Question about getg_arm64.s on Arm64 server.

[eric-yq]

Hi , I am using this package on AWS Graviton4(Arm64, Neoverse-V2 and ARMv9 ISA) and Go 1.23，but sometimes it crashed.
After debugging, we found that problem may be in getg_arm64.s file.
Should I change code of getg_arm64.s to following ones?

TEXT ·getg(SB), NOSPLIT, $0-8
    MOVD    g, R8     
    MOVD    R8, ret+0(FP)
    RET

1. change $0-4 to $0-8
2. change MOVW to MOVD

Thanks for helping.

[huandu]

@eric-yq The getg for arm64 is totally wrong in Go1.23. I just check Go source code. It becomes MOVD R28, your_dst. The register storing G pointer has been changed.

BTW, It's not recommended to use this package any more due to incompatible with Go 1.17+.

[huandu]

If you're interested in the definitions of special registers, you can check out this link.

https://github.com/golang/go/blob/c57b0d6c7e54284c8967530153774dbc62190b00/src/cmd/compile/abi-internal.md?plain=1#L549