RFR: 8370939: C2: SIGSEGV in SafePointNode::verify_input when processing MH call from Compile::process_late_inline_calls_no_inline()

[SendaoYan]

On Fri, 31 Oct 2025 16:39:07 GMT, Roland Westrelin <roland at openjdk.org> wrote:

> In test cases, `mh` is initially not constant so the method handle
> invoke can't be inlined. It is later found to be constant, so it can
> be turned into a direct call by
> `Compile::process_late_inline_calls_no_inline()`. In the meantime, the
> `CallNode` for the mh invoke is cloned (by loop switching). In the
> process, only a shallow copy of the `JVMState` for the call is
> made. The initial `CallNode` is the first to be processed by
> `Compile::process_late_inline_calls_no_inline()` and that causes that
> `CallNode` to become dead. The cloned `CallNode` is then
> processed. The `JVMState` for that one references the initial
> `CallNode` in its caller's `JVMState`. Because that node is dead, that
> causes a crash. The fix I propose is to make a deep copy of the
> `JVMState` when a `CallNode` is cloned, if a `CallGenerator` is
> assigned to the node.
> 
> The other failure I see with these tests is:
> 
> 
> #  Internal Error (/home/roland/jdk-jdk/src/hotspot/share/opto/compile.hpp:1091), pid=3319164, tid=3319186
> #  assert(_number_of_mh_late_inlines > 0) failed: _number_of_mh_late_inlines < 0 !
> 
> 
> because even though the `CallNode` is cloned, there's still only one
> late inline recorded. The fix here is to increment
> `_number_of_mh_late_inlines` when the node is cloned.
> 
> This was reported by the netty developers.

test/hotspot/jtreg/compiler/inlining/TestLateMHClonedCallNode.java line 28:

> 26:  * @bug 8370939
> 27:  * @summary C2: SIGSEGV in SafePointNode::verify_input when processing MH call from Compile::process_late_inline_calls_no_inline()
> 28:  * @run main/othervm -XX:-BackgroundCompilation -XX:CompileOnly=TestLateMHClonedCallNode::test1 -XX:CompileOnly=TestLateMHClonedCallNode::test2 TestLateMHClonedCallNode

Maybe we can split this as two lines

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PR Review Comment: https://git.openjdk.org/jdk/pull/28088#discussion_r2483106650