[test] Fix plugin tests

Recommit of r361790 that was temporarily reverted in r361793 due to bot breakage.

Summary:
The following changes were required to fix these tests:

1) Change LLVM_ENABLE_PLUGINS to an option and move it to
   llvm/CMakeLists.txt with an appropriate default -- which matches
   the original default behavior.

2) Move the plugins directory from clang/test/Analysis
   clang/lib/Analysis.  It's not enough to add an exclude to the
   lit.local.cfg file because add_lit_testsuites recurses the tree and
   automatically adds the appropriate `check-` targets, which don't
   make sense for the plugins because they aren't tests and don't
   have `RUN` statements.

   Here's a list of the `clang-check-anlysis*` targets with this
   change:

```
  $ ninja -t targets all| sed -n "s/.*\/\(check[^:]*\):.*/\1/p" | sort -u | grep clang-analysis
  check-clang-analysis
  check-clang-analysis-checkers
  check-clang-analysis-copypaste
  check-clang-analysis-diagnostics
  check-clang-analysis-engine
  check-clang-analysis-exploration_order
  check-clang-analysis-html_diagnostics
  check-clang-analysis-html_diagnostics-relevant_lines
  check-clang-analysis-inlining
  check-clang-analysis-objc
  check-clang-analysis-unified-sources
  check-clang-analysis-z3
```

3) Simplify the logic and only include the subdirectories under
   clang/lib/Analysis/plugins if LLVM_ENABLE_PLUGINS is set.

Reviewed By: NoQ

Tags: #clang, #llvm

Differential Revision: https://reviews.llvm.org/D62445

llvm-svn: 362328

3 files changed, 56 insertions, 0 deletions

diff --git a/clang/lib/Analysis/plugins/CheckerOptionHandling/CMakeLists.txt b/clang/lib/Analysis/plugins/CheckerOptionHandling/CMakeLists.txt
new file mode 100644
index 00000000000..6e289933c2d
--- /dev/null
+++ b/clang/lib/Analysis/plugins/CheckerOptionHandling/CMakeLists.txt
@@ -0,0 +1,10 @@
+set(LLVM_EXPORTED_SYMBOL_FILE ${CMAKE_CURRENT_SOURCE_DIR}/CheckerOptionHandlingAnalyzerPlugin.exports)
+add_llvm_library(CheckerOptionHandlingAnalyzerPlugin MODULE CheckerOptionHandling.cpp PLUGIN_TOOL clang)
+
+target_link_libraries(CheckerOptionHandlingAnalyzerPlugin PRIVATE
+  clangAnalysis
+  clangAST
+  clangStaticAnalyzerCore
+  clangStaticAnalyzerFrontend
+  LLVMSupport
+  )
diff --git a/clang/lib/Analysis/plugins/CheckerOptionHandling/CheckerOptionHandling.cpp b/clang/lib/Analysis/plugins/CheckerOptionHandling/CheckerOptionHandling.cpp
new file mode 100644
index 00000000000..77de3630ae7
--- /dev/null
+++ b/clang/lib/Analysis/plugins/CheckerOptionHandling/CheckerOptionHandling.cpp
@@ -0,0 +1,44 @@
+#include "clang/StaticAnalyzer/Core/BugReporter/BugType.h"
+#include "clang/StaticAnalyzer/Core/Checker.h"
+#include "clang/StaticAnalyzer/Core/PathSensitive/CheckerContext.h"
+#include "clang/StaticAnalyzer/Frontend/CheckerRegistry.h"
+
+using namespace clang;
+using namespace ento;
+
+namespace {
+struct MyChecker : public Checker<check::BeginFunction> {
+  void checkBeginFunction(CheckerContext &Ctx) const {}
+};
+
+void registerMyChecker(CheckerManager &Mgr) {
+  MyChecker *Checker = Mgr.registerChecker<MyChecker>();
+  llvm::outs() << "Example option is set to "
+               << (Mgr.getAnalyzerOptions().getCheckerBooleanOption(
+                       Checker, "ExampleOption")
+                       ? "true"
+                       : "false")
+               << '\n';
+}
+
+bool shouldRegisterMyChecker(const LangOptions &LO) { return true; }
+
+} // end anonymous namespace
+
+// Register plugin!
+extern "C" void clang_registerCheckers(CheckerRegistry &registry) {
+  registry.addChecker(registerMyChecker, shouldRegisterMyChecker,
+                      "example.MyChecker", "Example Description",
+                      "example.mychecker.documentation.nonexistent.html",
+                      /*isHidden*/false);
+
+  registry.addCheckerOption(/*OptionType*/ "bool",
+                            /*CheckerFullName*/ "example.MyChecker",
+                            /*OptionName*/ "ExampleOption",
+                            /*DefaultValStr*/ "false",
+                            /*Description*/ "This is an example checker opt.",
+                            /*DevelopmentStage*/ "released");
+}
+
+extern "C" const char clang_analyzerAPIVersionString[] =
+    CLANG_ANALYZER_API_VERSION_STRING;
diff --git a/clang/lib/Analysis/plugins/CheckerOptionHandling/CheckerOptionHandlingAnalyzerPlugin.exports b/clang/lib/Analysis/plugins/CheckerOptionHandling/CheckerOptionHandlingAnalyzerPlugin.exports
new file mode 100644
index 00000000000..8d9ff882cfb
--- /dev/null
+++ b/clang/lib/Analysis/plugins/CheckerOptionHandling/CheckerOptionHandlingAnalyzerPlugin.exports
@@ -0,0 +1,2 @@
+clang_registerCheckers
+clang_analyzerAPIVersionString