From f80a025e5267c0380e37753430fbd2ef90cd8602 Mon Sep 17 00:00:00 2001 From: nc Date: Thu, 4 Jul 2019 12:18:18 -0400 Subject: [PATCH] implement segment section in compute-offsets --- subx/apps/survey.subx | 115 ++++++++++++++++++++++++++++++++++++++++-- 1 file changed, 112 insertions(+), 3 deletions(-) diff --git a/subx/apps/survey.subx b/subx/apps/survey.subx index d8ebe3c4..9b9f763e 100644 --- a/subx/apps/survey.subx +++ b/subx/apps/survey.subx @@ -541,7 +541,7 @@ $compute-offsets:label: # . . push args 68/push 0x10/imm32/row-size 52/push-EDX - 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 . . . . 0x10/disp8 . # push *(EBP+16) # . . call e8/call get-or-insert/disp32 # . . discard args @@ -567,7 +567,6 @@ $compute-offsets:label: # continue 0f 84/jump-if-equal $compute-offsets:word-loop/disp32 $compute-offsets:segment: - # TODO: implement the rest of this block # if slice-equal?(word-slice/EDX, "==") # . EAX = slice-equal?(word-slice/EDX, "==") 68/push "=="/imm32 @@ -578,14 +577,110 @@ $compute-offsets:segment: # . EAX == 0 ? 3d/compare-EAX-and 0/imm32 # . if so, goto else - 74/jump-if-equal $compute-offsets:else/disp8 + 0f 84/jump-if-equal $compute-offsets:else/disp32 # . or fallthrough + # seg/EAX = get-or-insert(segments, curr-segment-name, row-size=16) + # . push args + 68/push 0x10/imm32/row-size + 68/push compute-offsets:curr-segment-name/imm32 + ff 6/subop/push 1/mod/*+disp8 5/rm32/EBP . . . . 0xc/disp8 . # push *(EBP+12) + # . call + e8/call get-or-insert/disp32 + # . discard args + 81 0/subop/add 3/mod/direct 4/rm32/ESP . . . . . 0xc/imm32 # add to ESP + # seg->size/EBX = file-offset - seg->starting-offset + # . save ECX + 51/push-ECX + # . EBX = *file-offset + 8b/copy 0/mod/indirect 5/rm32/.disp32 . . 3/r32/EBX compute-offsets:file-offset/disp32 # copy *file-offset to EBX + # . ECX = seg->starting-offset + 8b/copy 1/mod/*+disp8 0/rm32/EAX . . . 1/r32/EBX 4/disp8 . # copy *(EAX+4) to ECX + # . EBX -= ECX + 29/subtract 3/mod/direct 3/rm32/EBX . . . 1/r32/ECX . . # subtract ECX from EBX + # . seg->size = EBX + 89/copy 1/mod/*+disp8 0/rm32/EAX . . . 3/r32/EBX 8/disp8 . # copy EBX to *(EAX+8) + # . restore ECX + 59/pop-to-ECX + # trace-slsns("segment '", curr-segment-name, "' has size 0x", seg->size/EBX, "") + # . push args + 68/push "segment '"/imm32 + 68/push compute-offsets:curr-segment-name/imm32 + 68/push "' has size 0x"/imm32 + 53/push-EBX + 68/push ""/imm32 + # . call + e8/call trace-slsns/disp32 + # . discard args + 81 0/subop/add 3/mod/direct 4/rm32/ESP . . . . . 0x14/imm32 # add to ESP # next-word(line/ECX, curr-segment-name) 68/push compute-offsets:curr-segment-name/imm32 51/push-ECX e8/call next-word/disp32 # . discard args 81 0/subop/add 3/mod/direct 4/rm32/ESP . . . . . 8/imm32 # add to ESP + # if slice-empty?(curr-segment-name) abort + # . EAX = slice-empty?(curr-segment-name) + 68/push compute-offsets:curr-segment-name/imm32 + e8/call slice-empty?/disp32 + # . . discard args + 81 0/subop/add 3/mod/direct 4/rm32/ESP . . . . . 4/imm32 # add to ESP + # . EAX == 1 ? + 3d/compare-EAX-and 1/imm32 + # . if so, abort + 0f 84/jump-if-equal $compute-offsets:abort/disp32 + # segment-start/EBX = {0, 0} + 68/push 0/imm32 + 68/push 0/imm32 + 89/copy 3/mod/direct 3/rm32/EBX . . . 4/r32/ESP . . # copy ESP to EBX + # next-word(line/ECX, segment-start/EBX) + 53/push-EBX + 51/push-ECX + e8/call next-word/disp32 + # . discard args + 81 0/subop/add 3/mod/direct 4/rm32/ESP . . . . . 8/imm32 # add to ESP + # if slice-empty?(segment-start/EBX) abort + # . EAX = slice-empty?(segment-start/EBX) + 53/push-EBX + e8/call slice-empty?/disp32 + # . . discard args + 81 0/subop/add 3/mod/direct 4/rm32/ESP . . . . . 4/imm32 # add to ESP + # . EAX == 1 ? + 3d/compare-EAX-and 1/imm32 + # . if so, abort + 0f 84/jump-if-equal $compute-offsets:abort/disp32 + # save segment-start/EBX (and prep for parse-hex-int call) + 53/push-EBX + # seg/EBX = get-or-insert(segments, curr-segment-name, row-size=16) + # . push args + 68/push 0x10/imm32/row-size + 68/push compute-offsets:curr-segment-name/imm32 + ff 6/subop/push 1/mod/*+disp8 5/rm32/EBP . . . . 0xc/disp8 . # push *(EBP+12) + # . EBX = EAX + 89/copy 3/mod/direct 3/rm32/EBX . . . 0/r32/EAX . . # copy EAX to EBX + # seg->address = parse-hex-int(segment-start (already on stack)) + # . EAX = parse-hex-int(segment-start) + e8/call parse-hex-int/disp32 + # . . discard args + 81 0/subop/add 3/mod/direct 4/rm32/ESP . . . . . 4/imm32 # add to ESP + # . seg->address = EAX + 89/copy 0/mod/indirect 3/rm32/EBX . . . 0/r32/EAX . . # copy EAX to *EBX + # seg->file-offset = *file-offset/EAX + # . EAX = *file-offset + 8b/copy 0/mod/indirect 5/rm32/.disp32 . . 0/r32/EAX compute-offsets:file-offset/disp32 # copy *file-offset to EAX + 89/copy 1/mod/*+disp8 3/rm32/EBX . . . 0/r32/EAX 4/disp8 . # copy EAX to *(EBX+4) + # trace-slsns("segment '", curr-segment-name, "' has size 0x", seg->size/EBX, "") + # . push args + 68/push "segment '"/imm32 + 68/push compute-offsets:curr-segment-name/imm32 + 68/push "' is at file offset size 0x"/imm32 + 53/push-EAX + 68/push ""/imm32 + # . call + e8/call trace-slsns/disp32 + # . discard args + # segment-offset = 0 + c7 0/subop/copy 0/mod/indirect 5/rm32/.disp32 . . . compute-offsets:segment-offset/disp32 0/imm32 # copy to *segment-offset + eb/jump $compute-offsets:line-loop:break/disp8 $compute-offsets:else: # width/EAX = compute-width(word-slice/EDX) 52/push-EDX @@ -619,6 +714,20 @@ $compute-offsets:end: 89/copy 3/mod/direct 4/rm32/ESP . . . 5/r32/EBP . . # copy EBP to ESP 5d/pop-to-EBP c3/return +$compute-offsets:abort: + # . _write(2/stderr, error) + # . . push args + 68/push "'==' must be followed by segment name and segment-start\n"/imm32 + 68/push 2/imm32/stderr + # . . call + e8/call _write/disp32 + # . . discard args + 81 0/subop/add 3/mod/direct 4/rm32/ESP . . . . . 8/imm32 # add to ESP + # . syscall(exit, 1) + bb/copy-to-EBX 1/imm32 + b8/copy-to-EAX 1/imm32/exit + cd/syscall 0x80/imm8 + # never gets here test-compute-offsets: # input: