diff --git a/paddle/fluid/framework/block_desc.cc b/paddle/fluid/framework/block_desc.cc index 3693bc25d81a8309df1a6ddf3d9b08d484596ea9..fbe08349c37c4fde115ceea954ba2b84880088d7 100644 --- a/paddle/fluid/framework/block_desc.cc +++ b/paddle/fluid/framework/block_desc.cc @@ -147,15 +147,52 @@ void BlockDesc::RemoveOp(size_t s, size_t e) { if (ops_.begin() + s == ops_.end() || ops_.begin() + e == ops_.end()) { return; } + auto get_vars = [](std::deque>::iterator &op, + std::vector &v) { + auto in_names = (*op)->InputArgumentNames(); + v.insert(v.end(), in_names.begin(), in_names.end()); + auto out_names = (*op)->OutputArgumentNames(); + v.insert(v.end(), out_names.begin(), out_names.end()); + std::sort(v.begin(), v.end()); + auto last = std::unique(v.begin(), v.end()); + v.erase(last, v.end()); + }; need_update_ = true; - for (auto it = ops_.begin() + s; it != ops_.begin() + e; it++) { - auto names = (*it)->InputArgumentNames(); - for (auto n : names) { - // TODO(typhoonzero): delete vars if no other op use it. - VLOG(3) << "deleting var " << n; + + for (size_t i = s; i < e; i++) { + // since remove op one by one, every time remove the first op. + auto op = ops_.begin() + s; + + // collect input and output variables from current delete op + std::vector cur_vars; + get_vars(op, cur_vars); + + // remove current op + ops_.erase(ops_.begin() + s); + + // collect input and output variables from other ops + std::vector other_vars; + for (auto it = ops_.begin(); it != ops_.end(); it++) { + get_vars(it, other_vars); + } + + // variables should be deleted + std::vector delete_vars; + // delete_vars = cur_vars - cur_vars ^ other_input_vars + std::set_difference(cur_vars.begin(), cur_vars.end(), other_vars.begin(), + other_vars.end(), + std::inserter(delete_vars, delete_vars.end())); + // remove variables + for (size_t i = 0; i < delete_vars.size(); i++) { + auto name = delete_vars[i]; + auto it = vars_.find(name); + PADDLE_ENFORCE(it != vars_.end(), + "%s is not in variable list, it should not be deleted", + name); + vars_.erase(it); + VLOG(3) << "deleting variable " << name; } } - ops_.erase(ops_.begin() + s, ops_.begin() + e); } std::vector BlockDesc::AllOps() const { diff --git a/paddle/fluid/framework/block_desc.h b/paddle/fluid/framework/block_desc.h index 185f018ac1b5863e0ee86fdaa17df1ccbc6e030e..468423e0e8e7b8c9ebc14b7568c9c3bd21645ea7 100644 --- a/paddle/fluid/framework/block_desc.h +++ b/paddle/fluid/framework/block_desc.h @@ -89,6 +89,11 @@ class BlockDesc { OpDesc *InsertOp(size_t index); + /* + * Remove Op and its input/output variables. + * Note that for either input or ouput variable, if it is also an input or + * output variable of other ops, we should remain it. + */ void RemoveOp(size_t s, size_t e); std::vector AllOps() const; diff --git a/python/paddle/fluid/tests/unittests/test_protobuf_descs.py b/python/paddle/fluid/tests/unittests/test_protobuf_descs.py index 309ea2b9b7ede442da3ac897ce8d1a4b9aa68233..da85786d0c085a4e97d9ac272feed251296ad52d 100644 --- a/python/paddle/fluid/tests/unittests/test_protobuf_descs.py +++ b/python/paddle/fluid/tests/unittests/test_protobuf_descs.py @@ -186,6 +186,34 @@ class TestBlockDesc(unittest.TestCase): all_ops.append(block.op(idx)) self.assertEqual(all_ops, [op0, op1, op2]) + def test_remove_op(self): + prog = core.ProgramDesc() + self.assertIsNotNone(prog) + block = prog.block(0) + self.assertIsNotNone(block) + op1 = block.append_op() + op2 = block.append_op() + var1 = block.var("var1") + var2 = block.var("var2") + var3 = block.var("var3") + var4 = block.var("var4") + var5 = block.var("var5") + op1.set_input("X", ["var1", "var2"]) + op1.set_output("Y", ["var3", "var4"]) + op2.set_input("X", ["var1"]) + op2.set_output("Y", ["var4", "var5"]) + + # remove op1, its input var2 and output var3 will be removed at the same time, + # but its input var1 and output var4 will not be removed since they are used for op2. + block.remove_op(0, 1) + + all_ops = [] + for idx in xrange(0, block.op_size()): + all_ops.append(block.op(idx)) + self.assertEqual(all_ops, [op2]) + all_vars = block.all_vars() + self.assertEqual(set(all_vars), {var1, var4, var5}) + if __name__ == '__main__': unittest.main()