Index: include/llvm/Transforms/Scalar/IndVarSimplify.h
===================================================================
--- /dev/null
+++ include/llvm/Transforms/Scalar/IndVarSimplify.h
@@ -0,0 +1,29 @@
+//===- IndVarSimplify.h - Induction Variable Simplification -----*- C++ -*-===//
+//
+//                     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 Induction Variable
+// Simplification pass.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_TRANSFORMS_SCALAR_INDVARSIMPLIFY_H
+#define LLVM_TRANSFORMS_SCALAR_INDVARSIMPLIFY_H
+
+#include "llvm/Analysis/LoopInfo.h"
+#include "llvm/IR/PassManager.h"
+
+namespace llvm {
+
+class IndVarSimplifyPass : public PassInfoMixin<IndVarSimplifyPass> {
+public:
+  PreservedAnalyses run(Loop &L, AnalysisManager<Loop> &AM);
+};
+}
+
+#endif // LLVM_TRANSFORMS_SCALAR_INDVARSIMPLIFY_H
Index: lib/Passes/PassBuilder.cpp
===================================================================
--- lib/Passes/PassBuilder.cpp
+++ lib/Passes/PassBuilder.cpp
@@ -70,6 +70,7 @@
 #include "llvm/Transforms/Scalar/EarlyCSE.h"
 #include "llvm/Transforms/Scalar/GVN.h"
 #include "llvm/Transforms/Scalar/GuardWidening.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"
Index: lib/Passes/PassRegistry.def
===================================================================
--- lib/Passes/PassRegistry.def
+++ lib/Passes/PassRegistry.def
@@ -158,4 +158,5 @@
 LOOP_PASS("no-op-loop", NoOpLoopPass())
 LOOP_PASS("print", PrintLoopPass(dbgs()))
 LOOP_PASS("simplify-cfg", LoopSimplifyCFGPass())
+LOOP_PASS("indvars", IndVarSimplifyPass())
 #undef LOOP_PASS
Index: lib/Transforms/Scalar/IndVarSimplify.cpp
===================================================================
--- lib/Transforms/Scalar/IndVarSimplify.cpp
+++ 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"
@@ -2214,6 +2216,29 @@
   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();
+
+  return getLoopPassPreservedAnalyses();
+}
+
 namespace {
 struct IndVarSimplifyLegacyPass : public LoopPass {
   static char ID; // Pass identification, replacement for typeid
Index: test/Transforms/IndVarSimplify/backedge-on-min-max.ll
===================================================================
--- test/Transforms/IndVarSimplify/backedge-on-min-max.ll
+++ test/Transforms/IndVarSimplify/backedge-on-min-max.ll
@@ -1,4 +1,5 @@
 ; RUN: opt < %s -indvars -S | FileCheck %s
+; RUN: opt -lcssa -loop-simplify -S < %s | opt -S -passes='require<targetir>,require<scalar-evolution>,require<domtree>,loop(indvars)'
 
 ;; --- signed ---
 
Index: test/Transforms/IndVarSimplify/iv-widen.ll
===================================================================
--- test/Transforms/IndVarSimplify/iv-widen.ll
+++ test/Transforms/IndVarSimplify/iv-widen.ll
@@ -1,4 +1,5 @@
 ; RUN: opt < %s -indvars -S | FileCheck %s
+; RUN: opt -lcssa -loop-simplify -S < %s | opt -S -passes='require<targetir>,require<scalar-evolution>,require<domtree>,loop(indvars)'
 
 ; Provide legal integer types.
 target datalayout = "n8:16:32:64"
Index: test/Transforms/IndVarSimplify/sharpen-range.ll
===================================================================
--- test/Transforms/IndVarSimplify/sharpen-range.ll
+++ test/Transforms/IndVarSimplify/sharpen-range.ll
@@ -1,4 +1,5 @@
 ;; RUN: opt -S < %s -indvars | FileCheck %s
+; RUN: opt -lcssa -loop-simplify -S < %s | opt -S -passes='require<targetir>,require<scalar-evolution>,require<domtree>,loop(indvars)'
 
 ;; Check if llvm can narrow !range metadata based on loop entry
 ;; predicates.