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Re: Help math RTL patterns...

On 01/17/2017 03:41 PM, Steve Silva wrote:

Hi Nathan,

Thanks for your advice.  I retooled the addhi3 sequence to look like this:



The md.texi file seems to have exactly the example you need:

 Here for example, is how the 68000 halfword-add
instruction is defined:

@smallexample
(define_insn "addhi3"
  [(set (match_operand:HI 0 "general_operand" "=m,r")
     (plus:HI (match_operand:HI 1 "general_operand" "%0,0")
              (match_operand:HI 2 "general_operand" "di,g")))]
  @dots{})

no need for an expander and 2 insn patterns.


--
Nathan Sidwell
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