Mercurial > lcfOS
annotate python/ppci/c3/codegenerator.py @ 389:2ec730e45ea1
Added check for recursive struct
| author | Windel Bouwman |
|---|---|
| date | Fri, 16 May 2014 12:29:31 +0200 |
| parents | c49459768aaa |
| children | 6ae782a085e0 |
| rev | line source |
|---|---|
| 255 | 1 import logging |
| 354 | 2 import struct |
| 301 | 3 from .. import ir |
| 307 | 4 from .. import irutils |
| 308 | 5 from . import astnodes as ast |
| 230 | 6 |
| 228 | 7 |
| 307 | 8 class SemanticError(Exception): |
| 308 | 9 """ Error thrown when a semantic issue is observed """ |
| 307 | 10 def __init__(self, msg, loc): |
| 308 | 11 super().__init__() |
| 307 | 12 self.msg = msg |
| 13 self.loc = loc | |
| 14 | |
| 15 | |
| 16 class CodeGenerator(irutils.Builder): | |
| 288 | 17 """ |
| 274 | 18 Generates intermediate (IR) code from a package. The entry function is |
| 19 'genModule'. The main task of this part is to rewrite complex control | |
| 20 structures, such as while and for loops into simple conditional | |
| 21 jump statements. Also complex conditional statements are simplified. | |
| 22 Such as 'and' and 'or' statements are rewritten in conditional jumps. | |
| 23 And structured datatypes are rewritten. | |
| 307 | 24 |
| 25 Type checking is done in one run with code generation. | |
| 274 | 26 """ |
| 307 | 27 def __init__(self, diag): |
| 261 | 28 self.logger = logging.getLogger('c3cgen') |
| 307 | 29 self.diag = diag |
| 261 | 30 |
| 217 | 31 def gencode(self, pkg): |
| 308 | 32 """ Generate code for a single module """ |
| 268 | 33 self.prepare() |
| 308 | 34 assert type(pkg) is ast.Package |
| 307 | 35 self.pkg = pkg |
| 36 self.intType = pkg.scope['int'] | |
| 37 self.boolType = pkg.scope['bool'] | |
| 389 | 38 self.pointerSize = 4 |
| 39 self.logger.debug('Generating ir-code for {}'.format(pkg.name), | |
| 40 extra={'c3_ast': pkg}) | |
| 288 | 41 self.varMap = {} # Maps variables to storage locations. |
| 268 | 42 self.m = ir.Module(pkg.name) |
| 307 | 43 try: |
| 389 | 44 for typ in pkg.Types: |
| 45 self.check_type(typ) | |
| 362 | 46 # Only generate function if function contains a body: |
| 389 | 47 real_functions = list(filter( |
| 48 lambda f: f.body, pkg.innerScope.Functions)) | |
| 307 | 49 for v in pkg.innerScope.Variables: |
| 364 | 50 v2 = ir.GlobalVariable(v.name) |
| 51 self.varMap[v] = v2 | |
| 363 | 52 if not v.isLocal: |
| 364 | 53 self.m.add_variable(v2) |
| 362 | 54 for s in real_functions: |
| 308 | 55 self.gen_function(s) |
| 307 | 56 except SemanticError as e: |
| 57 self.error(e.msg, e.loc) | |
| 313 | 58 if self.pkg.ok: |
| 59 return self.m | |
| 308 | 60 |
| 61 def error(self, msg, loc=None): | |
| 62 self.pkg.ok = False | |
| 63 self.diag.error(msg, loc) | |
| 307 | 64 |
| 308 | 65 def gen_function(self, fn): |
| 268 | 66 # TODO: handle arguments |
| 363 | 67 f = self.newFunction(fn.name) |
| 272 | 68 f.return_value = self.newTemp() |
| 268 | 69 self.setFunction(f) |
| 269 | 70 l2 = self.newBlock() |
| 71 self.emit(ir.Jump(l2)) | |
| 72 self.setBlock(l2) | |
| 268 | 73 # generate room for locals: |
| 174 | 74 |
| 268 | 75 for sym in fn.innerScope: |
| 389 | 76 self.check_type(sym.typ) |
| 272 | 77 if sym.isParameter: |
| 316 | 78 p = ir.Parameter(sym.name) |
| 79 variable = ir.LocalVariable(sym.name + '_copy') | |
| 80 f.addParameter(p) | |
| 81 f.addLocal(variable) | |
| 82 # Move parameter into local copy: | |
| 83 self.emit(ir.Move(ir.Mem(variable), p)) | |
| 274 | 84 elif sym.isLocal: |
| 308 | 85 variable = ir.LocalVariable(sym.name) |
| 86 f.addLocal(variable) | |
| 87 elif isinstance(sym, ast.Variable): | |
| 88 variable = ir.LocalVariable(sym.name) | |
| 89 f.addLocal(variable) | |
| 274 | 90 else: |
| 275 | 91 raise NotImplementedError('{}'.format(sym)) |
| 308 | 92 self.varMap[sym] = variable |
| 268 | 93 |
| 94 self.genCode(fn.body) | |
| 272 | 95 self.emit(ir.Move(f.return_value, ir.Const(0))) |
| 269 | 96 self.emit(ir.Jump(f.epiloog)) |
| 268 | 97 self.setFunction(None) |
| 158 | 98 |
| 217 | 99 def genCode(self, code): |
| 308 | 100 """ Wrapper around gen_stmt to catch errors """ |
| 307 | 101 try: |
| 308 | 102 self.gen_stmt(code) |
| 307 | 103 except SemanticError as e: |
| 104 self.error(e.msg, e.loc) | |
| 105 | |
| 308 | 106 def gen_stmt(self, code): |
| 107 """ Generate code for a statement """ | |
| 108 assert isinstance(code, ast.Statement) | |
| 268 | 109 self.setLoc(code.loc) |
| 308 | 110 if type(code) is ast.Compound: |
| 221 | 111 for s in code.statements: |
| 112 self.genCode(s) | |
| 308 | 113 elif type(code) is ast.Empty: |
| 306 | 114 pass |
| 308 | 115 elif type(code) is ast.Assignment: |
| 268 | 116 lval = self.genExprCode(code.lval) |
| 307 | 117 rval = self.genExprCode(code.rval) |
| 389 | 118 if not self.equal_types(code.lval.typ, code.rval.typ): |
| 119 raise SemanticError('Cannot assign {} to {}' | |
| 120 .format(code.rval.typ, code.lval.typ), | |
| 121 code.loc) | |
| 307 | 122 if not code.lval.lvalue: |
| 389 | 123 raise SemanticError('No valid lvalue {}'.format(code.lval), |
| 124 code.lval.loc) | |
| 268 | 125 self.emit(ir.Move(lval, rval)) |
| 308 | 126 elif type(code) is ast.ExpressionStatement: |
| 275 | 127 self.emit(ir.Exp(self.genExprCode(code.ex))) |
| 308 | 128 elif type(code) is ast.If: |
| 268 | 129 bbtrue = self.newBlock() |
| 130 bbfalse = self.newBlock() | |
| 131 te = self.newBlock() | |
| 308 | 132 self.gen_cond_code(code.condition, bbtrue, bbfalse) |
| 268 | 133 self.setBlock(bbtrue) |
| 134 self.genCode(code.truestatement) | |
| 135 self.emit(ir.Jump(te)) | |
| 136 self.setBlock(bbfalse) | |
| 306 | 137 self.genCode(code.falsestatement) |
| 268 | 138 self.emit(ir.Jump(te)) |
| 139 self.setBlock(te) | |
| 308 | 140 elif type(code) is ast.Return: |
| 303 | 141 re = self.genExprCode(code.expr) |
| 142 self.emit(ir.Move(self.fn.return_value, re)) | |
| 143 self.emit(ir.Jump(self.fn.epiloog)) | |
| 144 b = self.newBlock() | |
| 145 self.setBlock(b) | |
| 308 | 146 elif type(code) is ast.While: |
| 268 | 147 bbdo = self.newBlock() |
| 148 bbtest = self.newBlock() | |
| 149 te = self.newBlock() | |
| 150 self.emit(ir.Jump(bbtest)) | |
| 151 self.setBlock(bbtest) | |
| 308 | 152 self.gen_cond_code(code.condition, bbdo, te) |
| 268 | 153 self.setBlock(bbdo) |
| 228 | 154 self.genCode(code.statement) |
| 268 | 155 self.emit(ir.Jump(bbtest)) |
| 156 self.setBlock(te) | |
| 315 | 157 elif type(code) is ast.For: |
| 158 bbdo = self.newBlock() | |
| 159 bbtest = self.newBlock() | |
| 160 te = self.newBlock() | |
| 161 self.genCode(code.init) | |
| 162 self.emit(ir.Jump(bbtest)) | |
| 163 self.setBlock(bbtest) | |
| 164 self.gen_cond_code(code.condition, bbdo, te) | |
| 165 self.setBlock(bbdo) | |
| 166 self.genCode(code.statement) | |
| 360 | 167 self.genCode(code.final) |
| 315 | 168 self.emit(ir.Jump(bbtest)) |
| 169 self.setBlock(te) | |
| 222 | 170 else: |
| 268 | 171 raise NotImplementedError('Unknown stmt {}'.format(code)) |
| 230 | 172 |
| 308 | 173 def gen_cond_code(self, expr, bbtrue, bbfalse): |
| 174 """ Generate conditional logic. | |
| 175 Implement sequential logical operators. """ | |
| 176 if type(expr) is ast.Binop: | |
| 268 | 177 if expr.op == 'or': |
| 178 l2 = self.newBlock() | |
| 308 | 179 self.gen_cond_code(expr.a, bbtrue, l2) |
| 389 | 180 if not self.equal_types(expr.a.typ, self.boolType): |
| 307 | 181 raise SemanticError('Must be boolean', expr.a.loc) |
| 268 | 182 self.setBlock(l2) |
| 308 | 183 self.gen_cond_code(expr.b, bbtrue, bbfalse) |
| 389 | 184 if not self.equal_types(expr.b.typ, self.boolType): |
| 307 | 185 raise SemanticError('Must be boolean', expr.b.loc) |
| 268 | 186 elif expr.op == 'and': |
| 187 l2 = self.newBlock() | |
| 308 | 188 self.gen_cond_code(expr.a, l2, bbfalse) |
| 389 | 189 if not self.equal_types(expr.a.typ, self.boolType): |
| 307 | 190 self.error('Must be boolean', expr.a.loc) |
| 268 | 191 self.setBlock(l2) |
| 308 | 192 self.gen_cond_code(expr.b, bbtrue, bbfalse) |
| 389 | 193 if not self.equal_types(expr.b.typ, self.boolType): |
| 307 | 194 raise SemanticError('Must be boolean', expr.b.loc) |
| 305 | 195 elif expr.op in ['==', '>', '<', '!=', '<=', '>=']: |
| 228 | 196 ta = self.genExprCode(expr.a) |
| 197 tb = self.genExprCode(expr.b) | |
| 389 | 198 if not self.equal_types(expr.a.typ, expr.b.typ): |
| 307 | 199 raise SemanticError('Types unequal {} != {}' |
| 389 | 200 .format(expr.a.typ, expr.b.typ), |
| 201 expr.loc) | |
| 268 | 202 self.emit(ir.CJump(ta, expr.op, tb, bbtrue, bbfalse)) |
| 203 else: | |
| 311 | 204 raise SemanticError('non-bool: {}'.format(expr.op), expr.loc) |
| 307 | 205 expr.typ = self.boolType |
| 308 | 206 elif type(expr) is ast.Literal: |
| 207 self.genExprCode(expr) | |
| 288 | 208 if expr.val: |
| 268 | 209 self.emit(ir.Jump(bbtrue)) |
| 288 | 210 else: |
| 268 | 211 self.emit(ir.Jump(bbfalse)) |
| 228 | 212 else: |
| 288 | 213 raise NotImplementedError('Unknown cond {}'.format(expr)) |
| 354 | 214 |
| 215 # Check that the condition is a boolean value: | |
| 389 | 216 if not self.equal_types(expr.typ, self.boolType): |
| 307 | 217 self.error('Condition must be boolean', expr.loc) |
| 230 | 218 |
| 217 | 219 def genExprCode(self, expr): |
| 308 | 220 """ Generate code for an expression. Return the generated ir-value """ |
| 221 assert isinstance(expr, ast.Expression) | |
| 222 if type(expr) is ast.Binop: | |
| 307 | 223 expr.lvalue = False |
| 224 if expr.op in ['+', '-', '*', '/', '<<', '>>', '|', '&']: | |
| 225 ra = self.genExprCode(expr.a) | |
| 226 rb = self.genExprCode(expr.b) | |
| 389 | 227 if self.equal_types(expr.a.typ, self.intType) and \ |
| 228 self.equal_types(expr.b.typ, self.intType): | |
| 307 | 229 expr.typ = expr.a.typ |
| 230 else: | |
| 231 raise SemanticError('Can only add integers', expr.loc) | |
| 232 else: | |
| 233 raise NotImplementedError("Cannot use equality as expressions") | |
| 268 | 234 return ir.Binop(ra, expr.op, rb) |
| 308 | 235 elif type(expr) is ast.Unop: |
| 307 | 236 if expr.op == '&': |
| 237 ra = self.genExprCode(expr.a) | |
| 308 | 238 expr.typ = ast.PointerType(expr.a.typ) |
| 307 | 239 if not expr.a.lvalue: |
| 240 raise SemanticError('No valid lvalue', expr.a.loc) | |
| 241 expr.lvalue = False | |
| 242 assert type(ra) is ir.Mem | |
| 243 return ra.e | |
| 244 else: | |
| 245 raise NotImplementedError('Unknown unop {0}'.format(expr.op)) | |
| 308 | 246 elif type(expr) is ast.Identifier: |
| 307 | 247 # Generate code for this identifier. |
| 248 tg = self.resolveSymbol(expr) | |
| 249 expr.kind = type(tg) | |
| 250 expr.typ = tg.typ | |
| 279 | 251 # This returns the dereferenced variable. |
| 308 | 252 if isinstance(tg, ast.Variable): |
| 313 | 253 expr.lvalue = True |
| 307 | 254 return ir.Mem(self.varMap[tg]) |
| 313 | 255 elif isinstance(tg, ast.Constant): |
| 256 c_val = self.genExprCode(tg.value) | |
| 257 return self.evalConst(c_val) | |
|
280
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279
diff
changeset
|
258 else: |
| 308 | 259 raise NotImplementedError(str(tg)) |
| 260 elif type(expr) is ast.Deref: | |
| 222 | 261 # dereference pointer type: |
| 225 | 262 addr = self.genExprCode(expr.ptr) |
| 316 | 263 ptr_typ = self.the_type(expr.ptr.typ) |
| 307 | 264 expr.lvalue = True |
| 308 | 265 if type(ptr_typ) is ast.PointerType: |
| 307 | 266 expr.typ = ptr_typ.ptype |
| 267 return ir.Mem(addr) | |
| 268 else: | |
| 269 raise SemanticError('Cannot deref non-pointer', expr.loc) | |
| 308 | 270 elif type(expr) is ast.Member: |
| 279 | 271 base = self.genExprCode(expr.base) |
| 307 | 272 expr.lvalue = expr.base.lvalue |
| 316 | 273 basetype = self.the_type(expr.base.typ) |
| 308 | 274 if type(basetype) is ast.StructureType: |
| 307 | 275 if basetype.hasField(expr.field): |
| 276 expr.typ = basetype.fieldType(expr.field) | |
| 277 else: | |
| 278 raise SemanticError('{} does not contain field {}' | |
| 389 | 279 .format(basetype, expr.field), |
| 280 expr.loc) | |
| 307 | 281 else: |
| 308 | 282 raise SemanticError('Cannot select {} of non-structure type {}' |
| 283 .format(expr.field, basetype), expr.loc) | |
| 307 | 284 |
| 279 | 285 assert type(base) is ir.Mem, type(base) |
| 316 | 286 bt = self.the_type(expr.base.typ) |
| 268 | 287 offset = ir.Const(bt.fieldOffset(expr.field)) |
| 308 | 288 return ir.Mem(ir.Add(base.e, offset)) |
| 354 | 289 elif type(expr) is ast.Index: |
| 290 """ Array indexing """ | |
| 291 base = self.genExprCode(expr.base) | |
| 292 idx = self.genExprCode(expr.i) | |
| 293 base_typ = self.the_type(expr.base.typ) | |
| 294 if not isinstance(base_typ, ast.ArrayType): | |
| 389 | 295 raise SemanticError('Cannot index non-array type {}' |
| 296 .format(base_typ), | |
| 297 expr.base.loc) | |
| 354 | 298 idx_type = self.the_type(expr.i.typ) |
| 389 | 299 if not self.equal_types(idx_type, self.intType): |
| 300 raise SemanticError('Index must be int not {}' | |
| 301 .format(idx_type), expr.i.loc) | |
| 354 | 302 assert type(base) is ir.Mem |
| 303 element_type = self.the_type(base_typ.element_type) | |
| 304 element_size = self.size_of(element_type) | |
| 305 expr.typ = base_typ.element_type | |
| 306 expr.lvalue = True | |
| 307 | |
| 308 return ir.Mem(ir.Add(base.e, ir.Mul(idx, ir.Const(element_size)))) | |
| 308 | 309 elif type(expr) is ast.Literal: |
| 307 | 310 expr.lvalue = False |
| 389 | 311 typemap = {int: 'int', |
| 312 float: 'double', | |
| 313 bool: 'bool', | |
| 314 str: 'string'} | |
| 307 | 315 if type(expr.val) in typemap: |
| 316 expr.typ = self.pkg.scope[typemap[type(expr.val)]] | |
| 317 else: | |
| 389 | 318 raise SemanticError('Unknown literal type {}' |
| 319 .format(expr.val), expr.loc) | |
| 354 | 320 # Construct correct const value: |
| 321 if type(expr.val) is str: | |
| 389 | 322 cval = self.pack_string(expr.val) |
| 354 | 323 return ir.Addr(ir.Const(cval)) |
| 324 else: | |
| 325 return ir.Const(expr.val) | |
| 308 | 326 elif type(expr) is ast.TypeCast: |
| 327 return self.gen_type_cast(expr) | |
| 328 elif type(expr) is ast.FunctionCall: | |
| 329 return self.gen_function_call(expr) | |
| 225 | 330 else: |
| 259 | 331 raise NotImplementedError('Unknown expr {}'.format(expr)) |
| 307 | 332 |
| 389 | 333 def pack_string(self, txt): |
| 334 """ Pack a string using 4 bytes length followed by text data """ | |
| 335 length = struct.pack('<I', len(txt)) | |
| 336 data = txt.encode('ascii') | |
| 337 return length + data | |
| 338 | |
| 308 | 339 def gen_type_cast(self, expr): |
| 340 """ Generate code for type casting """ | |
| 341 ar = self.genExprCode(expr.a) | |
| 316 | 342 from_type = self.the_type(expr.a.typ) |
| 343 to_type = self.the_type(expr.to_type) | |
| 389 | 344 if isinstance(from_type, ast.PointerType) and \ |
| 308 | 345 isinstance(to_type, ast.PointerType): |
| 346 expr.typ = expr.to_type | |
| 347 return ar | |
| 389 | 348 elif self.equal_types(self.intType, from_type) and \ |
| 349 isinstance(to_type, ast.PointerType): | |
| 350 expr.typ = expr.to_type | |
| 351 return ar | |
| 352 elif self.equal_types(self.intType, to_type) \ | |
| 364 | 353 and isinstance(from_type, ast.PointerType): |
| 354 expr.typ = expr.to_type | |
| 355 return ar | |
| 354 | 356 elif type(from_type) is ast.BaseType and from_type.name == 'byte' and \ |
| 357 type(to_type) is ast.BaseType and to_type.name == 'int': | |
| 358 expr.typ = expr.to_type | |
| 359 return ar | |
| 308 | 360 else: |
| 361 raise SemanticError('Cannot cast {} to {}' | |
| 362 .format(from_type, to_type), expr.loc) | |
| 353 | 363 |
| 308 | 364 def gen_function_call(self, expr): |
| 365 """ Generate code for a function call """ | |
| 366 # Evaluate the arguments: | |
| 367 args = [self.genExprCode(e) for e in expr.args] | |
| 368 # Check arguments: | |
| 369 tg = self.resolveSymbol(expr.proc) | |
| 370 if type(tg) is not ast.Function: | |
| 371 raise SemanticError('cannot call {}'.format(tg)) | |
| 372 ftyp = tg.typ | |
|
336
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parents:
334
diff
changeset
|
373 fname = tg.package.name + '_' + tg.name |
| 308 | 374 ptypes = ftyp.parametertypes |
| 375 if len(expr.args) != len(ptypes): | |
| 376 raise SemanticError('{} requires {} arguments, {} given' | |
| 389 | 377 .format(fname, len(ptypes), len(expr.args)), |
| 378 expr.loc) | |
| 308 | 379 for arg, at in zip(expr.args, ptypes): |
| 389 | 380 if not self.equal_types(arg.typ, at): |
| 308 | 381 raise SemanticError('Got {}, expected {}' |
| 389 | 382 .format(arg.typ, at), arg.loc) |
| 308 | 383 # determine return type: |
| 384 expr.typ = ftyp.returntype | |
| 385 return ir.Call(fname, args) | |
| 386 | |
| 313 | 387 def evalConst(self, c): |
| 388 if isinstance(c, ir.Const): | |
| 389 return c | |
| 390 else: | |
| 391 raise SemanticError('Cannot evaluate constant {}'.format(c)) | |
| 392 | |
| 307 | 393 def resolveSymbol(self, sym): |
| 308 | 394 if type(sym) is ast.Member: |
| 307 | 395 base = self.resolveSymbol(sym.base) |
| 308 | 396 if type(base) is not ast.Package: |
| 397 raise SemanticError('Base is not a package', sym.loc) | |
| 307 | 398 scope = base.innerScope |
| 399 name = sym.field | |
| 308 | 400 elif type(sym) is ast.Identifier: |
| 307 | 401 scope = sym.scope |
| 402 name = sym.target | |
| 403 else: | |
| 404 raise NotImplementedError(str(sym)) | |
| 405 if name in scope: | |
| 406 s = scope[name] | |
| 407 else: | |
| 408 raise SemanticError('{} undefined'.format(name), sym.loc) | |
| 308 | 409 assert isinstance(s, ast.Symbol) |
| 307 | 410 return s |
| 411 | |
| 316 | 412 def size_of(self, t): |
| 413 """ Determine the byte size of a type """ | |
| 414 t = self.the_type(t) | |
| 415 if type(t) is ast.BaseType: | |
| 416 return t.bytesize | |
| 417 elif type(t) is ast.StructureType: | |
| 418 return sum(self.size_of(mem.typ) for mem in t.mems) | |
| 354 | 419 elif type(t) is ast.ArrayType: |
| 420 return t.size * self.size_of(t.element_type) | |
| 389 | 421 elif type(t) is ast.PointerType: |
| 422 return self.pointerSize | |
| 316 | 423 else: |
| 424 raise NotImplementedError(str(t)) | |
| 425 | |
| 389 | 426 def the_type(self, t, reveil_defined=True): |
| 427 """ Recurse until a 'real' type is found | |
| 428 When reveil_defined is True, defined types are resolved to | |
| 429 their backing types. | |
| 430 """ | |
| 308 | 431 if type(t) is ast.DefinedType: |
| 389 | 432 if reveil_defined: |
| 433 t = self.the_type(t.typ) | |
| 308 | 434 elif type(t) in [ast.Identifier, ast.Member]: |
| 389 | 435 t = self.the_type(self.resolveSymbol(t), reveil_defined) |
| 308 | 436 elif isinstance(t, ast.Type): |
| 307 | 437 pass |
| 438 else: | |
| 439 raise NotImplementedError(str(t)) | |
| 308 | 440 assert isinstance(t, ast.Type) |
| 307 | 441 return t |
| 442 | |
| 389 | 443 def equal_types(self, a, b, byname=False): |
| 444 """ Compare types a and b for structural equavalence. | |
| 445 if byname is True stop on defined types. | |
| 446 """ | |
| 307 | 447 # Recurse into named types: |
| 389 | 448 a = self.the_type(a, not byname) |
| 449 b = self.the_type(b, not byname) | |
| 307 | 450 |
| 389 | 451 # Check types for sanity: |
| 452 self.check_type(a) | |
| 453 self.check_type(b) | |
| 454 | |
| 455 # Do structural equivalence check: | |
| 307 | 456 if type(a) is type(b): |
| 308 | 457 if type(a) is ast.BaseType: |
| 307 | 458 return a.name == b.name |
| 308 | 459 elif type(a) is ast.PointerType: |
| 389 | 460 # If a pointed type is detected, stop structural |
| 461 # equivalence: | |
| 462 return self.equal_types(a.ptype, b.ptype, byname=True) | |
| 308 | 463 elif type(a) is ast.StructureType: |
| 307 | 464 if len(a.mems) != len(b.mems): |
| 465 return False | |
| 389 | 466 return all(self.equal_types(am.typ, bm.typ) for am, bm in |
| 307 | 467 zip(a.mems, b.mems)) |
| 354 | 468 elif type(a) is ast.ArrayType: |
| 389 | 469 return self.equal_types(a.element_type, b.element_type) |
| 470 elif type(a) is ast.DefinedType: | |
| 471 # Try by name in case of defined types: | |
| 472 return a.name == b.name | |
| 307 | 473 else: |
| 474 raise NotImplementedError('{} not implemented'.format(type(a))) | |
| 475 return False | |
| 389 | 476 |
| 477 def check_type(self, t, first=True, byname=False): | |
| 478 """ Determine struct offsets and check for recursiveness by using | |
| 479 mark and sweep algorithm. | |
| 480 The calling function could call this function with first set | |
| 481 to clear the marks. | |
| 482 """ | |
| 483 | |
| 484 # Reset the mark and sweep: | |
| 485 if first: | |
| 486 self.got_types = set() | |
| 487 | |
| 488 # Resolve the type: | |
| 489 t = self.the_type(t, not byname) | |
| 490 | |
| 491 # Check for recursion: | |
| 492 if t in self.got_types: | |
| 493 raise SemanticError('Recursive data type {}'.format(t), None) | |
| 494 | |
| 495 if type(t) is ast.BaseType: | |
| 496 pass | |
| 497 elif type(t) is ast.PointerType: | |
| 498 # If a pointed type is detected, stop structural | |
| 499 # equivalence: | |
| 500 self.check_type(t.ptype, first=False, byname=True) | |
| 501 elif type(t) is ast.StructureType: | |
| 502 self.got_types.add(t) | |
| 503 # Setup offsets of fields. Is this the right place?: | |
| 504 offset = 0 | |
| 505 for struct_member in t.mems: | |
| 506 self.check_type(struct_member.typ, first=False) | |
| 507 struct_member.offset = offset | |
| 508 offset = offset + self.size_of(struct_member.typ) | |
| 509 elif type(t) is ast.ArrayType: | |
| 510 self.check_type(t.element_type, first=False) | |
| 511 elif type(t) is ast.DefinedType: | |
| 512 pass | |
| 513 else: | |
| 514 raise NotImplementedError('{} not implemented'.format(type(t))) |