about summary refs log tree commit diff stats
path: root/309stream.subx
blob: 56b192728b5629f4ed1238fb9975f488f57975ba (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
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
# Some unsafe methods not intended to be used directly in SubX, only through
# Mu after proper type-checking.

== code

stream-empty?:  # s: (addr stream _) -> result/eax: boolean
    # . prologue
    55/push-ebp
    89/<- %ebp 4/r32/esp
    # . save registers
    51/push-ecx
    56/push-esi
    # result = false
    b8/copy-to-eax 0/imm32/false
    # esi = s
    8b/-> *(ebp+8) 6/r32/esi
    # return s->read >= s->write
    8b/-> *esi 1/r32/ecx
    39/compare-with *(esi+4) 1/r32/ecx
    0f 9d/set-if->= %al
$stream-empty?:end:
    # . restore registers
    5e/pop-to-esi
    59/pop-to-ecx
    # . epilogue
    89/<- %esp 5/r32/ebp
    5d/pop-to-ebp
    c3/return

stream-full?:  # s: (addr stream _) -> result/eax: boolean
    # . prologue
    55/push-ebp
    89/<- %ebp 4/r32/esp
    # . save registers
    51/push-ecx
    56/push-esi
    # result = false
    b8/copy-to-eax 0/imm32/false
    # esi = s
    8b/-> *(ebp+8) 6/r32/esi
    # return s->write >= s->size
    8b/-> *(esi+8) 1/r32/ecx
    39/compare-with *esi 1/r32/ecx
    0f 9d/set-if->= %al
$stream-full?:end:
    # . restore registers
    5e/pop-to-esi
    59/pop-to-ecx
    # . epilogue
    89/<- %esp 5/r32/ebp
    5d/pop-to-ebp
    c3/return

write-to-stream:  # s: (addr stream _), in: (addr byte), n: int
    # . prologue
    55/push-ebp
    89/<- %ebp 4/r32/esp
    # . save registers
    50/push-eax
    51/push-ecx
    52/push-edx
    53/push-ebx
    57/push-edi
    # edi = s
    8b/-> *(ebp+8) 7/r32/edi
    # var swrite/edx: int = s->write
    8b/-> *edi 2/r32/edx
    # if (swrite + n > s->size) abort
    8b/-> *(ebp+0x10) 1/r32/ecx
    01/add-to %ecx 2/r32/edx
    3b/compare 1/r32/ecx *(edi+8)
    0f 8f/jump-if-> $write-to-stream:abort/disp32
    # var out/edx: (addr byte) = s->data + s->write
    8d/copy-address *(edi+edx+0xc) 2/r32/edx
    # var outend/ebx: (addr byte) = out + n
    8b/-> *(ebp+0x10) 3/r32/ebx
    8d/copy-address *(edx+ebx) 3/r32/ebx
    # eax = in
    8b/-> *(ebp+0xc) 0/r32/eax
    # var inend/ecx: (addr byte) = in + n
    8b/-> *(ebp+0x10) 1/r32/ecx
    8d/copy-address *(eax+ecx) 1/r32/ecx
    #
    (_append-4  %edx %ebx  %eax %ecx)  # => eax
    # s->write += n
    8b/-> *(ebp+0x10) 1/r32/ecx
    01/add-to *edi 1/r32/ecx
$write-to-stream:end:
    # . restore registers
    5f/pop-to-edi
    5b/pop-to-ebx
    5a/pop-to-edx
    59/pop-to-ecx
    58/pop-to-eax
    # . epilogue
    89/<- %esp 5/r32/ebp
    5d/pop-to-ebp
    c3/return

$write-to-stream:abort:
    (draw-text-wrapping-right-then-down-from-cursor-over-full-screen 0 "write-to-stream: stream full" 3 0)  # 3=cyan
    {
      eb/jump loop/disp8
    }
    # never gets here

read-from-stream:  # s: (addr stream _), out: (addr byte), n: int
    # . prologue
    55/push-ebp
    89/<- %ebp 4/r32/esp
    # . save registers
    50/push-eax
    51/push-ecx
    52/push-edx
    53/push-ebx
    56/push-esi
    # esi = s
    8b/-> *(ebp+8) 6/r32/esi
    # var sread/edx: int = s->read
    8b/-> *(esi+4) 2/r32/edx
    # if (sread + n > s->write) abort
    8b/-> *(ebp+0x10) 1/r32/ecx
    01/add-to %ecx 2/r32/edx
    3b/compare 1/r32/ecx *esi
    0f 8f/jump-if-> $read-from-stream:abort/disp32
    # var in/edx: (addr byte) = s->data + s->read
    8d/copy-address *(esi+edx+0xc) 2/r32/edx
    # var inend/ebx: (addr byte) = in + n
    8b/-> *(ebp+0x10) 3/r32/ebx
    8d/copy-address *(edx+ebx) 3/r32/ebx
    # eax = out
    8b/-> *(ebp+0xc) 0/r32/eax
    # var outend/ecx: (addr byte) = out + n
    8b/-> *(ebp+0x10) 1/r32/ecx
    8d/copy-address *(eax+ecx) 1/r32/ecx
    #
    (_append-4  %eax %ecx  %edx %ebx)  # => eax
    # s->read += n
    8b/-> *(ebp+0x10) 1/r32/ecx
    01/add-to *(esi+4) 1/r32/ecx
$read-from-stream:end:
    # . restore registers
    5e/pop-to-esi
    5b/pop-to-ebx
    5a/pop-to-edx
    59/pop-to-ecx
    58/pop-to-eax
    # . epilogue
    89/<- %esp 5/r32/ebp
    5d/pop-to-ebp
    c3/return

$read-from-stream:abort:
    (draw-text-wrapping-right-then-down-from-cursor-over-full-screen 0 "read-from-stream: stream empty" 3 0)  # 3=cyan
    {
      eb/jump loop/disp8
    }
    # never gets here

stream-first:  # s: (addr stream byte) -> result/eax: byte
    # . prologue
    55/push-ebp
    89/<- %ebp 4/r32/esp
    # . save registers
    51/push-ecx
    56/push-esi
    # result = false
    b8/copy-to-eax 0/imm32
    # esi = s
    8b/-> *(ebp+8) 6/r32/esi
    # var idx/ecx: int = s->read
    8b/-> *(esi+4) 1/r32/ecx
    # if idx >= s->write return 0
    3b/compare-with 1/r32/ecx *esi
    7d/jump-if->= $stream-first:end/disp8
    # result = s->data[idx]
    8a/byte-> *(esi+ecx+0xc) 0/r32/AL
$stream-first:end:
    # . restore registers
    5e/pop-to-esi
    59/pop-to-ecx
    # . epilogue
    89/<- %esp 5/r32/ebp
    5d/pop-to-ebp
    c3/return

stream-final:  # s: (addr stream byte) -> result/eax: byte
    # . prologue
    55/push-ebp
    89/<- %ebp 4/r32/esp
    # . save registers
    51/push-ecx
    56/push-esi
    # result = false
    b8/copy-to-eax 0/imm32
    # esi = s
    8b/-> *(ebp+8) 6/r32/esi
    # var max/ecx: int = s->write
    8b/-> *esi 1/r32/ecx
    # if s->read >= max return 0
    39/compare-with *(esi+4) 1/r32/ecx
    7d/jump-if->= $stream-final:end/disp8
    # var idx/ecx: int = max - 1
    49/decrement-ecx
    # result = s->data[idx]
    8a/byte-> *(esi+ecx+0xc) 0/r32/AL
$stream-final:end:
    # . restore registers
    5e/pop-to-esi
    59/pop-to-ecx
    # . epilogue
    89/<- %esp 5/r32/ebp
    5d/pop-to-ebp
    c3/return