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

[Petr Penzin via llvm-commits]

================
@@ -622,7 +650,7 @@ static void insertCSRSaves(MachineBasicBlock &SaveBlock,
 
 /// Insert restore code for the callee-saved registers used in the function.
 static void insertCSRRestores(MachineBasicBlock &RestoreBlock,
-                              std::vector<CalleeSavedInfo> &CSI) {
+                              std::vector<CalleeSavedInfo> CSI) {
----------------
ppenzin wrote:

I suspect this is what reverses the order of which registers appear in tests, but I think that's OK.

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