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1//===----------------------------------------------------------------------===//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-exception6//7//===----------------------------------------------------------------------===//8 9#ifndef LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_ALTERA_UNROLLLOOPSCHECK_H10#define LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_ALTERA_UNROLLLOOPSCHECK_H11 12#include "../ClangTidyCheck.h"13 14namespace clang::tidy::altera {15 16/// Finds inner loops that have not been unrolled, as well as fully unrolled17/// loops with unknown loop bounds or a large number of iterations.18///19/// Unrolling inner loops could improve the performance of OpenCL kernels.20/// However, if they have unknown loop bounds or a large number of iterations,21/// they cannot be fully unrolled, and should be partially unrolled.22///23/// For the user-facing documentation see:24/// https://clang.llvm.org/extra/clang-tidy/checks/altera/unroll-loops.html25class UnrollLoopsCheck : public ClangTidyCheck {26public:27 UnrollLoopsCheck(StringRef Name, ClangTidyContext *Context);28 void registerMatchers(ast_matchers::MatchFinder *Finder) override;29 void check(const ast_matchers::MatchFinder::MatchResult &Result) override;30 31private:32 /// Recommend partial unrolling if number of loop iterations is greater than33 /// MaxLoopIterations.34 const unsigned MaxLoopIterations;35 /// The kind of unrolling, if any, applied to a given loop.36 enum UnrollType {37 // This loop has no #pragma unroll directive associated with it.38 NotUnrolled,39 // This loop has a #pragma unroll directive associated with it.40 FullyUnrolled,41 // This loop has a #pragma unroll <num> directive associated with it.42 PartiallyUnrolled43 };44 /// Attempts to extract an integer value from either side of the45 /// BinaryOperator. Returns true and saves the result to &value if successful,46 /// returns false otherwise.47 bool extractValue(int &Value, const BinaryOperator *Op,48 const ASTContext *Context);49 /// Returns true if the given loop statement has a large number of iterations,50 /// as determined by the integer value in the loop's condition expression,51 /// if one exists.52 bool hasLargeNumIterations(const Stmt *Statement,53 const IntegerLiteral *CXXLoopBound,54 const ASTContext *Context);55 /// Checks one hand side of the binary operator to ascertain if the upper56 /// bound on the number of loops is greater than max_loop_iterations or not.57 /// If the expression is not evaluatable or not an integer, returns false.58 bool exprHasLargeNumIterations(const Expr *Expression,59 const ASTContext *Context) const;60 /// Returns the type of unrolling, if any, associated with the given61 /// statement.62 enum UnrollType unrollType(const Stmt *Statement, ASTContext *Context);63 /// Returns the condition expression within a given for statement. If there is64 /// none, or if the Statement is not a loop, then returns a NULL pointer.65 const Expr *getCondExpr(const Stmt *Statement);66 /// Returns True if the loop statement has known bounds.67 bool hasKnownBounds(const Stmt *Statement, const IntegerLiteral *CXXLoopBound,68 const ASTContext *Context);69 void storeOptions(ClangTidyOptions::OptionMap &Opts) override;70};71 72} // namespace clang::tidy::altera73 74#endif // LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_ALTERA_UNROLLLOOPSCHECK_H75