPerBB CSInfoPerSave;
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michaelmaitland wrote:

If we combine SavePoints and CalleeSavedInfoPerBB and also combine RestorePoints with CSInfoPerRestore, then we may be able to drop these objects and save memory?

https://github.com/llvm/llvm-project/pull/119357