1 // Copyright 2021 The Tint Authors.
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 #include "src/transform/for_loop_to_loop.h"
16
17 #include "src/ast/break_statement.h"
18 #include "src/program_builder.h"
19
20 TINT_INSTANTIATE_TYPEINFO(tint::transform::ForLoopToLoop);
21
22 namespace tint {
23 namespace transform {
24 ForLoopToLoop::ForLoopToLoop() = default;
25
26 ForLoopToLoop::~ForLoopToLoop() = default;
27
Run(CloneContext & ctx,const DataMap &,DataMap &)28 void ForLoopToLoop::Run(CloneContext& ctx, const DataMap&, DataMap&) {
29 ctx.ReplaceAll(
30 [&](const ast::ForLoopStatement* for_loop) -> const ast::Statement* {
31 ast::StatementList stmts;
32 if (auto* cond = for_loop->condition) {
33 // !condition
34 auto* not_cond = ctx.dst->create<ast::UnaryOpExpression>(
35 ast::UnaryOp::kNot, ctx.Clone(cond));
36
37 // { break; }
38 auto* break_body =
39 ctx.dst->Block(ctx.dst->create<ast::BreakStatement>());
40
41 // if (!condition) { break; }
42 stmts.emplace_back(ctx.dst->If(not_cond, break_body));
43 }
44 for (auto* stmt : for_loop->body->statements) {
45 stmts.emplace_back(ctx.Clone(stmt));
46 }
47
48 const ast::BlockStatement* continuing = nullptr;
49 if (auto* cont = for_loop->continuing) {
50 continuing = ctx.dst->Block(ctx.Clone(cont));
51 }
52
53 auto* body = ctx.dst->Block(stmts);
54 auto* loop = ctx.dst->create<ast::LoopStatement>(body, continuing);
55
56 if (auto* init = for_loop->initializer) {
57 return ctx.dst->Block(ctx.Clone(init), loop);
58 }
59
60 return loop;
61 });
62
63 ctx.Clone();
64 }
65
66 } // namespace transform
67 } // namespace tint
68