clang-tools 8.0.0

SIMDIntrinsicsCheck.cpp
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1 //===--- SIMDIntrinsicsCheck.cpp - clang-tidy------------------------------===//
2 //
3 // The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9
10 #include "SIMDIntrinsicsCheck.h"
11 #include "clang/AST/ASTContext.h"
12 #include "clang/ASTMatchers/ASTMatchFinder.h"
13 #include "llvm/ADT/StringMap.h"
14 #include "llvm/ADT/Triple.h"
15 #include "llvm/Support/Regex.h"
16
17 using namespace clang::ast_matchers;
18
19 namespace clang {
20 namespace tidy {
21 namespace portability {
22
23 namespace {
24
25 // If the callee has parameter of VectorType or pointer to VectorType,
26 // or the return type is VectorType, we consider it a vector function
27 // and a candidate for checking.
28 AST_MATCHER(FunctionDecl, isVectorFunction) {
29 bool IsVector = Node.getReturnType()->isVectorType();
30 for (const ParmVarDecl *Parm : Node.parameters()) {
31 QualType Type = Parm->getType();
32 if (Type->isPointerType())
33 Type = Type->getPointeeType();
34 if (Type->isVectorType())
35 IsVector = true;
36 }
37 return IsVector;
38 }
39
40 } // namespace
41
42 static StringRef TrySuggestPPC(StringRef Name) {
43 if (!Name.consume_front("vec_"))
44 return {};
45
46 static const llvm::StringMap<StringRef> Mapping{
47 // [simd.alg]
48 {"max", "$std::max"},
49 {"min", "$std::min"},
50
51 // [simd.binary]
52 {"add", "operator+ on $simd objects"},
53 {"sub", "operator- on $simd objects"},
54 {"mul", "operator* on $simd objects"},
55 };
56
57 auto It = Mapping.find(Name);
58 if (It != Mapping.end())
59 return It->second;
60 return {};
61 }
62
63 static StringRef TrySuggestX86(StringRef Name) {
64 if (!(Name.consume_front("_mm_") || Name.consume_front("_mm256_") ||
65 Name.consume_front("_mm512_")))
66 return {};
67
68 // [simd.alg]
69 if (Name.startswith("max_"))
70 return "$simd::max";
71 if (Name.startswith("min_"))
72 return "$simd::min";
73
74 // [simd.binary]
75 if (Name.startswith("add_"))
76 return "operator+ on $simd objects";
77 if (Name.startswith("sub_"))
78 return "operator- on $simd objects";
79 if (Name.startswith("mul_"))
80 return "operator* on $simd objects";
81
82 return {};
83 }
84
85 SIMDIntrinsicsCheck::SIMDIntrinsicsCheck(StringRef Name,
86 ClangTidyContext *Context)
87 : ClangTidyCheck(Name, Context), Std(Options.get("Std", "")),
88 Suggest(Options.get("Suggest", 0) != 0) {}
89
90 void SIMDIntrinsicsCheck::storeOptions(ClangTidyOptions::OptionMap &Opts) {
91 Options.store(Opts, "Std", "");
92 Options.store(Opts, "Suggest", 0);
93 }
94
95 void SIMDIntrinsicsCheck::registerMatchers(MatchFinder *Finder) {
96 if (!getLangOpts().CPlusPlus11)
97 return;
98 // If Std is not specified, infer it from the language options.
99 // libcxx implementation backports it to C++11 std::experimental::simd.
100 if (Std.empty())
101 Std = getLangOpts().CPlusPlus2a ? "std" : "std::experimental";
102
103 Finder->addMatcher(callExpr(callee(functionDecl(
104 matchesName("^::(_mm_|_mm256_|_mm512_|vec_)"),
105 isVectorFunction())),
106 unless(isExpansionInSystemHeader()))
107 .bind("call"),
108 this);
109 }
110
111 void SIMDIntrinsicsCheck::check(const MatchFinder::MatchResult &Result) {
112 const auto *Call = Result.Nodes.getNodeAs<CallExpr>("call");
113 assert(Call != nullptr);
114 const FunctionDecl *Callee = Call->getDirectCallee();
115 if (!Callee)
116 return;
117
118 StringRef Old = Callee->getName();
119 StringRef New;
120 llvm::Triple::ArchType Arch =
121 Result.Context->getTargetInfo().getTriple().getArch();
122
123 // We warn or suggest if this SIMD intrinsic function has a std::simd
124 // replacement.
125 switch (Arch) {
126 default:
127 break;
128 case llvm::Triple::ppc:
129 case llvm::Triple::ppc64:
130 case llvm::Triple::ppc64le:
131 New = TrySuggestPPC(Old);
132 break;
133 case llvm::Triple::x86:
134 case llvm::Triple::x86_64:
135 New = TrySuggestX86(Old);
136 break;
137 }
138
139 // We have found a std::simd replacement.
140 if (!New.empty()) {
141 std::string Message;
142 // If Suggest is true, give a P0214 alternative, otherwise point it out it
143 // is non-portable.
144 if (Suggest) {
145 Message = (Twine("'") + Old + "' can be replaced by " + New).str();
146 Message = llvm::Regex("\\$std").sub(Std, Message);
147 Message =
148 llvm::Regex("\\$simd").sub((Std.str() + "::simd").str(), Message);
149 } else {
150 Message = (Twine("'") + Old + "' is a non-portable " +
151 llvm::Triple::getArchTypeName(Arch) + " intrinsic function")
152 .str();
153 }
154 diag(Call->getExprLoc(), Message);
155 }
156 }
157
158 } // namespace portability
159 } // namespace tidy
160 } // namespace clang
clang::ast_matchers
Definition: AbseilMatcher.h:15
clang::tidy::matchers::AST_MATCHER
AST_MATCHER(BinaryOperator, isAssignmentOperator)
Definition: Matchers.h:20
clang::tidy::OptionsView::store
void store(ClangTidyOptions::OptionMap &Options, StringRef LocalName, StringRef Value) const
Stores an option with the check-local name LocalName with string value Value to Options.
Definition: ClangTidy.cpp:473
clang::tidy::ClangTidyCheck::getLangOpts
LangOptions getLangOpts() const
Returns the language options from the context.
Definition: ClangTidy.h:187
clang::tidy::modernize::Message
static const StringRef Message
Definition: UseTransparentFunctorsCheck.cpp:71
clang::tidy::ClangTidyCheck
Base class for all clang-tidy checks.
Definition: ClangTidy.h:127
clang::tidy::ClangTidyCheck::Options
OptionsView Options
Definition: ClangTidy.h:183
SIMDIntrinsicsCheck.h
clang::tidy::portability::TrySuggestX86
static StringRef TrySuggestX86(StringRef Name)
Definition: SIMDIntrinsicsCheck.cpp:63
Name
static constexpr llvm::StringLiteral Name
Definition: UppercaseLiteralSuffixCheck.cpp:28
clang::tidy::ClangTidyOptions::OptionMap
std::map< std::string, std::string > OptionMap
Definition: ClangTidyOptions.h:98
Result
llvm::Optional< llvm::Expected< tooling::AtomicChanges > > Result
Definition: ClangdServer.cpp:60
clang::tidy::portability::SIMDIntrinsicsCheck::registerMatchers
void registerMatchers(ast_matchers::MatchFinder *Finder) override
Override this to register AST matchers with Finder.
Definition: SIMDIntrinsicsCheck.cpp:95
clang::tidy::portability::TrySuggestPPC
static StringRef TrySuggestPPC(StringRef Name)
Definition: SIMDIntrinsicsCheck.cpp:42
clang::tidy::portability::SIMDIntrinsicsCheck::check
void check(const ast_matchers::MatchFinder::MatchResult &Result) override
ClangTidyChecks that register ASTMatchers should do the actual work in here.
Definition: SIMDIntrinsicsCheck.cpp:111
clang
===– Representation.cpp - ClangDoc Representation --------—*- C++ -*-===//
Definition: ChangeNamespace.cpp:18
clang::tidy::ClangTidyContext
Every ClangTidyCheck reports errors through a DiagnosticsEngine provided by this context.
Definition: ClangTidyDiagnosticConsumer.h:100
clang::tidy::portability::SIMDIntrinsicsCheck::storeOptions
void storeOptions(ClangTidyOptions::OptionMap &Opts) override
Should store all options supported by this check with their current values or default values for opti...
Definition: SIMDIntrinsicsCheck.cpp:90
clang::tidy::ClangTidyCheck::diag
DiagnosticBuilder diag(SourceLocation Loc, StringRef Description, DiagnosticIDs::Level Level=DiagnosticIDs::Warning)
Add a diagnostic with the check&#39;s name.
Definition: ClangTidy.cpp:438