[PATCH] D46129: [SelectionDAG] Improve selection of DBG_VALUE using a PHI node result

[Bjorn Pettersson via Phabricator via llvm-commits]

bjope added inline comments.


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Comment at: test/DebugInfo/X86/sdag-dbgvalue-phi-use-2.ll:47
+; CHECK-NEXT: DBG_VALUE 555, debug-use $noreg, !17
+; XXX: Shouldn't the following DBG_VALUE be placed after the add (ADD32rr).
+; CHECK-NEXT: DBG_VALUE debug-use [[REG2]], debug-use $noreg, !17
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This new test case actually expose another problem. It seems like the DBG_VALUE instructions sometimes are inserted before instead of after the SDNode that it is being associated with when building the selection DAG (at least for constants and these new phi-related nodes).

I'm thinking about looking into that later in a separate commit. This patch at least resurrects some earlier lost DBG_VALUE instructions, and puts them closer to their original position in the LLVM IR (even if they sometimes still are "off by one").


Repository:
  rL LLVM

https://reviews.llvm.org/D46129