diff options
Diffstat (limited to 'subx/050_write.subx')
| -rw-r--r-- | subx/050_write.subx | 24 |
1 files changed, 12 insertions, 12 deletions
diff --git a/subx/050_write.subx b/subx/050_write.subx index 1975f7a3..bb0f20e1 100644 --- a/subx/050_write.subx +++ b/subx/050_write.subx @@ -1,9 +1,9 @@ # _write: write to a file descriptor == code -# instruction effective address operand 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 +# 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: # syscall(exit, 0) -- can't test _write just yet @@ -12,34 +12,34 @@ cd/syscall 0x80/imm8 _write: # fd : int, s : (address array byte) -> <void> - # prolog + # . prolog 55/push-EBP 89/copy 3/mod/direct 5/rm32/EBP . . . 4/r32/ESP . . # copy ESP to EBP - # save registers + # . save registers 50/push-EAX 51/push-ECX 52/push-EDX 53/push-EBX # syscall(write, fd, (data) s+4, (size) *s) - # fd : EBX + # . fd : EBX 8b/copy 1/mod/*+disp8 4/rm32/sib 5/base/EBP 4/index/none . 3/r32/EBX 8/disp8 . # copy *(EBP+8) to EBX - # data : ECX = s+4 + # . data : ECX = s+4 8b/copy 1/mod/*+disp8 4/rm32/sib 5/base/EBP 4/index/none . 1/r32/ECX 0xc/disp8 . # copy *(EBP+12) to ECX 81 0/subop/add 3/mod/direct 1/rm32/ECX . . . . . 4/imm32 # add to ECX - # size : EDX = *s + # . size : EDX = *s 8b/copy 1/mod/*+disp8 4/rm32/sib 5/base/EBP 4/index/none . 2/r32/EDX 0xc/disp8 . # copy *(EBP+12) to EDX 8b/copy 0/mod/indirect 2/rm32/EDX . . . 2/r32/EDX . . # copy *EDX to EDX - # syscall + # . syscall b8/copy-to-EAX 4/imm32/write cd/syscall 0x80/imm8 - # restore registers + # . restore registers 5b/pop-to-EBX 5a/pop-to-EDX 59/pop-to-ECX 58/pop-to-EAX - # epilog + # . epilog 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 +# . . vim:nowrap:textwidth=0 |