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Re: base + index register addressing
- To: nik at tiuk dot ti dot com
- Subject: Re: base + index register addressing
- From: Joern Rennecke <amylaar at cygnus dot co dot uk>
- Date: Tue, 21 Oct 1997 00:00:52 +0100 (BST)
- Cc: law at cygnus dot com, egcs at cygnus dot com, michaelh at ongaonga dot chch dot cri dot nz, meissner at cygnus dot com, gcc2 at cygnus dot com
> On some of TI's DSPs index/base are very important as well.
> This is almost the inverse of above case - sets of registers are vital !
> Here to use a register as an index its hard-register number has to be
> "related" to the hard register number of the base.
> Current GCC register allocation just cannot handle this, so I have
> "given up" (and just lurk here).
Why so you think gcc cannot handle this? Just describe the relatedness
of the registers with register classes, and enforce it in the REG_OK_STRICT
version of GO_IF_LEGITIMATE_ADDRESS .