summaryrefslogtreecommitdiffstats
path: root/compilerplugins/clang/moveit.cxx
diff options
context:
space:
mode:
Diffstat (limited to 'compilerplugins/clang/moveit.cxx')
-rw-r--r--compilerplugins/clang/moveit.cxx250
1 files changed, 250 insertions, 0 deletions
diff --git a/compilerplugins/clang/moveit.cxx b/compilerplugins/clang/moveit.cxx
new file mode 100644
index 000000000..353359e28
--- /dev/null
+++ b/compilerplugins/clang/moveit.cxx
@@ -0,0 +1,250 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * Based on LLVM/Clang.
+ *
+ * This file is distributed under the University of Illinois Open Source
+ * License. See LICENSE.TXT for details.
+ *
+ */
+
+#include <cassert>
+#include <string>
+#include <iostream>
+#include <fstream>
+#include "config_clang.h"
+#include "plugin.hxx"
+#include "check.hxx"
+
+/*
+Look for local variables that can be std::move'd into parameters.
+
+TODO
+(*) Ideally we would use a proper data-flow analysis, to detect that the var is dead after this point,
+ like the one in clang at include/clang/Analysis/CFG.h
+(*) we could expand the set of approved/interesting types
+*/
+
+namespace
+{
+class MoveIt : public loplugin::FilteringPlugin<MoveIt>
+{
+public:
+ explicit MoveIt(loplugin::InstantiationData const& data)
+ : FilteringPlugin(data)
+ {
+ }
+
+ virtual bool preRun() override
+ {
+ std::string fn(handler.getMainFileName());
+ loplugin::normalizeDotDotInFilePath(fn);
+ // false +
+ if (loplugin::hasPathnamePrefix(fn, SRCDIR "/basic/source/classes/sbunoobj.cxx"))
+ return false;
+ if (loplugin::hasPathnamePrefix(fn, SRCDIR "/svx/source/svdraw/textchainflow.cxx"))
+ return false;
+ if (loplugin::hasPathnamePrefix(fn, SRCDIR "/svx/source/unodraw/unoshtxt.cxx"))
+ return false;
+ if (loplugin::hasPathnamePrefix(fn,
+ SRCDIR "/connectivity/source/drivers/dbase/dindexnode.cxx"))
+ return false;
+ if (loplugin::hasPathnamePrefix(fn, SRCDIR "/basctl/source/basicide/moduldlg.cxx"))
+ return false;
+ if (loplugin::hasPathnamePrefix(fn, SRCDIR "/sw/source/core/SwNumberTree/SwNumberTree.cxx"))
+ return false;
+ if (loplugin::hasPathnamePrefix(fn, SRCDIR "/sc/source/core/tool/scmatrix.cxx"))
+ return false;
+ if (loplugin::hasPathnamePrefix(fn, SRCDIR "/sw/source/core/bastyp/calc.cxx"))
+ return false;
+ if (loplugin::hasPathnamePrefix(fn, SRCDIR "/sw/source/core/edit/edattr.cxx"))
+ return false;
+ if (loplugin::hasPathnamePrefix(fn, SRCDIR "/sw/source/core/fields/expfld.cxx"))
+ return false;
+ if (loplugin::hasPathnamePrefix(fn, SRCDIR "/sw/source/uibase/docvw/edtwin.cxx"))
+ return false;
+ if (loplugin::hasPathnamePrefix(fn, SRCDIR "/sw/source/uibase/uiview/viewling.cxx"))
+ return false;
+ if (loplugin::hasPathnamePrefix(
+ fn, SRCDIR "/writerfilter/source/dmapper/DomainMapperTableHandler.cxx"))
+ return false;
+ return true;
+ }
+
+ virtual void run() override
+ {
+ if (preRun())
+ TraverseDecl(compiler.getASTContext().getTranslationUnitDecl());
+ }
+
+ bool VisitCXXMemberCallExpr(const CXXMemberCallExpr*);
+ bool VisitCXXConstructExpr(const CXXConstructExpr*);
+
+private:
+ bool isInterestingType(QualType);
+};
+
+bool MoveIt::VisitCXXMemberCallExpr(const CXXMemberCallExpr* topExpr)
+{
+ if (ignoreLocation(topExpr))
+ return true;
+ const CXXMethodDecl* methodDecl = topExpr->getMethodDecl();
+ if (!methodDecl)
+ return true;
+
+ unsigned len = std::min(topExpr->getNumArgs(), methodDecl->getNumParams());
+ for (unsigned i = 0; i < len; ++i)
+ {
+ // check if the parameter is a moveable type
+ const ParmVarDecl* parmVarDecl = methodDecl->getParamDecl(i);
+ if (!parmVarDecl->getType()->isRecordType())
+ continue;
+ const CXXRecordDecl* recordDecl
+ = dyn_cast<CXXRecordDecl>(parmVarDecl->getType()->getAsRecordDecl());
+ if (!recordDecl || !recordDecl->hasMoveConstructor() || recordDecl->isTriviallyCopyable())
+ continue;
+ if (!isInterestingType(parmVarDecl->getType()))
+ continue;
+
+ // check if (a) we're making a copy to pass to the param and (b) we're making a copy of a local var
+ const Expr* argExpr = topExpr->getArg(i);
+ if (!argExpr)
+ continue;
+ const CXXConstructExpr* argSubExpr = dyn_cast<CXXConstructExpr>(argExpr->IgnoreImplicit());
+ if (!argSubExpr || argSubExpr->getNumArgs() == 0)
+ continue;
+ const DeclRefExpr* dre = dyn_cast<DeclRefExpr>(argSubExpr->getArg(0)->IgnoreImplicit());
+ if (!dre)
+ continue;
+ const VarDecl* localVarDecl = dyn_cast<VarDecl>(dre->getDecl());
+ if (!localVarDecl || localVarDecl->getType()->isReferenceType()
+ || localVarDecl->getType()->isPointerType() || !localVarDecl->hasLocalStorage())
+ continue;
+ // because sometimes the parameter type is some obscured STL thing
+ if (!isInterestingType(localVarDecl->getType()))
+ continue;
+
+ report(DiagnosticsEngine::Warning, "can std::move this var into this param",
+ argExpr->getBeginLoc());
+ report(DiagnosticsEngine::Note, "passing to this param", parmVarDecl->getBeginLoc());
+ report(DiagnosticsEngine::Note, "local var declared here", localVarDecl->getBeginLoc());
+ report(DiagnosticsEngine::Note, "type declared here", recordDecl->getBeginLoc());
+ // parmVarDecl->getType()->dump();
+ }
+
+ // StringRef aFileName = getFilenameOfLocation(
+ // compiler.getSourceManager().getSpellingLoc(parmVarDecl->getBeginLoc()));
+ // if (loplugin::hasPathnamePrefix(aFileName,
+ // SRCDIR "/svx/source/sidebar/line/LineWidthValueSet.cxx"))
+ // return true;
+
+ return true;
+}
+
+bool MoveIt::VisitCXXConstructExpr(const CXXConstructExpr* topExpr)
+{
+ if (ignoreLocation(topExpr))
+ return true;
+ if (isa<CXXTemporaryObjectExpr>(topExpr))
+ return true;
+ const CXXConstructorDecl* methodDecl = topExpr->getConstructor();
+ if (!methodDecl)
+ return true;
+
+ unsigned len = std::min(topExpr->getNumArgs(), methodDecl->getNumParams());
+ for (unsigned i = 0; i < len; ++i)
+ {
+ // check if the parameter is a moveable type
+ const ParmVarDecl* parmVarDecl = methodDecl->getParamDecl(i);
+ if (!parmVarDecl->getType()->isRecordType())
+ continue;
+ const CXXRecordDecl* recordDecl
+ = dyn_cast<CXXRecordDecl>(parmVarDecl->getType()->getAsRecordDecl());
+ if (!recordDecl || !recordDecl->hasMoveConstructor() || recordDecl->isTriviallyCopyable())
+ continue;
+ if (!isInterestingType(parmVarDecl->getType()))
+ continue;
+
+ // check if (a) we're making a copy to pass to the param and (b) we're making a copy of a local var
+ const Expr* argExpr = topExpr->getArg(i);
+ if (!argExpr)
+ continue;
+ const CXXConstructExpr* argSubExpr = dyn_cast<CXXConstructExpr>(argExpr->IgnoreImplicit());
+ if (!argSubExpr || argSubExpr->getNumArgs() == 0)
+ continue;
+ const DeclRefExpr* dre = dyn_cast<DeclRefExpr>(argSubExpr->getArg(0)->IgnoreImplicit());
+ if (!dre)
+ continue;
+ const VarDecl* localVarDecl = dyn_cast<VarDecl>(dre->getDecl());
+ if (!localVarDecl || localVarDecl->getType()->isReferenceType()
+ || localVarDecl->getType()->isPointerType() || !localVarDecl->hasLocalStorage())
+ continue;
+ // because sometimes the parameter type is some obscured STL thing
+ if (!isInterestingType(localVarDecl->getType()))
+ continue;
+
+ report(DiagnosticsEngine::Warning, "can std::move this var into this param",
+ argExpr->getBeginLoc());
+ report(DiagnosticsEngine::Note, "passing to this param", parmVarDecl->getBeginLoc());
+ report(DiagnosticsEngine::Note, "local var declared here", localVarDecl->getBeginLoc());
+ report(DiagnosticsEngine::Note, "type declared here", recordDecl->getBeginLoc());
+ // parmVarDecl->getType()->dump();
+ }
+
+ // StringRef aFileName = getFilenameOfLocation(
+ // compiler.getSourceManager().getSpellingLoc(parmVarDecl->getBeginLoc()));
+ // if (loplugin::hasPathnamePrefix(aFileName,
+ // SRCDIR "/svx/source/sidebar/line/LineWidthValueSet.cxx"))
+ // return true;
+
+ return true;
+}
+
+/// Exclude boring types, so that we don't generate too many low-value conversions.
+/// e.g. for now I ignore ref-counted types like Sequence and OUString and css::uno::Reference,
+/// because that generates too many changes
+bool MoveIt::isInterestingType(QualType qt)
+{
+ if (qt->isEnumeralType())
+ return false;
+ if (!qt->isRecordType())
+ return false;
+
+ auto tc = loplugin::TypeCheck(qt);
+
+ // clang-format off
+ return !tc.ClassOrStruct("iterator")
+ && !tc.ClassOrStruct("const_iterator")
+ && !tc.Typedef("iterator")
+ && !tc.Typedef("const_iterator")
+ && !tc.Class("_Safe_iterator")
+ && !tc.Typedef("string")
+ && !tc.ClassOrStruct("shared_ptr").StdNamespace()
+ && !tc.ClassOrStruct("shared_ptr").Namespace("boost")
+ && !tc.Class("B2DHomMatrix").Namespace("basegfx").GlobalNamespace()
+ && !tc.Class("Pipe").Namespace("osl")
+ && !tc.Class("Any").Namespace("uno")
+ && !tc.Class("TypeDescription").Namespace("uno")
+ && !tc.Class("UnoInterfaceReference").Namespace("uno")
+ && !tc.Class("ByteSequence").Namespace("rtl").GlobalNamespace()
+ && !tc.Class("OUString").Namespace("rtl").GlobalNamespace()
+ && !tc.Class("OString").Namespace("rtl").GlobalNamespace()
+ && !tc.Class("BinaryAny")
+ && !tc.Class("Reference")
+ && !tc.Class("SvRef").Namespace("tools").GlobalNamespace()
+ && !tc.ClassOrStruct("sk_sp") // skia shared pointer
+ && !tc.ClassOrStruct("VclPtr")
+ && !tc.Typedef("IterString") // SalInstanceTreeView::IterString
+ && !tc.Typedef("svtree_render_args")
+ && !tc.Typedef("render_args") // weld::ComboBox::render_args
+ ;
+ // clang-format on
+}
+
+/// off by default because each warning needs to be hand checked to ensure it is not a false+
+loplugin::Plugin::Registration<MoveIt> moveit("moveit", false);
+
+} // namespace
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-11 02:53:49 +0000