code.kerkeslager.com Git - fur/blob - transformation.py

   1 import collections
   2
   3 import normalization
   4 import parsing
   5
   6 CIntegerLiteral = collections.namedtuple(
   7     'CIntegerLiteral',
   8     [
   9         'value',
  10     ],
  11 )
  12
  13 CStringLiteral = collections.namedtuple(
  14     'CStringLiteral',
  15     [
  16         'index',
  17         'value',
  18     ],
  19 )
  20
  21 CConstantExpression = collections.namedtuple(
  22     'CConstantExpression',
  23     [
  24         'value'
  25     ],
  26 )
  27
  28 CVariableExpression = collections.namedtuple(
  29     'CVariableExpression',
  30     [
  31         'variable',
  32     ],
  33 )
  34
  35 CSymbolExpression = collections.namedtuple(
  36     'CSymbolExpression',
  37     [
  38         'symbol',
  39         'symbol_list_index',
  40     ],
  41 )
  42
  43 CNegationExpression = collections.namedtuple(
  44     'CNegationExpression',
  45     [
  46         'value',
  47     ],
  48 )
  49
  50 CFunctionCallForFurInfixOperator = collections.namedtuple(
  51     'CFunctionCallForFurInfixOperator',
  52     [
  53         'name',
  54         'left',
  55         'right',
  56     ],
  57 )
  58
  59 CFunctionCallExpression = collections.namedtuple(
  60     'CFunctionCallExpression',
  61     [
  62         'name',
  63         'argument_count',
  64         'argument_items',
  65     ],
  66 )
  67
  68 CSymbolAssignmentStatement = collections.namedtuple(
  69     'CSymbolAssignmentStatement',
  70     [
  71         'target',
  72         'target_symbol_list_index',
  73         'expression',
  74     ],
  75 )
  76
  77 CArrayVariableInitializationStatement = collections.namedtuple(
  78     'CArrayVariableInitializationStatement',
  79     [
  80         'variable',
  81         'items',
  82     ],
  83 )
  84
  85 CVariableInitializationStatement = collections.namedtuple(
  86     'CVariableInitializationStatement',
  87     [
  88         'variable',
  89         'expression',
  90     ],
  91 )
  92
  93 CVariableReassignmentStatement = collections.namedtuple(
  94     'CVariableReassignmentStatement',
  95     [
  96         'variable',
  97         'expression',
  98     ],
  99 )
 100
 101 CExpressionStatement = collections.namedtuple(
 102     'CExpressionStatement',
 103     [
 104         'expression',
 105     ],
 106 )
 107
 108 CIfElseStatement = collections.namedtuple(
 109     'CIfElseStatement',
 110     [
 111         'condition_expression',
 112         'if_statements',
 113         'else_statements',
 114     ],
 115 )
 116
 117 CFunctionDeclaration = collections.namedtuple(
 118     'CFunctionDeclaration',
 119     [
 120         'name',
 121     ],
 122 )
 123
 124 CFunctionDefinition = collections.namedtuple(
 125     'CFunctionDefinition',
 126     [
 127         'name',
 128         'statement_list',
 129     ],
 130 )
 131
 132 CProgram = collections.namedtuple(
 133     'CProgram',
 134     [
 135         'builtin_set',
 136         'function_definition_list',
 137         'operator_declarations',
 138         'statements',
 139         'standard_libraries',
 140         'string_literal_list',
 141         'symbol_list',
 142     ],
 143 )
 144
 145 BUILTINS = {
 146     'false':    [],
 147     'pow':      ['math.h'],
 148     'print':    ['stdio.h'],
 149     'true':     [],
 150 }
 151
 152 def transform_variable_expression(accumulators, expression):
 153     return CVariableExpression(variable=expression.variable)
 154
 155 def transform_string_literal(accumulators, expression):
 156     value = expression.value
 157
 158     try:
 159         index = accumulators.string_literal_list.index(value)
 160     except ValueError:
 161         index = len(accumulators.string_literal_list)
 162         accumulators.string_literal_list.append(value)
 163
 164     return CStringLiteral(index=index, value=value)
 165
 166 def transform_symbol_expression(accumulators, expression):
 167     if expression.value in ['true', 'false']:
 168         return CConstantExpression(value=expression.value)
 169
 170     if expression.value not in accumulators.symbol_list:
 171         symbol_list.append(expression.value)
 172
 173     return CSymbolExpression(
 174         symbol=expression.value,
 175         symbol_list_index=accumulators.symbol_list.index(expression.value),
 176     )
 177
 178 CInfixDeclaration = collections.namedtuple(
 179     'CInfixDeclaration',
 180     [
 181         'name',
 182         'in_type',
 183         'out_type',
 184         'operator',
 185     ],
 186 )
 187
 188 INFIX_OPERATOR_TO_DECLARATION = {
 189     '+':    CInfixDeclaration(name='add', in_type='integer', out_type='integer', operator='+'),
 190     '-':    CInfixDeclaration(name='subtract', in_type='integer', out_type='integer', operator='-'),
 191     '*':    CInfixDeclaration(name='multiply', in_type='integer', out_type='integer', operator='*'),
 192     '//':   CInfixDeclaration(name='integerDivide', in_type='integer', out_type='integer', operator='/'),
 193     '%':    CInfixDeclaration(name='modularDivide', in_type='integer', out_type='integer', operator='%'),
 194     'and':  CInfixDeclaration(name='and', in_type='boolean', out_type='boolean', operator='&&'),
 195     'or':   CInfixDeclaration(name='or', in_type='boolean', out_type='boolean', operator='||'),
 196     '==':   CInfixDeclaration(name='equals', in_type='integer', out_type='boolean', operator='=='),
 197     '!=':   CInfixDeclaration(name='notEquals', in_type='integer', out_type='boolean', operator='!='),
 198     '<=':   CInfixDeclaration(name='lessThanOrEqual', in_type='integer', out_type='boolean', operator='<='),
 199     '>=':   CInfixDeclaration(name='greaterThanOrEqual', in_type='integer', out_type='boolean', operator='>='),
 200     '<':    CInfixDeclaration(name='lessThan', in_type='integer', out_type='boolean', operator='<'),
 201     '>':    CInfixDeclaration(name='greaterThan', in_type='integer', out_type='boolean', operator='>'),
 202 }
 203
 204 def transform_comparison_level_expression(accumulators, expression):
 205     accumulators.operator_set.add(INFIX_OPERATOR_TO_DECLARATION[expression.operator])
 206
 207     # Transform expressions like 1 < 2 < 3 into expressions like 1 < 2 && 2 < 3
 208     if isinstance(expression.left, parsing.FurInfixExpression) and expression.left.order == 'comparison_level':
 209         left = transform_comparison_level_expression(
 210             accumulators,
 211             expression.left
 212         )
 213
 214         middle = left.right
 215
 216         right = transform_expression(
 217             accumulators,
 218             expression.right,
 219         )
 220
 221         # TODO Don't evaluate the middle expression twice
 222         return CFunctionCallForFurInfixOperator(
 223             name='and',
 224             left=left,
 225             right=CFunctionCallForFurInfixOperator(
 226                 name=INFIX_OPERATOR_TO_DECLARATION[expression.operator].name,
 227                 left=middle,
 228                 right=right,
 229             ),
 230         )
 231
 232     return CFunctionCallForFurInfixOperator(
 233         name=INFIX_OPERATOR_TO_DECLARATION[expression.operator].name,
 234         left=transform_expression(accumulators, expression.left),
 235         right=transform_expression(accumulators, expression.right),
 236     )
 237
 238 def transform_infix_expression(accumulators, expression):
 239     if expression.order == 'comparison_level':
 240         return transform_comparison_level_expression(accumulators, expression)
 241
 242     accumulators.operator_set.add(INFIX_OPERATOR_TO_DECLARATION[expression.operator])
 243
 244     return CFunctionCallForFurInfixOperator(
 245         name=INFIX_OPERATOR_TO_DECLARATION[expression.operator].name,
 246         left=transform_expression(accumulators, expression.left),
 247         right=transform_expression(accumulators, expression.right),
 248     )
 249
 250 def transform_integer_literal_expression(accumulators, expression):
 251     return CIntegerLiteral(value=expression.value)
 252
 253 def transform_parenthesized_expression(accumulators, expression):
 254     # Parentheses can be removed because everything in the C output is explicitly parenthesized
 255     return transform_expression(accumulators, expression.internal)
 256
 257 def transform_negation_expression(accumulators, expression):
 258     return CNegationExpression(
 259         value=transform_expression(accumulators, expression.internal_expression),
 260     )
 261
 262 def transform_expression(accumulators, expression):
 263     # TODO Clean up handlers for parsing expressions
 264     return {
 265         parsing.FurFunctionCallExpression: transform_function_call_expression,
 266         parsing.FurInfixExpression: transform_infix_expression,
 267         parsing.FurIntegerLiteralExpression: transform_integer_literal_expression,
 268         parsing.FurNegationExpression: transform_negation_expression,
 269         parsing.FurParenthesizedExpression: transform_parenthesized_expression,
 270         parsing.FurStringLiteralExpression: transform_string_literal,
 271         parsing.FurSymbolExpression: transform_symbol_expression,
 272         normalization.NormalFunctionCallExpression: transform_function_call_expression,
 273         normalization.NormalInfixExpression: transform_infix_expression,
 274         normalization.NormalNegationExpression: transform_negation_expression,
 275         normalization.NormalVariableExpression: transform_variable_expression,
 276     }[type(expression)](accumulators, expression)
 277
 278 def transform_symbol_assignment_statement(accumulators, assignment_statement):
 279     # TODO Check that target is not a builtin
 280     if assignment_statement.target not in accumulators.symbol_list:
 281         accumulators.symbol_list.append(assignment_statement.target)
 282
 283     return CSymbolAssignmentStatement(
 284         target=assignment_statement.target,
 285         target_symbol_list_index=accumulators.symbol_list.index(assignment_statement.target),
 286         expression=transform_expression(
 287             accumulators,
 288             assignment_statement.expression,
 289         ),
 290     )
 291
 292 def transform_function_call_expression(accumulators, function_call):
 293     if function_call.function.value in BUILTINS.keys():
 294         # TODO Check that the builtin is actually callable
 295         accumulators.builtin_set.add(function_call.function.value)
 296
 297     # TODO Use the symbol from SYMBOL LIST
 298     return CFunctionCallExpression(
 299         name=function_call.function.value,
 300         argument_count=function_call.argument_count,
 301         argument_items=transform_expression(accumulators, function_call.argument_items),
 302     )
 303
 304 def transform_expression_statement(accumulators, statement):
 305     # TODO At some point we can verify that all expression types are supported and just call transform_expression
 306     expression = {
 307         parsing.FurFunctionCallExpression: transform_function_call_expression,
 308         parsing.FurInfixExpression: transform_expression,
 309         parsing.FurIntegerLiteralExpression: transform_expression,
 310         parsing.FurSymbolExpression: transform_expression,
 311         normalization.NormalFunctionCallExpression: transform_function_call_expression,
 312         normalization.NormalVariableExpression: transform_expression,
 313     }[type(statement.expression)](accumulators, statement.expression)
 314
 315     return CExpressionStatement(
 316         expression=expression,
 317     )
 318
 319 def transform_if_else_statement(accumulators, statement):
 320     return CIfElseStatement(
 321         condition_expression=transform_expression(accumulators, statement.condition_expression),
 322         if_statements=tuple(transform_statement(accumulators, s) for s in statement.if_statements),
 323         else_statements=tuple(transform_statement(accumulators, s) for s in statement.else_statements),
 324     )
 325
 326 def transform_array_variable_initialization_statement(accumulators, statement):
 327     return CArrayVariableInitializationStatement(
 328         variable=statement.variable,
 329         items=tuple(transform_expression(accumulators, i) for i in statement.items),
 330     )
 331
 332 def transform_variable_initialization_statement(accumulators, statement):
 333     return CVariableInitializationStatement(
 334         variable=statement.variable,
 335         expression=transform_expression(accumulators, statement.expression),
 336     )
 337
 338 def transform_variable_reassignment_statement(accumulators, statement):
 339     return CVariableReassignmentStatement(
 340         variable=statement.variable,
 341         expression=transform_expression(accumulators, statement.expression),
 342     )
 343
 344 def transform_function_definition_statement(accumulators, statement):
 345     # TODO Allow defining the same function in different contexts
 346     if any(fd.name == statement.name for fd in accumulators.function_definition_list):
 347         raise Exception('A function with name "{}" already exists'.format(statement.name))
 348
 349     accumulators.function_definition_list.append(CFunctionDefinition(
 350         name=statement.name,
 351         statement_list=tuple(transform_statement(accumulators, s) for s in statement.statement_list)
 352     ))
 353
 354     return CFunctionDeclaration(name=statement.name)
 355
 356 def transform_statement(accumulators, statement):
 357     return {
 358         parsing.FurAssignmentStatement: transform_symbol_assignment_statement,
 359         parsing.FurExpressionStatement: transform_expression_statement,
 360         normalization.NormalArrayVariableInitializationStatement: transform_array_variable_initialization_statement,
 361         normalization.NormalExpressionStatement: transform_expression_statement,
 362         normalization.NormalFunctionDefinitionStatement: transform_function_definition_statement,
 363         normalization.NormalIfElseStatement: transform_if_else_statement,
 364         normalization.NormalVariableInitializationStatement: transform_variable_initialization_statement,
 365         normalization.NormalVariableReassignmentStatement: transform_variable_reassignment_statement,
 366     }[type(statement)](accumulators, statement)
 367
 368
 369 Accumulators = collections.namedtuple(
 370     'Accumulators',
 371     [
 372         'builtin_set',
 373         'function_definition_list',
 374         'operator_set',
 375         'symbol_list',
 376         'string_literal_list',
 377     ],
 378 )
 379
 380 def transform(program):
 381     accumulators = Accumulators(
 382         builtin_set=set(),
 383         function_definition_list=[],
 384         operator_set=set(),
 385         symbol_list=[],
 386         string_literal_list=[],
 387     )
 388
 389     statement_list = [
 390         transform_statement(accumulators, statement) for statement in program.statement_list
 391     ]
 392
 393     standard_library_set = set()
 394     for builtin in accumulators.builtin_set:
 395         for standard_library in BUILTINS[builtin]:
 396             standard_library_set.add(standard_library)
 397
 398     return CProgram(
 399         builtin_set=accumulators.builtin_set,
 400         function_definition_list=accumulators.function_definition_list,
 401         operator_declarations=tuple(sorted(accumulators.operator_set)),
 402         statements=statement_list,
 403         standard_libraries=standard_library_set,
 404         string_literal_list=accumulators.string_literal_list,
 405         symbol_list=accumulators.symbol_list,
 406     )
 407
 408
 409 if __name__ == '__main__':
 410     import unittest
 411
 412     unittest.main()