| //===--- DurationRewriter.cpp - clang-tidy --------------------------------===// |
| // |
| // The LLVM Compiler Infrastructure |
| // |
| // This file is distributed under the University of Illinois Open Source |
| // License. See LICENSE.TXT for details. |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #include "DurationRewriter.h" |
| #include "clang/Tooling/FixIt.h" |
| #include "llvm/ADT/IndexedMap.h" |
| |
| using namespace clang::ast_matchers; |
| |
| namespace clang { |
| namespace tidy { |
| namespace abseil { |
| |
| struct DurationScale2IndexFunctor { |
| using argument_type = DurationScale; |
| unsigned operator()(DurationScale Scale) const { |
| return static_cast<unsigned>(Scale); |
| } |
| }; |
| |
| /// Returns an integer if the fractional part of a `FloatingLiteral` is `0`. |
| static llvm::Optional<llvm::APSInt> |
| truncateIfIntegral(const FloatingLiteral &FloatLiteral) { |
| double Value = FloatLiteral.getValueAsApproximateDouble(); |
| if (std::fmod(Value, 1) == 0) { |
| if (Value >= static_cast<double>(1u << 31)) |
| return llvm::None; |
| |
| return llvm::APSInt::get(static_cast<int64_t>(Value)); |
| } |
| return llvm::None; |
| } |
| |
| /// Given a `Scale` return the inverse functions for it. |
| static const std::pair<llvm::StringRef, llvm::StringRef> & |
| getInverseForScale(DurationScale Scale) { |
| static const llvm::IndexedMap<std::pair<llvm::StringRef, llvm::StringRef>, |
| DurationScale2IndexFunctor> |
| InverseMap = []() { |
| // TODO: Revisit the immediately invoked lamba technique when |
| // IndexedMap gets an initializer list constructor. |
| llvm::IndexedMap<std::pair<llvm::StringRef, llvm::StringRef>, |
| DurationScale2IndexFunctor> |
| InverseMap; |
| InverseMap.resize(6); |
| InverseMap[DurationScale::Hours] = |
| std::make_pair("::absl::ToDoubleHours", "::absl::ToInt64Hours"); |
| InverseMap[DurationScale::Minutes] = |
| std::make_pair("::absl::ToDoubleMinutes", "::absl::ToInt64Minutes"); |
| InverseMap[DurationScale::Seconds] = |
| std::make_pair("::absl::ToDoubleSeconds", "::absl::ToInt64Seconds"); |
| InverseMap[DurationScale::Milliseconds] = std::make_pair( |
| "::absl::ToDoubleMilliseconds", "::absl::ToInt64Milliseconds"); |
| InverseMap[DurationScale::Microseconds] = std::make_pair( |
| "::absl::ToDoubleMicroseconds", "::absl::ToInt64Microseconds"); |
| InverseMap[DurationScale::Nanoseconds] = std::make_pair( |
| "::absl::ToDoubleNanoseconds", "::absl::ToInt64Nanoseconds"); |
| return InverseMap; |
| }(); |
| |
| return InverseMap[Scale]; |
| } |
| |
| /// If `Node` is a call to the inverse of `Scale`, return that inverse's |
| /// argument, otherwise None. |
| static llvm::Optional<std::string> |
| rewriteInverseDurationCall(const MatchFinder::MatchResult &Result, |
| DurationScale Scale, const Expr &Node) { |
| const std::pair<llvm::StringRef, llvm::StringRef> &InverseFunctions = |
| getInverseForScale(Scale); |
| if (const auto *MaybeCallArg = selectFirst<const Expr>( |
| "e", |
| match(callExpr(callee(functionDecl(hasAnyName( |
| InverseFunctions.first, InverseFunctions.second))), |
| hasArgument(0, expr().bind("e"))), |
| Node, *Result.Context))) { |
| return tooling::fixit::getText(*MaybeCallArg, *Result.Context).str(); |
| } |
| |
| return llvm::None; |
| } |
| |
| /// Returns the factory function name for a given `Scale`. |
| llvm::StringRef getFactoryForScale(DurationScale Scale) { |
| switch (Scale) { |
| case DurationScale::Hours: |
| return "absl::Hours"; |
| case DurationScale::Minutes: |
| return "absl::Minutes"; |
| case DurationScale::Seconds: |
| return "absl::Seconds"; |
| case DurationScale::Milliseconds: |
| return "absl::Milliseconds"; |
| case DurationScale::Microseconds: |
| return "absl::Microseconds"; |
| case DurationScale::Nanoseconds: |
| return "absl::Nanoseconds"; |
| } |
| llvm_unreachable("unknown scaling factor"); |
| } |
| |
| /// Returns `true` if `Node` is a value which evaluates to a literal `0`. |
| bool IsLiteralZero(const MatchFinder::MatchResult &Result, const Expr &Node) { |
| return selectFirst<const clang::Expr>( |
| "val", |
| match(expr(ignoringImpCasts(anyOf(integerLiteral(equals(0)), |
| floatLiteral(equals(0.0))))) |
| .bind("val"), |
| Node, *Result.Context)) != nullptr; |
| } |
| |
| llvm::Optional<std::string> |
| stripFloatCast(const ast_matchers::MatchFinder::MatchResult &Result, |
| const Expr &Node) { |
| if (const Expr *MaybeCastArg = selectFirst<const Expr>( |
| "cast_arg", |
| match(expr(anyOf(cxxStaticCastExpr( |
| hasDestinationType(realFloatingPointType()), |
| hasSourceExpression(expr().bind("cast_arg"))), |
| cStyleCastExpr( |
| hasDestinationType(realFloatingPointType()), |
| hasSourceExpression(expr().bind("cast_arg"))), |
| cxxFunctionalCastExpr( |
| hasDestinationType(realFloatingPointType()), |
| hasSourceExpression(expr().bind("cast_arg"))))), |
| Node, *Result.Context))) |
| return tooling::fixit::getText(*MaybeCastArg, *Result.Context).str(); |
| |
| return llvm::None; |
| } |
| |
| llvm::Optional<std::string> |
| stripFloatLiteralFraction(const MatchFinder::MatchResult &Result, |
| const Expr &Node) { |
| if (const auto *LitFloat = llvm::dyn_cast<FloatingLiteral>(&Node)) |
| // Attempt to simplify a `Duration` factory call with a literal argument. |
| if (llvm::Optional<llvm::APSInt> IntValue = truncateIfIntegral(*LitFloat)) |
| return IntValue->toString(/*radix=*/10); |
| |
| return llvm::None; |
| } |
| |
| std::string simplifyDurationFactoryArg(const MatchFinder::MatchResult &Result, |
| const Expr &Node) { |
| // Check for an explicit cast to `float` or `double`. |
| if (llvm::Optional<std::string> MaybeArg = stripFloatCast(Result, Node)) |
| return *MaybeArg; |
| |
| // Check for floats without fractional components. |
| if (llvm::Optional<std::string> MaybeArg = |
| stripFloatLiteralFraction(Result, Node)) |
| return *MaybeArg; |
| |
| // We couldn't simplify any further, so return the argument text. |
| return tooling::fixit::getText(Node, *Result.Context).str(); |
| } |
| |
| llvm::Optional<DurationScale> getScaleForInverse(llvm::StringRef Name) { |
| static const llvm::StringMap<DurationScale> ScaleMap( |
| {{"ToDoubleHours", DurationScale::Hours}, |
| {"ToInt64Hours", DurationScale::Hours}, |
| {"ToDoubleMinutes", DurationScale::Minutes}, |
| {"ToInt64Minutes", DurationScale::Minutes}, |
| {"ToDoubleSeconds", DurationScale::Seconds}, |
| {"ToInt64Seconds", DurationScale::Seconds}, |
| {"ToDoubleMilliseconds", DurationScale::Milliseconds}, |
| {"ToInt64Milliseconds", DurationScale::Milliseconds}, |
| {"ToDoubleMicroseconds", DurationScale::Microseconds}, |
| {"ToInt64Microseconds", DurationScale::Microseconds}, |
| {"ToDoubleNanoseconds", DurationScale::Nanoseconds}, |
| {"ToInt64Nanoseconds", DurationScale::Nanoseconds}}); |
| |
| auto ScaleIter = ScaleMap.find(std::string(Name)); |
| if (ScaleIter == ScaleMap.end()) |
| return llvm::None; |
| |
| return ScaleIter->second; |
| } |
| |
| llvm::Optional<std::string> rewriteExprFromNumberToDuration( |
| const ast_matchers::MatchFinder::MatchResult &Result, DurationScale Scale, |
| const Expr *Node) { |
| const Expr &RootNode = *Node->IgnoreParenImpCasts(); |
| |
| if (RootNode.getBeginLoc().isMacroID()) |
| return llvm::None; |
| |
| // First check to see if we can undo a complimentary function call. |
| if (llvm::Optional<std::string> MaybeRewrite = |
| rewriteInverseDurationCall(Result, Scale, RootNode)) |
| return *MaybeRewrite; |
| |
| if (IsLiteralZero(Result, RootNode)) |
| return std::string("absl::ZeroDuration()"); |
| |
| return (llvm::Twine(getFactoryForScale(Scale)) + "(" + |
| simplifyDurationFactoryArg(Result, RootNode) + ")") |
| .str(); |
| } |
| |
| } // namespace abseil |
| } // namespace tidy |
| } // namespace clang |