[Mlir-commits] [mlir] [mlir] Add `SelectPass` (PR #130409)

[Mehdi Amini]

================
@@ -0,0 +1,133 @@
+//===- SelectPass.cpp - Select 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
+//
+//===----------------------------------------------------------------------===//
+//
+// SelectPass dynamically selects pass pipeline to run based on root op
+// attribute.
+//
+//===----------------------------------------------------------------------===//
+
+#include "mlir/Transforms/Passes.h"
+
+#include "mlir/Pass/Pass.h"
+#include "mlir/Pass/PassManager.h"
+
+namespace mlir {
+#define GEN_PASS_DEF_SELECTPASS
+#include "mlir/Transforms/Passes.h.inc"
+} // namespace mlir
+
+using namespace mlir;
+
+namespace {
+struct SelectPass final : public impl::SelectPassBase<SelectPass> {
+  using SelectPassBase::SelectPassBase;
+
+  SelectPass(
+      std::string name_, std::string selectCondName_,
+      ArrayRef<std::pair<StringRef, std::function<void(OpPassManager &)>>>
+          populateFuncs) {
+    name = std::move(name_);
+    selectCondName = std::move(selectCondName_);
+
+    SmallVector<std::string> selectVals;
+    SmallVector<std::string> selectPpls;
+    selectVals.reserve(populateFuncs.size());
+    selectPpls.reserve(populateFuncs.size());
+    selectPassManagers.reserve(populateFuncs.size());
+    for (auto &&[name, populate] : populateFuncs) {
+      selectVals.emplace_back(name);
+
+      auto &pm = selectPassManagers.emplace_back();
+      populate(pm);
+
+      llvm::raw_string_ostream os(selectPpls.emplace_back());
+      pm.printAsTextualPipeline(os);
+    }
+
+    selectValues = selectVals;
+    selectPipelines = selectPpls;
+  }
+
+  LogicalResult initializeOptions(
+      StringRef options,
+      function_ref<LogicalResult(const Twine &)> errorHandler) override {
+    if (failed(SelectPassBase::initializeOptions(options, errorHandler)))
+      return failure();
+
+    if (selectCondName.empty())
+      return errorHandler("select-cond-name is empty");
+
+    if (selectValues.size() != selectPipelines.size())
+      return errorHandler("values and pipelines size mismatch");
+
+    selectPassManagers.resize(selectPipelines.size());
+
+    for (auto &&[i, pipeline] : llvm::enumerate(selectPipelines)) {
+      if (failed(parsePassPipeline(pipeline, selectPassManagers[i])))
+        return errorHandler("failed to parse pipeline");
+    }
+
+    return success();
+  }
+
+  LogicalResult initialize(MLIRContext *context) override {
+    condAttrName = StringAttr::get(context, selectCondName);
+
+    selectAttrs.reserve(selectAttrs.size());
+    for (StringRef value : selectValues)
+      selectAttrs.emplace_back(StringAttr::get(context, value));
+
+    return success();
+  }
+
+  void getDependentDialects(DialectRegistry &registry) const override {
+    for (const OpPassManager &pipeline : selectPassManagers)
+      pipeline.getDependentDialects(registry);
+  }
+
+  void runOnOperation() override {
+    Operation *op = getOperation();
+    Attribute condAttrValue = op->getAttr(condAttrName);
+    if (!condAttrValue) {
+      op->emitError("condition attribute not present: ") << condAttrName;
+      return signalPassFailure();
+    }
+
+    for (auto &&[value, pm] :
+         llvm::zip_equal(selectAttrs, selectPassManagers)) {
+      if (value != condAttrValue)
+        continue;
+
+      if (failed(runPipeline(pm, op)))
+        return signalPassFailure();
+
+      return;
+    }
+
+    // TODO: add a default pipeline option.
+    op->emitError("unhandled condition value: ") << condAttrValue;
+    return signalPassFailure();
+  }
+
+protected:
+  StringRef getName() const override { return name; }
+
+private:
+  StringAttr condAttrName;
+  SmallVector<Attribute> selectAttrs;
+  SmallVector<OpPassManager> selectPassManagers;
----------------
joker-eph wrote:

It's not clear to me how is this handled with respect to serialization? Can you clarify please.

https://github.com/llvm/llvm-project/pull/130409