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Annotation of researchv9/libc/sun/is68020.s, revision 1.1

1.1     ! root        1: |
        !             2: | @(#)is68020.s        1.1 (Sun) 2/3/86
        !             3: | is68020():
        !             4: |      returns 1 if running on 68020, 0 if running on 68000 or 68010
        !             5: |      The trick is that the old processors ignore scaled indexing
        !             6: |
        !             7:        .globl  _is68020
        !             8: _is68020:
        !             9:        moveq   #1,d0
        !            10: |      lea     a6@(0,d0:l:4),a1        | scale an index of 1 by a factor of 4
        !            11:        .long   0x43f60c00              | this atrocity is to fool the assembler
        !            12:        lea     a6@(4),a0               | should get same answer by adding 4
        !            13:        cmpl    a0,a1                   | if answers are same, we're on 68020
        !            14:        beq     1f
        !            15:        moveq   #0,d0                   | otherwise 68000 or 68010
        !            16: 1:
        !            17:        rts

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