On Mon, 31 Oct 2011, Paulo J. Matos wrote: > On 31/10/11 05:36, Hans-Peter Nilsson wrote: > > BTW, I > > don't think it helps that someone decided the canonical form of > > a parallel that includes a CC-setter must have the CC-setting > > *first* (contrasting with the position of clobbers)... > > How did you reach this conclusion?
Not obvious or maybe I was unclear as to what I alluded? In the below insn-bodies, "sub" is the insn that sets cc0 as a side-effect. Supposed canonical form : (parallel [(set cc_reg) (compare ...)) (set destreg) (sub ...))]) and: (parallel [(set destreg) (sub ...)) (clobber cc_reg)]) But IMHO it'd be easier (for most values of "easier") to combine both patterns with that non-existing mechanism (and no, I don't count match_parallel) if we instead canonicalized on the CC_REG set being the same as the clobber position: (parallel [(set destreg) (sub ...)) (set cc_reg) (compare ...))]) with: (parallel [(set destreg) (sub ...)) (clobber cc_reg)]) brgds, H-P
