ex14.subx « apps - mu - Soul of a tiny new machine. More thorough tests → More comprehensible and rewrite-friendly software → More resilient society.

blob: 74dd3809e3e9f919138eae59b5f7dc488443311b (plain) (tree)

8f256f1f ^

1
2
3
4pre { line-height: 125%; }
td.linenos .normal { color: inherit; background-color: transparent; padding-left: 5px; padding-right: 5px; }
span.linenos { color: inherit; background-color: transparent; padding-left: 5px; padding-right: 5px; }
td.linenos .special { color: #000000; background-color: #ffffc0; padding-left: 5px; padding-right: 5px; }
span.linenos.special { color: #000000; background-color: #ffffc0; padding-left: 5px; padding-right: 5px; }
.highlight .hll { background-color: #ffffcc }
.highlight .c { color: #888888 } /* Comment */
.highlight .err { color: #a61717; background-color: #e3d2d2 } /* Error */
.highlight .k { color: #008800; font-weight: bold } /* Keyword */
.highlight .ch { color: #888888 } /* Comment.Hashbang */
.highlight .cm { color: #888888 } /* Comment.Multiline */
.highlight .cp { color: #cc0000; font-weight: bold } /* Comment.Preproc */
.highlight .cpf { color: #888888 } /* Comment.PreprocFile */
.highlight .c1# Multiply 2 numbers.
#
# To run:
#   $ ./bootstrap translate init.linux apps/ex14.subx -o apps/ex14
#   $ ./bootstrap run apps/ex14
# Expected result:
#   $ echo $?
#   6

== 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:
    b8/copy-to-eax  1/imm32
    b9/copy-to-ecx  2/imm32
    bb/copy-to-ebx  3/imm32

    69/multiply                     3/mod/direct    1/rm32/ecx    .           .             .           3/r32/ebx                   3/imm32           # ebx = ecx * 3

$exit:
    # exit(ebx)
    e8/call  syscall_exit/disp32

# . . vim:nowrap:textwidth=0