1 /*
2 * Copyright (c) 2018, 2025, 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.
18 *
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.
22 *
23 */
24
25 #include "precompiled.hpp"
26 #include "asm/macroAssembler.inline.hpp"
27 #include "classfile/classLoaderData.hpp"
28 #include "gc/shared/barrierSet.hpp"
29 #include "gc/shared/barrierSetAssembler.hpp"
30 #include "gc/shared/barrierSetNMethod.hpp"
31 #include "gc/shared/barrierSetRuntime.hpp"
32 #include "gc/shared/collectedHeap.hpp"
33 #include "interpreter/interp_masm.hpp"
34 #include "memory/universe.hpp"
35 #include "runtime/javaThread.hpp"
36 #include "runtime/jniHandles.hpp"
37 #include "runtime/sharedRuntime.hpp"
38 #include "runtime/stubRoutines.hpp"
39 #ifdef COMPILER2
40 #include "gc/shared/c2/barrierSetC2.hpp"
41 #endif // COMPILER2
42
43 #define __ masm->
44
45 void BarrierSetAssembler::load_at(MacroAssembler* masm, DecoratorSet decorators, BasicType type,
46 Register dst, Address src, Register tmp1, Register tmp_thread) {
47 bool in_heap = (decorators & IN_HEAP) != 0;
48 bool in_native = (decorators & IN_NATIVE) != 0;
49 bool is_not_null = (decorators & IS_NOT_NULL) != 0;
50 bool atomic = (decorators & MO_RELAXED) != 0;
51
52 switch (type) {
53 case T_OBJECT:
54 case T_ARRAY: {
55 if (in_heap) {
56 #ifdef _LP64
57 if (UseCompressedOops) {
58 __ movl(dst, src);
59 if (is_not_null) {
60 __ decode_heap_oop_not_null(dst);
61 } else {
62 __ decode_heap_oop(dst);
63 }
64 } else
65 #endif
66 {
67 __ movptr(dst, src);
68 }
69 } else {
70 assert(in_native, "why else?");
71 __ movptr(dst, src);
72 }
73 break;
74 }
75 case T_BOOLEAN: __ load_unsigned_byte(dst, src); break;
76 case T_BYTE: __ load_signed_byte(dst, src); break;
77 case T_CHAR: __ load_unsigned_short(dst, src); break;
78 case T_SHORT: __ load_signed_short(dst, src); break;
79 case T_INT: __ movl (dst, src); break;
80 case T_ADDRESS: __ movptr(dst, src); break;
81 case T_FLOAT:
82 assert(dst == noreg, "only to ftos");
83 __ load_float(src);
84 break;
85 case T_DOUBLE:
86 assert(dst == noreg, "only to dtos");
87 __ load_double(src);
88 break;
89 case T_LONG:
90 assert(dst == noreg, "only to ltos");
91 #ifdef _LP64
92 __ movq(rax, src);
93 #else
94 if (atomic) {
95 __ fild_d(src); // Must load atomically
96 __ subptr(rsp,2*wordSize); // Make space for store
97 __ fistp_d(Address(rsp,0));
98 __ pop(rax);
99 __ pop(rdx);
100 } else {
101 __ movl(rax, src);
102 __ movl(rdx, src.plus_disp(wordSize));
103 }
104 #endif
105 break;
106 default: Unimplemented();
107 }
108 }
109
110 void BarrierSetAssembler::store_at(MacroAssembler* masm, DecoratorSet decorators, BasicType type,
111 Address dst, Register val, Register tmp1, Register tmp2, Register tmp3) {
112 bool in_heap = (decorators & IN_HEAP) != 0;
113 bool in_native = (decorators & IN_NATIVE) != 0;
114 bool is_not_null = (decorators & IS_NOT_NULL) != 0;
115 bool atomic = (decorators & MO_RELAXED) != 0;
116
117 switch (type) {
118 case T_OBJECT:
119 case T_ARRAY: {
120 if (in_heap) {
121 if (val == noreg) {
122 assert(!is_not_null, "inconsistent access");
123 #ifdef _LP64
124 if (UseCompressedOops) {
125 __ movl(dst, NULL_WORD);
126 } else {
127 __ movslq(dst, NULL_WORD);
128 }
129 #else
130 __ movl(dst, NULL_WORD);
131 #endif
132 } else {
133 #ifdef _LP64
134 if (UseCompressedOops) {
135 assert(!dst.uses(val), "not enough registers");
136 if (is_not_null) {
137 __ encode_heap_oop_not_null(val);
138 } else {
139 __ encode_heap_oop(val);
140 }
141 __ movl(dst, val);
142 } else
143 #endif
144 {
145 __ movptr(dst, val);
146 }
147 }
148 } else {
149 assert(in_native, "why else?");
150 assert(val != noreg, "not supported");
151 __ movptr(dst, val);
152 }
153 break;
154 }
155 case T_BOOLEAN:
156 __ andl(val, 0x1); // boolean is true if LSB is 1
157 __ movb(dst, val);
158 break;
159 case T_BYTE:
160 __ movb(dst, val);
161 break;
162 case T_SHORT:
163 __ movw(dst, val);
164 break;
165 case T_CHAR:
166 __ movw(dst, val);
167 break;
168 case T_INT:
169 __ movl(dst, val);
170 break;
171 case T_LONG:
172 assert(val == noreg, "only tos");
173 #ifdef _LP64
174 __ movq(dst, rax);
175 #else
176 if (atomic) {
177 __ push(rdx);
178 __ push(rax); // Must update atomically with FIST
179 __ fild_d(Address(rsp,0)); // So load into FPU register
180 __ fistp_d(dst); // and put into memory atomically
181 __ addptr(rsp, 2*wordSize);
182 } else {
183 __ movptr(dst, rax);
184 __ movptr(dst.plus_disp(wordSize), rdx);
185 }
186 #endif
187 break;
188 case T_FLOAT:
189 assert(val == noreg, "only tos");
190 __ store_float(dst);
191 break;
192 case T_DOUBLE:
193 assert(val == noreg, "only tos");
194 __ store_double(dst);
195 break;
196 case T_ADDRESS:
197 __ movptr(dst, val);
198 break;
199 default: Unimplemented();
200 }
201 }
202
203 void BarrierSetAssembler::flat_field_copy(MacroAssembler* masm, DecoratorSet decorators,
204 Register src, Register dst, Register inline_layout_info) {
205 // flat_field_copy implementation is fairly complex, and there are not any
206 // "short-cuts" to be made from asm. What there is, appears to have the same
207 // cost in C++, so just "call_VM_leaf" for now rather than maintain hundreds
208 // of hand-rolled instructions...
209 if (decorators & IS_DEST_UNINITIALIZED) {
210 __ call_VM_leaf(CAST_FROM_FN_PTR(address, BarrierSetRuntime::value_copy_is_dest_uninitialized), src, dst, inline_layout_info);
211 } else {
212 __ call_VM_leaf(CAST_FROM_FN_PTR(address, BarrierSetRuntime::value_copy), src, dst, inline_layout_info);
213 }
214 }
215
216 void BarrierSetAssembler::copy_load_at(MacroAssembler* masm,
217 DecoratorSet decorators,
218 BasicType type,
219 size_t bytes,
220 Register dst,
221 Address src,
222 Register tmp) {
223 assert(bytes <= 8, "can only deal with non-vector registers");
224 switch (bytes) {
225 case 1:
226 __ movb(dst, src);
227 break;
228 case 2:
229 __ movw(dst, src);
230 break;
231 case 4:
232 __ movl(dst, src);
233 break;
234 case 8:
235 #ifdef _LP64
236 __ movq(dst, src);
237 #else
238 fatal("No support for 8 bytes copy");
239 #endif
240 break;
241 default:
242 fatal("Unexpected size");
243 }
244 #ifdef _LP64
245 if ((decorators & ARRAYCOPY_CHECKCAST) != 0 && UseCompressedOops) {
246 __ decode_heap_oop(dst);
247 }
248 #endif
249 }
250
251 void BarrierSetAssembler::copy_store_at(MacroAssembler* masm,
252 DecoratorSet decorators,
253 BasicType type,
254 size_t bytes,
255 Address dst,
256 Register src,
257 Register tmp) {
258 #ifdef _LP64
259 if ((decorators & ARRAYCOPY_CHECKCAST) != 0 && UseCompressedOops) {
260 __ encode_heap_oop(src);
261 }
262 #endif
263 assert(bytes <= 8, "can only deal with non-vector registers");
264 switch (bytes) {
265 case 1:
266 __ movb(dst, src);
267 break;
268 case 2:
269 __ movw(dst, src);
270 break;
271 case 4:
272 __ movl(dst, src);
273 break;
274 case 8:
275 #ifdef _LP64
276 __ movq(dst, src);
277 #else
278 fatal("No support for 8 bytes copy");
279 #endif
280 break;
281 default:
282 fatal("Unexpected size");
283 }
284 }
285
286 void BarrierSetAssembler::copy_load_at(MacroAssembler* masm,
287 DecoratorSet decorators,
288 BasicType type,
289 size_t bytes,
290 XMMRegister dst,
291 Address src,
292 Register tmp,
293 XMMRegister xmm_tmp) {
294 assert(bytes > 8, "can only deal with vector registers");
295 if (bytes == 16) {
296 __ movdqu(dst, src);
297 } else if (bytes == 32) {
298 __ vmovdqu(dst, src);
299 } else {
300 fatal("No support for >32 bytes copy");
301 }
302 }
303
304 void BarrierSetAssembler::copy_store_at(MacroAssembler* masm,
305 DecoratorSet decorators,
306 BasicType type,
307 size_t bytes,
308 Address dst,
309 XMMRegister src,
310 Register tmp1,
311 Register tmp2,
312 XMMRegister xmm_tmp) {
313 assert(bytes > 8, "can only deal with vector registers");
314 if (bytes == 16) {
315 __ movdqu(dst, src);
316 } else if (bytes == 32) {
317 __ vmovdqu(dst, src);
318 } else {
319 fatal("No support for >32 bytes copy");
320 }
321 }
322
323 void BarrierSetAssembler::try_resolve_jobject_in_native(MacroAssembler* masm, Register jni_env,
324 Register obj, Register tmp, Label& slowpath) {
325 __ clear_jobject_tag(obj);
326 __ movptr(obj, Address(obj, 0));
327 }
328
329 void BarrierSetAssembler::tlab_allocate(MacroAssembler* masm,
330 Register thread, Register obj,
331 Register var_size_in_bytes,
332 int con_size_in_bytes,
333 Register t1,
334 Register t2,
335 Label& slow_case) {
336 assert_different_registers(obj, t1, t2);
337 assert_different_registers(obj, var_size_in_bytes, t1);
338 Register end = t2;
339 if (!thread->is_valid()) {
340 #ifdef _LP64
341 thread = r15_thread;
342 #else
343 assert(t1->is_valid(), "need temp reg");
344 thread = t1;
345 __ get_thread(thread);
346 #endif
347 }
348
349 __ verify_tlab();
350
351 __ movptr(obj, Address(thread, JavaThread::tlab_top_offset()));
352 if (var_size_in_bytes == noreg) {
353 __ lea(end, Address(obj, con_size_in_bytes));
354 } else {
355 __ lea(end, Address(obj, var_size_in_bytes, Address::times_1));
356 }
357 __ cmpptr(end, Address(thread, JavaThread::tlab_end_offset()));
358 __ jcc(Assembler::above, slow_case);
359
360 // update the tlab top pointer
361 __ movptr(Address(thread, JavaThread::tlab_top_offset()), end);
362
363 // recover var_size_in_bytes if necessary
364 if (var_size_in_bytes == end) {
365 __ subptr(var_size_in_bytes, obj);
366 }
367 __ verify_tlab();
368 }
369
370 #ifdef _LP64
371 void BarrierSetAssembler::nmethod_entry_barrier(MacroAssembler* masm, Label* slow_path, Label* continuation) {
372 BarrierSetNMethod* bs_nm = BarrierSet::barrier_set()->barrier_set_nmethod();
373 if (bs_nm == nullptr) {
374 return;
375 }
376 Register thread = r15_thread;
377 Address disarmed_addr(thread, in_bytes(bs_nm->thread_disarmed_guard_value_offset()));
378 // The immediate is the last 4 bytes, so if we align the start of the cmp
379 // instruction to 4 bytes, we know that the second half of it is also 4
380 // byte aligned, which means that the immediate will not cross a cache line
381 __ align(4);
382 uintptr_t before_cmp = (uintptr_t)__ pc();
383 __ cmpl_imm32(disarmed_addr, 0);
384 uintptr_t after_cmp = (uintptr_t)__ pc();
385 guarantee(after_cmp - before_cmp == 8, "Wrong assumed instruction length");
386
387 if (slow_path != nullptr) {
388 __ jcc(Assembler::notEqual, *slow_path);
389 __ bind(*continuation);
390 } else {
391 Label done;
392 __ jccb(Assembler::equal, done);
393 __ call(RuntimeAddress(StubRoutines::method_entry_barrier()));
394 __ bind(done);
395 }
396 }
397 #else
398 void BarrierSetAssembler::nmethod_entry_barrier(MacroAssembler* masm, Label*, Label*) {
399 BarrierSetNMethod* bs_nm = BarrierSet::barrier_set()->barrier_set_nmethod();
400 if (bs_nm == nullptr) {
401 return;
402 }
403
404 Label continuation;
405
406 Register tmp = rdi;
407 __ push(tmp);
408 __ movptr(tmp, (intptr_t)bs_nm->disarmed_guard_value_address());
409 Address disarmed_addr(tmp, 0);
410 __ align(4);
411 __ cmpl_imm32(disarmed_addr, 0);
412 __ pop(tmp);
413 __ jcc(Assembler::equal, continuation);
414 __ call(RuntimeAddress(StubRoutines::method_entry_barrier()));
415 __ bind(continuation);
416 }
417 #endif
418
419 void BarrierSetAssembler::c2i_entry_barrier(MacroAssembler* masm) {
420 BarrierSetNMethod* bs = BarrierSet::barrier_set()->barrier_set_nmethod();
421 if (bs == nullptr) {
422 return;
423 }
424
425 Label bad_call;
426 __ cmpptr(rbx, 0); // rbx contains the incoming method for c2i adapters.
427 __ jcc(Assembler::equal, bad_call);
428
429 Register tmp1 = LP64_ONLY( rscratch1 ) NOT_LP64( rax );
430 Register tmp2 = LP64_ONLY( rscratch2 ) NOT_LP64( rcx );
431 #ifndef _LP64
432 __ push(tmp1);
433 __ push(tmp2);
434 #endif // !_LP64
435
436 // Pointer chase to the method holder to find out if the method is concurrently unloading.
437 Label method_live;
438 __ load_method_holder_cld(tmp1, rbx);
439
440 // Is it a strong CLD?
441 __ cmpl(Address(tmp1, ClassLoaderData::keep_alive_ref_count_offset()), 0);
442 __ jcc(Assembler::greater, method_live);
443
444 // Is it a weak but alive CLD?
445 __ movptr(tmp1, Address(tmp1, ClassLoaderData::holder_offset()));
446 __ resolve_weak_handle(tmp1, tmp2);
447 __ cmpptr(tmp1, 0);
448 __ jcc(Assembler::notEqual, method_live);
449
450 #ifndef _LP64
451 __ pop(tmp2);
452 __ pop(tmp1);
453 #endif
454
455 __ bind(bad_call);
456 __ jump(RuntimeAddress(SharedRuntime::get_handle_wrong_method_stub()));
457 __ bind(method_live);
458
459 #ifndef _LP64
460 __ pop(tmp2);
461 __ pop(tmp1);
462 #endif
463 }
464
465 void BarrierSetAssembler::check_oop(MacroAssembler* masm, Register obj, Register tmp1, Register tmp2, Label& error) {
466 // Check if the oop is in the right area of memory
467 __ movptr(tmp1, obj);
468 __ movptr(tmp2, (intptr_t) Universe::verify_oop_mask());
469 __ andptr(tmp1, tmp2);
470 __ movptr(tmp2, (intptr_t) Universe::verify_oop_bits());
471 __ cmpptr(tmp1, tmp2);
472 __ jcc(Assembler::notZero, error);
473
474 // make sure klass is 'reasonable', which is not zero.
475 __ load_klass(obj, obj, tmp1); // get klass
476 __ testptr(obj, obj);
477 __ jcc(Assembler::zero, error); // if klass is null it is broken
478 }
479
480 #ifdef COMPILER2
481
482 #ifdef _LP64
483
484 OptoReg::Name BarrierSetAssembler::refine_register(const Node* node, OptoReg::Name opto_reg) {
485 if (!OptoReg::is_reg(opto_reg)) {
486 return OptoReg::Bad;
487 }
488
489 const VMReg vm_reg = OptoReg::as_VMReg(opto_reg);
490 if (vm_reg->is_XMMRegister()) {
491 opto_reg &= ~15;
492 switch (node->ideal_reg()) {
493 case Op_VecX:
494 opto_reg |= 2;
495 break;
496 case Op_VecY:
497 opto_reg |= 4;
498 break;
499 case Op_VecZ:
500 opto_reg |= 8;
501 break;
502 default:
503 opto_reg |= 1;
504 break;
505 }
506 }
507
508 return opto_reg;
509 }
510
511 // We use the vec_spill_helper from the x86.ad file to avoid reinventing this wheel
512 extern void vec_spill_helper(C2_MacroAssembler *masm, bool is_load,
513 int stack_offset, int reg, uint ireg, outputStream* st);
514
515 #undef __
516 #define __ _masm->
517
518 int SaveLiveRegisters::xmm_compare_register_size(XMMRegisterData* left, XMMRegisterData* right) {
519 if (left->_size == right->_size) {
520 return 0;
521 }
522
523 return (left->_size < right->_size) ? -1 : 1;
524 }
525
526 int SaveLiveRegisters::xmm_slot_size(OptoReg::Name opto_reg) {
527 // The low order 4 bytes denote what size of the XMM register is live
528 return (opto_reg & 15) << 3;
529 }
530
531 uint SaveLiveRegisters::xmm_ideal_reg_for_size(int reg_size) {
532 switch (reg_size) {
533 case 8:
534 return Op_VecD;
535 case 16:
536 return Op_VecX;
537 case 32:
538 return Op_VecY;
539 case 64:
540 return Op_VecZ;
541 default:
542 fatal("Invalid register size %d", reg_size);
543 return 0;
544 }
545 }
546
547 bool SaveLiveRegisters::xmm_needs_vzeroupper() const {
548 return _xmm_registers.is_nonempty() && _xmm_registers.at(0)._size > 16;
549 }
550
551 void SaveLiveRegisters::xmm_register_save(const XMMRegisterData& reg_data) {
552 const OptoReg::Name opto_reg = OptoReg::as_OptoReg(reg_data._reg->as_VMReg());
553 const uint ideal_reg = xmm_ideal_reg_for_size(reg_data._size);
554 _spill_offset -= reg_data._size;
555 C2_MacroAssembler c2_masm(__ code());
556 vec_spill_helper(&c2_masm, false /* is_load */, _spill_offset, opto_reg, ideal_reg, tty);
557 }
558
559 void SaveLiveRegisters::xmm_register_restore(const XMMRegisterData& reg_data) {
560 const OptoReg::Name opto_reg = OptoReg::as_OptoReg(reg_data._reg->as_VMReg());
561 const uint ideal_reg = xmm_ideal_reg_for_size(reg_data._size);
562 C2_MacroAssembler c2_masm(__ code());
563 vec_spill_helper(&c2_masm, true /* is_load */, _spill_offset, opto_reg, ideal_reg, tty);
564 _spill_offset += reg_data._size;
565 }
566
567 void SaveLiveRegisters::gp_register_save(Register reg) {
568 _spill_offset -= 8;
569 __ movq(Address(rsp, _spill_offset), reg);
570 }
571
572 void SaveLiveRegisters::opmask_register_save(KRegister reg) {
573 _spill_offset -= 8;
574 __ kmov(Address(rsp, _spill_offset), reg);
575 }
576
577 void SaveLiveRegisters::gp_register_restore(Register reg) {
578 __ movq(reg, Address(rsp, _spill_offset));
579 _spill_offset += 8;
580 }
581
582 void SaveLiveRegisters::opmask_register_restore(KRegister reg) {
583 __ kmov(reg, Address(rsp, _spill_offset));
584 _spill_offset += 8;
585 }
586
587 void SaveLiveRegisters::initialize(BarrierStubC2* stub) {
588 // Create mask of caller saved registers that need to
589 // be saved/restored if live
590 RegMask caller_saved;
591 caller_saved.Insert(OptoReg::as_OptoReg(rax->as_VMReg()));
592 caller_saved.Insert(OptoReg::as_OptoReg(rcx->as_VMReg()));
593 caller_saved.Insert(OptoReg::as_OptoReg(rdx->as_VMReg()));
594 caller_saved.Insert(OptoReg::as_OptoReg(rsi->as_VMReg()));
595 caller_saved.Insert(OptoReg::as_OptoReg(rdi->as_VMReg()));
596 caller_saved.Insert(OptoReg::as_OptoReg(r8->as_VMReg()));
597 caller_saved.Insert(OptoReg::as_OptoReg(r9->as_VMReg()));
598 caller_saved.Insert(OptoReg::as_OptoReg(r10->as_VMReg()));
599 caller_saved.Insert(OptoReg::as_OptoReg(r11->as_VMReg()));
600
601 if (UseAPX) {
602 caller_saved.Insert(OptoReg::as_OptoReg(r16->as_VMReg()));
603 caller_saved.Insert(OptoReg::as_OptoReg(r17->as_VMReg()));
604 caller_saved.Insert(OptoReg::as_OptoReg(r18->as_VMReg()));
605 caller_saved.Insert(OptoReg::as_OptoReg(r19->as_VMReg()));
606 caller_saved.Insert(OptoReg::as_OptoReg(r20->as_VMReg()));
607 caller_saved.Insert(OptoReg::as_OptoReg(r21->as_VMReg()));
608 caller_saved.Insert(OptoReg::as_OptoReg(r22->as_VMReg()));
609 caller_saved.Insert(OptoReg::as_OptoReg(r23->as_VMReg()));
610 caller_saved.Insert(OptoReg::as_OptoReg(r24->as_VMReg()));
611 caller_saved.Insert(OptoReg::as_OptoReg(r25->as_VMReg()));
612 caller_saved.Insert(OptoReg::as_OptoReg(r26->as_VMReg()));
613 caller_saved.Insert(OptoReg::as_OptoReg(r27->as_VMReg()));
614 caller_saved.Insert(OptoReg::as_OptoReg(r28->as_VMReg()));
615 caller_saved.Insert(OptoReg::as_OptoReg(r29->as_VMReg()));
616 caller_saved.Insert(OptoReg::as_OptoReg(r30->as_VMReg()));
617 caller_saved.Insert(OptoReg::as_OptoReg(r31->as_VMReg()));
618 }
619
620 int gp_spill_size = 0;
621 int opmask_spill_size = 0;
622 int xmm_spill_size = 0;
623
624 // Record registers that needs to be saved/restored
625 RegMaskIterator rmi(stub->preserve_set());
626 while (rmi.has_next()) {
627 const OptoReg::Name opto_reg = rmi.next();
628 const VMReg vm_reg = OptoReg::as_VMReg(opto_reg);
629
630 if (vm_reg->is_Register()) {
631 if (caller_saved.Member(opto_reg)) {
632 _gp_registers.append(vm_reg->as_Register());
633 gp_spill_size += 8;
634 }
635 } else if (vm_reg->is_KRegister()) {
636 // All opmask registers are caller saved, thus spill the ones
637 // which are live.
638 if (_opmask_registers.find(vm_reg->as_KRegister()) == -1) {
639 _opmask_registers.append(vm_reg->as_KRegister());
640 opmask_spill_size += 8;
641 }
642 } else if (vm_reg->is_XMMRegister()) {
643 // We encode in the low order 4 bits of the opto_reg, how large part of the register is live
644 const VMReg vm_reg_base = OptoReg::as_VMReg(opto_reg & ~15);
645 const int reg_size = xmm_slot_size(opto_reg);
646 const XMMRegisterData reg_data = { vm_reg_base->as_XMMRegister(), reg_size };
647 const int reg_index = _xmm_registers.find(reg_data);
648 if (reg_index == -1) {
649 // Not previously appended
650 _xmm_registers.append(reg_data);
651 xmm_spill_size += reg_size;
652 } else {
653 // Previously appended, update size
654 const int reg_size_prev = _xmm_registers.at(reg_index)._size;
655 if (reg_size > reg_size_prev) {
656 _xmm_registers.at_put(reg_index, reg_data);
657 xmm_spill_size += reg_size - reg_size_prev;
658 }
659 }
660 } else {
661 fatal("Unexpected register type");
662 }
663 }
664
665 // Sort by size, largest first
666 _xmm_registers.sort(xmm_compare_register_size);
667
668 // On Windows, the caller reserves stack space for spilling register arguments
669 const int arg_spill_size = frame::arg_reg_save_area_bytes;
670
671 // Stack pointer must be 16 bytes aligned for the call
672 _spill_offset = _spill_size = align_up(xmm_spill_size + gp_spill_size + opmask_spill_size + arg_spill_size, 16);
673 }
674
675 SaveLiveRegisters::SaveLiveRegisters(MacroAssembler* masm, BarrierStubC2* stub)
676 : _masm(masm),
677 _gp_registers(),
678 _opmask_registers(),
679 _xmm_registers(),
680 _spill_size(0),
681 _spill_offset(0) {
682
683 //
684 // Stack layout after registers have been spilled:
685 //
686 // | ... | original rsp, 16 bytes aligned
687 // ------------------
688 // | zmm0 high |
689 // | ... |
690 // | zmm0 low | 16 bytes aligned
691 // | ... |
692 // | ymm1 high |
693 // | ... |
694 // | ymm1 low | 16 bytes aligned
695 // | ... |
696 // | xmmN high |
697 // | ... |
698 // | xmmN low | 8 bytes aligned
699 // | reg0 | 8 bytes aligned
700 // | reg1 |
701 // | ... |
702 // | regN | new rsp, if 16 bytes aligned
703 // | <padding> | else new rsp, 16 bytes aligned
704 // ------------------
705 //
706
707 // Figure out what registers to save/restore
708 initialize(stub);
709
710 // Allocate stack space
711 if (_spill_size > 0) {
712 __ subptr(rsp, _spill_size);
713 }
714
715 // Save XMM/YMM/ZMM registers
716 for (int i = 0; i < _xmm_registers.length(); i++) {
717 xmm_register_save(_xmm_registers.at(i));
718 }
719
720 if (xmm_needs_vzeroupper()) {
721 __ vzeroupper();
722 }
723
724 // Save general purpose registers
725 for (int i = 0; i < _gp_registers.length(); i++) {
726 gp_register_save(_gp_registers.at(i));
727 }
728
729 // Save opmask registers
730 for (int i = 0; i < _opmask_registers.length(); i++) {
731 opmask_register_save(_opmask_registers.at(i));
732 }
733 }
734
735 SaveLiveRegisters::~SaveLiveRegisters() {
736 // Restore opmask registers
737 for (int i = _opmask_registers.length() - 1; i >= 0; i--) {
738 opmask_register_restore(_opmask_registers.at(i));
739 }
740
741 // Restore general purpose registers
742 for (int i = _gp_registers.length() - 1; i >= 0; i--) {
743 gp_register_restore(_gp_registers.at(i));
744 }
745
746 __ vzeroupper();
747
748 // Restore XMM/YMM/ZMM registers
749 for (int i = _xmm_registers.length() - 1; i >= 0; i--) {
750 xmm_register_restore(_xmm_registers.at(i));
751 }
752
753 // Free stack space
754 if (_spill_size > 0) {
755 __ addptr(rsp, _spill_size);
756 }
757 }
758
759 #else // !_LP64
760
761 OptoReg::Name BarrierSetAssembler::refine_register(const Node* node, OptoReg::Name opto_reg) {
762 Unimplemented(); // This must be implemented to support late barrier expansion.
763 }
764
765 #endif // _LP64
766
767 #endif // COMPILER2