m68k build failure

Mark Phillips M.S.Phillips@nortel.co.uk
Thu Jun 5 10:49:00 GMT 1997

So it looks like the Motorola documentation is wrong again!!!

I was basing my comments on the "Motorola M68000 Family Programmer's
Reference Manual" dated 1992, downloaded from their web site. Page 4-193
lists "TST An" in the main table as mode 001 with the footnote that the
68020 68030 68040 and CPU32 only support it for word or long operation.
The other footnotes do mention the 68000 so I assumed.....

I, of course, believe what the real hardware does!!!

So I will update the patch I was going to submit to only add support for
the CPU32 (I'm using a 68360). The CPU32 (I believe the CPU32+ in the
68360 is a pure superset of the CPU32) manual I have does list TST.W An as
being legal.


Mark S. Phillips        ESN 742 2461
msp@nortel.co.uk        Tel. +44 1279 402461

On Wed, 4 Jun 1997, Ian Lance Taylor wrote:

> >BUT, I have discovered with some cpu settings (for example -m68020
> >-mnobitfield to cc1 in the CC1_SPEC) the compiler will generate tst
> >instructions on Address registers, this IS LEGAL, BUT the assembler
> >incorrectly rejects them if the cpu is < 68020.
> >TST.W or TST.L instructions on Address registers are actually supported on
> >all 68series CPUS.
> No, they aren't.  The 68000 does not support them.  If you don't
> believe me, check the Motorola documentation, or check an actual
> 68000.
> It's a compiler bug.
> Ian

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