arm64: fix slots with offset >32k

When slots are used with a large offset,
the emitter generates invalid assembly
code. That is caught later on by the
assembler, but it prevents compilation
of programs with large stack frames.

When a slot offset is too large to be
expressed as a constant offset to x29
(the frame pointer), emitins() inserts
a late Oaddr instruction to x16 and
replaces the large slot reference with
x16.

This change also gave me the opportunity
to refactor the save/restore logic for
callee-save registers.

This fixes the following Hare issue:
https://todo.sr.ht/~sircmpwn/hare/387

0 files changed, 0 insertions, 0 deletions