1 # write-stream: like write, but write streams rather than strings
  2 
  3 == code
  4 #   instruction                     effective address                                                   register    displacement    immediate
  5 # . op          subop               mod             rm32          base        index         scale       r32
  6 # . 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
  7 
  8 write-stream:  # f: (addr stream byte), s: (addr stream byte)
  9     # . prologue
 10     55/push-ebp
 11     89/copy                         3/mod/direct    5/rm32/ebp    .           .             .           4/r32/esp   .               .                 # copy esp to ebp
 12     # . save registers
 13     50/push-eax
 14     56/push-esi
 15     57/push-edi
 16     # edi = f
 17     8b/copy                         1/mod/*+disp8   5/rm32/ebp    .           .                         7/r32/edi   8/disp8         .                 # copy *(ebp+8) to edi
 18     # esi = s
 19     8b/copy                         1/mod/*+disp8   5/rm32/ebp    .           .                         6/r32/esi   0xc/disp8       .                 # copy *(ebp+12) to esi
 20     # eax = _append-4(&f->data[f->write], &f->data[f->size], &s->data[s->read], &s->data[s->write])
 21     # . . push &s->data[s->write]
 22     8b/copy                         0/mod/indirect  6/rm32/esi    .           .             .           0/r32/eax   .               .                 # copy *esi to eax
 23     8d/copy-address                 1/mod/*+disp8   4/rm32/sib    6/base/esi  0/index/eax   .           0/r32/eax   0xc/disp8       .                 # copy esi+eax+12 to eax
 24     50/push-eax
 25     # . . push &s->data[s->read]
 26     8b/copy                         1/mod/*+disp8   6/rm32/esi    .           .             .           0/r32/eax   4/disp8         .                 # copy *(esi+4) to eax
 27     8d/copy-address                 1/mod/*+disp8   4/rm32/sib    6/base/esi  0/index/eax   .           0/r32/eax   0xc/disp8       .                 # copy esi+eax+12 to eax
 28     50/push-eax
 29     # . . push &f->data[f->size]
 30     8b/copy                         1/mod/*+disp8   7/rm32/edi    .           .             .           0/r32/eax   8/disp8         .                 # copy *(edi+8) to eax
 31     8d/copy-address                 1/mod/*+disp8   4/rm32/sib    7/base/edi  0/index/eax   .           0/r32/eax   0xc/disp8       .                 # copy edi+eax+12 to eax
 32     50/push-eax
 33     # . . push &f->data[f->write]
 34     8b/copy                         0/mod/indirect  7/rm32/edi    .           .             .           0/r32/eax   .               .                 # copy *edi to eax
 35     8d/copy-address                 1/mod/*+disp8   4/rm32/sib    7/base/edi  0/index/eax   .           0/r32/eax   0xc/disp8       .                 # copy edi+eax+12 to eax
 36     50/push-eax
 37     # . . call
 38     e8/call  _append-4/disp32
 39     # . . discard args
 40     81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               0x10/imm32        # add to esp
 41     # f->write += eax
 42     01/add                          0/mod/indirect  7/rm32/edi    .           .             .           0/r32/eax   .               .                 # add eax to *edi
 43     # s->read += eax
 44     01/add                          1/mod/*+disp8   6/rm32/esi    .           .             .           0/r32/eax   4/disp8         .                 # add eax to *(esi+4)
 45 $write-stream:end:
 46     # . restore registers
 47     5f/pop-to-edi
 48     5e/pop-to-esi
 49     58/pop-to-eax
 50     # . epilogue
 51     89/copy                         3/mod/direct    4/rm32/esp    .           .             .           5/r32/ebp   .               .                 # copy ebp to esp
 52     5d/pop-to-ebp
 53     c3/return
 54 
 55 test-write-stream-single:
 56     # setup
 57     # . clear-stream(_test-stream)
 58     # . . push args
 59     68/push  _test-stream/imm32
 60     # . . call
 61     e8/call  clear-stream/disp32
 62     # . . discard args
 63     81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               4/imm32           # add to esp
 64     # . clear-stream(_test-stream2)
 65     # . . push args
 66     68/push  _test-stream2/imm32
 67     # . . call
 68     e8/call  clear-stream/disp32
 69     # . . discard args
 70     81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               4/imm32           # add to esp
 71     # . write(_test-stream2, "Ab")
 72     # . . push args
 73     68/push  "Ab"/imm32
 74     68/push  _test-stream2/imm32
 75     # . . call
 76     e8/call  write/disp32
 77     # . . discard args
 78     81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
 79     # write-stream(_test-stream, _test-stream2)
 80     # . . push args
 81     68/push  _test-stream2/imm32
 82     68/push  _test-stream/imm32
 83     # . . call
 84     e8/call  write-stream/disp32
 85     # . . discard args
 86     81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
 87     # check-stream-equal(_test-stream, "Ab", msg)
 88     # . . push args
 89     68/push  "F - test-write-stream-single"/imm32
 90     68/push  "Ab"/imm32
 91     68/push  _test-stream/imm32
 92     # . . call
 93     e8/call  check-stream-equal/disp32
 94     # . . discard args
 95     81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               0xc/imm32         # add to esp
 96     # . end
 97     c3/return
 98 
 99 test-write-stream-appends:
100     # setup
101     # . clear-stream(_test-stream)
102     # . . push args
103     68/push  _test-stream/imm32
104     # . . call
105     e8/call  clear-stream/disp32
106     # . . discard args
107     81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               4/imm32           # add to esp
108     # . clear-stream(_test-stream2)
109     # . . push args
110     68/push  _test-stream2/imm32
111     # . . call
112     e8/call  clear-stream/disp32
113     # . . discard args
114     81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               4/imm32           # add to esp
115     # . write(_test-stream2, "C")
116     # . . push args
117     68/push  "C"/imm32
118     68/push  _test-stream2/imm32
119     # . . call
120     e8/call  write/disp32
121     # . . discard args
122     81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
123     # first write
124     # . write-stream(_test-stream, _test-stream2)
125     # . . push args
126     68/push  _test-stream2/imm32
127     68/push  _test-stream/imm32
128     # . . call
129     e8/call  write-stream/disp32
130     # . . discard args
131     81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
132     # second write
133     # . write(_test-stream2, "D")
134     # . . push args
135     68/push  "D"/imm32
136     68/push  _test-stream2/imm32
137     # . . call
138     e8/call  write/disp32
139     # . . discard args
140     81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
141     # . write-stream(_test-stream, _test-stream2)
142     # . . push args
143     68/push  _test-stream2/imm32
144     68/push  _test-stream/imm32
145     # . . call
146     e8/call  write-stream/disp32
147     # . . discard args
148     81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
149     # check-stream-equal(_test-stream, "CD", msg)
150     # . . push args
151     68/push  "F - test-write-stream-appends"/imm32
152     68/push  "CD"/imm32
153     68/push  _test-stream/imm32
154     # . . call
155     e8/call  check-stream-equal/disp32
156     # . . discard args
157     81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               0xc/imm32         # add to esp
158     # . end
159     c3/return
160 
161 == data
162 
163 _test-stream2:  # (stream byte)
164     # current write index
165     4/imm32
166     # current read index
167     1/imm32
168     # size
169     8/imm32
170     # data
171     41/A 42/B 43/C 44/D 00 00 00 00  # 8 bytes
172 
173 # . . vim:nowrap:textwidth=0