[LoopInterchange] Fix depends() check parameters

Author: ShivaChen

llvm/lib/Transforms/Scalar/LoopInterchange.cpp

@@ -115,8 +115,8 @@ static bool populateDependencyMatrix(CharMatrix &DepMatrix, unsigned Level,
   for (I = MemInstr.begin(), IE = MemInstr.end(); I != IE; ++I) {
     for (J = I + 1, JE = MemInstr.end(); J != JE; ++J) {
       std::vector<char> Dep;
-      Instruction *Src = cast<Instruction>(*I);
-      Instruction *Dst = cast<Instruction>(*J);
+      Instruction *Src = cast<Instruction>(*J);
+      Instruction *Dst = cast<Instruction>(*I);
       // Ignore Input dependencies.
       if (isa<LoadInst>(Src) && isa<LoadInst>(Dst))
         continue;

llvm/test/Transforms/LoopInterchange/interchange-s231.ll

@@ -10,11 +10,11 @@
 ;;      for (int j = 1; j < 256; j++)
 ;;        aa[j][i] = aa[j - 1][i] + bb[j][i];
 
-; CHECK: Found anti dependency between Src and Dst
-; CHECK:  Src:  %1 = load float, ptr %arrayidx10, align 4
-; CHECK:  Dst:  store float %add, ptr %arrayidx18, align 4
+; CHECK: Found flow dependency between Src and Dst
+; CHECK:  Src:  store float %add, ptr %arrayidx18, align 4
+; CHECK:  Dst:  %1 = load float, ptr %arrayidx10, align 4
 ; CHECK: Processing InnerLoopId = 2 and OuterLoopId = 1
-; CHECK: Not interchanging loops. Cannot prove legality.
+; CHECK: Loops interchanged.
 
 define float @s231() {
 entry: