Add loplugin:redundantinline

...after it had recently been run with 6cb9e6dad798ec59f055aebe84a9c4a21e4be40d
"Remove redundant 'inline' keyword"

Change-Id: I7f3ee2ff1c32988dcff7245c64b50fe20b0a5e79
Reviewed-on: https://gerrit.libreoffice.org/35681
Reviewed-by: Stephan Bergmann <sbergman@redhat.com>
Tested-by: Stephan Bergmann <sbergman@redhat.com>

3 files changed, 220 insertions, 0 deletions

diff --git a/compilerplugins/clang/redundantinline.cxx b/compilerplugins/clang/redundantinline.cxx
new file mode 100644
index 000000000000..88c870d75465
--- /dev/null
+++ b/compilerplugins/clang/redundantinline.cxx
@@ -0,0 +1,127 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4; fill-column: 100 -*- */
+/*
+ * 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 <cassert>
+
+#include "plugin.hxx"
+
+namespace {
+
+class Visitor:
+    public RecursiveASTVisitor<Visitor>, public loplugin::RewritePlugin
+{
+public:
+    explicit Visitor(InstantiationData const & data): RewritePlugin(data) {}
+
+    void run() override {
+        if (compiler.getLangOpts().CPlusPlus) {
+            TraverseDecl(compiler.getASTContext().getTranslationUnitDecl());
+        }
+    }
+
+    bool VisitFunctionDecl(FunctionDecl const * decl) {
+        if (ignoreLocation(decl) || !decl->isInlineSpecified()
+            || !(decl->doesThisDeclarationHaveABody()
+                 || decl->isExplicitlyDefaulted())
+            || !(decl->getLexicalDeclContext()->isRecord()
+                 || decl->isConstexpr()))
+        {
+            return true;
+        }
+        auto l1 = unwindToQObject(decl->getLocStart());
+        if (l1.isValid() && l1 == unwindToQObject(decl->getLocEnd())) {
+            return true;
+        }
+        SourceLocation inlineLoc;
+        unsigned n;
+        auto end = Lexer::getLocForEndOfToken(
+            compiler.getSourceManager().getExpansionLoc(decl->getLocEnd()), 0,
+            compiler.getSourceManager(), compiler.getLangOpts());
+        assert(end.isValid());
+        for (auto loc = compiler.getSourceManager().getExpansionLoc(
+                 decl->getLocStart());
+             loc != end; loc = loc.getLocWithOffset(std::max<unsigned>(n, 1)))
+        {
+            n = Lexer::MeasureTokenLength(
+                loc, compiler.getSourceManager(), compiler.getLangOpts());
+            StringRef s(compiler.getSourceManager().getCharacterData(loc), n);
+            //TODO: see compilerplugins/clang/override.cxx:
+            if (s.startswith("\\\n")) {
+                s = s.drop_front(2);
+            }
+            if (s == "inline") {
+                if (!compiler.getSourceManager().isMacroArgExpansion(loc)) {
+                    inlineLoc = loc;
+                }
+                break;
+            } else if (s == "#") {
+                // Hard to pick the right 'inline' in code like
+                //
+                //   #if 1
+                //     static
+                //   #else
+                //     inline
+                //   #endif
+                //   inline void f() {}
+                //
+                // so just give up once a preprocessing directive is seen:
+                break;
+            }
+        }
+        if (rewriter != nullptr && inlineLoc.isValid()) {
+            for (auto loc = inlineLoc.getLocWithOffset(
+                     std::max<unsigned>(n, 1));;)
+            {
+                assert(loc != end);
+                unsigned n2 = Lexer::MeasureTokenLength(
+                    loc, compiler.getSourceManager(), compiler.getLangOpts());
+                StringRef s(
+                    compiler.getSourceManager().getCharacterData(loc), n2);
+                //TODO: see compilerplugins/clang/override.cxx:
+                if (s.startswith("\\\n")) {
+                    s = s.drop_front(2);
+                }
+                if (!s.empty()) {
+                    break;
+                }
+                n2 = std::max<unsigned>(n2, 1);
+                n += n2;
+                loc = loc.getLocWithOffset(n2);
+            }
+            if (removeText(inlineLoc, n, RewriteOptions(RemoveLineIfEmpty))) {
+                return true;
+            }
+        }
+        report(
+            DiagnosticsEngine::Warning,
+            "function definition redundantly declared 'inline'",
+            inlineLoc.isValid() ? inlineLoc : decl->getLocStart())
+            << decl->getSourceRange();
+        return true;
+    }
+
+private:
+    SourceLocation unwindToQObject(SourceLocation const & loc) {
+        if (!loc.isMacroID()) {
+            return SourceLocation();
+        }
+        auto l = compiler.getSourceManager().getImmediateMacroCallerLoc(loc);
+        return
+            (Lexer::getImmediateMacroName(
+                loc, compiler.getSourceManager(), compiler.getLangOpts())
+             == "Q_OBJECT")
+            ? l : unwindToQObject(l);
+    }
+};
+
+loplugin::Plugin::Registration<Visitor> reg("redundantinline", true);
+
+}
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab cinoptions=b1,g0,N-s cinkeys+=0=break: */
diff --git a/compilerplugins/clang/test/redundantinline.cxx b/compilerplugins/clang/test/redundantinline.cxx
new file mode 100644
index 000000000000..038a1497d98e
--- /dev/null
+++ b/compilerplugins/clang/test/redundantinline.cxx
@@ -0,0 +1,14 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4; fill-column: 100 -*- */
+/*
+ * 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 "redundantinline.hxx"
+
+S1::~S1() = default;
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab cinoptions=b1,g0,N-s cinkeys+=0=break: */
diff --git a/compilerplugins/clang/test/redundantinline.hxx b/compilerplugins/clang/test/redundantinline.hxx
new file mode 100644
index 000000000000..a0c91ceb67be
--- /dev/null
+++ b/compilerplugins/clang/test/redundantinline.hxx
@@ -0,0 +1,79 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4; fill-column: 100 -*- */
+/*
+ * 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/.
+ */
+
+#ifndef INCLUDED_COMPILERPLUGINS_CLANG_TEST_REDUNDANTINLINE_HXX
+#define INCLUDED_COMPILERPLUGINS_CLANG_TEST_REDUNDANTINLINE_HXX
+
+struct S1 {
+    inline S1();
+    inline ~S1();
+};
+
+S1::S1() = default;
+
+struct S2 {
+    inline S2() = default; // expected-error {{[loplugin:redundantinline]}}
+    inline ~S2() = default; // expected-error {{[loplugin:redundantinline]}} expected-error {{[loplugin:unnecessaryoverride]}}
+};
+
+struct S3 {
+    inline S3();
+    inline ~S3();
+
+    inline void f1();
+
+    static inline void f2();
+
+    inline void operator +();
+
+    inline operator int();
+
+    friend inline void f3();
+};
+
+S3::S3() {}
+
+S3::~S3() { f1(); }
+
+void S3::f1() { (void)this; }
+
+void S3::f2() {}
+
+void S3::operator +() {}
+
+void f3() {}
+
+S3::operator int() { return 0; }
+
+struct S4 {
+    inline S4() {} // expected-error {{[loplugin:redundantinline]}}
+    inline ~S4() { f1(); } // expected-error {{[loplugin:redundantinline]}}
+
+    inline void f1() { (void)this; } // expected-error {{[loplugin:redundantinline]}}
+
+    static inline void f2() {} // expected-error {{[loplugin:redundantinline]}}
+
+    inline void operator +() {} // expected-error {{[loplugin:redundantinline]}}
+
+    inline operator int() { return 0; } // expected-error {{[loplugin:redundantinline]}}
+
+    friend inline void f4() {} // expected-error {{[loplugin:redundantinline]}}
+
+    static constexpr int f5() { return 0; }
+
+    static constexpr inline int f6() { return 0; } // expected-error {{[loplugin:redundantinline]}}
+};
+
+constexpr int f5() { return 0; }
+
+constexpr inline int f6() { return 0; } // expected-error {{[loplugin:redundantinline]}}
+
+#endif
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab cinoptions=b1,g0,N-s cinkeys+=0=break: */