[llvm] [PassBuilder] Add callback invoking to PassBuilder string API (PR #157153)

[Min-Yih Hsu via llvm-commits]

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@@ -133,6 +133,42 @@ PB.registerPipelineParsingCallback([=](StringRef Name, LoopPassManager &PM,
   return false;
 });
 
+PB.registerPipelineParsingCallback([=](StringRef Name, ModulePassManager &PM,
+                                       ArrayRef<PassBuilder::PipelineElement>) {
+#define MODULE_CALLBACK(NAME, INVOKE) if (Name == NAME) { PB.INVOKE(PM, OptimizationLevel::O2); return true; }
+#include GET_PASS_REGISTRY
+#undef MODULE_CALLBACK
+#define MODULE_LTO_CALLBACK(NAME, INVOKE) if (Name == NAME) { PB.INVOKE(PM, OptimizationLevel::O2, ThinOrFullLTOPhase::None); return true; }
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mshockwave wrote:

is there any particular reason you lock it on `O2`? could we parameterize it with something like "VectorizerStartCallbacks<O3>"?

https://github.com/llvm/llvm-project/pull/157153