new loplugin convertuintptr

an experiment to see if I can make the process of eliminating
sal_uIntPtr a little easier

Change-Id: I808185fbf18826cb9ab5612a7be4148d52045957

3 files changed, 125 insertions, 2 deletions

diff --git a/compilerplugins/clang/convertuintptr.cxx b/compilerplugins/clang/convertuintptr.cxx
new file mode 100644
index 000000000000..77eb1b4f8616
--- /dev/null
+++ b/compilerplugins/clang/convertuintptr.cxx
@@ -0,0 +1,105 @@
+/* -*- 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 <memory>
+#include <cassert>
+#include <string>
+#include <iostream>
+#include <fstream>
+#include <set>
+#include "plugin.hxx"
+#include "check.hxx"
+
+/**
+  plugin to help to when converting code from sal_uIntPtr to something more precise.
+ */
+namespace {
+
+class ConvertUIntPtr:
+    public RecursiveASTVisitor<ConvertUIntPtr>, public loplugin::Plugin
+{
+public:
+    explicit ConvertUIntPtr(InstantiationData const & data): Plugin(data) {}
+
+    virtual void run() override
+    {
+        std::string fn( compiler.getSourceManager().getFileEntryForID(
+                        compiler.getSourceManager().getMainFileID())->getName() );
+        normalizeDotDotInFilePath(fn);
+        // using sal_uIntPtr as in-between type when converting void* to rtl_TextEncoding
+        if (fn == SRCDIR "/sal/osl/unx/thread.cxx")
+            return;
+        // too much magic
+        if (fn == SRCDIR "/sal/rtl/alloc_arena.cxx")
+            return;
+        if (fn == SRCDIR "/sal/rtl/alloc_cache.cxx")
+            return;
+        // TODO not sure what is going on here
+        if (fn == SRCDIR "/tools/source/generic/bigint.cxx")
+            return;
+        TraverseDecl(compiler.getASTContext().getTranslationUnitDecl());
+    }
+
+    bool VisitImplicitCastExpr(ImplicitCastExpr const *);
+private:
+    bool isIntPtr(QualType qt);
+};
+
+bool ConvertUIntPtr::VisitImplicitCastExpr(ImplicitCastExpr const * castExpr)
+{
+    if (ignoreLocation(castExpr))
+        return true;
+
+    if (castExpr->getCastKind() == CK_LValueToRValue)
+        return true;
+    if (isa<IntegerLiteral>(castExpr->IgnoreCasts()))
+        return true;
+    // ignore literals like "-123"
+    if (isa<UnaryOperator>(castExpr->IgnoreCasts()))
+        return true;
+
+    bool isSrcIntPtr = isIntPtr(castExpr->getSubExpr()->getType());
+    bool isDestIntPtr = isIntPtr(castExpr->getType());
+
+    if (!isSrcIntPtr && !isDestIntPtr)
+        return true;
+
+    // exclude casting between sal_uIntPtr <-> sal_IntPtr
+    if (isSrcIntPtr && isDestIntPtr)
+        return true;
+
+    if (isSrcIntPtr && loplugin::TypeCheck(castExpr->getType()).AnyBoolean())
+        return true;
+
+    report(
+        DiagnosticsEngine::Warning,
+        "cast from %0 to %1",
+        castExpr->getExprLoc())
+      << castExpr->getSubExpr()->getType()
+      << castExpr->getType()
+      << castExpr->getSourceRange();
+
+    return true;
+}
+
+bool ConvertUIntPtr::isIntPtr(QualType qt)
+{
+    auto tc = loplugin::TypeCheck(qt);
+    if (!tc.Typedef())
+        return false;
+    TypedefType const * typedefType = qt->getAs<TypedefType>();
+    auto name = typedefType->getDecl()->getName();
+    return name == "sal_uIntPtr" || name == "sal_IntPtr";
+}
+
+loplugin::Plugin::Registration< ConvertUIntPtr > X("convertuintptr", false);
+
+}
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/compilerplugins/clang/droplong.cxx b/compilerplugins/clang/droplong.cxx
index a6ef33006d9d..fe5675b36d2f 100644
--- a/compilerplugins/clang/droplong.cxx
+++ b/compilerplugins/clang/droplong.cxx
@@ -57,8 +57,6 @@ public:
         TraverseDecl(compiler.getASTContext().getTranslationUnitDecl());
     }
 
-    bool shouldVisitTemplateInstantiations () const { return true; }
-
     bool VisitBinAssign(BinaryOperator const *);
     bool VisitVarDecl(VarDecl const *);
     bool VisitCastExpr(CastExpr const *);
diff --git a/compilerplugins/clang/test/convertuintptr.cxx b/compilerplugins/clang/test/convertuintptr.cxx
new file mode 100644
index 000000000000..8789394c541f
--- /dev/null
+++ b/compilerplugins/clang/test/convertuintptr.cxx
@@ -0,0 +1,20 @@
+/* -*- 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 <tools/solar.h>
+
+int main()
+{
+    sal_uIntPtr x = 1;
+    sal_uInt32 y = x; // expected-error {{cast from 'sal_uIntPtr' (aka 'unsigned long') to 'sal_uInt32' (aka 'unsigned int') [loplugin:convertuintptr]}}
+    y = x; // expected-error {{cast from 'sal_uIntPtr' (aka 'unsigned long') to 'sal_uInt32' (aka 'unsigned int') [loplugin:convertuintptr]}}
+    (void)y;
+}
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab cinoptions=b1,g0,N-s cinkeys+=0=break: */