[PATCH] D31403: [SDAG] Deal with deleted node in PromoteIntShiftOp

[Sanjay Patel via Phabricator via llvm-commits]

spatel added inline comments.


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Comment at: lib/CodeGen/SelectionDAG/DAGCombiner.cpp:1166-1169
+    if (Replace) {
+      AddToWorklist(N0.getNode());
       ReplaceLoadWithPromotedLoad(Op.getOperand(0).getNode(), N0.getNode());
+    }
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Only the 'PromoteOperand' path can set 'Replace' to true, right? Can you move this into that else clause, and move the 'Replace' declaration into that else clause too?


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Comment at: test/CodeGen/X86/pr32420.ll:32-46
+  %cast = zext i1 %lnot to i32
+  %load2 = load i16, i16* getelementptr inbounds (%struct.S, %struct.S* @a, i64 0, i32 0), align 4
+  %shl3 = shl i16 %load2, 12
+  %ashr4 = ashr i16 %shl3, 12
+  %cast527 = trunc i16 %ashr4 to i8
+  %t2 = load volatile i8, i8* @c, align 1
+  %or = or i8 %t2, %cast527
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The bug is triggered by the 16-bit shifts. Can you remove the memops, globals, and struct?


https://reviews.llvm.org/D31403