about summary refs log tree commit diff stats
path: root/html/x.mu.html
diff options
context:
space:
mode:
Diffstat (limited to 'html/x.mu.html')
0 files changed, 0 insertions, 0 deletions
>50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252
# write-stream: like write, but write streams rather than strings

== 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

#? Entry:  # manual test
#?     # write-stream(stdout, _test-stream2)
#?     68/push  _test-stream2/imm32
#?     68/push  1/imm32/stdout
#?     e8/call write-stream/disp32
#?     # syscall_exit(Num-test-failures)
#?     8b/copy                         0/mod/indirect  5/rm32/.disp32            .             .           3/r32/ebx   Num-test-failures/disp32          # copy *Num-test-failures to ebx
#?     e8/call  syscall_exit/disp32

write-stream:  # f: fd or (addr stream byte), s: (addr stream byte)
    # . prologue
    55/push-ebp
    89/copy                         3/mod/direct    5/rm32/ebp    .           .             .           4/r32/esp   .               .                 # copy esp to ebp
    # if (f < 0x08000000) _write-stream(f, s), return  # f can't be a user-mode address, so treat it as a kernel file descriptor
    81          7/subop/compare     1/mod/*+disp8   5/rm32/ebp    .           .             .           .           8/disp8         0x08000000/imm32  # compare *(ebp+8)
    73/jump-if-addr>=  $write-stream:fake/disp8
    # . . 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  _write-stream/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
    eb/jump  $write-stream:end/disp8
$write-stream:fake:
    # otherwise, treat 'f' as a stream to append to
    # . save registers
    50/push-eax
    56/push-esi
    57/push-edi
    # edi = f
    8b/copy                         1/mod/*+disp8   5/rm32/ebp    .           .                         7/r32/edi   8/disp8         .                 # copy *(ebp+8) to edi
    # esi = s
    8b/copy                         1/mod/*+disp8   5/rm32/ebp    .           .                         6/r32/esi   0xc/disp8       .                 # copy *(ebp+12) to esi
    # eax = _append-4(&f->data[f->write], &f->data[f->size], &s->data[s->read], &s->data[s->write])
    # . . push &s->data[s->write]
    8b/copy                         0/mod/indirect  6/rm32/esi    .           .             .           0/r32/eax   .               .                 # copy *esi to eax
    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
    50/push-eax
    # . . push &s->data[s->read]
    8b/copy                         1/mod/*+disp8   6/rm32/esi    .           .             .           0/r32/eax   4/disp8         .                 # copy *(esi+4) to eax
    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
    50/push-eax
    # . . push &f->data[f->size]
    8b/copy                         1/mod/*+disp8   7/rm32/edi    .           .             .           0/r32/eax   8/disp8         .                 # copy *(edi+8) to eax
    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
    50/push-eax
    # . . push &f->data[f->write]
    8b/copy                         0/mod/indirect  7/rm32/edi    .           .             .           0/r32/eax   .               .                 # copy *edi to eax
    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
    50/push-eax
    # . . call
    e8/call  _append-4/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               0x10/imm32        # add to esp
    # f->write += eax
    01/add                          0/mod/indirect  7/rm32/edi    .           .             .           0/r32/eax   .               .                 # add eax to *edi
    # s->read += eax
    01/add                          1/mod/*+disp8   6/rm32/esi    .           .             .           0/r32/eax   4/disp8         .                 # add eax to *(esi+4)
    # . restore registers
    5f/pop-to-edi
    5e/pop-to-esi
    58/pop-to-eax
$write-stream:end:
    # . epilogue
    89/copy                         3/mod/direct    4/rm32/esp    .           .             .           5/r32/ebp   .               .                 # copy ebp to esp
    5d/pop-to-ebp
    c3/return

_write-stream:  # fd: int, s: (addr stream byte)
    # . prologue
    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
    # esi = s
    8b/copy                         1/mod/*+disp8   5/rm32/ebp    .           .             .           6/r32/esi   0xc/disp8       .                 # copy *(ebp+12) to esi
    # edi = s->read
    8b/copy                         1/mod/*+disp8   6/rm32/esi    .           .             .           7/r32/edi   4/disp8         .                 # copy *(esi+4) to edi
    # edx = s->write
    8b/copy                         0/mod/indirect  6/rm32/esi    .           .             .           2/r32/edx   .               .                 # copy *esi to edx
    # syscall_write(fd, &s->data[s->read], s->write - s->read)
    # . . fd: ebx
    8b/copy                         1/mod/*+disp8   5/rm32/ebp    .           .             .           3/r32/ebx   8/disp8         .                 # copy *(ebp+8) to ebx
    # . . data: ecx = &s->data[s->read]
    8d/copy-address                 1/mod/*+disp8   4/rm32/sib    6/base/esi  7/index/edi   .           1/r32/ecx   0xc/disp8       .                 # copy esi+edi+12 to ecx
    # . . size: edx = s->write - s->read
    29/subtract                     3/mod/direct    2/rm32/edx    .           .             .           7/r32/edi   .               .                 # subtract edi from edx
    # . . syscall
    e8/call  syscall_write/disp32
    # if (eax < 0) abort
    3d/compare-eax-with  0/imm32
    0f 8c/jump-if-<  $_write-stream:abort/disp32
    # s->read += eax
    01/add                          1/mod/*+disp8   6/rm32/esi    .           .             .           0/r32/eax   4/disp8         .                 # add eax to *(esi+4)
    # . 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
    # . epilogue
    89/copy                         3/mod/direct    4/rm32/esp    .           .             .           5/r32/ebp   .               .                 # copy ebp to esp
    5d/pop-to-ebp
    c3/return

$_write-stream:abort:
    # . _write(2/stderr, error)
    # . . push args
    68/push  "_write-stream: failed to write to file\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
    e8/call  syscall_exit/disp32
    # never gets here

test-write-stream-single:
    # setup
    # . clear-stream(_test-stream)
    # . . push args
    68/push  _test-stream/imm32
    # . . call
    e8/call  clear-stream/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               4/imm32           # add to esp
    # . clear-stream(_test-stream2)
    # . . push args
    68/push  _test-stream2/imm32
    # . . call
    e8/call  clear-stream/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               4/imm32           # add to esp
    # . write(_test-stream2, "Ab")
    # . . push args
    68/push  "Ab"/imm32
    68/push  _test-stream2/imm32
    # . . call
    e8/call  write/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
    # write-stream(_test-stream, _test-stream2)
    # . . push args
    68/push  _test-stream2/imm32
    68/push  _test-stream/imm32
    # . . call
    e8/call  write-stream/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
    # check-stream-equal(_test-stream, "Ab", msg)
    # . . push args
    68/push  "F - test-write-stream-single"/imm32
    68/push  "Ab"/imm32
    68/push  _test-stream/imm32
    # . . call
    e8/call  check-stream-equal/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               0xc/imm32         # add to esp
    # . end
    c3/return

test-write-stream-appends:
    # setup
    # . clear-stream(_test-stream)
    # . . push args
    68/push  _test-stream/imm32
    # . . call
    e8/call  clear-stream/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               4/imm32           # add to esp
    # . clear-stream(_test-stream2)
    # . . push args
    68/push  _test-stream2/imm32
    # . . call
    e8/call  clear-stream/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               4/imm32           # add to esp
    # . write(_test-stream2, "C")
    # . . push args
    68/push  "C"/imm32
    68/push  _test-stream2/imm32
    # . . call
    e8/call  write/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
    # first write
    # . write-stream(_test-stream, _test-stream2)
    # . . push args
    68/push  _test-stream2/imm32
    68/push  _test-stream/imm32
    # . . call
    e8/call  write-stream/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
    # second write
    # . write(_test-stream2, "D")
    # . . push args
    68/push  "D"/imm32
    68/push  _test-stream2/imm32
    # . . call
    e8/call  write/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
    # . write-stream(_test-stream, _test-stream2)
    # . . push args
    68/push  _test-stream2/imm32
    68/push  _test-stream/imm32
    # . . call
    e8/call  write-stream/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
    # check-stream-equal(_test-stream, "CD", msg)
    # . . push args
    68/push  "F - test-write-stream-appends"/imm32
    68/push  "CD"/imm32
    68/push  _test-stream/imm32
    # . . call
    e8/call  check-stream-equal/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               0xc/imm32         # add to esp
    # . end
    c3/return

== data

_test-stream2:  # (stream byte)
    # current write index
    4/imm32
    # current read index
    1/imm32
    # size
    8/imm32
    # data
    41/A 42/B 43/C 44/D 00 00 00 00  # 8 bytes

# . . vim:nowrap:textwidth=0