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|
== 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
# main:
e8/call run-tests/disp32 # 'run-tests' is a function created automatically by SubX. It calls all functions that start with 'test-'.
# syscall(exit, Num-test-failures)
8b/copy 0/mod/indirect 5/rm32/.disp32 . . 3/r32/EBX Num-test-failures/disp32 # copy *Num-test-failures to EBX
b8/copy-to-EAX 1/imm32/exit
cd/syscall 0x80/imm8
# extract the next run of characters that are different from a given 'delimiter'
# on eof return an empty interval
next-token: # in : (address stream), delimiter : byte, out : (address slice)
# . prolog
55/push-EBP
89/copy 3/mod/direct 5/rm32/EBP . . . 4/r32/ESP . . # copy ESP to EBP
# . save registers
50/push-EAX
51/push-ECX
56/push-ESI
57/push-EDI
# ESI = in
8b/copy 1/mod/*+disp8 5/rm32/EBP . . . 6/r32/ESI 8/disp8 . # copy *(EBP+8) to ESI
# EDI = out
8b/copy 1/mod/*+disp8 5/rm32/EBP . . . 7/r32/EDI 0x10/disp8 . # copy *(EBP+16) to EDI
# skip-chars-matching(in, delimiter)
# . . push args
ff 6/subop/push 1/mod/*+disp8 5/rm32/EBP . . . . 0xc/disp8 . # push *(EBP+12)
ff 6/subop/push 1/mod/*+disp8 5/rm32/EBP . . . . 8/disp8 . # push *(EBP+8)
# . . call
e8/call skip-chars-matching/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/ESP . . . . . 8/imm32 # add to ESP
# out->start = &in->data[in->read]
8b/copy 1/mod/*+disp8 6/rm32/ESI . . . 1/r32/ECX 4/disp8 . # copy *(ESI+4) to ECX
8d/copy-address 1/mod/*+disp8 4/rm32/sib 6/base/ESI 1/index/ECX . 0/r32/EAX 0xc/disp8 . # copy ESI+ECX+12 to EAX
89/copy 0/mod/indirect 7/rm32/EDI . . . 0/r32/EAX . . # copy EAX to *EDI
# skip-chars-not-matching(in, delimiter)
# . . push args
ff 6/subop/push 1/mod/*+disp8 5/rm32/EBP . . . . 0xc/disp8 . # push *(EBP+12)
ff 6/subop/push 1/mod/*+disp8 5/rm32/EBP . . . . 8/disp8 . # push *(EBP+8)
# . . call
e8/call skip-chars-not-matching/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/ESP . . . . . 8/imm32 # add to ESP
# out->end = &in->data[in->read]
8b/copy 1/mod/*+disp8 6/rm32/ESI . . . 1/r32/ECX 4/disp8 . # copy *(ESI+4) to ECX
8d/copy-address 1/mod/*+disp8 4/rm32/sib 6/base/ESI 1/index/ECX . 0/r32/EAX 0xc/disp8 . # copy ESI+ECX+12 to EAX
89/copy 1/mod/*+disp8 7/rm32/EDI . . . 0/r32/EAX 4/disp8 . # copy EAX to *(EDI+4)
# . restore registers
5f/pop-to-EDI
5e/pop-to-ESI
59/pop-to-ECX
58/pop-to-EAX
# . epilog
89/copy 3/mod/direct 4/rm32/ESP . . . 5/r32/EBP . . # copy EBP to ESP
5d/pop-to-EBP
c3/return
test-next-token:
# . prolog
55/push-EBP
89/copy 3/mod/direct 5/rm32/EBP . . . 4/r32/ESP . . # copy ESP to EBP
# setup
# . clear-stream(_test-stream)
# . . push args
68/push _test-stream/imm32
# . . call
e8/call clear-stream/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/ESP . . . . . 4/imm32 # add to ESP
# var slice/ECX = {0, 0}
68/push 0/imm32/end
68/push 0/imm32/start
89/copy 3/mod/direct 1/rm32/ECX . . . 4/r32/ESP . . # copy ESP to ECX
# write(_test-stream, " ab")
# . . push args
68/push " ab"/imm32
68/push _test-stream/imm32
# . . call
e8/call write/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/ESP . . . . . 8/imm32 # add to ESP
# next-token(_test-stream, 0x20/space, slice)
# . . push args
51/push-ECX
68/push 0x20/imm32
68/push _test-stream/imm32
# . . call
e8/call next-token/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/ESP . . . . . 0xc/imm32 # add to ESP
# check-ints-equal(slice->start - _test-stream->data, 2, msg)
# . check-ints-equal(slice->start - _test-stream, 14, msg)
# . . push args
68/push "F - test-next-token: start"/imm32
68/push 0xe/imm32
# . . push slice->start - _test-stream
8b/copy 0/mod/indirect 1/rm32/ECX . . . 0/r32/EAX . . # copy *ECX to EAX
81 5/subop/subtract 3/mod/direct 0/rm32/EAX . . . . . _test-stream/imm32 # subtract from EAX
50/push-EAX
# . . call
e8/call check-ints-equal/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/ESP . . . . . 0xc/imm32 # add to ESP
# check-ints-equal(slice->end - _test-stream->data, 4, msg)
# . check-ints-equal(slice->end - _test-stream, 16, msg)
# . . push args
68/push "F - test-next-token: end"/imm32
68/push 0x10/imm32
# . . push slice->end - _test-stream
8b/copy 1/mod/*+disp8 1/rm32/ECX . . . 0/r32/EAX 4/disp8 . # copy *(ECX+4) to EAX
81 5/subop/subtract 3/mod/direct 0/rm32/EAX . . . . . _test-stream/imm32 # subtract from EAX
50/push-EAX
# . . call
e8/call check-ints-equal/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/ESP . . . . . 0xc/imm32 # add to ESP
# . epilog
89/copy 3/mod/direct 4/rm32/ESP . . . 5/r32/EBP . . # copy EBP to ESP
5d/pop-to-EBP
c3/return
test-next-token-eof:
# . prolog
55/push-EBP
89/copy 3/mod/direct 5/rm32/EBP . . . 4/r32/ESP . . # copy ESP to EBP
# setup
# . clear-stream(_test-stream)
# . . push args
68/push _test-stream/imm32
# . . call
e8/call clear-stream/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/ESP . . . . . 4/imm32 # add to ESP
# var slice/ECX = {0, 0}
68/push 0/imm32/end
68/push 0/imm32/start
89/copy 3/mod/direct 1/rm32/ECX . . . 4/r32/ESP . . # copy ESP to ECX
# write nothing to _test-stream
# next-token(_test-stream, 0x20/space, slice)
# . . push args
51/push-ECX
68/push 0x20/imm32
68/push _test-stream/imm32
# . . call
e8/call next-token/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/ESP . . . . . 0xc/imm32 # add to ESP
# check-ints-equal(slice->end, slice->start, msg)
# . . push args
68/push "F - test-next-token-eof"/imm32
ff 6/subop/push 1/mod/*+disp8 1/rm32/ECX . . . . 4/disp8 . # push *(ECX+4)
ff 6/subop/push 0/mod/indirect 1/rm32/ECX . . . . . . # push *ECX
# . . call
e8/call check-ints-equal/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/ESP . . . . . 0xc/imm32 # add to ESP
# . epilog
89/copy 3/mod/direct 4/rm32/ESP . . . 5/r32/EBP . . # copy EBP to ESP
5d/pop-to-EBP
c3/return
skip-chars-matching: # in : (address stream), delimiter : byte
# . prolog
55/push-EBP
89/copy 3/mod/direct 5/rm32/EBP . . . 4/r32/ESP . . # copy ESP to EBP
# . save registers
50/push-EAX
51/push-ECX
52/push-EDX
56/push-ESI
# ESI = in
8b/copy 1/mod/*+disp8 5/rm32/EBP . . . 6/r32/ESI 8/disp8 . # copy *(EBP+8) to ESI
# ECX = in->read
8b/copy 1/mod/*+disp8 6/rm32/ESI . . . 1/r32/ECX 4/disp8 . # copy *(ESI+4) to ECX
# EBX = in->write
8b/copy 0/mod/indirect 6/rm32/ESI . . . 3/r32/EBX . . # copy *ESI to EBX
# EDX = delimiter
8b/copy 1/mod/*+disp8 5/rm32/EBP . . . 2/r32/EDX 0xc/disp8 . # copy *(EBP+12) to EDX
$skip-chars-matching:loop:
# if (in->read >= in->write) break
3b/compare 3/mod/direct 3/rm32/EBX . . . 1/r32/ECX . . # compare ECX with *EBX
7d/jump-if-greater-or-equal $skip-chars-matching:end/disp8
# EAX = in->data[in->read]
31/xor 3/mod/direct 0/rm32/EAX . . . 0/r32/EAX . . # clear EAX
8a/copy-byte 1/mod/*+disp8 4/rm32/sib 6/base/ESI 1/index/ECX . 0/r32/AL 0xc/disp8 . # copy byte at *(ESI+ECX+12) to AL
# if (EAX != delimiter) break
39/compare 3/mod/direct 0/rm32/EAX . . . 2/r32/EDX . . # compare EAX and EDX
75/jump-if-not-equal $skip-chars-matching:end/disp8
# ++in->read
41/inc-ECX
eb/jump $skip-chars-matching:loop/disp8
$skip-chars-matching:end:
# persist in->read
89/copy 1/mod/*+disp8 6/rm32/ESI . . . 1/r32/ECX 4/disp8 . # copy ECX to *(ESI+4)
# . restore registers
5e/pop-to-ESI
5a/pop-to-EDX
59/pop-to-ECX
58/pop-to-EAX
# . epilog
89/copy 3/mod/direct 4/rm32/ESP . . . 5/r32/EBP . . # copy EBP to ESP
5d/pop-to-EBP
c3/return
test-skip-chars-matching:
# setup
# . clear-stream(_test-stream)
# . . push args
68/push _test-stream/imm32
# . . call
e8/call clear-stream/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/ESP . . . . . 4/imm32 # add to ESP
# write(_test-stream, " ab")
# . . push args
68/push " ab"/imm32
68/push _test-stream/imm32
# . . call
e8/call write/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/ESP . . . . . 8/imm32 # add to ESP
# skip-chars-matching(_test-stream, 0x20/space)
# . . push args
68/push 0x20/imm32
68/push _test-stream/imm32
# . . call
e8/call skip-chars-matching/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/ESP . . . . . 8/imm32 # add to ESP
# check-ints-equal(_test-stream->read, 2, msg)
# . . push args
68/push "F - test-skip-chars-matching"/imm32
68/push 2/imm32
# . . push *_test-stream->read
b8/copy-to-EAX _test-stream/imm32
ff 6/subop/push 1/mod/*+disp8 0/rm32/EAX . . . . 4/disp8 . # push *(EAX+4)
# . . call
e8/call check-ints-equal/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/ESP . . . . . 0xc/imm32 # add to ESP
# end
c3/return
test-skip-chars-matching-none:
# setup
# . clear-stream(_test-stream)
# . . push args
68/push _test-stream/imm32
# . . call
e8/call clear-stream/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/ESP . . . . . 4/imm32 # add to ESP
# write(_test-stream, "ab")
# . . push args
68/push "ab"/imm32
68/push _test-stream/imm32
# . . call
e8/call write/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/ESP . . . . . 8/imm32 # add to ESP
# skip-chars-matching(_test-stream, 0x20/space)
# . . push args
68/push 0x20/imm32
68/push _test-stream/imm32
# . . call
e8/call skip-chars-matching/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/ESP . . . . . 8/imm32 # add to ESP
# check-ints-equal(_test-stream->read, 0, msg)
# . . push args
68/push "F - test-skip-chars-matching-none"/imm32
68/push 0/imm32
# . . push *_test-stream->read
b8/copy-to-EAX _test-stream/imm32
ff 6/subop/push 1/mod/*+disp8 0/rm32/EAX . . . . 4/disp8 . # push *(EAX+4)
# . . call
e8/call check-ints-equal/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/ESP . . . . . 0xc/imm32 # add to ESP
# end
c3/return
# minor fork of 'skip-chars-matching'
skip-chars-not-matching: # in : (address stream), delimiter : byte
# . prolog
55/push-EBP
89/copy 3/mod/direct 5/rm32/EBP . . . 4/r32/ESP . . # copy ESP to EBP
# . save registers
50/push-EAX
51/push-ECX
52/push-EDX
56/push-ESI
# ESI = in
8b/copy 1/mod/*+disp8 5/rm32/EBP . . . 6/r32/ESI 8/disp8 . # copy *(EBP+8) to ESI
# ECX = in->read
8b/copy 1/mod/*+disp8 6/rm32/ESI . . . 1/r32/ECX 4/disp8 . # copy *(ESI+4) to ECX
# EBX = in->write
8b/copy 0/mod/indirect 6/rm32/ESI . . . 3/r32/EBX . . # copy *ESI to EBX
# EDX = delimiter
8b/copy 1/mod/*+disp8 5/rm32/EBP . . . 2/r32/EDX 0xc/disp8 . # copy *(EBP+12) to EDX
$skip-chars-not-matching:loop:
# if (in->read >= in->write) break
3b/compare 3/mod/direct 3/rm32/EBX . . . 1/r32/ECX . . # compare ECX with *EBX
7d/jump-if-greater-or-equal $skip-chars-not-matching:end/disp8
# EAX = in->data[in->read]
31/xor 3/mod/direct 0/rm32/EAX . . . 0/r32/EAX . . # clear EAX
8a/copy-byte 1/mod/*+disp8 4/rm32/sib 6/base/ESI 1/index/ECX . 0/r32/AL 0xc/disp8 . # copy byte at *(ESI+ECX+12) to AL
# if (EAX == delimiter) break
39/compare 3/mod/direct 0/rm32/EAX . . . 2/r32/EDX . . # compare EAX and EDX
74/jump-if-equal $skip-chars-not-matching:end/disp8
# ++in->read
41/inc-ECX
eb/jump $skip-chars-not-matching:loop/disp8
$skip-chars-not-matching:end:
# persist in->read
89/copy 1/mod/*+disp8 6/rm32/ESI . . . 1/r32/ECX 4/disp8 . # copy ECX to *(ESI+4)
# . restore registers
5e/pop-to-ESI
5a/pop-to-EDX
59/pop-to-ECX
58/pop-to-EAX
# . epilog
89/copy 3/mod/direct 4/rm32/ESP . . . 5/r32/EBP . . # copy EBP to ESP
5d/pop-to-EBP
c3/return
test-skip-chars-not-matching:
# setup
# . clear-stream(_test-stream)
# . . push args
68/push _test-stream/imm32
# . . call
e8/call clear-stream/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/ESP . . . . . 4/imm32 # add to ESP
# write(_test-stream, "ab ")
# . . push args
68/push "ab "/imm32
68/push _test-stream/imm32
# . . call
e8/call write/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/ESP . . . . . 8/imm32 # add to ESP
# skip-chars-not-matching(_test-stream, 0x20/space)
# . . push args
68/push 0x20/imm32
68/push _test-stream/imm32
# . . call
e8/call skip-chars-not-matching/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/ESP . . . . . 8/imm32 # add to ESP
# check-ints-equal(_test-stream->read, 2, msg)
# . . push args
68/push "F - test-skip-chars-not-matching"/imm32
68/push 2/imm32
# . . push *_test-stream->read
b8/copy-to-EAX _test-stream/imm32
ff 6/subop/push 1/mod/*+disp8 0/rm32/EAX . . . . 4/disp8 . # push *(EAX+4)
# . . call
e8/call check-ints-equal/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/ESP . . . . . 0xc/imm32 # add to ESP
# end
c3/return
test-skip-chars-not-matching-none:
# setup
# . clear-stream(_test-stream)
# . . push args
68/push _test-stream/imm32
# . . call
e8/call clear-stream/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/ESP . . . . . 4/imm32 # add to ESP
# write(_test-stream, " ab")
# . . push args
68/push " ab"/imm32
68/push _test-stream/imm32
# . . call
e8/call write/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/ESP . . . . . 8/imm32 # add to ESP
# skip-chars-not-matching(_test-stream, 0x20/space)
# . . push args
68/push 0x20/imm32
68/push _test-stream/imm32
# . . call
e8/call skip-chars-not-matching/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/ESP . . . . . 8/imm32 # add to ESP
# check-ints-equal(_test-stream->read, 0, msg)
# . . push args
68/push "F - test-skip-chars-not-matching-none"/imm32
68/push 0/imm32
# . . push *_test-stream->read
b8/copy-to-EAX _test-stream/imm32
ff 6/subop/push 1/mod/*+disp8 0/rm32/EAX . . . . 4/disp8 . # push *(EAX+4)
# . . call
e8/call check-ints-equal/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/ESP . . . . . 0xc/imm32 # add to ESP
# end
c3/return
test-skip-chars-not-matching-all:
# setup
# . clear-stream(_test-stream)
# . . push args
68/push _test-stream/imm32
# . . call
e8/call clear-stream/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/ESP . . . . . 4/imm32 # add to ESP
# write(_test-stream, "ab")
# . . push args
68/push "ab"/imm32
68/push _test-stream/imm32
# . . call
e8/call write/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/ESP . . . . . 8/imm32 # add to ESP
# skip-chars-not-matching(_test-stream, 0x20/space)
# . . push args
68/push 0x20/imm32
68/push _test-stream/imm32
# . . call
e8/call skip-chars-not-matching/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/ESP . . . . . 8/imm32 # add to ESP
# check-ints-equal(_test-stream->read, 2, msg)
# . . push args
68/push "F - test-skip-chars-not-matching-all"/imm32
68/push 2/imm32
# . . push *_test-stream->read
b8/copy-to-EAX _test-stream/imm32
ff 6/subop/push 1/mod/*+disp8 0/rm32/EAX . . . . 4/disp8 . # push *(EAX+4)
# . . call
e8/call check-ints-equal/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/ESP . . . . . 0xc/imm32 # add to ESP
# end
c3/return
# . . vim:nowrap:textwidth=0
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