Chris Demetriou firstname.lastname@example.org writes:
>[ Added David Anderson (hopefully still 8-) @ SGI to the CC list,
>since he's been helpful with sorting out questions like this in the
>At Thu, 25 Jul 2002 15:26:19 +0000 (UTC), "H. J. Lu" wrote:
>> I'd like to fix binutils ASAP. Here is a patch.
>People using stock binutils have been using the current binutils MIPS
>arch values for a While now. They were in 2.11.1 and later binutils
>releases, as well.
>> > /* ELF header e_flags defines. MIPS architecture level. */
>> > #define EF_MIPS_ARCH_1 0x00000000 /* -mips1 code. */
>> > #define EF_MIPS_ARCH_2 0x10000000 /* -mips2 code. */
>> > #define EF_MIPS_ARCH_3 0x20000000 /* -mips3 code. */
>> > #define EF_MIPS_ARCH_4 0x30000000 /* -mips4 code. */
>> > #define EF_MIPS_ARCH_5 0x40000000 /* -mips5 code. */
>> > #define EF_MIPS_ARCH_32 0x60000000 /* MIPS32 code. */
>> > #define EF_MIPS_ARCH_64 0x70000000 /* MIPS64 code. */
>> > #define EF_MIPS_ARCH_32R2 0x80000000 /* MIPS32 code. */
>> > #define EF_MIPS_ARCH_64R2 0x90000000 /* MIPS64 code. */
>Why are 2 definitions of MIPS32 and MIPS64 needed?
>Certainly, if you do need different definitions, they need much better
>comments than that.
>> > The missing value 0x50000000, is because IRIX has defined a EF_MIPS_ARCH_6
>> > and Algorithmics has a E_MIPS_ARCH_ALGOR_32, which has this value.
The latest IRIX def (not yet released header fragment):
elf.h:#define EF_MIPS_ARCH 0xf0000000 /* mask: 4 bit field */
elf.h:#define EF_MIPS_ARCH_1 0x00000000 /* MIPS I ISA */
elf.h:#define EF_MIPS_ARCH_2 0x10000000 /* MIPS II ISA */
elf.h:#define EF_MIPS_ARCH_3 0x20000000 /* MIPS III ISA */
elf.h:#define EF_MIPS_ARCH_4 0x30000000 /* MIPS IV ISA */
elf.h:#define EF_MIPS_ARCH_5 0x40000000 /* MIPS V ISA */
elf.h:#define EF_MIPS_ARCH_6 0x50000000
elf.h:#define EF_MIPS_ARCH_32 0x50000000 /* MIPS32 ISA */
elf.h:#define EF_MIPS_ARCH_64 0x60000000 /* MIPS64 ISA */
EF_MIPS_ARCH_32 duplicates EF_MIPS_ARCH_6 for basically historical
reasons I think : we did not want some compile to fail for no good reason
if EF_MIPS_ARCH_6 was referred to.
We never have used EF_MIPS_ARCH_6 for anything.
The EF_MIPS_ARCH_64 0x60000000
we got from binutils(!) around Nov 2001, according to my
email records. Without much certainty it was the right value.
>It's unfortunate that MIPS is only at this late stage getting into the
>business of defining these fields.
>Has IRIX actually _used_ EF_MIPS_ARCH_6 for anything (shipped)? That
>i'm a bit concerned about, since interoperability with IRIX would be a
>good thing given that SGI has been setting the only ABI example to
>follow for MIPS.
No, IRIX never used EF_MIPS_ARCH_6 0x50000000 for anything
>Algorithmics may have done something different, but they have also
>been capable of contributing their binutils-related changes back to
>the binutils projects, yet they have not. Why muck things up for
>people who _have_, or who've been using the tools, on their account?
Nor have we shipped EF_MIPS_ARCH_32 or EF_MIPS_ARCH_64
(from the IRIX set above).
While I cannot speak for everyone here, I'm pretty sure that
we can follow what is eventually adopted, since the values in question
represent nothing shipped.
We added EF_MIPS_ARCH_5 0x40000000
and EF_MIPS_ARCH_6 0x50000000 to elf.h
long long ago.
I don't *think* we've shipped EF_MIPS_ARCH_5 0x40000000
either, but I could well be wrong on that, I forget
what was said/done on EF_MIPS_ARCH_5. If it matters
I could check (let me know).
I've added a couple key interested sgi folks (via bcc,
I don't know they want email addresses exposed) to this
response. So if I've made mistakes above such can
David B. Anderson email@example.com http://reality.sgiweb.org/davea