8270995: [lworld] G1BarrierSetC2::step_over_gc_barrier asserts with "bad barrier shape"

[TobiHartmann]

The G1BarrierSetC2::step_over_gc_barrier code gets confused by a MemBarCPUOrder, assuming it belongs to a GC barrier. However, it comes from a MemBarStoreStore added by InlineTypeBaseNode::buffer that is then transformed to a MemBarCPUOrder by Escape Analysis because the allocation is non-escaping (ConnectionGraph::optimize_ideal_graph). I don't think we need a MemBarCPUOrder for inline type buffer allocations, EA should simply remove it.

I've filed JDK-8271280 to re-visit the barrier code.

Best regards,
Tobias

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• JDK-8270995: [lworld] G1BarrierSetC2::step_over_gc_barrier asserts with "bad barrier shape"

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8270995: [lworld] G1BarrierSetC2::step_over_gc_barrier asserts with "bad barrier shape"

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• 01: Full - Incremental (676b45a1)
• 00: Full (c8c1feda)

[TobiHartmann]

/integrate

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Going to push as commit 6160238.

[openjdk]

@TobiHartmann Pushed as commit 6160238.

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