compilerplugins/clang/moveparam.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  * Based on LLVM/Clang.
   6  *
   7  * This file is distributed under the University of Illinois Open Source
   8  * License. See LICENSE.TXT for details.
   9  *
  10  */
  11
  12 #include <cassert>
  13 #include <string>
  14 #include <iostream>
  15 #include <fstream>
  16 #include <set>
  17 #include <unordered_set>
  18 #include "config_clang.h"
  19 #include "plugin.hxx"
  20 #include "check.hxx"
  21
  22 /*
  23 Look for places where we can pass by move && param and so avoid
  24 unnecessary copies.
  25 Empirically, when we are passing a container type to a function, 80% of the time,
  26 we are passing a local temporary that can be moved instead of being copied.
  27
  28 TODO this could be a lot smarter, with ignoring false+ e.g. when copying a param
  29 in a loop
  30 */
  31
  32 namespace
  33 {
  34 class MoveParam : public loplugin::FilteringPlugin<MoveParam>
  35 {
  36 public:
  37     explicit MoveParam(loplugin::InstantiationData const& data)
  38         : FilteringPlugin(data)
  39     {
  40     }
  41
  42     virtual bool preRun() override
  43     {
  44         std::string fn(handler.getMainFileName());
  45         loplugin::normalizeDotDotInFilePath(fn);
  46         if (loplugin::hasPathnamePrefix(fn, SRCDIR "/filter/source/msfilter/escherex.cxx"))
  47             return false;
  48         if (loplugin::hasPathnamePrefix(fn, SRCDIR "/sc/source/ui/docshell/docfunc.cxx"))
  49             return false;
  50         if (loplugin::hasPathnamePrefix(fn, SRCDIR "/sc/source/ui/view/viewfunc.cxx"))
  51             return false;
  52         if (loplugin::hasPathnamePrefix(fn, SRCDIR "/basegfx/source/polygon/b2dpolygontools.cxx"))
  53             return false;
  54         if (loplugin::hasPathnamePrefix(fn, SRCDIR "/basegfx/source/polygon/b3dpolygontools.cxx"))
  55             return false;
  56         if (loplugin::hasPathnamePrefix(fn, SRCDIR "/connectivity/source/commontools/dbtools.cxx"))
  57             return false;
  58         return true;
  59     }
  60
  61     virtual void run() override
  62     {
  63         if (preRun())
  64             TraverseDecl(compiler.getASTContext().getTranslationUnitDecl());
  65     }
  66
  67     bool VisitCXXOperatorCallExpr(const CXXOperatorCallExpr*);
  68     bool VisitCXXConstructExpr(const CXXConstructExpr*);
  69
  70     bool isContainerType(QualType qt);
  71 };
  72
  73 bool MoveParam::VisitCXXOperatorCallExpr(const CXXOperatorCallExpr* callExpr)
  74 {
  75     if (ignoreLocation(callExpr))
  76         return true;
  77     if (!callExpr->isAssignmentOp())
  78         return true;
  79     auto qt = callExpr->getType();
  80     if (!isContainerType(qt))
  81         return true;
  82     auto declRef = dyn_cast<DeclRefExpr>(callExpr->getArg(1)->IgnoreParenImpCasts());
  83     if (!declRef)
  84         return true;
  85
  86     auto parmVarDecl = dyn_cast_or_null<ParmVarDecl>(declRef->getDecl());
  87     if (!parmVarDecl)
  88         return true;
  89
  90     if (!loplugin::TypeCheck(parmVarDecl->getType()).LvalueReference().Const())
  91         return true;
  92
  93     StringRef aFileName = getFilenameOfLocation(
  94         compiler.getSourceManager().getSpellingLoc(parmVarDecl->getBeginLoc()));
  95     if (loplugin::hasPathnamePrefix(aFileName,
  96                                     SRCDIR "/svx/source/sidebar/line/LineWidthValueSet.cxx"))
  97         return true;
  98
  99     report(DiagnosticsEngine::Warning, "rather use move && param1", callExpr->getBeginLoc());
 100
 101     return true;
 102 }
 103
 104 bool MoveParam::VisitCXXConstructExpr(const CXXConstructExpr* constructExpr)
 105 {
 106     if (ignoreLocation(constructExpr->getBeginLoc()))
 107         return true;
 108     if (isInUnoIncludeFile(constructExpr->getBeginLoc()))
 109         return true;
 110
 111     auto qt = constructExpr->getType();
 112     if (!isContainerType(qt))
 113         return true;
 114
 115     if (constructExpr->getNumArgs() != 1)
 116         return true;
 117
 118     auto declRef = dyn_cast<DeclRefExpr>(constructExpr->getArg(0)->IgnoreParenImpCasts());
 119     if (!declRef)
 120         return true;
 121
 122     auto parmVarDecl = dyn_cast_or_null<ParmVarDecl>(declRef->getDecl());
 123     if (!parmVarDecl)
 124         return true;
 125
 126     if (!loplugin::TypeCheck(parmVarDecl->getType()).LvalueReference().Const())
 127         return true;
 128
 129     StringRef aFileName = getFilenameOfLocation(
 130         compiler.getSourceManager().getSpellingLoc(parmVarDecl->getBeginLoc()));
 131     if (loplugin::hasPathnamePrefix(aFileName, SRCDIR
 132                                     "/include/drawinglayer/primitive2d/Primitive2DContainer.hxx"))
 133         return true;
 134     if (loplugin::hasPathnamePrefix(aFileName,
 135                                     SRCDIR "/include/drawinglayer/primitive3d/baseprimitive3d.hxx"))
 136         return true;
 137     if (loplugin::hasPathnamePrefix(aFileName, SRCDIR "/svx/source/svdraw/svdmrkv.cxx"))
 138         return true;
 139     if (loplugin::hasPathnamePrefix(aFileName, SRCDIR "/include/editeng/swafopt.hxx"))
 140         return true;
 141     if (loplugin::hasPathnamePrefix(
 142             aFileName, SRCDIR "/drawinglayer/source/primitive2d/textdecoratedprimitive2d.cxx"))
 143         return true;
 144     if (loplugin::hasPathnamePrefix(aFileName,
 145                                     SRCDIR "/chart2/source/tools/InternalDataProvider.cxx"))
 146         return true;
 147     if (loplugin::hasPathnamePrefix(aFileName, SRCDIR "/sc/source/core/data/attrib.cxx"))
 148         return true;
 149     if (loplugin::hasPathnamePrefix(aFileName, SRCDIR "/sw/source/core/doc/docfmt.cxx"))
 150         return true;
 151     if (loplugin::hasPathnamePrefix(aFileName, SRCDIR "/configmgr/source/modifications.cxx"))
 152         return true;
 153     if (loplugin::hasPathnamePrefix(aFileName, SRCDIR "/svx/source/dialog/srchdlg.cxx"))
 154         return true;
 155     if (loplugin::hasPathnamePrefix(aFileName,
 156                                     SRCDIR "/stoc/source/servicemanager/servicemanager.cxx"))
 157         return true;
 158
 159     report(DiagnosticsEngine::Warning, "rather use move && param3", constructExpr->getBeginLoc());
 160
 161     return true;
 162 }
 163
 164 bool MoveParam::isContainerType(QualType qt)
 165 {
 166     auto tc = loplugin::TypeCheck(qt);
 167     return tc.Class("Primitive2DContainer")
 168                .Namespace("primitive2d")
 169                .Namespace("drawinglayer")
 170                .GlobalNamespace()
 171            || tc.ClassOrStruct("sorted_vector").Namespace("o3tl").GlobalNamespace()
 172            || tc.ClassOrStruct("array").StdNamespace() || tc.ClassOrStruct("vector").StdNamespace()
 173            || tc.ClassOrStruct("deque").StdNamespace()
 174            || tc.ClassOrStruct("forward_list").StdNamespace()
 175            || tc.ClassOrStruct("list").StdNamespace() || tc.ClassOrStruct("set").StdNamespace()
 176            || tc.ClassOrStruct("map").StdNamespace() || tc.ClassOrStruct("multiset").StdNamespace()
 177            || tc.ClassOrStruct("multimap").StdNamespace()
 178            || tc.ClassOrStruct("unordered_set").StdNamespace()
 179            || tc.ClassOrStruct("unordered_map").StdNamespace()
 180            || tc.ClassOrStruct("unordered_multiset").StdNamespace()
 181            || tc.ClassOrStruct("unordered_multimap").StdNamespace()
 182            || tc.ClassOrStruct("stack").StdNamespace() || tc.ClassOrStruct("queue").StdNamespace()
 183            || tc.ClassOrStruct("priority_queue").StdNamespace();
 184 }
 185
 186 /** off by default because it needs some hand-holding */
 187 loplugin::Plugin::Registration<MoveParam> moveparam("moveparam", false);
 188
 189 } // namespace
 190
 191 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */