[PATCH] D78778: [AsmPrinter] Fix emitting CFI for debug when exceptions are not supported

[Fangrui Song via Phabricator via llvm-commits]

MaskRay added a comment.

I noticed that D76519 <https://reviews.llvm.org/D76519>



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Comment at: llvm/include/llvm/CodeGen/AsmPrinter.h:378
 
+  /// Currently emitting CFI unwind information is entangled with supporting
+  /// the exceptions. When ExceptionsType == ExceptionHandling::None, this
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"Currently emitting CFI unwind information is entangled with supporting ..." This is a remark. It has minor state compared with the main comment. It can be added at the end or omitted.


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Comment at: llvm/include/llvm/CodeGen/AsmPrinter.h:379
+  /// Currently emitting CFI unwind information is entangled with supporting
+  /// the exceptions. When ExceptionsType == ExceptionHandling::None, this
+  /// returns true if DWARF CFI unwind information should be emitted either
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`ExceptionsType` is not mentioned.


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Comment at: llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp:351
   switch (MAI->getExceptionHandlingType()) {
+  // We may want to emit CFI for debug or when `ForceDwarfFrameSection`.
+  case ExceptionHandling::None:
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This comment is not clear. Does it only apply to `None`?


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Comment at: llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp:1067
+bool AsmPrinter::usesCFIForDebug() const {
+  return MAI->getExceptionHandlingType() == ExceptionHandling::None &&
+         ((MMI->hasDebugInfo() && ModuleCFISection == CFISection::Debug) ||
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Does AMDGPU use `MAI->getExceptionHandlingType() == ExceptionHandling::None` for .debug_frame?

Why can't it use `DwarfCFI`?


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  https://reviews.llvm.org/D78778/new/

https://reviews.llvm.org/D78778