[llvm] [AArch64] Fix SVE callee-save layout for nounwind functions on Windows (PR #156467)

[Benjamin Maxwell via llvm-commits]

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@@ -3319,6 +3318,7 @@ static void computeCalleeSaveRegisterPairs(
       ByteOffset += StackFillDir * StackHazardSize;
     LastReg = RPI.Reg1;
 
+    bool NeedsWinCFI = needsWinCFI(MF);
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MacDue wrote:

nit: Keep this at the top of the function (this is now in a loop). 

https://github.com/llvm/llvm-project/pull/156467