[llvm] [mlir] [mlir] Add PDL C & Python usage (PR #94714)

[Maksim Levental via llvm-commits]

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@@ -0,0 +1,60 @@
+//===-- mlir-c/Rewrite.h - Helpers for C API to Rewrites ----------*- C -*-===//
+//
+// 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 header declares the registration and creation method for
+// rewrite patterns.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef MLIR_C_REWRITE_H
+#define MLIR_C_REWRITE_H
+
+#include "mlir-c/IR.h"
+#include "mlir-c/Support.h"
+#include "mlir/Config/mlir-config.h"
+
+//===----------------------------------------------------------------------===//
+/// Opaque type declarations (see mlir-c/IR.h for more details).
+//===----------------------------------------------------------------------===//
+
+#define DEFINE_C_API_STRUCT(name, storage)                                     \
+  struct name {                                                                \
+    storage *ptr;                                                              \
+  };                                                                           \
+  typedef struct name name
+
+DEFINE_C_API_STRUCT(MlirFrozenRewritePatternSet, void);
+DEFINE_C_API_STRUCT(MlirGreedyRewriteDriverConfig, void);
+DEFINE_C_API_STRUCT(MlirRewritePatternSet, void);
+
+MLIR_CAPI_EXPORTED MlirFrozenRewritePatternSet
+mlirFreezeRewritePattern(MlirRewritePatternSet op);
+
+MLIR_CAPI_EXPORTED void
+mlirFrozenRewritePatternSetDestroy(MlirFrozenRewritePatternSet op);
+
+MLIR_CAPI_EXPORTED MlirLogicalResult mlirApplyPatternsAndFoldGreedily(
+    MlirModule op, MlirFrozenRewritePatternSet patterns,
+    MlirGreedyRewriteDriverConfig);
+
+#if MLIR_ENABLE_PDL_IN_PATTERNMATCH
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makslevental wrote:

TIL

https://github.com/llvm/llvm-project/pull/94714