Add Operation::moveAfter

This revision introduces an Operation::moveAfter mirroring
Operation::moveBefore to move an operation after another
existing operation or an iterator in a specified block.

Resolves https://bugs.llvm.org/show_bug.cgi?id=45799

Differential Revision: https://reviews.llvm.org/D79640

mlir/include/mlir/IR/Operation.h

@@ -185,6 +185,15 @@ public:
   /// `iterator` in the specified block.
   void moveBefore(Block *block, llvm::iplist<Operation>::iterator iterator);
 
+  /// Unlink this operation from its current block and insert it right after
+  /// `existingOp` which may be in the same or another block in the same
+  /// function.
+  void moveAfter(Operation *existingOp);
+
+  /// Unlink this operation from its current block and insert it right after
+  /// `iterator` in the specified block.
+  void moveAfter(Block *block, llvm::iplist<Operation>::iterator iterator);
+
   /// Given an operation 'other' that is within the same parent block, return
   /// whether the current operation is before 'other' in the operation list
   /// of the parent block.

mlir/lib/IR/Operation.cpp

@@ -492,6 +492,20 @@ void Operation::moveBefore(Block *block,
                                 getIterator());
 }
 
+/// Unlink this operation from its current block and insert it right after
+/// `existingOp` which may be in the same or another block in the same function.
+void Operation::moveAfter(Operation *existingOp) {
+  moveAfter(existingOp->getBlock(), existingOp->getIterator());
+}
+
+/// Unlink this operation from its current block and insert it right after
+/// `iterator` in the specified block.
+void Operation::moveAfter(Block *block,
+                          llvm::iplist<Operation>::iterator iterator) {
+  assert(iterator != block->end() && "cannot move after end of block");
+  moveBefore(&*std::next(iterator));
+}
+
 /// This drops all operand uses from this operation, which is an essential
 /// step in breaking cyclic dependences between references when they are to
 /// be deleted.