compilerplugins/clang/store/removevirtuals.cxx

   1 /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
   2 /*
   3  * This file is part of the LibreOffice project.
   4  *
   5  * This Source Code Form is subject to the terms of the Mozilla Public
   6  * License, v. 2.0. If a copy of the MPL was not distributed with this
   7  * file, You can obtain one at http://mozilla.org/MPL/2.0/.
   8  */
   9
  10 #include <cassert>
  11 #include <string>
  12 #include <iostream>
  13 #include "plugin.hxx"
  14 #include "compat.hxx"
  15 #include <sys/mman.h>
  16 #include <sys/types.h>
  17 #include <fcntl.h>
  18 #include <unistd.h>
  19 #include <sys/stat.h>
  20 #include <assert.h>
  21 #include <cstring>
  22
  23 /**
  24   This is intended to be run as the second stage of the "unnecessaryvirtuals" clang plugin.
  25 */
  26
  27 namespace {
  28
  29 class RemoveVirtuals:
  30     public RecursiveASTVisitor<RemoveVirtuals>, public loplugin::RewritePlugin
  31 {
  32 public:
  33     explicit RemoveVirtuals(InstantiationData const & data);
  34     ~RemoveVirtuals();
  35
  36     virtual void run() override { TraverseDecl(compiler.getASTContext().getTranslationUnitDecl()); }
  37
  38     bool VisitCXXMethodDecl( const CXXMethodDecl* var );
  39 private:
  40     // I use a brute-force approach - mmap the results file and do a linear search on it
  41     // It works surprisingly well, because the file is small enough to fit into L2 cache on modern CPU's
  42     size_t mmapFilesize;
  43     int mmapFD;
  44     char* mmappedData;
  45 };
  46
  47 static size_t getFilesize(const char* filename)
  48 {
  49     struct stat st;
  50     stat(filename, &st);
  51     return st.st_size;
  52 }
  53
  54 RemoveVirtuals::RemoveVirtuals(InstantiationData const & data): RewritePlugin(data)
  55 {
  56     static const char sInputFile[] = "/home/noel/libo4/result.txt";
  57     mmapFilesize = getFilesize(sInputFile);
  58     //Open file
  59     mmapFD = open(sInputFile, O_RDONLY, 0);
  60     assert(mmapFD != -1);
  61     //Execute mmap
  62     mmappedData = static_cast<char*>(mmap(NULL, mmapFilesize, PROT_READ, MAP_PRIVATE | MAP_POPULATE, mmapFD, 0));
  63     assert(mmappedData != NULL);
  64 }
  65
  66 RemoveVirtuals::~RemoveVirtuals()
  67 {
  68     //Cleanup
  69     int rc = munmap(mmappedData, mmapFilesize);
  70     assert(rc == 0);
  71     close(mmapFD);
  72 }
  73
  74 static std::string niceName(const CXXMethodDecl* functionDecl)
  75 {
  76     std::string s =
  77            functionDecl->getParent()->getQualifiedNameAsString() + "::"
  78            + compat::getReturnType(*functionDecl).getAsString() + "-"
  79            + functionDecl->getNameAsString() + "(";
  80     for (const ParmVarDecl *pParmVarDecl : functionDecl->params()) {
  81         s += pParmVarDecl->getType().getAsString();
  82         s += ",";
  83     }
  84     s += ")";
  85     if (functionDecl->isConst()) {
  86         s += "const";
  87     }
  88     return s;
  89 }
  90
  91 bool RemoveVirtuals::VisitCXXMethodDecl( const CXXMethodDecl* functionDecl )
  92 {
  93     if (rewriter == nullptr) {
  94         return true;
  95     }
  96     if (ignoreLocation(functionDecl)) {
  97         return true;
  98     }
  99     // ignore stuff that forms part of the stable URE interface
 100     if (isInUnoIncludeFile(compiler.getSourceManager().getSpellingLoc(
 101                               functionDecl->getCanonicalDecl()->getNameInfo().getLoc()))) {
 102         return true;
 103     }
 104
 105     // don't mess with templates
 106     if (functionDecl->getParent()->getDescribedClassTemplate() != nullptr) {
 107         return true;
 108     }
 109     if (functionDecl->getTemplatedKind() != FunctionDecl::TK_NonTemplate) {
 110         return true;
 111     }
 112
 113     if (!functionDecl->isVirtualAsWritten()) {
 114         return true;
 115     }
 116     std::string aNiceName = "\n" + niceName(functionDecl) + "\n";
 117     const char *aNiceNameStr = aNiceName.c_str();
 118     char* found = std::search(mmappedData, mmappedData + mmapFilesize, aNiceNameStr, aNiceNameStr + strlen(aNiceNameStr));
 119     if(!(found < mmappedData + mmapFilesize)) {
 120         return true;
 121     }
 122     if (functionDecl->isPure()) {
 123         removeText(functionDecl->getSourceRange());
 124     } else {
 125         std::string aOrigText = rewriter->getRewrittenText(functionDecl->getSourceRange());
 126         size_t iVirtualTokenIndex = aOrigText.find_first_of("virtual ");
 127         if (iVirtualTokenIndex == std::string::npos) {
 128             return true;
 129         }
 130         replaceText(functionDecl->getSourceRange(), aOrigText.replace(iVirtualTokenIndex, strlen("virtual "), ""));
 131     }
 132     return true;
 133 }
 134
 135
 136
 137 loplugin::Plugin::Registration< RemoveVirtuals > X("removevirtuals", false);
 138
 139 }
 140
 141 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */