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Re: Unit-at-time related PRs

Jim Wilson <wilson at redhat dot com> writes:

> On some of the compact ISAs, e.g. SH, Thumb (ARM), MIPS16, the only
> addressing mode you have for getting to global data is pc-relative
> with an 8 bit offset.  The only way to make this work is to have per
> function constant tables which are placed inside the function if the
> function is larger than 256 bytes.

I say this not knowing much about these ISAs, but my understanding is
that they are not register-starved, and register-indirect addressing
is available.  Thus, what about an implementation similar to x86 PIC
mode, where a register is dedicated to hold the address of a shared
constant pool, and loaded at the beginning of each function?

zw
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