xref: /llvm-project/flang/lib/Semantics/check-coarray.cpp (revision 1f8790050b0e99e7b46cc69518aa84f46f50738e)
1 //===-- lib/Semantics/check-coarray.cpp -----------------------------------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 
9 #include "check-coarray.h"
10 #include "flang/Common/indirection.h"
11 #include "flang/Evaluate/expression.h"
12 #include "flang/Parser/message.h"
13 #include "flang/Parser/parse-tree.h"
14 #include "flang/Parser/tools.h"
15 #include "flang/Semantics/expression.h"
16 #include "flang/Semantics/tools.h"
17 
18 namespace Fortran::semantics {
19 
20 class CriticalBodyEnforce {
21 public:
22   CriticalBodyEnforce(
23       SemanticsContext &context, parser::CharBlock criticalSourcePosition)
24       : context_{context}, criticalSourcePosition_{criticalSourcePosition} {}
25   std::set<parser::Label> labels() { return labels_; }
26   template <typename T> bool Pre(const T &) { return true; }
27   template <typename T> void Post(const T &) {}
28 
29   template <typename T> bool Pre(const parser::Statement<T> &statement) {
30     currentStatementSourcePosition_ = statement.source;
31     if (statement.label.has_value()) {
32       labels_.insert(*statement.label);
33     }
34     return true;
35   }
36 
37   // C1118
38   void Post(const parser::ReturnStmt &) {
39     context_
40         .Say(currentStatementSourcePosition_,
41             "RETURN statement is not allowed in a CRITICAL construct"_err_en_US)
42         .Attach(criticalSourcePosition_, GetEnclosingMsg());
43   }
44   void Post(const parser::ExecutableConstruct &construct) {
45     if (IsImageControlStmt(construct)) {
46       context_
47           .Say(currentStatementSourcePosition_,
48               "An image control statement is not allowed in a CRITICAL"
49               " construct"_err_en_US)
50           .Attach(criticalSourcePosition_, GetEnclosingMsg());
51     }
52   }
53 
54 private:
55   parser::MessageFixedText GetEnclosingMsg() {
56     return "Enclosing CRITICAL statement"_en_US;
57   }
58 
59   SemanticsContext &context_;
60   std::set<parser::Label> labels_;
61   parser::CharBlock currentStatementSourcePosition_;
62   parser::CharBlock criticalSourcePosition_;
63 };
64 
65 template <typename T>
66 static void CheckTeamType(SemanticsContext &context, const T &x) {
67   if (const auto *expr{GetExpr(x)}) {
68     if (!IsTeamType(evaluate::GetDerivedTypeSpec(expr->GetType()))) {
69       context.Say(parser::FindSourceLocation(x), // C1114
70           "Team value must be of type TEAM_TYPE from module ISO_FORTRAN_ENV"_err_en_US);
71     }
72   }
73 }
74 
75 void CoarrayChecker::Leave(const parser::ChangeTeamStmt &x) {
76   CheckNamesAreDistinct(std::get<std::list<parser::CoarrayAssociation>>(x.t));
77   CheckTeamType(context_, std::get<parser::TeamValue>(x.t));
78 }
79 
80 void CoarrayChecker::Leave(const parser::SyncTeamStmt &x) {
81   CheckTeamType(context_, std::get<parser::TeamValue>(x.t));
82 }
83 
84 void CoarrayChecker::Leave(const parser::ImageSelectorSpec &x) {
85   if (const auto *team{std::get_if<parser::TeamValue>(&x.u)}) {
86     CheckTeamType(context_, *team);
87   }
88 }
89 
90 void CoarrayChecker::Leave(const parser::FormTeamStmt &x) {
91   CheckTeamType(context_, std::get<parser::TeamVariable>(x.t));
92 }
93 
94 void CoarrayChecker::Enter(const parser::CriticalConstruct &x) {
95   auto &criticalStmt{std::get<parser::Statement<parser::CriticalStmt>>(x.t)};
96 
97   const parser::Block &block{std::get<parser::Block>(x.t)};
98   CriticalBodyEnforce criticalBodyEnforce{context_, criticalStmt.source};
99   parser::Walk(block, criticalBodyEnforce);
100 
101   // C1119
102   LabelEnforce criticalLabelEnforce{
103       context_, criticalBodyEnforce.labels(), criticalStmt.source, "CRITICAL"};
104   parser::Walk(block, criticalLabelEnforce);
105 }
106 
107 // Check that coarray names and selector names are all distinct.
108 void CoarrayChecker::CheckNamesAreDistinct(
109     const std::list<parser::CoarrayAssociation> &list) {
110   std::set<parser::CharBlock> names;
111   auto getPreviousUse{
112       [&](const parser::Name &name) -> const parser::CharBlock * {
113         auto pair{names.insert(name.source)};
114         return !pair.second ? &*pair.first : nullptr;
115       }};
116   for (const auto &assoc : list) {
117     const auto &decl{std::get<parser::CodimensionDecl>(assoc.t)};
118     const auto &selector{std::get<parser::Selector>(assoc.t)};
119     const auto &declName{std::get<parser::Name>(decl.t)};
120     if (context_.HasError(declName)) {
121       continue; // already reported an error about this name
122     }
123     if (auto *prev{getPreviousUse(declName)}) {
124       Say2(declName.source, // C1113
125           "Coarray '%s' was already used as a selector or coarray in this statement"_err_en_US,
126           *prev, "Previous use of '%s'"_en_US);
127     }
128     // ResolveNames verified the selector is a simple name
129     const parser::Name *name{parser::Unwrap<parser::Name>(selector)};
130     if (name) {
131       if (auto *prev{getPreviousUse(*name)}) {
132         Say2(name->source, // C1113, C1115
133             "Selector '%s' was already used as a selector or coarray in this statement"_err_en_US,
134             *prev, "Previous use of '%s'"_en_US);
135       }
136     }
137   }
138 }
139 
140 void CoarrayChecker::Say2(const parser::CharBlock &name1,
141     parser::MessageFixedText &&msg1, const parser::CharBlock &name2,
142     parser::MessageFixedText &&msg2) {
143   context_.Say(name1, std::move(msg1), name1)
144       .Attach(name2, std::move(msg2), name2);
145 }
146 } // namespace Fortran::semantics
147