[llvm-branch-commits] [clang] [llvm] [RFC][LLVM][Clang] Add LLVM plugin hook for back-ends (PR #170846)

[Alexis Engelke via llvm-branch-commits]

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@@ -1017,16 +1018,9 @@ void EmitAssemblyHelper::RunOptimizationPipeline(
     }
 #endif
   }
-  // Attempt to load pass plugins and register their callbacks with PB.
-  for (auto &PluginFN : CodeGenOpts.PassPlugins) {
-    auto PassPlugin = PassPlugin::Load(PluginFN);
-    if (PassPlugin) {
-      PassPlugin->registerPassBuilderCallbacks(PB);
-    } else {
-      Diags.Report(diag::err_fe_unable_to_load_plugin)
-          << PluginFN << toString(PassPlugin.takeError());
-    }
-  }
+  // Register plugin callbacks with PB.
+  for (auto &Plugin : Plugins)
+    Plugin.registerPassBuilderCallbacks(PB);
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aengelke wrote:

*Need* no, they continue to work just fine.

- LTO: yes, might be good to have at some point in the future.
- Flang: likewise.
- clang-linker-wrapper: if there's interest, this can be added. While it currently seems to load plugins, it doesn't seem to call any methods on them.
- MLIR ModuleToObject::translateToISA also only seems to be used for GPUs and MLIR doesn't do anything related to plugins right now.

opt doesn't call and lld doesn't directly call back-ends.

https://github.com/llvm/llvm-project/pull/170846