about summary refs log tree commit diff stats
path: root/cpp/.traces/get_address_indirect
diff options
context:
space:
mode:
authorKartik K. Agaram <vc@akkartik.com>2015-04-29 17:07:40 -0700
committerKartik K. Agaram <vc@akkartik.com>2015-04-29 17:07:40 -0700
commit0cc4f18dd56e2e6a80809d48ef1d1e0fb302029e (patch)
treeffe02c48e563bf88119805529a34e4a85be4d544 /cpp/.traces/get_address_indirect
parent9da019fcda10240cbce35b6b0b3e148d1219b4a4 (diff)
downloadmu-0cc4f18dd56e2e6a80809d48ef1d1e0fb302029e.tar.gz
1222
Diffstat (limited to 'cpp/.traces/get_address_indirect')
0 files changed, 0 insertions, 0 deletions
 

generated by cgit-pink 1.4.1-2-gfad0 (git 2.36.2.497.gbbea4dcf42) at 2024-07-08 14:18:48 +0000


 


='n111' href='#n111'>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


# Write out the (hex) textual representation of numbers.

== 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

# convert the lowest nibble of eax to ascii and return it in the lowest byte of eax
to-hex-char:  # in/eax: int -> out/eax: int
    # no error checking; accepts argument in eax
    # if (eax <= 9) return eax + '0'
    3d/compare-eax-with  0x9/imm32/9
    7f/jump-if->  $to-hex-char:else/disp8
    05/add-to-eax  0x30/imm32/0
    c3/return
$to-hex-char:else:
    # otherwise return eax + 'a' - 10
    05/add-to-eax  0x57/imm32/a-10
    c3/return

append-byte-hex:  # f: (addr stream byte), n: int
    # . prologue
    55/push-ebp
    89/copy                         3/mod/direct    5/rm32/ebp    .           .             .           4/r32/esp   .               .                 # copy esp to ebp
    # . save registers
    50/push-eax
    # AL = convert upper nibble to hex
    8b/copy                         1/mod/*+disp8   5/rm32/ebp    .           .             .           0/r32/eax   0xc/disp8       .                 # copy *(ebp+12) to eax
    c1/shift    5/subop/logic-right 3/mod/direct    0/rm32/eax    .           .             .           .           .               4/imm8            # shift eax right by 4 bits, while padding zeroes
    25/and-eax  0xf/imm32
    # . AL = to-hex-char(AL)
    e8/call  to-hex-char/disp32
    # append-byte(f, AL)
    # . . push args
    50/push-eax
    ff          6/subop/push        1/mod/*+disp8   5/rm32/ebp    .           .             .           .           8/disp8         .                 # push *(ebp+8)
    # . . call
    e8/call  append-byte/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
    # AL = convert lower nibble to hex
    8b/copy                         1/mod/*+disp8   5/rm32/ebp    .           .             .           0/r32/eax   0xc/disp8       .                 # copy *(ebp+12) to eax
    25/and-eax  0xf/imm32
    # . AL = to-hex-char(AL)
    e8/call  to-hex-char/disp32
    # append-byte(f, AL)
    # . . push args
    50/push-eax
    ff          6/subop/push        1/mod/*+disp8   5/rm32/ebp    .           .             .           .           8/disp8         .                 # push *(ebp+8)
    # . . call
    e8/call  append-byte/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
$append-byte-hex:end:
    # . restore registers
    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

test-append-byte-hex:
    # - check that append-byte-hex adds the hex textual representation
    # 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
    # append-byte-hex(_test-stream, 0xa)  # exercises digit, non-digit as well as leading zero
    # . . push args
    68/push  0xa/imm32
    68/push  _test-stream/imm32
    # . . call
    e8/call  append-byte-hex/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
    # check-stream-equal(_test-stream, "0a", msg)
    # . . push args
    68/push  "F - test-append-byte-hex"/imm32
    68/push  "0a"/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

write-int32-hex:  # f: (addr stream byte), n: int
    # . prologue
    55/push-ebp
    89/copy                         3/mod/direct    5/rm32/ebp    .           .             .           4/r32/esp   .               .                 # copy esp to ebp
$write-int32-hex:hex-prefix:
    # write(f, "0x")
    # . . push args
    68/push  "0x"/imm32
    ff          6/subop/push        1/mod/*+disp8   5/rm32/ebp    .           .             .           .           8/disp8         .                 # push *(ebp+8)
    # . . call
    e8/call  write/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
$write-int32-hex:rest:
    # write-int32-hex-bits(f, n, 32)
    # . . push args
    68/push  0x20/imm32
    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-int32-hex-bits/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               0xc/imm32         # add to esp
$write-int32-hex:end:
    # . epilogue
    89/copy                         3/mod/direct    4/rm32/esp    .           .             .           5/r32/ebp   .               .                 # copy ebp to esp
    5d/pop-to-ebp
    c3/return

# print rightmost 'bits' of 'n'
# bits must be multiple of 4
write-int32-hex-bits:  # f: (addr stream byte), n: int, bits: int
    # pseudocode:
    #  bits -= 4
    #  while true
    #    if (bits < 0) break
    #    eax = n >> bits
    #    eax = eax & 0xf
    #    append-byte(f, AL)
    #    bits -= 4
    #
    # . 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
    # ecx = bits-4
    8b/copy                         1/mod/*+disp8   5/rm32/ebp    .           .             .           1/r32/ecx   0x10/disp8      .                 # copy *(ebp+16) to ecx
    81          5/subop/subtract    3/mod/direct    1/rm32/ecx    .           .             .           .           .               4/imm32           # subtract from ecx
$write-int32-hex-bits:loop:
    # if (bits < 0) break
    81          7/subop/compare     3/mod/direct    1/rm32/ecx    .           .             .           .           .               0/imm32           # compare ecx
    7c/jump-if-<  $write-int32-hex-bits:end/disp8
    # eax = n >> bits
    8b/copy                         1/mod/*+disp8   5/rm32/ebp    .           .             .           0/r32/eax   0xc/disp8       .                 # copy *(ebp+12) to eax
    d3/>>ecx    5/subop/pad-zeroes  3/mod/direct    0/rm32/eax    .           .             .           .           .               .                 # shift eax right by ecx bits, padding zeroes
    # eax = to-hex-char(AL)
    25/and-eax  0xf/imm32
    e8/call  to-hex-char/disp32
    # append-byte(f, AL)
    # . . push args
    50/push-eax
    ff          6/subop/push        1/mod/*+disp8   5/rm32/ebp    .           .             .           .           8/disp8         .                 # push *(ebp+8)
    # . . call
    e8/call  append-byte/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
    # bits -= 4
    81          5/subop/subtract    3/mod/direct    1/rm32/ecx    .           .             .           .           .               4/imm32           # subtract from ecx
    eb/jump  $write-int32-hex-bits:loop/disp8
$write-int32-hex-bits:end:
    # . restore registers
    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

test-write-int32-hex:
    # - check that write-int32-hex prints the hex textual representation
    # 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
    # write-int32-hex(_test-stream, 0x8899aa)
    # . . push args
    68/push  0x8899aa/imm32
    68/push  _test-stream/imm32
    # . . call
    e8/call  write-int32-hex/disp32
    # . . discard args
    81          0/subop/add         3/mod/direct    4/rm32/esp    .           .             .           .           .               8/imm32           # add to esp
    # check-stream-equal(_test-stream, "0x008899aa", msg)
    # . . push args
    68/push  "F - test-write-int32-hex"/imm32
    68/push  "0x008899aa"/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

# . . vim:nowrap:textwidth=0