[llvm] [SFrames] Add FDEs for functions with .cfi_startproc (PR #154213)

[Indu Bhagat via llvm-commits]

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@@ -84,7 +150,19 @@ class SFrameEmitterImpl {
 
 void MCSFrameEmitter::emit(MCObjectStreamer &Streamer) {
   MCContext &Context = Streamer.getContext();
+  // If this target doesn't support sframes, return now. Gas doesn't warn in
+  // this case, but if we want to, it should be done at option-parsing time,
+  // rather than here.
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ibhagatgnu wrote:

I would agree that such error handling is ideally done at earlier (and not at emission time).

https://github.com/llvm/llvm-project/pull/154213