Document psABI changes for Zcmt

[abukharmeh]

For the spec ratification, we need to document the following 3 items in psABI spec

1. Document the section name for the table. (e.g. .riscv.tbljalvec)
2. Document the symbol name of the section (e.g. __tbljalvec_base$)
3. Document how the linker optimizes (or relaxes) the program by zcmt.

Item 2 and 3 could be documented in a similar fashion to the Global-pointer Relaxation while item 1 needs to be documented in special-section chapter of the document

Thank you @kito-cheng for very helpful pointers

[abukharmeh]

@linsinan1995 @Xinlong-Wu Could you please have a go at documenting what is there or what we think is needed and create a PR to the psABI repo If someone else think they are able to do this documentation work, it would be really helpful

[abukharmeh]

This presentation gives details about the relaxation process in GCC, though I am not sure that's the ideal way to do it ! https://docs.google.com/presentation/d/1ilfCIc9Bv4Ryl2Uyl3uwYtANlh9GSIroQC8Z-VIfUPk/edit#slide=id.g10c480b750a_0_274

[linsinan1995]

I can help document the detail, but I would suggest we first decide and document the section and symbol name in ZC spec.

I am personally fine with your examples (.riscv.tbljalvec and __tbljalvec_base).

[Xinlong-Wu]

sure, I'm glad I could be of help

[abukharmeh]

Initial PR was created by @linsinan1995 thank you very much @Xinlong-Wu Please review it and check if there is anything that need to be added !

[tariqkurd-repo]

is this confirmed? Should I add

Document the section name for the table. (e.g. .riscv.tbljalvec) Document the symbol name of the section (e.g. __tbljalvec_base$)

to the spec?

[abukharmeh]

I think we can close this one now, do we need to document section name and symbol name in Zc* document, or psABI documentation would suffice ?