MVME5500 broken with gcc-4.0.2
Joel Sherrill <joel@OARcorp.com>
joel.sherrill at OARcorp.com
Tue Nov 1 14:25:12 UTC 2005
Till Straumann wrote:
> rtems/gcc (implicitely) uses -maltivec on all 74xx CPUS and
> the MVME5500 calls for -mcpu=7450.
> Unfortunately, with -maltivec, gcc uses vector registers for
> some optimizations.
What are those optimizations? Are they integer or floating point
The answer determines the proper thing for RTEMS to do.
> --> until proper altivec support is implemented in RTEMS random
> *data corruption* must be expected.
I can't tell from the gcc code when Altivec registers might get used
so my first guess would be that we would need _CPU_Context_Switch to
switch the Altivec registers and the contexts to include Altivec registers.
> make/custom/mvme5500: use -mcpu=750
> -- Till
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