[PATCH] D81647: MIR Statepoint refactoring. Part 3: Spill GC Ptr regs.

[Serguei Katkov via Phabricator via llvm-commits]

skatkov added a comment.

Please fix the bug Philip mentioned and I think we are ready to land it.



================
Comment at: llvm/lib/CodeGen/FixupStatepointCallerSaved.cpp:130
+
+  // Skip deopt args
+  while (NumDeoptArgs--)
----------------
In InstrEmitter I see getStatepointGCArgStartIdx which does exactly the same what you need.
It also contains:
  // FIXME: need a better place for this. Put it in StackMaps?
Can you do it in a separate patch (w/o review) and just re-use this utility function here?


================
Comment at: llvm/lib/CodeGen/FixupStatepointCallerSaved.cpp:386
+      if (It != MBB->succ_end())
+        EHPad = *It;
+    }
----------------
This overall algorithm is very sensitive to alone EHPad.
Looking into machine verifier, I see that in some cases we can have more than one landing pad.
     if (LandingPadSuccs.size() > 1 &&
      !(AsmInfo &&
        AsmInfo->getExceptionHandlingType() == ExceptionHandling::SjLj &&
        BB && isa<SwitchInst>(BB->getTerminator())) &&
      !isScopedEHPersonality(classifyEHPersonality(F.getPersonalityFn())))
    report("MBB has more than one landing pad successor", MBB);
I would suggest to assert that here we have only one landing pad.


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D81647/new/

https://reviews.llvm.org/D81647