[PATCH] D106137: [flang][driver] Add support for Frontend Plugins

2021-07-16 Thread Stuart Ellis via Phabricator via cfe-commits 
stuartellis created this revision.
Herald added subscribers: dang, mgorny.
Herald added a reviewer: sscalpone.
Herald added a reviewer: awarzynski.
stuartellis requested review of this revision.
Herald added a project: clang.
Herald added a subscriber: cfe-commits.

Introducing a plugin API and a simple HelloWorld Plugin example.
This patch adds the `-load` and `-plugin` flags to frontend driver and
the code around using custom frontend actions from within a plugin
shared library object.

It also adds to the Driver-help test to check the help option with the
updated driver flags.

Additionally, the patch creates a plugin-example test to check the
HelloWorld plugin example runs correctly. As part of this, a new CMake
flag (FLANG_BUILD_EXAMPLES) is added to allow the example to be built
and for the test to run.


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D106137

Files:
  clang/include/clang/Driver/Options.td
  flang/CMakeLists.txt
  flang/examples/CMakeLists.txt
  flang/examples/HelloWorld/CMakeLists.txt
  flang/examples/HelloWorld/HelloWorldPlugin.cpp
  flang/include/flang/Frontend/FrontendActions.h
  flang/include/flang/Frontend/FrontendOptions.h
  flang/include/flang/Frontend/FrontendPluginRegistry.h
  flang/lib/Frontend/CompilerInvocation.cpp
  flang/lib/Frontend/FrontendAction.cpp
  flang/lib/Frontend/FrontendActions.cpp
  flang/lib/FrontendTool/ExecuteCompilerInvocation.cpp
  flang/test/CMakeLists.txt
  flang/test/Driver/driver-help.f90
  flang/test/Driver/plugin-example.f90
  flang/test/lit.cfg.py
  flang/test/lit.site.cfg.py.in
  flang/tools/flang-driver/CMakeLists.txt

Index: flang/tools/flang-driver/CMakeLists.txt
===
--- flang/tools/flang-driver/CMakeLists.txt
+++ flang/tools/flang-driver/CMakeLists.txt
@@ -27,4 +27,6 @@
   clangBasic
 )
 
+export_executable_symbols_for_plugins(flang-new)
+
 install(TARGETS flang-new DESTINATION bin)
Index: flang/test/lit.site.cfg.py.in
===
--- flang/test/lit.site.cfg.py.in
+++ flang/test/lit.site.cfg.py.in
@@ -3,6 +3,8 @@
 import sys
 
 config.llvm_tools_dir = "@LLVM_TOOLS_DIR@"
+config.llvm_shlib_dir = path(r"@SHLIBDIR@")
+config.llvm_plugin_ext = "@LLVM_PLUGIN_EXT@"
 config.lit_tools_dir = "@LLVM_LIT_TOOLS_DIR@"
 config.flang_obj_root = "@FLANG_BINARY_DIR@"
 config.flang_src_dir = "@FLANG_SOURCE_DIR@"
@@ -10,8 +12,10 @@
 config.flang_intrinsic_modules_dir = "@FLANG_INTRINSIC_MODULES_DIR@"
 config.flang_llvm_tools_dir = "@CMAKE_BINARY_DIR@/bin"
 config.flang_lib_dir = "@CMAKE_BINARY_DIR@/lib"
+config.flang_examples = @FLANG_BUILD_EXAMPLES@
 config.python_executable = "@PYTHON_EXECUTABLE@"
 config.flang_standalone_build = @FLANG_STANDALONE_BUILD@
+config.has_plugins = @LLVM_ENABLE_PLUGINS@
 config.cc = "@CMAKE_C_COMPILER@"
 
 # Control the regression test for flang-new driver
@@ -24,6 +28,7 @@
 try:
 config.llvm_tools_dir = config.llvm_tools_dir % lit_config.params
 config.flang_tools_dir = config.flang_tools_dir % lit_config.params
+config.llvm_shlib_dir = config.llvm_shlib_dir % lit_config.params
 except KeyError:
 e = sys.exc_info()[1]
 key, = e.args
Index: flang/test/lit.cfg.py
===
--- flang/test/lit.cfg.py
+++ flang/test/lit.cfg.py
@@ -30,6 +30,8 @@
'.CUF', '.f18', '.F18', '.fir', '.f03', '.F03', '.f08', '.F08']
 
 config.substitutions.append(('%PATH%', config.environment['PATH']))
+config.substitutions.append(('%llvmshlibdir', config.llvm_shlib_dir))
+config.substitutions.append(('%pluginext', config.llvm_plugin_ext))
 
 llvm_config.use_default_substitutions()
 
@@ -45,6 +47,14 @@
 else:
   config.available_features.add('old-flang-driver')
 
+# If the flang examples are built, add examples to the config
+if config.flang_examples:
+config.available_features.add('examples')
+
+# Plugins (loadable modules)
+if config.has_plugins and config.llvm_plugin_ext:
+config.available_features.add('plugins')
+
 # test_source_root: The root path where tests are located.
 config.test_source_root = os.path.dirname(__file__)
 
Index: flang/test/Driver/plugin-example.f90
===
--- /dev/null
+++ flang/test/Driver/plugin-example.f90
@@ -0,0 +1,7 @@
+! Check that loading and running the Hello World plugin example results in the correct print statement
+! This requires that the examples are built (FLANG_BUILD_EXAMPLES=ON)
+
+! REQUIRES: new-flang-driver, plugins, examples
+
+! RUN: %flang_fc1 -load %llvmshlibdir/flangHelloWorldPlugin%pluginext -plugin -hello-world %s 2>&1 | FileCheck %s
+! CHECK: Hello World from your new plugin
Index: flang/test/Driver/driver-help.f90
===
--- flang/test/Driver/driver-help.f90
+++ flang/test/Driver/driver-help.f90
@@ -109,11 +109,13 @@
 ! HELP-FC1-NEXT: -help

[PATCH] D106137: [flang][driver] Add support for Frontend Plugins

2021-07-22 Thread Stuart Ellis via Phabricator via cfe-commits 
stuartellis updated this revision to Diff 360887.
stuartellis added a comment.

Address review comments
Added some comments to a couple of places
Added new `FLANG_PLUGIN_SUPPORT` CMake flag to control exporting executable 
symbols


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D106137/new/

https://reviews.llvm.org/D106137

Files:
  clang/include/clang/Driver/Options.td
  flang/CMakeLists.txt
  flang/examples/CMakeLists.txt
  flang/examples/HelloWorld/CMakeLists.txt
  flang/examples/HelloWorld/HelloWorldPlugin.cpp
  flang/include/flang/Frontend/FrontendActions.h
  flang/include/flang/Frontend/FrontendOptions.h
  flang/include/flang/Frontend/FrontendPluginRegistry.h
  flang/lib/Frontend/CompilerInvocation.cpp
  flang/lib/Frontend/FrontendAction.cpp
  flang/lib/Frontend/FrontendActions.cpp
  flang/lib/FrontendTool/ExecuteCompilerInvocation.cpp
  flang/test/CMakeLists.txt
  flang/test/Driver/driver-help.f90
  flang/test/Driver/plugin-example.f90
  flang/test/lit.cfg.py
  flang/test/lit.site.cfg.py.in
  flang/tools/flang-driver/CMakeLists.txt

Index: flang/tools/flang-driver/CMakeLists.txt
===
--- flang/tools/flang-driver/CMakeLists.txt
+++ flang/tools/flang-driver/CMakeLists.txt
@@ -27,4 +27,11 @@
   clangBasic
 )
 
+option(FLANG_PLUGIN_SUPPORT "Build Flang with plugin support." ON)
+
+# Enable support for plugins, which need access to symbols from flang-new
+if(FLANG_PLUGIN_SUPPORT)
+  export_executable_symbols_for_plugins(flang-new)
+endif()
+
 install(TARGETS flang-new DESTINATION bin)
Index: flang/test/lit.site.cfg.py.in
===
--- flang/test/lit.site.cfg.py.in
+++ flang/test/lit.site.cfg.py.in
@@ -3,6 +3,8 @@
 import sys
 
 config.llvm_tools_dir = "@LLVM_TOOLS_DIR@"
+config.llvm_shlib_dir = path(r"@SHLIBDIR@")
+config.llvm_plugin_ext = "@LLVM_PLUGIN_EXT@"
 config.lit_tools_dir = "@LLVM_LIT_TOOLS_DIR@"
 config.flang_obj_root = "@FLANG_BINARY_DIR@"
 config.flang_src_dir = "@FLANG_SOURCE_DIR@"
@@ -10,8 +12,10 @@
 config.flang_intrinsic_modules_dir = "@FLANG_INTRINSIC_MODULES_DIR@"
 config.flang_llvm_tools_dir = "@CMAKE_BINARY_DIR@/bin"
 config.flang_lib_dir = "@CMAKE_BINARY_DIR@/lib"
+config.flang_examples = @FLANG_BUILD_EXAMPLES@
 config.python_executable = "@PYTHON_EXECUTABLE@"
 config.flang_standalone_build = @FLANG_STANDALONE_BUILD@
+config.has_plugins = @LLVM_ENABLE_PLUGINS@
 config.cc = "@CMAKE_C_COMPILER@"
 
 # Control the regression test for flang-new driver
@@ -24,6 +28,7 @@
 try:
 config.llvm_tools_dir = config.llvm_tools_dir % lit_config.params
 config.flang_tools_dir = config.flang_tools_dir % lit_config.params
+config.llvm_shlib_dir = config.llvm_shlib_dir % lit_config.params
 except KeyError:
 e = sys.exc_info()[1]
 key, = e.args
Index: flang/test/lit.cfg.py
===
--- flang/test/lit.cfg.py
+++ flang/test/lit.cfg.py
@@ -30,6 +30,8 @@
'.CUF', '.f18', '.F18', '.fir', '.f03', '.F03', '.f08', '.F08']
 
 config.substitutions.append(('%PATH%', config.environment['PATH']))
+config.substitutions.append(('%llvmshlibdir', config.llvm_shlib_dir))
+config.substitutions.append(('%pluginext', config.llvm_plugin_ext))
 
 llvm_config.use_default_substitutions()
 
@@ -45,6 +47,14 @@
 else:
   config.available_features.add('old-flang-driver')
 
+# If the flang examples are built, add examples to the config
+if config.flang_examples:
+config.available_features.add('examples')
+
+# Plugins (loadable modules)
+if config.has_plugins:
+config.available_features.add('plugins')
+
 # test_source_root: The root path where tests are located.
 config.test_source_root = os.path.dirname(__file__)
 
Index: flang/test/Driver/plugin-example.f90
===
--- /dev/null
+++ flang/test/Driver/plugin-example.f90
@@ -0,0 +1,11 @@
+! Check that loading and running the Hello World plugin example results in the correct print statement
+! Also check that when a plugin name isn't found, the error diagnostic is correct
+! This requires that the examples are built (FLANG_BUILD_EXAMPLES=ON)
+
+! REQUIRES: new-flang-driver, plugins, examples, shell
+
+! RUN: %flang_fc1 -load %llvmshlibdir/flangHelloWorldPlugin%pluginext -plugin -hello-world %s 2>&1 | FileCheck %s
+! CHECK: Hello World from your new Flang plugin
+
+! RUN: not %flang_fc1 -load %llvmshlibdir/flangHelloWorldPlugin%pluginext -plugin -wrong-name %s 2>&1 | FileCheck %s --check-prefix=ERROR
+! ERROR: error: unable to find plugin '-wrong-name'
Index: flang/test/Driver/driver-help.f90
===
--- flang/test/Driver/driver-help.f90
+++ flang/test/Driver/driver-help.f90
@@ -109,11 +109,13 @@
 ! HELP-FC1-NEXT: -help  Display available options
 ! HELP-FC1-NEXT: -init-only

[PATCH] D106137: [flang][driver] Add support for Frontend Plugins

2021-07-22 Thread Stuart Ellis via Phabricator via cfe-commits 
stuartellis marked 9 inline comments as done.
stuartellis added inline comments.



Comment at: flang/lib/FrontendTool/ExecuteCompilerInvocation.cpp:92
+unsigned diagID = ci.diagnostics().getCustomDiagID(
+clang::DiagnosticsEngine::Error, "unable to find plugin '%0'");
+ci.diagnostics().Report(diagID) << ci.frontendOpts().ActionName;

awarzynski wrote:
> Could you add a test for this diagnostic?
Added diagnostic test to the end of plugin-example.f90 test


Repository:
  rG LLVM Github Monorepo

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[PATCH] D102849: [flang][driver] Add support for the "-init-only" option

2021-05-20 Thread Stuart Ellis via Phabricator via cfe-commits 
stuartellis created this revision.
Herald added a reviewer: sscalpone.
Herald added a subscriber: dang.
Herald added a reviewer: awarzynski.
stuartellis requested review of this revision.
Herald added a project: clang.
Herald added a subscriber: cfe-commits.

Adding the -init-only option and corresponding frontend action
to generate a diagnostic.

It also adds a Driver test to check this action.


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D102849

Files:
  clang/include/clang/Driver/Options.td
  flang/include/flang/Frontend/FrontendActions.h
  flang/include/flang/Frontend/FrontendOptions.h
  flang/lib/Frontend/CompilerInvocation.cpp
  flang/lib/Frontend/FrontendActions.cpp
  flang/lib/FrontendTool/ExecuteCompilerInvocation.cpp
  flang/test/Driver/driver-help.f90
  flang/test/Driver/init-only.f90

Index: flang/test/Driver/init-only.f90
===
--- /dev/null
+++ flang/test/Driver/init-only.f90
@@ -0,0 +1,5 @@
+! Verify that -init-only flag generates a diagnostic as expected
+
+! RUN: %flang_fc1 -init-only 2>&1 | FileCheck %s
+
+! CHECK: warning: Use `-init-only` for testing purposes only
Index: flang/test/Driver/driver-help.f90
===
--- flang/test/Driver/driver-help.f90
+++ flang/test/Driver/driver-help.f90
@@ -104,6 +104,7 @@
 ! HELP-FC1-NEXT: -fopenmp   Parse OpenMP pragmas and generate parallel code.
 ! HELP-FC1-NEXT: -fxor-operator Enable .XOR. as a synonym of .NEQV.
 ! HELP-FC1-NEXT: -help  Display available options
+! HELP-FC1-NEXT: -init-only Only execute frontend initialization
 ! HELP-FC1-NEXT: -IAdd directory to the end of the list of include search paths
 ! HELP-FC1-NEXT: -module-dir   Put MODULE files in 
 ! HELP-FC1-NEXT: -nocpp Disable predefined and command line preprocessor macros
Index: flang/lib/FrontendTool/ExecuteCompilerInvocation.cpp
===
--- flang/lib/FrontendTool/ExecuteCompilerInvocation.cpp
+++ flang/lib/FrontendTool/ExecuteCompilerInvocation.cpp
@@ -73,6 +73,9 @@
   case GetSymbolsSources:
 return std::make_unique();
 break;
+  case InitializationOnly:
+return std::make_unique();
+break;
   default:
 break;
 // TODO:
Index: flang/lib/Frontend/FrontendActions.cpp
===
--- flang/lib/Frontend/FrontendActions.cpp
+++ flang/lib/Frontend/FrontendActions.cpp
@@ -447,3 +447,11 @@
   clang::DiagnosticsEngine::Error, "code-generation is not available yet");
   ci.diagnostics().Report(DiagID);
 }
+
+void InitializationOnlyAction::ExecuteAction() {
+  CompilerInstance &ci = this->instance();
+  unsigned DiagID =
+  ci.diagnostics().getCustomDiagID(clang::DiagnosticsEngine::Warning,
+  "Use `-init-only` for testing purposes only");
+  ci.diagnostics().Report(DiagID);
+}
Index: flang/lib/Frontend/CompilerInvocation.cpp
===
--- flang/lib/Frontend/CompilerInvocation.cpp
+++ flang/lib/Frontend/CompilerInvocation.cpp
@@ -162,9 +162,12 @@
 case clang::driver::options::OPT_fget_definition:
   opts.programAction_ = GetDefinition;
   break;
+case clang::driver::options::OPT_init_only:
+  opts.programAction_ = InitializationOnly;
+  break;
 
   // TODO:
-  // case calng::driver::options::OPT_emit_llvm:
+  // case clang::driver::options::OPT_emit_llvm:
   // case clang::driver::options::OPT_emit_llvm_only:
   // case clang::driver::options::OPT_emit_codegen_only:
   // case clang::driver::options::OPT_emit_module:
Index: flang/include/flang/Frontend/FrontendOptions.h
===
--- flang/include/flang/Frontend/FrontendOptions.h
+++ flang/include/flang/Frontend/FrontendOptions.h
@@ -71,7 +71,10 @@
   GetDefinition,
 
   /// Parse, run semantics and then dump symbol sources map
-  GetSymbolsSources
+  GetSymbolsSources,
+
+  /// Only execute frontend initialization
+  InitializationOnly
 
   /// TODO: RunPreprocessor, EmitLLVM, EmitLLVMOnly,
   /// EmitCodeGenOnly, EmitAssembly, (...)
Index: flang/include/flang/Frontend/FrontendActions.h
===
--- flang/include/flang/Frontend/FrontendActions.h
+++ flang/include/flang/Frontend/FrontendActions.h
@@ -38,6 +38,10 @@
   void ExecuteAction() override;
 };
 
+class InitializationOnlyAction : public FrontendAction {
+  void ExecuteAction() override;
+};
+
 //===--===//
 // Prescan Actions
 //===--===//
Index: clang/include/clang/Driver/Options.td
===
---

[PATCH] D102849: [flang][driver] Add support for the "-init-only" option

2021-06-02 Thread Stuart Ellis via Phabricator via cfe-commits 
stuartellis updated this revision to Diff 349307.
stuartellis added a comment.

Address review comments
Renaming InitializationOnly to InitOnly
Add missing line in init-only.f90
Updating commit message with init-only/test-io comparison


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D102849/new/

https://reviews.llvm.org/D102849

Files:
  clang/include/clang/Driver/Options.td
  flang/include/flang/Frontend/FrontendActions.h
  flang/include/flang/Frontend/FrontendOptions.h
  flang/lib/Frontend/CompilerInvocation.cpp
  flang/lib/Frontend/FrontendActions.cpp
  flang/lib/FrontendTool/ExecuteCompilerInvocation.cpp
  flang/test/Driver/driver-help.f90
  flang/test/Driver/init-only.f90

Index: flang/test/Driver/init-only.f90
===
--- /dev/null
+++ flang/test/Driver/init-only.f90
@@ -0,0 +1,7 @@
+! Verify that -init-only flag generates a diagnostic as expected
+
+! REQUIRES: new-flang-driver
+
+! RUN: %flang_fc1 -init-only 2>&1 | FileCheck %s
+
+! CHECK: warning: Use `-init-only` for testing purposes only
Index: flang/test/Driver/driver-help.f90
===
--- flang/test/Driver/driver-help.f90
+++ flang/test/Driver/driver-help.f90
@@ -104,6 +104,7 @@
 ! HELP-FC1-NEXT: -fopenmp   Parse OpenMP pragmas and generate parallel code.
 ! HELP-FC1-NEXT: -fxor-operator Enable .XOR. as a synonym of .NEQV.
 ! HELP-FC1-NEXT: -help  Display available options
+! HELP-FC1-NEXT: -init-only Only execute frontend initialization
 ! HELP-FC1-NEXT: -IAdd directory to the end of the list of include search paths
 ! HELP-FC1-NEXT: -module-dir   Put MODULE files in 
 ! HELP-FC1-NEXT: -nocpp Disable predefined and command line preprocessor macros
Index: flang/lib/FrontendTool/ExecuteCompilerInvocation.cpp
===
--- flang/lib/FrontendTool/ExecuteCompilerInvocation.cpp
+++ flang/lib/FrontendTool/ExecuteCompilerInvocation.cpp
@@ -73,6 +73,9 @@
   case GetSymbolsSources:
 return std::make_unique();
 break;
+  case InitOnly:
+return std::make_unique();
+break;
   default:
 break;
 // TODO:
Index: flang/lib/Frontend/FrontendActions.cpp
===
--- flang/lib/Frontend/FrontendActions.cpp
+++ flang/lib/Frontend/FrontendActions.cpp
@@ -447,3 +447,11 @@
   clang::DiagnosticsEngine::Error, "code-generation is not available yet");
   ci.diagnostics().Report(DiagID);
 }
+
+void InitOnlyAction::ExecuteAction() {
+  CompilerInstance &ci = this->instance();
+  unsigned DiagID =
+  ci.diagnostics().getCustomDiagID(clang::DiagnosticsEngine::Warning,
+  "Use `-init-only` for testing purposes only");
+  ci.diagnostics().Report(DiagID);
+}
Index: flang/lib/Frontend/CompilerInvocation.cpp
===
--- flang/lib/Frontend/CompilerInvocation.cpp
+++ flang/lib/Frontend/CompilerInvocation.cpp
@@ -162,9 +162,12 @@
 case clang::driver::options::OPT_fget_definition:
   opts.programAction_ = GetDefinition;
   break;
+case clang::driver::options::OPT_init_only:
+  opts.programAction_ = InitOnly;
+  break;
 
   // TODO:
-  // case calng::driver::options::OPT_emit_llvm:
+  // case clang::driver::options::OPT_emit_llvm:
   // case clang::driver::options::OPT_emit_llvm_only:
   // case clang::driver::options::OPT_emit_codegen_only:
   // case clang::driver::options::OPT_emit_module:
Index: flang/include/flang/Frontend/FrontendOptions.h
===
--- flang/include/flang/Frontend/FrontendOptions.h
+++ flang/include/flang/Frontend/FrontendOptions.h
@@ -71,7 +71,10 @@
   GetDefinition,
 
   /// Parse, run semantics and then dump symbol sources map
-  GetSymbolsSources
+  GetSymbolsSources,
+
+  /// Only execute frontend initialization
+  InitOnly
 
   /// TODO: RunPreprocessor, EmitLLVM, EmitLLVMOnly,
   /// EmitCodeGenOnly, EmitAssembly, (...)
Index: flang/include/flang/Frontend/FrontendActions.h
===
--- flang/include/flang/Frontend/FrontendActions.h
+++ flang/include/flang/Frontend/FrontendActions.h
@@ -38,6 +38,10 @@
   void ExecuteAction() override;
 };
 
+class InitOnlyAction : public FrontendAction {
+  void ExecuteAction() override;
+};
+
 //===--===//
 // Prescan Actions
 //===--===//
Index: clang/include/clang/Driver/Options.td
===
--- clang/include/clang/Driver/Options.td
+++ clang/include/clang/Driver/Options.td
@@ -5224,8 +5224,6 @@
   HelpText<

[PATCH] D106137: [flang][driver] Add support for Frontend Plugins

2021-08-10 Thread Stuart Ellis via Phabricator via cfe-commits 
stuartellis updated this revision to Diff 365411.
stuartellis marked an inline comment as done.
stuartellis added a comment.

Address review comments
Small changes due to rebase


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D106137/new/

https://reviews.llvm.org/D106137

Files:
  clang/include/clang/Driver/Options.td
  flang/CMakeLists.txt
  flang/examples/CMakeLists.txt
  flang/examples/HelloWorld/CMakeLists.txt
  flang/examples/HelloWorld/HelloWorldPlugin.cpp
  flang/include/flang/Frontend/FrontendActions.h
  flang/include/flang/Frontend/FrontendOptions.h
  flang/include/flang/Frontend/FrontendPluginRegistry.h
  flang/lib/Frontend/CompilerInvocation.cpp
  flang/lib/Frontend/FrontendAction.cpp
  flang/lib/Frontend/FrontendActions.cpp
  flang/lib/FrontendTool/ExecuteCompilerInvocation.cpp
  flang/test/CMakeLists.txt
  flang/test/Driver/driver-help.f90
  flang/test/Driver/plugin-example.f90
  flang/test/lit.cfg.py
  flang/test/lit.site.cfg.py.in
  flang/tools/flang-driver/CMakeLists.txt

Index: flang/tools/flang-driver/CMakeLists.txt
===
--- flang/tools/flang-driver/CMakeLists.txt
+++ flang/tools/flang-driver/CMakeLists.txt
@@ -27,4 +27,11 @@
   clangBasic
 )
 
+option(FLANG_PLUGIN_SUPPORT "Build Flang with plugin support." ON)
+
+# Enable support for plugins, which need access to symbols from flang-new
+if(FLANG_PLUGIN_SUPPORT)
+  export_executable_symbols_for_plugins(flang-new)
+endif()
+
 install(TARGETS flang-new DESTINATION bin)
Index: flang/test/lit.site.cfg.py.in
===
--- flang/test/lit.site.cfg.py.in
+++ flang/test/lit.site.cfg.py.in
@@ -3,6 +3,8 @@
 import sys
 
 config.llvm_tools_dir = "@LLVM_TOOLS_DIR@"
+config.llvm_shlib_dir = path(r"@SHLIBDIR@")
+config.llvm_plugin_ext = "@LLVM_PLUGIN_EXT@"
 config.lit_tools_dir = "@LLVM_LIT_TOOLS_DIR@"
 config.flang_obj_root = "@FLANG_BINARY_DIR@"
 config.flang_src_dir = "@FLANG_SOURCE_DIR@"
@@ -10,8 +12,10 @@
 config.flang_intrinsic_modules_dir = "@FLANG_INTRINSIC_MODULES_DIR@"
 config.flang_llvm_tools_dir = "@CMAKE_BINARY_DIR@/bin"
 config.flang_lib_dir = "@CMAKE_BINARY_DIR@/lib"
+config.flang_examples = @FLANG_BUILD_EXAMPLES@
 config.python_executable = "@PYTHON_EXECUTABLE@"
 config.flang_standalone_build = @FLANG_STANDALONE_BUILD@
+config.has_plugins = @LLVM_ENABLE_PLUGINS@
 config.cc = "@CMAKE_C_COMPILER@"
 
 # Support substitution of the tools_dir with user parameters. This is
@@ -19,6 +23,7 @@
 try:
 config.llvm_tools_dir = config.llvm_tools_dir % lit_config.params
 config.flang_tools_dir = config.flang_tools_dir % lit_config.params
+config.llvm_shlib_dir = config.llvm_shlib_dir % lit_config.params
 except KeyError:
 e = sys.exc_info()[1]
 key, = e.args
Index: flang/test/lit.cfg.py
===
--- flang/test/lit.cfg.py
+++ flang/test/lit.cfg.py
@@ -30,6 +30,8 @@
'.CUF', '.f18', '.F18', '.fir', '.f03', '.F03', '.f08', '.F08']
 
 config.substitutions.append(('%PATH%', config.environment['PATH']))
+config.substitutions.append(('%llvmshlibdir', config.llvm_shlib_dir))
+config.substitutions.append(('%pluginext', config.llvm_plugin_ext))
 
 llvm_config.use_default_substitutions()
 
@@ -42,6 +44,14 @@
 # config.
 config.available_features.add('new-flang-driver')
 
+# If the flang examples are built, add examples to the config
+if config.flang_examples:
+config.available_features.add('examples')
+
+# Plugins (loadable modules)
+if config.has_plugins:
+config.available_features.add('plugins')
+
 # test_source_root: The root path where tests are located.
 config.test_source_root = os.path.dirname(__file__)
 
Index: flang/test/Driver/plugin-example.f90
===
--- /dev/null
+++ flang/test/Driver/plugin-example.f90
@@ -0,0 +1,11 @@
+! Check that loading and running the Hello World plugin example results in the correct print statement
+! Also check that when a plugin name isn't found, the error diagnostic is correct
+! This requires that the examples are built (FLANG_BUILD_EXAMPLES=ON)
+
+! REQUIRES: new-flang-driver, plugins, examples, shell
+
+! RUN: %flang_fc1 -load %llvmshlibdir/flangHelloWorldPlugin%pluginext -plugin -hello-world %s 2>&1 | FileCheck %s
+! CHECK: Hello World from your new Flang plugin
+
+! RUN: not %flang_fc1 -load %llvmshlibdir/flangHelloWorldPlugin%pluginext -plugin -wrong-name %s 2>&1 | FileCheck %s --check-prefix=ERROR
+! ERROR: error: unable to find plugin '-wrong-name'
Index: flang/test/Driver/driver-help.f90
===
--- flang/test/Driver/driver-help.f90
+++ flang/test/Driver/driver-help.f90
@@ -123,11 +123,13 @@
 ! HELP-FC1-NEXT: -help  Display available options
 ! HELP-FC1-NEXT: -init-only Only execute frontend initial