[Mlir-commits] [flang] [mlir] [flang] Added OperationMoveOpInterface for controlling LICM. (PR #175108)

[Matthias Springer]

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@@ -0,0 +1,75 @@
+//===-- FIROperationMoveOpInterface.td ---------------------*- tablegen -*-===//
+//
+// 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/Interfaces.td"
+
+def OperationMoveOpInterface : OpInterface<"OperationMoveOpInterface"> {
+  let description = [{
+    Provides methods to control movement of operations during transformations.
+    For example, some LoopLikeOpInterface operations may disallow
+    hoisting speculatable operations (e.g. even Pure ones) under some
+    conditions. Operations may control when the hoisting
+    (or rather a general movement) is allowed by implementing this interface.
+  }];
+  let cppNamespace = "::fir";
+  let verify = [{ return detail::verifyOperationMoveOpInterface($_op); }];
+  let methods =
+      [InterfaceMethod<
+           /*desc=*/[{
+        Returns true if it is allowed to move the given 'candidate'
+        operation from the 'descendant' operation into this operation.
+        If 'candidate' is nullptr, then the caller is querying whether
+        any operation from any descendant can be moved into this operation.
+
+        The implementations of OperationMoveOpInterface should not provide
+        implementation of this method, in general. The default implementation
+        applies some verification and relays to canMoveFromDescendantImpl()
+        method, which the implementations must provide.
+      }],
+           /*returnType=*/"bool",
+           /*methodName=*/"canMoveFromDescendant",
+           /*args=*/
+           (ins "::mlir::Operation *":$descendant,
+               "::mlir::Operation *":$candidate),
+           /*methodBody=*/[{}],
+           /*defaultImplementation=*/[{
+        return detail::canMoveFromDescendant($_op, descendant, candidate);
+      }]>,
+       InterfaceMethod<
+           /*desc=*/"",
+           /*returnType=*/"bool",
+           /*methodName=*/"canMoveFromDescendantImpl",
+           /*args=*/
+           (ins "::mlir::Operation *":$descendant,
+               "::mlir::Operation *":$candidate)>,
+       InterfaceMethod<
+           /*desc=*/[{
+        Returns true if it is allowed to move the given 'candidate'
+        operation out of this operation. If 'candidate' is nullptr,
+        then the caller is querying whether any operation can be moved
+        out of this operation.
+
+        The implementations of OperationMoveOpInterface should not provide
+        implementation of this method, in general. The default implementation
+        applies some verification and relays to canMoveOutOfImpl() method,
+        which the implementations must provide.
+      }],
+           /*returnType=*/"bool",
+           /*methodName=*/"canMoveOutOf",
+           /*args=*/(ins "::mlir::Operation *":$candidate),
+           /*methodBody=*/[{}],
+           /*defaultImplementation=*/[{
+        return detail::canMoveOutOf($_op, candidate);
+      }]>,
+       InterfaceMethod<
+           /*desc=*/"Implementation of canMoveOutOf() for concrete operation",
+           /*returnType=*/"bool",
+           /*methodName=*/"canMoveOutOfImpl",
----------------
matthias-springer wrote:

Why are there two interface methods `canMoveOutOf` and `canMoveOutOfImpl`? That's a bit unusual.

https://github.com/llvm/llvm-project/pull/175108