[llvm] [llvm] Win x64 Unwind V2 1/n: Mark beginning and end of epilogs (PR #110024)

[Eli Friedman via llvm-commits]

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@@ -33,10 +33,12 @@ f:                                      # @f
 	.seh_stackalloc 32
 	.seh_endprologue
 	nop
+	.seh_startepilogue
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efriedma-quic wrote:

Please add a test somewhere for the ".seh_ directive must appear within an active frame" diagnostic.

https://github.com/llvm/llvm-project/pull/110024