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Diffstat (limited to 'compilerplugins/clang/inlinesimplememberfunctions.cxx')
| -rw-r--r-- | compilerplugins/clang/inlinesimplememberfunctions.cxx | 282 |
1 files changed, 282 insertions, 0 deletions
diff --git a/compilerplugins/clang/inlinesimplememberfunctions.cxx b/compilerplugins/clang/inlinesimplememberfunctions.cxx new file mode 100644 index 000000000000..4bee14c25200 --- /dev/null +++ b/compilerplugins/clang/inlinesimplememberfunctions.cxx @@ -0,0 +1,282 @@ +/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */ +/* + * This file is part of the LibreOffice project. + * + * This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. + */ + +#include <string> + +#include "plugin.hxx" + +// Methods that purely return a local field should be declared in the header and be declared inline. +// So that the compiler can elide the function call and turn it into a simple fixed-offset-load instruction. + +namespace { + +class InlineSimpleMemberFunctions: + public RecursiveASTVisitor<InlineSimpleMemberFunctions>, public loplugin::RewritePlugin +{ +public: + explicit InlineSimpleMemberFunctions(InstantiationData const & data): RewritePlugin(data) {} + + virtual void run() override { TraverseDecl(compiler.getASTContext().getTranslationUnitDecl()); } + + bool VisitCXXMethodDecl(const CXXMethodDecl * decl); +private: + bool isInUnoIncludeFile(SourceLocation spellingLocation) const; + bool isInMainFile(SourceLocation spellingLocation) const; + bool rewrite(const CXXMethodDecl * functionDecl); +}; + +static bool oneAndOnlyOne(clang::Stmt::const_child_range range) { + if (range.empty()) { + return false; + } + if ((++range.first) != range.second) { + return false; + } + return true; +} + + +bool InlineSimpleMemberFunctions::VisitCXXMethodDecl(const CXXMethodDecl * functionDecl) { + if (ignoreLocation(functionDecl)) { + return true; + } + // no point in doing virtual methods, the compiler always has to generate a vtable entry and a method + if (functionDecl->isVirtual()) { + return true; + } + if (functionDecl->getTemplatedKind() != FunctionDecl::TK_NonTemplate) { + return true; + } + if (!functionDecl->isInstance()) { + return true; + } + if (!functionDecl->isOutOfLine()) { + return true; + } + if( !functionDecl->hasBody()) { + return true; + } + if( functionDecl->isInlineSpecified()) { + return true; + } + // ignore stuff that forms part of the stable URE interface + if (isInUnoIncludeFile(compiler.getSourceManager().getSpellingLoc( + functionDecl->getCanonicalDecl()->getNameInfo().getLoc()))) { + return true; + } + // ignore stuff like: + // template<class E> E * Sequence<E>::begin() { return getArray(); } + if( functionDecl->getParent()->getDescribedClassTemplate() != nullptr ) { + return true; + } + + /* + The chain here looks like + CompoundStmt + ReturnStmt + other stuff + CXXThisExpr + */ + + const CompoundStmt* compoundStmt = dyn_cast< CompoundStmt >( functionDecl->getBody() ); + if (compoundStmt == nullptr) { + return true; + } + if (compoundStmt->body_begin() == compoundStmt->body_end()) { + return true; + } + + + const Stmt* childStmt = *compoundStmt->child_begin(); + + if (dyn_cast<ReturnStmt>( childStmt ) == nullptr) { + return true; + } + if (!oneAndOnlyOne(childStmt->children())) { + return true; + } + + + /* Don't warn if we see a method definition like + X X::a() { + return *this; + } + which translates to: + CompoundStmt + ReturnStmt + ImplicitCastExpr + UnaryOperator + CXXThisExpr + or: + CompoundStmt + ReturnStmt + UnaryOperator + CXXThisExpr + */ + childStmt = *childStmt->child_begin(); + if (dyn_cast<ImplicitCastExpr>( childStmt ) != nullptr + && oneAndOnlyOne( childStmt->children() )) + { + const Stmt* childStmt2 = *childStmt->child_begin(); + if (dyn_cast<UnaryOperator>( childStmt2 ) != nullptr + && oneAndOnlyOne(childStmt2->children())) + { + childStmt2 = *childStmt2->child_begin(); + if (dyn_cast<CXXThisExpr>( childStmt2 ) != nullptr + && childStmt2->children().empty()) + { + return true; + } + } + } + if (dyn_cast<UnaryOperator>( childStmt ) != nullptr + && oneAndOnlyOne( childStmt->children() )) + { + const Stmt* childStmt2 = *childStmt->child_begin(); + if (dyn_cast<CXXThisExpr>( childStmt2 ) != nullptr + && childStmt2->children().empty()) + { + return true; + } + } + + /* look for a chain like: + CompoundStmt + ReturnStmt + ImplicitCastExpr + MemberExpr + CXXThisExpr + */ + if (dyn_cast<ImplicitCastExpr>( childStmt ) != nullptr + && oneAndOnlyOne( childStmt->children() )) + { + const Stmt* childStmt2 = *childStmt->child_begin(); + if (dyn_cast<MemberExpr>( childStmt2 ) != nullptr + && oneAndOnlyOne(childStmt2->children())) + { + childStmt2 = *childStmt2->child_begin(); + if (dyn_cast<CXXThisExpr>( childStmt2 ) != nullptr + && childStmt2->children().empty()) + { + if (!rewrite(functionDecl)) + { + report( + DiagnosticsEngine::Warning, + "inlinesimpleaccessmethods", + functionDecl->getSourceRange().getBegin()) + << functionDecl->getSourceRange(); + } + return true; + } + } + } + + return true; +} + +bool InlineSimpleMemberFunctions::isInUnoIncludeFile(SourceLocation spellingLocation) const { + StringRef name { + compiler.getSourceManager().getFilename(spellingLocation) }; + return isInMainFile(spellingLocation) + ? (name == SRCDIR "/cppu/source/cppu/compat.cxx" + || name == SRCDIR "/cppuhelper/source/compat.cxx" + || name == SRCDIR "/sal/osl/all/compat.cxx") + : (name.startswith(SRCDIR "/include/com/") + || name.startswith(SRCDIR "/include/cppu/") + || name.startswith(SRCDIR "/include/cppuhelper/") + || name.startswith(SRCDIR "/include/osl/") + || name.startswith(SRCDIR "/include/rtl/") + || name.startswith(SRCDIR "/include/sal/") + || name.startswith(SRCDIR "/include/salhelper/") + || name.startswith(SRCDIR "/include/systools/") + || name.startswith(SRCDIR "/include/typelib/") + || name.startswith(SRCDIR "/include/uno/") + || name == SRCDIR "/include/comphelper/implbase_var.hxx"); +} + +bool InlineSimpleMemberFunctions::isInMainFile(SourceLocation spellingLocation) const { +#if (__clang_major__ == 3 && __clang_minor__ >= 4) || __clang_major__ > 3 + return compiler.getSourceManager().isInMainFile(spellingLocation); +#else + return compiler.getSourceManager().isFromMainFile(spellingLocation); +#endif +} + +static std::string ReplaceString(std::string subject, const std::string& search, + const std::string& replace) { + size_t pos = 0; + while ((pos = subject.find(search, pos)) != std::string::npos) { + subject.replace(pos, search.length(), replace); + pos += replace.length(); + } + return subject; +} + +bool InlineSimpleMemberFunctions::rewrite(const CXXMethodDecl * functionDecl) { + if (rewriter == nullptr) { + return false; + } + // Only rewrite declarations in include files if a + // definition is also seen, to avoid compilation of a + // definition (in a main file only processed later) to fail + // with a "mismatch" error before the rewriter had a chance + // to act upon the definition. + if (!isInMainFile( + compiler.getSourceManager().getSpellingLoc( + functionDecl->getNameInfo().getLoc()))) { + return false; + } + + const char *p1, *p2; + + // get the function body contents + p1 = compiler.getSourceManager().getCharacterData( functionDecl->getBody()->getLocStart() ); + p2 = compiler.getSourceManager().getCharacterData( functionDecl->getBody()->getLocEnd() ); + std::string s1( p1, p2 - p1 + 1); + // strip linefeeds and any double-spaces, so we have a max of one space between tokens + s1 = ReplaceString(s1, "\r", ""); + s1 = ReplaceString(s1, "\n", ""); + s1 = ReplaceString(s1, "\t", " "); + s1 = ReplaceString(s1, " ", " "); + s1 = ReplaceString(s1, " ", " "); + s1 = ReplaceString(s1, " ", " "); + s1 = " " + s1; + + // scan from the end of the functions body through the whitespace, so we can do a nice clean remove +// commented out because for some reason it will sometimes chomp an extra token +// SourceLocation endOfRemoveLoc = functionDecl->getBody()->getLocEnd(); +// for (;;) { +// endOfRemoveLoc = endOfRemoveLoc.getLocWithOffset(1); +// p1 = compiler.getSourceManager().getCharacterData( endOfRemoveLoc ); +// if (*p1 != ' ' && *p1 != '\r' && *p1 != '\n' && *p1 != '\t') +// break; +// } + + // remove the function's out of line body and declaration + RewriteOptions opts; + opts.RemoveLineIfEmpty = true; + if (!removeText(SourceRange(functionDecl->getLocStart(), functionDecl->getBody()->getLocEnd()), opts)) { + return false; + } + + // scan forward until we find the semicolon + const FunctionDecl * canonicalDecl = functionDecl->getCanonicalDecl(); + p1 = compiler.getSourceManager().getCharacterData( canonicalDecl->getLocEnd() ); + p2 = ++p1; + while (*p2 != 0 && *p2 != ';') p2++; + + // insert the function body into the inline function definition (i.e. the one inside the class definition) + return replaceText(canonicalDecl->getLocEnd().getLocWithOffset(p2 - p1 + 1), 1, s1); +} + +loplugin::Plugin::Registration< InlineSimpleMemberFunctions > X("inlinesimplememberfunctions"); + +} + +/* vim:set shiftwidth=4 softtabstop=4 expandtab: */ |