1 /**
2 * Copyright (c) 2021 Huawei Device Co., Ltd.
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
16 #include "asyncGeneratorFunctionBuilder.h"
17
18 #include "compiler/base/catchTable.h"
19 #include "compiler/core/pandagen.h"
20 #include "ir/base/scriptFunction.h"
21
22 namespace panda::es2panda::compiler {
Prepare(const ir::ScriptFunction * node) const23 void AsyncGeneratorFunctionBuilder::Prepare(const ir::ScriptFunction *node) const
24 {
25 VReg callee = FunctionReg(node);
26
27 pg_->CreateAsyncGeneratorObj(node, callee);
28 pg_->StoreAccumulator(node, funcObj_);
29 pg_->SuspendGenerator(node, funcObj_);
30 pg_->SetLabel(node, catchTable_->LabelSet().TryBegin());
31 }
32
CleanUp(const ir::ScriptFunction * node) const33 void AsyncGeneratorFunctionBuilder::CleanUp(const ir::ScriptFunction *node) const
34 {
35 const auto &labelSet = catchTable_->LabelSet();
36
37 pg_->SetLabel(node, labelSet.TryEnd());
38 pg_->SetLabel(node, labelSet.CatchBegin());
39 pg_->AsyncGeneratorReject(node, funcObj_);
40 pg_->EmitReturn(node);
41 pg_->SetLabel(node, labelSet.CatchEnd());
42 }
43
DirectReturn(const ir::AstNode * node) const44 void AsyncGeneratorFunctionBuilder::DirectReturn(const ir::AstNode *node) const
45 {
46 pg_->AsyncGeneratorResolve(node, funcObj_);
47 pg_->EmitReturn(node);
48 }
49
ImplicitReturn(const ir::AstNode * node) const50 void AsyncGeneratorFunctionBuilder::ImplicitReturn(const ir::AstNode *node) const
51 {
52 pg_->LoadConst(node, Constant::JS_UNDEFINED);
53 DirectReturn(node);
54 }
55
Yield(const ir::AstNode * node)56 void AsyncGeneratorFunctionBuilder::Yield(const ir::AstNode *node)
57 {
58 Await(node);
59
60 RegScope rs(pg_);
61 VReg completionType = pg_->AllocReg();
62 VReg completionValue = pg_->AllocReg();
63
64 AsyncYield(node, completionType, completionValue);
65
66 auto *notReturnCompletion = pg_->AllocLabel();
67 auto *normalCompletion = pg_->AllocLabel();
68 auto *notThrowCompletion = pg_->AllocLabel();
69
70 // 27.6.3.8.8.a. If resumptionValue.[[Type]] is not return
71 pg_->LoadAccumulatorInt(node, static_cast<int32_t>(ResumeMode::RETURN));
72 pg_->Condition(node, lexer::TokenType::PUNCTUATOR_EQUAL, completionType, notReturnCompletion);
73 // 27.6.3.8.8.b. Let awaited be Await(resumptionValue.[[Value]]).
74 pg_->LoadAccumulator(node, completionValue);
75 pg_->AsyncFunctionAwait(node, funcObj_);
76 SuspendResumeExecution(node, completionType, completionValue);
77
78 // 27.6.3.8.8.c. If awaited.[[Type]] is throw, return Completion(awaited).
79 pg_->LoadAccumulatorInt(node, static_cast<int32_t>(ResumeMode::THROW));
80
81 pg_->Condition(node, lexer::TokenType::PUNCTUATOR_EQUAL, completionType, normalCompletion);
82 pg_->LoadAccumulator(node, completionValue);
83 pg_->EmitThrow(node);
84
85 pg_->SetLabel(node, normalCompletion);
86 // 27.6.3.8.8.d. Assert: awaited.[[Type]] is normal.
87 // 27.6.3.8.8.e. Return Completion { [[Type]]: return, [[Value]]: awaited.[[Value]], [[Target]]: empty }.
88 pg_->ControlFlowChangeBreak();
89 pg_->LoadAccumulator(node, completionValue);
90 pg_->DirectReturn(node);
91
92 pg_->SetLabel(node, notReturnCompletion);
93 // 27.6.3.8.8.a. return Completion(resumptionValue).
94 pg_->LoadAccumulatorInt(node, static_cast<int32_t>(ResumeMode::THROW));
95 pg_->Condition(node, lexer::TokenType::PUNCTUATOR_EQUAL, completionType, notThrowCompletion);
96 pg_->LoadAccumulator(node, completionValue);
97 pg_->EmitThrow(node);
98 pg_->SetLabel(node, notThrowCompletion);
99 pg_->LoadAccumulator(node, completionValue);
100 }
101
GeneratorKind() const102 IteratorType AsyncGeneratorFunctionBuilder::GeneratorKind() const
103 {
104 return IteratorType::ASYNC;
105 }
106 } // namespace panda::es2panda::compiler
107