[PATCH] D67252: [IR] CallBrInst: scan+update arg list when indirect dest list changes

[Craig Topper via Phabricator via llvm-commits]

craig.topper added inline comments.


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Comment at: llvm/include/llvm/IR/Instructions.h:4085
   BasicBlock *getIndirectDest(unsigned i) const {
-    return cast<BasicBlock>(*(&Op<-1>() - getNumIndirectDests() + i));
+    return cast_or_null<BasicBlock>(*(&Op<-1>() - getNumIndirectDests() + i));
   }
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Why is this change needed?


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Comment at: llvm/lib/IR/Instructions.cpp:827
+  assert(getNumIndirectDests() > i && "IndirectDest # out of range for callbr");
+  if (BasicBlock *OldBB = getIndirectDest(i)) {
+    BlockAddress *Old = BlockAddress::get(OldBB);
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When would this fail?


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D67252/new/

https://reviews.llvm.org/D67252