Mu - subx/056trace.subx

From 6e181e7fd998a0d542cb531c929c905a243ea2f6 Mon Sep 17 00:00:00 2001 From: Kartik Agaram Date: Tue, 5 Feb 2019 23:30:12 -0800 Subject: 4953 --- html/subx/056trace.subx.html | 423 +++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 423 insertions(+) create mode 100644 html/subx/056trace.subx.html (limited to 'html/subx/056trace.subx.html') diff --git a/html/subx/056trace.subx.html b/html/subx/056trace.subx.html new file mode 100644 index 00000000..7bffc6b4 --- /dev/null +++ b/html/subx/056trace.subx.html @@ -0,0 +1,423 @@ + + + + +Mu - subx/056trace.subx + + + + + + + + + + +https://github.com/akkartik/mu/blob/master/subx/056trace.subx +
+  1 # primitives for emitting traces to a 'trace' stream, and for tests to make assertions on its contents
+  2 #
+  3 # A trace stream looks like a regular stream:
+  4 #   write : int  # index at which writes go
+  5 #   read : int  # index that we've read until
+  6 #   data : (array byte)  # prefixed by length as usual
+  7 # In a real trace the data will be in a special segment set aside for the purpose.
+  8 #
+  9 # primitives for operating on traces:
+ 10 #   - initialize-trace-stream (update global variable)
+ 11 #   - trace: stream, string
+ 12 #   - die: stream (exit(1) if using real trace)
+ 13 #   - check-trace-contains: stream, string/line, string/message (scans only from stream's read pointer, prints message to stderr on failure, updates stream's read pointer)
+ 14 #   - scan-to-next-line: stream (advance read pointer past next newline)
+ 15 #
+ 16 # Traces are very fundamental, so many of the helpers we create here won't be
+ 17 # used elsewhere; we'll switch to more bounds-checked variants. But here we get
+ 18 # bounds-checking for free; we allocate a completely disjoint segment for trace
+ 19 # data, and overflowing it will generate a page fault.
+ 20 
+ 21 == data
+ 22 
+ 23 # We'll save the address of the trace segment here.
+ 24 Trace-stream:
+ 25     00 00 00 00
+ 26 
+ 27 # Fake trace-stream for tests.
+ 28 # Also illustrates the layout of the real trace-stream (segment).
+ 29 _test-trace-stream:
+ 30     # current write index
+ 31     00 00 00 00
+ 32     # current read index
+ 33     00 00 00 00
+ 34     # length (= 8)
+ 35     08 00 00 00
+ 36     # data
+ 37     00 00 00 00 00 00 00 00  # 8 bytes
+ 38 
+ 39 == code
+ 40 #   instruction                     effective address                                                   register    displacement    immediate
+ 41 # . op          subop               mod             rm32          base        index         scale       r32
+ 42 # . 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
+ 43 
+ 44 # main:
+ 45     # run-tests()
+ 46     e8/call  run-tests/disp32  # 'run-tests' is a function created automatically by SubX. It calls all functions that start with 'test-'.
+ 47     # syscall(exit, Num-test-failures)
+ 48     8b/copy                         0/mod/indirect  5/rm32/.disp32            .             .           3/r32/EBX   Num-test-failures/disp32          # copy *Num-test-failures to EBX
+ 49     b8/copy-to-EAX  1/imm32/exit
+ 50     cd/syscall  0x80/imm8
+ 51 
+ 52 # Allocate a new segment for the trace stream, initialize its length, and save its address to Trace-stream.
+ 53 # The Trace-stream segment will consist of variable-length lines separated by newlines (0x0a)
+ 54 initialize-trace-stream:
+ 55     # EAX = new-segment(0x1000)
+ 56     # . . push args
+ 57     68/push  0x1000/imm32/N
+ 58     # . . call
+ 59     e8/call  new-segment/disp32
+ 60     # . . discard args
+ 61     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+ 62     # copy EAX to *Trace-stream
+ 63     89/copy                         0/mod/indirect  5/rm32/.disp32            .             .           0/r32/EAX   Trace-stream/disp32               # copy EAX to *Trace-stream
+ 64     # Trace-stream->length = 0x1000/N - 12
+ 65     c7          0/subop/copy        1/mod/*+disp8   0/rm32/EAX    .           .             .           .           8/disp8         0xff4/imm32       # copy 0xff4 to *(EAX+8)
+ 66     c3/return
+ 67 
+ 68 # Append a string to the given trace stream.
+ 69 # Silently give up if it's already full. Or truncate the string if there isn't enough room.
+ 70 trace:  # t : (address trace-stream), line : string
+ 71     # . prolog
+ 72     55/push-EBP
+ 73     89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+ 74     # . save registers
+ 75     50/push-EAX
+ 76     51/push-ECX
+ 77     52/push-EDX
+ 78     53/push-EBX
+ 79     56/push-ESI
+ 80     57/push-EDI
+ 81     # EDI = t
+ 82     8b/copy                         1/mod/*+disp8   5/rm32/EBP    .           .                         7/r32/EDI   8/disp8         .                 # copy *(EBP+8) to EDI
+ 83     # ESI = line
+ 84     8b/copy                         1/mod/*+disp8   5/rm32/EBP    .           .                         6/r32/ESI   0xc/disp8       .                 # copy *(EBP+12) to ESI
+ 85     # ECX = t->write
+ 86     8b/copy                         0/mod/indirect  7/rm32/EDI    .           .             .           1/r32/ECX   .               .                 # copy *EDI to ECX
+ 87     # EDX = t->length
+ 88     8b/copy                         1/mod/*+disp8   7/rm32/EDI    .           .             .           2/r32/EDX   8/disp8         .                 # copy *(EDI+8) to EDX
+ 89     # EAX = _append-3(&t->data[t->write], &t->data[t->length], line)
+ 90     # . . push line
+ 91     56/push-ESI
+ 92     # . . push &t->data[t->length]
+ 93     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
+ 94     53/push-EBX
+ 95     # . . push &t->data[t->write]
+ 96     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
+ 97     53/push-EBX
+ 98     # . . call
+ 99     e8/call  _append-3/disp32
+100     # . . discard args
+101     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+102     # if EAX == 0 return
+103     81          7/subop/compare     3/mod/direct    0/rm32/EAX    .           .             .           .           .               0/imm32           # compare EDX
+104     74/jump-if-equal  $trace:end/disp8
+105     # t->write += EAX
+106     01/add                          0/mod/indirect  7/rm32/EDI    .           .             .           0/r32/EAX   .               .                 # add EAX to *EDI
+107     # refresh ECX = t->write
+108     8b/copy                         0/mod/indirect  7/rm32/EDI    .           .             .           1/r32/ECX   .               .                 # copy *EDI to ECX
+109     # EAX = _append-3(&t->data[t->write], &t->data[t->length], line)
+110     # . . push line
+111     68/push  Newline/imm32
+112     # . . push &t->data[t->length]
+113     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
+114     53/push-EBX
+115     # . . push &t->data[t->write]
+116     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
+117     53/push-EBX
+118     # . . call
+119     e8/call  _append-3/disp32
+120     # . . discard args
+121     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+122     # t->write += EAX
+123     01/add                          0/mod/indirect  7/rm32/EDI    .           .             .           0/r32/EAX   .               .                 # add EAX to *EDI
+124 $trace:end:
+125     # . restore registers
+126     5f/pop-to-EDI
+127     5e/pop-to-ESI
+128     5b/pop-to-EBX
+129     5a/pop-to-EDX
+130     59/pop-to-ECX
+131     58/pop-to-EAX
+132     # . epilog
+133     89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+134     5d/pop-to-EBP
+135     c3/return
+136 
+137 clear-trace-stream:  # t : (address trace-stream)
+138     # . prolog
+139     55/push-EBP
+140     89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+141     # . save registers
+142     50/push-EAX
+143     51/push-ECX
+144     # EAX = t
+145     8b/copy                         1/mod/*+disp8   5/rm32/EBP    .           .                         0/r32/EAX   8/disp8         .                 # copy *(EBP+8) to EAX
+146     # ECX = t->length
+147     8b/copy                         1/mod/*+disp8   0/rm32/EAX    .           .             .           1/r32/ECX   8/disp8         .                 # copy *(EAX+8) to ECX
+148     # ECX = &t->data[t->length]
+149     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
+150     # t->write = 0
+151     c7          0/subop/copy        0/mod/direct    0/rm32/EAX    .           .             .           .           .               0/imm32           # copy to *EAX
+152     # t->read = 0
+153     c7          0/subop/copy        1/mod/*+disp8   0/rm32/EAX    .           .             .           .           4/disp8         0/imm32           # copy to *(EAX+4)
+154     # EAX = t->data
+155     81          0/subop/add         3/mod/direct    0/rm32/EAX    .           .             .           .           .               0xc/imm32         # add to EAX
+156     # while (true)
+157 $clear-trace-stream:loop:
+158     # if EAX >= ECX break
+159     39/compare                      3/mod/direct    0/rm32/EAX    .           .             .           1/r32/ECX   .               .                 # compare EAX with ECX
+160     7d/jump-if-greater-or-equal  $clear-trace-stream:end/disp8
+161     # *EAX = 0
+162     c7          0/subop/copy        0/mod/direct    0/rm32/EAX    .           .             .           .           .               0/imm32           # copy to *EAX
+163     # EAX += 4
+164     81          0/subop/add         3/mod/direct    0/rm32/EAX    .           .             .           .           .               4/imm32           # add to EAX
+165     eb/jump  $clear-trace-stream:loop/disp8
+166 $clear-trace-stream:end:
+167     # . restore registers
+168     59/pop-to-ECX
+169     58/pop-to-EAX
+170     # . epilog
+171     89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+172     5d/pop-to-EBP
+173     c3/return
+174 
+175 # - tests
+176 
+177 test-trace-single:
+178     # clear-trace-stream(_test-trace-stream)
+179     # . . push args
+180     68/push  _test-trace-stream/imm32
+181     # . . call
+182     e8/call  clear-trace-stream/disp32
+183     # . . discard args
+184     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+185     # trace(_test-trace-stream, "Ab")
+186     # . . push args
+187     68/push  "Ab"/imm32
+188     68/push  _test-trace-stream/imm32
+189     # . . call
+190     e8/call  trace/disp32
+191     # . . discard args
+192     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+193     # check-ints-equal(*_test-trace-stream->data, 41/A 62/b 0a/newline 00, msg)
+194     # . . push args
+195     68/push  "F - test-trace-single"/imm32
+196     68/push  0x0a6241/imm32/Ab-newline
+197     # . . push *_test-trace-stream->data
+198     b8/copy-to-EAX  _test-trace-stream/imm32
+199     ff          6/subop/push        1/mod/*+disp8   0/rm32/EAX    .           .             .           .           0xc/disp8       .                 # push *(EAX+12)
+200     # . . call
+201     e8/call  check-ints-equal/disp32
+202     # . . discard args
+203     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+204     # end
+205     c3/return
+206 
+207 test-trace-appends:
+208     # clear-trace-stream(_test-trace-stream)
+209     # . . push args
+210     68/push  _test-trace-stream/imm32
+211     # . . call
+212     e8/call  clear-trace-stream/disp32
+213     # . . discard args
+214     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+215     # trace(_test-trace-stream, "C")
+216     # . . push args
+217     68/push  "C"/imm32
+218     68/push  _test-trace-stream/imm32
+219     # . . call
+220     e8/call  trace/disp32
+221     # . . discard args
+222     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+223     # trace(_test-trace-stream, "D")
+224     # . . push args
+225     68/push  "D"/imm32
+226     68/push  _test-trace-stream/imm32
+227     # . . call
+228     e8/call  trace/disp32
+229     # . . discard args
+230     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+231     # check-ints-equal(*_test-trace-stream->data, 43/C 0a/newline 44/D 0a/newline, msg)
+232     # . . push args
+233     68/push  "F - test-trace-appends"/imm32
+234     68/push  0x0a440a43/imm32/C-newline-D-newline
+235     # . . push *_test-trace-stream->data
+236     b8/copy-to-EAX  _test-trace-stream/imm32
+237     ff          6/subop/push        1/mod/*+disp8   0/rm32/EAX    .           .             .           .           0xc/disp8       .                 # push *(EAX+12)
+238     # . . call
+239     e8/call  check-ints-equal/disp32
+240     # . . discard args
+241     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+242     # end
+243     c3/return
+244 
+245 test-trace-empty-line:
+246     # clear-trace-stream(_test-trace-stream)
+247     # . . push args
+248     68/push  _test-trace-stream/imm32
+249     # . . call
+250     e8/call  clear-trace-stream/disp32
+251     # . . discard args
+252     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               4/imm32           # add to ESP
+253     # trace(_test-trace-stream, "")
+254     # . . push args
+255     68/push  ""/imm32
+256     68/push  _test-trace-stream/imm32
+257     # . . call
+258     e8/call  trace/disp32
+259     # . . discard args
+260     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               8/imm32           # add to ESP
+261     # check-ints-equal(*_test-trace-stream->data, 0, msg)
+262     # . . push args
+263     68/push  "F - test-trace-empty-line"/imm32
+264     68/push  0/imm32
+265     # . . push *_test-trace-stream->data
+266     b8/copy-to-EAX  _test-trace-stream/imm32
+267     ff          6/subop/push        1/mod/*+disp8   0/rm32/EAX    .           .             .           .           0xc/disp8       .                 # push *(EAX+12)
+268     # . . call
+269     e8/call  check-ints-equal/disp32
+270     # . . discard args
+271     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0xc/imm32         # add to ESP
+272     # end
+273     c3/return
+274 
+275 # - helpers
+276 
+277 # 3-argument variant of _append
+278 _append-3:  # out : address, outend : address, s : (array byte) -> num_bytes_appended/EAX
+279     # . prolog
+280     55/push-EBP
+281     89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+282     # . save registers
+283     51/push-ECX
+284     # _append-4(out, outend, &s->data[0], &s->data[s->length]) -> num_bytes_appended/EAX
+285     # . . push &s->data[s->length]
+286     8b/copy                         1/mod/*+disp8   5/rm32/EBP    .           .                         0/r32/EAX   0x10/disp8      .                 # copy *(EBP+16) to EAX
+287     8b/copy                         0/mod/indirect  0/rm32/EAX    .           .             .           1/r32/ECX   .               .                 # copy *EAX to ECX
+288     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
+289     51/push-ECX
+290     # . . push &s->data[0]
+291     8d/copy-address                 1/mod/*+disp8   0/rm32/EAX    .           .             .           1/r32/ECX   4/disp8         .                 # copy EAX+4 to ECX
+292     51/push-ECX
+293     # . . push outend
+294     ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           0xc/disp8       .                 # push *(EBP+12)
+295     # . . push out
+296     ff          6/subop/push        1/mod/*+disp8   5/rm32/EBP    .           .             .           .           8/disp8         .                 # push *(EBP+8)
+297     # . . call
+298     e8/call  _append-4/disp32
+299     # . . discard args
+300     81          0/subop/add         3/mod/direct    4/rm32/ESP    .           .             .           .           .               0x10/imm32        # add to ESP
+301 $_append-3:end:
+302     # . restore registers
+303     59/pop-to-ECX
+304     # . epilog
+305     89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+306     5d/pop-to-EBP
+307     c3/return
+308 
+309 # 4-argument variant of _append
+310 _append-4:  # out : address, outend : address, in : address, inend : address -> num_bytes_appended/EAX
+311     # . prolog
+312     55/push-EBP
+313     89/copy                         3/mod/direct    5/rm32/EBP    .           .             .           4/r32/ESP   .               .                 # copy ESP to EBP
+314     # . save registers
+315     51/push-ECX
+316     52/push-EDX
+317     53/push-EBX
+318     56/push-ESI
+319     57/push-EDI
+320     # EAX/num_bytes_appended = 0
+321     b8/copy-to-EAX  0/imm32
+322     # EDI = out
+323     8b/copy                         1/mod/*+disp8   5/rm32/EBP    .           .             .           7/r32/EDI   8/disp8         .                 # copy *(EBP+8) to EDI
+324     # EDX = outend
+325     8b/copy                         1/mod/*+disp8   5/rm32/EBP    .           .             .           2/r32/EDX   0xc/disp8       .                 # copy *(EBP+12) to EDX
+326     # ESI = in
+327     8b/copy                         1/mod/*+disp8   5/rm32/EBP    .           .             .           6/r32/ESI   0x10/disp8      .                 # copy *(EBP+16) to ESI
+328     # ECX = inend
+329     8b/copy                         1/mod/*+disp8   5/rm32/EBP    .           .             .           1/r32/ECX   0x14/disp8      .                 # copy *(EBP+20) to ECX
+330 $_append-4:loop:
+331     # if ESI/in >= ECX/inend break
+332     39/compare                      3/mod/direct    6/rm32/ESI    .           .             .           1/r32/ECX   .               .                 # compare ESI with ECX
+333     7d/jump-if-greater-or-equal  $_append-4:end/disp8
+334     # if EDI/out >= EDX/outend break  (for now silently ignore filled up buffer)
+335     39/compare                      3/mod/direct    7/rm32/EDI    .           .             .           2/r32/EDX   .               .                 # compare EDI with EDX
+336     7d/jump-if-greater-or-equal  $_append-4:end/disp8
+337     # copy one byte from ESI/in to EDI/out
+338     8a/copy-byte                    0/mod/indirect  6/rm32/ESI    .           .             .           3/r32/BL    .               .                 # copy byte at *ESI to BL
+339     88/copy-byte                    0/mod/indirect  7/rm32/EDI    .           .             .           3/r32/BL    .               .                 # copy byte at BL to *EDI
+340     # updates
+341     40/increment-EAX
+342     46/increment-ESI
+343     47/increment-EDI
+344     eb/jump  $_append-4:loop/disp8
+345 $_append-4:end:
+346     # . restore registers
+347     5f/pop-to-EDI
+348     5e/pop-to-ESI
+349     5b/pop-to-EBX
+350     5a/pop-to-EDX
+351     59/pop-to-ECX
+352     # . epilog
+353     89/copy                         3/mod/direct    4/rm32/ESP    .           .             .           5/r32/EBP   .               .                 # copy EBP to ESP
+354     5d/pop-to-EBP
+355     c3/return
+356 
+357 # . . vim:nowrap:textwidth=0
+
+ + + -- cgit 1.4.1-2-gfad0