isa_parser.py revision 2632:1bb2f91485ea
1# Copyright (c) 2003-2005 The Regents of The University of Michigan 2# All rights reserved. 3# 4# Redistribution and use in source and binary forms, with or without 5# modification, are permitted provided that the following conditions are 6# met: redistributions of source code must retain the above copyright 7# notice, this list of conditions and the following disclaimer; 8# redistributions in binary form must reproduce the above copyright 9# notice, this list of conditions and the following disclaimer in the 10# documentation and/or other materials provided with the distribution; 11# neither the name of the copyright holders nor the names of its 12# contributors may be used to endorse or promote products derived from 13# this software without specific prior written permission. 14# 15# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 16# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 17# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 18# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 19# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 20# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 21# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 22# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 23# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 24# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 25# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 26 27import os 28import sys 29import re 30import string 31import traceback 32# get type names 33from types import * 34 35# Prepend the directory where the PLY lex & yacc modules are found 36# to the search path. Assumes we're compiling in a subdirectory 37# of 'build' in the current tree. 38sys.path[0:0] = [os.environ['M5_PLY']] 39 40import lex 41import yacc 42 43##################################################################### 44# 45# Lexer 46# 47# The PLY lexer module takes two things as input: 48# - A list of token names (the string list 'tokens') 49# - A regular expression describing a match for each token. The 50# regexp for token FOO can be provided in two ways: 51# - as a string variable named t_FOO 52# - as the doc string for a function named t_FOO. In this case, 53# the function is also executed, allowing an action to be 54# associated with each token match. 55# 56##################################################################### 57 58# Reserved words. These are listed separately as they are matched 59# using the same regexp as generic IDs, but distinguished in the 60# t_ID() function. The PLY documentation suggests this approach. 61reserved = ( 62 'BITFIELD', 'DECODE', 'DECODER', 'DEFAULT', 'DEF', 'EXEC', 'FORMAT', 63 'HEADER', 'LET', 'NAMESPACE', 'OPERAND_TYPES', 'OPERANDS', 64 'OUTPUT', 'SIGNED', 'TEMPLATE' 65 ) 66 67# List of tokens. The lex module requires this. 68tokens = reserved + ( 69 # identifier 70 'ID', 71 72 # integer literal 73 'INTLIT', 74 75 # string literal 76 'STRLIT', 77 78 # code literal 79 'CODELIT', 80 81 # ( ) [ ] { } < > , ; : :: * 82 'LPAREN', 'RPAREN', 83 'LBRACKET', 'RBRACKET', 84 'LBRACE', 'RBRACE', 85 'LESS', 'GREATER', 'EQUALS', 86 'COMMA', 'SEMI', 'COLON', 'DBLCOLON', 87 'ASTERISK', 88 89 # C preprocessor directives 90 'CPPDIRECTIVE' 91 92# The following are matched but never returned. commented out to 93# suppress PLY warning 94 # newfile directive 95# 'NEWFILE', 96 97 # endfile directive 98# 'ENDFILE' 99) 100 101# Regular expressions for token matching 102t_LPAREN = r'\(' 103t_RPAREN = r'\)' 104t_LBRACKET = r'\[' 105t_RBRACKET = r'\]' 106t_LBRACE = r'\{' 107t_RBRACE = r'\}' 108t_LESS = r'\<' 109t_GREATER = r'\>' 110t_EQUALS = r'=' 111t_COMMA = r',' 112t_SEMI = r';' 113t_COLON = r':' 114t_DBLCOLON = r'::' 115t_ASTERISK = r'\*' 116 117# Identifiers and reserved words 118reserved_map = { } 119for r in reserved: 120 reserved_map[r.lower()] = r 121 122def t_ID(t): 123 r'[A-Za-z_]\w*' 124 t.type = reserved_map.get(t.value,'ID') 125 return t 126 127# Integer literal 128def t_INTLIT(t): 129 r'(0x[\da-fA-F]+)|\d+' 130 try: 131 t.value = int(t.value,0) 132 except ValueError: 133 error(t.lineno, 'Integer value "%s" too large' % t.value) 134 t.value = 0 135 return t 136 137# String literal. Note that these use only single quotes, and 138# can span multiple lines. 139def t_STRLIT(t): 140 r"(?m)'([^'])+'" 141 # strip off quotes 142 t.value = t.value[1:-1] 143 t.lineno += t.value.count('\n') 144 return t 145 146 147# "Code literal"... like a string literal, but delimiters are 148# '{{' and '}}' so they get formatted nicely under emacs c-mode 149def t_CODELIT(t): 150 r"(?m)\{\{([^\}]|}(?!\}))+\}\}" 151 # strip off {{ & }} 152 t.value = t.value[2:-2] 153 t.lineno += t.value.count('\n') 154 return t 155 156def t_CPPDIRECTIVE(t): 157 r'^\#[^\#].*\n' 158 t.lineno += t.value.count('\n') 159 return t 160 161def t_NEWFILE(t): 162 r'^\#\#newfile\s+"[\w/.-]*"' 163 fileNameStack.push((t.value[11:-1], t.lineno)) 164 t.lineno = 0 165 166def t_ENDFILE(t): 167 r'^\#\#endfile' 168 (old_filename, t.lineno) = fileNameStack.pop() 169 170# 171# The functions t_NEWLINE, t_ignore, and t_error are 172# special for the lex module. 173# 174 175# Newlines 176def t_NEWLINE(t): 177 r'\n+' 178 t.lineno += t.value.count('\n') 179 180# Comments 181def t_comment(t): 182 r'//.*' 183 184# Completely ignored characters 185t_ignore = ' \t\x0c' 186 187# Error handler 188def t_error(t): 189 error(t.lineno, "illegal character '%s'" % t.value[0]) 190 t.skip(1) 191 192# Build the lexer 193lex.lex() 194 195##################################################################### 196# 197# Parser 198# 199# Every function whose name starts with 'p_' defines a grammar rule. 200# The rule is encoded in the function's doc string, while the 201# function body provides the action taken when the rule is matched. 202# The argument to each function is a list of the values of the 203# rule's symbols: t[0] for the LHS, and t[1..n] for the symbols 204# on the RHS. For tokens, the value is copied from the t.value 205# attribute provided by the lexer. For non-terminals, the value 206# is assigned by the producing rule; i.e., the job of the grammar 207# rule function is to set the value for the non-terminal on the LHS 208# (by assigning to t[0]). 209##################################################################### 210 211# The LHS of the first grammar rule is used as the start symbol 212# (in this case, 'specification'). Note that this rule enforces 213# that there will be exactly one namespace declaration, with 0 or more 214# global defs/decls before and after it. The defs & decls before 215# the namespace decl will be outside the namespace; those after 216# will be inside. The decoder function is always inside the namespace. 217def p_specification(t): 218 'specification : opt_defs_and_outputs name_decl opt_defs_and_outputs decode_block' 219 global_code = t[1] 220 isa_name = t[2] 221 namespace = isa_name + "Inst" 222 # wrap the decode block as a function definition 223 t[4].wrap_decode_block(''' 224StaticInstPtr 225%(isa_name)s::decodeInst(%(isa_name)s::ExtMachInst machInst) 226{ 227 using namespace %(namespace)s; 228''' % vars(), '}') 229 # both the latter output blocks and the decode block are in the namespace 230 namespace_code = t[3] + t[4] 231 # pass it all back to the caller of yacc.parse() 232 t[0] = (isa_name, namespace, global_code, namespace_code) 233 234# ISA name declaration looks like "namespace <foo>;" 235def p_name_decl(t): 236 'name_decl : NAMESPACE ID SEMI' 237 t[0] = t[2] 238 239# 'opt_defs_and_outputs' is a possibly empty sequence of 240# def and/or output statements. 241def p_opt_defs_and_outputs_0(t): 242 'opt_defs_and_outputs : empty' 243 t[0] = GenCode() 244 245def p_opt_defs_and_outputs_1(t): 246 'opt_defs_and_outputs : defs_and_outputs' 247 t[0] = t[1] 248 249def p_defs_and_outputs_0(t): 250 'defs_and_outputs : def_or_output' 251 t[0] = t[1] 252 253def p_defs_and_outputs_1(t): 254 'defs_and_outputs : defs_and_outputs def_or_output' 255 t[0] = t[1] + t[2] 256 257# The list of possible definition/output statements. 258def p_def_or_output(t): 259 '''def_or_output : def_format 260 | def_bitfield 261 | def_template 262 | def_operand_types 263 | def_operands 264 | output_header 265 | output_decoder 266 | output_exec 267 | global_let''' 268 t[0] = t[1] 269 270# Output blocks 'output <foo> {{...}}' (C++ code blocks) are copied 271# directly to the appropriate output section. 272 273 274# Protect any non-dict-substitution '%'s in a format string 275# (i.e. those not followed by '(') 276def protect_non_subst_percents(s): 277 return re.sub(r'%(?!\()', '%%', s) 278 279# Massage output block by substituting in template definitions and bit 280# operators. We handle '%'s embedded in the string that don't 281# indicate template substitutions (or CPU-specific symbols, which get 282# handled in GenCode) by doubling them first so that the format 283# operation will reduce them back to single '%'s. 284def process_output(s): 285 s = protect_non_subst_percents(s) 286 # protects cpu-specific symbols too 287 s = protect_cpu_symbols(s) 288 return substBitOps(s % templateMap) 289 290def p_output_header(t): 291 'output_header : OUTPUT HEADER CODELIT SEMI' 292 t[0] = GenCode(header_output = process_output(t[3])) 293 294def p_output_decoder(t): 295 'output_decoder : OUTPUT DECODER CODELIT SEMI' 296 t[0] = GenCode(decoder_output = process_output(t[3])) 297 298def p_output_exec(t): 299 'output_exec : OUTPUT EXEC CODELIT SEMI' 300 t[0] = GenCode(exec_output = process_output(t[3])) 301 302# global let blocks 'let {{...}}' (Python code blocks) are executed 303# directly when seen. Note that these execute in a special variable 304# context 'exportContext' to prevent the code from polluting this 305# script's namespace. 306def p_global_let(t): 307 'global_let : LET CODELIT SEMI' 308 updateExportContext() 309 try: 310 exec fixPythonIndentation(t[2]) in exportContext 311 except Exception, exc: 312 error(t.lineno(1), 313 'error: %s in global let block "%s".' % (exc, t[2])) 314 t[0] = GenCode() # contributes nothing to the output C++ file 315 316# Define the mapping from operand type extensions to C++ types and bit 317# widths (stored in operandTypeMap). 318def p_def_operand_types(t): 319 'def_operand_types : DEF OPERAND_TYPES CODELIT SEMI' 320 try: 321 userDict = eval('{' + t[3] + '}') 322 except Exception, exc: 323 error(t.lineno(1), 324 'error: %s in def operand_types block "%s".' % (exc, t[3])) 325 buildOperandTypeMap(userDict, t.lineno(1)) 326 t[0] = GenCode() # contributes nothing to the output C++ file 327 328# Define the mapping from operand names to operand classes and other 329# traits. Stored in operandNameMap. 330def p_def_operands(t): 331 'def_operands : DEF OPERANDS CODELIT SEMI' 332 if not globals().has_key('operandTypeMap'): 333 error(t.lineno(1), 334 'error: operand types must be defined before operands') 335 try: 336 userDict = eval('{' + t[3] + '}') 337 except Exception, exc: 338 error(t.lineno(1), 339 'error: %s in def operands block "%s".' % (exc, t[3])) 340 buildOperandNameMap(userDict, t.lineno(1)) 341 t[0] = GenCode() # contributes nothing to the output C++ file 342 343# A bitfield definition looks like: 344# 'def [signed] bitfield <ID> [<first>:<last>]' 345# This generates a preprocessor macro in the output file. 346def p_def_bitfield_0(t): 347 'def_bitfield : DEF opt_signed BITFIELD ID LESS INTLIT COLON INTLIT GREATER SEMI' 348 expr = 'bits(machInst, %2d, %2d)' % (t[6], t[8]) 349 if (t[2] == 'signed'): 350 expr = 'sext<%d>(%s)' % (t[6] - t[8] + 1, expr) 351 hash_define = '#undef %s\n#define %s\t%s\n' % (t[4], t[4], expr) 352 t[0] = GenCode(header_output = hash_define) 353 354# alternate form for single bit: 'def [signed] bitfield <ID> [<bit>]' 355def p_def_bitfield_1(t): 356 'def_bitfield : DEF opt_signed BITFIELD ID LESS INTLIT GREATER SEMI' 357 expr = 'bits(machInst, %2d, %2d)' % (t[6], t[6]) 358 if (t[2] == 'signed'): 359 expr = 'sext<%d>(%s)' % (1, expr) 360 hash_define = '#undef %s\n#define %s\t%s\n' % (t[4], t[4], expr) 361 t[0] = GenCode(header_output = hash_define) 362 363def p_opt_signed_0(t): 364 'opt_signed : SIGNED' 365 t[0] = t[1] 366 367def p_opt_signed_1(t): 368 'opt_signed : empty' 369 t[0] = '' 370 371# Global map variable to hold templates 372templateMap = {} 373 374def p_def_template(t): 375 'def_template : DEF TEMPLATE ID CODELIT SEMI' 376 templateMap[t[3]] = Template(t[4]) 377 t[0] = GenCode() 378 379# An instruction format definition looks like 380# "def format <fmt>(<params>) {{...}};" 381def p_def_format(t): 382 'def_format : DEF FORMAT ID LPAREN param_list RPAREN CODELIT SEMI' 383 (id, params, code) = (t[3], t[5], t[7]) 384 defFormat(id, params, code, t.lineno(1)) 385 t[0] = GenCode() 386 387# The formal parameter list for an instruction format is a possibly 388# empty list of comma-separated parameters. Positional (standard, 389# non-keyword) parameters must come first, followed by keyword 390# parameters, followed by a '*foo' parameter that gets excess 391# positional arguments (as in Python). Each of these three parameter 392# categories is optional. 393# 394# Note that we do not support the '**foo' parameter for collecting 395# otherwise undefined keyword args. Otherwise the parameter list is 396# (I believe) identical to what is supported in Python. 397# 398# The param list generates a tuple, where the first element is a list of 399# the positional params and the second element is a dict containing the 400# keyword params. 401def p_param_list_0(t): 402 'param_list : positional_param_list COMMA nonpositional_param_list' 403 t[0] = t[1] + t[3] 404 405def p_param_list_1(t): 406 '''param_list : positional_param_list 407 | nonpositional_param_list''' 408 t[0] = t[1] 409 410def p_positional_param_list_0(t): 411 'positional_param_list : empty' 412 t[0] = [] 413 414def p_positional_param_list_1(t): 415 'positional_param_list : ID' 416 t[0] = [t[1]] 417 418def p_positional_param_list_2(t): 419 'positional_param_list : positional_param_list COMMA ID' 420 t[0] = t[1] + [t[3]] 421 422def p_nonpositional_param_list_0(t): 423 'nonpositional_param_list : keyword_param_list COMMA excess_args_param' 424 t[0] = t[1] + t[3] 425 426def p_nonpositional_param_list_1(t): 427 '''nonpositional_param_list : keyword_param_list 428 | excess_args_param''' 429 t[0] = t[1] 430 431def p_keyword_param_list_0(t): 432 'keyword_param_list : keyword_param' 433 t[0] = [t[1]] 434 435def p_keyword_param_list_1(t): 436 'keyword_param_list : keyword_param_list COMMA keyword_param' 437 t[0] = t[1] + [t[3]] 438 439def p_keyword_param(t): 440 'keyword_param : ID EQUALS expr' 441 t[0] = t[1] + ' = ' + t[3].__repr__() 442 443def p_excess_args_param(t): 444 'excess_args_param : ASTERISK ID' 445 # Just concatenate them: '*ID'. Wrap in list to be consistent 446 # with positional_param_list and keyword_param_list. 447 t[0] = [t[1] + t[2]] 448 449# End of format definition-related rules. 450############## 451 452# 453# A decode block looks like: 454# decode <field1> [, <field2>]* [default <inst>] { ... } 455# 456def p_decode_block(t): 457 'decode_block : DECODE ID opt_default LBRACE decode_stmt_list RBRACE' 458 default_defaults = defaultStack.pop() 459 codeObj = t[5] 460 # use the "default defaults" only if there was no explicit 461 # default statement in decode_stmt_list 462 if not codeObj.has_decode_default: 463 codeObj += default_defaults 464 codeObj.wrap_decode_block('switch (%s) {\n' % t[2], '}\n') 465 t[0] = codeObj 466 467# The opt_default statement serves only to push the "default defaults" 468# onto defaultStack. This value will be used by nested decode blocks, 469# and used and popped off when the current decode_block is processed 470# (in p_decode_block() above). 471def p_opt_default_0(t): 472 'opt_default : empty' 473 # no default specified: reuse the one currently at the top of the stack 474 defaultStack.push(defaultStack.top()) 475 # no meaningful value returned 476 t[0] = None 477 478def p_opt_default_1(t): 479 'opt_default : DEFAULT inst' 480 # push the new default 481 codeObj = t[2] 482 codeObj.wrap_decode_block('\ndefault:\n', 'break;\n') 483 defaultStack.push(codeObj) 484 # no meaningful value returned 485 t[0] = None 486 487def p_decode_stmt_list_0(t): 488 'decode_stmt_list : decode_stmt' 489 t[0] = t[1] 490 491def p_decode_stmt_list_1(t): 492 'decode_stmt_list : decode_stmt decode_stmt_list' 493 if (t[1].has_decode_default and t[2].has_decode_default): 494 error(t.lineno(1), 'Two default cases in decode block') 495 t[0] = t[1] + t[2] 496 497# 498# Decode statement rules 499# 500# There are four types of statements allowed in a decode block: 501# 1. Format blocks 'format <foo> { ... }' 502# 2. Nested decode blocks 503# 3. Instruction definitions. 504# 4. C preprocessor directives. 505 506 507# Preprocessor directives found in a decode statement list are passed 508# through to the output, replicated to all of the output code 509# streams. This works well for ifdefs, so we can ifdef out both the 510# declarations and the decode cases generated by an instruction 511# definition. Handling them as part of the grammar makes it easy to 512# keep them in the right place with respect to the code generated by 513# the other statements. 514def p_decode_stmt_cpp(t): 515 'decode_stmt : CPPDIRECTIVE' 516 t[0] = GenCode(t[1], t[1], t[1], t[1]) 517 518# A format block 'format <foo> { ... }' sets the default instruction 519# format used to handle instruction definitions inside the block. 520# This format can be overridden by using an explicit format on the 521# instruction definition or with a nested format block. 522def p_decode_stmt_format(t): 523 'decode_stmt : FORMAT push_format_id LBRACE decode_stmt_list RBRACE' 524 # The format will be pushed on the stack when 'push_format_id' is 525 # processed (see below). Once the parser has recognized the full 526 # production (though the right brace), we're done with the format, 527 # so now we can pop it. 528 formatStack.pop() 529 t[0] = t[4] 530 531# This rule exists so we can set the current format (& push the stack) 532# when we recognize the format name part of the format block. 533def p_push_format_id(t): 534 'push_format_id : ID' 535 try: 536 formatStack.push(formatMap[t[1]]) 537 t[0] = ('', '// format %s' % t[1]) 538 except KeyError: 539 error(t.lineno(1), 'instruction format "%s" not defined.' % t[1]) 540 541# Nested decode block: if the value of the current field matches the 542# specified constant, do a nested decode on some other field. 543def p_decode_stmt_decode(t): 544 'decode_stmt : case_label COLON decode_block' 545 label = t[1] 546 codeObj = t[3] 547 # just wrap the decoding code from the block as a case in the 548 # outer switch statement. 549 codeObj.wrap_decode_block('\n%s:\n' % label) 550 codeObj.has_decode_default = (label == 'default') 551 t[0] = codeObj 552 553# Instruction definition (finally!). 554def p_decode_stmt_inst(t): 555 'decode_stmt : case_label COLON inst SEMI' 556 label = t[1] 557 codeObj = t[3] 558 codeObj.wrap_decode_block('\n%s:' % label, 'break;\n') 559 codeObj.has_decode_default = (label == 'default') 560 t[0] = codeObj 561 562# The case label is either a list of one or more constants or 'default' 563def p_case_label_0(t): 564 'case_label : intlit_list' 565 t[0] = ': '.join(map(lambda a: 'case %#x' % a, t[1])) 566 567def p_case_label_1(t): 568 'case_label : DEFAULT' 569 t[0] = 'default' 570 571# 572# The constant list for a decode case label must be non-empty, but may have 573# one or more comma-separated integer literals in it. 574# 575def p_intlit_list_0(t): 576 'intlit_list : INTLIT' 577 t[0] = [t[1]] 578 579def p_intlit_list_1(t): 580 'intlit_list : intlit_list COMMA INTLIT' 581 t[0] = t[1] 582 t[0].append(t[3]) 583 584# Define an instruction using the current instruction format (specified 585# by an enclosing format block). 586# "<mnemonic>(<args>)" 587def p_inst_0(t): 588 'inst : ID LPAREN arg_list RPAREN' 589 # Pass the ID and arg list to the current format class to deal with. 590 currentFormat = formatStack.top() 591 codeObj = currentFormat.defineInst(t[1], t[3], t.lineno(1)) 592 args = ','.join(map(str, t[3])) 593 args = re.sub('(?m)^', '//', args) 594 args = re.sub('^//', '', args) 595 comment = '\n// %s::%s(%s)\n' % (currentFormat.id, t[1], args) 596 codeObj.prepend_all(comment) 597 t[0] = codeObj 598 599# Define an instruction using an explicitly specified format: 600# "<fmt>::<mnemonic>(<args>)" 601def p_inst_1(t): 602 'inst : ID DBLCOLON ID LPAREN arg_list RPAREN' 603 try: 604 format = formatMap[t[1]] 605 except KeyError: 606 error(t.lineno(1), 'instruction format "%s" not defined.' % t[1]) 607 codeObj = format.defineInst(t[3], t[5], t.lineno(1)) 608 comment = '\n// %s::%s(%s)\n' % (t[1], t[3], t[5]) 609 codeObj.prepend_all(comment) 610 t[0] = codeObj 611 612# The arg list generates a tuple, where the first element is a list of 613# the positional args and the second element is a dict containing the 614# keyword args. 615def p_arg_list_0(t): 616 'arg_list : positional_arg_list COMMA keyword_arg_list' 617 t[0] = ( t[1], t[3] ) 618 619def p_arg_list_1(t): 620 'arg_list : positional_arg_list' 621 t[0] = ( t[1], {} ) 622 623def p_arg_list_2(t): 624 'arg_list : keyword_arg_list' 625 t[0] = ( [], t[1] ) 626 627def p_positional_arg_list_0(t): 628 'positional_arg_list : empty' 629 t[0] = [] 630 631def p_positional_arg_list_1(t): 632 'positional_arg_list : expr' 633 t[0] = [t[1]] 634 635def p_positional_arg_list_2(t): 636 'positional_arg_list : positional_arg_list COMMA expr' 637 t[0] = t[1] + [t[3]] 638 639def p_keyword_arg_list_0(t): 640 'keyword_arg_list : keyword_arg' 641 t[0] = t[1] 642 643def p_keyword_arg_list_1(t): 644 'keyword_arg_list : keyword_arg_list COMMA keyword_arg' 645 t[0] = t[1] 646 t[0].update(t[3]) 647 648def p_keyword_arg(t): 649 'keyword_arg : ID EQUALS expr' 650 t[0] = { t[1] : t[3] } 651 652# 653# Basic expressions. These constitute the argument values of 654# "function calls" (i.e. instruction definitions in the decode block) 655# and default values for formal parameters of format functions. 656# 657# Right now, these are either strings, integers, or (recursively) 658# lists of exprs (using Python square-bracket list syntax). Note that 659# bare identifiers are trated as string constants here (since there 660# isn't really a variable namespace to refer to). 661# 662def p_expr_0(t): 663 '''expr : ID 664 | INTLIT 665 | STRLIT 666 | CODELIT''' 667 t[0] = t[1] 668 669def p_expr_1(t): 670 '''expr : LBRACKET list_expr RBRACKET''' 671 t[0] = t[2] 672 673def p_list_expr_0(t): 674 'list_expr : expr' 675 t[0] = [t[1]] 676 677def p_list_expr_1(t): 678 'list_expr : list_expr COMMA expr' 679 t[0] = t[1] + [t[3]] 680 681def p_list_expr_2(t): 682 'list_expr : empty' 683 t[0] = [] 684 685# 686# Empty production... use in other rules for readability. 687# 688def p_empty(t): 689 'empty :' 690 pass 691 692# Parse error handler. Note that the argument here is the offending 693# *token*, not a grammar symbol (hence the need to use t.value) 694def p_error(t): 695 if t: 696 error(t.lineno, "syntax error at '%s'" % t.value) 697 else: 698 error(0, "unknown syntax error", True) 699 700# END OF GRAMMAR RULES 701# 702# Now build the parser. 703yacc.yacc() 704 705 706##################################################################### 707# 708# Support Classes 709# 710##################################################################### 711 712# Expand template with CPU-specific references into a dictionary with 713# an entry for each CPU model name. The entry key is the model name 714# and the corresponding value is the template with the CPU-specific 715# refs substituted for that model. 716def expand_cpu_symbols_to_dict(template): 717 # Protect '%'s that don't go with CPU-specific terms 718 t = re.sub(r'%(?!\(CPU_)', '%%', template) 719 result = {} 720 for cpu in cpu_models: 721 result[cpu.name] = t % cpu.strings 722 return result 723 724# *If* the template has CPU-specific references, return a single 725# string containing a copy of the template for each CPU model with the 726# corresponding values substituted in. If the template has no 727# CPU-specific references, it is returned unmodified. 728def expand_cpu_symbols_to_string(template): 729 if template.find('%(CPU_') != -1: 730 return reduce(lambda x,y: x+y, 731 expand_cpu_symbols_to_dict(template).values()) 732 else: 733 return template 734 735# Protect CPU-specific references by doubling the corresponding '%'s 736# (in preparation for substituting a different set of references into 737# the template). 738def protect_cpu_symbols(template): 739 return re.sub(r'%(?=\(CPU_)', '%%', template) 740 741############### 742# GenCode class 743# 744# The GenCode class encapsulates generated code destined for various 745# output files. The header_output and decoder_output attributes are 746# strings containing code destined for decoder.hh and decoder.cc 747# respectively. The decode_block attribute contains code to be 748# incorporated in the decode function itself (that will also end up in 749# decoder.cc). The exec_output attribute is a dictionary with a key 750# for each CPU model name; the value associated with a particular key 751# is the string of code for that CPU model's exec.cc file. The 752# has_decode_default attribute is used in the decode block to allow 753# explicit default clauses to override default default clauses. 754 755class GenCode: 756 # Constructor. At this point we substitute out all CPU-specific 757 # symbols. For the exec output, these go into the per-model 758 # dictionary. For all other output types they get collapsed into 759 # a single string. 760 def __init__(self, 761 header_output = '', decoder_output = '', exec_output = '', 762 decode_block = '', has_decode_default = False): 763 self.header_output = expand_cpu_symbols_to_string(header_output) 764 self.decoder_output = expand_cpu_symbols_to_string(decoder_output) 765 if isinstance(exec_output, dict): 766 self.exec_output = exec_output 767 elif isinstance(exec_output, str): 768 # If the exec_output arg is a single string, we replicate 769 # it for each of the CPU models, substituting and 770 # %(CPU_foo)s params appropriately. 771 self.exec_output = expand_cpu_symbols_to_dict(exec_output) 772 self.decode_block = expand_cpu_symbols_to_string(decode_block) 773 self.has_decode_default = has_decode_default 774 775 # Override '+' operator: generate a new GenCode object that 776 # concatenates all the individual strings in the operands. 777 def __add__(self, other): 778 exec_output = {} 779 for cpu in cpu_models: 780 n = cpu.name 781 exec_output[n] = self.exec_output[n] + other.exec_output[n] 782 return GenCode(self.header_output + other.header_output, 783 self.decoder_output + other.decoder_output, 784 exec_output, 785 self.decode_block + other.decode_block, 786 self.has_decode_default or other.has_decode_default) 787 788 # Prepend a string (typically a comment) to all the strings. 789 def prepend_all(self, pre): 790 self.header_output = pre + self.header_output 791 self.decoder_output = pre + self.decoder_output 792 self.decode_block = pre + self.decode_block 793 for cpu in cpu_models: 794 self.exec_output[cpu.name] = pre + self.exec_output[cpu.name] 795 796 # Wrap the decode block in a pair of strings (e.g., 'case foo:' 797 # and 'break;'). Used to build the big nested switch statement. 798 def wrap_decode_block(self, pre, post = ''): 799 self.decode_block = pre + indent(self.decode_block) + post 800 801################ 802# Format object. 803# 804# A format object encapsulates an instruction format. It must provide 805# a defineInst() method that generates the code for an instruction 806# definition. 807 808exportContextSymbols = ('InstObjParams', 'CodeBlock', 809 'makeList', 're', 'string') 810 811exportContext = {} 812 813def updateExportContext(): 814 exportContext.update(exportDict(*exportContextSymbols)) 815 exportContext.update(templateMap) 816 817def exportDict(*symNames): 818 return dict([(s, eval(s)) for s in symNames]) 819 820 821class Format: 822 def __init__(self, id, params, code): 823 # constructor: just save away arguments 824 self.id = id 825 self.params = params 826 label = 'def format ' + id 827 self.user_code = compile(fixPythonIndentation(code), label, 'exec') 828 param_list = string.join(params, ", ") 829 f = '''def defInst(_code, _context, %s): 830 my_locals = vars().copy() 831 exec _code in _context, my_locals 832 return my_locals\n''' % param_list 833 c = compile(f, label + ' wrapper', 'exec') 834 exec c 835 self.func = defInst 836 837 def defineInst(self, name, args, lineno): 838 context = {} 839 updateExportContext() 840 context.update(exportContext) 841 context.update({ 'name': name, 'Name': string.capitalize(name) }) 842 try: 843 vars = self.func(self.user_code, context, *args[0], **args[1]) 844 except Exception, exc: 845 error(lineno, 'error defining "%s": %s.' % (name, exc)) 846 for k in vars.keys(): 847 if k not in ('header_output', 'decoder_output', 848 'exec_output', 'decode_block'): 849 del vars[k] 850 return GenCode(**vars) 851 852# Special null format to catch an implicit-format instruction 853# definition outside of any format block. 854class NoFormat: 855 def __init__(self): 856 self.defaultInst = '' 857 858 def defineInst(self, name, args, lineno): 859 error(lineno, 860 'instruction definition "%s" with no active format!' % name) 861 862# This dictionary maps format name strings to Format objects. 863formatMap = {} 864 865# Define a new format 866def defFormat(id, params, code, lineno): 867 # make sure we haven't already defined this one 868 if formatMap.get(id, None) != None: 869 error(lineno, 'format %s redefined.' % id) 870 # create new object and store in global map 871 formatMap[id] = Format(id, params, code) 872 873 874############## 875# Stack: a simple stack object. Used for both formats (formatStack) 876# and default cases (defaultStack). Simply wraps a list to give more 877# stack-like syntax and enable initialization with an argument list 878# (as opposed to an argument that's a list). 879 880class Stack(list): 881 def __init__(self, *items): 882 list.__init__(self, items) 883 884 def push(self, item): 885 self.append(item); 886 887 def top(self): 888 return self[-1] 889 890# The global format stack. 891formatStack = Stack(NoFormat()) 892 893# The global default case stack. 894defaultStack = Stack( None ) 895 896# Global stack that tracks current file and line number. 897# Each element is a tuple (filename, lineno) that records the 898# *current* filename and the line number in the *previous* file where 899# it was included. 900fileNameStack = Stack() 901 902################### 903# Utility functions 904 905# 906# Indent every line in string 's' by two spaces 907# (except preprocessor directives). 908# Used to make nested code blocks look pretty. 909# 910def indent(s): 911 return re.sub(r'(?m)^(?!#)', ' ', s) 912 913# 914# Munge a somewhat arbitrarily formatted piece of Python code 915# (e.g. from a format 'let' block) into something whose indentation 916# will get by the Python parser. 917# 918# The two keys here are that Python will give a syntax error if 919# there's any whitespace at the beginning of the first line, and that 920# all lines at the same lexical nesting level must have identical 921# indentation. Unfortunately the way code literals work, an entire 922# let block tends to have some initial indentation. Rather than 923# trying to figure out what that is and strip it off, we prepend 'if 924# 1:' to make the let code the nested block inside the if (and have 925# the parser automatically deal with the indentation for us). 926# 927# We don't want to do this if (1) the code block is empty or (2) the 928# first line of the block doesn't have any whitespace at the front. 929 930def fixPythonIndentation(s): 931 # get rid of blank lines first 932 s = re.sub(r'(?m)^\s*\n', '', s); 933 if (s != '' and re.match(r'[ \t]', s[0])): 934 s = 'if 1:\n' + s 935 return s 936 937# Error handler. Just call exit. Output formatted to work under 938# Emacs compile-mode. Optional 'print_traceback' arg, if set to True, 939# prints a Python stack backtrace too (can be handy when trying to 940# debug the parser itself). 941def error(lineno, string, print_traceback = False): 942 spaces = "" 943 for (filename, line) in fileNameStack[0:-1]: 944 print spaces + "In file included from " + filename + ":" 945 spaces += " " 946 # Print a Python stack backtrace if requested. 947 if (print_traceback): 948 traceback.print_exc() 949 if lineno != 0: 950 line_str = "%d:" % lineno 951 else: 952 line_str = "" 953 sys.exit(spaces + "%s:%s %s" % (fileNameStack[-1][0], line_str, string)) 954 955 956##################################################################### 957# 958# Bitfield Operator Support 959# 960##################################################################### 961 962bitOp1ArgRE = re.compile(r'<\s*(\w+)\s*:\s*>') 963 964bitOpWordRE = re.compile(r'(?<![\w\.])([\w\.]+)<\s*(\w+)\s*:\s*(\w+)\s*>') 965bitOpExprRE = re.compile(r'\)<\s*(\w+)\s*:\s*(\w+)\s*>') 966 967def substBitOps(code): 968 # first convert single-bit selectors to two-index form 969 # i.e., <n> --> <n:n> 970 code = bitOp1ArgRE.sub(r'<\1:\1>', code) 971 # simple case: selector applied to ID (name) 972 # i.e., foo<a:b> --> bits(foo, a, b) 973 code = bitOpWordRE.sub(r'bits(\1, \2, \3)', code) 974 # if selector is applied to expression (ending in ')'), 975 # we need to search backward for matching '(' 976 match = bitOpExprRE.search(code) 977 while match: 978 exprEnd = match.start() 979 here = exprEnd - 1 980 nestLevel = 1 981 while nestLevel > 0: 982 if code[here] == '(': 983 nestLevel -= 1 984 elif code[here] == ')': 985 nestLevel += 1 986 here -= 1 987 if here < 0: 988 sys.exit("Didn't find '('!") 989 exprStart = here+1 990 newExpr = r'bits(%s, %s, %s)' % (code[exprStart:exprEnd+1], 991 match.group(1), match.group(2)) 992 code = code[:exprStart] + newExpr + code[match.end():] 993 match = bitOpExprRE.search(code) 994 return code 995 996 997#################### 998# Template objects. 999# 1000# Template objects are format strings that allow substitution from 1001# the attribute spaces of other objects (e.g. InstObjParams instances). 1002 1003class Template: 1004 def __init__(self, t): 1005 self.template = t 1006 1007 def subst(self, d): 1008 # Start with the template namespace. Make a copy since we're 1009 # going to modify it. 1010 myDict = templateMap.copy() 1011 # if the argument is a dictionary, we just use it. 1012 if isinstance(d, dict): 1013 myDict.update(d) 1014 # if the argument is an object, we use its attribute map. 1015 elif hasattr(d, '__dict__'): 1016 myDict.update(d.__dict__) 1017 else: 1018 raise TypeError, "Template.subst() arg must be or have dictionary" 1019 # Protect non-Python-dict substitutions (e.g. if there's a printf 1020 # in the templated C++ code) 1021 template = protect_non_subst_percents(self.template) 1022 # CPU-model-specific substitutions are handled later (in GenCode). 1023 template = protect_cpu_symbols(template) 1024 return template % myDict 1025 1026 # Convert to string. This handles the case when a template with a 1027 # CPU-specific term gets interpolated into another template or into 1028 # an output block. 1029 def __str__(self): 1030 return expand_cpu_symbols_to_string(self.template) 1031 1032##################################################################### 1033# 1034# Code Parser 1035# 1036# The remaining code is the support for automatically extracting 1037# instruction characteristics from pseudocode. 1038# 1039##################################################################### 1040 1041# Force the argument to be a list. Useful for flags, where a caller 1042# can specify a singleton flag or a list of flags. Also usful for 1043# converting tuples to lists so they can be modified. 1044def makeList(arg): 1045 if isinstance(arg, list): 1046 return arg 1047 elif isinstance(arg, tuple): 1048 return list(arg) 1049 elif not arg: 1050 return [] 1051 else: 1052 return [ arg ] 1053 1054# Generate operandTypeMap from the user's 'def operand_types' 1055# statement. 1056def buildOperandTypeMap(userDict, lineno): 1057 global operandTypeMap 1058 operandTypeMap = {} 1059 for (ext, (desc, size)) in userDict.iteritems(): 1060 if desc == 'signed int': 1061 ctype = 'int%d_t' % size 1062 is_signed = 1 1063 elif desc == 'unsigned int': 1064 ctype = 'uint%d_t' % size 1065 is_signed = 0 1066 elif desc == 'float': 1067 is_signed = 1 # shouldn't really matter 1068 if size == 32: 1069 ctype = 'float' 1070 elif size == 64: 1071 ctype = 'double' 1072 if ctype == '': 1073 error(lineno, 'Unrecognized type description "%s" in userDict') 1074 operandTypeMap[ext] = (size, ctype, is_signed) 1075 1076# 1077# 1078# 1079# Base class for operand descriptors. An instance of this class (or 1080# actually a class derived from this one) represents a specific 1081# operand for a code block (e.g, "Rc.sq" as a dest). Intermediate 1082# derived classes encapsulates the traits of a particular operand type 1083# (e.g., "32-bit integer register"). 1084# 1085class Operand(object): 1086 def __init__(self, full_name, ext, is_src, is_dest): 1087 self.full_name = full_name 1088 self.ext = ext 1089 self.is_src = is_src 1090 self.is_dest = is_dest 1091 # The 'effective extension' (eff_ext) is either the actual 1092 # extension, if one was explicitly provided, or the default. 1093 if ext: 1094 self.eff_ext = ext 1095 else: 1096 self.eff_ext = self.dflt_ext 1097 1098 (self.size, self.ctype, self.is_signed) = operandTypeMap[self.eff_ext] 1099 1100 # note that mem_acc_size is undefined for non-mem operands... 1101 # template must be careful not to use it if it doesn't apply. 1102 if self.isMem(): 1103 self.mem_acc_size = self.makeAccSize() 1104 self.mem_acc_type = self.ctype 1105 1106 # Finalize additional fields (primarily code fields). This step 1107 # is done separately since some of these fields may depend on the 1108 # register index enumeration that hasn't been performed yet at the 1109 # time of __init__(). 1110 def finalize(self): 1111 self.flags = self.getFlags() 1112 self.constructor = self.makeConstructor() 1113 self.op_decl = self.makeDecl() 1114 1115 if self.is_src: 1116 self.op_rd = self.makeRead() 1117 self.op_src_decl = self.makeDecl() 1118 else: 1119 self.op_rd = '' 1120 self.op_src_decl = '' 1121 1122 if self.is_dest: 1123 self.op_wb = self.makeWrite() 1124 self.op_dest_decl = self.makeDecl() 1125 else: 1126 self.op_wb = '' 1127 self.op_dest_decl = '' 1128 1129 def isMem(self): 1130 return 0 1131 1132 def isReg(self): 1133 return 0 1134 1135 def isFloatReg(self): 1136 return 0 1137 1138 def isIntReg(self): 1139 return 0 1140 1141 def isControlReg(self): 1142 return 0 1143 1144 def getFlags(self): 1145 # note the empty slice '[:]' gives us a copy of self.flags[0] 1146 # instead of a reference to it 1147 my_flags = self.flags[0][:] 1148 if self.is_src: 1149 my_flags += self.flags[1] 1150 if self.is_dest: 1151 my_flags += self.flags[2] 1152 return my_flags 1153 1154 def makeDecl(self): 1155 # Note that initializations in the declarations are solely 1156 # to avoid 'uninitialized variable' errors from the compiler. 1157 return self.ctype + ' ' + self.base_name + ' = 0;\n'; 1158 1159class IntRegOperand(Operand): 1160 def isReg(self): 1161 return 1 1162 1163 def isIntReg(self): 1164 return 1 1165 1166 def makeConstructor(self): 1167 c = '' 1168 if self.is_src: 1169 c += '\n\t_srcRegIdx[%d] = %s;' % \ 1170 (self.src_reg_idx, self.reg_spec) 1171 if self.is_dest: 1172 c += '\n\t_destRegIdx[%d] = %s;' % \ 1173 (self.dest_reg_idx, self.reg_spec) 1174 return c 1175 1176 def makeRead(self): 1177 if (self.ctype == 'float' or self.ctype == 'double'): 1178 error(0, 'Attempt to read integer register as FP') 1179 if (self.size == self.dflt_size): 1180 return '%s = xc->readIntReg(this, %d);\n' % \ 1181 (self.base_name, self.src_reg_idx) 1182 else: 1183 return '%s = bits(xc->readIntReg(this, %d), %d, 0);\n' % \ 1184 (self.base_name, self.src_reg_idx, self.size-1) 1185 1186 def makeWrite(self): 1187 if (self.ctype == 'float' or self.ctype == 'double'): 1188 error(0, 'Attempt to write integer register as FP') 1189 if (self.size != self.dflt_size and self.is_signed): 1190 final_val = 'sext<%d>(%s)' % (self.size, self.base_name) 1191 else: 1192 final_val = self.base_name 1193 wb = ''' 1194 { 1195 %s final_val = %s; 1196 xc->setIntReg(this, %d, final_val);\n 1197 if (traceData) { traceData->setData(final_val); } 1198 }''' % (self.dflt_ctype, final_val, self.dest_reg_idx) 1199 return wb 1200 1201class FloatRegOperand(Operand): 1202 def isReg(self): 1203 return 1 1204 1205 def isFloatReg(self): 1206 return 1 1207 1208 def makeConstructor(self): 1209 c = '' 1210 if self.is_src: 1211 c += '\n\t_srcRegIdx[%d] = %s + FP_Base_DepTag;' % \ 1212 (self.src_reg_idx, self.reg_spec) 1213 if self.is_dest: 1214 c += '\n\t_destRegIdx[%d] = %s + FP_Base_DepTag;' % \ 1215 (self.dest_reg_idx, self.reg_spec) 1216 return c 1217 1218 def makeRead(self): 1219 bit_select = 0 1220 width = 0; 1221 if (self.ctype == 'float'): 1222 func = 'readFloatReg' 1223 width = 32; 1224 elif (self.ctype == 'double'): 1225 func = 'readFloatReg' 1226 width = 64; 1227 else: 1228 func = 'readFloatRegBits' 1229 if (self.ctype == 'uint32_t'): 1230 width = 32; 1231 elif (self.ctype == 'uint64_t'): 1232 width = 64; 1233 if (self.size != self.dflt_size): 1234 bit_select = 1 1235 if width: 1236 base = 'xc->%s(this, %d, %d)' % \ 1237 (func, self.src_reg_idx, width) 1238 else: 1239 base = 'xc->%s(this, %d)' % \ 1240 (func, self.src_reg_idx) 1241 if bit_select: 1242 return '%s = bits(%s, %d, 0);\n' % \ 1243 (self.base_name, base, self.size-1) 1244 else: 1245 return '%s = %s;\n' % (self.base_name, base) 1246 1247 def makeWrite(self): 1248 final_val = self.base_name 1249 final_ctype = self.ctype 1250 widthSpecifier = '' 1251 width = 0 1252 if (self.ctype == 'float'): 1253 width = 32 1254 func = 'setFloatReg' 1255 elif (self.ctype == 'double'): 1256 width = 64 1257 func = 'setFloatReg' 1258 elif (self.ctype == 'uint32_t'): 1259 func = 'setFloatRegBits' 1260 width = 32 1261 elif (self.ctype == 'uint64_t'): 1262 func = 'setFloatRegBits' 1263 width = 64 1264 else: 1265 func = 'setFloatRegBits' 1266 final_ctype = 'uint%d_t' % self.dflt_size 1267 if (self.size != self.dflt_size and self.is_signed): 1268 final_val = 'sext<%d>(%s)' % (self.size, self.base_name) 1269 if width: 1270 widthSpecifier = ', %d' % width 1271 wb = ''' 1272 { 1273 %s final_val = %s; 1274 xc->%s(this, %d, final_val%s);\n 1275 if (traceData) { traceData->setData(final_val); } 1276 }''' % (final_ctype, final_val, func, self.dest_reg_idx, 1277 widthSpecifier) 1278 return wb 1279 1280class ControlRegOperand(Operand): 1281 def isReg(self): 1282 return 1 1283 1284 def isControlReg(self): 1285 return 1 1286 1287 def makeConstructor(self): 1288 c = '' 1289 if self.is_src: 1290 c += '\n\t_srcRegIdx[%d] = %s;' % \ 1291 (self.src_reg_idx, self.reg_spec) 1292 if self.is_dest: 1293 c += '\n\t_destRegIdx[%d] = %s;' % \ 1294 (self.dest_reg_idx, self.reg_spec) 1295 return c 1296 1297 def makeRead(self): 1298 bit_select = 0 1299 if (self.ctype == 'float' or self.ctype == 'double'): 1300 error(0, 'Attempt to read control register as FP') 1301 base = 'xc->readMiscReg(%s)' % self.reg_spec 1302 if self.size == self.dflt_size: 1303 return '%s = %s;\n' % (self.base_name, base) 1304 else: 1305 return '%s = bits(%s, %d, 0);\n' % \ 1306 (self.base_name, base, self.size-1) 1307 1308 def makeWrite(self): 1309 if (self.ctype == 'float' or self.ctype == 'double'): 1310 error(0, 'Attempt to write control register as FP') 1311 wb = 'xc->setMiscReg(%s, %s);\n' % (self.reg_spec, self.base_name) 1312 wb += 'if (traceData) { traceData->setData(%s); }' % \ 1313 self.base_name 1314 return wb 1315 1316class MemOperand(Operand): 1317 def isMem(self): 1318 return 1 1319 1320 def makeConstructor(self): 1321 return '' 1322 1323 def makeDecl(self): 1324 # Note that initializations in the declarations are solely 1325 # to avoid 'uninitialized variable' errors from the compiler. 1326 # Declare memory data variable. 1327 c = '%s %s = 0;\n' % (self.ctype, self.base_name) 1328 return c 1329 1330 def makeRead(self): 1331 return '' 1332 1333 def makeWrite(self): 1334 return '' 1335 1336 # Return the memory access size *in bits*, suitable for 1337 # forming a type via "uint%d_t". Divide by 8 if you want bytes. 1338 def makeAccSize(self): 1339 return self.size 1340 1341 1342class NPCOperand(Operand): 1343 def makeConstructor(self): 1344 return '' 1345 1346 def makeRead(self): 1347 return '%s = xc->readNextPC();\n' % self.base_name 1348 1349 def makeWrite(self): 1350 return 'xc->setNextPC(%s);\n' % self.base_name 1351 1352class NNPCOperand(Operand): 1353 def makeConstructor(self): 1354 return '' 1355 1356 def makeRead(self): 1357 return '%s = xc->readNextNPC();\n' % self.base_name 1358 1359 def makeWrite(self): 1360 return 'xc->setNextNPC(%s);\n' % self.base_name 1361 1362def buildOperandNameMap(userDict, lineno): 1363 global operandNameMap 1364 operandNameMap = {} 1365 for (op_name, val) in userDict.iteritems(): 1366 (base_cls_name, dflt_ext, reg_spec, flags, sort_pri) = val 1367 (dflt_size, dflt_ctype, dflt_is_signed) = operandTypeMap[dflt_ext] 1368 # Canonical flag structure is a triple of lists, where each list 1369 # indicates the set of flags implied by this operand always, when 1370 # used as a source, and when used as a dest, respectively. 1371 # For simplicity this can be initialized using a variety of fairly 1372 # obvious shortcuts; we convert these to canonical form here. 1373 if not flags: 1374 # no flags specified (e.g., 'None') 1375 flags = ( [], [], [] ) 1376 elif isinstance(flags, str): 1377 # a single flag: assumed to be unconditional 1378 flags = ( [ flags ], [], [] ) 1379 elif isinstance(flags, list): 1380 # a list of flags: also assumed to be unconditional 1381 flags = ( flags, [], [] ) 1382 elif isinstance(flags, tuple): 1383 # it's a tuple: it should be a triple, 1384 # but each item could be a single string or a list 1385 (uncond_flags, src_flags, dest_flags) = flags 1386 flags = (makeList(uncond_flags), 1387 makeList(src_flags), makeList(dest_flags)) 1388 # Accumulate attributes of new operand class in tmp_dict 1389 tmp_dict = {} 1390 for attr in ('dflt_ext', 'reg_spec', 'flags', 'sort_pri', 1391 'dflt_size', 'dflt_ctype', 'dflt_is_signed'): 1392 tmp_dict[attr] = eval(attr) 1393 tmp_dict['base_name'] = op_name 1394 # New class name will be e.g. "IntReg_Ra" 1395 cls_name = base_cls_name + '_' + op_name 1396 # Evaluate string arg to get class object. Note that the 1397 # actual base class for "IntReg" is "IntRegOperand", i.e. we 1398 # have to append "Operand". 1399 try: 1400 base_cls = eval(base_cls_name + 'Operand') 1401 except NameError: 1402 error(lineno, 1403 'error: unknown operand base class "%s"' % base_cls_name) 1404 # The following statement creates a new class called 1405 # <cls_name> as a subclass of <base_cls> with the attributes 1406 # in tmp_dict, just as if we evaluated a class declaration. 1407 operandNameMap[op_name] = type(cls_name, (base_cls,), tmp_dict) 1408 1409 # Define operand variables. 1410 operands = userDict.keys() 1411 1412 operandsREString = (r''' 1413 (?<![\w\.]) # neg. lookbehind assertion: prevent partial matches 1414 ((%s)(?:\.(\w+))?) # match: operand with optional '.' then suffix 1415 (?![\w\.]) # neg. lookahead assertion: prevent partial matches 1416 ''' 1417 % string.join(operands, '|')) 1418 1419 global operandsRE 1420 operandsRE = re.compile(operandsREString, re.MULTILINE|re.VERBOSE) 1421 1422 # Same as operandsREString, but extension is mandatory, and only two 1423 # groups are returned (base and ext, not full name as above). 1424 # Used for subtituting '_' for '.' to make C++ identifiers. 1425 operandsWithExtREString = (r'(?<![\w\.])(%s)\.(\w+)(?![\w\.])' 1426 % string.join(operands, '|')) 1427 1428 global operandsWithExtRE 1429 operandsWithExtRE = re.compile(operandsWithExtREString, re.MULTILINE) 1430 1431 1432class OperandList: 1433 1434 # Find all the operands in the given code block. Returns an operand 1435 # descriptor list (instance of class OperandList). 1436 def __init__(self, code): 1437 self.items = [] 1438 self.bases = {} 1439 # delete comments so we don't match on reg specifiers inside 1440 code = commentRE.sub('', code) 1441 # search for operands 1442 next_pos = 0 1443 while 1: 1444 match = operandsRE.search(code, next_pos) 1445 if not match: 1446 # no more matches: we're done 1447 break 1448 op = match.groups() 1449 # regexp groups are operand full name, base, and extension 1450 (op_full, op_base, op_ext) = op 1451 # if the token following the operand is an assignment, this is 1452 # a destination (LHS), else it's a source (RHS) 1453 is_dest = (assignRE.match(code, match.end()) != None) 1454 is_src = not is_dest 1455 # see if we've already seen this one 1456 op_desc = self.find_base(op_base) 1457 if op_desc: 1458 if op_desc.ext != op_ext: 1459 error(0, 'Inconsistent extensions for operand %s' % \ 1460 op_base) 1461 op_desc.is_src = op_desc.is_src or is_src 1462 op_desc.is_dest = op_desc.is_dest or is_dest 1463 else: 1464 # new operand: create new descriptor 1465 op_desc = operandNameMap[op_base](op_full, op_ext, 1466 is_src, is_dest) 1467 self.append(op_desc) 1468 # start next search after end of current match 1469 next_pos = match.end() 1470 self.sort() 1471 # enumerate source & dest register operands... used in building 1472 # constructor later 1473 self.numSrcRegs = 0 1474 self.numDestRegs = 0 1475 self.numFPDestRegs = 0 1476 self.numIntDestRegs = 0 1477 self.memOperand = None 1478 for op_desc in self.items: 1479 if op_desc.isReg(): 1480 if op_desc.is_src: 1481 op_desc.src_reg_idx = self.numSrcRegs 1482 self.numSrcRegs += 1 1483 if op_desc.is_dest: 1484 op_desc.dest_reg_idx = self.numDestRegs 1485 self.numDestRegs += 1 1486 if op_desc.isFloatReg(): 1487 self.numFPDestRegs += 1 1488 elif op_desc.isIntReg(): 1489 self.numIntDestRegs += 1 1490 elif op_desc.isMem(): 1491 if self.memOperand: 1492 error(0, "Code block has more than one memory operand.") 1493 self.memOperand = op_desc 1494 # now make a final pass to finalize op_desc fields that may depend 1495 # on the register enumeration 1496 for op_desc in self.items: 1497 op_desc.finalize() 1498 1499 def __len__(self): 1500 return len(self.items) 1501 1502 def __getitem__(self, index): 1503 return self.items[index] 1504 1505 def append(self, op_desc): 1506 self.items.append(op_desc) 1507 self.bases[op_desc.base_name] = op_desc 1508 1509 def find_base(self, base_name): 1510 # like self.bases[base_name], but returns None if not found 1511 # (rather than raising exception) 1512 return self.bases.get(base_name) 1513 1514 # internal helper function for concat[Some]Attr{Strings|Lists} 1515 def __internalConcatAttrs(self, attr_name, filter, result): 1516 for op_desc in self.items: 1517 if filter(op_desc): 1518 result += getattr(op_desc, attr_name) 1519 return result 1520 1521 # return a single string that is the concatenation of the (string) 1522 # values of the specified attribute for all operands 1523 def concatAttrStrings(self, attr_name): 1524 return self.__internalConcatAttrs(attr_name, lambda x: 1, '') 1525 1526 # like concatAttrStrings, but only include the values for the operands 1527 # for which the provided filter function returns true 1528 def concatSomeAttrStrings(self, filter, attr_name): 1529 return self.__internalConcatAttrs(attr_name, filter, '') 1530 1531 # return a single list that is the concatenation of the (list) 1532 # values of the specified attribute for all operands 1533 def concatAttrLists(self, attr_name): 1534 return self.__internalConcatAttrs(attr_name, lambda x: 1, []) 1535 1536 # like concatAttrLists, but only include the values for the operands 1537 # for which the provided filter function returns true 1538 def concatSomeAttrLists(self, filter, attr_name): 1539 return self.__internalConcatAttrs(attr_name, filter, []) 1540 1541 def sort(self): 1542 self.items.sort(lambda a, b: a.sort_pri - b.sort_pri) 1543 1544# Regular expression object to match C++ comments 1545# (used in findOperands()) 1546commentRE = re.compile(r'//.*\n') 1547 1548# Regular expression object to match assignment statements 1549# (used in findOperands()) 1550assignRE = re.compile(r'\s*=(?!=)', re.MULTILINE) 1551 1552# Munge operand names in code string to make legal C++ variable names. 1553# This means getting rid of the type extension if any. 1554# (Will match base_name attribute of Operand object.) 1555def substMungedOpNames(code): 1556 return operandsWithExtRE.sub(r'\1', code) 1557 1558def joinLists(t): 1559 return map(string.join, t) 1560 1561def makeFlagConstructor(flag_list): 1562 if len(flag_list) == 0: 1563 return '' 1564 # filter out repeated flags 1565 flag_list.sort() 1566 i = 1 1567 while i < len(flag_list): 1568 if flag_list[i] == flag_list[i-1]: 1569 del flag_list[i] 1570 else: 1571 i += 1 1572 pre = '\n\tflags[' 1573 post = '] = true;' 1574 code = pre + string.join(flag_list, post + pre) + post 1575 return code 1576 1577class CodeBlock: 1578 def __init__(self, code): 1579 self.orig_code = code 1580 self.operands = OperandList(code) 1581 self.code = substMungedOpNames(substBitOps(code)) 1582 self.constructor = self.operands.concatAttrStrings('constructor') 1583 self.constructor += \ 1584 '\n\t_numSrcRegs = %d;' % self.operands.numSrcRegs 1585 self.constructor += \ 1586 '\n\t_numDestRegs = %d;' % self.operands.numDestRegs 1587 self.constructor += \ 1588 '\n\t_numFPDestRegs = %d;' % self.operands.numFPDestRegs 1589 self.constructor += \ 1590 '\n\t_numIntDestRegs = %d;' % self.operands.numIntDestRegs 1591 1592 self.op_decl = self.operands.concatAttrStrings('op_decl') 1593 1594 is_src = lambda op: op.is_src 1595 is_dest = lambda op: op.is_dest 1596 1597 self.op_src_decl = \ 1598 self.operands.concatSomeAttrStrings(is_src, 'op_src_decl') 1599 self.op_dest_decl = \ 1600 self.operands.concatSomeAttrStrings(is_dest, 'op_dest_decl') 1601 1602 self.op_rd = self.operands.concatAttrStrings('op_rd') 1603 self.op_wb = self.operands.concatAttrStrings('op_wb') 1604 1605 self.flags = self.operands.concatAttrLists('flags') 1606 1607 if self.operands.memOperand: 1608 self.mem_acc_size = self.operands.memOperand.mem_acc_size 1609 self.mem_acc_type = self.operands.memOperand.mem_acc_type 1610 1611 # Make a basic guess on the operand class (function unit type). 1612 # These are good enough for most cases, and will be overridden 1613 # later otherwise. 1614 if 'IsStore' in self.flags: 1615 self.op_class = 'MemWriteOp' 1616 elif 'IsLoad' in self.flags or 'IsPrefetch' in self.flags: 1617 self.op_class = 'MemReadOp' 1618 elif 'IsFloating' in self.flags: 1619 self.op_class = 'FloatAddOp' 1620 else: 1621 self.op_class = 'IntAluOp' 1622 1623# Assume all instruction flags are of the form 'IsFoo' 1624instFlagRE = re.compile(r'Is.*') 1625 1626# OpClass constants end in 'Op' except No_OpClass 1627opClassRE = re.compile(r'.*Op|No_OpClass') 1628 1629class InstObjParams: 1630 def __init__(self, mnem, class_name, base_class = '', 1631 code = None, opt_args = [], *extras): 1632 self.mnemonic = mnem 1633 self.class_name = class_name 1634 self.base_class = base_class 1635 if code: 1636 #If the user already made a CodeBlock, pick the parts from it 1637 if isinstance(code, CodeBlock): 1638 origCode = code.orig_code 1639 codeBlock = code 1640 else: 1641 origCode = code 1642 codeBlock = CodeBlock(code) 1643 compositeCode = '\n'.join([origCode] + 1644 [pair[1] for pair in extras]) 1645 compositeBlock = CodeBlock(compositeCode) 1646 for code_attr in compositeBlock.__dict__.keys(): 1647 setattr(self, code_attr, getattr(compositeBlock, code_attr)) 1648 for (key, snippet) in extras: 1649 setattr(self, key, CodeBlock(snippet).code) 1650 self.code = codeBlock.code 1651 self.orig_code = origCode 1652 else: 1653 self.constructor = '' 1654 self.flags = [] 1655 # Optional arguments are assumed to be either StaticInst flags 1656 # or an OpClass value. To avoid having to import a complete 1657 # list of these values to match against, we do it ad-hoc 1658 # with regexps. 1659 for oa in opt_args: 1660 if instFlagRE.match(oa): 1661 self.flags.append(oa) 1662 elif opClassRE.match(oa): 1663 self.op_class = oa 1664 else: 1665 error(0, 'InstObjParams: optional arg "%s" not recognized ' 1666 'as StaticInst::Flag or OpClass.' % oa) 1667 1668 # add flag initialization to contructor here to include 1669 # any flags added via opt_args 1670 self.constructor += makeFlagConstructor(self.flags) 1671 1672 # if 'IsFloating' is set, add call to the FP enable check 1673 # function (which should be provided by isa_desc via a declare) 1674 if 'IsFloating' in self.flags: 1675 self.fp_enable_check = 'fault = checkFpEnableFault(xc);' 1676 else: 1677 self.fp_enable_check = '' 1678 1679####################### 1680# 1681# Output file template 1682# 1683 1684file_template = ''' 1685/* 1686 * DO NOT EDIT THIS FILE!!! 1687 * 1688 * It was automatically generated from the ISA description in %(filename)s 1689 */ 1690 1691%(includes)s 1692 1693%(global_output)s 1694 1695namespace %(namespace)s { 1696 1697%(namespace_output)s 1698 1699} // namespace %(namespace)s 1700 1701%(decode_function)s 1702''' 1703 1704 1705# Update the output file only if the new contents are different from 1706# the current contents. Minimizes the files that need to be rebuilt 1707# after minor changes. 1708def update_if_needed(file, contents): 1709 update = False 1710 if os.access(file, os.R_OK): 1711 f = open(file, 'r') 1712 old_contents = f.read() 1713 f.close() 1714 if contents != old_contents: 1715 print 'Updating', file 1716 os.remove(file) # in case it's write-protected 1717 update = True 1718 else: 1719 print 'File', file, 'is unchanged' 1720 else: 1721 print 'Generating', file 1722 update = True 1723 if update: 1724 f = open(file, 'w') 1725 f.write(contents) 1726 f.close() 1727 1728# This regular expression matches '##include' directives 1729includeRE = re.compile(r'^\s*##include\s+"(?P<filename>[\w/.-]*)".*$', 1730 re.MULTILINE) 1731 1732# Function to replace a matched '##include' directive with the 1733# contents of the specified file (with nested ##includes replaced 1734# recursively). 'matchobj' is an re match object (from a match of 1735# includeRE) and 'dirname' is the directory relative to which the file 1736# path should be resolved. 1737def replace_include(matchobj, dirname): 1738 fname = matchobj.group('filename') 1739 full_fname = os.path.normpath(os.path.join(dirname, fname)) 1740 contents = '##newfile "%s"\n%s\n##endfile\n' % \ 1741 (full_fname, read_and_flatten(full_fname)) 1742 return contents 1743 1744# Read a file and recursively flatten nested '##include' files. 1745def read_and_flatten(filename): 1746 current_dir = os.path.dirname(filename) 1747 try: 1748 contents = open(filename).read() 1749 except IOError: 1750 error(0, 'Error including file "%s"' % filename) 1751 fileNameStack.push((filename, 0)) 1752 # Find any includes and include them 1753 contents = includeRE.sub(lambda m: replace_include(m, current_dir), 1754 contents) 1755 fileNameStack.pop() 1756 return contents 1757 1758# 1759# Read in and parse the ISA description. 1760# 1761def parse_isa_desc(isa_desc_file, output_dir): 1762 # Read file and (recursively) all included files into a string. 1763 # PLY requires that the input be in a single string so we have to 1764 # do this up front. 1765 isa_desc = read_and_flatten(isa_desc_file) 1766 1767 # Initialize filename stack with outer file. 1768 fileNameStack.push((isa_desc_file, 0)) 1769 1770 # Parse it. 1771 (isa_name, namespace, global_code, namespace_code) = yacc.parse(isa_desc) 1772 1773 # grab the last three path components of isa_desc_file to put in 1774 # the output 1775 filename = '/'.join(isa_desc_file.split('/')[-3:]) 1776 1777 # generate decoder.hh 1778 includes = '#include "base/bitfield.hh" // for bitfield support' 1779 global_output = global_code.header_output 1780 namespace_output = namespace_code.header_output 1781 decode_function = '' 1782 update_if_needed(output_dir + '/decoder.hh', file_template % vars()) 1783 1784 # generate decoder.cc 1785 includes = '#include "decoder.hh"' 1786 global_output = global_code.decoder_output 1787 namespace_output = namespace_code.decoder_output 1788 # namespace_output += namespace_code.decode_block 1789 decode_function = namespace_code.decode_block 1790 update_if_needed(output_dir + '/decoder.cc', file_template % vars()) 1791 1792 # generate per-cpu exec files 1793 for cpu in cpu_models: 1794 includes = '#include "decoder.hh"\n' 1795 includes += cpu.includes 1796 global_output = global_code.exec_output[cpu.name] 1797 namespace_output = namespace_code.exec_output[cpu.name] 1798 decode_function = '' 1799 update_if_needed(output_dir + '/' + cpu.filename, 1800 file_template % vars()) 1801 1802# global list of CpuModel objects (see cpu_models.py) 1803cpu_models = [] 1804 1805# Called as script: get args from command line. 1806# Args are: <path to cpu_models.py> <isa desc file> <output dir> <cpu models> 1807if __name__ == '__main__': 1808 execfile(sys.argv[1]) # read in CpuModel definitions 1809 cpu_models = [CpuModel.dict[cpu] for cpu in sys.argv[4:]] 1810 parse_isa_desc(sys.argv[2], sys.argv[3]) 1811