[llvm] [AArch64] Initial compiler support for SVE unwind on Windows. (PR #138609)

[Benjamin Maxwell via llvm-commits]

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@@ -2757,10 +2853,27 @@ StackOffset AArch64FrameLowering::resolveFrameOffsetReference(
   }
 
   StackOffset ScalableOffset = {};
-  if (UseFP && !(isFixed || isCSR))
-    ScalableOffset = -SVEStackSize;
-  if (!UseFP && (isFixed || isCSR))
-    ScalableOffset = SVEStackSize;
+  bool FPAfterSVECalleeSaves =
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MacDue wrote:

I think `resolveFrameOffsetReference` will also be incorrect for SVE CSs, not sure if that's an issue, but I think there should at least be an assertion. 

https://github.com/llvm/llvm-project/pull/138609