1 /* code.c
2
3 Routines for handling Flash2 AVM2 ABC Actionscript
4
5 Extension module for the rfxswf library.
6 Part of the swftools package.
7
8 Copyright (c) 2008 Matthias Kramm <kramm@quiss.org>
9
10 This program is free software; you can redistribute it and/or modify
11 it under the terms of the GNU General Public License as published by
12 the Free Software Foundation; either version 2 of the License, or
13 (at your option) any later version.
14
15 This program is distributed in the hope that it will be useful,
16 but WITHOUT ANY WARRANTY; without even the implied warranty of
17 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 GNU General Public License for more details.
19
20 You should have received a copy of the GNU General Public License
21 along with this program; if not, write to the Free Software
22 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */
23
24 #include <assert.h>
25 #include "code.h"
26 #include "pool.h"
27
28 #define OP_REGISTER 1
29 #define OP_STACK_ARGS 2
30 #define OP_STACK_NS 4
31 #define OP_SET_DXNS 8
32 #define OP_RETURN 16
33 #define OP_THROW 32
34 #define OP_BRANCH 64
35 #define OP_JUMP 128
36 #define OP_LABEL 256
37 #define OP_LOOKUPSWITCH 512
38 #define OP_NEED_ACTIVATION 1024
39 #define OP_STACK_ARGS2 2048
40 #define OP_INTERNAL 32768
41
42 /* 2 = u30 index into multiname
43 m = u30 index into method
44 n = u30 number of params
45 i = u30 index into method info
46 b = byte
47 c = u30 index into class
48 N = u30 index into namespaces
49 s = string (u30 index into strings)
50 S = switch
51 u = u30
52 r = register
53 */
54
55 opcode_t opcodes[]={
56 {0xa0, "add", "", -2, 1, 0, 0},
57 {0xc5, "add_i", "", -2, 1, 0, 0},
58 {0x86, "astype", "2", -1, 1, 0, 0},
59 {0x87, "astypelate", "", -2, 1, 0, 0},
60 {0xA8, "bitand", "", -2, 1, 0, 0},
61 {0x97, "bitnot", "", -1, 1, 0, 0},
62 {0xa9, "bitor", "", -2, 1, 0, 0},
63 {0xaa, "bitxor", "", -2, 1, 0, 0},
64 {0x41, "call", "n", -2, 1, 0, OP_STACK_ARGS},
65 {0x43, "callmethod", "mn", -1, 1, 0, OP_STACK_ARGS},
66 {0x4c, "callproplex", "2n", -1, 1, 0, OP_STACK_ARGS|OP_STACK_NS},
67 {0x46, "callproperty", "2n", -1, 1, 0, OP_STACK_ARGS|OP_STACK_NS},
68 {0x4f, "callpropvoid", "2n", -1, 0, 0, OP_STACK_ARGS|OP_STACK_NS},
69 {0x44, "callstatic", "in", -1, 1, 0, OP_STACK_ARGS},
70 {0x45, "callsuper", "2n", -1, 1, 0, OP_STACK_ARGS|OP_STACK_NS},
71 {0x4e, "callsupervoid", "2n", -1, 0, 0, OP_STACK_ARGS|OP_STACK_NS},
72 {0x78, "checkfilter", "", -1, 1, 0, 0},
73 {0x80, "coerce", "2", -1, 1, 0, 0},
74 {0x82, "coerce_a", "", -1, 1, 0, 0},
75 {0x85, "coerce_s", "", -1, 1, 0, 0},
76 {0x42, "construct", "n", -1, 1, 0, OP_STACK_ARGS},
77 {0x4a, "constructprop", "2n", -1, 1, 0, OP_STACK_ARGS|OP_STACK_NS},
78 {0x49, "constructsuper", "n", -1, 0, 0, OP_STACK_ARGS},
79 {0x76, "convert_b", "", -1, 1, 0, 0},
80 {0x73, "convert_i", "", -1, 1, 0, 0},
81 {0x75, "convert_d", "", -1, 1, 0, 0},
82 {0x77, "convert_o", "", -1, 1, 0, 0},
83 {0x74, "convert_u", "", -1, 1, 0, 0},
84 {0x70, "convert_s", "", -1, 1, 0, 0},
85 {0xef, "debug", "D", 0, 0, 0, 0},
86 {0xf1, "debugfile", "s", 0, 0, 0, 0},
87 {0xf0, "debugline", "u", 0, 0, 0, 0},
88 {0x94, "declocal", "r", 0, 0, 0, OP_REGISTER},
89 {0xc3, "declocal_i", "r", 0, 0, 0, OP_REGISTER},
90 {0x93, "decrement", "", -1, 1, 0, 0},
91 {0xc1, "decrement_i", "", -1, 1, 0, 0},
92 {0x6a, "deleteproperty", "2", -1, 1, 0, OP_STACK_NS},
93 {0xa3, "divide", "", -2, 1, 0, 0},
94 {0x2a, "dup", "", -1, 2, 0, 0},
95 {0x06, "dxns", "s", 0, 0, 0, OP_SET_DXNS},
96 {0x07, "dxnslate", "", -1, 0, 0, OP_SET_DXNS},
97 {0xab, "equals", "", -2, 1, 0, 0},
98 {0x72, "esc_xattr", "", -1, 1, 0, 0},
99 {0x71, "esc_xelem", "", -1, 1, 0, 0},
100 {0x5e, "findproperty", "2", 0, 1, 0, OP_STACK_NS},
101 {0x5d, "findpropstrict", "2", 0, 1, 0, OP_STACK_NS},
102 {0x59, "getdescendants", "2", -1, 1, 0, OP_STACK_NS},
103 {0x64, "getglobalscope", "", 0, 1, 0, 0},
104 {0x6e, "getglobalslot", "u", 0, 1, 0, 0},
105 {0x60, "getlex", "2", 0, 1, 0, 0}, //multiname may not be runtime
106 {0x62, "getlocal", "r", 0, 1, 0, OP_REGISTER},
107 {0xd0, "getlocal_0", "", 0, 1, 0, OP_REGISTER},
108 {0xd1, "getlocal_1", "", 0, 1, 0, OP_REGISTER},
109 {0xd2, "getlocal_2", "", 0, 1, 0, OP_REGISTER},
110 {0xd3, "getlocal_3", "", 0, 1, 0, OP_REGISTER},
111 {0x66, "getproperty", "2", -1, 1, 0, OP_STACK_NS},
112 {0x65, "getscopeobject", "u", 0, 1, 0, 0}, // u = index into scope stack
113 {0x6c, "getslot", "u", -1, 1, 0, 0},
114 {0x04, "getsuper", "2", -1, 1, 0, OP_STACK_NS},
115 {0xaf, "greaterthan", "", -2, 1, 0, 0},
116 {0xb0, "greaterequals", "", -2, 1, 0, 0},
117 {0x1f, "hasnext", "", -2, 1, 0, 0},
118 {0x32, "hasnext2", "rr", 0, 1, 0, OP_REGISTER},
119 {0x13, "ifeq", "j", -2, 0, 0, OP_BRANCH},
120 {0x12, "iffalse", "j", -1, 0, 0, OP_BRANCH},
121 {0x18, "ifge", "j", -2, 0, 0, OP_BRANCH},
122 {0x17, "ifgt", "j", -2, 0, 0, OP_BRANCH},
123 {0x16, "ifle", "j", -2, 0, 0, OP_BRANCH},
124 {0x15, "iflt", "j", -2, 0, 0, OP_BRANCH},
125 {0x0f, "ifnge", "j", -2, 0, 0, OP_BRANCH},
126 {0x0e, "ifngt", "j", -2, 0, 0, OP_BRANCH},
127 {0x0d, "ifnle", "j", -2, 0, 0, OP_BRANCH},
128 {0x0c, "ifnlt", "j", -2, 0, 0, OP_BRANCH},
129 {0x14, "ifne", "j", -2, 0, 0, OP_BRANCH},
130 {0x19, "ifstricteq", "j", -2, 0, 0, OP_BRANCH},
131 {0x1a, "ifstrictne", "j", -2, 0, 0, OP_BRANCH},
132 {0x11, "iftrue", "j", -1, 0, 0, OP_BRANCH},
133 {0xb4, "in", "", -2, 1, 0, 0},
134 {0x92, "inclocal", "r", 0, 0, 0, OP_REGISTER},
135 {0xc2, "inclocal_i", "r", 0, 0, 0, OP_REGISTER},
136 {0x91, "increment", "", -1, 1, 0, 0},
137 {0xc0, "increment_i", "", -1, 1, 0, 0},
138 {0x68, "initproperty", "2", -2, 0, 0, OP_STACK_NS},
139 {0xb1, "instanceof", "", -2, 1, 0, 0},
140 {0xb2, "istype", "2", -1, 1, 0, 0}, // may not be a runtime multiname
141 {0xb3, "istypelate", "", -2, 1, 0, 0},
142 {0x10, "jump", "j", 0, 0, 0, OP_JUMP},
143 {0x08, "kill", "r", 0, 0, 0, OP_REGISTER},
144 {0x09, "label", "", 0, 0, 0, OP_LABEL},
145 {0xae, "lessequals", "", -2, 1, 0, 0},
146 {0xad, "lessthan", "", -2, 1, 0, 0},
147 {0x1b, "lookupswitch", "S", -1, 0, 0, OP_LOOKUPSWITCH},
148 {0xa5, "lshift", "", -2, 1, 0, 0},
149 {0xa4, "modulo", "", -2, 1, 0, 0},
150 {0xa2, "multiply", "", -2, 1, 0, 0},
151 {0xc7, "multiply_i", "", -2, 1, 0, 0},
152 {0x90, "negate", "", -1, 1, 0, 0},
153 {0xc4, "negate_i", "", -1, 1, 0, 0},
154 {0x57, "newactivation", "", 0, 1, 0, OP_NEED_ACTIVATION},
155 {0x56, "newarray", "n", 0, 1, 0, OP_STACK_ARGS},
156 {0x5a, "newcatch", "u", 0, 1, 0, 0}, //u = index into exception_info
157 {0x58, "newclass", "c", -1, 1, 0, 0}, //c = index into class_info
158 {0x40, "newfunction", "m", 0, 1, 0, 0}, //i = index into method_info
159 {0x55, "newobject", "n", 0, 1, 0, OP_STACK_ARGS2},
160 {0x1e, "nextname", "", -2, 1, 0, 0},
161 {0x23, "nextvalue", "", -2, 1, 0, 0},
162 {0x02, "nop", "", 0, 0, 0, 0},
163 {0x96, "not", "", -1, 1, 0 ,0},
164 {0x29, "pop", "", -1, 0, 0, 0},
165 {0x1d, "popscope", "", 0, 0,-1, 0},
166 {0x24, "pushbyte", "b", 0, 1, 0, 0},
167 {0x2f, "pushdouble", "f", 0, 1, 0, 0}, //index into floats
168 {0x27, "pushfalse", "", 0, 1, 0, 0},
169 {0x2d, "pushint", "I", 0, 1, 0, 0}, //index into ints
170 {0x31, "pushnamespace", "N", 0, 1, 0, 0}, //index into namespace
171 {0x28, "pushnan", "", 0, 1, 0, 0},
172 {0x20, "pushnull", "", 0, 1, 0, 0},
173 {0x30, "pushscope", "", -1, 0, 1, 0},
174 {0x25, "pushshort", "u", 0, 1, 0, 0},
175 {0x2c, "pushstring", "s", 0, 1, 0, 0},
176 {0x26, "pushtrue", "", 0, 1, 0, 0},
177 {0x2e, "pushuint", "U", 0, 1, 0, 0}, //index into uints
178 {0x21, "pushundefined", "", 0, 1, 0, 0},
179 {0x1c, "pushwith", "", -1, 0, 1, 0},
180 {0x48, "returnvalue", "", -1, 0, 0, OP_RETURN},
181 {0x47, "returnvoid", "", 0, 0, 0, OP_RETURN},
182 {0xa6, "rshift", "", -2, 1, 0, 0},
183 {0x63, "setlocal", "r", -1, 0, 0, OP_REGISTER},
184 {0xd4, "setlocal_0", "", -1, 0, 0, OP_REGISTER},
185 {0xd5, "setlocal_1", "", -1, 0, 0, OP_REGISTER},
186 {0xd6, "setlocal_2", "", -1, 0, 0, OP_REGISTER},
187 {0xd7, "setlocal_3", "", -1, 0, 0, OP_REGISTER},
188 {0x6f, "setglobalslot", "u", -1, 0, 0, 0},
189 {0x61, "setproperty", "2", -2, 0, 0, OP_STACK_NS},
190 {0x6d, "setslot", "u", -2, 0, 0, 0},
191 {0x05, "setsuper", "2", -2, 0, 0, OP_STACK_NS},
192 {0xac, "strictequals", "", -2, 1, 0, 0},
193 {0xa1, "subtract", "", -2, 1, 0, 0},
194 {0xc6, "subtract_i", "", -2, 1, 0, 0},
195 {0x2b, "swap", "", -2, 2, 0, 0},
196 {0x03, "throw", "", -1, 0, 0, OP_THROW},
197 {0x95, "typeof", "", -1, 1, 0, 0},
198 {0xa7, "urshift", "", -2, 1, 0, 0},
199
200 /* Alchemy opcodes */
201 {0x3a, "si8", "", -2, 0, 0, 0},
202 {0x3b, "si16", "", -2, 0, 0, 0},
203 {0x3c, "si32", "", -2, 0, 0, 0},
204 {0x3d, "sf32", "", -2, 0, 0, 0},
205 {0x3e, "sf64", "", -2, 0, 0, 0},
206 {0x35, "li8", "", -1, 1, 0, 0},
207 {0x36, "li16", "", -1, 1, 0, 0},
208 {0x37, "li32", "", -1, 1, 0, 0},
209 {0x38, "lf32", "", -1, 1, 0, 0},
210 {0x39, "lf64", "", -1, 1, 0, 0},
211 {0x50, "sxi1", "", -1, 1, 0, 0},
212 {0x51, "sxi8", "", -1, 1, 0, 0},
213 {0x52, "sxi16", "", -1, 1, 0, 0},
214
215 /* opcodes not documented, but seen in the wild */
216 {0x53, "applytype", "n", -1, 1, 0, OP_STACK_ARGS}, //seen in builtin.abc
217
218 /* dummy instructions. Warning: these are not actually supported by flash */
219 {0xfb, "__pushpackage__", "s", 0, 1, 0, OP_INTERNAL},
220 {0xfc, "__rethrow__", "", 0, 0, 0, OP_THROW|OP_INTERNAL},
221 {0xfd, "__fallthrough__", "s", 0, 0, 0, OP_INTERNAL},
222 {0xfe, "__continue__", "s", 0, 0, 0, OP_RETURN|OP_INTERNAL},
223 {0xff, "__break__", "s", 0, 0, 0, OP_RETURN|OP_INTERNAL},
224 };
225
226 static opcode_t* op2op[256] = {0,0,0};
227
opcode_get(U8 op)228 static inline opcode_t* opcode_get(U8 op)
229 {
230 int t;
231 if(!op2op[0x02]) {
232 memset(op2op, 0, sizeof(op2op));
233 for(t=0;t<sizeof(opcodes)/sizeof(opcodes[0]);t++) {
234 op2op[opcodes[t].opcode] = &opcodes[t];
235 }
236 }
237 return op2op[op];
238 }
239
pos2code(code_t ** bytepos,code_t * c,int pos,int len)240 static code_t*pos2code(code_t**bytepos, code_t*c, int pos, int len)
241 {
242 if(c) {
243 pos+=c->pos;
244 }
245 if(pos < 0 ||
246 pos > len ||
247 (pos!=len && !bytepos[pos])) {
248 /* flex likes to generate these. yuck. */
249 if(c) {
250 opcode_t*op = opcode_get(c->opcode);
251 fprintf(stderr, "Warning: Invalid jump instruction \"%s\" from %d to %d (%d)\n", op->name, c->pos, pos, len);
252 } else {
253 fprintf(stderr, "Warning: Invalid jump to %d (%d)\n", pos, len);
254 }
255 return 0;
256 } else {
257 if(pos==len) {
258 //opcode_t*op = opcode_get(c->opcode);
259 //fprintf(stderr, "Warning: jump beyond end of code in instruction %s at position %d\n", op->name, c->pos);
260 return 0;
261 } else {
262 return bytepos[pos];
263 }
264 }
265 }
code_atposition(codelookup_t * l,int pos)266 code_t* code_atposition(codelookup_t*l, int pos)
267 {
268 return pos2code(l->bytepos, 0, pos, l->len);
269 }
270
lookupswitch_print(lookupswitch_t * l)271 void lookupswitch_print(lookupswitch_t*l)
272 {
273 printf("default: %p\n", l->def);
274 code_list_t*t = l->targets;
275 while(t) {
276 printf("target: %p\n", t->code);
277 t = t->next;
278 }
279 }
280
code_parse(TAG * tag,int len,abc_file_t * file,pool_t * pool,codelookup_t ** codelookup)281 code_t*code_parse(TAG*tag, int len, abc_file_t*file, pool_t*pool, codelookup_t**codelookup)
282 {
283 code_t*head=0;
284 code_t*code=0;
285 int start=tag->pos;
286 int end=tag->pos+len;
287 //printf("-->\n");fflush(stdout);
288
289 code_t**bytepos = rfx_calloc(sizeof(code_t*)*len);
290
291 while(tag->pos<end) {
292 int codepos = tag->pos-start;
293 U8 opcode = swf_GetU8(tag);
294 opcode_t*op = opcode_get(opcode);
295 if(!op) {
296 fprintf(stderr, "Can't parse opcode %02x\n", opcode);
297 continue;
298 }
299 //printf("%s\n", op->name);fflush(stdout);
300 NEW(code_t,c);
301 c->pos = codepos;
302
303 bytepos[codepos] = c;
304
305 if(!head) {
306 head = code = c;
307 } else {
308 code->next = c;
309 c->prev = code;
310 code = c;
311 }
312
313 c->opcode = opcode;
314
315 char*p = op->params;
316 int pos = 0;
317 while(*p) {
318 void*data = 0;
319 if(*p == 'n') { // number
320 data = (void*)(ptroff_t)swf_GetU30(tag);
321 } else if(*p == '2') { //multiname
322 data = multiname_clone(pool_lookup_multiname(pool, swf_GetU30(tag)));
323 } else if(*p == 'N') { //namespace
324 data = namespace_clone(pool_lookup_namespace(pool, swf_GetU30(tag)));
325 } else if(*p == 'U') { //uint
326 data = (void*)(ptroff_t)pool_lookup_uint(pool, swf_GetU30(tag));
327 } else if(*p == 'I') { //int
328 data = (void*)(ptroff_t)pool_lookup_int(pool, swf_GetU30(tag));
329 } else if(*p == 'f') { //int
330 double*fp = malloc(sizeof(double));
331 *fp = pool_lookup_float(pool, swf_GetU30(tag));
332 data = fp;
333 } else if(*p == 'm') { //method
334 data = array_getvalue(file->methods, swf_GetU30(tag));
335 } else if(*p == 'c') { //classinfo
336 data = array_getvalue(file->classes, swf_GetU30(tag));
337 } else if(*p == 'i') {
338 data = array_getvalue(file->method_bodies, swf_GetU30(tag));
339 } else if(*p == 'u') { // generic integer
340 data = (void*)(ptroff_t)swf_GetU30(tag);
341 } else if(*p == 'r') { // local register
342 data = (void*)(ptroff_t)swf_GetU30(tag);
343 } else if(*p == 'b') { // byte
344 data = (void*)(ptroff_t)swf_GetU8(tag);
345 } else if(*p == 'j') { // jump
346 int j = swf_GetS24(tag);
347 data = (void*)(ptroff_t)j;
348 } else if(*p == 's') { // string
349 string_t s = pool_lookup_string2(pool, swf_GetU30(tag));
350 data = string_dup3(&s);
351 } else if(*p == 'D') { // debug
352 /*type, usually 1*/
353 U8 type = swf_GetU8(tag);
354 if(type!=1)
355 fprintf(stderr, "Unknown debug type: %02x\n", type);
356 /*register name*/
357 code->data[0] = strdup((char*)pool_lookup_string(pool, swf_GetU30(tag)));
358 /*register index*/
359 code->data[1] = (void*)(ptroff_t)swf_GetU8(tag);
360 /*unused*/
361 swf_GetU30(tag);
362 } else if(*p == 'S') { // switch statement
363 lookupswitch_t*l = malloc(sizeof(lookupswitch_t));
364 l->def = (code_t*)(ptroff_t)swf_GetS24(tag);
365 l->targets = list_new();
366 int num = swf_GetU30(tag)+1;
367 int t;
368 for(t=0;t<num;t++)
369 list_append(l->targets, (code_t*)(ptroff_t)swf_GetS24(tag));
370 data = l;
371 } else {
372 printf("Can't parse opcode param type \"%c\" (for op %02x %s).\n", *p, code->opcode, op->name);
373 return 0;
374 }
375 code->data[pos++] = data;
376 p++;
377 }
378 }
379
380 //#define DEBUG_BYTES
381 #ifdef DEBUG_BYTES
382 int t;
383 for(t=0;t<len;t++) {
384 code_t*c = bytepos[t];
385 if(c) {
386 opcode_t*op = opcode_get(c->opcode);
387 if(op->flags & (OP_JUMP|OP_BRANCH)) {
388 printf("%50d) %02x %s %d\n", t, tag->data[start+t], op->name, c->data[0]);
389 } else {
390 printf("%50d) %02x %s\n", t, tag->data[start+t], op->name);
391 }
392 } else {
393 printf("%50d) %02x\n", t, tag->data[start+t]);
394 }
395 }
396 //printf("%05d) %02x\n", t, tag->data[start+t]);
397 #endif
398
399 code_t*c = head;
400 while(c) {
401 opcode_t*op = opcode_get(c->opcode);
402 if(op->flags & (OP_JUMP|OP_BRANCH)) {
403 int j = ((int)(ptroff_t)c->data[0]);
404 c->branch = pos2code(bytepos,c,j+4,len);
405 } else if(op->flags & (OP_LOOKUPSWITCH)) {
406 lookupswitch_t*l = (lookupswitch_t*)c->data[0];
407 int offset = 0;
408 l->def = pos2code(bytepos,c,(ptroff_t)l->def+offset,len);
409 code_list_t*t=l->targets;
410 while(t) {
411 t->code = pos2code(bytepos,c,(ptroff_t)t->code+offset,len);
412 t = t->next;
413 }
414 }
415 c = c->next;
416 }
417
418 if(codelookup) {
419 (*codelookup) = malloc(sizeof(codelookup_t));
420 (*codelookup)->bytepos = bytepos;
421 (*codelookup)->len = len;
422 } else {
423 free(bytepos);
424 }
425
426 return head;
427 }
428
codelookup_free(codelookup_t * codelookup)429 void codelookup_free(codelookup_t*codelookup)
430 {
431 free(codelookup->bytepos);codelookup->bytepos=0;
432 free(codelookup);
433 }
434
code_free(code_t * c)435 void code_free(code_t*c)
436 {
437 c = code_start(c);
438 while(c) {
439 code_t*next = c->next;
440 opcode_t*op = opcode_get(c->opcode);
441 char*p = op?op->params:"";
442 int pos=0;
443 while(*p) {
444 void*data = c->data[pos];
445 if(*p == '2') { //multiname
446 multiname_destroy(data);
447 } else if(*p == 'N') { //namespace
448 namespace_destroy(data);
449 } else if(strchr("sDf", *p)) {
450 free(data);
451 } else if(strchr("S", *p)) {
452 lookupswitch_t*l = (lookupswitch_t*)data;
453 list_free(l->targets);l->targets=0;
454 free(l);
455 }
456 c->data[pos]=0;
457 p++;pos++;
458 }
459 memset(c, 0, sizeof(c));
460 free(c);
461 c = next;
462 }
463 }
464
opcode_write(TAG * tag,code_t * c,pool_t * pool,abc_file_t * file,int length)465 static int opcode_write(TAG*tag, code_t*c, pool_t*pool, abc_file_t*file, int length)
466 {
467 opcode_t*op = opcode_get(c->opcode);
468 char*p = op->params;
469 int pos = 0;
470 int len = 0;
471
472 if(tag)
473 swf_SetU8(tag, c->opcode);
474 len++;
475
476 if(op->flags & OP_INTERNAL) {
477 if(c->opcode == OPCODE___BREAK__ ||
478 c->opcode == OPCODE___CONTINUE__) {
479 fprintf(stderr, "Unresolved %s\n", op->name);
480 } else {
481 fprintf(stderr, "Error: writing undefined internal opcode %s\n", op->name);
482 }
483 }
484
485 while(*p) {
486 void*data = c->data[pos++];
487 assert(pos<=2);
488 switch(*p) {
489 case 'n': { // number
490 len += swf_SetU30(tag, (ptroff_t)data);
491 break;
492 }
493 case '2': { //multiname
494 multiname_t*m = (multiname_t*)data;
495 len += swf_SetU30(tag, pool_register_multiname(pool, m));
496 break;
497 }
498 case 'N': { //namespace
499 namespace_t*ns = (namespace_t*)data;
500 len += swf_SetU30(tag, pool_register_namespace(pool, ns));
501 break;
502 }
503 case 'm': { //method
504 abc_method_t*m = (abc_method_t*)data;
505 len += swf_SetU30(tag, m->index);
506 break;
507 }
508 case 'c': { //classinfo
509 abc_class_t*cls = (abc_class_t*)data;
510 len += swf_SetU30(tag, cls->index);
511 break;
512 }
513 case 'i': { //methodbody
514 abc_method_body_t*m = (abc_method_body_t*)data;
515 len += swf_SetU30(tag, m->index);
516 break;
517 }
518 case 'I': { // int
519 len += swf_SetU30(tag, pool_register_int(pool, (ptroff_t)data));
520 break;
521 }
522 case 'U': { // uint
523 len += swf_SetU30(tag, pool_register_uint(pool, (ptroff_t)data));
524 break;
525 }
526 case 'f': { // float
527 len += swf_SetU30(tag, pool_register_float(pool, *(double*)data));
528 break;
529 }
530 case 'u': { // integer
531 len += swf_SetU30(tag, (ptroff_t)data);
532 break;
533 }
534 case 'r': { // integer
535 len += swf_SetU30(tag, (ptroff_t)data);
536 break;
537 }
538 case 'b': { // byte
539 if(tag)
540 swf_SetU8(tag, (ptroff_t)data);
541 len++;
542 break;
543 }
544 case 'j': { // jump
545 int skip = length-c->pos-4;
546 if(c->branch)
547 skip = (c->branch->pos) - c->pos - 4;
548 len += swf_SetS24(tag, skip);
549 break;
550 }
551 case 's': { // string
552 int index = pool_register_string2(pool, (string_t*)data);
553 len += swf_SetU30(tag, index);
554 break;
555 }
556 case 'D': { // debug statement
557 if(tag)
558 swf_SetU8(tag, 1);
559 len++;
560 len+=swf_SetU30(tag, pool_register_string(pool,c->data[0]));
561 if(tag)
562 swf_SetU8(tag, (ptroff_t)c->data[1]);
563 len++;
564 len+=swf_SetU30(tag, 0);
565 break;
566 }
567 case 'S': { // switch statement
568 lookupswitch_t*l = (lookupswitch_t*)data;
569 int offset = 0;
570 len+=swf_SetS24(tag, l->def->pos-c->pos+offset); //default
571 code_list_t*t = l->targets;
572 if(list_length(t)) {
573 len+=swf_SetU30(tag, list_length(t)-1); //nr-1
574 code_list_t*t = l->targets;
575 while(t) {
576 len+=swf_SetS24(tag, t->code->pos - c->pos+offset);
577 t = t->next;
578 }
579 } else {
580 len+=swf_SetU30(tag, 0); //nr-1
581 len+=swf_SetS24(tag, l->def->pos-c->pos+offset);
582 }
583 break;
584 }
585 default:
586 printf("Can't parse opcode param type \"%c\"\n", *p);
587 }
588 p++;
589 }
590 return len;
591 }
592
code_write(TAG * tag,code_t * code,pool_t * pool,abc_file_t * file)593 void code_write(TAG*tag, code_t*code, pool_t*pool, abc_file_t*file)
594 {
595 code = code_start(code);
596 int pos = 0;
597 int length = 0;
598 code_t*c = code;
599 while(c) {
600 c->pos = pos;
601 pos += opcode_write(0, c, pool, file, 0);
602 c = c->next;
603 }
604 length = pos;
605 swf_SetU30(tag, pos);
606 int start = tag->len;
607 c = code;
608 pos = 0;
609 while(c) {
610 opcode_t*op = opcode_get(code->opcode);
611 if(op->flags&(OP_BRANCH|OP_JUMP)) {
612 int skip = 0;
613 }
614 pos += opcode_write(tag, c, pool, file, length);
615 c = c->next;
616 }
617 assert(tag->len - start == pos);
618 }
619
620 typedef struct {
621 int stackpos;
622 int scopepos;
623 code_t*code;
624 char flags;
625 char error;
626 } stackpos_t;
627
628 typedef struct {
629 stackpos_t*stack;
630 int num;
631 int maxlocal;
632 int maxstack;
633 int maxscope;
634 int flags;
635 } currentstats_t;
636
stack_minus(code_t * c)637 static int stack_minus(code_t*c)
638 {
639 opcode_t*op = opcode_get(c->opcode);
640 if(op->stack_minus>0) {
641 fprintf(stderr, "Invalid opcode entry %02x %s\n", c->opcode, op->name);
642 }
643 int stack = op->stack_minus;
644 if(op->flags&OP_STACK_NS) {
645 multiname_t*m = (multiname_t*)c->data[0];
646 if(multiname_late_namespace(m))
647 stack--;
648 if(multiname_late_name(m))
649 stack--;
650 }
651 if(op->flags&OP_STACK_ARGS || op->flags&OP_STACK_ARGS2) {
652 assert(strchr(op->params, 'n'));
653 int nr = (ptroff_t)(op->params[0]=='n'?c->data[0]:c->data[1]);
654 stack-=nr;
655 if(op->flags&OP_STACK_ARGS2)
656 stack-=nr;
657 }
658 return stack;
659 }
handleregister(currentstats_t * stats,int reg)660 static void handleregister(currentstats_t*stats, int reg)
661 {
662 if(reg+1 > stats->maxlocal)
663 stats->maxlocal = reg+1;
664 }
665
666 #define FLAG_SEEN 1
667 #define FLAG_ERROR 2
668
dumpstack(currentstats_t * stats)669 static void dumpstack(currentstats_t*stats)
670 {
671 int t;
672 for(t=0;t<stats->num;t++) {
673 code_t*c = stats->stack[t].code;
674 opcode_t*op = opcode_get(c->opcode);
675 printf("%05d) %c %d:%d %s", t, (stats->stack[t].flags&FLAG_SEEN)?'x':'|',
676 stats->stack[t].stackpos,
677 stats->stack[t].scopepos,
678 op->name);
679
680 if(op->flags&(OP_BRANCH|OP_JUMP)) {
681 if(c->branch)
682 printf(" ->%d\n", c->branch->pos);
683 else
684 printf(" 00000000\n");
685 }
686 if(op->params[0]=='2') {
687 printf(" %s", multiname_tostring(c->data[0]));
688 } else if(op->params[0]=='N') {
689 printf(" %s", namespace_tostring(c->data[0]));
690 }
691 printf("\n");
692 }
693 }
694
callcode(currentstats_t * stats,int pos,int stack,int scope)695 static char callcode(currentstats_t*stats, int pos, int stack, int scope)
696 {
697 while(pos<stats->num) {
698 if(stats->stack[pos].flags&FLAG_SEEN) {
699 if(stats->stack[pos].stackpos != stack ||
700 stats->stack[pos].scopepos != scope) {
701 //dumpstack(stats);
702 stats->stack[pos].flags |= FLAG_ERROR;
703 fprintf(stderr, "Stack mismatch at pos %d\n", pos);
704 fprintf(stderr, "Should be: %d:%d, is: %d:%d\n", stack, scope,
705 stats->stack[pos].stackpos, stats->stack[pos].scopepos);
706
707 /* return error here if we do verification */
708 //return 0;
709 }
710 return 1;
711 }
712
713 stats->stack[pos].flags |= FLAG_SEEN;
714 stats->stack[pos].stackpos = stack;
715 stats->stack[pos].scopepos = scope;
716
717 code_t*c = stats->stack[pos].code;
718 opcode_t*op = opcode_get(c->opcode);
719
720 //printf("Walking %s at position %d, stack=%d, scope=%d\n", op->name, pos, stack, scope);
721
722 stack += stack_minus(c);
723
724 if(stack<0) {
725 stats->stack[pos].flags |= FLAG_ERROR;
726 fprintf(stderr, "error: stack underflow at %d (%s)\n", pos, op->name);
727
728 /* if we would do true verification (if we would be a vm), this is
729 where we would return the error
730 return 0;
731 */
732 }
733
734 stack += op->stack_plus;
735 scope += op->scope_stack_plus;
736
737 if(stack > stats->maxstack)
738 stats->maxstack = stack;
739 if(scope > stats->maxscope)
740 stats->maxscope = scope;
741
742 if(op->flags & OP_SET_DXNS)
743 stats->flags |= FLAGS_SET_DXNS;
744 if(op->flags & OP_NEED_ACTIVATION)
745 stats->flags |= FLAGS_ACTIVATION;
746
747 if(c->opcode == OPCODE_NEWCLASS) {
748 abc_class_t*cls = (abc_class_t*)(c->data[0]);
749 if(scope > cls->init_scope_depth)
750 cls->init_scope_depth = scope;
751 }
752 if(c->opcode == OPCODE_NEWFUNCTION) {
753 abc_method_t*m = (abc_method_t*)(c->data[0]);
754 if(m->body && scope > m->body->init_scope_depth)
755 m->body->init_scope_depth = scope;
756 }
757
758 if(op->flags & OP_REGISTER) {
759 char*p = op->params;
760 int pos = 0;
761 char ok=0;
762 while(*p) {
763 if(*p=='r') {
764 handleregister(stats, (ptroff_t)c->data[pos]);
765 ok = 1;
766 }
767 p++;
768 }
769 if(!ok) {
770 handleregister(stats, c->opcode&3);
771 }
772 }
773 if(op->flags&OP_RETURN) {
774 if(OP_RETURN==0x48/*returnvalue*/) {
775 if(stack!=1) {
776 stats->stack[pos].flags |= FLAG_ERROR;
777 fprintf(stderr, "return(value) with stackposition %d\n", stack);
778 }
779 } else if(OP_RETURN==0x47) {
780 if(stack!=0) {
781 stats->stack[pos].flags |= FLAG_ERROR;
782 fprintf(stderr, "return(void) with stackposition %d\n", stack);
783 }
784 }
785 }
786 if(op->flags & (OP_THROW|OP_RETURN))
787 return 1;
788 if(op->flags & OP_JUMP) {
789 if(!c->branch) {
790 stats->stack[pos].flags |= FLAG_ERROR;
791 fprintf(stderr, "Error: Invalid jump target in instruction %s at position %d.\n", op->name, pos);
792 return 0;
793 }
794 c = c->branch;
795 pos = c->pos;
796 continue;
797 }
798 if(op->flags & OP_BRANCH) {
799 if(!c->branch) {
800 stats->stack[pos].flags |= FLAG_ERROR;
801 fprintf(stderr, "Error: Invalid jump target in instruction %s at position %d\n", op->name, pos);
802 return 0;
803 }
804 int newpos = c->branch->pos;
805 if(!callcode(stats, newpos, stack, scope))
806 return 0;
807 }
808 if(op->flags & OP_LOOKUPSWITCH) {
809 lookupswitch_t*l = c->data[0];
810 if(!l->def) {
811 stats->stack[pos].flags |= FLAG_ERROR;
812 fprintf(stderr, "Error: Invalid jump target in instruction %s at position %d\n", op->name, pos);
813 return 0;
814 }
815 if(!callcode(stats, l->def->pos, stack, scope))
816 return 0;
817 code_list_t*t = l->targets;
818 while(t) {
819 if(!t->code) {
820 stats->stack[pos].flags |= FLAG_ERROR;
821 fprintf(stderr, "Error: Invalid jump target in instruction %s at position %d\n", op->name, pos);
822 return 0;
823 }
824 if(!callcode(stats, t->code->pos, stack, scope))
825 return 0;
826 t = t->next;
827 }
828 }
829
830 pos++;
831 if(pos<stats->num) {
832 assert(c->next == stats->stack[pos].code);
833 }
834 }
835 return 1;
836 }
837
code_get_stats(code_t * code,abc_exception_list_t * exceptions)838 static currentstats_t* code_get_stats(code_t*code, abc_exception_list_t*exceptions)
839 {
840 code = code_start(code);
841 int num = 0;
842 code_t*c = code;
843 while(c) {
844 num++;
845 c = c->next;
846 }
847 currentstats_t* current = malloc(sizeof(currentstats_t));
848 current->stack = rfx_calloc(sizeof(stackpos_t)*num);
849 current->maxlocal = 0;
850 current->maxstack = 0;
851 current->maxscope = 0;
852 current->num = num;
853 current->flags = 0;
854
855 //#define DEBUG_BYTES
856 #ifdef DEBUG_BYTES
857 int t;
858 c = code;
859 for(t=0;t<num;t++) {
860 opcode_t*op = opcode_get(c->opcode);
861 if(op->flags & (OP_JUMP|OP_BRANCH)) {
862 printf("%05d) %s %p\n", t, op->name, c->branch);
863 } else if(op->params[0]=='2') {
864 printf("%05d) %s %s\n", t, op->name, multiname_tostring(c->data[0]));
865 } else if(op->params[0]=='N') {
866 printf("%05d) %s %s\n", t, op->name, namespace_tostring(c->data[0]));
867 } else {
868 printf("%05d) %s\n", t, op->name);
869 }
870 c = c->next;
871 }
872 //printf("%05d) %02x\n", t, tag->data[start+t]);
873 #endif
874
875 num = 0;
876 c = code;
877 while(c) {
878 //crosslink
879 current->stack[num].code = c;
880 c->pos = num;
881 num++;
882 c = c->next;
883 }
884
885 if(!callcode(current, 0, 0, 0)) {
886 free(current);
887 return 0;
888 }
889 abc_exception_list_t*e = exceptions;
890 while(e) {
891 if(e->abc_exception->target)
892 callcode(current, e->abc_exception->target->pos, 1, 0);
893 e = e->next;
894 }
895
896 return current;
897 }
898
stats_free(currentstats_t * stats)899 void stats_free(currentstats_t*stats)
900 {
901 if(stats) {
902 free(stats->stack);stats->stack=0;
903 free(stats);
904 }
905 }
906
code_dump(code_t * c)907 int code_dump(code_t*c)
908 {
909 code_t*cc = code_start(c);
910 while(cc) {
911 assert(!cc->next || cc->next->prev == cc);
912 cc = cc->next;
913 }
914
915 return code_dump2(c, 0, 0, "", stdout);
916 }
code_dump2(code_t * c,abc_exception_list_t * exceptions,abc_file_t * file,char * prefix,FILE * fo)917 int code_dump2(code_t*c, abc_exception_list_t*exceptions, abc_file_t*file, char*prefix, FILE*fo)
918 {
919 abc_exception_list_t*e = exceptions;
920 c = code_start(c);
921 currentstats_t*stats = code_get_stats(c, exceptions);
922
923 int pos = 0;
924 while(c) {
925 U8 opcode = c->opcode;
926 char found = 0;
927 opcode_t*op = opcode_get(opcode);
928
929 e = exceptions;
930 while(e) {
931 if(c==e->abc_exception->from)
932 fprintf(fo, "%s TRY {\n", prefix);
933 if(c==e->abc_exception->target) {
934 char*s1 = multiname_tostring(e->abc_exception->exc_type);
935 char*s2 = multiname_tostring(e->abc_exception->var_name);
936 fprintf(fo, "%s CATCH(%s %s)\n", prefix, s1, s2);
937 free(s1);
938 free(s2);
939 }
940 e = e->next;
941 }
942
943 if(!op) {
944 fprintf(stderr, "Can't parse opcode %02x.\n", opcode);
945 return 0;
946 } else {
947 char*p = op->params;
948 char first = 1;
949 int i=0;
950
951 if(stats) {
952 int f = stats->stack[c->pos].flags;
953 fprintf(fo, "%s%05d) %c %d:%d %s ", prefix, c->pos,
954 (f&FLAG_ERROR)?'E':((f&FLAG_SEEN)?'+':'|'),
955 stats->stack[c->pos].stackpos,
956 stats->stack[c->pos].scopepos,
957 op->name);
958 } else {
959 fprintf(fo, "%s%05d) ? ?:? %s ", prefix, c->pos, op->name);
960 }
961
962 while(*p) {
963 void*data = c->data[i];
964 if(i>0)
965 printf(", ");
966
967 if(*p == 'n') {
968 int n = (ptroff_t)data;
969 fprintf(fo, "%d params", n);
970 } else if(*p == '2') {
971 multiname_t*n = (multiname_t*)data;
972 char* m = multiname_tostring(n);
973 fprintf(fo, "%s", m);
974 free(m);
975 } else if(*p == 'N') {
976 namespace_t*ns = (namespace_t*)data;
977 char* m = namespace_tostring(ns);
978 fprintf(fo, "%s", m);
979 free(m);
980 } else if(*p == 'm') {
981 abc_method_t*m = (abc_method_t*)data;
982 fprintf(fo, "[method %08x %s]", m->index, m->name);
983 } else if(*p == 'c') {
984 abc_class_t*cls = (abc_class_t*)data;
985 char*classname = multiname_tostring(cls->classname);
986 fprintf(fo, "[classinfo %08x %s]", cls->index, classname);
987 free(classname);
988 } else if(*p == 'i') {
989 abc_method_body_t*b = (abc_method_body_t*)data;
990 fprintf(fo, "[methodbody]");
991 } else if(*p == 'u' || *p == 'I' || *p == 'U') {
992 int n = (ptroff_t)data;
993 fprintf(fo, "%d", n);
994 } else if(*p == 'f') {
995 double f = *(double*)data;
996 fprintf(fo, "%f", f);
997 } else if(*p == 'r') {
998 int n = (ptroff_t)data;
999 fprintf(fo, "r%d", n);
1000 } else if(*p == 'b') {
1001 int b = (signed char)(ptroff_t)data;
1002 fprintf(fo, "%d", b);
1003 } else if(*p == 'j') {
1004 if(c->branch)
1005 fprintf(fo, "->%d", c->branch->pos);
1006 else
1007 fprintf(fo, "%p", c->branch);
1008 } else if(*p == 's') {
1009 char*s = string_escape((string_t*)data);
1010 fprintf(fo, "\"%s\"", s);
1011 free(s);
1012 } else if(*p == 'D') {
1013 fprintf(fo, "[register %02x=%s]", (int)(ptroff_t)c->data[1], (char*)c->data[0]);
1014 } else if(*p == 'S') {
1015 lookupswitch_t*l = c->data[0];
1016 fprintf(fo, "[");
1017 if(l->def)
1018 fprintf(fo, "default->%d", l->def->pos);
1019 else
1020 fprintf(fo, "default->00000000");
1021 code_list_t*t = l->targets;
1022 while(t) {
1023 if(t->code)
1024 fprintf(fo, ",->%d", t->code->pos);
1025 else
1026 fprintf(fo, ",->00000000");
1027 t = t->next;
1028 }
1029 fprintf(fo, "]");
1030 } else {
1031 fprintf(stderr, "Can't parse opcode param type \"%c\"\n", *p);
1032 return 0;
1033 }
1034 p++;
1035 i++;
1036 first = 0;
1037 }
1038 fprintf(fo, "\n");
1039 }
1040
1041 e = exceptions;
1042 while(e) {
1043 if(c==e->abc_exception->to) {
1044 if(e->abc_exception->target)
1045 fprintf(fo, "%s } // END TRY (HANDLER: %d)\n", prefix, e->abc_exception->target->pos);
1046 else
1047 fprintf(fo, "%s } // END TRY (HANDLER: 00000000)\n", prefix);
1048 }
1049 e = e->next;
1050 }
1051
1052 pos++;
1053 c = c->next;
1054 }
1055 stats_free(stats);
1056 return 1;
1057 }
1058
code_get_statistics(code_t * code,abc_exception_list_t * exceptions)1059 codestats_t* code_get_statistics(code_t*code, abc_exception_list_t*exceptions)
1060 {
1061 currentstats_t*current = code_get_stats(code, exceptions);
1062 if(!current)
1063 return 0;
1064 codestats_t*stats = rfx_calloc(sizeof(codestats_t));
1065 stats->local_count = current->maxlocal;
1066 stats->max_stack = current->maxstack;
1067 stats->max_scope_depth = current->maxscope;
1068 stats->flags = current->flags;
1069
1070 stats_free(current);current=0;
1071 return stats;
1072 }
1073
codestats_free(codestats_t * s)1074 void codestats_free(codestats_t*s)
1075 {
1076 free(s);
1077 }
1078
add_opcode(code_t * atag,U8 op)1079 code_t* add_opcode(code_t*atag, U8 op)
1080 {
1081 code_t*tmp = (code_t*)rfx_calloc(sizeof(code_t));
1082 tmp->opcode = op;
1083 if(atag) {
1084 tmp->prev = atag;
1085 tmp->next = atag->next;
1086 if(tmp->next)
1087 tmp->next->prev = tmp;
1088 atag->next = tmp;
1089 } else {
1090 tmp->prev = 0;
1091 tmp->next = 0;
1092 }
1093 return tmp;
1094 }
1095
codestats_print(codestats_t * stats)1096 void codestats_print(codestats_t*stats)
1097 {
1098 printf("max_stack: %d\n", stats->max_stack);
1099 printf("local_count: %d\n", stats->local_count);
1100 printf("scope_depth: %d\n", stats->max_scope_depth);
1101 }
1102
code_end(code_t * code)1103 code_t* code_end(code_t*code)
1104 {
1105 if(!code)
1106 return 0;
1107 while(code->next)
1108 code = code->next;
1109 return code;
1110 }
code_start(code_t * code)1111 code_t* code_start(code_t*code)
1112 {
1113 if(!code)
1114 return 0;
1115 while(code->prev)
1116 code = code->prev;
1117 return code;
1118 }
1119
code_append(code_t * code,code_t * toappend)1120 code_t* code_append(code_t*code, code_t*toappend)
1121 {
1122 if(!code)
1123 return code_end(toappend);
1124 if(!toappend)
1125 return code_end(code);
1126 //find end of first list
1127 while(code->next) {
1128 code = code->next;
1129 }
1130 code_t*start=toappend;
1131 //and start of second list
1132 while(start->prev) {
1133 start = start->prev;
1134 }
1135 code->next = start;
1136 start->prev = code;
1137 return code_end(toappend);
1138 }
1139
lookupswitch_dup(lookupswitch_t * l)1140 lookupswitch_t*lookupswitch_dup(lookupswitch_t*l)
1141 {
1142 lookupswitch_t*n = malloc(sizeof(lookupswitch_t));
1143 fprintf(stderr, "Error: lookupswitch dupping not supported yet\n");
1144 n->targets = list_clone(l->targets);
1145 return 0;
1146 }
1147
code_dup(code_t * c)1148 code_t*code_dup(code_t*c)
1149 {
1150 if(!c) return 0;
1151
1152 dict_t*pos2pos = dict_new2(&ptr_type);
1153
1154 code_t*last = 0;
1155 c = code_start(c);
1156 code_t*start = 0;
1157 char does_branch = 0;
1158 while(c) {
1159 NEW(code_t, n);
1160 memcpy(n, c, sizeof(code_t));
1161 if(!start)
1162 start=n;
1163
1164 if(c->opcode == OPCODE_LABEL || c->opcode == OPCODE_NOP) {
1165 dict_put(pos2pos, c, n);
1166 }
1167 if(c->branch) {
1168 does_branch = 1;
1169 }
1170
1171 opcode_t*op = opcode_get(c->opcode);
1172
1173 char*p = op?op->params:"";
1174 int pos=0;
1175 while(*p) {
1176 if(*p == '2') { //multiname
1177 c->data[pos] = multiname_clone(c->data[pos]);
1178 } else if(*p == 'N') { //multiname
1179 c->data[pos] = namespace_clone(c->data[pos]);
1180 } else if(*p == 's') {
1181 c->data[pos] = string_dup3(c->data[pos]);
1182 } else if(*p == 'D') {
1183 c->data[pos] = strdup(c->data[pos]);
1184 } else if(*p == 'f') {
1185 double old = *(double*)c->data[pos];
1186 c->data[pos] = malloc(sizeof(double));
1187 *(double*)c->data[pos] = old;
1188 } else if(strchr("S", *p)) {
1189 c->data[pos] = lookupswitch_dup(c->data[pos]);
1190 }
1191 p++;pos++;
1192 }
1193
1194 n->prev = last;
1195 if(last) {
1196 last->next = n;
1197 }
1198 last = n;
1199 c = c->next;
1200 }
1201
1202 if(does_branch) {
1203 c = start;
1204 while(c) {
1205 if(c->branch) {
1206 code_t*target = dict_lookup(pos2pos, c->branch);
1207 if(!target) {
1208 fprintf(stderr, "Error: Can't find branch target in code_dup\n");
1209 return 0;
1210 }
1211 c->branch = target;
1212 }
1213 c = c->next;
1214 }
1215 }
1216 dict_destroy(pos2pos);
1217 return last;
1218 }
1219
code_cut(code_t * c)1220 code_t*code_cut(code_t*c)
1221 {
1222 if(!c) return c;
1223 code_t*prev = c->prev;
1224 code_t*next = c->next;
1225 c->prev = 0;
1226 c->next = 0;
1227 if(prev) prev->next=next;
1228 if(next) next->prev=prev;
1229 code_free(c);
1230
1231 if(next) return code_end(next);
1232 else return prev;
1233 }
1234
code_cutlast(code_t * c)1235 code_t*code_cutlast(code_t*c)
1236 {
1237 if(!c) return c;
1238 assert(!c->next);
1239 return code_cut(c);
1240 }
1241
is_getlocal(code_t * c)1242 char is_getlocal(code_t*c)
1243 {
1244 if(!c) return 0;
1245 if(c->opcode == OPCODE_GETLOCAL ||
1246 c->opcode == OPCODE_GETLOCAL_0 ||
1247 c->opcode == OPCODE_GETLOCAL_1 ||
1248 c->opcode == OPCODE_GETLOCAL_2 ||
1249 c->opcode == OPCODE_GETLOCAL_3) {
1250 return 1;
1251 }
1252 return 0;
1253 }
1254
cut_last_push(code_t * c)1255 code_t* cut_last_push(code_t*c)
1256 {
1257 assert(!c->next);
1258 while(c) {
1259 if(!c) break;
1260 opcode_t*op = opcode_get(c->opcode);
1261 /* cut conversion type operations */
1262 if(op->stack_minus == -1 && op->stack_plus == 1 && !(op->flags)) {
1263 c = code_cutlast(c);
1264 continue;
1265 }
1266 /* cut any type of push */
1267 else if(op->stack_minus == 0 && op->stack_plus == 1 && !(op->flags)) {
1268 return code_cutlast(c);
1269 }
1270 /* cut register lookups */
1271 else if(c->opcode == OPCODE_GETLOCAL ||
1272 c->opcode == OPCODE_GETLOCAL_0 ||
1273 c->opcode == OPCODE_GETLOCAL_1 ||
1274 c->opcode == OPCODE_GETLOCAL_2 ||
1275 c->opcode == OPCODE_GETLOCAL_3) {
1276 return code_cutlast(c);
1277 }
1278 /* discard function call values */
1279 else if(c->opcode == OPCODE_CALLPROPERTY) {
1280 c->opcode = OPCODE_CALLPROPVOID;
1281 return c;
1282 } else if(c->opcode == OPCODE_CALLSUPER) {
1283 c->opcode = OPCODE_CALLSUPERVOID;
1284 return c;
1285 } else if((c->opcode == OPCODE_NEWOBJECT ||
1286 c->opcode == OPCODE_NEWARRAY) &&
1287 !c->data[0]) {
1288 // we can discard these if they're not eating up stack parameters
1289 return code_cutlast(c);
1290 } else if(op->stack_minus ==0 && op->stack_plus == 0 &&
1291 !(op->flags&~(OP_REGISTER|OP_SET_DXNS)) && c->prev) {
1292 // trim code *before* the kill, inclocal, declocal, dxns
1293 code_t*p = c->prev;
1294 p->next = 0;
1295 c->prev = 0;
1296 return code_append(cut_last_push(p), c);
1297 } else
1298 break;
1299 }
1300 c = abc_pop(c);
1301 return c;
1302 }
1303
1304
1305