Mercurial > hg > graal-compiler
annotate src/cpu/x86/vm/c1_LinearScan_x86.cpp @ 2719:ae1c50a03297
Fixed regression.
author | Thomas Wuerthinger <thomas@wuerthinger.net> |
---|---|
date | Thu, 19 May 2011 16:26:32 +0200 |
parents | f95d63e2154a |
children | 6759698e3140 |
rev | line source |
---|---|
0 | 1 /* |
1972 | 2 * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved. |
0 | 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. | |
18 * | |
1552
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19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
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20 * or visit www.oracle.com if you need additional information or have any |
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21 * questions. |
0 | 22 * |
23 */ | |
24 | |
1972 | 25 #include "precompiled.hpp" |
26 #include "c1/c1_Instruction.hpp" | |
27 #include "c1/c1_LinearScan.hpp" | |
28 #include "utilities/bitMap.inline.hpp" | |
0 | 29 |
30 | |
31 //---------------------------------------------------------------------- | |
32 // Allocation of FPU stack slots (Intel x86 only) | |
33 //---------------------------------------------------------------------- | |
34 | |
35 void LinearScan::allocate_fpu_stack() { | |
36 // First compute which FPU registers are live at the start of each basic block | |
37 // (To minimize the amount of work we have to do if we have to merge FPU stacks) | |
38 if (ComputeExactFPURegisterUsage) { | |
39 Interval* intervals_in_register, *intervals_in_memory; | |
40 create_unhandled_lists(&intervals_in_register, &intervals_in_memory, is_in_fpu_register, NULL); | |
41 | |
42 // ignore memory intervals by overwriting intervals_in_memory | |
43 // the dummy interval is needed to enforce the walker to walk until the given id: | |
44 // without it, the walker stops when the unhandled-list is empty -> live information | |
45 // beyond this point would be incorrect. | |
46 Interval* dummy_interval = new Interval(any_reg); | |
47 dummy_interval->add_range(max_jint - 2, max_jint - 1); | |
48 dummy_interval->set_next(Interval::end()); | |
49 intervals_in_memory = dummy_interval; | |
50 | |
51 IntervalWalker iw(this, intervals_in_register, intervals_in_memory); | |
52 | |
53 const int num_blocks = block_count(); | |
54 for (int i = 0; i < num_blocks; i++) { | |
55 BlockBegin* b = block_at(i); | |
56 | |
57 // register usage is only needed for merging stacks -> compute only | |
58 // when more than one predecessor. | |
59 // the block must not have any spill moves at the beginning (checked by assertions) | |
60 // spill moves would use intervals that are marked as handled and so the usage bit | |
61 // would been set incorrectly | |
62 | |
63 // NOTE: the check for number_of_preds > 1 is necessary. A block with only one | |
64 // predecessor may have spill moves at the begin of the block. | |
65 // If an interval ends at the current instruction id, it is not possible | |
66 // to decide if the register is live or not at the block begin -> the | |
67 // register information would be incorrect. | |
68 if (b->number_of_preds() > 1) { | |
69 int id = b->first_lir_instruction_id(); | |
70 BitMap regs(FrameMap::nof_fpu_regs); | |
71 regs.clear(); | |
72 | |
73 iw.walk_to(id); // walk after the first instruction (always a label) of the block | |
74 assert(iw.current_position() == id, "did not walk completely to id"); | |
75 | |
76 // Only consider FPU values in registers | |
77 Interval* interval = iw.active_first(fixedKind); | |
78 while (interval != Interval::end()) { | |
79 int reg = interval->assigned_reg(); | |
80 assert(reg >= pd_first_fpu_reg && reg <= pd_last_fpu_reg, "no fpu register"); | |
81 assert(interval->assigned_regHi() == -1, "must not have hi register (doubles stored in one register)"); | |
82 assert(interval->from() <= id && id < interval->to(), "interval out of range"); | |
83 | |
84 #ifndef PRODUCT | |
85 if (TraceFPURegisterUsage) { | |
86 tty->print("fpu reg %d is live because of ", reg - pd_first_fpu_reg); interval->print(); | |
87 } | |
88 #endif | |
89 | |
90 regs.set_bit(reg - pd_first_fpu_reg); | |
91 interval = interval->next(); | |
92 } | |
93 | |
94 b->set_fpu_register_usage(regs); | |
95 | |
96 #ifndef PRODUCT | |
97 if (TraceFPURegisterUsage) { | |
98 tty->print("FPU regs for block %d, LIR instr %d): ", b->block_id(), id); regs.print_on(tty); tty->print_cr(""); | |
99 } | |
100 #endif | |
101 } | |
102 } | |
103 } | |
104 | |
105 FpuStackAllocator alloc(ir()->compilation(), this); | |
106 _fpu_stack_allocator = &alloc; | |
107 alloc.allocate(); | |
108 _fpu_stack_allocator = NULL; | |
109 } | |
110 | |
111 | |
112 FpuStackAllocator::FpuStackAllocator(Compilation* compilation, LinearScan* allocator) | |
113 : _compilation(compilation) | |
114 , _lir(NULL) | |
115 , _pos(-1) | |
116 , _allocator(allocator) | |
117 , _sim(compilation) | |
118 , _temp_sim(compilation) | |
119 {} | |
120 | |
121 void FpuStackAllocator::allocate() { | |
122 int num_blocks = allocator()->block_count(); | |
123 for (int i = 0; i < num_blocks; i++) { | |
124 // Set up to process block | |
125 BlockBegin* block = allocator()->block_at(i); | |
126 intArray* fpu_stack_state = block->fpu_stack_state(); | |
127 | |
128 #ifndef PRODUCT | |
129 if (TraceFPUStack) { | |
130 tty->cr(); | |
131 tty->print_cr("------- Begin of new Block %d -------", block->block_id()); | |
132 } | |
133 #endif | |
134 | |
135 assert(fpu_stack_state != NULL || | |
136 block->end()->as_Base() != NULL || | |
137 block->is_set(BlockBegin::exception_entry_flag), | |
138 "FPU stack state must be present due to linear-scan order for FPU stack allocation"); | |
139 // note: exception handler entries always start with an empty fpu stack | |
140 // because stack merging would be too complicated | |
141 | |
142 if (fpu_stack_state != NULL) { | |
143 sim()->read_state(fpu_stack_state); | |
144 } else { | |
145 sim()->clear(); | |
146 } | |
147 | |
148 #ifndef PRODUCT | |
149 if (TraceFPUStack) { | |
150 tty->print("Reading FPU state for block %d:", block->block_id()); | |
151 sim()->print(); | |
152 tty->cr(); | |
153 } | |
154 #endif | |
155 | |
156 allocate_block(block); | |
157 CHECK_BAILOUT(); | |
158 } | |
159 } | |
160 | |
161 void FpuStackAllocator::allocate_block(BlockBegin* block) { | |
162 bool processed_merge = false; | |
163 LIR_OpList* insts = block->lir()->instructions_list(); | |
164 set_lir(block->lir()); | |
165 set_pos(0); | |
166 | |
167 | |
168 // Note: insts->length() may change during loop | |
169 while (pos() < insts->length()) { | |
170 LIR_Op* op = insts->at(pos()); | |
171 _debug_information_computed = false; | |
172 | |
173 #ifndef PRODUCT | |
174 if (TraceFPUStack) { | |
175 op->print(); | |
176 } | |
177 check_invalid_lir_op(op); | |
178 #endif | |
179 | |
180 LIR_OpBranch* branch = op->as_OpBranch(); | |
181 LIR_Op1* op1 = op->as_Op1(); | |
182 LIR_Op2* op2 = op->as_Op2(); | |
183 LIR_OpCall* opCall = op->as_OpCall(); | |
184 | |
185 if (branch != NULL && branch->block() != NULL) { | |
186 if (!processed_merge) { | |
187 // propagate stack at first branch to a successor | |
188 processed_merge = true; | |
189 bool required_merge = merge_fpu_stack_with_successors(block); | |
190 | |
191 assert(!required_merge || branch->cond() == lir_cond_always, "splitting of critical edges should prevent FPU stack mismatches at cond branches"); | |
192 } | |
193 | |
194 } else if (op1 != NULL) { | |
195 handle_op1(op1); | |
196 } else if (op2 != NULL) { | |
197 handle_op2(op2); | |
198 } else if (opCall != NULL) { | |
199 handle_opCall(opCall); | |
200 } | |
201 | |
202 compute_debug_information(op); | |
203 | |
204 set_pos(1 + pos()); | |
205 } | |
206 | |
207 // Propagate stack when block does not end with branch | |
208 if (!processed_merge) { | |
209 merge_fpu_stack_with_successors(block); | |
210 } | |
211 } | |
212 | |
213 | |
214 void FpuStackAllocator::compute_debug_information(LIR_Op* op) { | |
215 if (!_debug_information_computed && op->id() != -1 && allocator()->has_info(op->id())) { | |
216 visitor.visit(op); | |
217 | |
218 // exception handling | |
219 if (allocator()->compilation()->has_exception_handlers()) { | |
220 XHandlers* xhandlers = visitor.all_xhandler(); | |
221 int n = xhandlers->length(); | |
222 for (int k = 0; k < n; k++) { | |
223 allocate_exception_handler(xhandlers->handler_at(k)); | |
224 } | |
225 } else { | |
226 assert(visitor.all_xhandler()->length() == 0, "missed exception handler"); | |
227 } | |
228 | |
229 // compute debug information | |
230 int n = visitor.info_count(); | |
231 assert(n > 0, "should not visit operation otherwise"); | |
232 | |
233 for (int j = 0; j < n; j++) { | |
234 CodeEmitInfo* info = visitor.info_at(j); | |
235 // Compute debug information | |
236 allocator()->compute_debug_info(info, op->id()); | |
237 } | |
238 } | |
239 _debug_information_computed = true; | |
240 } | |
241 | |
242 void FpuStackAllocator::allocate_exception_handler(XHandler* xhandler) { | |
243 if (!sim()->is_empty()) { | |
244 LIR_List* old_lir = lir(); | |
245 int old_pos = pos(); | |
246 intArray* old_state = sim()->write_state(); | |
247 | |
248 #ifndef PRODUCT | |
249 if (TraceFPUStack) { | |
250 tty->cr(); | |
251 tty->print_cr("------- begin of exception handler -------"); | |
252 } | |
253 #endif | |
254 | |
255 if (xhandler->entry_code() == NULL) { | |
256 // need entry code to clear FPU stack | |
257 LIR_List* entry_code = new LIR_List(_compilation); | |
258 entry_code->jump(xhandler->entry_block()); | |
259 xhandler->set_entry_code(entry_code); | |
260 } | |
261 | |
262 LIR_OpList* insts = xhandler->entry_code()->instructions_list(); | |
263 set_lir(xhandler->entry_code()); | |
264 set_pos(0); | |
265 | |
266 // Note: insts->length() may change during loop | |
267 while (pos() < insts->length()) { | |
268 LIR_Op* op = insts->at(pos()); | |
269 | |
270 #ifndef PRODUCT | |
271 if (TraceFPUStack) { | |
272 op->print(); | |
273 } | |
274 check_invalid_lir_op(op); | |
275 #endif | |
276 | |
277 switch (op->code()) { | |
278 case lir_move: | |
279 assert(op->as_Op1() != NULL, "must be LIR_Op1"); | |
280 assert(pos() != insts->length() - 1, "must not be last operation"); | |
281 | |
282 handle_op1((LIR_Op1*)op); | |
283 break; | |
284 | |
285 case lir_branch: | |
286 assert(op->as_OpBranch()->cond() == lir_cond_always, "must be unconditional branch"); | |
287 assert(pos() == insts->length() - 1, "must be last operation"); | |
288 | |
289 // remove all remaining dead registers from FPU stack | |
290 clear_fpu_stack(LIR_OprFact::illegalOpr); | |
291 break; | |
292 | |
293 default: | |
294 // other operations not allowed in exception entry code | |
295 ShouldNotReachHere(); | |
296 } | |
297 | |
298 set_pos(pos() + 1); | |
299 } | |
300 | |
301 #ifndef PRODUCT | |
302 if (TraceFPUStack) { | |
303 tty->cr(); | |
304 tty->print_cr("------- end of exception handler -------"); | |
305 } | |
306 #endif | |
307 | |
308 set_lir(old_lir); | |
309 set_pos(old_pos); | |
310 sim()->read_state(old_state); | |
311 } | |
312 } | |
313 | |
314 | |
315 int FpuStackAllocator::fpu_num(LIR_Opr opr) { | |
316 assert(opr->is_fpu_register() && !opr->is_xmm_register(), "shouldn't call this otherwise"); | |
317 return opr->is_single_fpu() ? opr->fpu_regnr() : opr->fpu_regnrLo(); | |
318 } | |
319 | |
320 int FpuStackAllocator::tos_offset(LIR_Opr opr) { | |
321 return sim()->offset_from_tos(fpu_num(opr)); | |
322 } | |
323 | |
324 | |
325 LIR_Opr FpuStackAllocator::to_fpu_stack(LIR_Opr opr) { | |
326 assert(opr->is_fpu_register() && !opr->is_xmm_register(), "shouldn't call this otherwise"); | |
327 | |
328 int stack_offset = tos_offset(opr); | |
329 if (opr->is_single_fpu()) { | |
330 return LIR_OprFact::single_fpu(stack_offset)->make_fpu_stack_offset(); | |
331 } else { | |
332 assert(opr->is_double_fpu(), "shouldn't call this otherwise"); | |
333 return LIR_OprFact::double_fpu(stack_offset)->make_fpu_stack_offset(); | |
334 } | |
335 } | |
336 | |
337 LIR_Opr FpuStackAllocator::to_fpu_stack_top(LIR_Opr opr, bool dont_check_offset) { | |
338 assert(opr->is_fpu_register() && !opr->is_xmm_register(), "shouldn't call this otherwise"); | |
339 assert(dont_check_offset || tos_offset(opr) == 0, "operand is not on stack top"); | |
340 | |
341 int stack_offset = 0; | |
342 if (opr->is_single_fpu()) { | |
343 return LIR_OprFact::single_fpu(stack_offset)->make_fpu_stack_offset(); | |
344 } else { | |
345 assert(opr->is_double_fpu(), "shouldn't call this otherwise"); | |
346 return LIR_OprFact::double_fpu(stack_offset)->make_fpu_stack_offset(); | |
347 } | |
348 } | |
349 | |
350 | |
351 | |
352 void FpuStackAllocator::insert_op(LIR_Op* op) { | |
353 lir()->insert_before(pos(), op); | |
354 set_pos(1 + pos()); | |
355 } | |
356 | |
357 | |
358 void FpuStackAllocator::insert_exchange(int offset) { | |
359 if (offset > 0) { | |
360 LIR_Op1* fxch_op = new LIR_Op1(lir_fxch, LIR_OprFact::intConst(offset), LIR_OprFact::illegalOpr); | |
361 insert_op(fxch_op); | |
362 sim()->swap(offset); | |
363 | |
364 #ifndef PRODUCT | |
365 if (TraceFPUStack) { | |
366 tty->print("Exchanged register: %d New state: ", sim()->get_slot(0)); sim()->print(); tty->cr(); | |
367 } | |
368 #endif | |
369 | |
370 } | |
371 } | |
372 | |
373 void FpuStackAllocator::insert_exchange(LIR_Opr opr) { | |
374 insert_exchange(tos_offset(opr)); | |
375 } | |
376 | |
377 | |
378 void FpuStackAllocator::insert_free(int offset) { | |
379 // move stack slot to the top of stack and then pop it | |
380 insert_exchange(offset); | |
381 | |
382 LIR_Op* fpop = new LIR_Op0(lir_fpop_raw); | |
383 insert_op(fpop); | |
384 sim()->pop(); | |
385 | |
386 #ifndef PRODUCT | |
387 if (TraceFPUStack) { | |
388 tty->print("Inserted pop New state: "); sim()->print(); tty->cr(); | |
389 } | |
390 #endif | |
391 } | |
392 | |
393 | |
394 void FpuStackAllocator::insert_free_if_dead(LIR_Opr opr) { | |
395 if (sim()->contains(fpu_num(opr))) { | |
396 int res_slot = tos_offset(opr); | |
397 insert_free(res_slot); | |
398 } | |
399 } | |
400 | |
401 void FpuStackAllocator::insert_free_if_dead(LIR_Opr opr, LIR_Opr ignore) { | |
402 if (fpu_num(opr) != fpu_num(ignore) && sim()->contains(fpu_num(opr))) { | |
403 int res_slot = tos_offset(opr); | |
404 insert_free(res_slot); | |
405 } | |
406 } | |
407 | |
408 void FpuStackAllocator::insert_copy(LIR_Opr from, LIR_Opr to) { | |
409 int offset = tos_offset(from); | |
410 LIR_Op1* fld = new LIR_Op1(lir_fld, LIR_OprFact::intConst(offset), LIR_OprFact::illegalOpr); | |
411 insert_op(fld); | |
412 | |
413 sim()->push(fpu_num(to)); | |
414 | |
415 #ifndef PRODUCT | |
416 if (TraceFPUStack) { | |
417 tty->print("Inserted copy (%d -> %d) New state: ", fpu_num(from), fpu_num(to)); sim()->print(); tty->cr(); | |
418 } | |
419 #endif | |
420 } | |
421 | |
422 void FpuStackAllocator::do_rename(LIR_Opr from, LIR_Opr to) { | |
423 sim()->rename(fpu_num(from), fpu_num(to)); | |
424 } | |
425 | |
426 void FpuStackAllocator::do_push(LIR_Opr opr) { | |
427 sim()->push(fpu_num(opr)); | |
428 } | |
429 | |
430 void FpuStackAllocator::pop_if_last_use(LIR_Op* op, LIR_Opr opr) { | |
431 assert(op->fpu_pop_count() == 0, "fpu_pop_count alredy set"); | |
432 assert(tos_offset(opr) == 0, "can only pop stack top"); | |
433 | |
434 if (opr->is_last_use()) { | |
435 op->set_fpu_pop_count(1); | |
436 sim()->pop(); | |
437 } | |
438 } | |
439 | |
440 void FpuStackAllocator::pop_always(LIR_Op* op, LIR_Opr opr) { | |
441 assert(op->fpu_pop_count() == 0, "fpu_pop_count alredy set"); | |
442 assert(tos_offset(opr) == 0, "can only pop stack top"); | |
443 | |
444 op->set_fpu_pop_count(1); | |
445 sim()->pop(); | |
446 } | |
447 | |
448 void FpuStackAllocator::clear_fpu_stack(LIR_Opr preserve) { | |
449 int result_stack_size = (preserve->is_fpu_register() && !preserve->is_xmm_register() ? 1 : 0); | |
450 while (sim()->stack_size() > result_stack_size) { | |
451 assert(!sim()->slot_is_empty(0), "not allowed"); | |
452 | |
453 if (result_stack_size == 0 || sim()->get_slot(0) != fpu_num(preserve)) { | |
454 insert_free(0); | |
455 } else { | |
456 // move "preserve" to bottom of stack so that all other stack slots can be popped | |
457 insert_exchange(sim()->stack_size() - 1); | |
458 } | |
459 } | |
460 } | |
461 | |
462 | |
463 void FpuStackAllocator::handle_op1(LIR_Op1* op1) { | |
464 LIR_Opr in = op1->in_opr(); | |
465 LIR_Opr res = op1->result_opr(); | |
466 | |
467 LIR_Opr new_in = in; // new operands relative to the actual fpu stack top | |
468 LIR_Opr new_res = res; | |
469 | |
470 // Note: this switch is processed for all LIR_Op1, regardless if they have FPU-arguments, | |
471 // so checks for is_float_kind() are necessary inside the cases | |
472 switch (op1->code()) { | |
473 | |
474 case lir_return: { | |
475 // FPU-Stack must only contain the (optional) fpu return value. | |
476 // All remaining dead values are popped from the stack | |
477 // If the input operand is a fpu-register, it is exchanged to the bottom of the stack | |
478 | |
479 clear_fpu_stack(in); | |
480 if (in->is_fpu_register() && !in->is_xmm_register()) { | |
481 new_in = to_fpu_stack_top(in); | |
482 } | |
483 | |
484 break; | |
485 } | |
486 | |
487 case lir_move: { | |
488 if (in->is_fpu_register() && !in->is_xmm_register()) { | |
489 if (res->is_xmm_register()) { | |
490 // move from fpu register to xmm register (necessary for operations that | |
491 // are not available in the SSE instruction set) | |
492 insert_exchange(in); | |
493 new_in = to_fpu_stack_top(in); | |
494 pop_always(op1, in); | |
495 | |
496 } else if (res->is_fpu_register() && !res->is_xmm_register()) { | |
497 // move from fpu-register to fpu-register: | |
498 // * input and result register equal: | |
499 // nothing to do | |
500 // * input register is last use: | |
501 // rename the input register to result register -> input register | |
502 // not present on fpu-stack afterwards | |
503 // * input register not last use: | |
504 // duplicate input register to result register to preserve input | |
505 // | |
506 // Note: The LIR-Assembler does not produce any code for fpu register moves, | |
507 // so input and result stack index must be equal | |
508 | |
509 if (fpu_num(in) == fpu_num(res)) { | |
510 // nothing to do | |
511 } else if (in->is_last_use()) { | |
512 insert_free_if_dead(res);//, in); | |
513 do_rename(in, res); | |
514 } else { | |
515 insert_free_if_dead(res); | |
516 insert_copy(in, res); | |
517 } | |
518 new_in = to_fpu_stack(res); | |
519 new_res = new_in; | |
520 | |
521 } else { | |
522 // move from fpu-register to memory | |
523 // input operand must be on top of stack | |
524 | |
525 insert_exchange(in); | |
526 | |
527 // create debug information here because afterwards the register may have been popped | |
528 compute_debug_information(op1); | |
529 | |
530 new_in = to_fpu_stack_top(in); | |
531 pop_if_last_use(op1, in); | |
532 } | |
533 | |
534 } else if (res->is_fpu_register() && !res->is_xmm_register()) { | |
535 // move from memory/constant to fpu register | |
536 // result is pushed on the stack | |
537 | |
538 insert_free_if_dead(res); | |
539 | |
540 // create debug information before register is pushed | |
541 compute_debug_information(op1); | |
542 | |
543 do_push(res); | |
544 new_res = to_fpu_stack_top(res); | |
545 } | |
546 break; | |
547 } | |
548 | |
549 case lir_neg: { | |
550 if (in->is_fpu_register() && !in->is_xmm_register()) { | |
551 assert(res->is_fpu_register() && !res->is_xmm_register(), "must be"); | |
552 assert(in->is_last_use(), "old value gets destroyed"); | |
553 | |
554 insert_free_if_dead(res, in); | |
555 insert_exchange(in); | |
556 new_in = to_fpu_stack_top(in); | |
557 | |
558 do_rename(in, res); | |
559 new_res = to_fpu_stack_top(res); | |
560 } | |
561 break; | |
562 } | |
563 | |
564 case lir_convert: { | |
565 Bytecodes::Code bc = op1->as_OpConvert()->bytecode(); | |
566 switch (bc) { | |
567 case Bytecodes::_d2f: | |
568 case Bytecodes::_f2d: | |
569 assert(res->is_fpu_register(), "must be"); | |
570 assert(in->is_fpu_register(), "must be"); | |
571 | |
572 if (!in->is_xmm_register() && !res->is_xmm_register()) { | |
573 // this is quite the same as a move from fpu-register to fpu-register | |
574 // Note: input and result operands must have different types | |
575 if (fpu_num(in) == fpu_num(res)) { | |
576 // nothing to do | |
577 new_in = to_fpu_stack(in); | |
578 } else if (in->is_last_use()) { | |
579 insert_free_if_dead(res);//, in); | |
580 new_in = to_fpu_stack(in); | |
581 do_rename(in, res); | |
582 } else { | |
583 insert_free_if_dead(res); | |
584 insert_copy(in, res); | |
585 new_in = to_fpu_stack_top(in, true); | |
586 } | |
587 new_res = to_fpu_stack(res); | |
588 } | |
589 | |
590 break; | |
591 | |
592 case Bytecodes::_i2f: | |
593 case Bytecodes::_l2f: | |
594 case Bytecodes::_i2d: | |
595 case Bytecodes::_l2d: | |
596 assert(res->is_fpu_register(), "must be"); | |
597 if (!res->is_xmm_register()) { | |
598 insert_free_if_dead(res); | |
599 do_push(res); | |
600 new_res = to_fpu_stack_top(res); | |
601 } | |
602 break; | |
603 | |
604 case Bytecodes::_f2i: | |
605 case Bytecodes::_d2i: | |
606 assert(in->is_fpu_register(), "must be"); | |
607 if (!in->is_xmm_register()) { | |
608 insert_exchange(in); | |
609 new_in = to_fpu_stack_top(in); | |
610 | |
611 // TODO: update registes of stub | |
612 } | |
613 break; | |
614 | |
615 case Bytecodes::_f2l: | |
616 case Bytecodes::_d2l: | |
617 assert(in->is_fpu_register(), "must be"); | |
618 if (!in->is_xmm_register()) { | |
619 insert_exchange(in); | |
620 new_in = to_fpu_stack_top(in); | |
621 pop_always(op1, in); | |
622 } | |
623 break; | |
624 | |
625 case Bytecodes::_i2l: | |
626 case Bytecodes::_l2i: | |
627 case Bytecodes::_i2b: | |
628 case Bytecodes::_i2c: | |
629 case Bytecodes::_i2s: | |
630 // no fpu operands | |
631 break; | |
632 | |
633 default: | |
634 ShouldNotReachHere(); | |
635 } | |
636 break; | |
637 } | |
638 | |
639 case lir_roundfp: { | |
640 assert(in->is_fpu_register() && !in->is_xmm_register(), "input must be in register"); | |
641 assert(res->is_stack(), "result must be on stack"); | |
642 | |
643 insert_exchange(in); | |
644 new_in = to_fpu_stack_top(in); | |
645 pop_if_last_use(op1, in); | |
646 break; | |
647 } | |
648 | |
649 default: { | |
650 assert(!in->is_float_kind() && !res->is_float_kind(), "missed a fpu-operation"); | |
651 } | |
652 } | |
653 | |
654 op1->set_in_opr(new_in); | |
655 op1->set_result_opr(new_res); | |
656 } | |
657 | |
658 void FpuStackAllocator::handle_op2(LIR_Op2* op2) { | |
659 LIR_Opr left = op2->in_opr1(); | |
660 if (!left->is_float_kind()) { | |
661 return; | |
662 } | |
663 if (left->is_xmm_register()) { | |
664 return; | |
665 } | |
666 | |
667 LIR_Opr right = op2->in_opr2(); | |
668 LIR_Opr res = op2->result_opr(); | |
669 LIR_Opr new_left = left; // new operands relative to the actual fpu stack top | |
670 LIR_Opr new_right = right; | |
671 LIR_Opr new_res = res; | |
672 | |
673 assert(!left->is_xmm_register() && !right->is_xmm_register() && !res->is_xmm_register(), "not for xmm registers"); | |
674 | |
675 switch (op2->code()) { | |
676 case lir_cmp: | |
677 case lir_cmp_fd2i: | |
678 case lir_ucmp_fd2i: { | |
679 assert(left->is_fpu_register(), "invalid LIR"); | |
680 assert(right->is_fpu_register(), "invalid LIR"); | |
681 | |
682 // the left-hand side must be on top of stack. | |
683 // the right-hand side is never popped, even if is_last_use is set | |
684 insert_exchange(left); | |
685 new_left = to_fpu_stack_top(left); | |
686 new_right = to_fpu_stack(right); | |
687 pop_if_last_use(op2, left); | |
688 break; | |
689 } | |
690 | |
691 case lir_mul_strictfp: | |
692 case lir_div_strictfp: { | |
693 assert(op2->tmp_opr()->is_fpu_register(), "strict operations need temporary fpu stack slot"); | |
694 insert_free_if_dead(op2->tmp_opr()); | |
695 assert(sim()->stack_size() <= 7, "at least one stack slot must be free"); | |
696 // fall-through: continue with the normal handling of lir_mul and lir_div | |
697 } | |
698 case lir_add: | |
699 case lir_sub: | |
700 case lir_mul: | |
701 case lir_div: { | |
702 assert(left->is_fpu_register(), "must be"); | |
703 assert(res->is_fpu_register(), "must be"); | |
704 assert(left->is_equal(res), "must be"); | |
705 | |
706 // either the left-hand or the right-hand side must be on top of stack | |
707 // (if right is not a register, left must be on top) | |
708 if (!right->is_fpu_register()) { | |
709 insert_exchange(left); | |
710 new_left = to_fpu_stack_top(left); | |
711 } else { | |
712 // no exchange necessary if right is alredy on top of stack | |
713 if (tos_offset(right) == 0) { | |
714 new_left = to_fpu_stack(left); | |
715 new_right = to_fpu_stack_top(right); | |
716 } else { | |
717 insert_exchange(left); | |
718 new_left = to_fpu_stack_top(left); | |
719 new_right = to_fpu_stack(right); | |
720 } | |
721 | |
722 if (right->is_last_use()) { | |
723 op2->set_fpu_pop_count(1); | |
724 | |
725 if (tos_offset(right) == 0) { | |
726 sim()->pop(); | |
727 } else { | |
728 // if left is on top of stack, the result is placed in the stack | |
729 // slot of right, so a renaming from right to res is necessary | |
730 assert(tos_offset(left) == 0, "must be"); | |
731 sim()->pop(); | |
732 do_rename(right, res); | |
733 } | |
734 } | |
735 } | |
736 new_res = to_fpu_stack(res); | |
737 | |
738 break; | |
739 } | |
740 | |
741 case lir_rem: { | |
742 assert(left->is_fpu_register(), "must be"); | |
743 assert(right->is_fpu_register(), "must be"); | |
744 assert(res->is_fpu_register(), "must be"); | |
745 assert(left->is_equal(res), "must be"); | |
746 | |
747 // Must bring both operands to top of stack with following operand ordering: | |
748 // * fpu stack before rem: ... right left | |
749 // * fpu stack after rem: ... left | |
750 if (tos_offset(right) != 1) { | |
751 insert_exchange(right); | |
752 insert_exchange(1); | |
753 } | |
754 insert_exchange(left); | |
755 assert(tos_offset(right) == 1, "check"); | |
756 assert(tos_offset(left) == 0, "check"); | |
757 | |
758 new_left = to_fpu_stack_top(left); | |
759 new_right = to_fpu_stack(right); | |
760 | |
761 op2->set_fpu_pop_count(1); | |
762 sim()->pop(); | |
763 do_rename(right, res); | |
764 | |
765 new_res = to_fpu_stack_top(res); | |
766 break; | |
767 } | |
768 | |
769 case lir_abs: | |
770 case lir_sqrt: { | |
771 // Right argument appears to be unused | |
772 assert(right->is_illegal(), "must be"); | |
773 assert(left->is_fpu_register(), "must be"); | |
774 assert(res->is_fpu_register(), "must be"); | |
775 assert(left->is_last_use(), "old value gets destroyed"); | |
776 | |
777 insert_free_if_dead(res, left); | |
778 insert_exchange(left); | |
779 do_rename(left, res); | |
780 | |
781 new_left = to_fpu_stack_top(res); | |
782 new_res = new_left; | |
783 | |
784 op2->set_fpu_stack_size(sim()->stack_size()); | |
785 break; | |
786 } | |
787 | |
953
ff1a29907b6c
6855215: Calculation error (NaN) after about 1500 calculations
never
parents:
0
diff
changeset
|
788 case lir_log: |
ff1a29907b6c
6855215: Calculation error (NaN) after about 1500 calculations
never
parents:
0
diff
changeset
|
789 case lir_log10: { |
ff1a29907b6c
6855215: Calculation error (NaN) after about 1500 calculations
never
parents:
0
diff
changeset
|
790 // log and log10 needs one temporary fpu stack slot, so there is ontemporary |
ff1a29907b6c
6855215: Calculation error (NaN) after about 1500 calculations
never
parents:
0
diff
changeset
|
791 // registers stored in temp of the operation. |
ff1a29907b6c
6855215: Calculation error (NaN) after about 1500 calculations
never
parents:
0
diff
changeset
|
792 // the stack allocator must guarantee that the stack slots are really free, |
ff1a29907b6c
6855215: Calculation error (NaN) after about 1500 calculations
never
parents:
0
diff
changeset
|
793 // otherwise there might be a stack overflow. |
ff1a29907b6c
6855215: Calculation error (NaN) after about 1500 calculations
never
parents:
0
diff
changeset
|
794 assert(right->is_illegal(), "must be"); |
ff1a29907b6c
6855215: Calculation error (NaN) after about 1500 calculations
never
parents:
0
diff
changeset
|
795 assert(left->is_fpu_register(), "must be"); |
ff1a29907b6c
6855215: Calculation error (NaN) after about 1500 calculations
never
parents:
0
diff
changeset
|
796 assert(res->is_fpu_register(), "must be"); |
ff1a29907b6c
6855215: Calculation error (NaN) after about 1500 calculations
never
parents:
0
diff
changeset
|
797 assert(op2->tmp_opr()->is_fpu_register(), "must be"); |
ff1a29907b6c
6855215: Calculation error (NaN) after about 1500 calculations
never
parents:
0
diff
changeset
|
798 |
ff1a29907b6c
6855215: Calculation error (NaN) after about 1500 calculations
never
parents:
0
diff
changeset
|
799 insert_free_if_dead(op2->tmp_opr()); |
ff1a29907b6c
6855215: Calculation error (NaN) after about 1500 calculations
never
parents:
0
diff
changeset
|
800 insert_free_if_dead(res, left); |
ff1a29907b6c
6855215: Calculation error (NaN) after about 1500 calculations
never
parents:
0
diff
changeset
|
801 insert_exchange(left); |
ff1a29907b6c
6855215: Calculation error (NaN) after about 1500 calculations
never
parents:
0
diff
changeset
|
802 do_rename(left, res); |
ff1a29907b6c
6855215: Calculation error (NaN) after about 1500 calculations
never
parents:
0
diff
changeset
|
803 |
ff1a29907b6c
6855215: Calculation error (NaN) after about 1500 calculations
never
parents:
0
diff
changeset
|
804 new_left = to_fpu_stack_top(res); |
ff1a29907b6c
6855215: Calculation error (NaN) after about 1500 calculations
never
parents:
0
diff
changeset
|
805 new_res = new_left; |
ff1a29907b6c
6855215: Calculation error (NaN) after about 1500 calculations
never
parents:
0
diff
changeset
|
806 |
ff1a29907b6c
6855215: Calculation error (NaN) after about 1500 calculations
never
parents:
0
diff
changeset
|
807 op2->set_fpu_stack_size(sim()->stack_size()); |
ff1a29907b6c
6855215: Calculation error (NaN) after about 1500 calculations
never
parents:
0
diff
changeset
|
808 assert(sim()->stack_size() <= 7, "at least one stack slot must be free"); |
ff1a29907b6c
6855215: Calculation error (NaN) after about 1500 calculations
never
parents:
0
diff
changeset
|
809 break; |
ff1a29907b6c
6855215: Calculation error (NaN) after about 1500 calculations
never
parents:
0
diff
changeset
|
810 } |
ff1a29907b6c
6855215: Calculation error (NaN) after about 1500 calculations
never
parents:
0
diff
changeset
|
811 |
0 | 812 |
813 case lir_tan: | |
814 case lir_sin: | |
815 case lir_cos: { | |
816 // sin and cos need two temporary fpu stack slots, so there are two temporary | |
817 // registers (stored in right and temp of the operation). | |
818 // the stack allocator must guarantee that the stack slots are really free, | |
819 // otherwise there might be a stack overflow. | |
820 assert(left->is_fpu_register(), "must be"); | |
821 assert(res->is_fpu_register(), "must be"); | |
822 // assert(left->is_last_use(), "old value gets destroyed"); | |
823 assert(right->is_fpu_register(), "right is used as the first temporary register"); | |
824 assert(op2->tmp_opr()->is_fpu_register(), "temp is used as the second temporary register"); | |
825 assert(fpu_num(left) != fpu_num(right) && fpu_num(right) != fpu_num(op2->tmp_opr()) && fpu_num(op2->tmp_opr()) != fpu_num(res), "need distinct temp registers"); | |
826 | |
827 insert_free_if_dead(right); | |
828 insert_free_if_dead(op2->tmp_opr()); | |
829 | |
830 insert_free_if_dead(res, left); | |
831 insert_exchange(left); | |
832 do_rename(left, res); | |
833 | |
834 new_left = to_fpu_stack_top(res); | |
835 new_res = new_left; | |
836 | |
837 op2->set_fpu_stack_size(sim()->stack_size()); | |
838 assert(sim()->stack_size() <= 6, "at least two stack slots must be free"); | |
839 break; | |
840 } | |
841 | |
842 default: { | |
843 assert(false, "missed a fpu-operation"); | |
844 } | |
845 } | |
846 | |
847 op2->set_in_opr1(new_left); | |
848 op2->set_in_opr2(new_right); | |
849 op2->set_result_opr(new_res); | |
850 } | |
851 | |
852 void FpuStackAllocator::handle_opCall(LIR_OpCall* opCall) { | |
853 LIR_Opr res = opCall->result_opr(); | |
854 | |
855 // clear fpu-stack before call | |
856 // it may contain dead values that could not have been remved by previous operations | |
857 clear_fpu_stack(LIR_OprFact::illegalOpr); | |
858 assert(sim()->is_empty(), "fpu stack must be empty now"); | |
859 | |
860 // compute debug information before (possible) fpu result is pushed | |
861 compute_debug_information(opCall); | |
862 | |
863 if (res->is_fpu_register() && !res->is_xmm_register()) { | |
864 do_push(res); | |
865 opCall->set_result_opr(to_fpu_stack_top(res)); | |
866 } | |
867 } | |
868 | |
869 #ifndef PRODUCT | |
870 void FpuStackAllocator::check_invalid_lir_op(LIR_Op* op) { | |
871 switch (op->code()) { | |
872 case lir_24bit_FPU: | |
873 case lir_reset_FPU: | |
874 case lir_ffree: | |
875 assert(false, "operations not allowed in lir. If one of these operations is needed, check if they have fpu operands"); | |
876 break; | |
877 | |
878 case lir_fpop_raw: | |
879 case lir_fxch: | |
880 case lir_fld: | |
881 assert(false, "operations only inserted by FpuStackAllocator"); | |
882 break; | |
883 } | |
884 } | |
885 #endif | |
886 | |
887 | |
888 void FpuStackAllocator::merge_insert_add(LIR_List* instrs, FpuStackSim* cur_sim, int reg) { | |
889 LIR_Op1* move = new LIR_Op1(lir_move, LIR_OprFact::doubleConst(0), LIR_OprFact::double_fpu(reg)->make_fpu_stack_offset()); | |
890 | |
891 instrs->instructions_list()->push(move); | |
892 | |
893 cur_sim->push(reg); | |
894 move->set_result_opr(to_fpu_stack(move->result_opr())); | |
895 | |
896 #ifndef PRODUCT | |
897 if (TraceFPUStack) { | |
898 tty->print("Added new register: %d New state: ", reg); cur_sim->print(); tty->cr(); | |
899 } | |
900 #endif | |
901 } | |
902 | |
903 void FpuStackAllocator::merge_insert_xchg(LIR_List* instrs, FpuStackSim* cur_sim, int slot) { | |
904 assert(slot > 0, "no exchange necessary"); | |
905 | |
906 LIR_Op1* fxch = new LIR_Op1(lir_fxch, LIR_OprFact::intConst(slot)); | |
907 instrs->instructions_list()->push(fxch); | |
908 cur_sim->swap(slot); | |
909 | |
910 #ifndef PRODUCT | |
911 if (TraceFPUStack) { | |
912 tty->print("Exchanged register: %d New state: ", cur_sim->get_slot(slot)); cur_sim->print(); tty->cr(); | |
913 } | |
914 #endif | |
915 } | |
916 | |
917 void FpuStackAllocator::merge_insert_pop(LIR_List* instrs, FpuStackSim* cur_sim) { | |
918 int reg = cur_sim->get_slot(0); | |
919 | |
920 LIR_Op* fpop = new LIR_Op0(lir_fpop_raw); | |
921 instrs->instructions_list()->push(fpop); | |
922 cur_sim->pop(reg); | |
923 | |
924 #ifndef PRODUCT | |
925 if (TraceFPUStack) { | |
926 tty->print("Removed register: %d New state: ", reg); cur_sim->print(); tty->cr(); | |
927 } | |
928 #endif | |
929 } | |
930 | |
931 bool FpuStackAllocator::merge_rename(FpuStackSim* cur_sim, FpuStackSim* sux_sim, int start_slot, int change_slot) { | |
932 int reg = cur_sim->get_slot(change_slot); | |
933 | |
934 for (int slot = start_slot; slot >= 0; slot--) { | |
935 int new_reg = sux_sim->get_slot(slot); | |
936 | |
937 if (!cur_sim->contains(new_reg)) { | |
938 cur_sim->set_slot(change_slot, new_reg); | |
939 | |
940 #ifndef PRODUCT | |
941 if (TraceFPUStack) { | |
942 tty->print("Renamed register %d to %d New state: ", reg, new_reg); cur_sim->print(); tty->cr(); | |
943 } | |
944 #endif | |
945 | |
946 return true; | |
947 } | |
948 } | |
949 return false; | |
950 } | |
951 | |
952 | |
953 void FpuStackAllocator::merge_fpu_stack(LIR_List* instrs, FpuStackSim* cur_sim, FpuStackSim* sux_sim) { | |
954 #ifndef PRODUCT | |
955 if (TraceFPUStack) { | |
956 tty->cr(); | |
957 tty->print("before merging: pred: "); cur_sim->print(); tty->cr(); | |
958 tty->print(" sux: "); sux_sim->print(); tty->cr(); | |
959 } | |
960 | |
961 int slot; | |
962 for (slot = 0; slot < cur_sim->stack_size(); slot++) { | |
963 assert(!cur_sim->slot_is_empty(slot), "not handled by algorithm"); | |
964 } | |
965 for (slot = 0; slot < sux_sim->stack_size(); slot++) { | |
966 assert(!sux_sim->slot_is_empty(slot), "not handled by algorithm"); | |
967 } | |
968 #endif | |
969 | |
970 // size difference between cur and sux that must be resolved by adding or removing values form the stack | |
971 int size_diff = cur_sim->stack_size() - sux_sim->stack_size(); | |
972 | |
973 if (!ComputeExactFPURegisterUsage) { | |
974 // add slots that are currently free, but used in successor | |
975 // When the exact FPU register usage is computed, the stack does | |
976 // not contain dead values at merging -> no values must be added | |
977 | |
978 int sux_slot = sux_sim->stack_size() - 1; | |
979 while (size_diff < 0) { | |
980 assert(sux_slot >= 0, "slot out of bounds -> error in algorithm"); | |
981 | |
982 int reg = sux_sim->get_slot(sux_slot); | |
983 if (!cur_sim->contains(reg)) { | |
984 merge_insert_add(instrs, cur_sim, reg); | |
985 size_diff++; | |
986 | |
987 if (sux_slot + size_diff != 0) { | |
988 merge_insert_xchg(instrs, cur_sim, sux_slot + size_diff); | |
989 } | |
990 } | |
991 sux_slot--; | |
992 } | |
993 } | |
994 | |
995 assert(cur_sim->stack_size() >= sux_sim->stack_size(), "stack size must be equal or greater now"); | |
996 assert(size_diff == cur_sim->stack_size() - sux_sim->stack_size(), "must be"); | |
997 | |
998 // stack merge algorithm: | |
999 // 1) as long as the current stack top is not in the right location (that meens | |
1000 // it should not be on the stack top), exchange it into the right location | |
1001 // 2) if the stack top is right, but the remaining stack is not ordered correctly, | |
1002 // the stack top is exchanged away to get another value on top -> | |
1003 // now step 1) can be continued | |
1004 // the stack can also contain unused items -> these items are removed from stack | |
1005 | |
1006 int finished_slot = sux_sim->stack_size() - 1; | |
1007 while (finished_slot >= 0 || size_diff > 0) { | |
1008 while (size_diff > 0 || (cur_sim->stack_size() > 0 && cur_sim->get_slot(0) != sux_sim->get_slot(0))) { | |
1009 int reg = cur_sim->get_slot(0); | |
1010 if (sux_sim->contains(reg)) { | |
1011 int sux_slot = sux_sim->offset_from_tos(reg); | |
1012 merge_insert_xchg(instrs, cur_sim, sux_slot + size_diff); | |
1013 | |
1014 } else if (!merge_rename(cur_sim, sux_sim, finished_slot, 0)) { | |
1015 assert(size_diff > 0, "must be"); | |
1016 | |
1017 merge_insert_pop(instrs, cur_sim); | |
1018 size_diff--; | |
1019 } | |
1020 assert(cur_sim->stack_size() == 0 || cur_sim->get_slot(0) != reg, "register must have been changed"); | |
1021 } | |
1022 | |
1023 while (finished_slot >= 0 && cur_sim->get_slot(finished_slot) == sux_sim->get_slot(finished_slot)) { | |
1024 finished_slot--; | |
1025 } | |
1026 | |
1027 if (finished_slot >= 0) { | |
1028 int reg = cur_sim->get_slot(finished_slot); | |
1029 | |
1030 if (sux_sim->contains(reg) || !merge_rename(cur_sim, sux_sim, finished_slot, finished_slot)) { | |
1031 assert(sux_sim->contains(reg) || size_diff > 0, "must be"); | |
1032 merge_insert_xchg(instrs, cur_sim, finished_slot); | |
1033 } | |
1034 assert(cur_sim->get_slot(finished_slot) != reg, "register must have been changed"); | |
1035 } | |
1036 } | |
1037 | |
1038 #ifndef PRODUCT | |
1039 if (TraceFPUStack) { | |
1040 tty->print("after merging: pred: "); cur_sim->print(); tty->cr(); | |
1041 tty->print(" sux: "); sux_sim->print(); tty->cr(); | |
1042 tty->cr(); | |
1043 } | |
1044 #endif | |
1045 assert(cur_sim->stack_size() == sux_sim->stack_size(), "stack size must be equal now"); | |
1046 } | |
1047 | |
1048 | |
1049 void FpuStackAllocator::merge_cleanup_fpu_stack(LIR_List* instrs, FpuStackSim* cur_sim, BitMap& live_fpu_regs) { | |
1050 #ifndef PRODUCT | |
1051 if (TraceFPUStack) { | |
1052 tty->cr(); | |
1053 tty->print("before cleanup: state: "); cur_sim->print(); tty->cr(); | |
1054 tty->print(" live: "); live_fpu_regs.print_on(tty); tty->cr(); | |
1055 } | |
1056 #endif | |
1057 | |
1058 int slot = 0; | |
1059 while (slot < cur_sim->stack_size()) { | |
1060 int reg = cur_sim->get_slot(slot); | |
1061 if (!live_fpu_regs.at(reg)) { | |
1062 if (slot != 0) { | |
1063 merge_insert_xchg(instrs, cur_sim, slot); | |
1064 } | |
1065 merge_insert_pop(instrs, cur_sim); | |
1066 } else { | |
1067 slot++; | |
1068 } | |
1069 } | |
1070 | |
1071 #ifndef PRODUCT | |
1072 if (TraceFPUStack) { | |
1073 tty->print("after cleanup: state: "); cur_sim->print(); tty->cr(); | |
1074 tty->print(" live: "); live_fpu_regs.print_on(tty); tty->cr(); | |
1075 tty->cr(); | |
1076 } | |
1077 | |
1078 // check if fpu stack only contains live registers | |
1079 for (unsigned int i = 0; i < live_fpu_regs.size(); i++) { | |
1080 if (live_fpu_regs.at(i) != cur_sim->contains(i)) { | |
1081 tty->print_cr("mismatch between required and actual stack content"); | |
1082 break; | |
1083 } | |
1084 } | |
1085 #endif | |
1086 } | |
1087 | |
1088 | |
1089 bool FpuStackAllocator::merge_fpu_stack_with_successors(BlockBegin* block) { | |
1090 #ifndef PRODUCT | |
1091 if (TraceFPUStack) { | |
1092 tty->print_cr("Propagating FPU stack state for B%d at LIR_Op position %d to successors:", | |
1093 block->block_id(), pos()); | |
1094 sim()->print(); | |
1095 tty->cr(); | |
1096 } | |
1097 #endif | |
1098 | |
1099 bool changed = false; | |
1100 int number_of_sux = block->number_of_sux(); | |
1101 | |
1102 if (number_of_sux == 1 && block->sux_at(0)->number_of_preds() > 1) { | |
1103 // The successor has at least two incoming edges, so a stack merge will be necessary | |
1104 // If this block is the first predecessor, cleanup the current stack and propagate it | |
1105 // If this block is not the first predecessor, a stack merge will be necessary | |
1106 | |
1107 BlockBegin* sux = block->sux_at(0); | |
1108 intArray* state = sux->fpu_stack_state(); | |
1109 LIR_List* instrs = new LIR_List(_compilation); | |
1110 | |
1111 if (state != NULL) { | |
1112 // Merge with a successors that already has a FPU stack state | |
1113 // the block must only have one successor because critical edges must been split | |
1114 FpuStackSim* cur_sim = sim(); | |
1115 FpuStackSim* sux_sim = temp_sim(); | |
1116 sux_sim->read_state(state); | |
1117 | |
1118 merge_fpu_stack(instrs, cur_sim, sux_sim); | |
1119 | |
1120 } else { | |
1121 // propagate current FPU stack state to successor without state | |
1122 // clean up stack first so that there are no dead values on the stack | |
1123 if (ComputeExactFPURegisterUsage) { | |
1124 FpuStackSim* cur_sim = sim(); | |
1125 BitMap live_fpu_regs = block->sux_at(0)->fpu_register_usage(); | |
1126 assert(live_fpu_regs.size() == FrameMap::nof_fpu_regs, "missing register usage"); | |
1127 | |
1128 merge_cleanup_fpu_stack(instrs, cur_sim, live_fpu_regs); | |
1129 } | |
1130 | |
1131 intArray* state = sim()->write_state(); | |
1132 if (TraceFPUStack) { | |
1133 tty->print_cr("Setting FPU stack state of B%d (merge path)", sux->block_id()); | |
1134 sim()->print(); tty->cr(); | |
1135 } | |
1136 sux->set_fpu_stack_state(state); | |
1137 } | |
1138 | |
1139 if (instrs->instructions_list()->length() > 0) { | |
1140 lir()->insert_before(pos(), instrs); | |
1141 set_pos(instrs->instructions_list()->length() + pos()); | |
1142 changed = true; | |
1143 } | |
1144 | |
1145 } else { | |
1146 // Propagate unmodified Stack to successors where a stack merge is not necessary | |
1147 intArray* state = sim()->write_state(); | |
1148 for (int i = 0; i < number_of_sux; i++) { | |
1149 BlockBegin* sux = block->sux_at(i); | |
1150 | |
1151 #ifdef ASSERT | |
1152 for (int j = 0; j < sux->number_of_preds(); j++) { | |
1153 assert(block == sux->pred_at(j), "all critical edges must be broken"); | |
1154 } | |
1155 | |
1156 // check if new state is same | |
1157 if (sux->fpu_stack_state() != NULL) { | |
1158 intArray* sux_state = sux->fpu_stack_state(); | |
1159 assert(state->length() == sux_state->length(), "overwriting existing stack state"); | |
1160 for (int j = 0; j < state->length(); j++) { | |
1161 assert(state->at(j) == sux_state->at(j), "overwriting existing stack state"); | |
1162 } | |
1163 } | |
1164 #endif | |
1165 #ifndef PRODUCT | |
1166 if (TraceFPUStack) { | |
1167 tty->print_cr("Setting FPU stack state of B%d", sux->block_id()); | |
1168 sim()->print(); tty->cr(); | |
1169 } | |
1170 #endif | |
1171 | |
1172 sux->set_fpu_stack_state(state); | |
1173 } | |
1174 } | |
1175 | |
1176 #ifndef PRODUCT | |
1177 // assertions that FPU stack state conforms to all successors' states | |
1178 intArray* cur_state = sim()->write_state(); | |
1179 for (int i = 0; i < number_of_sux; i++) { | |
1180 BlockBegin* sux = block->sux_at(i); | |
1181 intArray* sux_state = sux->fpu_stack_state(); | |
1182 | |
1183 assert(sux_state != NULL, "no fpu state"); | |
1184 assert(cur_state->length() == sux_state->length(), "incorrect length"); | |
1185 for (int i = 0; i < cur_state->length(); i++) { | |
1186 assert(cur_state->at(i) == sux_state->at(i), "element not equal"); | |
1187 } | |
1188 } | |
1189 #endif | |
1190 | |
1191 return changed; | |
1192 } |