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Annotation of researchv9/libc/sun/is68020.s, revision 1.1.1.1

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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