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# Print an error message followed by the text representation of a byte. Then exit.
== 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: # manual test
#? # . var ed/eax: exit-descriptor
#? 81 5/subop/subtract 3/mod/direct 4/rm32/esp . . . . . 8/imm32 # subtract from esp
#? 89/copy 3/mod/direct 0/rm32/eax . . . 4/r32/esp . . # copy esp to eax
#? # . configure ed to really exit()
#? # . . ed->target = 0
#? c7 0/subop/copy 0/mod/direct 0/rm32/eax . . . . . 0/imm32 # copy to *eax
#? # . error-byte(ed, Stdout, msg, 34)
#? 68/push 0x34/imm32
#? 68/push "abc"/imm32
#? 68/push Stderr/imm32
#? 50/push-eax
#? e8/call error-byte/disp32
#? # . 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
#? e8/call syscall_exit/disp32
# write(out, "Error: "+msg+": "+byte) then stop(ed, 1)
error-byte: # ed: (addr exit-descriptor), out: (addr buffered-file), msg: (addr array byte), n: byte
# . prologue
55/push-ebp
89/copy 3/mod/direct 5/rm32/ebp . . . 4/r32/esp . . # copy esp to ebp
# write-buffered(out, "Error: ")
# . . push args
68/push "Error: "/imm32
ff 6/subop/push 1/mod/*+disp8 5/rm32/ebp . . . . 0xc/disp8 . # push *(ebp+12)
# . . call
e8/call write-buffered/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 8/imm32 # add to esp
# write-buffered(out, msg)
# . . push args
ff 6/subop/push 1/mod/*+disp8 5/rm32/ebp . . . . 0x10/disp8 . # push *(ebp+16)
ff 6/subop/push 1/mod/*+disp8 5/rm32/ebp . . . . 0xc/disp8 . # push *(ebp+12)
# . . call
e8/call write-buffered/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 8/imm32 # add to esp
# write-buffered(out, ": ")
# . . push args
68/push ": "/imm32
ff 6/subop/push 1/mod/*+disp8 5/rm32/ebp . . . . 0xc/disp8 . # push *(ebp+12)
# . . call
e8/call write-buffered/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 8/imm32 # add to esp
# print-byte-buffered(out, byte)
# . . push args
ff 6/subop/push 1/mod/*+disp8 5/rm32/ebp . . . . 0x14/disp8 . # push *(ebp+20)
ff 6/subop/push 1/mod/*+disp8 5/rm32/ebp . . . . 0xc/disp8 . # push *(ebp+12)
# . . call
e8/call print-byte-buffered/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 8/imm32 # add to esp
# write-buffered(out, Newline)
# . . push args
68/push Newline/imm32
ff 6/subop/push 1/mod/*+disp8 5/rm32/ebp . . . . 0xc/disp8 . # push *(ebp+12)
# . . call
e8/call write-buffered/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 8/imm32 # add to esp
# flush(out)
# . . push args
ff 6/subop/push 1/mod/*+disp8 5/rm32/ebp . . . . 0xc/disp8 . # push *(ebp+12)
# . . call
e8/call flush/disp32
# . . discard args
81 0/subop/add 3/mod/direct 4/rm32/esp . . . . . 4/imm32 # add to esp
# stop(ed, 1)
# . . push args
68/push 1/imm32
ff 6/subop/push 1/mod/*+disp8 5/rm32/ebp . . . . 8/disp8 . # push *(ebp+8)
# . . call
e8/call stop/disp32
# should never get past this point
$error-byte:dead-end:
# . epilogue
89/copy 3/mod/direct 4/rm32/esp . . . 5/r32/ebp . . # copy ebp to esp
5d/pop-to-ebp
c3/return
# . . vim:nowrap:textwidth=0
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