RFR: JDK-8330795 : C2: assert((uint)type <= T_CONFLICT && _zero_type[type] != nullptr) failed: bad type with -XX:-UseCompressedClassPointers

[Vladimir Kozlov]

On Wed, 8 May 2024 23:44:26 GMT, Cesar Soares Lucas <cslucas at openjdk.org> wrote:

> The `assert((uint)type <= T_CONFLICT && _zero_type[type] != nullptr) failed: bad type` failure was caused by the fact that we didn't have a "zero value" for the type T_METADATA. The RAM patch uses that data when it creates a Phi node merging Klass loads and UseCompressedClassPointers is disabled.
> 
> Tested with JTREG tier1-4 on Linux x86_64 & ARM64.

New test failed in GHA with 32-bit VM because:

Unrecognized VM option 'UseCompressedClassPointers'

You can add `-XX:+IgnoreUnrecognizedVMOptions` to run test on all platforms.

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PR Comment: https://git.openjdk.org/jdk/pull/19148#issuecomment-2101739736