[clang] [llvm] [win][x64] Unwind v2 3/n: Add support for emitting unwind v2 information (equivalent to MSVC /d2epilogunwind) (PR #129142)

[Daniel Paoliello via llvm-commits]

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@@ -7788,6 +7788,10 @@ def import_call_optimization : Flag<["-"], "import-call-optimization">,
              "by the Windows kernel to enable import call optimization">,
     MarshallingInfoFlag<CodeGenOpts<"ImportCallOptimization">>;
 
+def epilog_unwind : Flag<["-"], "winx64-eh-unwindv2">,
+  HelpText<"Enable unwind v2 (epilog) information for x64 Windows">,
+  MarshallingInfoFlag<CodeGenOpts<"WinX64EHUnwindV2">>;
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dpaoliello wrote:

Took the opportunity to switch it to a bool flag as well, so that we can enable it by default at some point

https://github.com/llvm/llvm-project/pull/129142