1 files changed, 33 insertions, 15 deletions

diff --git a/lib/Transforms/IPO/PassManagerBuilder.cpp b/lib/Transforms/IPO/PassManagerBuilder.cpp
index 9a75050..d28d563 100644
--- a/lib/Transforms/IPO/PassManagerBuilder.cpp
+++ b/lib/Transforms/IPO/PassManagerBuilder.cpp
@@ -77,6 +77,10 @@ static cl::opt<bool>
 EnableMLSM("mlsm", cl::init(true), cl::Hidden,
            cl::desc("Enable motion of merged load and store"));
 
+static cl::opt<bool> EnableLoopInterchange(
+    "enable-loopinterchange", cl::init(false), cl::Hidden,
+    cl::desc("Enable the new, experimental LoopInterchange Pass"));
+
 PassManagerBuilder::PassManagerBuilder() {
     OptLevel = 2;
     SizeLevel = 0;
@@ -93,7 +97,6 @@ PassManagerBuilder::PassManagerBuilder() {
     DisableGVNLoadPRE = false;
     VerifyInput = false;
     VerifyOutput = false;
-    StripDebug = false;
     MergeFunctions = false;
 }
 
@@ -239,6 +242,8 @@ void PassManagerBuilder::populateModulePassManager(
   MPM.add(createIndVarSimplifyPass());        // Canonicalize indvars
   MPM.add(createLoopIdiomPass());             // Recognize idioms like memset.
   MPM.add(createLoopDeletionPass());          // Delete dead loops
+  if (EnableLoopInterchange)
+    MPM.add(createLoopInterchangePass()); // Interchange loops
 
   if (!DisableUnrollLoops)
     MPM.add(createSimpleLoopUnrollPass());    // Unroll small loops
@@ -305,8 +310,7 @@ void PassManagerBuilder::populateModulePassManager(
   // Re-rotate loops in all our loop nests. These may have fallout out of
   // rotated form due to GVN or other transformations, and the vectorizer relies
   // on the rotated form.
-  if (ExtraVectorizerPasses)
-    MPM.add(createLoopRotatePass());
+  MPM.add(createLoopRotatePass());
 
   MPM.add(createLoopVectorizePass(DisableUnrollLoops, LoopVectorize));
   // FIXME: Because of #pragma vectorize enable, the passes below are always
@@ -358,9 +362,20 @@ void PassManagerBuilder::populateModulePassManager(
   MPM.add(createCFGSimplificationPass());
   MPM.add(createInstructionCombiningPass());
 
-  if (!DisableUnrollLoops)
+  if (!DisableUnrollLoops) {
     MPM.add(createLoopUnrollPass());    // Unroll small loops
 
+    // This is a barrier pass to avoid combine LICM pass and loop unroll pass
+    // within same loop pass manager.
+    MPM.add(createInstructionSimplifierPass());
+
+    // Runtime unrolling will introduce runtime check in loop prologue. If the
+    // unrolled loop is a inner loop, then the prologue will be inside the
+    // outer loop. LICM pass can help to promote the runtime check out if the
+    // checked value is loop invariant.
+    MPM.add(createLICMPass());
+  }
+
   // After vectorization and unrolling, assume intrinsics may tell us more
   // about pointer alignments.
   MPM.add(createAlignmentFromAssumptionsPass());
@@ -454,6 +469,9 @@ void PassManagerBuilder::addLTOOptimizationPasses(legacy::PassManagerBase &PM) {
   // More loops are countable; try to optimize them.
   PM.add(createIndVarSimplifyPass());
   PM.add(createLoopDeletionPass());
+  if (EnableLoopInterchange)
+    PM.add(createLoopInterchangePass());
+
   PM.add(createLoopVectorizePass(true, LoopVectorize));
 
   // More scalar chains could be vectorized due to more alias information
@@ -473,10 +491,10 @@ void PassManagerBuilder::addLTOOptimizationPasses(legacy::PassManagerBase &PM) {
   addExtensionsToPM(EP_Peephole, PM);
 
   PM.add(createJumpThreadingPass());
+}
 
-  // Lower bitset metadata to bitsets.
-  PM.add(createLowerBitSetsPass());
-
+void PassManagerBuilder::addLateLTOOptimizationPasses(
+    legacy::PassManagerBase &PM) {
   // Delete basic blocks, which optimization passes may have killed.
   PM.add(createCFGSimplificationPass());
 
@@ -496,19 +514,19 @@ void PassManagerBuilder::populateLTOPassManager(legacy::PassManagerBase &PM) {
   if (VerifyInput)
     PM.add(createVerifierPass());
 
-  if (StripDebug)
-    PM.add(createStripSymbolsPass(true));
+  if (OptLevel > 1)
+    addLTOOptimizationPasses(PM);
 
-  if (VerifyInput)
-    PM.add(createDebugInfoVerifierPass());
+  // Lower bit sets to globals. This pass supports Clang's control flow
+  // integrity mechanisms (-fsanitize=cfi*) and needs to run at link time if CFI
+  // is enabled. The pass does nothing if CFI is disabled.
+  PM.add(createLowerBitSetsPass());
 
   if (OptLevel != 0)
-    addLTOOptimizationPasses(PM);
+    addLateLTOOptimizationPasses(PM);
 
-  if (VerifyOutput) {
+  if (VerifyOutput)
     PM.add(createVerifierPass());
-    PM.add(createDebugInfoVerifierPass());
-  }
 }
 
 inline PassManagerBuilder *unwrap(LLVMPassManagerBuilderRef P) {