Define GOT before use

[kito-cheng]

Review comment come from @anderslindgren-iar and Anders Berg(IAR) https://lists.riscv.org/g/tech-toolchain-runtime/message/344

global offset table (GOT)

Anders: Where is the specification for GOT (how can one find it)?

    # Load value from a local symbol 
0:  auipc a0, %pcrel_hi(symbol)
    lw    a0, %pcrel_lo(0b)(a0)
    # Store value to a local symbol 
1:  auipc a0, %pcrel_hi(symbol)
    sw    a1, %pcrel_lo(1b)(a0)
    # Calculate address of a local symbol 
2:  auipc a0, %pcrel_hi(symbol)
    addi  a0, a0, %pcrel_lo(2b)
    # Calculate address of non-local symbol 
3:  auipc  a0, %got_pcrel_hi(symbol)
    l[w|d] a0, a0, %pcrel_lo(3b)

Anders: The example is pointless if one cannot find the specification for GOT.
Should it not be an additional case of how to read a non-local symbol?

[jrtc27]

https://github.com/riscv-non-isa/riscv-elf-psabi-doc/blob/master/riscv-elf.adoc#global-offset-table

[jrtc27]

Should it not be an additional case of how to read a non-local symbol?

No, because there is no special sequence. The load/store cases for local symbols are only shown because you can fold the addi for the address calculation into the load or store immediate offset, but you cannot fold a load into a load or store.

[kito-cheng]

As @jrtc27 mention, we've defined later, but I think adding an explicitly forward reference could be better, see #277