[PATCH] D101415: [CSSPGO] Fix an AV caused by a block that has only pseudo pseudo instructions.

[Wenlei He via Phabricator via llvm-commits]

wenlei added a comment.

So without this fix, it would AV as well if a block only had dbg instruction?



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Comment at: llvm/lib/CodeGen/RegAllocGreedy.cpp:1328
+    auto FirstNonDebugInstr = MBB->getFirstNonDebugInstr();
+    if (FirstNonDebugInstr != MBB->end() &&
+        SlotIndex::isEarlierInstr(LIS->getInstructionIndex(*FirstNonDebugInstr),
----------------
Without slot index for dbg or probe, we don't know whether the MBB is before the split, is it safe to allow insertion of spill there? 


Repository:
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  https://reviews.llvm.org/D101415/new/

https://reviews.llvm.org/D101415