MergedLoadStoreMotion pass
[oota-llvm.git] / lib / Transforms / IPO / PassManagerBuilder.cpp
index 38e1b8e166677be5d1d3b0c78b92732ad8feff87..701fb462b4fdad1e6b50bf1bcdee2f8fab2d4d0e 100644 (file)
@@ -53,6 +53,10 @@ static cl::opt<bool>
 RunLoopRerolling("reroll-loops", cl::Hidden,
                  cl::desc("Run the loop rerolling pass"));
 
+static cl::opt<bool> RunLoadCombine("combine-loads", cl::init(false),
+                                    cl::Hidden,
+                                    cl::desc("Run the load combining pass"));
+
 PassManagerBuilder::PassManagerBuilder() {
     OptLevel = 2;
     SizeLevel = 0;
@@ -65,6 +69,7 @@ PassManagerBuilder::PassManagerBuilder() {
     SLPVectorize = RunSLPVectorization;
     LoopVectorize = RunLoopVectorization;
     RerollLoops = RunLoopRerolling;
+    LoadCombine = RunLoadCombine;
 }
 
 PassManagerBuilder::~PassManagerBuilder() {
@@ -151,9 +156,9 @@ void PassManagerBuilder::populateModulePassManager(PassManagerBase &MPM) {
   if (!DisableUnitAtATime) {
     addExtensionsToPM(EP_ModuleOptimizerEarly, MPM);
 
+    MPM.add(createIPSCCPPass());              // IP SCCP
     MPM.add(createGlobalOptimizerPass());     // Optimize out global vars
 
-    MPM.add(createIPSCCPPass());              // IP SCCP
     MPM.add(createDeadArgEliminationPass());  // Dead argument elimination
 
     MPM.add(createInstructionCombiningPass());// Clean up after IPCP & DAE
@@ -202,8 +207,10 @@ void PassManagerBuilder::populateModulePassManager(PassManagerBase &MPM) {
     MPM.add(createSimpleLoopUnrollPass());    // Unroll small loops
   addExtensionsToPM(EP_LoopOptimizerEnd, MPM);
 
-  if (OptLevel > 1)
+  if (OptLevel > 1) {
+    MPM.add(createMergedLoadStoreMotionPass()); // Merge load/stores in diamond
     MPM.add(createGVNPass());                 // Remove redundancies
+  }
   MPM.add(createMemCpyOptPass());             // Remove memcpy / form memset
   MPM.add(createSCCPPass());                  // Constant prop with SCCP
 
@@ -236,6 +243,9 @@ void PassManagerBuilder::populateModulePassManager(PassManagerBase &MPM) {
       MPM.add(createLoopUnrollPass());
   }
 
+  if (LoadCombine)
+    MPM.add(createLoadCombinePass());
+
   MPM.add(createAggressiveDCEPass());         // Delete dead instructions
   MPM.add(createCFGSimplificationPass()); // Merge & remove BBs
   MPM.add(createInstructionCombiningPass());  // Clean up after everything.
@@ -338,6 +348,7 @@ void PassManagerBuilder::populateLTOPassManager(PassManagerBase &PM,
   PM.add(createGlobalsModRefPass()); // IP alias analysis.
 
   PM.add(createLICMPass());                 // Hoist loop invariants.
+  PM.add(createMergedLoadStoreMotionPass()); // Merge load/stores in diamonds
   PM.add(createGVNPass(DisableGVNLoadPRE)); // Remove redundancies.
   PM.add(createMemCpyOptPass());            // Remove dead memcpys.
 
@@ -352,6 +363,9 @@ void PassManagerBuilder::populateLTOPassManager(PassManagerBase &PM,
   // More scalar chains could be vectorized due to more alias information
   PM.add(createSLPVectorizerPass()); // Vectorize parallel scalar chains.
 
+  if (LoadCombine)
+    PM.add(createLoadCombinePass());
+
   // Cleanup and simplify the code after the scalar optimizations.
   PM.add(createInstructionCombiningPass());
   addExtensionsToPM(EP_Peephole, PM);