8371146: C2 SuperWord: VTransform::add_speculative_check uses pre_init that is pinned after Auto_Vectorization_Check, leading to bad graph

[eme64]

TODO

make sure failures are logged more clearly, under SW_REJECTIONS

During SuperWord, we want to insert the aliasing runtime check above 687 ParsePredicate which is annotated with #Auto_Vectorization_Check. For this, we require the pre_init value: 1244 AddI. Sadly, this value is pinned lower down.

So when we insert the aliasing runtime check, we create a bad (circular) graph:

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Issue

• JDK-8371146: C2 SuperWord: VTransform::add_speculative_check uses pre_init that is pinned after Auto_Vectorization_Check, leading to bad graph (Bug - P3)

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