[PM] Port IndVarSimplify to the new pass manager

Summary:
There are some rough corners, since the new pass manager doesn't have
(as far as I can tell) LoopSimplify and LCSSA, so I've updated the
tests to run them separately in the old pass manager in the lit tests.
We also don't have an equivalent for AU.setPreservesCFG() in the new
pass manager, so I've left a FIXME.

Reviewers: bogner, chandlerc, davide

Subscribers: sanjoy, mcrosier, llvm-commits

Differential Revision: http://reviews.llvm.org/D20783

llvm-svn: 271846

3 files changed, 29 insertions, 0 deletions

diff --git a/llvm/lib/Passes/PassBuilder.cpp b/llvm/lib/Passes/PassBuilder.cpp
index fca3e2534ed..ffffd3cdae9 100644
--- a/llvm/lib/Passes/PassBuilder.cpp
+++ b/llvm/lib/Passes/PassBuilder.cpp
@@ -72,6 +72,7 @@
 #include "llvm/Transforms/Scalar/EarlyCSE.h"
 #include "llvm/Transforms/Scalar/GuardWidening.h"
 #include "llvm/Transforms/Scalar/GVN.h"
+#include "llvm/Transforms/Scalar/IndVarSimplify.h"
 #include "llvm/Transforms/Scalar/LoopRotation.h"
 #include "llvm/Transforms/Scalar/LoopSimplifyCFG.h"
 #include "llvm/Transforms/Scalar/LowerAtomic.h"
diff --git a/llvm/lib/Passes/PassRegistry.def b/llvm/lib/Passes/PassRegistry.def
index e95e1975e4e..9d4b848b75e 100644
--- a/llvm/lib/Passes/PassRegistry.def
+++ b/llvm/lib/Passes/PassRegistry.def
@@ -164,4 +164,5 @@ LOOP_PASS("rotate", LoopRotatePass())
 LOOP_PASS("no-op-loop", NoOpLoopPass())
 LOOP_PASS("print", PrintLoopPass(dbgs()))
 LOOP_PASS("simplify-cfg", LoopSimplifyCFGPass())
+LOOP_PASS("indvars", IndVarSimplifyPass())
 #undef LOOP_PASS
diff --git a/llvm/lib/Transforms/Scalar/IndVarSimplify.cpp b/llvm/lib/Transforms/Scalar/IndVarSimplify.cpp
index 24fc872d7a0..2e5807b7470 100644
--- a/llvm/lib/Transforms/Scalar/IndVarSimplify.cpp
+++ b/llvm/lib/Transforms/Scalar/IndVarSimplify.cpp
@@ -24,12 +24,14 @@
 //
 //===----------------------------------------------------------------------===//
 
+#include "llvm/Transforms/Scalar/IndVarSimplify.h"
 #include "llvm/Transforms/Scalar.h"
 #include "llvm/ADT/SmallVector.h"
 #include "llvm/ADT/Statistic.h"
 #include "llvm/Analysis/GlobalsModRef.h"
 #include "llvm/Analysis/LoopInfo.h"
 #include "llvm/Analysis/LoopPass.h"
+#include "llvm/Analysis/LoopPassManager.h"
 #include "llvm/Analysis/ScalarEvolutionExpander.h"
 #include "llvm/Analysis/ScalarEvolutionAliasAnalysis.h"
 #include "llvm/Analysis/TargetLibraryInfo.h"
@@ -2212,6 +2214,31 @@ bool IndVarSimplify::run(Loop *L) {
   return Changed;
 }
 
+PreservedAnalyses IndVarSimplifyPass::run(Loop &L, AnalysisManager<Loop> &AM) {
+  auto &FAM = AM.getResult<FunctionAnalysisManagerLoopProxy>(L).getManager();
+  Function *F = L.getHeader()->getParent();
+  const DataLayout &DL = F->getParent()->getDataLayout();
+
+  auto *LI = FAM.getCachedResult<LoopAnalysis>(*F);
+  auto *SE = FAM.getCachedResult<ScalarEvolutionAnalysis>(*F);
+  auto *DT = FAM.getCachedResult<DominatorTreeAnalysis>(*F);
+
+  assert((LI && SE && DT) &&
+         "Analyses required for indvarsimplify not available!");
+
+  // Optional analyses.
+  auto *TTI = FAM.getCachedResult<TargetIRAnalysis>(*F);
+  auto *TLI = FAM.getCachedResult<TargetLibraryAnalysis>(*F);
+
+  IndVarSimplify IVS(LI, SE, DT, DL, TLI, TTI);
+  if (!IVS.run(&L))
+    return PreservedAnalyses::all();
+
+  // FIXME: once we have an equivalent of AU.setPreservesCFG() in the
+  // new pass manager, we should use that here.
+  return getLoopPassPreservedAnalyses();
+}
+
 namespace {
 struct IndVarSimplifyLegacyPass : public LoopPass {
   static char ID; // Pass identification, replacement for typeid