[PATCH] D122634: [RISCV] Do not outline CFI instructions when they are needed in EH

[Wang Pengcheng via Phabricator via llvm-commits]

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We saw a failure caused by unwinding with incomplete CFIs, so we
can't outline CFI instructions when they are needed in EH.


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D122634

Files:
  llvm/lib/Target/RISCV/RISCVInstrInfo.cpp


Index: llvm/lib/Target/RISCV/RISCVInstrInfo.cpp
===================================================================
--- llvm/lib/Target/RISCV/RISCVInstrInfo.cpp
+++ llvm/lib/Target/RISCV/RISCVInstrInfo.cpp
@@ -1246,7 +1246,12 @@
   if (MI.isPosition()) {
     // We can manually strip out CFI instructions later.
     if (MI.isCFIInstruction())
-      return outliner::InstrType::Invisible;
+      // If current function has exception handling code, we can't outline &
+      // strip these CFI instructions since it may break .eh_frame section
+      // needed in unwinding.
+      return MI.getMF()->getFunction().needsUnwindTableEntry()
+                 ? outliner::InstrType::Illegal
+                 : outliner::InstrType::Invisible;
 
     return outliner::InstrType::Illegal;
   }


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