Index: llvm/trunk/lib/Transforms/Scalar/IndVarSimplify.cpp
===================================================================
--- llvm/trunk/lib/Transforms/Scalar/IndVarSimplify.cpp
+++ llvm/trunk/lib/Transforms/Scalar/IndVarSimplify.cpp
@@ -757,6 +757,9 @@
 
   const SCEVAddRecExpr* GetExtendedOperandRecurrence(NarrowIVDefUse DU);
 
+  const SCEV *GetSCEVByOpCode(const SCEV *LHS, const SCEV *RHS,
+                              unsigned OpCode) const;
+
   Instruction *WidenIVUse(NarrowIVDefUse DU, SCEVExpander &Rewriter);
 
   void pushNarrowIVUsers(Instruction *NarrowDef, Instruction *WideDef);
@@ -833,13 +836,30 @@
   }
 }
 
+const SCEV *WidenIV::GetSCEVByOpCode(const SCEV *LHS, const SCEV *RHS,
+                                     unsigned OpCode) const {
+  if (OpCode == Instruction::Add)
+    return SE->getAddExpr(LHS, RHS);
+  if (OpCode == Instruction::Sub)
+    return SE->getMinusSCEV(LHS, RHS);
+  if (OpCode == Instruction::Mul)
+    return SE->getMulExpr(LHS, RHS);
+
+  llvm_unreachable("Unsupported opcode.");
+  return nullptr;
+}
+
 /// No-wrap operations can transfer sign extension of their result to their
 /// operands. Generate the SCEV value for the widened operation without
 /// actually modifying the IR yet. If the expression after extending the
 /// operands is an AddRec for this loop, return it.
 const SCEVAddRecExpr* WidenIV::GetExtendedOperandRecurrence(NarrowIVDefUse DU) {
+
   // Handle the common case of add<nsw/nuw>
-  if (DU.NarrowUse->getOpcode() != Instruction::Add)
+  const unsigned OpCode = DU.NarrowUse->getOpcode();
+  // Only Add/Sub/Mul instructions supported yet.
+  if (OpCode != Instruction::Add && OpCode != Instruction::Sub &&
+      OpCode != Instruction::Mul)
     return nullptr;
 
   // One operand (NarrowDef) has already been extended to WideDef. Now determine
@@ -859,14 +879,13 @@
   else
     return nullptr;
 
-  // When creating this AddExpr, don't apply the current operations NSW or NUW
+  // When creating this SCEV expr, don't apply the current operations NSW or NUW
   // flags. This instruction may be guarded by control flow that the no-wrap
   // behavior depends on. Non-control-equivalent instructions can be mapped to
   // the same SCEV expression, and it would be incorrect to transfer NSW/NUW
   // semantics to those operations.
   const SCEVAddRecExpr *AddRec = dyn_cast<SCEVAddRecExpr>(
-    SE->getAddExpr(SE->getSCEV(DU.WideDef), ExtendOperExpr));
-
+      GetSCEVByOpCode(SE->getSCEV(DU.WideDef), ExtendOperExpr, OpCode));
   if (!AddRec || AddRec->getLoop() != L)
     return nullptr;
   return AddRec;
Index: llvm/trunk/test/Transforms/IndVarSimplify/2011-09-10-widen-nsw.ll
===================================================================
--- llvm/trunk/test/Transforms/IndVarSimplify/2011-09-10-widen-nsw.ll
+++ llvm/trunk/test/Transforms/IndVarSimplify/2011-09-10-widen-nsw.ll
@@ -1,6 +1,6 @@
 ; RUN: opt < %s -indvars -S | FileCheck %s
 ; Test WidenIV::GetExtendedOperandRecurrence.
-; add219 should be extended to i64 because it is nsw, even though its
+; %add, %sub and %mul should be extended to i64 because it is nsw, even though its
 ; sext cannot be hoisted outside the loop.
 
 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"
@@ -18,13 +18,22 @@
   br i1 undef, label %for.body170, label %for.body153
 
 ; CHECK: add nsw i64 %indvars.iv, 1
+; CHECK: sub nsw i64 %indvars.iv, 2
+; CHECK: mul nsw i64 %indvars.iv, 4
 for.body170:                                      ; preds = %for.body170, %for.body153
   %i2.19 = phi i32 [ %add249, %for.body170 ], [ 0, %for.body153 ]
-  %add219 = add nsw i32 %i2.19, 1
-  %idxprom220 = sext i32 %add219 to i64
+
+  %add = add nsw i32 %i2.19, 1
+  %add.idxprom = sext i32 %add to i64
+
+  %sub = sub nsw i32 %i2.19, 2
+  %sub.idxprom = sext i32 %sub to i64
+
+  %mul = mul nsw i32 %i2.19, 4
+  %mul.idxprom = sext i32 %mul to i64
+
   %add249 = add nsw i32 %i2.19, %shl132
   br label %for.body170
-
 for.end285:                                       ; preds = %entry
   ret void
 }