1//===-- MPIChecker.h - Verify MPI API usage- --------------------*- C++ -*-===//
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/// \file
10/// This file defines the main class of MPI-Checker which serves as an entry
11/// point. It is created once for each translation unit analysed.
12/// The checker defines path-sensitive checks, to verify correct usage of the
13/// MPI API.
14///
15//===----------------------------------------------------------------------===//
16
17#ifndef LLVM_CLANG_LIB_STATICANALYZER_CHECKERS_MPICHECKER_MPICHECKER_H
18#define LLVM_CLANG_LIB_STATICANALYZER_CHECKERS_MPICHECKER_MPICHECKER_H
19
20#include "MPIBugReporter.h"
21#include "MPITypes.h"
22#include "clang/StaticAnalyzer/Checkers/MPIFunctionClassifier.h"
23#include "clang/StaticAnalyzer/Core/PathSensitive/CallEvent.h"
24#include "clang/StaticAnalyzer/Core/PathSensitive/CheckerContext.h"
25
26namespace clang {
27namespace ento {
28namespace mpi {
29
30class MPIChecker : public Checker<check::PreCall, check::DeadSymbols> {
31public:
32  MPIChecker() : BReporter(*this) {}
33
34  // path-sensitive callbacks
35  void checkPreCall(const CallEvent &CE, CheckerContext &Ctx) const {
36    dynamicInit(Ctx);
37    checkUnmatchedWaits(CE, Ctx);
38    checkDoubleNonblocking(CE, Ctx);
39  }
40
41  void checkDeadSymbols(SymbolReaper &SymReaper, CheckerContext &Ctx) const {
42    dynamicInit(Ctx);
43    checkMissingWaits(SymReaper, Ctx);
44  }
45
46  void dynamicInit(CheckerContext &Ctx) const {
47    if (FuncClassifier)
48      return;
49    const_cast<std::unique_ptr<MPIFunctionClassifier> &>(FuncClassifier)
50        .reset(new MPIFunctionClassifier{Ctx.getASTContext()});
51  }
52
53  /// Checks if a request is used by nonblocking calls multiple times
54  /// in sequence without intermediate wait. The check contains a guard,
55  /// in order to only inspect nonblocking functions.
56  ///
57  /// \param PreCallEvent MPI call to verify
58  void checkDoubleNonblocking(const clang::ento::CallEvent &PreCallEvent,
59                              clang::ento::CheckerContext &Ctx) const;
60
61  /// Checks if the request used by the wait function was not used at all
62  /// before. The check contains a guard, in order to only inspect wait
63  /// functions.
64  ///
65  /// \param PreCallEvent MPI call to verify
66  void checkUnmatchedWaits(const clang::ento::CallEvent &PreCallEvent,
67                           clang::ento::CheckerContext &Ctx) const;
68
69  /// Check if a nonblocking call is not matched by a wait.
70  /// If a memory region is not alive and the last function using the
71  /// request was a nonblocking call, this is rated as a missing wait.
72  void checkMissingWaits(clang::ento::SymbolReaper &SymReaper,
73                         clang::ento::CheckerContext &Ctx) const;
74
75private:
76  /// Collects all memory regions of a request(array) used by a wait
77  /// function. If the wait function uses a single request, this is a single
78  /// region. For wait functions using multiple requests, multiple regions
79  /// representing elements in the array are collected.
80  ///
81  /// \param ReqRegions vector the regions get pushed into
82  /// \param MR top most region to iterate
83  /// \param CE MPI wait call using the request(s)
84  void allRegionsUsedByWait(
85      llvm::SmallVector<const clang::ento::MemRegion *, 2> &ReqRegions,
86      const clang::ento::MemRegion *const MR, const clang::ento::CallEvent &CE,
87      clang::ento::CheckerContext &Ctx) const;
88
89  /// Returns the memory region used by a wait function.
90  /// Distinguishes between MPI_Wait and MPI_Waitall.
91  ///
92  /// \param CE MPI wait call
93  const clang::ento::MemRegion *
94  topRegionUsedByWait(const clang::ento::CallEvent &CE) const;
95
96  const std::unique_ptr<MPIFunctionClassifier> FuncClassifier;
97  MPIBugReporter BReporter;
98};
99
100} // end of namespace: mpi
101} // end of namespace: ento
102} // end of namespace: clang
103
104#endif
105