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Re: What does this character mean in gcc's md file?


ZengNan <znxmu@yahoo.com.cn> writes:

> (define_insn ""
>   [(set (match_operand:CCFP 0 "register_operand" "=z")
>         (match_operator:SF 1 "signed_comparison_operator"
>          [(match_operand:SF 2 "register_operand" "f")
>           (match_operand:SF 3 "register_operand" "f")]))]
>   ""
>   "%C1f\\t%2,%3"
>   [(set_attr "type" "fp")
>    (set_attr "mode" "SF")])
> 
> This pattern outputs float compare instruction. "%C" in the output template is defined in dlx.c to
> be one of eq, ne, gt, lt, le and neq. DLX's assembly code for float compare has the format of "*f
> op1, op2", where * is to be substituted by eq, ne, gt, ....  I don't know the meaning of the
> numeric character "1" between "%C" and "f" in the output template.

It is the operand number which is used to determine what to print for
%C.  In this case the match_operator:SF, which is operand 1 in the
pattern (the 1 appears explicitly above).

Ian


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