summaryrefslogtreecommitdiffstats
path: root/compilerplugins/clang/unusedfieldsremove.cxx
diff options
context:
space:
mode:
Diffstat (limited to 'compilerplugins/clang/unusedfieldsremove.cxx')
-rw-r--r--compilerplugins/clang/unusedfieldsremove.cxx136
1 files changed, 136 insertions, 0 deletions
diff --git a/compilerplugins/clang/unusedfieldsremove.cxx b/compilerplugins/clang/unusedfieldsremove.cxx
new file mode 100644
index 000000000..b8c339edc
--- /dev/null
+++ b/compilerplugins/clang/unusedfieldsremove.cxx
@@ -0,0 +1,136 @@
+/* -*- 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/.
+ */
+
+#if !defined _WIN32 //TODO, #include <sys/mman.h>
+
+#include <cassert>
+#include <string>
+#include <iostream>
+#include "plugin.hxx"
+#include <sys/mman.h>
+#include <sys/types.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <sys/stat.h>
+#include <assert.h>
+#include <cstring>
+
+/**
+ This is intended to be run as the second stage of the "unusedfields" clang plugin.
+*/
+
+namespace {
+
+class UnusedFieldsRemove:
+ public loplugin::FilteringRewritePlugin<UnusedFieldsRemove>
+{
+public:
+ explicit UnusedFieldsRemove(loplugin::InstantiationData const & data);
+ ~UnusedFieldsRemove();
+
+ virtual void run() override { TraverseDecl(compiler.getASTContext().getTranslationUnitDecl()); }
+
+ bool VisitFieldDecl( const FieldDecl* var );
+private:
+ // I use a brute-force approach - mmap the results file and do a linear search on it
+ // It works surprisingly well, because the file is small enough to fit into L2 cache on modern CPU's
+ size_t mmapFilesize;
+ int mmapFD;
+ char* mmappedData;
+};
+
+size_t getFilesize(const char* filename)
+{
+ struct stat st;
+ stat(filename, &st);
+ return st.st_size;
+}
+
+UnusedFieldsRemove::UnusedFieldsRemove(loplugin::InstantiationData const & data): FilteringRewritePlugin(data)
+{
+ static const char sInputFile[] = SRCDIR "/result.txt";
+ mmapFilesize = getFilesize(sInputFile);
+ //Open file
+ mmapFD = open(sInputFile, O_RDONLY, 0);
+ assert(mmapFD != -1);
+ //Execute mmap
+ mmappedData = static_cast<char*>(mmap(NULL, mmapFilesize, PROT_READ, MAP_PRIVATE, mmapFD, 0));
+ assert(mmappedData != NULL);
+}
+
+UnusedFieldsRemove::~UnusedFieldsRemove()
+{
+ //Cleanup
+ int rc = munmap(mmappedData, mmapFilesize);
+ assert(rc == 0);
+ (void)rc;
+ close(mmapFD);
+}
+
+std::string niceName(const FieldDecl* fieldDecl)
+{
+ return fieldDecl->getParent()->getQualifiedNameAsString() + " " +
+ fieldDecl->getNameAsString();
+}
+
+bool UnusedFieldsRemove::VisitFieldDecl( const FieldDecl* fieldDecl )
+{
+ if (rewriter == nullptr) {
+ return true;
+ }
+ if (ignoreLocation(fieldDecl)) {
+ return true;
+ }
+ // ignore stuff that forms part of the stable URE interface
+ if (isInUnoIncludeFile(compiler.getSourceManager().getSpellingLoc(
+ fieldDecl->getCanonicalDecl()->getLocation()))) {
+ return true;
+ }
+
+ // don't mess with templates
+/* if (isa<CXXRecordDecl>(fieldDecl->getParent())) {
+ if (dyn_cast<CXXRecordDecl>(fieldDecl->getParent())->getDescribedClassTemplate() != nullptr) {
+ return true;
+ }
+ }
+*/
+ std::string aNiceName = " " + niceName(fieldDecl) + "\n";
+ const char *aNiceNameStr = aNiceName.c_str();
+ char* found = std::search(mmappedData, mmappedData + mmapFilesize, aNiceNameStr, aNiceNameStr + strlen(aNiceNameStr));
+ if(!(found < mmappedData + mmapFilesize)) {
+ return true;
+ }
+ SourceRange replaceRange(fieldDecl->getSourceRange());
+ // sometimes the declaration has a semicolon just after it, and it's much neater to remove that too.
+ if (rewriter->getRewrittenText(SourceRange(replaceRange.getEnd(), replaceRange.getEnd().getLocWithOffset(1))) == ";") {
+ replaceRange.setEnd(replaceRange.getEnd().getLocWithOffset(1));
+ }
+ // remove leading spaces
+ while (rewriter->getRewrittenText(SourceRange(replaceRange.getBegin().getLocWithOffset(-1), replaceRange.getBegin())) == " ")
+ {
+ replaceRange.setBegin(replaceRange.getBegin().getLocWithOffset(-1));
+ }
+ if (!replaceText(replaceRange, "")) {
+ report(
+ DiagnosticsEngine::Warning,
+ "Could not remove unused field (" + niceName(fieldDecl) + ")",
+ compat::getBeginLoc(fieldDecl))
+ << fieldDecl->getSourceRange();
+ }
+ return true;
+}
+
+
+loplugin::Plugin::Registration< UnusedFieldsRemove > X("unusedfieldsremove", false);
+
+}
+
+#endif
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */