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Re: [rfc] For mips, sign-extended ecoff offsets
Date: Mon, 19 Jun 2000 20:07:59 -0700
From: Geoff Keating <geoffk@cygnus.com>
> From: Ulf Carlsson <ulfc@calypso.engr.sgi.com>
> Date: Mon, 19 Jun 2000 18:45:44 -0700 (PDT)
> On a 64-bit MIPS processor 32-bit addresses are of course sign
> extended, but this shouldn't concern the 32-bit BFD backend for MIPS
> in any way. Whether we sign extend the addresses or not shouldn't
> make any difference except in our internal representation of the
> bfd_vma. I may be wrong though!
The 64-bit MIPS machines often use the 32-bit ELF format, typically
because they have 32-bit memory addresses (I forget whether trying to
access 0x0000000087654321 gives you 0xffffffff87654321 or a trap).
I think the real reason this happens is historical--because we didn't
have a 64-bit MIPS format when we started supporting 64-bit MIPS
chips. I don't think there is any particularly legitimate reason to
use a 32-bit format for a 64-bit chip.
Ian