Improve loplugin:redundantpreprocessor performance a bit

...and add a minimal test for it

Change-Id: Ia6c61e41a7e60fd01c639e893c34bd9d215c1513
Reviewed-on: https://gerrit.libreoffice.org/82983
Tested-by: Jenkins
Reviewed-by: Stephan Bergmann <sbergman@redhat.com>

3 files changed, 20 insertions, 4 deletions

diff --git a/compilerplugins/clang/readability-redundant-pp.cxx b/compilerplugins/clang/readability-redundant-pp.cxx
index e1c284b99c63..dcfd70247ff8 100644
--- a/compilerplugins/clang/readability-redundant-pp.cxx
+++ b/compilerplugins/clang/readability-redundant-pp.cxx
@@ -69,9 +69,9 @@ void RedundantPreprocessor::Ifdef(clang::SourceLocation aLoc, const clang::Token
     if (ignoreLocation(aLoc))
         return;
 
+    std::string aMacroName = m_rPP.getSpelling(rMacroNameTok);
     if (m_rPP.getSourceManager().isInMainFile(aLoc))
     {
-        std::string aMacroName = m_rPP.getSpelling(rMacroNameTok);
         for (const auto& rEntry : m_aDefStack)
         {
             if (rEntry.m_aMacroName == aMacroName)
@@ -84,7 +84,7 @@ void RedundantPreprocessor::Ifdef(clang::SourceLocation aLoc, const clang::Token
 
     Entry aEntry;
     aEntry.m_aLoc = aLoc;
-    aEntry.m_aMacroName = m_rPP.getSpelling(rMacroNameTok);
+    aEntry.m_aMacroName = aMacroName;
     m_aDefStack.push_back(aEntry);
 }
 
@@ -94,9 +94,9 @@ void RedundantPreprocessor::Ifndef(clang::SourceLocation aLoc, const clang::Toke
     if (ignoreLocation(aLoc))
         return;
 
+    std::string aMacroName = m_rPP.getSpelling(rMacroNameTok);
     if (m_rPP.getSourceManager().isInMainFile(aLoc))
     {
-        std::string aMacroName = m_rPP.getSpelling(rMacroNameTok);
         for (const auto& rEntry : m_aNotDefStack)
         {
             if (rEntry.m_aMacroName == aMacroName)
@@ -109,7 +109,7 @@ void RedundantPreprocessor::Ifndef(clang::SourceLocation aLoc, const clang::Toke
 
     Entry aEntry;
     aEntry.m_aLoc = aLoc;
-    aEntry.m_aMacroName = m_rPP.getSpelling(rMacroNameTok);
+    aEntry.m_aMacroName = aMacroName;
     m_aNotDefStack.push_back(aEntry);
 }
 
diff --git a/compilerplugins/clang/test/redundantpreprocessor.cxx b/compilerplugins/clang/test/redundantpreprocessor.cxx
new file mode 100644
index 000000000000..18ab10559f67
--- /dev/null
+++ b/compilerplugins/clang/test/redundantpreprocessor.cxx
@@ -0,0 +1,15 @@
+/* -*- 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/.
+ */
+
+#ifdef __clang__ // expected-note {{previous ifdef [loplugin:redundantpreprocessor]}}
+#ifdef __clang__ // expected-error {{nested ifdef [loplugin:redundantpreprocessor]}}
+#endif
+#endif
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab cinoptions=b1,g0,N-s cinkeys+=0=break: */
diff --git a/solenv/CompilerTest_compilerplugins_clang.mk b/solenv/CompilerTest_compilerplugins_clang.mk
index 226d0686dd52..e429d1bc00fa 100644
--- a/solenv/CompilerTest_compilerplugins_clang.mk
+++ b/solenv/CompilerTest_compilerplugins_clang.mk
@@ -59,6 +59,7 @@ $(eval $(call gb_CompilerTest_add_exception_objects,compilerplugins_clang, \
     compilerplugins/clang/test/redundantfcast \
     compilerplugins/clang/test/redundantinline \
     compilerplugins/clang/test/redundantpointerops \
+    compilerplugins/clang/test/redundantpreprocessor \
     compilerplugins/clang/test/refcounting \
     compilerplugins/clang/test/referencecasting \
     compilerplugins/clang/test/returnconstval \