Index: llvm/trunk/lib/Transforms/Scalar/LoopInterchange.cpp
===================================================================
--- llvm/trunk/lib/Transforms/Scalar/LoopInterchange.cpp
+++ llvm/trunk/lib/Transforms/Scalar/LoopInterchange.cpp
@@ -1112,7 +1112,8 @@
   }
   // If outer loop has dependence and inner loop is loop independent then it is
   // profitable to interchange to enable parallelism.
-  return true;
+  // If there are no dependences, interchanging will not improve anything.
+  return !DepMatrix.empty();
 }
 
 bool LoopInterchangeProfitability::isProfitable(unsigned InnerLoopId,
Index: llvm/trunk/test/Transforms/LoopInterchange/interchange-no-deps.ll
===================================================================
--- llvm/trunk/test/Transforms/LoopInterchange/interchange-no-deps.ll
+++ llvm/trunk/test/Transforms/LoopInterchange/interchange-no-deps.ll
@@ -1,31 +1,94 @@
-; RUN: opt < %s -loop-interchange -verify-dom-info -verify-loop-info -S \
-; RUN:     -pass-remarks=loop-interchange 2>&1 | FileCheck %s
-; CHECK: Loop interchanged with enclosing loop.
+; RUN: opt < %s -loop-interchange -simplifycfg -pass-remarks-output=%t \
+; RUN:     -pass-remarks=loop-interchange -pass-remarks-missed=loop-interchange -stats -S 2>&1 \
+; RUN:     | FileCheck -check-prefix=STATS %s
+; RUN: FileCheck -input-file %t %s
 
-; no_deps_interchange just access a single nested array and can be interchange.
 
-define i32 @no_deps_interchange([1024 x i32]* nocapture %Arr, i32 %k) local_unnamed_addr #0 {
+; no_deps_interchange just accesses a single nested array and can be interchange.
+; CHECK:      Name:       Interchanged
+; CHECK-NEXT: Function:   no_deps_interchange
+define i32 @no_deps_interchange([1024 x i32]* nocapture %Arr) local_unnamed_addr #0 {
 entry:
-  br label %for.body
+  br label %for1.header
 
-for.body:                                         ; preds = %entry, %for.cond.cleanup3
-  %indvars.iv19 = phi i64 [ 0, %entry ], [ %indvars.iv.next20, %for.cond.cleanup3 ]
-  br label %for.body4
+for1.header:                                         ; preds = %entry, %for1.inc
+  %indvars.iv19 = phi i64 [ 0, %entry ], [ %indvars.iv.next20, %for1.inc ]
+  br label %for2
 
-for.body4:                                        ; preds = %for.body, %for.body4
-  %indvars.iv = phi i64 [ 0, %for.body ], [ %indvars.iv.next, %for.body4 ]
+for2:                                        ; preds = %for1.header, %for2
+  %indvars.iv = phi i64 [ 0, %for1.header ], [ %indvars.iv.next, %for2 ]
   %arrayidx6 = getelementptr inbounds [1024 x i32], [1024 x i32]* %Arr, i64 %indvars.iv, i64 %indvars.iv19
   store i32 0, i32* %arrayidx6, align 4
   %indvars.iv.next = add nuw nsw i64 %indvars.iv, 1
   %exitcond = icmp ne i64 %indvars.iv.next, 1024
-  br i1 %exitcond, label %for.body4, label %for.cond.cleanup3
+  br i1 %exitcond, label %for2, label %for1.inc
 
-for.cond.cleanup3:                                ; preds = %for.body4
+for1.inc:
   %indvars.iv.next20 = add nuw nsw i64 %indvars.iv19, 1
   %exitcond21 = icmp ne i64 %indvars.iv.next20, 1024
-  br i1 %exitcond21, label %for.body, label %for.cond.cleanup
+  br i1 %exitcond21, label %for1.header, label %exit
 
+exit:                                 ; preds = %for1.inc
+  ret i32 0
+
+}
 
-for.cond.cleanup:                                 ; preds = %for.cond.cleanup3
+; Only the inner loop induction variable is used for memory accesses.
+; Interchanging is not beneficial.
+; CHECK:      Name:       InterchangeNotProfitable
+; CHECK-NEXT: Function:   no_bad_order
+define i32 @no_bad_order(i32* %Arr) {
+entry:
+  br label %for1.header
+
+for1.header:                                         ; preds = %entry, %for1.inc
+  %indvars.iv19 = phi i64 [ 0, %entry ], [ %indvars.iv.next20, %for1.inc ]
+  br label %for2
+
+for2:                                        ; preds = %for1.header, %for2
+  %indvars.iv = phi i64 [ 0, %for1.header ], [ %indvars.iv.next, %for2 ]
+  %arrayidx6 = getelementptr inbounds i32, i32* %Arr, i64 %indvars.iv
+  store i32 0, i32* %arrayidx6, align 4
+  %indvars.iv.next = add nuw nsw i64 %indvars.iv, 1
+  %exitcond = icmp ne i64 %indvars.iv.next, 1024
+  br i1 %exitcond, label %for2, label %for1.inc
+
+for1.inc:
+  %indvars.iv.next20 = add nuw nsw i64 %indvars.iv19, 1
+  %exitcond21 = icmp ne i64 %indvars.iv.next20, 1024
+  br i1 %exitcond21, label %for1.header, label %exit
+
+exit:                                 ; preds = %for1.inc
   ret i32 0
 }
+
+; No memory access using any induction variables, interchanging not beneficial.
+; CHECK:      Name:        InterchangeNotProfitable
+; CHECK-NEXT: Function:    no_mem_instrs
+define i32 @no_mem_instrs(i64* %ptr) {
+entry:
+  br label %for1.header
+
+for1.header:                                         ; preds = %entry, %for1.inc
+  %indvars.iv19 = phi i64 [ 0, %entry ], [ %indvars.iv.next20, %for1.inc ]
+  br label %for2
+
+for2:                                        ; preds = %for1.header, %for2
+  %indvars.iv = phi i64 [ 0, %for1.header ], [ %indvars.iv.next, %for2 ]
+  store i64 %indvars.iv, i64* %ptr, align 4
+  %indvars.iv.next = add nuw nsw i64 %indvars.iv, 1
+  %exitcond = icmp ne i64 %indvars.iv.next, 1024
+  br i1 %exitcond, label %for2, label %for1.inc
+
+for1.inc:
+  %indvars.iv.next20 = add nuw nsw i64 %indvars.iv19, 1
+  %exitcond21 = icmp ne i64 %indvars.iv.next20, 1024
+  br i1 %exitcond21, label %for1.header, label %exit
+
+exit:                                 ; preds = %for1.inc
+  ret i32 0
+}
+
+
+; Check stats, we interchanged 1 out of 3 loops.
+; STATS: 1 loop-interchange - Number of loops interchanged