From 8b0e960dbb2823b48f41c64bd6b1d4f5a6060b33 Mon Sep 17 00:00:00 2001 From: Kartik Agaram Date: Tue, 30 Oct 2018 23:03:36 -0700 Subject: 4741 Extract a helper that we'll need for 'read'. --- subx/055trace.subx | 62 ++++++++++++++++++++++++++++++++++++++++-------------- 1 file changed, 46 insertions(+), 16 deletions(-) (limited to 'subx/055trace.subx') diff --git a/subx/055trace.subx b/subx/055trace.subx index 37497aed..dd187c75 100644 --- a/subx/055trace.subx +++ b/subx/055trace.subx @@ -276,6 +276,40 @@ test-trace-empty-line: # 3-argument variant of _append _append-3: # out : address, outend : address, s : (array byte) -> num_bytes_appended/EAX + # prolog + 55/push-EBP + 89/copy 3/mod/direct 5/rm32/EBP . . . 4/r32/ESP . . # copy ESP to EBP + # save registers + 51/push-ECX + # _append-4(out, outend, &s.data[0], &s.data[s.length]) -> num_bytes_appended/EAX + # push &s.data[s.length] + # EAX = s + 8b/copy 1/mod/*+disp8 4/rm32/sib 5/base/EBP 4/index/none 0/r32/EAX 0x10/disp8 . # copy *(EBP+16) to EAX + # ECX = s.length + 8b/copy 0/mod/indirect 0/rm32/EAX . . . 1/r32/ECX . . # copy *EAX to ECX + # ECX = &s.data[s.length] + 8d/copy-address 1/mod/*+disp8 4/rm32/sib 0/base/EAX 1/index/ECX . 1/r32/ECX 4/disp8 . # copy EAX+ECX+4 to ECX + 51/push-ECX + # push &s.data[0] + 8d/copy-address 1/mod/*+disp8 0/rm32/EAX . . . 1/r32/ECX 4/disp8 . # copy EAX+4 to ECX + 51/push-ECX + # push outend + ff 6/subop/push 1/mod/*+disp8 4/rm32/sib 5/base/EBP 4/index/none . . 0xc/disp8 . # push *(EBP+12) + # push out + ff 6/subop/push 1/mod/*+disp8 4/rm32/sib 5/base/EBP 4/index/none . . 0x8/disp8 . # push *(EBP+8) + # call + e8/call _append-4/disp32 + # discard args + 81 0/subop/add 3/mod/direct 4/rm32/ESP . . . . . 0x10/imm32 # add to ESP + # restore registers + 59/pop-to-ECX + # epilog + 89/copy 3/mod/direct 4/rm32/ESP . . . 5/r32/EBP . . # copy EBP to ESP + 5d/pop-to-EBP + c3/return + +# 4-argument variant of _append +_append-4: # out : address, outend : address, in : address, inend : address -> num_bytes_appended/EAX # prolog 55/push-EBP 89/copy 3/mod/direct 5/rm32/EBP . . . 4/r32/ESP . . # copy ESP to EBP @@ -288,24 +322,20 @@ _append-3: # out : address, outend : address, s : (array byte) -> num_bytes_app # EAX/num_bytes_appended = 0 b8/copy-to-EAX 0/imm32 # EDI = out - 8b/copy 1/mod/*+disp8 4/rm32/sib 5/base/EBP 4/index/none 7/r32/EDI 0x8/disp8 . # copy *(EBP+8) to EDI + 8b/copy 1/mod/*+disp8 4/rm32/sib 5/base/EBP 4/index/none . 7/r32/EDI 0x8/disp8 . # copy *(EBP+8) to EDI # EDX = outend - 8b/copy 1/mod/*+disp8 4/rm32/sib 5/base/EBP 4/index/none 2/r32/EDX 0xc/disp8 . # copy *(EBP+12) to EDX - # ESI = s - 8b/copy 1/mod/*+disp8 4/rm32/sib 5/base/EBP 4/index/none 6/r32/ESI 0x10/disp8 . # copy *(EBP+16) to ESI - # ECX = s.length - 8b/copy 0/mod/indirect 6/rm32/ESI . . . 1/r32/ECX . . # copy *ESI to ECX - # ECX/srcend = &s.data[s.length] - 8d/copy-address 1/mod/*+disp8 4/rm32/sib 6/base/ESI 1/index/ECX . 1/r32/ECX 4/disp8 . # copy ESI+ECX+4 to ECX - # ESI/src = &s.data[0] - 81 0/subop/add 3/mod/direct 6/rm32/ESI . . . . . 4/imm32 # add to ESI -$_append-3:loop: + 8b/copy 1/mod/*+disp8 4/rm32/sib 5/base/EBP 4/index/none . 2/r32/EDX 0xc/disp8 . # copy *(EBP+12) to EDX + # ESI = in + 8b/copy 1/mod/*+disp8 4/rm32/sib 5/base/EBP 4/index/none . 6/r32/ESI 0x10/disp8 . # copy *(EBP+16) to ESI + # ECX = inend + 8b/copy 1/mod/*+disp8 4/rm32/sib 5/base/EBP 4/index/none . 1/r32/ECX 0x14/disp8 . # copy *(EBP+20) to ECX +$_append-4:loop: # if ESI/src >= ECX/srcend break 39/compare 3/mod/direct 6/rm32/ESI . . . 1/r32/ECX . . # compare ESI with ECX - 7d/jump-if-greater-or-equal $_append-3:end/disp8 - # if EDI/out >= EDX/outend break (for now silently ignore filled up trace buffer) + 7d/jump-if-greater-or-equal $_append-4:end/disp8 + # if EDI/out >= EDX/outend break (for now silently ignore filled up buffer) 39/compare 3/mod/direct 7/rm32/EDI . . . 2/r32/EDX . . # compare EDI with EDX - 7d/jump-if-greater-or-equal $_append-3:end/disp8 + 7d/jump-if-greater-or-equal $_append-4:end/disp8 # copy one byte from ESI/src to EDI/out 8a/copy-byte 0/mod/indirect 6/rm32/ESI . . . 3/r32/BL . . # copy byte at *ESI to BL 88/copy-byte 0/mod/indirect 7/rm32/EDI . . . 3/r32/BL . . # copy byte at BL to *EDI @@ -313,8 +343,8 @@ $_append-3:loop: 40/increment-EAX 46/increment-ESI 47/increment-EDI - eb/jump $_append-3:loop/disp8 -$_append-3:end: + eb/jump $_append-4:loop/disp8 +$_append-4:end: # restore registers 5f/pop-to-EDI 5e/pop-to-ESI -- cgit 1.4.1-2-gfad0