[Mlir-commits] [mlir] [mlir][func]-Add deduplicate funcOp arguments transform (PR #158266)

[Mehdi Amini]

================
@@ -37,12 +38,62 @@ func::replaceFuncWithNewOrder(RewriterBase &rewriter, func::FuncOp funcOp,
   ArrayRef<Type> origOutputTypes = funcOp.getFunctionType().getResults();
   SmallVector<Type> newInputTypes, newOutputTypes;
   SmallVector<Location> locs;
-  for (unsigned int idx : newArgsOrder) {
-    newInputTypes.push_back(origInputTypes[idx]);
-    locs.push_back(funcOp.getArgument(newArgsOrder[idx]).getLoc());
+
+  // We may have some duplicate arguments in the old function, i.e.
+  // in the mapping `newArgIdxToOldArgIdxs` for some new argument index
+  // there may be multiple old argument indices.
+  unsigned numOfNewArgs = 0;
+  auto maxNewArgIdx = llvm::max_element(oldArgToNewArg);
+  if (maxNewArgIdx != oldArgToNewArg.end())
+    numOfNewArgs = *maxNewArgIdx + 1;
----------------
joker-eph wrote:

What is this condition guarding? Only if the input is empty? If so, this seems more direct:

```suggestion
  if (! oldArgToNewArg.empty()
   numOfNewArgs = 1 + *llvm::max_element(oldArgToNewArg);
```

https://github.com/llvm/llvm-project/pull/158266