Kevin D. Kissell wrote:
[snip]
> > `-mcpu=CPU TYPE'
> > Assume the defaults for the machine type CPU TYPE when scheduling
> > instructions. The choices for CPU TYPE are `r2000', `r3000',
> > `r3900', `r4000', `r4100', `r4300', `r4400', `r4600', `r4650',
> > `r5000', `r6000', `r8000', and `orion'. Additionally, the
> > `r2000', `r3000', `r4000', `r5000', and `r6000' can be abbreviated
> > as `r2k' (or `r2K'), `r3k', etc. While picking a specific CPU
> > TYPE will schedule things appropriately for that particular chip,
> > the compiler will not generate any code that does not meet level 1
> > of the MIPS ISA (instruction set architecture) without a `-mipsX'
> > or `-mabi' switch being used.
>
> In that case, the tools that I've been using are technically
> broken. Surprise surprise. Because -mcpu=4600 is
> most assuredly setting the ISA level, even if it doesn't
> override one explicitly set!
gas and gcc have different meanings for this option, gas uses the
cpu's default ISA (if none specified) while gcc uses MIPS I.
In current binutils/gcc CVS, there was -march and -mtune introduced
as a replacement for -mcpu and -m<cpu>, which were kept for backward
compatibility only.
[snip]
> > No MAD on R4600. Again it would be in contradiction with above document-
> > ation. Mad you get with:
>
> Right. Sorry. I got the 4600 and 4650 confused. I no longer
> understand why "4600" and not "4650" is the model for MIPS32.
At least for the CVS binutils gas it is Generic-MIPS32, not 4600.
Thiemo
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