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Re: accept 64-bit constant addresses in mips n32


Alexandre Oliva wrote:
> Even though n32 has a 32-bit address space, sometimes it is important
> to be able to reference uncached memory regions or so in n32,

(C)KSEG can be accessed, and 64-bit addressing is out of spec.

> and
> having the assembler drop the upper 32 bits of such addresses surely
> doesn't help.  This patch fixes the problem.  Approved by Eric
> Christopher.  I'm checking it in.

After thinking a bit about this, I'm still not sure if the 'fix' is ok.
n32 normally guarantees properly sign-extended 32-bit addresses, and
people may rely on it for pointer arithmethics (in broken code).

IMHO the assembler should complain about attempted 64-bit addressing
in order to catch compiler bugs.

For what actual usage scenario was this patch developed?


Thiemo


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