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Re: Compare Elimination problems


Hello!

> While I'm here, in i386.md some of the flag setting operations specify a mode and some don't . Eg
>
> (define_expand "cmp<mode>_1"
>   [(set (reg:CC FLAGS_REG)
>     (compare:CC (match_operand:SWI48 0 "nonimmediate_operand")
>
>
> (define_insn "*add<mode>_3"
>   [(set (reg FLAGS_REG)
>     (compare

The mode of the mode-less FLAGS_REG is checked with ix86_match_ccmode
in the insn constraint. Several modes are compatible with required
mode, also depending on input operands.

Uros.


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