[llvm] [LoopInterchange] Modernize loops (NFC) (PR #146105)

[Ryotaro Kasuga via llvm-commits]

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@@ -1220,8 +1217,8 @@ LoopInterchangeProfitability::isProfitablePerInstrOrderCost() {
 
 /// Return true if we can vectorize the loop specified by \p LoopId.
 static bool canVectorize(const CharMatrix &DepMatrix, unsigned LoopId) {
-  for (unsigned I = 0; I != DepMatrix.size(); I++) {
-    char Dir = DepMatrix[I][LoopId];
+  for (auto Dep : DepMatrix) {
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kasuga-fj wrote:

```suggestion
  for (const auto &Dep : DepMatrix) {
```

https://github.com/llvm/llvm-project/pull/146105