1 /*
2 * Copyright (c) 1997, 2010, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
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23 */
24
25 // DFA.CPP - Method definitions for outputting the matcher DFA from ADLC
26 #include "adlc.hpp"
27
28 //---------------------------Switches for debugging output---------------------
29 static bool debug_output = false;
30 static bool debug_output1 = false; // top level chain rules
31
32 //---------------------------Access to internals of class State----------------
33 static const char *sLeft = "_kids[0]";
34 static const char *sRight = "_kids[1]";
35
36 //---------------------------DFA productions-----------------------------------
37 static const char *dfa_production = "DFA_PRODUCTION";
38 static const char *dfa_production_set_valid = "DFA_PRODUCTION__SET_VALID";
39
40 //---------------------------Production State----------------------------------
41 static const char *knownInvalid = "knownInvalid"; // The result does NOT have a rule defined
42 static const char *knownValid = "knownValid"; // The result must be produced by a rule
43 static const char *unknownValid = "unknownValid"; // Unknown (probably due to a child or predicate constraint)
44
45 static const char *noConstraint = "noConstraint"; // No constraints seen so far
46 static const char *hasConstraint = "hasConstraint"; // Within the first constraint
47
48
49 //------------------------------Production------------------------------------
50 // Track the status of productions for a particular result
51 class Production {
52 public:
53 const char *_result;
54 const char *_constraint;
55 const char *_valid;
56 Expr *_cost_lb; // Cost lower bound for this production
57 Expr *_cost_ub; // Cost upper bound for this production
58
59 public:
60 Production(const char *result, const char *constraint, const char *valid);
61 ~Production() {};
62
63 void initialize(); // reset to be an empty container
64
65 const char *valid() const { return _valid; }
66 Expr *cost_lb() const { return (Expr *)_cost_lb; }
67 Expr *cost_ub() const { return (Expr *)_cost_ub; }
68
69 void print();
70 };
71
72
73 //------------------------------ProductionState--------------------------------
74 // Track the status of all production rule results
75 // Reset for each root opcode (e.g., Op_RegI, Op_AddI, ...)
76 class ProductionState {
77 private:
78 Dict _production; // map result of production, char*, to information or NULL
79 const char *_constraint;
80
81 public:
82 // cmpstr does string comparisions. hashstr computes a key.
83 ProductionState(Arena *arena) : _production(cmpstr, hashstr, arena) { initialize(); };
84 ~ProductionState() { };
85
86 void initialize(); // reset local and dictionary state
87
88 const char *constraint();
89 void set_constraint(const char *constraint); // currently working inside of constraints
90
91 const char *valid(const char *result); // unknownValid, or status for this production
92 void set_valid(const char *result); // if not constrained, set status to knownValid
93
94 Expr *cost_lb(const char *result);
95 Expr *cost_ub(const char *result);
96 void set_cost_bounds(const char *result, const Expr *cost, bool has_state_check, bool has_cost_check);
97
98 // Return the Production associated with the result,
99 // or create a new Production and insert it into the dictionary.
100 Production *getProduction(const char *result);
101
102 void print();
103
104 private:
105 // Disable public use of constructor, copy-ctor, ...
106 ProductionState( ) : _production(cmpstr, hashstr, Form::arena) { assert( false, "NotImplemented"); };
107 ProductionState( const ProductionState & ) : _production(cmpstr, hashstr, Form::arena) { assert( false, "NotImplemented"); }; // Deep-copy
108 };
109
110
111 //---------------------------Helper Functions----------------------------------
112 // cost_check template:
113 // 1) if (STATE__NOT_YET_VALID(EBXREGI) || _cost[EBXREGI] > c) {
114 // 2) DFA_PRODUCTION__SET_VALID(EBXREGI, cmovI_memu_rule, c)
115 // 3) }
116 //
117 static void cost_check(FILE *fp, const char *spaces,
118 const char *arrayIdx, const Expr *cost, const char *rule, ProductionState &status) {
119 bool state_check = false; // true if this production needs to check validity
120 bool cost_check = false; // true if this production needs to check cost
121 bool cost_is_above_upper_bound = false; // true if this production is unnecessary due to high cost
122 bool cost_is_below_lower_bound = false; // true if this production replaces a higher cost production
123
124 // Get information about this production
125 const Expr *previous_ub = status.cost_ub(arrayIdx);
126 if( !previous_ub->is_unknown() ) {
127 if( previous_ub->less_than_or_equal(cost) ) {
128 cost_is_above_upper_bound = true;
129 if( debug_output ) { fprintf(fp, "// Previous rule with lower cost than: %s === %s_rule costs %s\n", arrayIdx, rule, cost->as_string()); }
130 }
131 }
132
133 const Expr *previous_lb = status.cost_lb(arrayIdx);
134 if( !previous_lb->is_unknown() ) {
135 if( cost->less_than_or_equal(previous_lb) ) {
136 cost_is_below_lower_bound = true;
137 if( debug_output ) { fprintf(fp, "// Previous rule with higher cost\n"); }
138 }
139 }
140
141 // line 1)
142 // Check for validity and compare to other match costs
143 const char *validity_check = status.valid(arrayIdx);
144 if( validity_check == unknownValid ) {
145 fprintf(fp, "%sif (STATE__NOT_YET_VALID(%s) || _cost[%s] > %s) {\n", spaces, arrayIdx, arrayIdx, cost->as_string());
146 state_check = true;
147 cost_check = true;
148 }
149 else if( validity_check == knownInvalid ) {
150 if( debug_output ) { fprintf(fp, "%s// %s KNOWN_INVALID \n", spaces, arrayIdx); }
151 }
152 else if( validity_check == knownValid ) {
153 if( cost_is_above_upper_bound ) {
154 // production cost is known to be too high.
155 return;
156 } else if( cost_is_below_lower_bound ) {
157 // production will unconditionally overwrite a previous production that had higher cost
158 } else {
159 fprintf(fp, "%sif ( /* %s KNOWN_VALID || */ _cost[%s] > %s) {\n", spaces, arrayIdx, arrayIdx, cost->as_string());
160 cost_check = true;
161 }
162 }
163
164 // line 2)
165 // no need to set State vector if our state is knownValid
166 const char *production = (validity_check == knownValid) ? dfa_production : dfa_production_set_valid;
167 fprintf(fp, "%s %s(%s, %s_rule, %s)", spaces, production, arrayIdx, rule, cost->as_string() );
168 if( validity_check == knownValid ) {
169 if( cost_is_below_lower_bound ) { fprintf(fp, "\t // overwrites higher cost rule"); }
170 }
171 fprintf(fp, "\n");
172
173 // line 3)
174 if( cost_check || state_check ) {
175 fprintf(fp, "%s}\n", spaces);
176 }
177
178 status.set_cost_bounds(arrayIdx, cost, state_check, cost_check);
179
180 // Update ProductionState
181 if( validity_check != knownValid ) {
182 // set State vector if not previously known
183 status.set_valid(arrayIdx);
184 }
185 }
186
187
188 //---------------------------child_test----------------------------------------
189 // Example:
190 // STATE__VALID_CHILD(_kids[0], FOO) && STATE__VALID_CHILD(_kids[1], BAR)
191 // Macro equivalent to: _kids[0]->valid(FOO) && _kids[1]->valid(BAR)
192 //
193 static void child_test(FILE *fp, MatchList &mList) {
194 if( mList._lchild ) // If left child, check it
195 fprintf(fp, "STATE__VALID_CHILD(_kids[0], %s)", ArchDesc::getMachOperEnum(mList._lchild));
196 if( mList._lchild && mList._rchild ) // If both, add the "&&"
197 fprintf(fp, " && " );
198 if( mList._rchild ) // If right child, check it
199 fprintf(fp, "STATE__VALID_CHILD(_kids[1], %s)", ArchDesc::getMachOperEnum(mList._rchild));
200 }
201
202 //---------------------------calc_cost-----------------------------------------
203 // Example:
204 // unsigned int c = _kids[0]->_cost[FOO] + _kids[1]->_cost[BAR] + 5;
205 //
206 Expr *ArchDesc::calc_cost(FILE *fp, const char *spaces, MatchList &mList, ProductionState &status) {
207 fprintf(fp, "%sunsigned int c = ", spaces);
208 Expr *c = new Expr("0");
209 if (mList._lchild ) { // If left child, add it in
210 sprintf(Expr::buffer(), "_kids[0]->_cost[%s]", ArchDesc::getMachOperEnum(mList._lchild));
211 c->add(Expr::buffer());
212 }
213 if (mList._rchild) { // If right child, add it in
214 sprintf(Expr::buffer(), "_kids[1]->_cost[%s]", ArchDesc::getMachOperEnum(mList._rchild));
215 c->add(Expr::buffer());
216 }
217 // Add in cost of this rule
218 const char *mList_cost = mList.get_cost();
219 c->add(mList_cost, *this);
220
221 fprintf(fp, "%s;\n", c->as_string());
222 c->set_external_name("c");
223 return c;
224 }
225
226
227 //---------------------------gen_match-----------------------------------------
228 void ArchDesc::gen_match(FILE *fp, MatchList &mList, ProductionState &status, Dict &operands_chained_from) {
229 const char *spaces4 = " ";
230 const char *spaces6 = " ";
231
232 fprintf(fp, "%s", spaces4);
233 // Only generate child tests if this is not a leaf node
234 bool has_child_constraints = mList._lchild || mList._rchild;
235 const char *predicate_test = mList.get_pred();
236 if( has_child_constraints || predicate_test ) {
237 // Open the child-and-predicate-test braces
238 fprintf(fp, "if( ");
239 status.set_constraint(hasConstraint);
240 child_test(fp, mList);
241 // Only generate predicate test if one exists for this match
242 if( predicate_test ) {
243 if( has_child_constraints ) { fprintf(fp," &&\n"); }
244 fprintf(fp, "%s %s", spaces6, predicate_test);
245 }
246 // End of outer tests
247 fprintf(fp," ) ");
248 } else {
249 // No child or predicate test needed
250 status.set_constraint(noConstraint);
251 }
252
253 // End of outer tests
254 fprintf(fp,"{\n");
255
256 // Calculate cost of this match
257 const Expr *cost = calc_cost(fp, spaces6, mList, status);
258 // Check against other match costs, and update cost & rule vectors
259 cost_check(fp, spaces6, ArchDesc::getMachOperEnum(mList._resultStr), cost, mList._opcode, status);
260
261 // If this is a member of an operand class, update the class cost & rule
262 expand_opclass( fp, spaces6, cost, mList._resultStr, status);
263
264 // Check if this rule should be used to generate the chains as well.
265 const char *rule = /* set rule to "Invalid" for internal operands */
266 strcmp(mList._opcode,mList._resultStr) ? mList._opcode : "Invalid";
267
268 // If this rule produces an operand which has associated chain rules,
269 // update the operands with the chain rule + this rule cost & this rule.
270 chain_rule(fp, spaces6, mList._resultStr, cost, rule, operands_chained_from, status);
271
272 // Close the child-and-predicate-test braces
273 fprintf(fp, " }\n");
274
275 }
276
277
278 //---------------------------expand_opclass------------------------------------
279 // Chain from one result_type to all other members of its operand class
280 void ArchDesc::expand_opclass(FILE *fp, const char *indent, const Expr *cost,
281 const char *result_type, ProductionState &status) {
282 const Form *form = _globalNames[result_type];
283 OperandForm *op = form ? form->is_operand() : NULL;
284 if( op && op->_classes.count() > 0 ) {
285 if( debug_output ) { fprintf(fp, "// expand operand classes for operand: %s \n", (char *)op->_ident ); } // %%%%% Explanation
286 // Iterate through all operand classes which include this operand
287 op->_classes.reset();
288 const char *oclass;
289 // Expr *cCost = new Expr(cost);
290 while( (oclass = op->_classes.iter()) != NULL )
291 // Check against other match costs, and update cost & rule vectors
292 cost_check(fp, indent, ArchDesc::getMachOperEnum(oclass), cost, result_type, status);
293 }
294 }
295
296 //---------------------------chain_rule----------------------------------------
297 // Starting at 'operand', check if we know how to automatically generate other results
298 void ArchDesc::chain_rule(FILE *fp, const char *indent, const char *operand,
299 const Expr *icost, const char *irule, Dict &operands_chained_from, ProductionState &status) {
300
301 // Check if we have already generated chains from this starting point
302 if( operands_chained_from[operand] != NULL ) {
303 return;
304 } else {
305 operands_chained_from.Insert( operand, operand);
306 }
307 if( debug_output ) { fprintf(fp, "// chain rules starting from: %s and %s \n", (char *)operand, (char *)irule); } // %%%%% Explanation
308
309 ChainList *lst = (ChainList *)_chainRules[operand];
310 if (lst) {
311 // printf("\nChain from <%s> at cost #%s\n",operand, icost ? icost : "_");
312 const char *result, *cost, *rule;
313 for(lst->reset(); (lst->iter(result,cost,rule)) == true; ) {
314 // Do not generate operands that are already available
315 if( operands_chained_from[result] != NULL ) {
316 continue;
317 } else {
318 // Compute the cost for previous match + chain_rule_cost
319 // total_cost = icost + cost;
320 Expr *total_cost = icost->clone(); // icost + cost
321 total_cost->add(cost, *this);
322
323 // Check for transitive chain rules
324 Form *form = (Form *)_globalNames[rule];
325 if ( ! form->is_instruction()) {
326 // printf(" result=%s cost=%s rule=%s\n", result, total_cost, rule);
327 // Check against other match costs, and update cost & rule vectors
328 const char *reduce_rule = strcmp(irule,"Invalid") ? irule : rule;
329 cost_check(fp, indent, ArchDesc::getMachOperEnum(result), total_cost, reduce_rule, status);
330 chain_rule(fp, indent, result, total_cost, irule, operands_chained_from, status);
331 } else {
332 // printf(" result=%s cost=%s rule=%s\n", result, total_cost, rule);
333 // Check against other match costs, and update cost & rule vectors
334 cost_check(fp, indent, ArchDesc::getMachOperEnum(result), total_cost, rule, status);
335 chain_rule(fp, indent, result, total_cost, rule, operands_chained_from, status);
336 }
337
338 // If this is a member of an operand class, update class cost & rule
339 expand_opclass( fp, indent, total_cost, result, status );
340 }
341 }
342 }
343 }
344
345 //---------------------------prune_matchlist-----------------------------------
346 // Check for duplicate entries in a matchlist, and prune out the higher cost
347 // entry.
348 void ArchDesc::prune_matchlist(Dict &minimize, MatchList &mlist) {
349
350 }
351
352 //---------------------------buildDFA------------------------------------------
353 // DFA is a large switch with case statements for each ideal opcode encountered
354 // in any match rule in the ad file. Each case has a series of if's to handle
355 // the match or fail decisions. The matches test the cost function of that
356 // rule, and prune any cases which are higher cost for the same reduction.
357 // In order to generate the DFA we walk the table of ideal opcode/MatchList
358 // pairs generated by the ADLC front end to build the contents of the case
359 // statements (a series of if statements).
360 void ArchDesc::buildDFA(FILE* fp) {
361 int i;
362 // Remember operands that are the starting points for chain rules.
363 // Prevent cycles by checking if we have already generated chain.
364 Dict operands_chained_from(cmpstr, hashstr, Form::arena);
365
366 // Hash inputs to match rules so that final DFA contains only one entry for
367 // each match pattern which is the low cost entry.
368 Dict minimize(cmpstr, hashstr, Form::arena);
369
370 // Track status of dfa for each resulting production
371 // reset for each ideal root.
372 ProductionState status(Form::arena);
373
374 // Output the start of the DFA method into the output file
375
376 fprintf(fp, "\n");
377 fprintf(fp, "//------------------------- Source -----------------------------------------\n");
378 // Do not put random source code into the DFA.
379 // If there are constants which need sharing, put them in "source_hpp" forms.
380 // _source.output(fp);
381 fprintf(fp, "\n");
382 fprintf(fp, "//------------------------- Attributes -------------------------------------\n");
383 _attributes.output(fp);
384 fprintf(fp, "\n");
385 fprintf(fp, "//------------------------- Macros -----------------------------------------\n");
386 // #define DFA_PRODUCTION(result, rule, cost)\
387 // _cost[ (result) ] = cost; _rule[ (result) ] = rule;
388 fprintf(fp, "#define %s(result, rule, cost)\\\n", dfa_production);
389 fprintf(fp, " _cost[ (result) ] = cost; _rule[ (result) ] = rule;\n");
390 fprintf(fp, "\n");
391
392 // #define DFA_PRODUCTION__SET_VALID(result, rule, cost)\
393 // DFA_PRODUCTION( (result), (rule), (cost) ); STATE__SET_VALID( (result) );
394 fprintf(fp, "#define %s(result, rule, cost)\\\n", dfa_production_set_valid);
395 fprintf(fp, " %s( (result), (rule), (cost) ); STATE__SET_VALID( (result) );\n", dfa_production);
396 fprintf(fp, "\n");
397
398 fprintf(fp, "//------------------------- DFA --------------------------------------------\n");
399
400 fprintf(fp,
401 "// DFA is a large switch with case statements for each ideal opcode encountered\n"
402 "// in any match rule in the ad file. Each case has a series of if's to handle\n"
403 "// the match or fail decisions. The matches test the cost function of that\n"
404 "// rule, and prune any cases which are higher cost for the same reduction.\n"
405 "// In order to generate the DFA we walk the table of ideal opcode/MatchList\n"
406 "// pairs generated by the ADLC front end to build the contents of the case\n"
407 "// statements (a series of if statements).\n"
408 );
409 fprintf(fp, "\n");
410 fprintf(fp, "\n");
411 if (_dfa_small) {
412 // Now build the individual routines just like the switch entries in large version
413 // Iterate over the table of MatchLists, start at first valid opcode of 1
414 for (i = 1; i < _last_opcode; i++) {
415 if (_mlistab[i] == NULL) continue;
416 // Generate the routine header statement for this opcode
417 fprintf(fp, "void State::_sub_Op_%s(const Node *n){\n", NodeClassNames[i]);
418 // Generate body. Shared for both inline and out-of-line version
419 gen_dfa_state_body(fp, minimize, status, operands_chained_from, i);
420 // End of routine
421 fprintf(fp, "}\n");
422 }
423 }
424 fprintf(fp, "bool State::DFA");
425 fprintf(fp, "(int opcode, const Node *n) {\n");
426 fprintf(fp, " switch(opcode) {\n");
427
428 // Iterate over the table of MatchLists, start at first valid opcode of 1
429 for (i = 1; i < _last_opcode; i++) {
430 if (_mlistab[i] == NULL) continue;
431 // Generate the case statement for this opcode
432 if (_dfa_small) {
433 fprintf(fp, " case Op_%s: { _sub_Op_%s(n);\n", NodeClassNames[i], NodeClassNames[i]);
434 } else {
435 fprintf(fp, " case Op_%s: {\n", NodeClassNames[i]);
436 // Walk the list, compacting it
437 gen_dfa_state_body(fp, minimize, status, operands_chained_from, i);
438 }
439 // Print the "break"
440 fprintf(fp, " break;\n");
441 fprintf(fp, " }\n");
442 }
443
444 // Generate the default case for switch(opcode)
445 fprintf(fp, " \n");
446 fprintf(fp, " default:\n");
447 fprintf(fp, " tty->print(\"Default case invoked for: \\n\");\n");
448 fprintf(fp, " tty->print(\" opcode = %cd, \\\"%cs\\\"\\n\", opcode, NodeClassNames[opcode]);\n", '%', '%');
449 fprintf(fp, " return false;\n");
450 fprintf(fp, " }\n");
451
452 // Return status, indicating a successful match.
453 fprintf(fp, " return true;\n");
454 // Generate the closing brace for method Matcher::DFA
455 fprintf(fp, "}\n");
456 Expr::check_buffers();
457 }
458
459
460 class dfa_shared_preds {
461 enum { count = 4 };
462
463 static bool _found[count];
464 static const char* _type [count];
465 static const char* _var [count];
466 static const char* _pred [count];
467
468 static void check_index(int index) { assert( 0 <= index && index < count, "Invalid index"); }
469
470 // Confirm that this is a separate sub-expression.
471 // Only need to catch common cases like " ... && shared ..."
472 // and avoid hazardous ones like "...->shared"
473 static bool valid_loc(char *pred, char *shared) {
474 // start of predicate is valid
475 if( shared == pred ) return true;
476
477 // Check previous character and recurse if needed
478 char *prev = shared - 1;
479 char c = *prev;
480 switch( c ) {
481 case ' ':
482 case '\n':
483 return dfa_shared_preds::valid_loc(pred, prev);
484 case '!':
485 case '(':
486 case '<':
487 case '=':
488 return true;
489 case '"': // such as: #line 10 "myfile.ad"\n mypredicate
490 return true;
491 case '|':
492 if( prev != pred && *(prev-1) == '|' ) return true;
493 case '&':
494 if( prev != pred && *(prev-1) == '&' ) return true;
495 default:
496 return false;
497 }
498
499 return false;
500 }
501
502 public:
503
504 static bool found(int index){ check_index(index); return _found[index]; }
505 static void set_found(int index, bool val) { check_index(index); _found[index] = val; }
506 static void reset_found() {
507 for( int i = 0; i < count; ++i ) { _found[i] = false; }
508 };
509
510 static const char* type(int index) { check_index(index); return _type[index]; }
511 static const char* var (int index) { check_index(index); return _var [index]; }
512 static const char* pred(int index) { check_index(index); return _pred[index]; }
513
514 // Check each predicate in the MatchList for common sub-expressions
515 static void cse_matchlist(MatchList *matchList) {
516 for( MatchList *mList = matchList; mList != NULL; mList = mList->get_next() ) {
517 Predicate* predicate = mList->get_pred_obj();
518 char* pred = mList->get_pred();
519 if( pred != NULL ) {
520 for(int index = 0; index < count; ++index ) {
521 const char *shared_pred = dfa_shared_preds::pred(index);
522 const char *shared_pred_var = dfa_shared_preds::var(index);
523 bool result = dfa_shared_preds::cse_predicate(predicate, shared_pred, shared_pred_var);
524 if( result ) dfa_shared_preds::set_found(index, true);
525 }
526 }
527 }
528 }
529
530 // If the Predicate contains a common sub-expression, replace the Predicate's
531 // string with one that uses the variable name.
532 static bool cse_predicate(Predicate* predicate, const char *shared_pred, const char *shared_pred_var) {
533 bool result = false;
534 char *pred = predicate->_pred;
535 if( pred != NULL ) {
536 char *new_pred = pred;
537 for( char *shared_pred_loc = strstr(new_pred, shared_pred);
538 shared_pred_loc != NULL && dfa_shared_preds::valid_loc(new_pred,shared_pred_loc);
539 shared_pred_loc = strstr(new_pred, shared_pred) ) {
540 // Do not modify the original predicate string, it is shared
541 if( new_pred == pred ) {
542 new_pred = strdup(pred);
543 shared_pred_loc = strstr(new_pred, shared_pred);
544 }
545 // Replace shared_pred with variable name
546 strncpy(shared_pred_loc, shared_pred_var, strlen(shared_pred_var));
547 }
548 // Install new predicate
549 if( new_pred != pred ) {
550 predicate->_pred = new_pred;
551 result = true;
552 }
553 }
554 return result;
555 }
556
557 // Output the hoisted common sub-expression if we found it in predicates
558 static void generate_cse(FILE *fp) {
559 for(int j = 0; j < count; ++j ) {
560 if( dfa_shared_preds::found(j) ) {
561 const char *shared_pred_type = dfa_shared_preds::type(j);
562 const char *shared_pred_var = dfa_shared_preds::var(j);
563 const char *shared_pred = dfa_shared_preds::pred(j);
564 fprintf(fp, " %s %s = %s;\n", shared_pred_type, shared_pred_var, shared_pred);
565 }
566 }
567 }
568 };
569 // shared predicates, _var and _pred entry should be the same length
570 bool dfa_shared_preds::_found[dfa_shared_preds::count]
571 = { false, false, false, false };
572 const char* dfa_shared_preds::_type[dfa_shared_preds::count]
573 = { "int", "jlong", "intptr_t", "bool" };
574 const char* dfa_shared_preds::_var [dfa_shared_preds::count]
575 = { "_n_get_int__", "_n_get_long__", "_n_get_intptr_t__", "Compile__current____select_24_bit_instr__" };
576 const char* dfa_shared_preds::_pred[dfa_shared_preds::count]
577 = { "n->get_int()", "n->get_long()", "n->get_intptr_t()", "Compile::current()->select_24_bit_instr()" };
578
579
580 void ArchDesc::gen_dfa_state_body(FILE* fp, Dict &minimize, ProductionState &status, Dict &operands_chained_from, int i) {
581 // Start the body of each Op_XXX sub-dfa with a clean state.
582 status.initialize();
583
584 // Walk the list, compacting it
585 MatchList* mList = _mlistab[i];
586 do {
587 // Hash each entry using inputs as key and pointer as data.
588 // If there is already an entry, keep the one with lower cost, and
589 // remove the other one from the list.
590 prune_matchlist(minimize, *mList);
591 // Iterate
592 mList = mList->get_next();
593 } while(mList != NULL);
594
595 // Hoist previously specified common sub-expressions out of predicates
596 dfa_shared_preds::reset_found();
597 dfa_shared_preds::cse_matchlist(_mlistab[i]);
598 dfa_shared_preds::generate_cse(fp);
599
600 mList = _mlistab[i];
601
602 // Walk the list again, generating code
603 do {
604 // Each match can generate its own chains
605 operands_chained_from.Clear();
606 gen_match(fp, *mList, status, operands_chained_from);
607 mList = mList->get_next();
608 } while(mList != NULL);
609 // Fill in any chain rules which add instructions
610 // These can generate their own chains as well.
611 operands_chained_from.Clear(); //
612 if( debug_output1 ) { fprintf(fp, "// top level chain rules for: %s \n", (char *)NodeClassNames[i]); } // %%%%% Explanation
613 const Expr *zeroCost = new Expr("0");
614 chain_rule(fp, " ", (char *)NodeClassNames[i], zeroCost, "Invalid",
615 operands_chained_from, status);
616 }
617
618
619
620 //------------------------------Expr------------------------------------------
621 Expr *Expr::_unknown_expr = NULL;
622 char Expr::string_buffer[STRING_BUFFER_LENGTH];
623 char Expr::external_buffer[STRING_BUFFER_LENGTH];
624 bool Expr::_init_buffers = Expr::init_buffers();
625
626 Expr::Expr() {
627 _external_name = NULL;
628 _expr = "Invalid_Expr";
629 _min_value = Expr::Max;
630 _max_value = Expr::Zero;
631 }
632 Expr::Expr(const char *cost) {
633 _external_name = NULL;
634
635 int intval = 0;
636 if( cost == NULL ) {
637 _expr = "0";
638 _min_value = Expr::Zero;
639 _max_value = Expr::Zero;
640 }
641 else if( ADLParser::is_int_token(cost, intval) ) {
642 _expr = cost;
643 _min_value = intval;
644 _max_value = intval;
645 }
646 else {
647 assert( strcmp(cost,"0") != 0, "Recognize string zero as an int");
648 _expr = cost;
649 _min_value = Expr::Zero;
650 _max_value = Expr::Max;
651 }
652 }
653
654 Expr::Expr(const char *name, const char *expression, int min_value, int max_value) {
655 _external_name = name;
656 _expr = expression ? expression : name;
657 _min_value = min_value;
658 _max_value = max_value;
659 assert(_min_value >= 0 && _min_value <= Expr::Max, "value out of range");
660 assert(_max_value >= 0 && _max_value <= Expr::Max, "value out of range");
661 }
662
663 Expr *Expr::clone() const {
664 Expr *cost = new Expr();
665 cost->_external_name = _external_name;
666 cost->_expr = _expr;
667 cost->_min_value = _min_value;
668 cost->_max_value = _max_value;
669
670 return cost;
671 }
672
673 void Expr::add(const Expr *c) {
674 // Do not update fields until all computation is complete
675 const char *external = compute_external(this, c);
676 const char *expr = compute_expr(this, c);
677 int min_value = compute_min (this, c);
678 int max_value = compute_max (this, c);
679
680 _external_name = external;
681 _expr = expr;
682 _min_value = min_value;
683 _max_value = max_value;
684 }
685
686 void Expr::add(const char *c) {
687 Expr *cost = new Expr(c);
688 add(cost);
689 }
690
691 void Expr::add(const char *c, ArchDesc &AD) {
692 const Expr *e = AD.globalDefs()[c];
693 if( e != NULL ) {
694 // use the value of 'c' defined in <arch>.ad
695 add(e);
696 } else {
697 Expr *cost = new Expr(c);
698 add(cost);
699 }
700 }
701
702 const char *Expr::compute_external(const Expr *c1, const Expr *c2) {
703 const char * result = NULL;
704
705 // Preserve use of external name which has a zero value
706 if( c1->_external_name != NULL ) {
707 sprintf( string_buffer, "%s", c1->as_string());
708 if( !c2->is_zero() ) {
709 strcat( string_buffer, "+");
710 strcat( string_buffer, c2->as_string());
711 }
712 result = strdup(string_buffer);
713 }
714 else if( c2->_external_name != NULL ) {
715 if( !c1->is_zero() ) {
716 sprintf( string_buffer, "%s", c1->as_string());
717 strcat( string_buffer, " + ");
718 } else {
719 string_buffer[0] = '\0';
720 }
721 strcat( string_buffer, c2->_external_name );
722 result = strdup(string_buffer);
723 }
724 return result;
725 }
726
727 const char *Expr::compute_expr(const Expr *c1, const Expr *c2) {
728 if( !c1->is_zero() ) {
729 sprintf( string_buffer, "%s", c1->_expr);
730 if( !c2->is_zero() ) {
731 strcat( string_buffer, "+");
732 strcat( string_buffer, c2->_expr);
733 }
734 }
735 else if( !c2->is_zero() ) {
736 sprintf( string_buffer, "%s", c2->_expr);
737 }
738 else {
739 sprintf( string_buffer, "0");
740 }
741 char *cost = strdup(string_buffer);
742
743 return cost;
744 }
745
746 int Expr::compute_min(const Expr *c1, const Expr *c2) {
747 int result = c1->_min_value + c2->_min_value;
748 assert( result >= 0, "Invalid cost computation");
749
750 return result;
751 }
752
753 int Expr::compute_max(const Expr *c1, const Expr *c2) {
754 int result = c1->_max_value + c2->_max_value;
755 if( result < 0 ) { // check for overflow
756 result = Expr::Max;
757 }
758
759 return result;
760 }
761
762 void Expr::print() const {
763 if( _external_name != NULL ) {
764 printf(" %s == (%s) === [%d, %d]\n", _external_name, _expr, _min_value, _max_value);
765 } else {
766 printf(" %s === [%d, %d]\n", _expr, _min_value, _max_value);
767 }
768 }
769
770 void Expr::print_define(FILE *fp) const {
771 assert( _external_name != NULL, "definition does not have a name");
772 assert( _min_value == _max_value, "Expect user definitions to have constant value");
773 fprintf(fp, "#define %s (%s) \n", _external_name, _expr);
774 fprintf(fp, "// value == %d \n", _min_value);
775 }
776
777 void Expr::print_assert(FILE *fp) const {
778 assert( _external_name != NULL, "definition does not have a name");
779 assert( _min_value == _max_value, "Expect user definitions to have constant value");
780 fprintf(fp, " assert( %s == %d, \"Expect (%s) to equal %d\");\n", _external_name, _min_value, _expr, _min_value);
781 }
782
783 Expr *Expr::get_unknown() {
784 if( Expr::_unknown_expr == NULL ) {
785 Expr::_unknown_expr = new Expr();
786 }
787
788 return Expr::_unknown_expr;
789 }
790
791 bool Expr::init_buffers() {
792 // Fill buffers with 0
793 for( int i = 0; i < STRING_BUFFER_LENGTH; ++i ) {
794 external_buffer[i] = '\0';
795 string_buffer[i] = '\0';
796 }
797
798 return true;
799 }
800
801 bool Expr::check_buffers() {
802 // returns 'true' if buffer use may have overflowed
803 bool ok = true;
804 for( int i = STRING_BUFFER_LENGTH - 100; i < STRING_BUFFER_LENGTH; ++i) {
805 if( external_buffer[i] != '\0' || string_buffer[i] != '\0' ) {
806 ok = false;
807 assert( false, "Expr:: Buffer overflow");
808 }
809 }
810
811 return ok;
812 }
813
814
815 //------------------------------ExprDict---------------------------------------
816 // Constructor
817 ExprDict::ExprDict( CmpKey cmp, Hash hash, Arena *arena )
818 : _expr(cmp, hash, arena), _defines() {
819 }
820 ExprDict::~ExprDict() {
821 }
822
823 // Return # of name-Expr pairs in dict
824 int ExprDict::Size(void) const {
825 return _expr.Size();
826 }
827
828 // define inserts the given key-value pair into the dictionary,
829 // and records the name in order for later output, ...
830 const Expr *ExprDict::define(const char *name, Expr *expr) {
831 const Expr *old_expr = (*this)[name];
832 assert(old_expr == NULL, "Implementation does not support redefinition");
833
834 _expr.Insert(name, expr);
835 _defines.addName(name);
836
837 return old_expr;
838 }
839
840 // Insert inserts the given key-value pair into the dictionary. The prior
841 // value of the key is returned; NULL if the key was not previously defined.
842 const Expr *ExprDict::Insert(const char *name, Expr *expr) {
843 return (Expr*)_expr.Insert((void*)name, (void*)expr);
844 }
845
846 // Finds the value of a given key; or NULL if not found.
847 // The dictionary is NOT changed.
848 const Expr *ExprDict::operator [](const char *name) const {
849 return (Expr*)_expr[name];
850 }
851
852 void ExprDict::print_defines(FILE *fp) {
853 fprintf(fp, "\n");
854 const char *name = NULL;
855 for( _defines.reset(); (name = _defines.iter()) != NULL; ) {
856 const Expr *expr = (const Expr*)_expr[name];
857 assert( expr != NULL, "name in ExprDict without matching Expr in dictionary");
858 expr->print_define(fp);
859 }
860 }
861 void ExprDict::print_asserts(FILE *fp) {
862 fprintf(fp, "\n");
863 fprintf(fp, " // Following assertions generated from definition section\n");
864 const char *name = NULL;
865 for( _defines.reset(); (name = _defines.iter()) != NULL; ) {
866 const Expr *expr = (const Expr*)_expr[name];
867 assert( expr != NULL, "name in ExprDict without matching Expr in dictionary");
868 expr->print_assert(fp);
869 }
870 }
871
872 // Print out the dictionary contents as key-value pairs
873 static void dumpekey(const void* key) { fprintf(stdout, "%s", (char*) key); }
874 static void dumpexpr(const void* expr) { fflush(stdout); ((Expr*)expr)->print(); }
875
876 void ExprDict::dump() {
877 _expr.print(dumpekey, dumpexpr);
878 }
879
880
881 //------------------------------ExprDict::private------------------------------
882 // Disable public use of constructor, copy-ctor, operator =, operator ==
883 ExprDict::ExprDict( ) : _expr(cmpkey,hashkey), _defines() {
884 assert( false, "NotImplemented");
885 }
886 ExprDict::ExprDict( const ExprDict & ) : _expr(cmpkey,hashkey), _defines() {
887 assert( false, "NotImplemented");
888 }
889 ExprDict &ExprDict::operator =( const ExprDict &rhs) {
890 assert( false, "NotImplemented");
891 _expr = rhs._expr;
892 return *this;
893 }
894 // == compares two dictionaries; they must have the same keys (their keys
895 // must match using CmpKey) and they must have the same values (pointer
896 // comparison). If so 1 is returned, if not 0 is returned.
897 bool ExprDict::operator ==(const ExprDict &d) const {
898 assert( false, "NotImplemented");
899 return false;
900 }
901
902
903 //------------------------------Production-------------------------------------
904 Production::Production(const char *result, const char *constraint, const char *valid) {
905 initialize();
906 _result = result;
907 _constraint = constraint;
908 _valid = valid;
909 }
910
911 void Production::initialize() {
912 _result = NULL;
913 _constraint = NULL;
914 _valid = knownInvalid;
915 _cost_lb = Expr::get_unknown();
916 _cost_ub = Expr::get_unknown();
917 }
918
919 void Production::print() {
920 printf("%s", (_result == NULL ? "NULL" : _result ) );
921 printf("%s", (_constraint == NULL ? "NULL" : _constraint ) );
922 printf("%s", (_valid == NULL ? "NULL" : _valid ) );
923 _cost_lb->print();
924 _cost_ub->print();
925 }
926
927
928 //------------------------------ProductionState--------------------------------
929 void ProductionState::initialize() {
930 _constraint = noConstraint;
931
932 // reset each Production currently in the dictionary
933 DictI iter( &_production );
934 const void *x, *y = NULL;
935 for( ; iter.test(); ++iter) {
936 x = iter._key;
937 y = iter._value;
938 Production *p = (Production*)y;
939 if( p != NULL ) {
940 p->initialize();
941 }
942 }
943 }
944
945 Production *ProductionState::getProduction(const char *result) {
946 Production *p = (Production *)_production[result];
947 if( p == NULL ) {
948 p = new Production(result, _constraint, knownInvalid);
949 _production.Insert(result, p);
950 }
951
952 return p;
953 }
954
955 void ProductionState::set_constraint(const char *constraint) {
956 _constraint = constraint;
957 }
958
959 const char *ProductionState::valid(const char *result) {
960 return getProduction(result)->valid();
961 }
962
963 void ProductionState::set_valid(const char *result) {
964 Production *p = getProduction(result);
965
966 // Update valid as allowed by current constraints
967 if( _constraint == noConstraint ) {
968 p->_valid = knownValid;
969 } else {
970 if( p->_valid != knownValid ) {
971 p->_valid = unknownValid;
972 }
973 }
974 }
975
976 Expr *ProductionState::cost_lb(const char *result) {
977 return getProduction(result)->cost_lb();
978 }
979
980 Expr *ProductionState::cost_ub(const char *result) {
981 return getProduction(result)->cost_ub();
982 }
983
984 void ProductionState::set_cost_bounds(const char *result, const Expr *cost, bool has_state_check, bool has_cost_check) {
985 Production *p = getProduction(result);
986
987 if( p->_valid == knownInvalid ) {
988 // Our cost bounds are not unknown, just not defined.
989 p->_cost_lb = cost->clone();
990 p->_cost_ub = cost->clone();
991 } else if (has_state_check || _constraint != noConstraint) {
992 // The production is protected by a condition, so
993 // the cost bounds may expand.
994 // _cost_lb = min(cost, _cost_lb)
995 if( cost->less_than_or_equal(p->_cost_lb) ) {
996 p->_cost_lb = cost->clone();
997 }
998 // _cost_ub = max(cost, _cost_ub)
999 if( p->_cost_ub->less_than_or_equal(cost) ) {
1000 p->_cost_ub = cost->clone();
1001 }
1002 } else if (has_cost_check) {
1003 // The production has no condition check, but does
1004 // have a cost check that could reduce the upper
1005 // and/or lower bound.
1006 // _cost_lb = min(cost, _cost_lb)
1007 if( cost->less_than_or_equal(p->_cost_lb) ) {
1008 p->_cost_lb = cost->clone();
1009 }
1010 // _cost_ub = min(cost, _cost_ub)
1011 if( cost->less_than_or_equal(p->_cost_ub) ) {
1012 p->_cost_ub = cost->clone();
1013 }
1014 } else {
1015 // The costs are unconditionally set.
1016 p->_cost_lb = cost->clone();
1017 p->_cost_ub = cost->clone();
1018 }
1019
1020 }
1021
1022 // Print out the dictionary contents as key-value pairs
1023 static void print_key (const void* key) { fprintf(stdout, "%s", (char*) key); }
1024 static void print_production(const void* production) { fflush(stdout); ((Production*)production)->print(); }
1025
1026 void ProductionState::print() {
1027 _production.print(print_key, print_production);
1028 }