PoC for Flang Driver Plugins

1 files changed, 67 insertions, 0 deletions

diff --git a/flang/lib/FrontendTool/ExecuteCompilerInvocation.cpp b/flang/lib/FrontendTool/ExecuteCompilerInvocation.cpp
index 243e251..8ef0c93 100644
--- a/flang/lib/FrontendTool/ExecuteCompilerInvocation.cpp
+++ b/flang/lib/FrontendTool/ExecuteCompilerInvocation.cpp
@@ -13,11 +13,14 @@
 
 #include "flang/Frontend/CompilerInstance.h"
 #include "flang/Frontend/FrontendActions.h"
+#include "flang/Frontend/FrontendAction.h"
+#include "flang/Frontend/FrontendPluginRegistry.h"
 #include "clang/Driver/Options.h"
 #include "llvm/Option/OptTable.h"
 #include "llvm/Option/Option.h"
 #include "llvm/Support/BuryPointer.h"
 #include "llvm/Support/CommandLine.h"
+#include "llvm/Support/DynamicLibrary.h"
 
 namespace Fortran::frontend {
 
@@ -79,6 +82,22 @@ static std::unique_ptr<FrontendAction> CreateFrontendBaseAction(
   case InitOnly:
     return std::make_unique<InitOnlyAction>();
     break;
+  case PluginAction: {
+    llvm::outs() << "---------- (case: PluginAction) --------\n";
+    llvm::outs() << "   Plugin Action: " << ci.frontendOpts().ActionName << "\n";
+    for (const FrontendPluginRegistry::entry &plugin : FrontendPluginRegistry::entries()) {
+      llvm::outs() << "     " << plugin.getName() << "\t-- " << plugin.getDesc() << "\n";
+      if (plugin.getName() == ci.frontendOpts().ActionName) {
+        llvm::outs() << "We have found the plugin name!! :-)\n";
+        std::unique_ptr<PluginParseTreeAction> P(plugin.instantiate());
+        return std::move(P);
+      }
+    }
+
+    unsigned diagID = ci.diagnostics().getCustomDiagID(clang::DiagnosticsEngine::Error, "unable to find plugin '%0'");
+    ci.diagnostics().Report(diagID) << ci.frontendOpts().ActionName;
+    return nullptr;
+  }
   default:
     break;
     // TODO:
@@ -92,6 +111,26 @@ static std::unique_ptr<FrontendAction> CreateFrontendBaseAction(
   return 0;
 }
 
+/// <<< TEMP Plugin Example
+
+class HelloWorldFlangPlugin : public PluginParseTreeAction
+{
+  protected:
+    void ExecuteAction() override {
+      llvm::outs() << "Hello World from your new plugin (Hello World)\n";
+    }
+};
+
+class HelloTwoFlangPlugin : public PluginParseTreeAction
+{
+  protected:
+    void ExecuteAction() override {
+      llvm::outs() << "Hello World from your new plugin (Hello Two)\n";
+    }
+};
+
+/// <<<<< TEMP Plugin Example
+
 std::unique_ptr<FrontendAction> CreateFrontendAction(CompilerInstance &ci) {
   // Create the underlying action.
   std::unique_ptr<FrontendAction> act = CreateFrontendBaseAction(ci);
@@ -100,6 +139,7 @@ std::unique_ptr<FrontendAction> CreateFrontendAction(CompilerInstance &ci) {
 
   return act;
 }
+
 bool ExecuteCompilerInvocation(CompilerInstance *flang) {
   // Honor -help.
   if (flang->frontendOpts().showHelp_) {
@@ -117,6 +157,33 @@ bool ExecuteCompilerInvocation(CompilerInstance *flang) {
     return true;
   }
 
+  llvm::outs() << "------ (ExecuteCompilerInvocation) -----\n";
+
+  // Load any requested plugins.
+  for (const std::string &Path : flang->frontendOpts().plugins) {
+    llvm::outs() << "   Load :: Path >> " << Path << "\n";
+    std::string Error;
+    if (llvm::sys::DynamicLibrary::LoadLibraryPermanently(Path.c_str(), &Error)) {
+      unsigned diagID = flang->diagnostics().getCustomDiagID(clang::DiagnosticsEngine::Error, "unable to load plugin '%0': '%1'");
+      flang->diagnostics().Report(diagID) << Path << Error;
+    }
+  }
+
+  llvm::outs() << "    Plugin Registry List >>\n";
+  for (const FrontendPluginRegistry::entry &plugin : FrontendPluginRegistry::entries()) {
+    llvm::outs() << plugin.getName() << " -- " << plugin.getDesc() << "\n";
+  }
+  llvm::outs() << "    << Plugin Registry List\n";
+
+  static FrontendPluginRegistry::Add<HelloWorldFlangPlugin> X("-hello-wor", "simple Plugin example");
+  static FrontendPluginRegistry::Add<HelloTwoFlangPlugin> Y("hellotwo", "another print plugin example");
+
+  llvm::outs() << "----- (\\ExecuteCompilerInvocation) -----\n";
+
+  // If there were errors in processing arguments, don't do anything else.
+  if (flang->diagnostics().hasErrorOccurred())
+    return false;
+
   // Create and execute the frontend action.
   std::unique_ptr<FrontendAction> act(CreateFrontendAction(*flang));
   if (!act)