1// Copyright (c) 2018 Google LLC.
2//
3// Licensed under the Apache License, Version 2.0 (the "License");
4// you may not use this file except in compliance with the License.
5// You may obtain a copy of the License at
6//
7// http://www.apache.org/licenses/LICENSE-2.0
8//
9// Unless required by applicable law or agreed to in writing, software
10// distributed under the License is distributed on an "AS IS" BASIS,
11// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12// See the License for the specific language governing permissions and
13// limitations under the License.
14
15#ifndef SOURCE_OPT_LOOP_UNSWITCH_PASS_H_
16#define SOURCE_OPT_LOOP_UNSWITCH_PASS_H_
17
18#include "source/opt/loop_descriptor.h"
19#include "source/opt/pass.h"
20
21namespace spvtools {
22namespace opt {
23
24// Implements the loop unswitch optimization.
25// The loop unswitch hoists invariant "if" statements if the conditions are
26// constant within the loop and clones the loop for each branch.
27class LoopUnswitchPass : public Pass {
28 public:
29 const char* name() const override { return "loop-unswitch"; }
30
31 // Processes the given |module|. Returns Status::Failure if errors occur when
32 // processing. Returns the corresponding Status::Success if processing is
33 // succesful to indicate whether changes have been made to the modue.
34 Pass::Status Process() override;
35
36 private:
37 bool ProcessFunction(Function* f);
38};
39
40} // namespace opt
41} // namespace spvtools
42
43#endif // SOURCE_OPT_LOOP_UNSWITCH_PASS_H_
44