isa_parser.py revision 2665:a124942bacb8
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# 27# Authors: Steve Reinhardt 28 29import os 30import sys 31import re 32import string 33import traceback 34# get type names 35from types import * 36 37# Prepend the directory where the PLY lex & yacc modules are found 38# to the search path. Assumes we're compiling in a subdirectory 39# of 'build' in the current tree. 40sys.path[0:0] = [os.environ['M5_PLY']] 41 42import lex 43import yacc 44 45##################################################################### 46# 47# Lexer 48# 49# The PLY lexer module takes two things as input: 50# - A list of token names (the string list 'tokens') 51# - A regular expression describing a match for each token. The 52# regexp for token FOO can be provided in two ways: 53# - as a string variable named t_FOO 54# - as the doc string for a function named t_FOO. In this case, 55# the function is also executed, allowing an action to be 56# associated with each token match. 57# 58##################################################################### 59 60# Reserved words. These are listed separately as they are matched 61# using the same regexp as generic IDs, but distinguished in the 62# t_ID() function. The PLY documentation suggests this approach. 63reserved = ( 64 'BITFIELD', 'DECODE', 'DECODER', 'DEFAULT', 'DEF', 'EXEC', 'FORMAT', 65 'HEADER', 'LET', 'NAMESPACE', 'OPERAND_TYPES', 'OPERANDS', 66 'OUTPUT', 'SIGNED', 'TEMPLATE' 67 ) 68 69# List of tokens. The lex module requires this. 70tokens = reserved + ( 71 # identifier 72 'ID', 73 74 # integer literal 75 'INTLIT', 76 77 # string literal 78 'STRLIT', 79 80 # code literal 81 'CODELIT', 82 83 # ( ) [ ] { } < > , ; : :: * 84 'LPAREN', 'RPAREN', 85 'LBRACKET', 'RBRACKET', 86 'LBRACE', 'RBRACE', 87 'LESS', 'GREATER', 'EQUALS', 88 'COMMA', 'SEMI', 'COLON', 'DBLCOLON', 89 'ASTERISK', 90 91 # C preprocessor directives 92 'CPPDIRECTIVE' 93 94# The following are matched but never returned. commented out to 95# suppress PLY warning 96 # newfile directive 97# 'NEWFILE', 98 99 # endfile directive 100# 'ENDFILE' 101) 102 103# Regular expressions for token matching 104t_LPAREN = r'\(' 105t_RPAREN = r'\)' 106t_LBRACKET = r'\[' 107t_RBRACKET = r'\]' 108t_LBRACE = r'\{' 109t_RBRACE = r'\}' 110t_LESS = r'\<' 111t_GREATER = r'\>' 112t_EQUALS = r'=' 113t_COMMA = r',' 114t_SEMI = r';' 115t_COLON = r':' 116t_DBLCOLON = r'::' 117t_ASTERISK = r'\*' 118 119# Identifiers and reserved words 120reserved_map = { } 121for r in reserved: 122 reserved_map[r.lower()] = r 123 124def t_ID(t): 125 r'[A-Za-z_]\w*' 126 t.type = reserved_map.get(t.value,'ID') 127 return t 128 129# Integer literal 130def t_INTLIT(t): 131 r'(0x[\da-fA-F]+)|\d+' 132 try: 133 t.value = int(t.value,0) 134 except ValueError: 135 error(t.lineno, 'Integer value "%s" too large' % t.value) 136 t.value = 0 137 return t 138 139# String literal. Note that these use only single quotes, and 140# can span multiple lines. 141def t_STRLIT(t): 142 r"(?m)'([^'])+'" 143 # strip off quotes 144 t.value = t.value[1:-1] 145 t.lineno += t.value.count('\n') 146 return t 147 148 149# "Code literal"... like a string literal, but delimiters are 150# '{{' and '}}' so they get formatted nicely under emacs c-mode 151def t_CODELIT(t): 152 r"(?m)\{\{([^\}]|}(?!\}))+\}\}" 153 # strip off {{ & }} 154 t.value = t.value[2:-2] 155 t.lineno += t.value.count('\n') 156 return t 157 158def t_CPPDIRECTIVE(t): 159 r'^\#[^\#].*\n' 160 t.lineno += t.value.count('\n') 161 return t 162 163def t_NEWFILE(t): 164 r'^\#\#newfile\s+"[\w/.-]*"' 165 fileNameStack.push((t.value[11:-1], t.lineno)) 166 t.lineno = 0 167 168def t_ENDFILE(t): 169 r'^\#\#endfile' 170 (old_filename, t.lineno) = fileNameStack.pop() 171 172# 173# The functions t_NEWLINE, t_ignore, and t_error are 174# special for the lex module. 175# 176 177# Newlines 178def t_NEWLINE(t): 179 r'\n+' 180 t.lineno += t.value.count('\n') 181 182# Comments 183def t_comment(t): 184 r'//.*' 185 186# Completely ignored characters 187t_ignore = ' \t\x0c' 188 189# Error handler 190def t_error(t): 191 error(t.lineno, "illegal character '%s'" % t.value[0]) 192 t.skip(1) 193 194# Build the lexer 195lex.lex() 196 197##################################################################### 198# 199# Parser 200# 201# Every function whose name starts with 'p_' defines a grammar rule. 202# The rule is encoded in the function's doc string, while the 203# function body provides the action taken when the rule is matched. 204# The argument to each function is a list of the values of the 205# rule's symbols: t[0] for the LHS, and t[1..n] for the symbols 206# on the RHS. For tokens, the value is copied from the t.value 207# attribute provided by the lexer. For non-terminals, the value 208# is assigned by the producing rule; i.e., the job of the grammar 209# rule function is to set the value for the non-terminal on the LHS 210# (by assigning to t[0]). 211##################################################################### 212 213# The LHS of the first grammar rule is used as the start symbol 214# (in this case, 'specification'). Note that this rule enforces 215# that there will be exactly one namespace declaration, with 0 or more 216# global defs/decls before and after it. The defs & decls before 217# the namespace decl will be outside the namespace; those after 218# will be inside. The decoder function is always inside the namespace. 219def p_specification(t): 220 'specification : opt_defs_and_outputs name_decl opt_defs_and_outputs decode_block' 221 global_code = t[1] 222 isa_name = t[2] 223 namespace = isa_name + "Inst" 224 # wrap the decode block as a function definition 225 t[4].wrap_decode_block(''' 226StaticInstPtr 227%(isa_name)s::decodeInst(%(isa_name)s::ExtMachInst machInst) 228{ 229 using namespace %(namespace)s; 230''' % vars(), '}') 231 # both the latter output blocks and the decode block are in the namespace 232 namespace_code = t[3] + t[4] 233 # pass it all back to the caller of yacc.parse() 234 t[0] = (isa_name, namespace, global_code, namespace_code) 235 236# ISA name declaration looks like "namespace <foo>;" 237def p_name_decl(t): 238 'name_decl : NAMESPACE ID SEMI' 239 t[0] = t[2] 240 241# 'opt_defs_and_outputs' is a possibly empty sequence of 242# def and/or output statements. 243def p_opt_defs_and_outputs_0(t): 244 'opt_defs_and_outputs : empty' 245 t[0] = GenCode() 246 247def p_opt_defs_and_outputs_1(t): 248 'opt_defs_and_outputs : defs_and_outputs' 249 t[0] = t[1] 250 251def p_defs_and_outputs_0(t): 252 'defs_and_outputs : def_or_output' 253 t[0] = t[1] 254 255def p_defs_and_outputs_1(t): 256 'defs_and_outputs : defs_and_outputs def_or_output' 257 t[0] = t[1] + t[2] 258 259# The list of possible definition/output statements. 260def p_def_or_output(t): 261 '''def_or_output : def_format 262 | def_bitfield 263 | def_template 264 | def_operand_types 265 | def_operands 266 | output_header 267 | output_decoder 268 | output_exec 269 | global_let''' 270 t[0] = t[1] 271 272# Output blocks 'output <foo> {{...}}' (C++ code blocks) are copied 273# directly to the appropriate output section. 274 275 276# Protect any non-dict-substitution '%'s in a format string 277# (i.e. those not followed by '(') 278def protect_non_subst_percents(s): 279 return re.sub(r'%(?!\()', '%%', s) 280 281# Massage output block by substituting in template definitions and bit 282# operators. We handle '%'s embedded in the string that don't 283# indicate template substitutions (or CPU-specific symbols, which get 284# handled in GenCode) by doubling them first so that the format 285# operation will reduce them back to single '%'s. 286def process_output(s): 287 s = protect_non_subst_percents(s) 288 # protects cpu-specific symbols too 289 s = protect_cpu_symbols(s) 290 return substBitOps(s % templateMap) 291 292def p_output_header(t): 293 'output_header : OUTPUT HEADER CODELIT SEMI' 294 t[0] = GenCode(header_output = process_output(t[3])) 295 296def p_output_decoder(t): 297 'output_decoder : OUTPUT DECODER CODELIT SEMI' 298 t[0] = GenCode(decoder_output = process_output(t[3])) 299 300def p_output_exec(t): 301 'output_exec : OUTPUT EXEC CODELIT SEMI' 302 t[0] = GenCode(exec_output = process_output(t[3])) 303 304# global let blocks 'let {{...}}' (Python code blocks) are executed 305# directly when seen. Note that these execute in a special variable 306# context 'exportContext' to prevent the code from polluting this 307# script's namespace. 308def p_global_let(t): 309 'global_let : LET CODELIT SEMI' 310 updateExportContext() 311 try: 312 exec fixPythonIndentation(t[2]) in exportContext 313 except Exception, exc: 314 error(t.lineno(1), 315 'error: %s in global let block "%s".' % (exc, t[2])) 316 t[0] = GenCode() # contributes nothing to the output C++ file 317 318# Define the mapping from operand type extensions to C++ types and bit 319# widths (stored in operandTypeMap). 320def p_def_operand_types(t): 321 'def_operand_types : DEF OPERAND_TYPES CODELIT SEMI' 322 try: 323 userDict = eval('{' + t[3] + '}') 324 except Exception, exc: 325 error(t.lineno(1), 326 'error: %s in def operand_types block "%s".' % (exc, t[3])) 327 buildOperandTypeMap(userDict, t.lineno(1)) 328 t[0] = GenCode() # contributes nothing to the output C++ file 329 330# Define the mapping from operand names to operand classes and other 331# traits. Stored in operandNameMap. 332def p_def_operands(t): 333 'def_operands : DEF OPERANDS CODELIT SEMI' 334 if not globals().has_key('operandTypeMap'): 335 error(t.lineno(1), 336 'error: operand types must be defined before operands') 337 try: 338 userDict = eval('{' + t[3] + '}') 339 except Exception, exc: 340 error(t.lineno(1), 341 'error: %s in def operands block "%s".' % (exc, t[3])) 342 buildOperandNameMap(userDict, t.lineno(1)) 343 t[0] = GenCode() # contributes nothing to the output C++ file 344 345# A bitfield definition looks like: 346# 'def [signed] bitfield <ID> [<first>:<last>]' 347# This generates a preprocessor macro in the output file. 348def p_def_bitfield_0(t): 349 'def_bitfield : DEF opt_signed BITFIELD ID LESS INTLIT COLON INTLIT GREATER SEMI' 350 expr = 'bits(machInst, %2d, %2d)' % (t[6], t[8]) 351 if (t[2] == 'signed'): 352 expr = 'sext<%d>(%s)' % (t[6] - t[8] + 1, expr) 353 hash_define = '#undef %s\n#define %s\t%s\n' % (t[4], t[4], expr) 354 t[0] = GenCode(header_output = hash_define) 355 356# alternate form for single bit: 'def [signed] bitfield <ID> [<bit>]' 357def p_def_bitfield_1(t): 358 'def_bitfield : DEF opt_signed BITFIELD ID LESS INTLIT GREATER SEMI' 359 expr = 'bits(machInst, %2d, %2d)' % (t[6], t[6]) 360 if (t[2] == 'signed'): 361 expr = 'sext<%d>(%s)' % (1, expr) 362 hash_define = '#undef %s\n#define %s\t%s\n' % (t[4], t[4], expr) 363 t[0] = GenCode(header_output = hash_define) 364 365def p_opt_signed_0(t): 366 'opt_signed : SIGNED' 367 t[0] = t[1] 368 369def p_opt_signed_1(t): 370 'opt_signed : empty' 371 t[0] = '' 372 373# Global map variable to hold templates 374templateMap = {} 375 376def p_def_template(t): 377 'def_template : DEF TEMPLATE ID CODELIT SEMI' 378 templateMap[t[3]] = Template(t[4]) 379 t[0] = GenCode() 380 381# An instruction format definition looks like 382# "def format <fmt>(<params>) {{...}};" 383def p_def_format(t): 384 'def_format : DEF FORMAT ID LPAREN param_list RPAREN CODELIT SEMI' 385 (id, params, code) = (t[3], t[5], t[7]) 386 defFormat(id, params, code, t.lineno(1)) 387 t[0] = GenCode() 388 389# The formal parameter list for an instruction format is a possibly 390# empty list of comma-separated parameters. Positional (standard, 391# non-keyword) parameters must come first, followed by keyword 392# parameters, followed by a '*foo' parameter that gets excess 393# positional arguments (as in Python). Each of these three parameter 394# categories is optional. 395# 396# Note that we do not support the '**foo' parameter for collecting 397# otherwise undefined keyword args. Otherwise the parameter list is 398# (I believe) identical to what is supported in Python. 399# 400# The param list generates a tuple, where the first element is a list of 401# the positional params and the second element is a dict containing the 402# keyword params. 403def p_param_list_0(t): 404 'param_list : positional_param_list COMMA nonpositional_param_list' 405 t[0] = t[1] + t[3] 406 407def p_param_list_1(t): 408 '''param_list : positional_param_list 409 | nonpositional_param_list''' 410 t[0] = t[1] 411 412def p_positional_param_list_0(t): 413 'positional_param_list : empty' 414 t[0] = [] 415 416def p_positional_param_list_1(t): 417 'positional_param_list : ID' 418 t[0] = [t[1]] 419 420def p_positional_param_list_2(t): 421 'positional_param_list : positional_param_list COMMA ID' 422 t[0] = t[1] + [t[3]] 423 424def p_nonpositional_param_list_0(t): 425 'nonpositional_param_list : keyword_param_list COMMA excess_args_param' 426 t[0] = t[1] + t[3] 427 428def p_nonpositional_param_list_1(t): 429 '''nonpositional_param_list : keyword_param_list 430 | excess_args_param''' 431 t[0] = t[1] 432 433def p_keyword_param_list_0(t): 434 'keyword_param_list : keyword_param' 435 t[0] = [t[1]] 436 437def p_keyword_param_list_1(t): 438 'keyword_param_list : keyword_param_list COMMA keyword_param' 439 t[0] = t[1] + [t[3]] 440 441def p_keyword_param(t): 442 'keyword_param : ID EQUALS expr' 443 t[0] = t[1] + ' = ' + t[3].__repr__() 444 445def p_excess_args_param(t): 446 'excess_args_param : ASTERISK ID' 447 # Just concatenate them: '*ID'. Wrap in list to be consistent 448 # with positional_param_list and keyword_param_list. 449 t[0] = [t[1] + t[2]] 450 451# End of format definition-related rules. 452############## 453 454# 455# A decode block looks like: 456# decode <field1> [, <field2>]* [default <inst>] { ... } 457# 458def p_decode_block(t): 459 'decode_block : DECODE ID opt_default LBRACE decode_stmt_list RBRACE' 460 default_defaults = defaultStack.pop() 461 codeObj = t[5] 462 # use the "default defaults" only if there was no explicit 463 # default statement in decode_stmt_list 464 if not codeObj.has_decode_default: 465 codeObj += default_defaults 466 codeObj.wrap_decode_block('switch (%s) {\n' % t[2], '}\n') 467 t[0] = codeObj 468 469# The opt_default statement serves only to push the "default defaults" 470# onto defaultStack. This value will be used by nested decode blocks, 471# and used and popped off when the current decode_block is processed 472# (in p_decode_block() above). 473def p_opt_default_0(t): 474 'opt_default : empty' 475 # no default specified: reuse the one currently at the top of the stack 476 defaultStack.push(defaultStack.top()) 477 # no meaningful value returned 478 t[0] = None 479 480def p_opt_default_1(t): 481 'opt_default : DEFAULT inst' 482 # push the new default 483 codeObj = t[2] 484 codeObj.wrap_decode_block('\ndefault:\n', 'break;\n') 485 defaultStack.push(codeObj) 486 # no meaningful value returned 487 t[0] = None 488 489def p_decode_stmt_list_0(t): 490 'decode_stmt_list : decode_stmt' 491 t[0] = t[1] 492 493def p_decode_stmt_list_1(t): 494 'decode_stmt_list : decode_stmt decode_stmt_list' 495 if (t[1].has_decode_default and t[2].has_decode_default): 496 error(t.lineno(1), 'Two default cases in decode block') 497 t[0] = t[1] + t[2] 498 499# 500# Decode statement rules 501# 502# There are four types of statements allowed in a decode block: 503# 1. Format blocks 'format <foo> { ... }' 504# 2. Nested decode blocks 505# 3. Instruction definitions. 506# 4. C preprocessor directives. 507 508 509# Preprocessor directives found in a decode statement list are passed 510# through to the output, replicated to all of the output code 511# streams. This works well for ifdefs, so we can ifdef out both the 512# declarations and the decode cases generated by an instruction 513# definition. Handling them as part of the grammar makes it easy to 514# keep them in the right place with respect to the code generated by 515# the other statements. 516def p_decode_stmt_cpp(t): 517 'decode_stmt : CPPDIRECTIVE' 518 t[0] = GenCode(t[1], t[1], t[1], t[1]) 519 520# A format block 'format <foo> { ... }' sets the default instruction 521# format used to handle instruction definitions inside the block. 522# This format can be overridden by using an explicit format on the 523# instruction definition or with a nested format block. 524def p_decode_stmt_format(t): 525 'decode_stmt : FORMAT push_format_id LBRACE decode_stmt_list RBRACE' 526 # The format will be pushed on the stack when 'push_format_id' is 527 # processed (see below). Once the parser has recognized the full 528 # production (though the right brace), we're done with the format, 529 # so now we can pop it. 530 formatStack.pop() 531 t[0] = t[4] 532 533# This rule exists so we can set the current format (& push the stack) 534# when we recognize the format name part of the format block. 535def p_push_format_id(t): 536 'push_format_id : ID' 537 try: 538 formatStack.push(formatMap[t[1]]) 539 t[0] = ('', '// format %s' % t[1]) 540 except KeyError: 541 error(t.lineno(1), 'instruction format "%s" not defined.' % t[1]) 542 543# Nested decode block: if the value of the current field matches the 544# specified constant, do a nested decode on some other field. 545def p_decode_stmt_decode(t): 546 'decode_stmt : case_label COLON decode_block' 547 label = t[1] 548 codeObj = t[3] 549 # just wrap the decoding code from the block as a case in the 550 # outer switch statement. 551 codeObj.wrap_decode_block('\n%s:\n' % label) 552 codeObj.has_decode_default = (label == 'default') 553 t[0] = codeObj 554 555# Instruction definition (finally!). 556def p_decode_stmt_inst(t): 557 'decode_stmt : case_label COLON inst SEMI' 558 label = t[1] 559 codeObj = t[3] 560 codeObj.wrap_decode_block('\n%s:' % label, 'break;\n') 561 codeObj.has_decode_default = (label == 'default') 562 t[0] = codeObj 563 564# The case label is either a list of one or more constants or 'default' 565def p_case_label_0(t): 566 'case_label : intlit_list' 567 t[0] = ': '.join(map(lambda a: 'case %#x' % a, t[1])) 568 569def p_case_label_1(t): 570 'case_label : DEFAULT' 571 t[0] = 'default' 572 573# 574# The constant list for a decode case label must be non-empty, but may have 575# one or more comma-separated integer literals in it. 576# 577def p_intlit_list_0(t): 578 'intlit_list : INTLIT' 579 t[0] = [t[1]] 580 581def p_intlit_list_1(t): 582 'intlit_list : intlit_list COMMA INTLIT' 583 t[0] = t[1] 584 t[0].append(t[3]) 585 586# Define an instruction using the current instruction format (specified 587# by an enclosing format block). 588# "<mnemonic>(<args>)" 589def p_inst_0(t): 590 'inst : ID LPAREN arg_list RPAREN' 591 # Pass the ID and arg list to the current format class to deal with. 592 currentFormat = formatStack.top() 593 codeObj = currentFormat.defineInst(t[1], t[3], t.lineno(1)) 594 args = ','.join(map(str, t[3])) 595 args = re.sub('(?m)^', '//', args) 596 args = re.sub('^//', '', args) 597 comment = '\n// %s::%s(%s)\n' % (currentFormat.id, t[1], args) 598 codeObj.prepend_all(comment) 599 t[0] = codeObj 600 601# Define an instruction using an explicitly specified format: 602# "<fmt>::<mnemonic>(<args>)" 603def p_inst_1(t): 604 'inst : ID DBLCOLON ID LPAREN arg_list RPAREN' 605 try: 606 format = formatMap[t[1]] 607 except KeyError: 608 error(t.lineno(1), 'instruction format "%s" not defined.' % t[1]) 609 codeObj = format.defineInst(t[3], t[5], t.lineno(1)) 610 comment = '\n// %s::%s(%s)\n' % (t[1], t[3], t[5]) 611 codeObj.prepend_all(comment) 612 t[0] = codeObj 613 614# The arg list generates a tuple, where the first element is a list of 615# the positional args and the second element is a dict containing the 616# keyword args. 617def p_arg_list_0(t): 618 'arg_list : positional_arg_list COMMA keyword_arg_list' 619 t[0] = ( t[1], t[3] ) 620 621def p_arg_list_1(t): 622 'arg_list : positional_arg_list' 623 t[0] = ( t[1], {} ) 624 625def p_arg_list_2(t): 626 'arg_list : keyword_arg_list' 627 t[0] = ( [], t[1] ) 628 629def p_positional_arg_list_0(t): 630 'positional_arg_list : empty' 631 t[0] = [] 632 633def p_positional_arg_list_1(t): 634 'positional_arg_list : expr' 635 t[0] = [t[1]] 636 637def p_positional_arg_list_2(t): 638 'positional_arg_list : positional_arg_list COMMA expr' 639 t[0] = t[1] + [t[3]] 640 641def p_keyword_arg_list_0(t): 642 'keyword_arg_list : keyword_arg' 643 t[0] = t[1] 644 645def p_keyword_arg_list_1(t): 646 'keyword_arg_list : keyword_arg_list COMMA keyword_arg' 647 t[0] = t[1] 648 t[0].update(t[3]) 649 650def p_keyword_arg(t): 651 'keyword_arg : ID EQUALS expr' 652 t[0] = { t[1] : t[3] } 653 654# 655# Basic expressions. These constitute the argument values of 656# "function calls" (i.e. instruction definitions in the decode block) 657# and default values for formal parameters of format functions. 658# 659# Right now, these are either strings, integers, or (recursively) 660# lists of exprs (using Python square-bracket list syntax). Note that 661# bare identifiers are trated as string constants here (since there 662# isn't really a variable namespace to refer to). 663# 664def p_expr_0(t): 665 '''expr : ID 666 | INTLIT 667 | STRLIT 668 | CODELIT''' 669 t[0] = t[1] 670 671def p_expr_1(t): 672 '''expr : LBRACKET list_expr RBRACKET''' 673 t[0] = t[2] 674 675def p_list_expr_0(t): 676 'list_expr : expr' 677 t[0] = [t[1]] 678 679def p_list_expr_1(t): 680 'list_expr : list_expr COMMA expr' 681 t[0] = t[1] + [t[3]] 682 683def p_list_expr_2(t): 684 'list_expr : empty' 685 t[0] = [] 686 687# 688# Empty production... use in other rules for readability. 689# 690def p_empty(t): 691 'empty :' 692 pass 693 694# Parse error handler. Note that the argument here is the offending 695# *token*, not a grammar symbol (hence the need to use t.value) 696def p_error(t): 697 if t: 698 error(t.lineno, "syntax error at '%s'" % t.value) 699 else: 700 error(0, "unknown syntax error", True) 701 702# END OF GRAMMAR RULES 703# 704# Now build the parser. 705yacc.yacc() 706 707 708##################################################################### 709# 710# Support Classes 711# 712##################################################################### 713 714# Expand template with CPU-specific references into a dictionary with 715# an entry for each CPU model name. The entry key is the model name 716# and the corresponding value is the template with the CPU-specific 717# refs substituted for that model. 718def expand_cpu_symbols_to_dict(template): 719 # Protect '%'s that don't go with CPU-specific terms 720 t = re.sub(r'%(?!\(CPU_)', '%%', template) 721 result = {} 722 for cpu in cpu_models: 723 result[cpu.name] = t % cpu.strings 724 return result 725 726# *If* the template has CPU-specific references, return a single 727# string containing a copy of the template for each CPU model with the 728# corresponding values substituted in. If the template has no 729# CPU-specific references, it is returned unmodified. 730def expand_cpu_symbols_to_string(template): 731 if template.find('%(CPU_') != -1: 732 return reduce(lambda x,y: x+y, 733 expand_cpu_symbols_to_dict(template).values()) 734 else: 735 return template 736 737# Protect CPU-specific references by doubling the corresponding '%'s 738# (in preparation for substituting a different set of references into 739# the template). 740def protect_cpu_symbols(template): 741 return re.sub(r'%(?=\(CPU_)', '%%', template) 742 743############### 744# GenCode class 745# 746# The GenCode class encapsulates generated code destined for various 747# output files. The header_output and decoder_output attributes are 748# strings containing code destined for decoder.hh and decoder.cc 749# respectively. The decode_block attribute contains code to be 750# incorporated in the decode function itself (that will also end up in 751# decoder.cc). The exec_output attribute is a dictionary with a key 752# for each CPU model name; the value associated with a particular key 753# is the string of code for that CPU model's exec.cc file. The 754# has_decode_default attribute is used in the decode block to allow 755# explicit default clauses to override default default clauses. 756 757class GenCode: 758 # Constructor. At this point we substitute out all CPU-specific 759 # symbols. For the exec output, these go into the per-model 760 # dictionary. For all other output types they get collapsed into 761 # a single string. 762 def __init__(self, 763 header_output = '', decoder_output = '', exec_output = '', 764 decode_block = '', has_decode_default = False): 765 self.header_output = expand_cpu_symbols_to_string(header_output) 766 self.decoder_output = expand_cpu_symbols_to_string(decoder_output) 767 if isinstance(exec_output, dict): 768 self.exec_output = exec_output 769 elif isinstance(exec_output, str): 770 # If the exec_output arg is a single string, we replicate 771 # it for each of the CPU models, substituting and 772 # %(CPU_foo)s params appropriately. 773 self.exec_output = expand_cpu_symbols_to_dict(exec_output) 774 self.decode_block = expand_cpu_symbols_to_string(decode_block) 775 self.has_decode_default = has_decode_default 776 777 # Override '+' operator: generate a new GenCode object that 778 # concatenates all the individual strings in the operands. 779 def __add__(self, other): 780 exec_output = {} 781 for cpu in cpu_models: 782 n = cpu.name 783 exec_output[n] = self.exec_output[n] + other.exec_output[n] 784 return GenCode(self.header_output + other.header_output, 785 self.decoder_output + other.decoder_output, 786 exec_output, 787 self.decode_block + other.decode_block, 788 self.has_decode_default or other.has_decode_default) 789 790 # Prepend a string (typically a comment) to all the strings. 791 def prepend_all(self, pre): 792 self.header_output = pre + self.header_output 793 self.decoder_output = pre + self.decoder_output 794 self.decode_block = pre + self.decode_block 795 for cpu in cpu_models: 796 self.exec_output[cpu.name] = pre + self.exec_output[cpu.name] 797 798 # Wrap the decode block in a pair of strings (e.g., 'case foo:' 799 # and 'break;'). Used to build the big nested switch statement. 800 def wrap_decode_block(self, pre, post = ''): 801 self.decode_block = pre + indent(self.decode_block) + post 802 803################ 804# Format object. 805# 806# A format object encapsulates an instruction format. It must provide 807# a defineInst() method that generates the code for an instruction 808# definition. 809 810exportContextSymbols = ('InstObjParams', 'CodeBlock', 811 'makeList', 're', 'string') 812 813exportContext = {} 814 815def updateExportContext(): 816 exportContext.update(exportDict(*exportContextSymbols)) 817 exportContext.update(templateMap) 818 819def exportDict(*symNames): 820 return dict([(s, eval(s)) for s in symNames]) 821 822 823class Format: 824 def __init__(self, id, params, code): 825 # constructor: just save away arguments 826 self.id = id 827 self.params = params 828 label = 'def format ' + id 829 self.user_code = compile(fixPythonIndentation(code), label, 'exec') 830 param_list = string.join(params, ", ") 831 f = '''def defInst(_code, _context, %s): 832 my_locals = vars().copy() 833 exec _code in _context, my_locals 834 return my_locals\n''' % param_list 835 c = compile(f, label + ' wrapper', 'exec') 836 exec c 837 self.func = defInst 838 839 def defineInst(self, name, args, lineno): 840 context = {} 841 updateExportContext() 842 context.update(exportContext) 843 context.update({ 'name': name, 'Name': string.capitalize(name) }) 844 try: 845 vars = self.func(self.user_code, context, *args[0], **args[1]) 846 except Exception, exc: 847 error(lineno, 'error defining "%s": %s.' % (name, exc)) 848 for k in vars.keys(): 849 if k not in ('header_output', 'decoder_output', 850 'exec_output', 'decode_block'): 851 del vars[k] 852 return GenCode(**vars) 853 854# Special null format to catch an implicit-format instruction 855# definition outside of any format block. 856class NoFormat: 857 def __init__(self): 858 self.defaultInst = '' 859 860 def defineInst(self, name, args, lineno): 861 error(lineno, 862 'instruction definition "%s" with no active format!' % name) 863 864# This dictionary maps format name strings to Format objects. 865formatMap = {} 866 867# Define a new format 868def defFormat(id, params, code, lineno): 869 # make sure we haven't already defined this one 870 if formatMap.get(id, None) != None: 871 error(lineno, 'format %s redefined.' % id) 872 # create new object and store in global map 873 formatMap[id] = Format(id, params, code) 874 875 876############## 877# Stack: a simple stack object. Used for both formats (formatStack) 878# and default cases (defaultStack). Simply wraps a list to give more 879# stack-like syntax and enable initialization with an argument list 880# (as opposed to an argument that's a list). 881 882class Stack(list): 883 def __init__(self, *items): 884 list.__init__(self, items) 885 886 def push(self, item): 887 self.append(item); 888 889 def top(self): 890 return self[-1] 891 892# The global format stack. 893formatStack = Stack(NoFormat()) 894 895# The global default case stack. 896defaultStack = Stack( None ) 897 898# Global stack that tracks current file and line number. 899# Each element is a tuple (filename, lineno) that records the 900# *current* filename and the line number in the *previous* file where 901# it was included. 902fileNameStack = Stack() 903 904################### 905# Utility functions 906 907# 908# Indent every line in string 's' by two spaces 909# (except preprocessor directives). 910# Used to make nested code blocks look pretty. 911# 912def indent(s): 913 return re.sub(r'(?m)^(?!#)', ' ', s) 914 915# 916# Munge a somewhat arbitrarily formatted piece of Python code 917# (e.g. from a format 'let' block) into something whose indentation 918# will get by the Python parser. 919# 920# The two keys here are that Python will give a syntax error if 921# there's any whitespace at the beginning of the first line, and that 922# all lines at the same lexical nesting level must have identical 923# indentation. Unfortunately the way code literals work, an entire 924# let block tends to have some initial indentation. Rather than 925# trying to figure out what that is and strip it off, we prepend 'if 926# 1:' to make the let code the nested block inside the if (and have 927# the parser automatically deal with the indentation for us). 928# 929# We don't want to do this if (1) the code block is empty or (2) the 930# first line of the block doesn't have any whitespace at the front. 931 932def fixPythonIndentation(s): 933 # get rid of blank lines first 934 s = re.sub(r'(?m)^\s*\n', '', s); 935 if (s != '' and re.match(r'[ \t]', s[0])): 936 s = 'if 1:\n' + s 937 return s 938 939# Error handler. Just call exit. Output formatted to work under 940# Emacs compile-mode. Optional 'print_traceback' arg, if set to True, 941# prints a Python stack backtrace too (can be handy when trying to 942# debug the parser itself). 943def error(lineno, string, print_traceback = False): 944 spaces = "" 945 for (filename, line) in fileNameStack[0:-1]: 946 print spaces + "In file included from " + filename + ":" 947 spaces += " " 948 # Print a Python stack backtrace if requested. 949 if (print_traceback): 950 traceback.print_exc() 951 if lineno != 0: 952 line_str = "%d:" % lineno 953 else: 954 line_str = "" 955 sys.exit(spaces + "%s:%s %s" % (fileNameStack[-1][0], line_str, string)) 956 957 958##################################################################### 959# 960# Bitfield Operator Support 961# 962##################################################################### 963 964bitOp1ArgRE = re.compile(r'<\s*(\w+)\s*:\s*>') 965 966bitOpWordRE = re.compile(r'(?<![\w\.])([\w\.]+)<\s*(\w+)\s*:\s*(\w+)\s*>') 967bitOpExprRE = re.compile(r'\)<\s*(\w+)\s*:\s*(\w+)\s*>') 968 969def substBitOps(code): 970 # first convert single-bit selectors to two-index form 971 # i.e., <n> --> <n:n> 972 code = bitOp1ArgRE.sub(r'<\1:\1>', code) 973 # simple case: selector applied to ID (name) 974 # i.e., foo<a:b> --> bits(foo, a, b) 975 code = bitOpWordRE.sub(r'bits(\1, \2, \3)', code) 976 # if selector is applied to expression (ending in ')'), 977 # we need to search backward for matching '(' 978 match = bitOpExprRE.search(code) 979 while match: 980 exprEnd = match.start() 981 here = exprEnd - 1 982 nestLevel = 1 983 while nestLevel > 0: 984 if code[here] == '(': 985 nestLevel -= 1 986 elif code[here] == ')': 987 nestLevel += 1 988 here -= 1 989 if here < 0: 990 sys.exit("Didn't find '('!") 991 exprStart = here+1 992 newExpr = r'bits(%s, %s, %s)' % (code[exprStart:exprEnd+1], 993 match.group(1), match.group(2)) 994 code = code[:exprStart] + newExpr + code[match.end():] 995 match = bitOpExprRE.search(code) 996 return code 997 998 999#################### 1000# Template objects. 1001# 1002# Template objects are format strings that allow substitution from 1003# the attribute spaces of other objects (e.g. InstObjParams instances). 1004 1005class Template: 1006 def __init__(self, t): 1007 self.template = t 1008 1009 def subst(self, d): 1010 # Start with the template namespace. Make a copy since we're 1011 # going to modify it. 1012 myDict = templateMap.copy() 1013 # if the argument is a dictionary, we just use it. 1014 if isinstance(d, dict): 1015 myDict.update(d) 1016 # if the argument is an object, we use its attribute map. 1017 elif hasattr(d, '__dict__'): 1018 myDict.update(d.__dict__) 1019 else: 1020 raise TypeError, "Template.subst() arg must be or have dictionary" 1021 # Protect non-Python-dict substitutions (e.g. if there's a printf 1022 # in the templated C++ code) 1023 template = protect_non_subst_percents(self.template) 1024 # CPU-model-specific substitutions are handled later (in GenCode). 1025 template = protect_cpu_symbols(template) 1026 return template % myDict 1027 1028 # Convert to string. This handles the case when a template with a 1029 # CPU-specific term gets interpolated into another template or into 1030 # an output block. 1031 def __str__(self): 1032 return expand_cpu_symbols_to_string(self.template) 1033 1034##################################################################### 1035# 1036# Code Parser 1037# 1038# The remaining code is the support for automatically extracting 1039# instruction characteristics from pseudocode. 1040# 1041##################################################################### 1042 1043# Force the argument to be a list. Useful for flags, where a caller 1044# can specify a singleton flag or a list of flags. Also usful for 1045# converting tuples to lists so they can be modified. 1046def makeList(arg): 1047 if isinstance(arg, list): 1048 return arg 1049 elif isinstance(arg, tuple): 1050 return list(arg) 1051 elif not arg: 1052 return [] 1053 else: 1054 return [ arg ] 1055 1056# Generate operandTypeMap from the user's 'def operand_types' 1057# statement. 1058def buildOperandTypeMap(userDict, lineno): 1059 global operandTypeMap 1060 operandTypeMap = {} 1061 for (ext, (desc, size)) in userDict.iteritems(): 1062 if desc == 'signed int': 1063 ctype = 'int%d_t' % size 1064 is_signed = 1 1065 elif desc == 'unsigned int': 1066 ctype = 'uint%d_t' % size 1067 is_signed = 0 1068 elif desc == 'float': 1069 is_signed = 1 # shouldn't really matter 1070 if size == 32: 1071 ctype = 'float' 1072 elif size == 64: 1073 ctype = 'double' 1074 if ctype == '': 1075 error(lineno, 'Unrecognized type description "%s" in userDict') 1076 operandTypeMap[ext] = (size, ctype, is_signed) 1077 1078# 1079# 1080# 1081# Base class for operand descriptors. An instance of this class (or 1082# actually a class derived from this one) represents a specific 1083# operand for a code block (e.g, "Rc.sq" as a dest). Intermediate 1084# derived classes encapsulates the traits of a particular operand type 1085# (e.g., "32-bit integer register"). 1086# 1087class Operand(object): 1088 def __init__(self, full_name, ext, is_src, is_dest): 1089 self.full_name = full_name 1090 self.ext = ext 1091 self.is_src = is_src 1092 self.is_dest = is_dest 1093 # The 'effective extension' (eff_ext) is either the actual 1094 # extension, if one was explicitly provided, or the default. 1095 if ext: 1096 self.eff_ext = ext 1097 else: 1098 self.eff_ext = self.dflt_ext 1099 1100 (self.size, self.ctype, self.is_signed) = operandTypeMap[self.eff_ext] 1101 1102 # note that mem_acc_size is undefined for non-mem operands... 1103 # template must be careful not to use it if it doesn't apply. 1104 if self.isMem(): 1105 self.mem_acc_size = self.makeAccSize() 1106 self.mem_acc_type = self.ctype 1107 1108 # Finalize additional fields (primarily code fields). This step 1109 # is done separately since some of these fields may depend on the 1110 # register index enumeration that hasn't been performed yet at the 1111 # time of __init__(). 1112 def finalize(self): 1113 self.flags = self.getFlags() 1114 self.constructor = self.makeConstructor() 1115 self.op_decl = self.makeDecl() 1116 1117 if self.is_src: 1118 self.op_rd = self.makeRead() 1119 self.op_src_decl = self.makeDecl() 1120 else: 1121 self.op_rd = '' 1122 self.op_src_decl = '' 1123 1124 if self.is_dest: 1125 self.op_wb = self.makeWrite() 1126 self.op_dest_decl = self.makeDecl() 1127 else: 1128 self.op_wb = '' 1129 self.op_dest_decl = '' 1130 1131 def isMem(self): 1132 return 0 1133 1134 def isReg(self): 1135 return 0 1136 1137 def isFloatReg(self): 1138 return 0 1139 1140 def isIntReg(self): 1141 return 0 1142 1143 def isControlReg(self): 1144 return 0 1145 1146 def getFlags(self): 1147 # note the empty slice '[:]' gives us a copy of self.flags[0] 1148 # instead of a reference to it 1149 my_flags = self.flags[0][:] 1150 if self.is_src: 1151 my_flags += self.flags[1] 1152 if self.is_dest: 1153 my_flags += self.flags[2] 1154 return my_flags 1155 1156 def makeDecl(self): 1157 # Note that initializations in the declarations are solely 1158 # to avoid 'uninitialized variable' errors from the compiler. 1159 return self.ctype + ' ' + self.base_name + ' = 0;\n'; 1160 1161class IntRegOperand(Operand): 1162 def isReg(self): 1163 return 1 1164 1165 def isIntReg(self): 1166 return 1 1167 1168 def makeConstructor(self): 1169 c = '' 1170 if self.is_src: 1171 c += '\n\t_srcRegIdx[%d] = %s;' % \ 1172 (self.src_reg_idx, self.reg_spec) 1173 if self.is_dest: 1174 c += '\n\t_destRegIdx[%d] = %s;' % \ 1175 (self.dest_reg_idx, self.reg_spec) 1176 return c 1177 1178 def makeRead(self): 1179 if (self.ctype == 'float' or self.ctype == 'double'): 1180 error(0, 'Attempt to read integer register as FP') 1181 if (self.size == self.dflt_size): 1182 return '%s = xc->readIntReg(this, %d);\n' % \ 1183 (self.base_name, self.src_reg_idx) 1184 else: 1185 return '%s = bits(xc->readIntReg(this, %d), %d, 0);\n' % \ 1186 (self.base_name, self.src_reg_idx, self.size-1) 1187 1188 def makeWrite(self): 1189 if (self.ctype == 'float' or self.ctype == 'double'): 1190 error(0, 'Attempt to write integer register as FP') 1191 if (self.size != self.dflt_size and self.is_signed): 1192 final_val = 'sext<%d>(%s)' % (self.size, self.base_name) 1193 else: 1194 final_val = self.base_name 1195 wb = ''' 1196 { 1197 %s final_val = %s; 1198 xc->setIntReg(this, %d, final_val);\n 1199 if (traceData) { traceData->setData(final_val); } 1200 }''' % (self.dflt_ctype, final_val, self.dest_reg_idx) 1201 return wb 1202 1203class FloatRegOperand(Operand): 1204 def isReg(self): 1205 return 1 1206 1207 def isFloatReg(self): 1208 return 1 1209 1210 def makeConstructor(self): 1211 c = '' 1212 if self.is_src: 1213 c += '\n\t_srcRegIdx[%d] = %s + FP_Base_DepTag;' % \ 1214 (self.src_reg_idx, self.reg_spec) 1215 if self.is_dest: 1216 c += '\n\t_destRegIdx[%d] = %s + FP_Base_DepTag;' % \ 1217 (self.dest_reg_idx, self.reg_spec) 1218 return c 1219 1220 def makeRead(self): 1221 bit_select = 0 1222 width = 0; 1223 if (self.ctype == 'float'): 1224 func = 'readFloatReg' 1225 width = 32; 1226 elif (self.ctype == 'double'): 1227 func = 'readFloatReg' 1228 width = 64; 1229 else: 1230 func = 'readFloatRegBits' 1231 if (self.ctype == 'uint32_t'): 1232 width = 32; 1233 elif (self.ctype == 'uint64_t'): 1234 width = 64; 1235 if (self.size != self.dflt_size): 1236 bit_select = 1 1237 if width: 1238 base = 'xc->%s(this, %d, %d)' % \ 1239 (func, self.src_reg_idx, width) 1240 else: 1241 base = 'xc->%s(this, %d)' % \ 1242 (func, self.src_reg_idx) 1243 if bit_select: 1244 return '%s = bits(%s, %d, 0);\n' % \ 1245 (self.base_name, base, self.size-1) 1246 else: 1247 return '%s = %s;\n' % (self.base_name, base) 1248 1249 def makeWrite(self): 1250 final_val = self.base_name 1251 final_ctype = self.ctype 1252 widthSpecifier = '' 1253 width = 0 1254 if (self.ctype == 'float'): 1255 width = 32 1256 func = 'setFloatReg' 1257 elif (self.ctype == 'double'): 1258 width = 64 1259 func = 'setFloatReg' 1260 elif (self.ctype == 'uint32_t'): 1261 func = 'setFloatRegBits' 1262 width = 32 1263 elif (self.ctype == 'uint64_t'): 1264 func = 'setFloatRegBits' 1265 width = 64 1266 else: 1267 func = 'setFloatRegBits' 1268 final_ctype = 'uint%d_t' % self.dflt_size 1269 if (self.size != self.dflt_size and self.is_signed): 1270 final_val = 'sext<%d>(%s)' % (self.size, self.base_name) 1271 if width: 1272 widthSpecifier = ', %d' % width 1273 wb = ''' 1274 { 1275 %s final_val = %s; 1276 xc->%s(this, %d, final_val%s);\n 1277 if (traceData) { traceData->setData(final_val); } 1278 }''' % (final_ctype, final_val, func, self.dest_reg_idx, 1279 widthSpecifier) 1280 return wb 1281 1282class ControlRegOperand(Operand): 1283 def isReg(self): 1284 return 1 1285 1286 def isControlReg(self): 1287 return 1 1288 1289 def makeConstructor(self): 1290 c = '' 1291 if self.is_src: 1292 c += '\n\t_srcRegIdx[%d] = %s;' % \ 1293 (self.src_reg_idx, self.reg_spec) 1294 if self.is_dest: 1295 c += '\n\t_destRegIdx[%d] = %s;' % \ 1296 (self.dest_reg_idx, self.reg_spec) 1297 return c 1298 1299 def makeRead(self): 1300 bit_select = 0 1301 if (self.ctype == 'float' or self.ctype == 'double'): 1302 error(0, 'Attempt to read control register as FP') 1303 base = 'xc->readMiscReg(%s)' % self.reg_spec 1304 if self.size == self.dflt_size: 1305 return '%s = %s;\n' % (self.base_name, base) 1306 else: 1307 return '%s = bits(%s, %d, 0);\n' % \ 1308 (self.base_name, base, self.size-1) 1309 1310 def makeWrite(self): 1311 if (self.ctype == 'float' or self.ctype == 'double'): 1312 error(0, 'Attempt to write control register as FP') 1313 wb = 'xc->setMiscReg(%s, %s);\n' % (self.reg_spec, self.base_name) 1314 wb += 'if (traceData) { traceData->setData(%s); }' % \ 1315 self.base_name 1316 return wb 1317 1318class MemOperand(Operand): 1319 def isMem(self): 1320 return 1 1321 1322 def makeConstructor(self): 1323 return '' 1324 1325 def makeDecl(self): 1326 # Note that initializations in the declarations are solely 1327 # to avoid 'uninitialized variable' errors from the compiler. 1328 # Declare memory data variable. 1329 c = '%s %s = 0;\n' % (self.ctype, self.base_name) 1330 return c 1331 1332 def makeRead(self): 1333 return '' 1334 1335 def makeWrite(self): 1336 return '' 1337 1338 # Return the memory access size *in bits*, suitable for 1339 # forming a type via "uint%d_t". Divide by 8 if you want bytes. 1340 def makeAccSize(self): 1341 return self.size 1342 1343 1344class NPCOperand(Operand): 1345 def makeConstructor(self): 1346 return '' 1347 1348 def makeRead(self): 1349 return '%s = xc->readNextPC();\n' % self.base_name 1350 1351 def makeWrite(self): 1352 return 'xc->setNextPC(%s);\n' % self.base_name 1353 1354class NNPCOperand(Operand): 1355 def makeConstructor(self): 1356 return '' 1357 1358 def makeRead(self): 1359 return '%s = xc->readNextNPC();\n' % self.base_name 1360 1361 def makeWrite(self): 1362 return 'xc->setNextNPC(%s);\n' % self.base_name 1363 1364def buildOperandNameMap(userDict, lineno): 1365 global operandNameMap 1366 operandNameMap = {} 1367 for (op_name, val) in userDict.iteritems(): 1368 (base_cls_name, dflt_ext, reg_spec, flags, sort_pri) = val 1369 (dflt_size, dflt_ctype, dflt_is_signed) = operandTypeMap[dflt_ext] 1370 # Canonical flag structure is a triple of lists, where each list 1371 # indicates the set of flags implied by this operand always, when 1372 # used as a source, and when used as a dest, respectively. 1373 # For simplicity this can be initialized using a variety of fairly 1374 # obvious shortcuts; we convert these to canonical form here. 1375 if not flags: 1376 # no flags specified (e.g., 'None') 1377 flags = ( [], [], [] ) 1378 elif isinstance(flags, str): 1379 # a single flag: assumed to be unconditional 1380 flags = ( [ flags ], [], [] ) 1381 elif isinstance(flags, list): 1382 # a list of flags: also assumed to be unconditional 1383 flags = ( flags, [], [] ) 1384 elif isinstance(flags, tuple): 1385 # it's a tuple: it should be a triple, 1386 # but each item could be a single string or a list 1387 (uncond_flags, src_flags, dest_flags) = flags 1388 flags = (makeList(uncond_flags), 1389 makeList(src_flags), makeList(dest_flags)) 1390 # Accumulate attributes of new operand class in tmp_dict 1391 tmp_dict = {} 1392 for attr in ('dflt_ext', 'reg_spec', 'flags', 'sort_pri', 1393 'dflt_size', 'dflt_ctype', 'dflt_is_signed'): 1394 tmp_dict[attr] = eval(attr) 1395 tmp_dict['base_name'] = op_name 1396 # New class name will be e.g. "IntReg_Ra" 1397 cls_name = base_cls_name + '_' + op_name 1398 # Evaluate string arg to get class object. Note that the 1399 # actual base class for "IntReg" is "IntRegOperand", i.e. we 1400 # have to append "Operand". 1401 try: 1402 base_cls = eval(base_cls_name + 'Operand') 1403 except NameError: 1404 error(lineno, 1405 'error: unknown operand base class "%s"' % base_cls_name) 1406 # The following statement creates a new class called 1407 # <cls_name> as a subclass of <base_cls> with the attributes 1408 # in tmp_dict, just as if we evaluated a class declaration. 1409 operandNameMap[op_name] = type(cls_name, (base_cls,), tmp_dict) 1410 1411 # Define operand variables. 1412 operands = userDict.keys() 1413 1414 operandsREString = (r''' 1415 (?<![\w\.]) # neg. lookbehind assertion: prevent partial matches 1416 ((%s)(?:\.(\w+))?) # match: operand with optional '.' then suffix 1417 (?![\w\.]) # neg. lookahead assertion: prevent partial matches 1418 ''' 1419 % string.join(operands, '|')) 1420 1421 global operandsRE 1422 operandsRE = re.compile(operandsREString, re.MULTILINE|re.VERBOSE) 1423 1424 # Same as operandsREString, but extension is mandatory, and only two 1425 # groups are returned (base and ext, not full name as above). 1426 # Used for subtituting '_' for '.' to make C++ identifiers. 1427 operandsWithExtREString = (r'(?<![\w\.])(%s)\.(\w+)(?![\w\.])' 1428 % string.join(operands, '|')) 1429 1430 global operandsWithExtRE 1431 operandsWithExtRE = re.compile(operandsWithExtREString, re.MULTILINE) 1432 1433 1434class OperandList: 1435 1436 # Find all the operands in the given code block. Returns an operand 1437 # descriptor list (instance of class OperandList). 1438 def __init__(self, code): 1439 self.items = [] 1440 self.bases = {} 1441 # delete comments so we don't match on reg specifiers inside 1442 code = commentRE.sub('', code) 1443 # search for operands 1444 next_pos = 0 1445 while 1: 1446 match = operandsRE.search(code, next_pos) 1447 if not match: 1448 # no more matches: we're done 1449 break 1450 op = match.groups() 1451 # regexp groups are operand full name, base, and extension 1452 (op_full, op_base, op_ext) = op 1453 # if the token following the operand is an assignment, this is 1454 # a destination (LHS), else it's a source (RHS) 1455 is_dest = (assignRE.match(code, match.end()) != None) 1456 is_src = not is_dest 1457 # see if we've already seen this one 1458 op_desc = self.find_base(op_base) 1459 if op_desc: 1460 if op_desc.ext != op_ext: 1461 error(0, 'Inconsistent extensions for operand %s' % \ 1462 op_base) 1463 op_desc.is_src = op_desc.is_src or is_src 1464 op_desc.is_dest = op_desc.is_dest or is_dest 1465 else: 1466 # new operand: create new descriptor 1467 op_desc = operandNameMap[op_base](op_full, op_ext, 1468 is_src, is_dest) 1469 self.append(op_desc) 1470 # start next search after end of current match 1471 next_pos = match.end() 1472 self.sort() 1473 # enumerate source & dest register operands... used in building 1474 # constructor later 1475 self.numSrcRegs = 0 1476 self.numDestRegs = 0 1477 self.numFPDestRegs = 0 1478 self.numIntDestRegs = 0 1479 self.memOperand = None 1480 for op_desc in self.items: 1481 if op_desc.isReg(): 1482 if op_desc.is_src: 1483 op_desc.src_reg_idx = self.numSrcRegs 1484 self.numSrcRegs += 1 1485 if op_desc.is_dest: 1486 op_desc.dest_reg_idx = self.numDestRegs 1487 self.numDestRegs += 1 1488 if op_desc.isFloatReg(): 1489 self.numFPDestRegs += 1 1490 elif op_desc.isIntReg(): 1491 self.numIntDestRegs += 1 1492 elif op_desc.isMem(): 1493 if self.memOperand: 1494 error(0, "Code block has more than one memory operand.") 1495 self.memOperand = op_desc 1496 # now make a final pass to finalize op_desc fields that may depend 1497 # on the register enumeration 1498 for op_desc in self.items: 1499 op_desc.finalize() 1500 1501 def __len__(self): 1502 return len(self.items) 1503 1504 def __getitem__(self, index): 1505 return self.items[index] 1506 1507 def append(self, op_desc): 1508 self.items.append(op_desc) 1509 self.bases[op_desc.base_name] = op_desc 1510 1511 def find_base(self, base_name): 1512 # like self.bases[base_name], but returns None if not found 1513 # (rather than raising exception) 1514 return self.bases.get(base_name) 1515 1516 # internal helper function for concat[Some]Attr{Strings|Lists} 1517 def __internalConcatAttrs(self, attr_name, filter, result): 1518 for op_desc in self.items: 1519 if filter(op_desc): 1520 result += getattr(op_desc, attr_name) 1521 return result 1522 1523 # return a single string that is the concatenation of the (string) 1524 # values of the specified attribute for all operands 1525 def concatAttrStrings(self, attr_name): 1526 return self.__internalConcatAttrs(attr_name, lambda x: 1, '') 1527 1528 # like concatAttrStrings, but only include the values for the operands 1529 # for which the provided filter function returns true 1530 def concatSomeAttrStrings(self, filter, attr_name): 1531 return self.__internalConcatAttrs(attr_name, filter, '') 1532 1533 # return a single list that is the concatenation of the (list) 1534 # values of the specified attribute for all operands 1535 def concatAttrLists(self, attr_name): 1536 return self.__internalConcatAttrs(attr_name, lambda x: 1, []) 1537 1538 # like concatAttrLists, but only include the values for the operands 1539 # for which the provided filter function returns true 1540 def concatSomeAttrLists(self, filter, attr_name): 1541 return self.__internalConcatAttrs(attr_name, filter, []) 1542 1543 def sort(self): 1544 self.items.sort(lambda a, b: a.sort_pri - b.sort_pri) 1545 1546# Regular expression object to match C++ comments 1547# (used in findOperands()) 1548commentRE = re.compile(r'//.*\n') 1549 1550# Regular expression object to match assignment statements 1551# (used in findOperands()) 1552assignRE = re.compile(r'\s*=(?!=)', re.MULTILINE) 1553 1554# Munge operand names in code string to make legal C++ variable names. 1555# This means getting rid of the type extension if any. 1556# (Will match base_name attribute of Operand object.) 1557def substMungedOpNames(code): 1558 return operandsWithExtRE.sub(r'\1', code) 1559 1560def joinLists(t): 1561 return map(string.join, t) 1562 1563def makeFlagConstructor(flag_list): 1564 if len(flag_list) == 0: 1565 return '' 1566 # filter out repeated flags 1567 flag_list.sort() 1568 i = 1 1569 while i < len(flag_list): 1570 if flag_list[i] == flag_list[i-1]: 1571 del flag_list[i] 1572 else: 1573 i += 1 1574 pre = '\n\tflags[' 1575 post = '] = true;' 1576 code = pre + string.join(flag_list, post + pre) + post 1577 return code 1578 1579class CodeBlock: 1580 def __init__(self, code): 1581 self.orig_code = code 1582 self.operands = OperandList(code) 1583 self.code = substMungedOpNames(substBitOps(code)) 1584 self.constructor = self.operands.concatAttrStrings('constructor') 1585 self.constructor += \ 1586 '\n\t_numSrcRegs = %d;' % self.operands.numSrcRegs 1587 self.constructor += \ 1588 '\n\t_numDestRegs = %d;' % self.operands.numDestRegs 1589 self.constructor += \ 1590 '\n\t_numFPDestRegs = %d;' % self.operands.numFPDestRegs 1591 self.constructor += \ 1592 '\n\t_numIntDestRegs = %d;' % self.operands.numIntDestRegs 1593 1594 self.op_decl = self.operands.concatAttrStrings('op_decl') 1595 1596 is_src = lambda op: op.is_src 1597 is_dest = lambda op: op.is_dest 1598 1599 self.op_src_decl = \ 1600 self.operands.concatSomeAttrStrings(is_src, 'op_src_decl') 1601 self.op_dest_decl = \ 1602 self.operands.concatSomeAttrStrings(is_dest, 'op_dest_decl') 1603 1604 self.op_rd = self.operands.concatAttrStrings('op_rd') 1605 self.op_wb = self.operands.concatAttrStrings('op_wb') 1606 1607 self.flags = self.operands.concatAttrLists('flags') 1608 1609 if self.operands.memOperand: 1610 self.mem_acc_size = self.operands.memOperand.mem_acc_size 1611 self.mem_acc_type = self.operands.memOperand.mem_acc_type 1612 1613 # Make a basic guess on the operand class (function unit type). 1614 # These are good enough for most cases, and will be overridden 1615 # later otherwise. 1616 if 'IsStore' in self.flags: 1617 self.op_class = 'MemWriteOp' 1618 elif 'IsLoad' in self.flags or 'IsPrefetch' in self.flags: 1619 self.op_class = 'MemReadOp' 1620 elif 'IsFloating' in self.flags: 1621 self.op_class = 'FloatAddOp' 1622 else: 1623 self.op_class = 'IntAluOp' 1624 1625# Assume all instruction flags are of the form 'IsFoo' 1626instFlagRE = re.compile(r'Is.*') 1627 1628# OpClass constants end in 'Op' except No_OpClass 1629opClassRE = re.compile(r'.*Op|No_OpClass') 1630 1631class InstObjParams: 1632 def __init__(self, mnem, class_name, base_class = '', 1633 code = None, opt_args = [], *extras): 1634 self.mnemonic = mnem 1635 self.class_name = class_name 1636 self.base_class = base_class 1637 if code: 1638 #If the user already made a CodeBlock, pick the parts from it 1639 if isinstance(code, CodeBlock): 1640 origCode = code.orig_code 1641 codeBlock = code 1642 else: 1643 origCode = code 1644 codeBlock = CodeBlock(code) 1645 compositeCode = '\n'.join([origCode] + 1646 [pair[1] for pair in extras]) 1647 compositeBlock = CodeBlock(compositeCode) 1648 for code_attr in compositeBlock.__dict__.keys(): 1649 setattr(self, code_attr, getattr(compositeBlock, code_attr)) 1650 for (key, snippet) in extras: 1651 setattr(self, key, CodeBlock(snippet).code) 1652 self.code = codeBlock.code 1653 self.orig_code = origCode 1654 else: 1655 self.constructor = '' 1656 self.flags = [] 1657 # Optional arguments are assumed to be either StaticInst flags 1658 # or an OpClass value. To avoid having to import a complete 1659 # list of these values to match against, we do it ad-hoc 1660 # with regexps. 1661 for oa in opt_args: 1662 if instFlagRE.match(oa): 1663 self.flags.append(oa) 1664 elif opClassRE.match(oa): 1665 self.op_class = oa 1666 else: 1667 error(0, 'InstObjParams: optional arg "%s" not recognized ' 1668 'as StaticInst::Flag or OpClass.' % oa) 1669 1670 # add flag initialization to contructor here to include 1671 # any flags added via opt_args 1672 self.constructor += makeFlagConstructor(self.flags) 1673 1674 # if 'IsFloating' is set, add call to the FP enable check 1675 # function (which should be provided by isa_desc via a declare) 1676 if 'IsFloating' in self.flags: 1677 self.fp_enable_check = 'fault = checkFpEnableFault(xc);' 1678 else: 1679 self.fp_enable_check = '' 1680 1681####################### 1682# 1683# Output file template 1684# 1685 1686file_template = ''' 1687/* 1688 * DO NOT EDIT THIS FILE!!! 1689 * 1690 * It was automatically generated from the ISA description in %(filename)s 1691 */ 1692 1693%(includes)s 1694 1695%(global_output)s 1696 1697namespace %(namespace)s { 1698 1699%(namespace_output)s 1700 1701} // namespace %(namespace)s 1702 1703%(decode_function)s 1704''' 1705 1706 1707# Update the output file only if the new contents are different from 1708# the current contents. Minimizes the files that need to be rebuilt 1709# after minor changes. 1710def update_if_needed(file, contents): 1711 update = False 1712 if os.access(file, os.R_OK): 1713 f = open(file, 'r') 1714 old_contents = f.read() 1715 f.close() 1716 if contents != old_contents: 1717 print 'Updating', file 1718 os.remove(file) # in case it's write-protected 1719 update = True 1720 else: 1721 print 'File', file, 'is unchanged' 1722 else: 1723 print 'Generating', file 1724 update = True 1725 if update: 1726 f = open(file, 'w') 1727 f.write(contents) 1728 f.close() 1729 1730# This regular expression matches '##include' directives 1731includeRE = re.compile(r'^\s*##include\s+"(?P<filename>[\w/.-]*)".*$', 1732 re.MULTILINE) 1733 1734# Function to replace a matched '##include' directive with the 1735# contents of the specified file (with nested ##includes replaced 1736# recursively). 'matchobj' is an re match object (from a match of 1737# includeRE) and 'dirname' is the directory relative to which the file 1738# path should be resolved. 1739def replace_include(matchobj, dirname): 1740 fname = matchobj.group('filename') 1741 full_fname = os.path.normpath(os.path.join(dirname, fname)) 1742 contents = '##newfile "%s"\n%s\n##endfile\n' % \ 1743 (full_fname, read_and_flatten(full_fname)) 1744 return contents 1745 1746# Read a file and recursively flatten nested '##include' files. 1747def read_and_flatten(filename): 1748 current_dir = os.path.dirname(filename) 1749 try: 1750 contents = open(filename).read() 1751 except IOError: 1752 error(0, 'Error including file "%s"' % filename) 1753 fileNameStack.push((filename, 0)) 1754 # Find any includes and include them 1755 contents = includeRE.sub(lambda m: replace_include(m, current_dir), 1756 contents) 1757 fileNameStack.pop() 1758 return contents 1759 1760# 1761# Read in and parse the ISA description. 1762# 1763def parse_isa_desc(isa_desc_file, output_dir): 1764 # Read file and (recursively) all included files into a string. 1765 # PLY requires that the input be in a single string so we have to 1766 # do this up front. 1767 isa_desc = read_and_flatten(isa_desc_file) 1768 1769 # Initialize filename stack with outer file. 1770 fileNameStack.push((isa_desc_file, 0)) 1771 1772 # Parse it. 1773 (isa_name, namespace, global_code, namespace_code) = yacc.parse(isa_desc) 1774 1775 # grab the last three path components of isa_desc_file to put in 1776 # the output 1777 filename = '/'.join(isa_desc_file.split('/')[-3:]) 1778 1779 # generate decoder.hh 1780 includes = '#include "base/bitfield.hh" // for bitfield support' 1781 global_output = global_code.header_output 1782 namespace_output = namespace_code.header_output 1783 decode_function = '' 1784 update_if_needed(output_dir + '/decoder.hh', file_template % vars()) 1785 1786 # generate decoder.cc 1787 includes = '#include "decoder.hh"' 1788 global_output = global_code.decoder_output 1789 namespace_output = namespace_code.decoder_output 1790 # namespace_output += namespace_code.decode_block 1791 decode_function = namespace_code.decode_block 1792 update_if_needed(output_dir + '/decoder.cc', file_template % vars()) 1793 1794 # generate per-cpu exec files 1795 for cpu in cpu_models: 1796 includes = '#include "decoder.hh"\n' 1797 includes += cpu.includes 1798 global_output = global_code.exec_output[cpu.name] 1799 namespace_output = namespace_code.exec_output[cpu.name] 1800 decode_function = '' 1801 update_if_needed(output_dir + '/' + cpu.filename, 1802 file_template % vars()) 1803 1804# global list of CpuModel objects (see cpu_models.py) 1805cpu_models = [] 1806 1807# Called as script: get args from command line. 1808# Args are: <path to cpu_models.py> <isa desc file> <output dir> <cpu models> 1809if __name__ == '__main__': 1810 execfile(sys.argv[1]) # read in CpuModel definitions 1811 cpu_models = [CpuModel.dict[cpu] for cpu in sys.argv[4:]] 1812 parse_isa_desc(sys.argv[2], sys.argv[3]) 1813