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Re: Fix SPEC2000 GCC misscopilation and SIMD support
On Thu, Dec 12, 2002 at 08:54:07PM +0100, Jan Hubicka wrote:
> + /* Return a class of registers that cannot change FROM mode to TO mode.
> +
> + x87 registers can't do subreg as all values are reformated to extended
> + precision. XMM registers does not support with nonzero offsets equal
> + to 4, 8 and 12 otherwise valid for integer registers. Since we can't
> + determine these, prohibit all nonparadoxical subregs changing size. */
> +
> + #define CANNOT_CHANGE_MODE_CLASS(FROM, TO) \
> + (GET_MODE_SIZE (TO) < GET_MODE_SIZE (FROM) \
> + ? FLOAT_SSE_REGS \
> + : GET_MODE_SIZE (FROM) != GET_MODE_SIZE (TO) \
> + ? FLOAT_REGS : NO_REGS)
Don't MMX registers have the same problem?
r~