When the source has a series of assignments, users reasonably want to
have the debugger step through each one individually. Turn off the
combine for adjacent stores at -O0 so we get this behavior.
Possibly, DAGCombine shouldn't run at all at -O0, but that's for
another day; see PR22346.
Differential Revision: http://reviews.llvm.org/D7181
llvm-svn: 230659
diff --git a/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp b/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
index 0437f59..6129401 100644
--- a/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
@@ -10055,6 +10055,9 @@
}
bool DAGCombiner::MergeConsecutiveStores(StoreSDNode* St) {
+ if (OptLevel == CodeGenOpt::None)
+ return false;
+
EVT MemVT = St->getMemoryVT();
int64_t ElementSizeBytes = MemVT.getSizeInBits()/8;
bool NoVectors = DAG.getMachineFunction().getFunction()->hasFnAttribute(