[llvm] [LTO][Pipelines][Coro] Handle coroutines in LTO pipeline (PR #126168)

[Adrian Vogelsgesang via llvm-commits]

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@@ -1825,6 +1827,7 @@ PassBuilder::buildLTODefaultPipeline(OptimizationLevel Level,
     // in ICP.
     MPM.addPass(LowerTypeTestsPass(nullptr, nullptr,
                                    lowertypetests::DropTestKind::Assume));
+    MPM.addPass(CoroCleanupPass());
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vogelsgesang wrote:

am I reading the code correct as in: For a `-O0` build, we would only have the `CoroEarly` and the `CoroCleanup` pass? We only add the `CoroSplitPass` for `-O2`? Afaik, we do need the `CoroSplitPass` also for `O0` and `O1`

https://github.com/llvm/llvm-project/pull/126168