# primitives for emitting traces to a 'trace' stream, and for tests to make assertions on its contents # # A trace stream looks like a regular stream: # write : int # index at which writes go # read : int # index that we've read until # data : (array byte) # prefixed by length as usual # Usually the trace stream will be in a separate segment set aside for the purpose. # # primitives for operating on traces (arguments in quotes): # - initialize-trace-stream: populates Trace-stream with a new segment of the given 'size' # - trace: adds a 'line' to Trace-stream # - check-trace-contains: scans from Trace-stream's start for a matching 'line', prints a 'message' to stderr on failure # - check-trace-scans-to: scans from Trace-stream's read pointer for a matching 'line', prints a 'message' to stderr on failure == data # We'll save the address of the trace segment here. Trace-stream: 0/imm32 Trace-segment: 0/imm32/curr 0/imm32/end # Fake trace-stream for tests. # Also illustrates the layout of the real trace-stream (segment). _test-trace-stream: # current write index 0/imm32 # current read index 0/imm32 # length 8/imm32 # data 00 00 00 00 00 00 00 00 # 8 bytes == 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 # Allocate a new segment for the trace stream, initialize its length, and save its address to Trace-stream. # The Trace-stream segment will consist of variable-length lines separated by newlines (0x0a) initialize-trace-stream: # n : int -> # . 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 # ECX = n 8b/copy 1/mod/*+disp8 5/rm32/EBP . . . 1/r32/ECX 8/disp8 . # copy *(EBP+8) to ECX # Trace-segment = new-segment(n) # . . push args 68/push Trace-segment/imm32 51/push-ECX # . . call e8/call new-segment/disp32 # . . discard args 81 0/subop/add 3/mod/direct 4/rm32/ESP . . . . . 8/imm32 # add to ESP # copy Trace-segment->curr to *Trace-stream 8b/copy 0/mod/indirect 5/rm32/.disp32 . . 0/r32/EAX Trace-segment/disp32 # copy *Trace-segment to EAX 89/copy 0/mod/indirect 5/rm32/.disp32 . . 0/r32/EAX Trace-stream/disp32 # copy EAX to *Trace-stream # Trace-stream->length = n - 12 # . ECX -= 12 81 5/subop/subtract 3/mod/direct 1/rm32/ECX . . . . . 0xc/imm32 # subtract from ECX # . Trace-stream->length = ECX 89/copy 1/mod/*+disp8 0/rm32/EAX . . . 1/r32/ECX 8/disp8 . # copy ECX to *(EAX+8) $initialize-trace-stream:end: # . restore registers 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 # Append a string to the given trace stream. # Silently give up if it's already full. Or truncate the string if there isn't enough room. trace: # line : (address string) # . 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 53/push-EBX 56/push-ESI 57/push-EDI # EDI = *Trace-stream 8b/copy 0/mod/indirect 5/rm32/.disp32 . . 7/r32/EDI Trace-stream/disp32 # copy *Trace-stream to EDI # ESI = line 8b/copy 1/mod/*+disp8 5/rm32/EBP . . 6/r32/ESI 8/disp8 . # copy *(EBP+8) to ESI # ECX = t->write 8b/copy 0/mod/indirect 7/rm32/EDI . . . 1/r32/ECX . . # copy *EDI to ECX # EDX = t->length 8b/copy 1/mod/*+disp8 7/rm32/EDI . . . 2/r32/EDX 8/disp8 . # copy *(EDI+8) to EDX # EAX = _append-3(&t->data[t->write], &t->data[t->length], line) # . . push line 56/push-ESI # . . push &t->data[t->length] 8d/copy-address 1/mod/*+disp8 4/rm32/sib 7/base/EDI 2/index/EDX . 3/r32/EBX 0xc/disp8 . # copy EDI+EDX+12 to EBX 53/push-EBX # . . push &t->data[t->write] 8d/copy-address 1/mod/*+disp8 4/rm32/sib 7/base/EDI 1/index/ECX . 3/r32/EBX 0xc/disp8 . # copy EDI+ECX+12 to EBX 53/push-EBX # . . call e8/call _append-3/disp32 # . . discard args 81 0/subop/add 3/mod/direct 4/rm32/ESP . . . . . 0xc/imm32 # add to ESP # if (EAX == 0) return 3d/compare-EAX-and 0/imm32 74/jump-if-equal $trace:end/disp8 # t->write += EAX 01/add 0/mod/indirect 7/rm32/EDI . . . 0/r32/EAX . . # add EAX to *EDI # refresh ECX = t->write 8b/copy 0/mod/indirect 7/rm32/EDI . . . 1/r32/ECX . . # copy *EDI to ECX # EAX = _append-3(&t->data[t->write], &t->data[t->length], line) # . . push line 68/push Newline/imm32 # . . push &t->data[t->length] 8d/copy-address 1/mod/*+disp8 4/rm32/sib 7/base/EDI 2/index/EDX . 3/r32/EBX 0xc/disp8 . # copy EDI+EDX+12 to EBX 53/push-EBX # . . push &t->data[t->write] 8d/copy-address 1/mod/*+disp8 4/rm32/sib 7/base/EDI 1/index/ECX . 3/r32/EBX 0xc/disp8 . # copy EDI+ECX+12 to EBX 53/push-EBX # . . call e8/call _append-3/disp32 # . . discard args 81 0/subop/add 3/mod/direct 4/rm32/ESP . . . . . 0xc/imm32 # add to ESP # t->write += EAX 01/add 0/mod/indirect 7/rm32/EDI . . . 0/r32/EAX . . # add EAX to *EDI $trace:end: # . restore registers 5f/pop-to-EDI 5e/pop-to-ESI 5b/pop-to-EBX 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-trace-single: # *Trace-stream = _test-trace-stream b8/copy-to-EAX _test-trace-stream/imm32 89/copy 0/mod/indirect 5/rm32/.disp32 . . 0/r32/EAX Trace-stream/disp32 # copy EAX to *Trace-stream # clear-trace-stream() e8/call clear-trace-stream/disp32 # trace("Ab") # . . push args 68/push "Ab"/imm32 # . . call e8/call trace/disp32 # . . discard args 81 0/subop/add 3/mod/direct 4/rm32/ESP . . . . . 4/imm32 # add to ESP # check-ints-equal(*_test-trace-stream->data, 41/A 62/b 0a/newline 00, msg) # . . push args 68/push "F - test-trace-single"/imm32 68/push 0x0a6241/imm32/Ab-newline # . . push *_test-trace-stream->data b8/copy-to-EAX _test-trace-stream/imm32 ff 6/subop/push 1/mod/*+disp8 0/rm32/EAX . . . . 0xc/disp8 . # push *(EAX+12) # . . 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-trace-appends: # *Trace-stream = _test-trace-stream b8/copy-to-EAX _test-trace-stream/imm32 89/copy 0/mod/indirect 5/rm32/.disp32 . . 0/r32/EAX Trace-stream/disp32 # copy EAX to *Trace-stream # clear-trace-stream() e8/call clear-trace-stream/disp32 # trace("C") # . . push args 68/push "C"/imm32 # . . call e8/call trace/disp32 # . . discard args 81 0/subop/add 3/mod/direct 4/rm32/ESP . . . . . 4/imm32 # add to ESP # trace("D") # . . push args 68/push "D"/imm32 # . . call e8/call trace/disp32 # . . discard args 81 0/subop/add 3/mod/direct 4/rm32/ESP . . . . . 4/imm32 # add to ESP # check-ints-equal(*_test-trace-stream->data, 43/C 0a/newline 44/D 0a/newline, msg) # . . push args 68/push "F - test-trace-appends"/imm32 68/push 0x0a440a43/imm32/C-newline-D-newline # . . push *_test-trace-stream->data b8/copy-to-EAX _test-trace-stream/imm32 ff 6/subop/push 1/mod/*+disp8 0/rm32/EAX . . . . 0xc/disp8 . # push *(EAX+12) # . . 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-trace-empty-line: # *Trace-stream = _test-trace-stream b8/copy-to-EAX _test-trace-stream/imm32 89/copy 0/mod/indirect 5/rm32/.disp32 . . 0/r32/EAX Trace-stream/disp32 # copy EAX to *Trace-stream # clear-trace-stream() e8/call clear-trace-stream/disp32 # trace("") # . . push args 68/push ""/imm32 # . . call e8/call trace/disp32 # . . discard args 81 0/subop/add 3/mod/direct 4/rm32/ESP . . . . . 4/imm32 # add to ESP # check-ints-equal(*_test-trace-stream->data, 0, msg) # . . push args 68/push "F - test-trace-empty-line"/imm32 68/push 0/imm32 # . . push *_test-trace-stream->data b8/copy-to-EAX _test-trace-stream/imm32 ff 6/subop/push 1/mod/*+disp8 0/rm32/EAX . . . . 0xc/disp8 . # push *(EAX+12) # . . 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 check-trace-contains: # line : (address string), msg : (address string) # . prolog 55/push-EBP 89/copy 3/mod/direct 5/rm32/EBP . . . 4/r32/ESP . . # copy ESP to EBP # rewind-stream(*Trace-stream) # . . push args ff 6/subop/push 0/mod/indirect 5/rm32/.disp32 . . . Trace-stream/disp32 # push *Trace-stream # . . call e8/call rewind-stream/disp32 # . . discard args 81 0/subop/add 3/mod/direct 4/rm32/ESP . . . . . 4/imm32 # add to ESP # check-trace-scans-to(line, msg) # . . 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 check-trace-scans-to/disp32 # . . discard args 81 0/subop/add 3/mod/direct 4/rm32/ESP . . . . . 8/imm32 # add to ESP $check-trace-contains:end: # . epilog 89/copy 3/mod/direct 4/rm32/ESP . . . 5/r32/EBP . . # copy EBP to ESP 5d/pop-to-EBP c3/return check-trace-scans-to: # line : (address string), msg : (address string) # . prolog 55/push-EBP 89/copy 3/mod/direct 5/rm32/EBP . . . 4/r32/ESP . . # copy ESP to EBP # . save registers 50/push-EAX # EAX = trace-scan(line) # . . push args ff 6/subop/push 1/mod/*+disp8 5/rm32/EBP . . . . 8/disp8 . # push *(EBP+8) # . . call e8/call trace-scan/disp32 # . . discard args 81 0/subop/add 3/mod/direct 4/rm32/ESP . . . . . 4/imm32 # add to ESP # check-ints-equal(EAX, 1, msg) # . . push args ff 6/subop/push 1/mod/*+disp8 5/rm32/EBP . . . . 0xc/disp8 . # push *(EBP+12) 68/push 1/imm32 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-trace-scans-to:end: # . restore registers 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 # Start scanning from Trace-stream->read for 'line'. If found, update Trace-stream->read and return true. trace-scan: # line : (address string) -> result/EAX : boolean # pseudocode: # push Trace-stream->read # while true: # if Trace-stream->read >= Trace-stream->write # break # if next-line-matches?(Trace-stream, line) # skip-next-line(Trace-stream) # dump saved copy of Trace-stream->read # return true # skip-next-line(Trace-stream) # pop saved copy of Trace-stream->read # return false # # . prolog 55/push-EBP 89/copy 3/mod/direct 5/rm32/EBP . . . 4/r32/ESP . . # copy ESP to EBP # . save registers 51/push-ECX 56/push-ESI # ESI = *Trace-stream 8b/copy 0/mod/indirect 5/rm32/.disp32 . . 6/r32/ESI Trace-stream/disp32 # copy *Trace-stream to ESI # ECX = Trace-stream->write 8b/copy 0/mod/indirect 6/rm32/ESI . . . 1/r32/ECX . # copy *ESI to ECX # push Trace-stream->read ff 6/subop/push 1/mod/*+disp8 6/rm32/ESI . . . . 4/disp8 . # push *(ESI+4) $trace-scan:loop: # if (Trace-stream->read >= Trace-stream->write) return false 39/compare 1/mod/*+disp8 6/rm32/ESI . . . 1/r32/ECX 4/disp8 . # compare ECX with *(ESI+4) 7d/jump-if-greater-or-equal $trace-scan:false/disp8 # EAX = next-line-matches?(Trace-stream, line) # . . push args ff 6/subop/push 1/mod/*+disp8 5/rm32/EBP . . . . 8/disp8 . # push *(EBP+8) 56/push-ESI # . . call e8/call next-line-matches?/disp32 # . . discard args 81 0/subop/add 3/mod/direct 4/rm32/ESP . . . . . 8/imm32 # add to ESP # if (EAX == 0) continue 3d/compare-EAX-and 0/imm32 74/jump-if-equal $trace-scan:continue/disp8 $trace-scan:true: # skip-next-line(Trace-stream) # . . push args 56/push-ESI # . . call e8/call skip-next-line/disp32 # . . discard args 81 0/subop/add 3/mod/direct 4/rm32/ESP . . . . . 4/imm32 # add to ESP # dump saved copy of Trace-stream->read 81 0/subop/add 3/mod/direct 4/rm32/ESP . . . . . 4/imm32 # add to ESP # return true b8/copy-to-EAX 1/imm32/true eb/jump $trace-scan:end/disp8 $trace-scan:continue: # skip-next-line(Trace-stream) # . . push args 56/push-ESI # . . call e8/call skip-next-line/disp32 # . . discard args 81 0/subop/add 3/mod/direct 4/rm32/ESP . . . . . 4/imm32 # add to ESP eb/jump $trace-scan:loop/disp8 $trace-scan:false: # restore saved copy of Trace-stream->read 8f 0/subop/pop 1/mod/*+disp8 6/rm32/ESI . . . . 4/disp8 . # pop to *(ESI+4) # return false b8/copy-to-EAX 0/imm32/false $trace-scan:end: # . 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 test-trace-scan-first: # setup # . *Trace-stream = _test-trace-stream b8/copy-to-EAX _test-trace-stream/imm32 89/copy 0/mod/indirect 5/rm32/.disp32 . . 0/r32/EAX Trace-stream/disp32 # copy EAX to *Trace-stream # . clear-trace-stream() e8/call clear-trace-stream/disp32 # . trace("Ab") # . . push args 68/push "Ab"/imm32 # . . call e8/call trace/disp32 # . . discard args 81 0/subop/add 3/mod/direct 4/rm32/ESP . . . . . 4/imm32 # add to ESP # EAX = trace-scan("Ab") # . . push args 68/push "Ab"/imm32 # . . call e8/call trace-scan/disp32 # . . discard args 81 0/subop/add 3/mod/direct 4/rm32/ESP . . . . . 4/imm32 # add to ESP # check-ints-equal(EAX, 1, msg) # . . push args 68/push "F - test-trace-scan-first"/imm32 68/push 1/imm32 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 # . end c3/return test-trace-scan-skips-lines-until-found: # setup # . *Trace-stream = _test-trace-stream b8/copy-to-EAX _test-trace-stream/imm32 89/copy 0/mod/indirect 5/rm32/.disp32 . . 0/r32/EAX Trace-stream/disp32 # copy EAX to *Trace-stream # . clear-trace-stream() e8/call clear-trace-stream/disp32 # . trace("Ab") # . . push args 68/push "Ab"/imm32 # . . call e8/call trace/disp32 # . . discard args 81 0/subop/add 3/mod/direct 4/rm32/ESP . . . . . 4/imm32 # add to ESP # . trace("cd") # . . push args 68/push "cd"/imm32 # . . call e8/call trace/disp32 # . . discard args 81 0/subop/add 3/mod/direct 4/rm32/ESP . . . . . 4/imm32 # add to ESP # EAX = trace-scan("cd") # . . push args 68/push "cd"/imm32 # . . call e8/call trace-scan/disp32 # . . discard args 81 0/subop/add 3/mod/direct 4/rm32/ESP . . . . . 4/imm32 # add to ESP # check-ints-equal(EAX, 1, msg) # . . push args 68/push "F - test-trace-scan-skips-lines-until-found"/imm32 68/push 1/imm32 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 # . end c3/return test-trace-second-scan-starts-where-first-left-off: # setup # . *Trace-stream = _test-trace-stream b8/copy-to-EAX _test-trace-stream/imm32 89/copy 0/mod/indirect 5/rm32/.disp32 . . 0/r32/EAX Trace-stream/disp32 # copy EAX to *Trace-stream # . clear-trace-stream() e8/call clear-trace-stream/disp32 # . trace("Ab") # . . push args 68/push "Ab"/imm32 # . . call e8/call trace/disp32 # . . discard args 81 0/subop/add 3/mod/direct 4/rm32/ESP . . . . . 4/imm32 # add to ESP # . EAX = trace-scan("Ab") # . . push args 68/push "Ab"/imm32 # . . call e8/call trace-scan/disp32 # . . discard args 81 0/subop/add 3/mod/direct 4/rm32/ESP . . . . . 4/imm32 # add to ESP # second scan fails # . EAX = trace-scan("Ab") # . . push args 68/push "Ab"/imm32 # . . call e8/call trace-scan/disp32 # . . discard args 81 0/subop/add 3/mod/direct 4/rm32/ESP . . . . . 4/imm32 # add to ESP # check-ints-equal(EAX, 0, msg) # . . push args 68/push "F - test-trace-second-scan-starts-where-first-left-off"/imm32 68/push 0/imm32 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 # . end c3/return test-trace-scan-failure-leaves-read-index-untouched: # setup # . *Trace-stream = _test-trace-stream b8/copy-to-EAX _test-trace-stream/imm32 89/copy 0/mod/indirect 5/rm32/.disp32 . . 0/r32/EAX Trace-stream/disp32 # copy EAX to *Trace-stream # . clear-trace-stream() e8/call clear-trace-stream/disp32 # . trace("Ab") # . . push args 68/push "Ab"/imm32 # . . call e8/call trace/disp32 # . . discard args 81 0/subop/add 3/mod/direct 4/rm32/ESP . . . . . 4/imm32 # add to ESP # . check-ints-equal(_test-trace-stream->read, 0, msg) # . . push args 68/push "F - test-trace-second-scan-starts-where-first-left-off/precondition-failure"/imm32 68/push 0/imm32 b8/copy-to-EAX _test-trace-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 # perform a failing scan # . EAX = trace-scan("Ax") # . . push args 68/push "Ax"/imm32 # . . call e8/call trace-scan/disp32 # . . discard args 81 0/subop/add 3/mod/direct 4/rm32/ESP . . . . . 4/imm32 # add to ESP # no change in read index # . check-ints-equal(_test-trace-stream->read, 0, msg) # . . push args 68/push "F - test-trace-second-scan-starts-where-first-left-off"/imm32 68/push 0/imm32 b8/copy-to-EAX _test-trace-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 next-line-matches?: # t : (address stream), line : (address string) -> result/EAX : boolean # pseudocode: # while true: # if (currl >= maxl) break # if (currt >= maxt) return false # if (*currt != *currl) return false # ++currt # ++currl # return *currt == '\n' # # . prolog 55/push-EBP 89/copy 3/mod/direct 5/rm32/EBP . . . 4/r32/ESP . . # copy ESP to EBP # . save registers 51/push-ECX 52/push-EDX 53/push-EBX 56/push-ESI 57/push-EDI # EDX = line 8b/copy 1/mod/*+disp8 5/rm32/EBP . . 2/r32/EDX 0xc/disp8 . # copy *(EBP+12) to EDX # currl/ESI = line->data # . ESI = line/EDX->data 8d/copy-address 1/mod/*+disp8 2/rm32/EDX . . . 6/r32/ESI 4/disp8 . # copy EDX+4 to ESI # maxl/ECX = line->data + line->size # . EAX = line/EDX->size 8b/copy 0/mod/indirect 2/rm32/EDX . . 0/r32/EAX . . # copy *EDX to EAX # . maxl/ECX = line->data/ESI + line->size/EAX 8d/copy-address 0/mod/indirect 4/rm32/sib 6/base/ESI 0/index/EAX . 1/r32/ECX . . # copy EDX+EAX to ECX # EDI = t 8b/copy 1/mod/*+disp8 5/rm32/EBP . . 7/r32/EDI 8/disp8 . # copy *(EBP+8) to EDI # EBX = t->data 8d/copy-address 1/mod/*+disp8 7/rm32/EDI . . . 3/r32/EBX 0xc/disp8 . # copy EDI+12 to EBX # maxt/EDX = t->data + t->write # . EAX = t->write 8b/copy 0/mod/indirect 7/rm32/EDI . . 0/r32/EAX . . # copy *EDI to EAX # . maxt/EDX = t->data/EBX + t->write/EAX 8d/copy-address 0/mod/indirect 4/rm32/sib 3/base/EBX 0/index/EAX . 2/r32/EDX . . # copy EBX+EAX to EDX # currt/EDI = t->data + t->read # . EAX = t/EDI->read 8b/copy 1/mod/*+disp8 7/rm32/EDI . . 0/r32/EAX 4/disp8 . # copy *(EDI+4) to EAX # . currt/EDI = t->data/EBX + t->read/EAX 8d/copy-address 0/mod/indirect 4/rm32/sib 3/base/EBX 0/index/EAX . 7/r32/EDI . . # copy EBX+EAX to EDI $next-line-matches?:loop: # if (currl/ESI >= maxl/ECX) break 39/compare 3/mod/direct 6/rm32/ESI . . . 1/r32/ECX . . # compare ESI and ECX 73/jump-if-greater-or-equal-unsigned $next-line-matches?:break/disp8 # if (currt/EDI >= maxt/EDX) return false # . EAX = false b8/copy-to-EAX 0/imm32/false 39/compare 3/mod/direct 7/rm32/EDI . . . 2/r32/EDX . . # compare EDI and EDX 73/jump-if-greater-or-equal-unsigned $next-line-matches?:end/disp8 # if (*currt/EDI != *currl/ESI) return false 31/xor 3/mod/direct 0/rm32/EAX . . . 0/r32/EAX . . # clear EAX 31/xor 3/mod/direct 3/rm32/EAX . . . 3/r32/EAX . . # clear EBX # . EAX = (char) *currt/EDI 8a/copy-byte 0/mod/indirect 7/rm32/EDI . . 0/r32/EAX . . # copy *EDI to EAX # . EBX = (char) *currl/ESI 8a/copy-byte 0/mod/indirect 6/rm32/ESI . . 3/r32/EBX . . # copy *ESI to EBX # . EAX >= EBX 39/compare 3/mod/direct 0/rm32/EAX . . . 3/r32/EBX . . # compare EAX and EBX # . EAX = false b8/copy-to-EAX 0/imm32/false 75/jump-if-not-equal $next-line-matches?:end/disp8 # ++currt/EDI 47/increment-EDI # ++currl/ESI 46/increment-ESI eb/jump $next-line-matches?:loop/disp8 $next-line-matches?:break: # return *currt == '\n' 31/xor 3/mod/direct 0/rm32/EAX . . . 0/r32/EAX . . # clear EAX # . EAX = (char) *currt 8a/copy-byte 0/mod/indirect 7/rm32/EDI . . 0/r32/EAX . . # copy *EDI to EAX 3d/compare-EAX-and 0xa/imm32/newline # . EAX = false b8/copy-to-EAX 1/imm32/true 74/jump-if-equal $next-line-matches?:end/disp8 b8/copy-to-EAX 0/imm32/true $next-line-matches?:end: # . restore registers 5f/pop-to-EDI 5e/pop-to-ESI 5b/pop-to-EBX 5a/pop-to-EDX 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 test-next-line-matches?-no-match-1: # next line of "ABABA" does not match "blah blah" # . EAX = next-line-matches?(_test-stream-line-ABABA, "blah blah") # . . push args 68/push "blah blah"/imm32 68/push _test-stream-line-ABABA/imm32 # . . call e8/call next-line-matches?/disp32 # . . discard args 81 0/subop/add 3/mod/direct 4/rm32/ESP . . . . . 8/imm32 # add to ESP # . check-ints-equal(EAX, 0, msg) # . . push args 68/push "F - test-next-line-matches?-no-match-1"/imm32 68/push 0/imm32 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 c3/return test-next-line-matches?-no-match-2: # next line of "ABABA" does not match "" # . EAX = next-line-matches?(_test-stream-line-ABABA, "") # . . push args 68/push ""/imm32 68/push _test-stream-line-ABABA/imm32 # . . call e8/call next-line-matches?/disp32 # . . discard args 81 0/subop/add 3/mod/direct 4/rm32/ESP . . . . . 8/imm32 # add to ESP # . check-ints-equal(EAX, 0, msg) # . . push args 68/push "F - test-next-line-matches?-no-match-2"/imm32 68/push 0/imm32 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 c3/return test-next-line-matches?-no-match-3: # next line of "ABABA" does not match "AA" # . EAX = next-line-matches?(_test-stream-line-ABABA, "AA") # . . push args 68/push "AA"/imm32 68/push _test-stream-line-ABABA/imm32 # . . call e8/call next-line-matches?/disp32 # . . discard args 81 0/subop/add 3/mod/direct 4/rm32/ESP . . . . . 8/imm32 # add to ESP # . check-ints-equal(EAX, 0, msg) # . . push args 68/push "F - test-next-line-matches?-no-match-3"/imm32 68/push 0/imm32 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 c3/return test-next-line-matches?-match: # next line of "ABABA" matches "ABABA" # . EAX = next-line-matches?(_test-stream-line-ABABA, "ABABA") # . . push args 68/push "ABABA"/imm32 68/push _test-stream-line-ABABA/imm32 # . . call e8/call next-line-matches?/disp32 # . . discard args 81 0/subop/add 3/mod/direct 4/rm32/ESP . . . . . 8/imm32 # add to ESP # . check-ints-equal(EAX, 1, msg) # . . push args 68/push "F - test-next-line-matches?-match"/imm32 68/push 1/imm32 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 c3/return # move t->read to _after_ next newline skip-next-line: # t : (address stream) # pseudocode: # max = t->data + t->write # i = t->read # curr = t->data + t->read # while true # if (curr >= max) break # ++i # if (*curr == '\n') break # ++curr # t->read = i # # . 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 53/push-EBX # ECX = t 8b/copy 1/mod/*+disp8 5/rm32/EBP . . 1/r32/ECX 8/disp8 . # copy *(EBP+8) to ECX # EDX = t/ECX->data 8d/copy-address 1/mod/*+disp8 1/rm32/ECX . . . 2/r32/EDX 0xc/disp8 . # copy ECX+12 to EDX # EAX = t/ECX->write 8b/copy 0/mod/indirect 1/rm32/ECX . . . 0/r32/EAX . . # copy *ECX to EAX # max/EBX = t->data/EDX + t->write/EAX 8d/copy-address 0/mod/indirect 4/rm32/sib 2/base/EDX 0/index/EAX . 3/r32/EBX . . # copy EDX+EAX to EBX # EAX = t/ECX->read 8b/copy 1/mod/*+disp8 1/rm32/ECX . . . 0/r32/EAX 4/disp8 . # copy *(ECX+4) to EDX # curr/ECX = t->data/EDX + t->read/EAX 8d/copy-address 0/mod/indirect 4/rm32/sib 2/base/EDX 0/index/EAX . 1/r32/ECX . . # copy EDX+EAX to ECX # i/EDX = EAX 8b/copy 3/mod/direct 0/rm32/EAX . . . 2/r32/EDX . . # copy EAX to EDX $skip-next-line:loop: # if (curr/ECX >= max/EBX) break 39/compare 3/mod/direct 1/rm32/ECX . . . 3/r32/EBX . . # compare ECX and EBX 73/jump-if-greater-or-equal-unsigned $skip-next-line:end/disp8 # ++i/EDX 42/increment-EDX # if (*curr/ECX == '\n') break 31/xor 3/mod/direct 0/rm32/EAX . . . 0/r32/EAX . . # clear EAX 8a/copy-byte 0/mod/indirect 1/rm32/ECX . . . 0/r32/EAX . . # copy *ECX to EAX 3d/compare-EAX-and 0a/imm32/newline 74/jump-if-equal $skip-next-line:end/disp8 # ++curr/ECX 41/increment-ECX # loop eb/jump $skip-next-line:loop/disp8 $skip-next-line:end: # ECX = t 8b/copy 1/mod/*+disp8 5/rm32/EBP . . 1/r32/ECX 8/disp8 . # copy *(EBP+8) to ECX # t/ECX->read = i/EDX 89/copy 1/mod/*+disp8 1/rm32/ECX . . . 2/r32/EDX 4/disp8 . # copy EDX to *(ECX+4) # . restore registers 5b/pop-to-EBX 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-next-line-empty: # skipping next line in empty stream leaves read pointer at 0 # . skip-next-line(_test-stream-empty) # . . push args 68/push _test-stream-empty/imm32 # . . call e8/call skip-next-line/disp32 # . . discard args 81 0/subop/add 3/mod/direct 4/rm32/ESP . . . . . 4/imm32 # add to ESP # . check-ints-equal(_test-stream-empty->read, 0, msg) # . . push args 68/push "F - test-skip-next-line-empty"/imm32 68/push 0/imm32 b8/copy-to-EAX _test-stream-empty/imm32 8b/copy 1/mod/*+disp8 0/rm32/EAX . . . 0/r32/EAX 4/disp8 . # copy *(EAX+4) to 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 c3/return test-skip-next-line-filled: # skipping next line increments read pointer by length of line + 1 (for newline) # . skip-next-line(_test-stream-filled) # . . push args 68/push _test-stream-filled/imm32 # . . call e8/call skip-next-line/disp32 # . . discard args 81 0/subop/add 3/mod/direct 4/rm32/ESP . . . . . 4/imm32 # add to ESP # . check-ints-equal(_test-stream-filled->read, 5, msg) # . . push args 68/push "F - test-skip-next-line-filled"/imm32 68/push 5/imm32 b8/copy-to-EAX _test-stream-filled/imm32 8b/copy 1/mod/*+disp8 0/rm32/EAX . . . 0/r32/EAX 4/disp8 . # copy *(EAX+4) to 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 c3/return clear-trace-stream: # . 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 # EAX = *Trace-stream 8b/copy 0/mod/indirect 5/rm32/.disp32 . . 0/r32/EAX Trace-stream/disp32 # copy *Trace-stream to EAX # ECX = t->length 8b/copy 1/mod/*+disp8 0/rm32/EAX . . . 1/r32/ECX 8/disp8 . # copy *(EAX+8) to ECX # ECX = &t->data[t->length] 8d/copy-address 1/mod/*+disp8 4/rm32/sib 0/base/EAX 1/index/ECX . 1/r32/ECX 0xc/disp8 . # copy EAX+ECX+12 to ECX # t->write = 0 c7 0/subop/copy 0/mod/direct 0/rm32/EAX . . . . . 0/imm32 # copy to *EAX # t->read = 0 c7 0/subop/copy 1/mod/*+disp8 0/rm32/EAX . . . . 4/disp8 0/imm32 # copy to *(EAX+4) # EAX = t->data 81 0/subop/add 3/mod/direct 0/rm32/EAX . . . . . 0xc/imm32 # add to EAX $clear-trace-stream:loop: # if (EAX >= ECX) break 39/compare 3/mod/direct 0/rm32/EAX . . . 1/r32/ECX . . # compare EAX with ECX 73/jump-if-greater-or-equal-unsigned $clear-trace-stream:end/disp8 # *EAX = 0 c7 0/subop/copy 0/mod/direct 0/rm32/EAX . . . . . 0/imm32 # copy to *EAX # EAX += 4 81 0/subop/add 3/mod/direct 0/rm32/EAX . . . . . 4/imm32 # add to EAX eb/jump $clear-trace-stream:loop/disp8 $clear-trace-stream:end: # . restore registers 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 # - helpers # 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 # EAX = _append-4(out, outend, &s->data[0], &s->data[s->length]) # . . push &s->data[s->length] 8b/copy 1/mod/*+disp8 5/rm32/EBP . . 0/r32/EAX 0x10/disp8 . # copy *(EBP+16) to EAX 8b/copy 0/mod/indirect 0/rm32/EAX . . . 1/r32/ECX . . # copy *EAX to ECX 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 5/rm32/EBP . . . . 0xc/disp8 . # push *(EBP+12) # . . push out ff 6/subop/push 1/mod/*+disp8 5/rm32/EBP . . . . 8/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 $_append-3:end: # . 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 # . save registers 51/push-ECX 52/push-EDX 53/push-EBX 56/push-ESI 57/push-EDI # EAX/num_bytes_appended = 0 b8/copy-to-EAX 0/imm32 # EDI = out 8b/copy 1/mod/*+disp8 5/rm32/EBP . . . 7/r32/EDI 8/disp8 . # copy *(EBP+8) to EDI # EDX = outend 8b/copy 1/mod/*+disp8 5/rm32/EBP . . . 2/r32/EDX 0xc/disp8 . # copy *(EBP+12) to EDX # ESI = in 8b/copy 1/mod/*+disp8 5/rm32/EBP . . . 6/r32/ESI 0x10/disp8 . # copy *(EBP+16) to ESI # ECX = inend 8b/copy 1/mod/*+disp8 5/rm32/EBP . . . 1/r32/ECX 0x14/disp8 . # copy *(EBP+20) to ECX $_append-4:loop: # if (in >= inend) break 39/compare 3/mod/direct 6/rm32/ESI . . . 1/r32/ECX . . # compare ESI with ECX 73/jump-if-greater-or-equal-unsigned $_append-4:end/disp8 # if (out >= outend) abort # just to catch test failures fast 39/compare 3/mod/direct 7/rm32/EDI . . . 2/r32/EDX . . # compare EDI with EDX 73/jump-if-greater-or-equal-unsigned $_append-4:abort/disp8 # *out = *in 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 # ++num_bytes_appended 40/increment-EAX # ++in 46/increment-ESI # ++out 47/increment-EDI eb/jump $_append-4:loop/disp8 $_append-4:end: # . restore registers 5f/pop-to-EDI 5e/pop-to-ESI 5b/pop-to-EBX 5a/pop-to-EDX 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 $_append-4:abort: # . _write(2/stderr, error) # . . push args 68/push "stream overflow"/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 == data _test-stream-line-ABABA: # write 8/imm32 # read 0/imm32 # length 8/imm32 # data 41 42 41 42 41 0A 00 00 # 8 bytes _test-stream-empty: # write 0/imm32 # read 0/imm32 # length 8/imm32 # data 00 00 00 00 00 00 00 00 # 8 bytes _test-stream-filled: # write 8/imm32 # read 0/imm32 # length 8/imm32 # data 41 41 41 41 0A 41 41 41 # 8 bytes # . . vim:nowrap:textwidth=0