Normally an 'optnone' function goes through fast-isel, which does not
call DAGCombiner. But we ran into a case (on Windows) where the
calling convention causes argument lowering to bail out of fast-isel,
and we end up in CodeGenAndEmitDAG() which does run DAGCombiner.
So, we need to make DAGCombiner check for 'optnone' after all.
Commit includes the test that found this, plus another one that got
missed in the original optnone work.
llvm-svn: 221168
diff --git a/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp b/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
index 0d5caba..107f5a1 100644
--- a/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
@@ -1155,6 +1155,13 @@
LegalOperations = Level >= AfterLegalizeVectorOps;
LegalTypes = Level >= AfterLegalizeTypes;
+ // Early exit if this basic block is in an optnone function.
+ AttributeSet FnAttrs =
+ DAG.getMachineFunction().getFunction()->getAttributes();
+ if (FnAttrs.hasAttribute(AttributeSet::FunctionIndex,
+ Attribute::OptimizeNone))
+ return;
+
// Add all the dag nodes to the worklist.
for (SelectionDAG::allnodes_iterator I = DAG.allnodes_begin(),
E = DAG.allnodes_end(); I != E; ++I)