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chitselb / pettil

6502 Forth-83 dialect for the Commodore PET 2001
http://pettil.tumblr.com
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Slightly improved peq ? #86

Open barrym95838 opened 3 years ago

barrym95838 commented 3 years ago

If we're only concerned about the Z flag, we could shave two bytes and a few cycles here, right?:

peq
    lda stackh,x    ; [4]
    eor tos+1       ; [3]
    bne peq99       ; [2*]
    lda stackl,x    ; [4]
    eor tos         ; [3]
peq99
    rts             ; [6]       ; Z flag is (TOS = 2OS)