[llvm] r367365 - [DAGCombiner] Add an option to control whether or not to enable store merging.

[Wei Mi via llvm-commits]

Author: wmi
Date: Tue Jul 30 16:14:56 2019
New Revision: 367365

URL: http://llvm.org/viewvc/llvm-project?rev=367365&view=rev
Log:
[DAGCombiner] Add an option to control whether or not to enable store merging.

Add an option to control whether or not to enable store merging in dag combiner
so we can workaround some bugs more easily.

Differential Revision: https://reviews.llvm.org/D65482

Modified:
    llvm/trunk/lib/CodeGen/SelectionDAG/DAGCombiner.cpp

Modified: llvm/trunk/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/CodeGen/SelectionDAG/DAGCombiner.cpp?rev=367365&r1=367364&r2=367365&view=diff
==============================================================================
--- llvm/trunk/lib/CodeGen/SelectionDAG/DAGCombiner.cpp (original)
+++ llvm/trunk/lib/CodeGen/SelectionDAG/DAGCombiner.cpp Tue Jul 30 16:14:56 2019
@@ -111,6 +111,11 @@ static cl::opt<bool>
   MaySplitLoadIndex("combiner-split-load-index", cl::Hidden, cl::init(true),
                     cl::desc("DAG combiner may split indexing from loads"));
 
+static cl::opt<bool>
+    EnableStoreMerging("combiner-store-merging", cl::Hidden, cl::init(true),
+                       cl::desc("DAG combiner enable merging multiple stores "
+                                "into a wider store"));
+
 static cl::opt<unsigned> TokenFactorInlineLimit(
     "combiner-tokenfactor-inline-limit", cl::Hidden, cl::init(2048),
     cl::desc("Limit the number of operands to inline for Token Factors"));
@@ -15521,7 +15526,7 @@ bool DAGCombiner::checkMergeStoreCandida
 }
 
 bool DAGCombiner::MergeConsecutiveStores(StoreSDNode *St) {
-  if (OptLevel == CodeGenOpt::None)
+  if (OptLevel == CodeGenOpt::None || !EnableStoreMerging)
     return false;
 
   EVT MemVT = St->getMemoryVT();