tcg/ppc: Add TCG_CT_CONST_CMP

Better constraint for tcg_out_cmp, based on the comparison.
We can't yet remove the fallback to load constants into a
scratch because of tcg_out_cmp2, but that path should not
be as frequent.

Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
3 files changed