Index: llvm/trunk/lib/Transforms/Scalar/CorrelatedValuePropagation.cpp
===================================================================
--- llvm/trunk/lib/Transforms/Scalar/CorrelatedValuePropagation.cpp
+++ llvm/trunk/lib/Transforms/Scalar/CorrelatedValuePropagation.cpp
@@ -38,6 +38,7 @@
 STATISTIC(NumReturns,   "Number of return values propagated");
 STATISTIC(NumDeadCases, "Number of switch cases removed");
 STATISTIC(NumSDivs,     "Number of sdiv converted to udiv");
+STATISTIC(NumAShrs,     "Number of ashr converted to lshr");
 STATISTIC(NumSRems,     "Number of srem converted to urem");
 
 static cl::opt<bool> DontProcessAdds("cvp-dont-process-adds", cl::init(false));
@@ -384,6 +385,25 @@
   return true;
 }
 
+static bool processAShr(BinaryOperator *SDI, LazyValueInfo *LVI) {
+  if (SDI->getType()->isVectorTy() || hasLocalDefs(SDI))
+    return false;
+
+  Constant *Zero = ConstantInt::get(SDI->getType(), 0);
+  if (LVI->getPredicateAt(ICmpInst::ICMP_SGE, SDI->getOperand(0), Zero, SDI) !=
+      LazyValueInfo::True)
+    return false;
+
+  ++NumAShrs;
+  auto *BO = BinaryOperator::CreateLShr(SDI->getOperand(0), SDI->getOperand(1),
+                                        SDI->getName(), SDI);
+  BO->setIsExact(SDI->isExact());
+  SDI->replaceAllUsesWith(BO);
+  SDI->eraseFromParent();
+
+  return true;
+}
+
 static bool processAdd(BinaryOperator *AddOp, LazyValueInfo *LVI) {
   typedef OverflowingBinaryOperator OBO;
 
@@ -495,6 +515,9 @@
       case Instruction::SDiv:
         BBChanged |= processSDiv(cast<BinaryOperator>(II), LVI);
         break;
+      case Instruction::AShr:
+        BBChanged |= processAShr(cast<BinaryOperator>(II), LVI);
+        break;
       case Instruction::Add:
         BBChanged |= processAdd(cast<BinaryOperator>(II), LVI);
         break;
Index: llvm/trunk/test/Transforms/CorrelatedValuePropagation/ashr.ll
===================================================================
--- llvm/trunk/test/Transforms/CorrelatedValuePropagation/ashr.ll
+++ llvm/trunk/test/Transforms/CorrelatedValuePropagation/ashr.ll
@@ -0,0 +1,56 @@
+; RUN: opt < %s -correlated-propagation -S | FileCheck %s
+
+; CHECK-LABEL: @test1
+define void @test1(i32 %n) {
+entry:
+  br label %for.cond
+
+for.cond:                                         ; preds = %for.body, %entry
+  %a = phi i32 [ %n, %entry ], [ %shr, %for.body ]
+  %cmp = icmp sgt i32 %a, 1
+  br i1 %cmp, label %for.body, label %for.end
+
+for.body:                                         ; preds = %for.cond
+; CHECK: lshr i32 %a, 5
+  %shr = ashr i32 %a, 5
+  br label %for.cond
+
+for.end:                                          ; preds = %for.cond
+  ret void
+}
+
+;; Negative test to show transform doesn't happen unless n > 0.
+; CHECK-LABEL: @test2
+define void @test2(i32 %n) {
+entry:
+  br label %for.cond
+
+for.cond:                                         ; preds = %for.body, %entry
+  %a = phi i32 [ %n, %entry ], [ %shr, %for.body ]
+  %cmp = icmp sgt i32 %a, -2
+  br i1 %cmp, label %for.body, label %for.end
+
+for.body:                                         ; preds = %for.cond
+; CHECK: ashr i32 %a, 2
+  %shr = ashr i32 %a, 2
+  br label %for.cond
+
+for.end:                                          ; preds = %for.cond
+  ret void
+}
+
+;; Non looping test case.
+; CHECK-LABEL: @test3
+define void @test3(i32 %n) {
+entry:
+  %cmp = icmp sgt i32 %n, 0
+  br i1 %cmp, label %bb, label %exit
+
+bb:
+; CHECK: lshr exact i32 %n, 4
+  %shr = ashr exact i32 %n, 4
+  br label %exit
+
+exit:
+  ret void
+}