RFR: 8365570: C2 fails assert(false) failed: Unexpected node in SuperWord truncation: CastII [v5]

[Tobias Hartmann]

On Tue, 6 Jan 2026 23:53:18 GMT, Jasmine Karthikeyan <jkarthikeyan at openjdk.org> wrote:

>> Hi all,
>> This is a quick patch for the assert failure in superword truncation with CastII. I've added a check for all constraint cast nodes, and attached a reduced version of the fuzzer test. Thanks!
>
> Jasmine Karthikeyan has updated the pull request incrementally with one additional commit since the last revision:
> 
>   Use Xcomp test run instead of Warmup(0)

I see timeouts with the test in various configurations, maybe the default timeout should be increased?


compiler.lib.ir_framework.driver.TestVMException: There were one or multiple errors. Please check stderr for more information.
	at compiler.lib.ir_framework.driver.TestVMProcess.throwTestVMException(TestVMProcess.java:251)
	at compiler.lib.ir_framework.driver.TestVMProcess.checkTestVMExitCode(TestVMProcess.java:232)
	at compiler.lib.ir_framework.driver.TestVMProcess.<init>(TestVMProcess.java:77)
	at compiler.lib.ir_framework.TestFramework.runTestVM(TestFramework.java:879)
	at compiler.lib.ir_framework.TestFramework.start(TestFramework.java:839)
	at compiler.lib.ir_framework.TestFramework.start(TestFramework.java:431)
	at compiler.lib.ir_framework.TestFramework.runWithFlags(TestFramework.java:257)
	at compiler.vectorization.TestSubwordTruncation.main(TestSubwordTruncation.java:509)
	at java.base/jdk.internal.reflect.DirectMethodHandleAccessor.invoke(DirectMethodHandleAccessor.java:104)
	at java.base/java.lang.reflect.Method.invoke(Method.java:565)
	at com.sun.javatest.regtest.agent.MainActionHelper$AgentVMRunnable.run(MainActionHelper.java:335)
	at java.base/java.lang.Thread.run(Thread.java:1516)

JavaTest Message: Test threw exception: compiler.lib.ir_framework.driver.TestVMException
JavaTest Message: shutting down test

result: Error. "driver" action timed out with a timeout of 480 seconds on agent 136; but completed after timeout - suppressed status: "Failed. `main' threw exception: compiler.lib.ir_framework.driver.TestVMException: There were one or multiple errors. Please check stderr for more information."


test result: Error. "driver" action timed out with a timeout of 480 seconds on agent 136; but completed after timeout - suppressed status: "Failed. `main' threw exception: compiler.lib.ir_framework.driver.TestVMException: There were one or multiple errors. Please check stderr for more information."

-------------

PR Comment: https://git.openjdk.org/jdk/pull/26827#issuecomment-3718183534