apps/ex10.subx


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3# String comparison: return 1 iff the two args passed in at the commandline are equal.
#
# To run:
#   $ ./bootstrap translate init.linux apps/ex10.subx -o apps/ex10
#   $ ./bootstrap run apps/ex10 abc abd
# Expected result:
#   $ echo $?
#   0  # false

== code
#   instruction                     effective address                                                   register    displacement    immediate
# . op          subop               mod             rm32          base        index         scale       r32
# . 1-3 bytes   3 bits              2 bits          3 bits        3 bits      3 bits        2 bits      2 bits      0/1/2/4 bytes   0/1/2/4 bytes

Entry:  # return argv-equal(argv[1], argv[2])
#       At the start of a SubX program:
#         argc: *esp
#         argv[0]: *(esp+4)
#         argv[1]: *(esp+8)
#         ...
    # . prologue
    89/copy