--- /dev/null
+//===- PatternBenefit.cpp - RewritePattern benefit unit tests -------------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+
+#include "mlir/IR/PatternMatch.h"
+#include "mlir/Rewrite/PatternApplicator.h"
+#include "gtest/gtest.h"
+
+using namespace mlir;
+
+namespace {
+TEST(PatternBenefitTest, BenefitOrder) {
+ // There was a bug which caused low-benefit op-specific patterns to never be
+ // called in presence of high-benefit op-agnostic pattern
+
+ MLIRContext context;
+
+ OpBuilder builder(&context);
+ auto module = ModuleOp::create(builder.getUnknownLoc());
+
+ struct Pattern1 : public OpRewritePattern<ModuleOp> {
+ Pattern1(mlir::MLIRContext *context, bool *called)
+ : OpRewritePattern<ModuleOp>(context, /*benefit*/ 1), called(called) {}
+
+ mlir::LogicalResult
+ matchAndRewrite(ModuleOp /*op*/,
+ mlir::PatternRewriter & /*rewriter*/) const override {
+ *called = true;
+ return failure();
+ }
+
+ private:
+ bool *called;
+ };
+
+ struct Pattern2 : public RewritePattern {
+ Pattern2(bool *called)
+ : RewritePattern(/*benefit*/ 2, MatchAnyOpTypeTag{}), called(called) {}
+
+ mlir::LogicalResult
+ matchAndRewrite(Operation * /*op*/,
+ mlir::PatternRewriter & /*rewriter*/) const override {
+ *called = true;
+ return failure();
+ }
+
+ private:
+ bool *called;
+ };
+
+ OwningRewritePatternList patterns;
+
+ bool called1 = false;
+ bool called2 = false;
+
+ patterns.insert<Pattern1>(&context, &called1);
+ patterns.insert<Pattern2>(&called2);
+
+ FrozenRewritePatternList frozenPatterns(std::move(patterns));
+ PatternApplicator pa(frozenPatterns);
+ pa.applyDefaultCostModel();
+
+ class MyPatternRewriter : public PatternRewriter {
+ public:
+ MyPatternRewriter(MLIRContext *ctx) : PatternRewriter(ctx) {}
+ };
+
+ MyPatternRewriter rewriter(&context);
+ (void)pa.matchAndRewrite(module, rewriter);
+
+ EXPECT_TRUE(called1);
+ EXPECT_TRUE(called2);
+}
+} // namespace