7 files changed, 71 insertions, 10 deletions
diff --git a/llvm/include/llvm/InitializePasses.h b/llvm/include/llvm/InitializePasses.h
index df85092f97f..ff5398f48af 100644
--- a/llvm/include/llvm/InitializePasses.h
+++ b/llvm/include/llvm/InitializePasses.h
@@ -178,7 +178,7 @@ void initializeLoopExtractorPass(PassRegistry&);
 void initializeLoopInfoWrapperPassPass(PassRegistry&);
 void initializeLoopInterchangePass(PassRegistry &);
 void initializeLoopInstSimplifyPass(PassRegistry&);
-void initializeLoopRotatePass(PassRegistry&);
+void initializeLoopRotateLegacyPassPass(PassRegistry&);
 void initializeLoopSimplifyPass(PassRegistry&);
 void initializeLoopSimplifyCFGLegacyPassPass(PassRegistry&);
 void initializeLoopStrengthReducePass(PassRegistry&);
diff --git a/llvm/include/llvm/Transforms/Scalar/LoopRotation.h b/llvm/include/llvm/Transforms/Scalar/LoopRotation.h
new file mode 100644
index 00000000000..8dc4c5c675e
--- /dev/null
+++ b/llvm/include/llvm/Transforms/Scalar/LoopRotation.h
@@ -0,0 +1,32 @@
+//===- LoopRotation.h - Loop Rotation -------------------------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file provides the interface for the Loop Rotation pass.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_TRANSFORMS_SCALAR_LOOPROTATION_H
+#define LLVM_TRANSFORMS_SCALAR_LOOPROTATION_H
+
+#include "llvm/Analysis/LoopInfo.h"
+#include "llvm/IR/PassManager.h"
+
+namespace llvm {
+
+/// A simple loop rotation transformation.
+class LoopRotatePass : public PassInfoMixin<LoopRotatePass> {
+  unsigned MaxHeaderSize;
+public:
+  LoopRotatePass();
+  LoopRotatePass(unsigned MaxHeaderSize) : MaxHeaderSize(MaxHeaderSize) {}
+  PreservedAnalyses run(Loop &L, AnalysisManager<Loop> &AM);
+};
+}
+
+#endif // LLVM_TRANSFORMS_SCALAR_LOOPROTATION_H
diff --git a/llvm/lib/Passes/PassBuilder.cpp b/llvm/lib/Passes/PassBuilder.cpp
index 32790a63086..2dcd3342f38 100644
--- a/llvm/lib/Passes/PassBuilder.cpp
+++ b/llvm/lib/Passes/PassBuilder.cpp
@@ -57,6 +57,7 @@
 #include "llvm/Transforms/Scalar/ADCE.h"
 #include "llvm/Transforms/Scalar/DCE.h"
 #include "llvm/Transforms/Scalar/EarlyCSE.h"
+#include "llvm/Transforms/Scalar/LoopRotation.h"
 #include "llvm/Transforms/Scalar/LoopSimplifyCFG.h"
 #include "llvm/Transforms/Scalar/LowerExpectIntrinsic.h"
 #include "llvm/Transforms/Scalar/GVN.h"
diff --git a/llvm/lib/Passes/PassRegistry.def b/llvm/lib/Passes/PassRegistry.def
index 9d45890ff14..366ffbdc3f2 100644
--- a/llvm/lib/Passes/PassRegistry.def
+++ b/llvm/lib/Passes/PassRegistry.def
@@ -134,6 +134,7 @@ LOOP_ANALYSIS("no-op-loop", NoOpLoopAnalysis())
 #define LOOP_PASS(NAME, CREATE_PASS)
 #endif
 LOOP_PASS("invalidate<all>", InvalidateAllAnalysesPass())
+LOOP_PASS("rotate", LoopRotatePass())
 LOOP_PASS("no-op-loop", NoOpLoopPass())
 LOOP_PASS("print", PrintLoopPass(dbgs()))
 LOOP_PASS("simplify-cfg", LoopSimplifyCFGPass())
diff --git a/llvm/lib/Transforms/Scalar/LoopRotation.cpp b/llvm/lib/Transforms/Scalar/LoopRotation.cpp
index ac008288eaa..214f41790f9 100644
--- a/llvm/lib/Transforms/Scalar/LoopRotation.cpp
+++ b/llvm/lib/Transforms/Scalar/LoopRotation.cpp
@@ -11,7 +11,7 @@
 //
 //===----------------------------------------------------------------------===//
 
-#include "llvm/Transforms/Scalar.h"
+#include "llvm/Transforms/Scalar/LoopRotation.h"
 #include "llvm/ADT/Statistic.h"
 #include "llvm/Analysis/AliasAnalysis.h"
 #include "llvm/Analysis/BasicAliasAnalysis.h"
@@ -20,6 +20,7 @@
 #include "llvm/Analysis/InstructionSimplify.h"
 #include "llvm/Analysis/GlobalsModRef.h"
 #include "llvm/Analysis/LoopPass.h"
+#include "llvm/Analysis/LoopPassManager.h"
 #include "llvm/Analysis/ScalarEvolution.h"
 #include "llvm/Analysis/ScalarEvolutionAliasAnalysis.h"
 #include "llvm/Analysis/TargetTransformInfo.h"
@@ -32,6 +33,7 @@
 #include "llvm/Support/CommandLine.h"
 #include "llvm/Support/Debug.h"
 #include "llvm/Support/raw_ostream.h"
+#include "llvm/Transforms/Scalar.h"
 #include "llvm/Transforms/Utils/BasicBlockUtils.h"
 #include "llvm/Transforms/Utils/Local.h"
 #include "llvm/Transforms/Utils/LoopUtils.h"
@@ -562,15 +564,36 @@ static bool iterativelyRotateLoop(Loop *L, unsigned MaxHeaderSize, LoopInfo *LI,
   return MadeChange;
 }
 
+LoopRotatePass::LoopRotatePass() : MaxHeaderSize(DefaultRotationThreshold) {}
+
+PreservedAnalyses LoopRotatePass::run(Loop &L, AnalysisManager<Loop> &AM) {
+  auto &FAM = AM.getResult<FunctionAnalysisManagerLoopProxy>(L).getManager();
+  Function *F = L.getHeader()->getParent();
+
+  auto *LI = FAM.getCachedResult<LoopAnalysis>(*F);
+  const auto *TTI = FAM.getCachedResult<TargetIRAnalysis>(*F);
+  auto *AC = FAM.getCachedResult<AssumptionAnalysis>(*F);
+  assert((LI && TTI && AC) && "Analyses for loop rotation not available");
+
+  // Optional analyses.
+  auto *DT = FAM.getCachedResult<DominatorTreeAnalysis>(*F);
+  auto *SE = FAM.getCachedResult<ScalarEvolutionAnalysis>(*F);
+
+  bool Changed = iterativelyRotateLoop(&L, MaxHeaderSize, LI, TTI, AC, DT, SE);
+  if (!Changed)
+    return PreservedAnalyses::all();
+  return getLoopPassPreservedAnalyses();
+}
+
 namespace {
 
-class LoopRotate : public LoopPass {
+class LoopRotateLegacyPass : public LoopPass {
   unsigned MaxHeaderSize;
 
 public:
   static char ID; // Pass ID, replacement for typeid
-  LoopRotate(int SpecifiedMaxHeaderSize = -1) : LoopPass(ID) {
-    initializeLoopRotatePass(*PassRegistry::getPassRegistry());
+  LoopRotateLegacyPass(int SpecifiedMaxHeaderSize = -1) : LoopPass(ID) {
+    initializeLoopRotateLegacyPassPass(*PassRegistry::getPassRegistry());
     if (SpecifiedMaxHeaderSize == -1)
       MaxHeaderSize = DefaultRotationThreshold;
     else
@@ -602,13 +625,15 @@ public:
 };
 }
 
-char LoopRotate::ID = 0;
-INITIALIZE_PASS_BEGIN(LoopRotate, "loop-rotate", "Rotate Loops", false, false)
+char LoopRotateLegacyPass::ID = 0;
+INITIALIZE_PASS_BEGIN(LoopRotateLegacyPass, "loop-rotate", "Rotate Loops",
+                      false, false)
 INITIALIZE_PASS_DEPENDENCY(AssumptionCacheTracker)
 INITIALIZE_PASS_DEPENDENCY(LoopPass)
 INITIALIZE_PASS_DEPENDENCY(TargetTransformInfoWrapperPass)
-INITIALIZE_PASS_END(LoopRotate, "loop-rotate", "Rotate Loops", false, false)
+INITIALIZE_PASS_END(LoopRotateLegacyPass, "loop-rotate", "Rotate Loops",
+                    false, false)
 
 Pass *llvm::createLoopRotatePass(int MaxHeaderSize) {
-  return new LoopRotate(MaxHeaderSize);
+  return new LoopRotateLegacyPass(MaxHeaderSize);
 }
diff --git a/llvm/lib/Transforms/Scalar/Scalar.cpp b/llvm/lib/Transforms/Scalar/Scalar.cpp
index d3d6adad9c2..f1204c30403 100644
--- a/llvm/lib/Transforms/Scalar/Scalar.cpp
+++ b/llvm/lib/Transforms/Scalar/Scalar.cpp
@@ -53,7 +53,7 @@ void llvm::initializeScalarOpts(PassRegistry &Registry) {
   initializeLoopAccessAnalysisPass(Registry);
   initializeLoopInstSimplifyPass(Registry);
   initializeLoopInterchangePass(Registry);
-  initializeLoopRotatePass(Registry);
+  initializeLoopRotateLegacyPassPass(Registry);
   initializeLoopStrengthReducePass(Registry);
   initializeLoopRerollPass(Registry);
   initializeLoopUnrollPass(Registry);
diff --git a/llvm/test/Transforms/LoopRotate/basic.ll b/llvm/test/Transforms/LoopRotate/basic.ll
index 9c04fa28753..3d8ef7b4074 100644
--- a/llvm/test/Transforms/LoopRotate/basic.ll
+++ b/llvm/test/Transforms/LoopRotate/basic.ll
@@ -1,4 +1,6 @@
 ; RUN: opt -S -loop-rotate < %s | FileCheck %s
+; RUN: opt -S -passes='require<loops>,require<targetir>,require<assumptions>,loop(rotate)' < %s | FileCheck %s
+
 target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128-n8:16:32:64"
 target triple = "x86_64-apple-darwin10.0.0"