[Mlir-commits] [mlir] [mlir][pass] Add composite pass utility (PR #87166)

[Mehdi Amini]

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@@ -0,0 +1,81 @@
+//===- CompositePass.cpp - Composite pass code ----------------------------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+//
+// CompositePass allows to run set of passes until fixed point is reached.
+//
+//===----------------------------------------------------------------------===//
+
+#include "mlir/Transforms/Passes.h"
+
+#include "mlir/Pass/Pass.h"
+#include "mlir/Pass/PassManager.h"
+
+using namespace mlir;
+
+namespace {
+struct CompositePass final
+    : public PassWrapper<CompositePass, OperationPass<void>> {
+  MLIR_DEFINE_EXPLICIT_INTERNAL_INLINE_TYPE_ID(CompositePass)
+
+  CompositePass(std::string name_, std::string argument_,
+                llvm::function_ref<void(OpPassManager &)> populateFunc,
+                unsigned maxIterations)
+      : name(std::move(name_)), argument(std::move(argument_)),
+        dynamicPM(std::make_shared<OpPassManager>()), maxIters(maxIterations) {
+    populateFunc(*dynamicPM);
+  }
+
+  void getDependentDialects(DialectRegistry &registry) const override {
+    dynamicPM->getDependentDialects(registry);
+  }
+
+  void runOnOperation() override {
+    auto op = getOperation();
+    OperationFingerPrint fp(op);
+
+    unsigned currentIter = 0;
+    while (true) {
+      if (failed(runPipeline(*dynamicPM, op)))
+        return signalPassFailure();
+
+      if (currentIter++ >= maxIters) {
+        op->emitWarning("Composite pass \"" + llvm::Twine(name) +
+                        "\"+ didn't converge in " + llvm::Twine(maxIters) +
+                        " iterations");
+        break;
+      }
+
+      OperationFingerPrint newFp(op);
+      if (newFp == fp)
+        break;
+
+      fp = newFp;
+    }
+  }
+
+protected:
+  llvm::StringRef getName() const override { return name; }
+
+  llvm::StringRef getArgument() const override { return argument; }
+
+private:
+  std::string name;
+  std::string argument;
+  std::shared_ptr<OpPassManager> dynamicPM;
+  unsigned maxIters;
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joker-eph wrote:

Please make sure that this can be serialized/deserialized entirely, so that we can exercise this with `mlir-opt` and ensure this works with `mlir-reproducers`

This can then be registered with all the other transform (and so defined in TableGen)

https://github.com/llvm/llvm-project/pull/87166