[Mlir-commits] [mlir] [MLIR][Transforms] add eliminate-explicit-rounding pass (PR #93443)

[Mehdi Amini]

================
@@ -0,0 +1,62 @@
+//===- EliminateExplicitRounding.cpp - Remove intermediate extf/truncf pairs
+//-===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+//
+// This file implements removing intermediate extf/truncf pairs inserted from
+// type conversion.
+//
+//===----------------------------------------------------------------------===//
+#include "mlir/Dialect/Arith/Transforms/Passes.h"
+
+#include "mlir/Dialect/Arith/IR/Arith.h"
+#include "mlir/IR/PatternMatch.h"
+#include "mlir/IR/TypeUtilities.h"
+#include "mlir/Transforms/GreedyPatternRewriteDriver.h"
+
+namespace mlir {
+namespace arith {
+#define GEN_PASS_DEF_ARITHELIMINATEEXPLICITROUNDING
+#include "mlir/Dialect/Arith/Transforms/Passes.h.inc"
+} // namespace arith
+} // namespace mlir
+
+using namespace mlir;
+
+namespace {
+
+struct EliminateExplicitRounding final
+    : arith::impl::ArithEliminateExplicitRoundingBase<
+          EliminateExplicitRounding> {
+  using ArithEliminateExplicitRoundingBase::ArithEliminateExplicitRoundingBase;
+  void runOnOperation() override {
+    getOperation()->walk([&](arith::ExtFOp extFOp) {
+      // Check whether match `truncF->extF` pair.
+      auto truncFOp = extFOp.getOperand().getDefiningOp<arith::TruncFOp>();
+      if (truncFOp) {
----------------
joker-eph wrote:

Nit, we prefer early return, it reduces indentation and simplify the control flow.

```suggestion
      if (truncFOp) return;
```

https://github.com/llvm/llvm-project/pull/93443