1 /*
2 * Copyright (c) 2012, 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 "gc/shared/barrierSet.hpp"
26 #include "gc/shared/tlab_globals.hpp"
27 #include "opto/arraycopynode.hpp"
28 #include "oops/objArrayKlass.hpp"
29 #include "opto/convertnode.hpp"
30 #include "opto/vectornode.hpp"
31 #include "opto/graphKit.hpp"
32 #include "opto/macro.hpp"
33 #include "opto/runtime.hpp"
34 #include "opto/castnode.hpp"
35 #include "runtime/stubRoutines.hpp"
36 #include "utilities/align.hpp"
37 #include "utilities/powerOfTwo.hpp"
38
39 void PhaseMacroExpand::insert_mem_bar(Node** ctrl, Node** mem, int opcode, int alias_idx, Node* precedent) {
40 MemBarNode* mb = MemBarNode::make(C, opcode, alias_idx, precedent);
41 mb->init_req(TypeFunc::Control, *ctrl);
42 mb->init_req(TypeFunc::Memory, *mem);
43 transform_later(mb);
44 *ctrl = new ProjNode(mb,TypeFunc::Control);
45 transform_later(*ctrl);
46 Node* mem_proj = new ProjNode(mb,TypeFunc::Memory);
47 transform_later(mem_proj);
48 if (alias_idx == Compile::AliasIdxBot) {
49 *mem = mem_proj;
50 } else {
51 MergeMemNode* mm = (*mem)->clone()->as_MergeMem();
52 mm->set_memory_at(alias_idx, mem_proj);
53 transform_later(mm);
54 *mem = mm;
55 }
56 }
57
58 Node* PhaseMacroExpand::array_element_address(Node* ary, Node* idx, BasicType elembt) {
59 uint shift = exact_log2(type2aelembytes(elembt));
60 uint header = arrayOopDesc::base_offset_in_bytes(elembt);
61 Node* base = basic_plus_adr(ary, header);
62 #ifdef _LP64
63 // see comment in GraphKit::array_element_address
64 int index_max = max_jint - 1; // array size is max_jint, index is one less
65 const TypeLong* lidxtype = TypeLong::make(CONST64(0), index_max, Type::WidenMax);
66 idx = transform_later( new ConvI2LNode(idx, lidxtype) );
67 #endif
68 Node* scale = new LShiftXNode(idx, intcon(shift));
69 transform_later(scale);
70 return basic_plus_adr(ary, base, scale);
71 }
72
73 Node* PhaseMacroExpand::ConvI2L(Node* offset) {
74 return transform_later(new ConvI2LNode(offset));
75 }
76
77 Node* PhaseMacroExpand::make_leaf_call(Node* ctrl, Node* mem,
78 const TypeFunc* call_type, address call_addr,
79 const char* call_name,
80 const TypePtr* adr_type,
81 Node* parm0, Node* parm1,
82 Node* parm2, Node* parm3,
83 Node* parm4, Node* parm5,
84 Node* parm6, Node* parm7) {
85 Node* call = new CallLeafNoFPNode(call_type, call_addr, call_name, adr_type);
86 call->init_req(TypeFunc::Control, ctrl);
87 call->init_req(TypeFunc::I_O , top());
88 call->init_req(TypeFunc::Memory , mem);
89 call->init_req(TypeFunc::ReturnAdr, top());
90 call->init_req(TypeFunc::FramePtr, top());
91
92 // Hook each parm in order. Stop looking at the first null.
93 if (parm0 != nullptr) { call->init_req(TypeFunc::Parms+0, parm0);
94 if (parm1 != nullptr) { call->init_req(TypeFunc::Parms+1, parm1);
95 if (parm2 != nullptr) { call->init_req(TypeFunc::Parms+2, parm2);
96 if (parm3 != nullptr) { call->init_req(TypeFunc::Parms+3, parm3);
97 if (parm4 != nullptr) { call->init_req(TypeFunc::Parms+4, parm4);
98 if (parm5 != nullptr) { call->init_req(TypeFunc::Parms+5, parm5);
99 if (parm6 != nullptr) { call->init_req(TypeFunc::Parms+6, parm6);
100 if (parm7 != nullptr) { call->init_req(TypeFunc::Parms+7, parm7);
101 /* close each nested if ===> */ } } } } } } } }
102 assert(call->in(call->req()-1) != nullptr, "must initialize all parms");
103
104 return call;
105 }
106
107
108 //------------------------------generate_guard---------------------------
109 // Helper function for generating guarded fast-slow graph structures.
110 // The given 'test', if true, guards a slow path. If the test fails
111 // then a fast path can be taken. (We generally hope it fails.)
112 // In all cases, GraphKit::control() is updated to the fast path.
113 // The returned value represents the control for the slow path.
114 // The return value is never 'top'; it is either a valid control
115 // or null if it is obvious that the slow path can never be taken.
116 // Also, if region and the slow control are not null, the slow edge
117 // is appended to the region.
118 Node* PhaseMacroExpand::generate_guard(Node** ctrl, Node* test, RegionNode* region, float true_prob) {
119 if ((*ctrl)->is_top()) {
120 // Already short circuited.
121 return nullptr;
122 }
123 // Build an if node and its projections.
124 // If test is true we take the slow path, which we assume is uncommon.
125 if (_igvn.type(test) == TypeInt::ZERO) {
126 // The slow branch is never taken. No need to build this guard.
127 return nullptr;
128 }
129
130 IfNode* iff = new IfNode(*ctrl, test, true_prob, COUNT_UNKNOWN);
131 transform_later(iff);
132
133 Node* if_slow = new IfTrueNode(iff);
134 transform_later(if_slow);
135
136 if (region != nullptr) {
137 region->add_req(if_slow);
138 }
139
140 Node* if_fast = new IfFalseNode(iff);
141 transform_later(if_fast);
142
143 *ctrl = if_fast;
144
145 return if_slow;
146 }
147
148 inline Node* PhaseMacroExpand::generate_slow_guard(Node** ctrl, Node* test, RegionNode* region) {
149 return generate_guard(ctrl, test, region, PROB_UNLIKELY_MAG(3));
150 }
151
152 void PhaseMacroExpand::generate_negative_guard(Node** ctrl, Node* index, RegionNode* region) {
153 if ((*ctrl)->is_top())
154 return; // already stopped
155 if (_igvn.type(index)->higher_equal(TypeInt::POS)) // [0,maxint]
156 return; // index is already adequately typed
157 Node* cmp_lt = new CmpINode(index, intcon(0));
158 transform_later(cmp_lt);
159 Node* bol_lt = new BoolNode(cmp_lt, BoolTest::lt);
160 transform_later(bol_lt);
161 generate_guard(ctrl, bol_lt, region, PROB_MIN);
162 }
163
164 void PhaseMacroExpand::generate_limit_guard(Node** ctrl, Node* offset, Node* subseq_length, Node* array_length, RegionNode* region) {
165 if ((*ctrl)->is_top())
166 return; // already stopped
167 bool zero_offset = _igvn.type(offset) == TypeInt::ZERO;
168 if (zero_offset && subseq_length->eqv_uncast(array_length))
169 return; // common case of whole-array copy
170 Node* last = subseq_length;
171 if (!zero_offset) { // last += offset
172 last = new AddINode(last, offset);
173 transform_later(last);
174 }
175 Node* cmp_lt = new CmpUNode(array_length, last);
176 transform_later(cmp_lt);
177 Node* bol_lt = new BoolNode(cmp_lt, BoolTest::lt);
178 transform_later(bol_lt);
179 generate_guard(ctrl, bol_lt, region, PROB_MIN);
180 }
181
182 //
183 // Partial in-lining handling for smaller conjoint/disjoint array copies having
184 // length(in bytes) less than ArrayOperationPartialInlineSize.
185 // if (length <= ArrayOperationPartialInlineSize) {
186 // partial_inlining_block:
187 // mask = Mask_Gen
188 // vload = LoadVectorMasked src , mask
189 // StoreVectorMasked dst, mask, vload
190 // } else {
191 // stub_block:
192 // callstub array_copy
193 // }
194 // exit_block:
195 // Phi = label partial_inlining_block:mem , label stub_block:mem (filled by caller)
196 // mem = MergeMem (Phi)
197 // control = stub_block
198 //
199 // Exit_block and associated phi(memory) are partially initialized for partial_in-lining_block
200 // edges. Remaining edges for exit_block coming from stub_block are connected by the caller
201 // post stub nodes creation.
202 //
203
204 void PhaseMacroExpand::generate_partial_inlining_block(Node** ctrl, MergeMemNode** mem, const TypePtr* adr_type,
205 RegionNode** exit_block, Node** result_memory, Node* length,
206 Node* src_start, Node* dst_start, BasicType type) {
207 const TypePtr *src_adr_type = _igvn.type(src_start)->isa_ptr();
208 Node* inline_block = nullptr;
209 Node* stub_block = nullptr;
210
211 int const_len = -1;
212 const TypeInt* lty = nullptr;
213 uint shift = exact_log2(type2aelembytes(type));
214 if (length->Opcode() == Op_ConvI2L) {
215 lty = _igvn.type(length->in(1))->isa_int();
216 } else {
217 lty = _igvn.type(length)->isa_int();
218 }
219 if (lty && lty->is_con()) {
220 const_len = lty->get_con() << shift;
221 }
222
223 // Return if copy length is greater than partial inline size limit or
224 // target does not supports masked load/stores.
225 int lane_count = ArrayCopyNode::get_partial_inline_vector_lane_count(type, const_len);
226 if ( const_len > ArrayOperationPartialInlineSize ||
227 !Matcher::match_rule_supported_vector(Op_LoadVectorMasked, lane_count, type) ||
228 !Matcher::match_rule_supported_vector(Op_StoreVectorMasked, lane_count, type) ||
229 !Matcher::match_rule_supported_vector(Op_VectorMaskGen, lane_count, type)) {
230 return;
231 }
232
233 int inline_limit = ArrayOperationPartialInlineSize / type2aelembytes(type);
234 Node* casted_length = new CastLLNode(*ctrl, length, TypeLong::make(0, inline_limit, Type::WidenMin));
235 transform_later(casted_length);
236 Node* copy_bytes = new LShiftXNode(length, intcon(shift));
237 transform_later(copy_bytes);
238
239 Node* cmp_le = new CmpULNode(copy_bytes, longcon(ArrayOperationPartialInlineSize));
240 transform_later(cmp_le);
241 Node* bol_le = new BoolNode(cmp_le, BoolTest::le);
242 transform_later(bol_le);
243 inline_block = generate_guard(ctrl, bol_le, nullptr, PROB_FAIR);
244 stub_block = *ctrl;
245
246 Node* mask_gen = VectorMaskGenNode::make(casted_length, type);
247 transform_later(mask_gen);
248
249 unsigned vec_size = lane_count * type2aelembytes(type);
250 if (C->max_vector_size() < vec_size) {
251 C->set_max_vector_size(vec_size);
252 }
253
254 const TypeVect * vt = TypeVect::make(type, lane_count);
255 Node* mm = (*mem)->memory_at(C->get_alias_index(src_adr_type));
256 Node* masked_load = new LoadVectorMaskedNode(inline_block, mm, src_start,
257 src_adr_type, vt, mask_gen);
258 transform_later(masked_load);
259
260 mm = (*mem)->memory_at(C->get_alias_index(adr_type));
261 Node* masked_store = new StoreVectorMaskedNode(inline_block, mm, dst_start,
262 masked_load, adr_type, mask_gen);
263 transform_later(masked_store);
264
265 // Convergence region for inline_block and stub_block.
266 *exit_block = new RegionNode(3);
267 transform_later(*exit_block);
268 (*exit_block)->init_req(1, inline_block);
269 *result_memory = new PhiNode(*exit_block, Type::MEMORY, adr_type);
270 transform_later(*result_memory);
271 (*result_memory)->init_req(1, masked_store);
272
273 *ctrl = stub_block;
274 }
275
276
277 Node* PhaseMacroExpand::generate_nonpositive_guard(Node** ctrl, Node* index, bool never_negative) {
278 if ((*ctrl)->is_top()) return nullptr;
279
280 if (_igvn.type(index)->higher_equal(TypeInt::POS1)) // [1,maxint]
281 return nullptr; // index is already adequately typed
282 Node* cmp_le = new CmpINode(index, intcon(0));
283 transform_later(cmp_le);
284 BoolTest::mask le_or_eq = (never_negative ? BoolTest::eq : BoolTest::le);
285 Node* bol_le = new BoolNode(cmp_le, le_or_eq);
286 transform_later(bol_le);
287 Node* is_notp = generate_guard(ctrl, bol_le, nullptr, PROB_MIN);
288
289 return is_notp;
290 }
291
292 void PhaseMacroExpand::finish_arraycopy_call(Node* call, Node** ctrl, MergeMemNode** mem, const TypePtr* adr_type) {
293 transform_later(call);
294
295 *ctrl = new ProjNode(call,TypeFunc::Control);
296 transform_later(*ctrl);
297 Node* newmem = new ProjNode(call, TypeFunc::Memory);
298 transform_later(newmem);
299
300 uint alias_idx = C->get_alias_index(adr_type);
301 if (alias_idx != Compile::AliasIdxBot) {
302 *mem = MergeMemNode::make(*mem);
303 (*mem)->set_memory_at(alias_idx, newmem);
304 } else {
305 *mem = MergeMemNode::make(newmem);
306 }
307 transform_later(*mem);
308 }
309
310 address PhaseMacroExpand::basictype2arraycopy(BasicType t,
311 Node* src_offset,
312 Node* dest_offset,
313 bool disjoint_bases,
314 const char* &name,
315 bool dest_uninitialized) {
316 const TypeInt* src_offset_inttype = _igvn.find_int_type(src_offset);
317 const TypeInt* dest_offset_inttype = _igvn.find_int_type(dest_offset);
318
319 bool aligned = false;
320 bool disjoint = disjoint_bases;
321
322 // if the offsets are the same, we can treat the memory regions as
323 // disjoint, because either the memory regions are in different arrays,
324 // or they are identical (which we can treat as disjoint.) We can also
325 // treat a copy with a destination index less that the source index
326 // as disjoint since a low->high copy will work correctly in this case.
327 if (src_offset_inttype != nullptr && src_offset_inttype->is_con() &&
328 dest_offset_inttype != nullptr && dest_offset_inttype->is_con()) {
329 // both indices are constants
330 int s_offs = src_offset_inttype->get_con();
331 int d_offs = dest_offset_inttype->get_con();
332 int element_size = type2aelembytes(t);
333 aligned = ((arrayOopDesc::base_offset_in_bytes(t) + (uint)s_offs * element_size) % HeapWordSize == 0) &&
334 ((arrayOopDesc::base_offset_in_bytes(t) + (uint)d_offs * element_size) % HeapWordSize == 0);
335 if (s_offs >= d_offs) disjoint = true;
336 } else if (src_offset == dest_offset && src_offset != nullptr) {
337 // This can occur if the offsets are identical non-constants.
338 disjoint = true;
339 }
340
341 return StubRoutines::select_arraycopy_function(t, aligned, disjoint, name, dest_uninitialized);
342 }
343
344 #define XTOP LP64_ONLY(COMMA top())
345
346 // Generate an optimized call to arraycopy.
347 // Caller must guard against non-arrays.
348 // Caller must determine a common array basic-type for both arrays.
349 // Caller must validate offsets against array bounds.
350 // The slow_region has already collected guard failure paths
351 // (such as out of bounds length or non-conformable array types).
352 // The generated code has this shape, in general:
353 //
354 // if (length == 0) return // via zero_path
355 // slowval = -1
356 // if (types unknown) {
357 // slowval = call generic copy loop
358 // if (slowval == 0) return // via checked_path
359 // } else if (indexes in bounds) {
360 // if ((is object array) && !(array type check)) {
361 // slowval = call checked copy loop
362 // if (slowval == 0) return // via checked_path
363 // } else {
364 // call bulk copy loop
365 // return // via fast_path
366 // }
367 // }
368 // // adjust params for remaining work:
369 // if (slowval != -1) {
370 // n = -1^slowval; src_offset += n; dest_offset += n; length -= n
371 // }
372 // slow_region:
373 // call slow arraycopy(src, src_offset, dest, dest_offset, length)
374 // return // via slow_call_path
375 //
376 // This routine is used from several intrinsics: System.arraycopy,
377 // Object.clone (the array subcase), and Arrays.copyOf[Range].
378 //
379 Node* PhaseMacroExpand::generate_arraycopy(ArrayCopyNode *ac, AllocateArrayNode* alloc,
380 Node** ctrl, MergeMemNode* mem, Node** io,
381 const TypePtr* adr_type,
382 BasicType basic_elem_type,
383 Node* src, Node* src_offset,
384 Node* dest, Node* dest_offset,
385 Node* copy_length,
386 bool disjoint_bases,
387 bool length_never_negative,
388 RegionNode* slow_region) {
389 if (slow_region == nullptr) {
390 slow_region = new RegionNode(1);
391 transform_later(slow_region);
392 }
393
394 Node* original_dest = dest;
395 bool dest_needs_zeroing = false;
396 bool acopy_to_uninitialized = false;
397
398 // See if this is the initialization of a newly-allocated array.
399 // If so, we will take responsibility here for initializing it to zero.
400 // (Note: Because tightly_coupled_allocation performs checks on the
401 // out-edges of the dest, we need to avoid making derived pointers
402 // from it until we have checked its uses.)
403 if (ReduceBulkZeroing
404 && !(UseTLAB && ZeroTLAB) // pointless if already zeroed
405 && basic_elem_type != T_CONFLICT // avoid corner case
406 && !src->eqv_uncast(dest)
407 && alloc != nullptr
408 && _igvn.find_int_con(alloc->in(AllocateNode::ALength), 1) > 0) {
409 assert(ac->is_alloc_tightly_coupled(), "sanity");
410 // acopy to uninitialized tightly coupled allocations
411 // needs zeroing outside the copy range
412 // and the acopy itself will be to uninitialized memory
413 acopy_to_uninitialized = true;
414 if (alloc->maybe_set_complete(&_igvn)) {
415 // "You break it, you buy it."
416 InitializeNode* init = alloc->initialization();
417 assert(init->is_complete(), "we just did this");
418 init->set_complete_with_arraycopy();
419 assert(dest->is_CheckCastPP(), "sanity");
420 assert(dest->in(0)->in(0) == init, "dest pinned");
421 adr_type = TypeRawPtr::BOTTOM; // all initializations are into raw memory
422 // From this point on, every exit path is responsible for
423 // initializing any non-copied parts of the object to zero.
424 // Also, if this flag is set we make sure that arraycopy interacts properly
425 // with G1, eliding pre-barriers. See CR 6627983.
426 dest_needs_zeroing = true;
427 } else {
428 // dest_need_zeroing = false;
429 }
430 } else {
431 // No zeroing elimination needed here.
432 alloc = nullptr;
433 acopy_to_uninitialized = false;
434 //original_dest = dest;
435 //dest_needs_zeroing = false;
436 }
437
438 uint alias_idx = C->get_alias_index(adr_type);
439
440 // Results are placed here:
441 enum { fast_path = 1, // normal void-returning assembly stub
442 checked_path = 2, // special assembly stub with cleanup
443 slow_call_path = 3, // something went wrong; call the VM
444 zero_path = 4, // bypass when length of copy is zero
445 bcopy_path = 5, // copy primitive array by 64-bit blocks
446 PATH_LIMIT = 6
447 };
448 RegionNode* result_region = new RegionNode(PATH_LIMIT);
449 PhiNode* result_i_o = new PhiNode(result_region, Type::ABIO);
450 PhiNode* result_memory = new PhiNode(result_region, Type::MEMORY, adr_type);
451 assert(adr_type != TypePtr::BOTTOM, "must be RawMem or a T[] slice");
452 transform_later(result_region);
453 transform_later(result_i_o);
454 transform_later(result_memory);
455
456 // The slow_control path:
457 Node* slow_control;
458 Node* slow_i_o = *io;
459 Node* slow_mem = mem->memory_at(alias_idx);
460 DEBUG_ONLY(slow_control = (Node*) badAddress);
461
462 // Checked control path:
463 Node* checked_control = top();
464 Node* checked_mem = nullptr;
465 Node* checked_i_o = nullptr;
466 Node* checked_value = nullptr;
467
468 if (basic_elem_type == T_CONFLICT) {
469 assert(!dest_needs_zeroing, "");
470 Node* cv = generate_generic_arraycopy(ctrl, &mem,
471 adr_type,
472 src, src_offset, dest, dest_offset,
473 copy_length, acopy_to_uninitialized);
474 if (cv == nullptr) cv = intcon(-1); // failure (no stub available)
475 checked_control = *ctrl;
476 checked_i_o = *io;
477 checked_mem = mem->memory_at(alias_idx);
478 checked_value = cv;
479 *ctrl = top();
480 }
481
482 Node* not_pos = generate_nonpositive_guard(ctrl, copy_length, length_never_negative);
483 if (not_pos != nullptr) {
484 Node* local_ctrl = not_pos, *local_io = *io;
485 MergeMemNode* local_mem = MergeMemNode::make(mem);
486 transform_later(local_mem);
487
488 // (6) length must not be negative.
489 if (!length_never_negative) {
490 generate_negative_guard(&local_ctrl, copy_length, slow_region);
491 }
492
493 // copy_length is 0.
494 if (dest_needs_zeroing) {
495 assert(!local_ctrl->is_top(), "no ctrl?");
496 Node* dest_length = alloc->in(AllocateNode::ALength);
497 if (copy_length->eqv_uncast(dest_length)
498 || _igvn.find_int_con(dest_length, 1) <= 0) {
499 // There is no zeroing to do. No need for a secondary raw memory barrier.
500 } else {
501 // Clear the whole thing since there are no source elements to copy.
502 generate_clear_array(local_ctrl, local_mem,
503 adr_type, dest, basic_elem_type,
504 intcon(0), nullptr,
505 alloc->in(AllocateNode::AllocSize));
506 // Use a secondary InitializeNode as raw memory barrier.
507 // Currently it is needed only on this path since other
508 // paths have stub or runtime calls as raw memory barriers.
509 MemBarNode* mb = MemBarNode::make(C, Op_Initialize,
510 Compile::AliasIdxRaw,
511 top());
512 transform_later(mb);
513 mb->set_req(TypeFunc::Control,local_ctrl);
514 mb->set_req(TypeFunc::Memory, local_mem->memory_at(Compile::AliasIdxRaw));
515 local_ctrl = transform_later(new ProjNode(mb, TypeFunc::Control));
516 local_mem->set_memory_at(Compile::AliasIdxRaw, transform_later(new ProjNode(mb, TypeFunc::Memory)));
517
518 InitializeNode* init = mb->as_Initialize();
519 init->set_complete(&_igvn); // (there is no corresponding AllocateNode)
520 }
521 }
522
523 // Present the results of the fast call.
524 result_region->init_req(zero_path, local_ctrl);
525 result_i_o ->init_req(zero_path, local_io);
526 result_memory->init_req(zero_path, local_mem->memory_at(alias_idx));
527 }
528
529 if (!(*ctrl)->is_top() && dest_needs_zeroing) {
530 // We have to initialize the *uncopied* part of the array to zero.
531 // The copy destination is the slice dest[off..off+len]. The other slices
532 // are dest_head = dest[0..off] and dest_tail = dest[off+len..dest.length].
533 Node* dest_size = alloc->in(AllocateNode::AllocSize);
534 Node* dest_length = alloc->in(AllocateNode::ALength);
535 Node* dest_tail = transform_later( new AddINode(dest_offset, copy_length));
536
537 // If there is a head section that needs zeroing, do it now.
538 if (_igvn.find_int_con(dest_offset, -1) != 0) {
539 generate_clear_array(*ctrl, mem,
540 adr_type, dest, basic_elem_type,
541 intcon(0), dest_offset,
542 nullptr);
543 }
544
545 // Next, perform a dynamic check on the tail length.
546 // It is often zero, and we can win big if we prove this.
547 // There are two wins: Avoid generating the ClearArray
548 // with its attendant messy index arithmetic, and upgrade
549 // the copy to a more hardware-friendly word size of 64 bits.
550 Node* tail_ctl = nullptr;
551 if (!(*ctrl)->is_top() && !dest_tail->eqv_uncast(dest_length)) {
552 Node* cmp_lt = transform_later( new CmpINode(dest_tail, dest_length) );
553 Node* bol_lt = transform_later( new BoolNode(cmp_lt, BoolTest::lt) );
554 tail_ctl = generate_slow_guard(ctrl, bol_lt, nullptr);
555 assert(tail_ctl != nullptr || !(*ctrl)->is_top(), "must be an outcome");
556 }
557
558 // At this point, let's assume there is no tail.
559 if (!(*ctrl)->is_top() && alloc != nullptr && basic_elem_type != T_OBJECT) {
560 // There is no tail. Try an upgrade to a 64-bit copy.
561 bool didit = false;
562 {
563 Node* local_ctrl = *ctrl, *local_io = *io;
564 MergeMemNode* local_mem = MergeMemNode::make(mem);
565 transform_later(local_mem);
566
567 didit = generate_block_arraycopy(&local_ctrl, &local_mem, local_io,
568 adr_type, basic_elem_type, alloc,
569 src, src_offset, dest, dest_offset,
570 dest_size, acopy_to_uninitialized);
571 if (didit) {
572 // Present the results of the block-copying fast call.
573 result_region->init_req(bcopy_path, local_ctrl);
574 result_i_o ->init_req(bcopy_path, local_io);
575 result_memory->init_req(bcopy_path, local_mem->memory_at(alias_idx));
576 }
577 }
578 if (didit) {
579 *ctrl = top(); // no regular fast path
580 }
581 }
582
583 // Clear the tail, if any.
584 if (tail_ctl != nullptr) {
585 Node* notail_ctl = (*ctrl)->is_top() ? nullptr : *ctrl;
586 *ctrl = tail_ctl;
587 if (notail_ctl == nullptr) {
588 generate_clear_array(*ctrl, mem,
589 adr_type, dest, basic_elem_type,
590 dest_tail, nullptr,
591 dest_size);
592 } else {
593 // Make a local merge.
594 Node* done_ctl = transform_later(new RegionNode(3));
595 Node* done_mem = transform_later(new PhiNode(done_ctl, Type::MEMORY, adr_type));
596 done_ctl->init_req(1, notail_ctl);
597 done_mem->init_req(1, mem->memory_at(alias_idx));
598 generate_clear_array(*ctrl, mem,
599 adr_type, dest, basic_elem_type,
600 dest_tail, nullptr,
601 dest_size);
602 done_ctl->init_req(2, *ctrl);
603 done_mem->init_req(2, mem->memory_at(alias_idx));
604 *ctrl = done_ctl;
605 mem->set_memory_at(alias_idx, done_mem);
606 }
607 }
608 }
609
610 BasicType copy_type = basic_elem_type;
611 assert(basic_elem_type != T_ARRAY, "caller must fix this");
612 if (!(*ctrl)->is_top() && copy_type == T_OBJECT) {
613 // If src and dest have compatible element types, we can copy bits.
614 // Types S[] and D[] are compatible if D is a supertype of S.
615 //
616 // If they are not, we will use checked_oop_disjoint_arraycopy,
617 // which performs a fast optimistic per-oop check, and backs off
618 // further to JVM_ArrayCopy on the first per-oop check that fails.
619 // (Actually, we don't move raw bits only; the GC requires card marks.)
620
621 // We don't need a subtype check for validated copies and Object[].clone()
622 bool skip_subtype_check = ac->is_arraycopy_validated() || ac->is_copyof_validated() ||
623 ac->is_copyofrange_validated() || ac->is_clone_oop_array();
624 if (!skip_subtype_check) {
625 // Get the klass* for both src and dest
626 Node* src_klass = ac->in(ArrayCopyNode::SrcKlass);
627 Node* dest_klass = ac->in(ArrayCopyNode::DestKlass);
628
629 assert(src_klass != nullptr && dest_klass != nullptr, "should have klasses");
630
631 // Generate the subtype check.
632 // This might fold up statically, or then again it might not.
633 //
634 // Non-static example: Copying List<String>.elements to a new String[].
635 // The backing store for a List<String> is always an Object[],
636 // but its elements are always type String, if the generic types
637 // are correct at the source level.
638 //
639 // Test S[] against D[], not S against D, because (probably)
640 // the secondary supertype cache is less busy for S[] than S.
641 // This usually only matters when D is an interface.
642 Node* not_subtype_ctrl = Phase::gen_subtype_check(src_klass, dest_klass, ctrl, mem, _igvn, nullptr, -1);
643 // Plug failing path into checked_oop_disjoint_arraycopy
644 if (not_subtype_ctrl != top()) {
645 Node* local_ctrl = not_subtype_ctrl;
646 MergeMemNode* local_mem = MergeMemNode::make(mem);
647 transform_later(local_mem);
648
649 // (At this point we can assume disjoint_bases, since types differ.)
650 int ek_offset = in_bytes(ObjArrayKlass::element_klass_offset());
651 Node* p1 = basic_plus_adr(dest_klass, ek_offset);
652 Node* n1 = LoadKlassNode::make(_igvn, C->immutable_memory(), p1, TypeRawPtr::BOTTOM);
653 Node* dest_elem_klass = transform_later(n1);
654 Node* cv = generate_checkcast_arraycopy(&local_ctrl, &local_mem,
655 adr_type,
656 dest_elem_klass,
657 src, src_offset, dest, dest_offset,
658 ConvI2X(copy_length), acopy_to_uninitialized);
659 if (cv == nullptr) cv = intcon(-1); // failure (no stub available)
660 checked_control = local_ctrl;
661 checked_i_o = *io;
662 checked_mem = local_mem->memory_at(alias_idx);
663 checked_value = cv;
664 }
665 }
666 // At this point we know we do not need type checks on oop stores.
667
668 BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2();
669 if (!bs->array_copy_requires_gc_barriers(alloc != nullptr, copy_type, false, false, BarrierSetC2::Expansion)) {
670 // If we do not need gc barriers, copy using the jint or jlong stub.
671 copy_type = LP64_ONLY(UseCompressedOops ? T_INT : T_LONG) NOT_LP64(T_INT);
672 assert(type2aelembytes(basic_elem_type) == type2aelembytes(copy_type),
673 "sizes agree");
674 }
675 }
676
677 if (!(*ctrl)->is_top()) {
678 // Generate the fast path, if possible.
679 Node* local_ctrl = *ctrl;
680 MergeMemNode* local_mem = MergeMemNode::make(mem);
681 transform_later(local_mem);
682 generate_unchecked_arraycopy(&local_ctrl, &local_mem,
683 adr_type, copy_type, disjoint_bases,
684 src, src_offset, dest, dest_offset,
685 ConvI2X(copy_length), acopy_to_uninitialized);
686
687 // Present the results of the fast call.
688 result_region->init_req(fast_path, local_ctrl);
689 result_i_o ->init_req(fast_path, *io);
690 result_memory->init_req(fast_path, local_mem->memory_at(alias_idx));
691 }
692
693 // Here are all the slow paths up to this point, in one bundle:
694 assert(slow_region != nullptr, "allocated on entry");
695 slow_control = slow_region;
696 DEBUG_ONLY(slow_region = (RegionNode*)badAddress);
697
698 *ctrl = checked_control;
699 if (!(*ctrl)->is_top()) {
700 // Clean up after the checked call.
701 // The returned value is either 0 or -1^K,
702 // where K = number of partially transferred array elements.
703 Node* cmp = new CmpINode(checked_value, intcon(0));
704 transform_later(cmp);
705 Node* bol = new BoolNode(cmp, BoolTest::eq);
706 transform_later(bol);
707 IfNode* iff = new IfNode(*ctrl, bol, PROB_MAX, COUNT_UNKNOWN);
708 transform_later(iff);
709
710 // If it is 0, we are done, so transfer to the end.
711 Node* checks_done = new IfTrueNode(iff);
712 transform_later(checks_done);
713 result_region->init_req(checked_path, checks_done);
714 result_i_o ->init_req(checked_path, checked_i_o);
715 result_memory->init_req(checked_path, checked_mem);
716
717 // If it is not zero, merge into the slow call.
718 *ctrl = new IfFalseNode(iff);
719 transform_later(*ctrl);
720 RegionNode* slow_reg2 = new RegionNode(3);
721 PhiNode* slow_i_o2 = new PhiNode(slow_reg2, Type::ABIO);
722 PhiNode* slow_mem2 = new PhiNode(slow_reg2, Type::MEMORY, adr_type);
723 transform_later(slow_reg2);
724 transform_later(slow_i_o2);
725 transform_later(slow_mem2);
726 slow_reg2 ->init_req(1, slow_control);
727 slow_i_o2 ->init_req(1, slow_i_o);
728 slow_mem2 ->init_req(1, slow_mem);
729 slow_reg2 ->init_req(2, *ctrl);
730 slow_i_o2 ->init_req(2, checked_i_o);
731 slow_mem2 ->init_req(2, checked_mem);
732
733 slow_control = slow_reg2;
734 slow_i_o = slow_i_o2;
735 slow_mem = slow_mem2;
736
737 if (alloc != nullptr) {
738 // We'll restart from the very beginning, after zeroing the whole thing.
739 // This can cause double writes, but that's OK since dest is brand new.
740 // So we ignore the low 31 bits of the value returned from the stub.
741 } else {
742 // We must continue the copy exactly where it failed, or else
743 // another thread might see the wrong number of writes to dest.
744 Node* checked_offset = new XorINode(checked_value, intcon(-1));
745 Node* slow_offset = new PhiNode(slow_reg2, TypeInt::INT);
746 transform_later(checked_offset);
747 transform_later(slow_offset);
748 slow_offset->init_req(1, intcon(0));
749 slow_offset->init_req(2, checked_offset);
750
751 // Adjust the arguments by the conditionally incoming offset.
752 Node* src_off_plus = new AddINode(src_offset, slow_offset);
753 transform_later(src_off_plus);
754 Node* dest_off_plus = new AddINode(dest_offset, slow_offset);
755 transform_later(dest_off_plus);
756 Node* length_minus = new SubINode(copy_length, slow_offset);
757 transform_later(length_minus);
758
759 // Tweak the node variables to adjust the code produced below:
760 src_offset = src_off_plus;
761 dest_offset = dest_off_plus;
762 copy_length = length_minus;
763 }
764 }
765 *ctrl = slow_control;
766 if (!(*ctrl)->is_top()) {
767 Node* local_ctrl = *ctrl, *local_io = slow_i_o;
768 MergeMemNode* local_mem = MergeMemNode::make(mem);
769 transform_later(local_mem);
770
771 // Generate the slow path, if needed.
772 local_mem->set_memory_at(alias_idx, slow_mem);
773
774 if (dest_needs_zeroing) {
775 generate_clear_array(local_ctrl, local_mem,
776 adr_type, dest, basic_elem_type,
777 intcon(0), nullptr,
778 alloc->in(AllocateNode::AllocSize));
779 }
780
781 local_mem = generate_slow_arraycopy(ac,
782 &local_ctrl, local_mem, &local_io,
783 adr_type,
784 src, src_offset, dest, dest_offset,
785 copy_length, /*dest_uninitialized*/false);
786
787 result_region->init_req(slow_call_path, local_ctrl);
788 result_i_o ->init_req(slow_call_path, local_io);
789 result_memory->init_req(slow_call_path, local_mem->memory_at(alias_idx));
790 } else {
791 ShouldNotReachHere(); // no call to generate_slow_arraycopy:
792 // projections were not extracted
793 }
794
795 // Remove unused edges.
796 for (uint i = 1; i < result_region->req(); i++) {
797 if (result_region->in(i) == nullptr) {
798 result_region->init_req(i, top());
799 }
800 }
801
802 // Finished; return the combined state.
803 *ctrl = result_region;
804 *io = result_i_o;
805 mem->set_memory_at(alias_idx, result_memory);
806
807 // mem no longer guaranteed to stay a MergeMemNode
808 Node* out_mem = mem;
809 DEBUG_ONLY(mem = nullptr);
810
811 // The memory edges above are precise in order to model effects around
812 // array copies accurately to allow value numbering of field loads around
813 // arraycopy. Such field loads, both before and after, are common in Java
814 // collections and similar classes involving header/array data structures.
815 //
816 // But with low number of register or when some registers are used or killed
817 // by arraycopy calls it causes registers spilling on stack. See 6544710.
818 // The next memory barrier is added to avoid it. If the arraycopy can be
819 // optimized away (which it can, sometimes) then we can manually remove
820 // the membar also.
821 //
822 // Do not let reads from the cloned object float above the arraycopy.
823 if (alloc != nullptr && !alloc->initialization()->does_not_escape()) {
824 // Do not let stores that initialize this object be reordered with
825 // a subsequent store that would make this object accessible by
826 // other threads.
827 assert(ac->_dest_type == TypeOopPtr::BOTTOM, "non escaping destination shouldn't have narrow slice");
828 insert_mem_bar(ctrl, &out_mem, Op_MemBarStoreStore, Compile::AliasIdxBot);
829 } else {
830 int mem_bar_alias_idx = Compile::AliasIdxBot;
831 if (ac->_dest_type != TypeOopPtr::BOTTOM) {
832 // The graph was transformed under the assumption the ArrayCopy node only had an effect on a narrow slice. We can't
833 // insert a wide membar now that it's being expanded: a load that uses the input memory state of the ArrayCopy
834 // could then become anti dependent on the membar when it was not anti dependent on the ArrayCopy leading to a
835 // broken graph.
836 mem_bar_alias_idx = C->get_alias_index(ac->_dest_type->add_offset(Type::OffsetBot)->is_ptr());
837 }
838 insert_mem_bar(ctrl, &out_mem, Op_MemBarCPUOrder, mem_bar_alias_idx);
839 }
840
841 assert((*ctrl)->is_Proj(), "MemBar control projection");
842 assert((*ctrl)->in(0)->isa_MemBar(), "MemBar node");
843 (*ctrl)->in(0)->isa_MemBar()->set_trailing_expanded_array_copy();
844
845 _igvn.replace_node(_callprojs.fallthrough_memproj, out_mem);
846 if (_callprojs.fallthrough_ioproj != nullptr) {
847 _igvn.replace_node(_callprojs.fallthrough_ioproj, *io);
848 }
849 _igvn.replace_node(_callprojs.fallthrough_catchproj, *ctrl);
850
851 #ifdef ASSERT
852 const TypeOopPtr* dest_t = _igvn.type(dest)->is_oopptr();
853 if (dest_t->is_known_instance()) {
854 ArrayCopyNode* ac = nullptr;
855 assert(ArrayCopyNode::may_modify(dest_t, (*ctrl)->in(0)->as_MemBar(), &_igvn, ac), "dependency on arraycopy lost");
856 assert(ac == nullptr, "no arraycopy anymore");
857 }
858 #endif
859
860 return out_mem;
861 }
862
863 // Helper for initialization of arrays, creating a ClearArray.
864 // It writes zero bits in [start..end), within the body of an array object.
865 // The memory effects are all chained onto the 'adr_type' alias category.
866 //
867 // Since the object is otherwise uninitialized, we are free
868 // to put a little "slop" around the edges of the cleared area,
869 // as long as it does not go back into the array's header,
870 // or beyond the array end within the heap.
871 //
872 // The lower edge can be rounded down to the nearest jint and the
873 // upper edge can be rounded up to the nearest MinObjAlignmentInBytes.
874 //
875 // Arguments:
876 // adr_type memory slice where writes are generated
877 // dest oop of the destination array
878 // basic_elem_type element type of the destination
879 // slice_idx array index of first element to store
880 // slice_len number of elements to store (or null)
881 // dest_size total size in bytes of the array object
882 //
883 // Exactly one of slice_len or dest_size must be non-null.
884 // If dest_size is non-null, zeroing extends to the end of the object.
885 // If slice_len is non-null, the slice_idx value must be a constant.
886 void PhaseMacroExpand::generate_clear_array(Node* ctrl, MergeMemNode* merge_mem,
887 const TypePtr* adr_type,
888 Node* dest,
889 BasicType basic_elem_type,
890 Node* slice_idx,
891 Node* slice_len,
892 Node* dest_size) {
893 // one or the other but not both of slice_len and dest_size:
894 assert((slice_len != nullptr? 1: 0) + (dest_size != nullptr? 1: 0) == 1, "");
895 if (slice_len == nullptr) slice_len = top();
896 if (dest_size == nullptr) dest_size = top();
897
898 uint alias_idx = C->get_alias_index(adr_type);
899
900 // operate on this memory slice:
901 Node* mem = merge_mem->memory_at(alias_idx); // memory slice to operate on
902
903 // scaling and rounding of indexes:
904 int scale = exact_log2(type2aelembytes(basic_elem_type));
905 int abase = arrayOopDesc::base_offset_in_bytes(basic_elem_type);
906 int clear_low = (-1 << scale) & (BytesPerInt - 1);
907 int bump_bit = (-1 << scale) & BytesPerInt;
908
909 // determine constant starts and ends
910 const intptr_t BIG_NEG = -128;
911 assert(BIG_NEG + 2*abase < 0, "neg enough");
912 intptr_t slice_idx_con = (intptr_t) _igvn.find_int_con(slice_idx, BIG_NEG);
913 intptr_t slice_len_con = (intptr_t) _igvn.find_int_con(slice_len, BIG_NEG);
914 if (slice_len_con == 0) {
915 return; // nothing to do here
916 }
917 intptr_t start_con = (abase + (slice_idx_con << scale)) & ~clear_low;
918 intptr_t end_con = _igvn.find_intptr_t_con(dest_size, -1);
919 if (slice_idx_con >= 0 && slice_len_con >= 0) {
920 assert(end_con < 0, "not two cons");
921 end_con = align_up(abase + ((slice_idx_con + slice_len_con) << scale),
922 BytesPerLong);
923 }
924
925 if (start_con >= 0 && end_con >= 0) {
926 // Constant start and end. Simple.
927 mem = ClearArrayNode::clear_memory(ctrl, mem, dest,
928 start_con, end_con, &_igvn);
929 } else if (start_con >= 0 && dest_size != top()) {
930 // Constant start, pre-rounded end after the tail of the array.
931 Node* end = dest_size;
932 mem = ClearArrayNode::clear_memory(ctrl, mem, dest,
933 start_con, end, &_igvn);
934 } else if (start_con >= 0 && slice_len != top()) {
935 // Constant start, non-constant end. End needs rounding up.
936 // End offset = round_up(abase + ((slice_idx_con + slice_len) << scale), 8)
937 intptr_t end_base = abase + (slice_idx_con << scale);
938 int end_round = (-1 << scale) & (BytesPerLong - 1);
939 Node* end = ConvI2X(slice_len);
940 if (scale != 0)
941 end = transform_later(new LShiftXNode(end, intcon(scale) ));
942 end_base += end_round;
943 end = transform_later(new AddXNode(end, MakeConX(end_base)) );
944 end = transform_later(new AndXNode(end, MakeConX(~end_round)) );
945 mem = ClearArrayNode::clear_memory(ctrl, mem, dest,
946 start_con, end, &_igvn);
947 } else if (start_con < 0 && dest_size != top()) {
948 // Non-constant start, pre-rounded end after the tail of the array.
949 // This is almost certainly a "round-to-end" operation.
950 Node* start = slice_idx;
951 start = ConvI2X(start);
952 if (scale != 0)
953 start = transform_later(new LShiftXNode( start, intcon(scale) ));
954 start = transform_later(new AddXNode(start, MakeConX(abase)) );
955 if ((bump_bit | clear_low) != 0) {
956 int to_clear = (bump_bit | clear_low);
957 // Align up mod 8, then store a jint zero unconditionally
958 // just before the mod-8 boundary.
959 if (((abase + bump_bit) & ~to_clear) - bump_bit
960 < arrayOopDesc::length_offset_in_bytes() + BytesPerInt) {
961 bump_bit = 0;
962 assert((abase & to_clear) == 0, "array base must be long-aligned");
963 } else {
964 // Bump 'start' up to (or past) the next jint boundary:
965 start = transform_later( new AddXNode(start, MakeConX(bump_bit)) );
966 assert((abase & clear_low) == 0, "array base must be int-aligned");
967 }
968 // Round bumped 'start' down to jlong boundary in body of array.
969 start = transform_later(new AndXNode(start, MakeConX(~to_clear)) );
970 if (bump_bit != 0) {
971 // Store a zero to the immediately preceding jint:
972 Node* x1 = transform_later(new AddXNode(start, MakeConX(-bump_bit)) );
973 Node* p1 = basic_plus_adr(dest, x1);
974 mem = StoreNode::make(_igvn, ctrl, mem, p1, adr_type, intcon(0), T_INT, MemNode::unordered);
975 mem = transform_later(mem);
976 }
977 }
978 Node* end = dest_size; // pre-rounded
979 mem = ClearArrayNode::clear_memory(ctrl, mem, dest,
980 start, end, &_igvn);
981 } else {
982 // Non-constant start, unrounded non-constant end.
983 // (Nobody zeroes a random midsection of an array using this routine.)
984 ShouldNotReachHere(); // fix caller
985 }
986
987 // Done.
988 merge_mem->set_memory_at(alias_idx, mem);
989 }
990
991 bool PhaseMacroExpand::generate_block_arraycopy(Node** ctrl, MergeMemNode** mem, Node* io,
992 const TypePtr* adr_type,
993 BasicType basic_elem_type,
994 AllocateNode* alloc,
995 Node* src, Node* src_offset,
996 Node* dest, Node* dest_offset,
997 Node* dest_size, bool dest_uninitialized) {
998 // See if there is an advantage from block transfer.
999 int scale = exact_log2(type2aelembytes(basic_elem_type));
1000 if (scale >= LogBytesPerLong)
1001 return false; // it is already a block transfer
1002
1003 // Look at the alignment of the starting offsets.
1004 int abase = arrayOopDesc::base_offset_in_bytes(basic_elem_type);
1005
1006 intptr_t src_off_con = (intptr_t) _igvn.find_int_con(src_offset, -1);
1007 intptr_t dest_off_con = (intptr_t) _igvn.find_int_con(dest_offset, -1);
1008 if (src_off_con < 0 || dest_off_con < 0) {
1009 // At present, we can only understand constants.
1010 return false;
1011 }
1012
1013 intptr_t src_off = abase + (src_off_con << scale);
1014 intptr_t dest_off = abase + (dest_off_con << scale);
1015
1016 if (((src_off | dest_off) & (BytesPerLong-1)) != 0) {
1017 // Non-aligned; too bad.
1018 // One more chance: Pick off an initial 32-bit word.
1019 // This is a common case, since abase can be odd mod 8.
1020 if (((src_off | dest_off) & (BytesPerLong-1)) == BytesPerInt &&
1021 ((src_off ^ dest_off) & (BytesPerLong-1)) == 0) {
1022 Node* sptr = basic_plus_adr(src, src_off);
1023 Node* dptr = basic_plus_adr(dest, dest_off);
1024 const TypePtr* s_adr_type = _igvn.type(sptr)->is_ptr();
1025 assert(s_adr_type->isa_aryptr(), "impossible slice");
1026 uint s_alias_idx = C->get_alias_index(s_adr_type);
1027 uint d_alias_idx = C->get_alias_index(adr_type);
1028 bool is_mismatched = (basic_elem_type != T_INT);
1029 Node* sval = transform_later(
1030 LoadNode::make(_igvn, *ctrl, (*mem)->memory_at(s_alias_idx), sptr, s_adr_type,
1031 TypeInt::INT, T_INT, MemNode::unordered, LoadNode::DependsOnlyOnTest,
1032 false /*require_atomic_access*/, false /*unaligned*/, is_mismatched));
1033 Node* st = transform_later(
1034 StoreNode::make(_igvn, *ctrl, (*mem)->memory_at(d_alias_idx), dptr, adr_type,
1035 sval, T_INT, MemNode::unordered));
1036 if (is_mismatched) {
1037 st->as_Store()->set_mismatched_access();
1038 }
1039 (*mem)->set_memory_at(d_alias_idx, st);
1040 src_off += BytesPerInt;
1041 dest_off += BytesPerInt;
1042 } else {
1043 return false;
1044 }
1045 }
1046 assert(src_off % BytesPerLong == 0, "");
1047 assert(dest_off % BytesPerLong == 0, "");
1048
1049 // Do this copy by giant steps.
1050 Node* sptr = basic_plus_adr(src, src_off);
1051 Node* dptr = basic_plus_adr(dest, dest_off);
1052 Node* countx = dest_size;
1053 countx = transform_later(new SubXNode(countx, MakeConX(dest_off)));
1054 countx = transform_later(new URShiftXNode(countx, intcon(LogBytesPerLong)));
1055
1056 bool disjoint_bases = true; // since alloc isn't null
1057 generate_unchecked_arraycopy(ctrl, mem,
1058 adr_type, T_LONG, disjoint_bases,
1059 sptr, nullptr, dptr, nullptr, countx, dest_uninitialized);
1060
1061 return true;
1062 }
1063
1064 // Helper function; generates code for the slow case.
1065 // We make a call to a runtime method which emulates the native method,
1066 // but without the native wrapper overhead.
1067 MergeMemNode* PhaseMacroExpand::generate_slow_arraycopy(ArrayCopyNode *ac,
1068 Node** ctrl, Node* mem, Node** io,
1069 const TypePtr* adr_type,
1070 Node* src, Node* src_offset,
1071 Node* dest, Node* dest_offset,
1072 Node* copy_length, bool dest_uninitialized) {
1073 assert(!dest_uninitialized, "Invariant");
1074
1075 const TypeFunc* call_type = OptoRuntime::slow_arraycopy_Type();
1076 CallNode* call = new CallStaticJavaNode(call_type, OptoRuntime::slow_arraycopy_Java(),
1077 "slow_arraycopy", TypePtr::BOTTOM);
1078
1079 call->init_req(TypeFunc::Control, *ctrl);
1080 call->init_req(TypeFunc::I_O , *io);
1081 call->init_req(TypeFunc::Memory , mem);
1082 call->init_req(TypeFunc::ReturnAdr, top());
1083 call->init_req(TypeFunc::FramePtr, top());
1084 call->init_req(TypeFunc::Parms+0, src);
1085 call->init_req(TypeFunc::Parms+1, src_offset);
1086 call->init_req(TypeFunc::Parms+2, dest);
1087 call->init_req(TypeFunc::Parms+3, dest_offset);
1088 call->init_req(TypeFunc::Parms+4, copy_length);
1089 call->copy_call_debug_info(&_igvn, ac);
1090
1091 call->set_cnt(PROB_UNLIKELY_MAG(4)); // Same effect as RC_UNCOMMON.
1092 _igvn.replace_node(ac, call);
1093 transform_later(call);
1094
1095 call->extract_projections(&_callprojs, false /*separate_io_proj*/, false /*do_asserts*/);
1096 *ctrl = _callprojs.fallthrough_catchproj->clone();
1097 transform_later(*ctrl);
1098
1099 Node* m = _callprojs.fallthrough_memproj->clone();
1100 transform_later(m);
1101
1102 uint alias_idx = C->get_alias_index(adr_type);
1103 MergeMemNode* out_mem;
1104 if (alias_idx != Compile::AliasIdxBot) {
1105 out_mem = MergeMemNode::make(mem);
1106 out_mem->set_memory_at(alias_idx, m);
1107 } else {
1108 out_mem = MergeMemNode::make(m);
1109 }
1110 transform_later(out_mem);
1111
1112 // When src is negative and arraycopy is before an infinite loop,_callprojs.fallthrough_ioproj
1113 // could be null. Skip clone and update null fallthrough_ioproj.
1114 if (_callprojs.fallthrough_ioproj != nullptr) {
1115 *io = _callprojs.fallthrough_ioproj->clone();
1116 transform_later(*io);
1117 } else {
1118 *io = nullptr;
1119 }
1120
1121 return out_mem;
1122 }
1123
1124 // Helper function; generates code for cases requiring runtime checks.
1125 Node* PhaseMacroExpand::generate_checkcast_arraycopy(Node** ctrl, MergeMemNode** mem,
1126 const TypePtr* adr_type,
1127 Node* dest_elem_klass,
1128 Node* src, Node* src_offset,
1129 Node* dest, Node* dest_offset,
1130 Node* copy_length, bool dest_uninitialized) {
1131 if ((*ctrl)->is_top()) return nullptr;
1132
1133 address copyfunc_addr = StubRoutines::checkcast_arraycopy(dest_uninitialized);
1134 if (copyfunc_addr == nullptr) { // Stub was not generated, go slow path.
1135 return nullptr;
1136 }
1137
1138 // Pick out the parameters required to perform a store-check
1139 // for the target array. This is an optimistic check. It will
1140 // look in each non-null element's class, at the desired klass's
1141 // super_check_offset, for the desired klass.
1142 int sco_offset = in_bytes(Klass::super_check_offset_offset());
1143 Node* p3 = basic_plus_adr(dest_elem_klass, sco_offset);
1144 Node* n3 = new LoadINode(nullptr, *mem /*memory(p3)*/, p3, _igvn.type(p3)->is_ptr(), TypeInt::INT, MemNode::unordered);
1145 Node* check_offset = ConvI2X(transform_later(n3));
1146 Node* check_value = dest_elem_klass;
1147
1148 Node* src_start = array_element_address(src, src_offset, T_OBJECT);
1149 Node* dest_start = array_element_address(dest, dest_offset, T_OBJECT);
1150
1151 const TypeFunc* call_type = OptoRuntime::checkcast_arraycopy_Type();
1152 Node* call = make_leaf_call(*ctrl, *mem, call_type, copyfunc_addr, "checkcast_arraycopy", adr_type,
1153 src_start, dest_start, copy_length XTOP, check_offset XTOP, check_value);
1154
1155 finish_arraycopy_call(call, ctrl, mem, adr_type);
1156
1157 Node* proj = new ProjNode(call, TypeFunc::Parms);
1158 transform_later(proj);
1159
1160 return proj;
1161 }
1162
1163 // Helper function; generates code for cases requiring runtime checks.
1164 Node* PhaseMacroExpand::generate_generic_arraycopy(Node** ctrl, MergeMemNode** mem,
1165 const TypePtr* adr_type,
1166 Node* src, Node* src_offset,
1167 Node* dest, Node* dest_offset,
1168 Node* copy_length, bool dest_uninitialized) {
1169 if ((*ctrl)->is_top()) return nullptr;
1170 assert(!dest_uninitialized, "Invariant");
1171
1172 address copyfunc_addr = StubRoutines::generic_arraycopy();
1173 if (copyfunc_addr == nullptr) { // Stub was not generated, go slow path.
1174 return nullptr;
1175 }
1176
1177 const TypeFunc* call_type = OptoRuntime::generic_arraycopy_Type();
1178 Node* call = make_leaf_call(*ctrl, *mem, call_type, copyfunc_addr, "generic_arraycopy", adr_type,
1179 src, src_offset, dest, dest_offset, copy_length);
1180
1181 finish_arraycopy_call(call, ctrl, mem, adr_type);
1182
1183 Node* proj = new ProjNode(call, TypeFunc::Parms);
1184 transform_later(proj);
1185
1186 return proj;
1187 }
1188
1189 // Helper function; generates the fast out-of-line call to an arraycopy stub.
1190 void PhaseMacroExpand::generate_unchecked_arraycopy(Node** ctrl, MergeMemNode** mem,
1191 const TypePtr* adr_type,
1192 BasicType basic_elem_type,
1193 bool disjoint_bases,
1194 Node* src, Node* src_offset,
1195 Node* dest, Node* dest_offset,
1196 Node* copy_length, bool dest_uninitialized) {
1197 if ((*ctrl)->is_top()) {
1198 return;
1199 }
1200
1201 Node* src_start = src;
1202 Node* dest_start = dest;
1203 if (src_offset != nullptr || dest_offset != nullptr) {
1204 src_start = array_element_address(src, src_offset, basic_elem_type);
1205 dest_start = array_element_address(dest, dest_offset, basic_elem_type);
1206 }
1207
1208 // Figure out which arraycopy runtime method to call.
1209 const char* copyfunc_name = "arraycopy";
1210 address copyfunc_addr =
1211 basictype2arraycopy(basic_elem_type, src_offset, dest_offset,
1212 disjoint_bases, copyfunc_name, dest_uninitialized);
1213
1214 Node* result_memory = nullptr;
1215 RegionNode* exit_block = nullptr;
1216 if (ArrayOperationPartialInlineSize > 0 && is_subword_type(basic_elem_type) &&
1217 Matcher::vector_width_in_bytes(basic_elem_type) >= 16) {
1218 generate_partial_inlining_block(ctrl, mem, adr_type, &exit_block, &result_memory,
1219 copy_length, src_start, dest_start, basic_elem_type);
1220 }
1221
1222 const TypeFunc* call_type = OptoRuntime::fast_arraycopy_Type();
1223 Node* call = make_leaf_call(*ctrl, *mem, call_type, copyfunc_addr, copyfunc_name, adr_type,
1224 src_start, dest_start, copy_length XTOP);
1225
1226 finish_arraycopy_call(call, ctrl, mem, adr_type);
1227
1228 // Connecting remaining edges for exit_block coming from stub_block.
1229 if (exit_block) {
1230 exit_block->init_req(2, *ctrl);
1231
1232 // Memory edge corresponding to stub_region.
1233 result_memory->init_req(2, *mem);
1234
1235 uint alias_idx = C->get_alias_index(adr_type);
1236 if (alias_idx != Compile::AliasIdxBot) {
1237 *mem = MergeMemNode::make(*mem);
1238 (*mem)->set_memory_at(alias_idx, result_memory);
1239 } else {
1240 *mem = MergeMemNode::make(result_memory);
1241 }
1242 transform_later(*mem);
1243 *ctrl = exit_block;
1244 }
1245 }
1246
1247 #undef XTOP
1248
1249 void PhaseMacroExpand::expand_arraycopy_node(ArrayCopyNode *ac) {
1250 Node* ctrl = ac->in(TypeFunc::Control);
1251 Node* io = ac->in(TypeFunc::I_O);
1252 Node* src = ac->in(ArrayCopyNode::Src);
1253 Node* src_offset = ac->in(ArrayCopyNode::SrcPos);
1254 Node* dest = ac->in(ArrayCopyNode::Dest);
1255 Node* dest_offset = ac->in(ArrayCopyNode::DestPos);
1256 Node* length = ac->in(ArrayCopyNode::Length);
1257 MergeMemNode* merge_mem = nullptr;
1258
1259 if (ac->is_clonebasic()) {
1260 BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2();
1261 bs->clone_at_expansion(this, ac);
1262 return;
1263 } else if (ac->is_copyof() || ac->is_copyofrange() || ac->is_clone_oop_array()) {
1264 Node* mem = ac->in(TypeFunc::Memory);
1265 merge_mem = MergeMemNode::make(mem);
1266 transform_later(merge_mem);
1267
1268 AllocateArrayNode* alloc = nullptr;
1269 if (ac->is_alloc_tightly_coupled()) {
1270 alloc = AllocateArrayNode::Ideal_array_allocation(dest);
1271 assert(alloc != nullptr, "expect alloc");
1272 }
1273
1274 const TypePtr* adr_type = _igvn.type(dest)->is_oopptr()->add_offset(Type::OffsetBot);
1275 if (ac->_dest_type != TypeOopPtr::BOTTOM) {
1276 adr_type = ac->_dest_type->add_offset(Type::OffsetBot)->is_ptr();
1277 }
1278 generate_arraycopy(ac, alloc, &ctrl, merge_mem, &io,
1279 adr_type, T_OBJECT,
1280 src, src_offset, dest, dest_offset, length,
1281 true, ac->has_negative_length_guard());
1282
1283 return;
1284 }
1285
1286 AllocateArrayNode* alloc = nullptr;
1287 if (ac->is_alloc_tightly_coupled()) {
1288 alloc = AllocateArrayNode::Ideal_array_allocation(dest);
1289 assert(alloc != nullptr, "expect alloc");
1290 }
1291
1292 assert(ac->is_arraycopy() || ac->is_arraycopy_validated(), "should be an arraycopy");
1293
1294 // Compile time checks. If any of these checks cannot be verified at compile time,
1295 // we do not make a fast path for this call. Instead, we let the call remain as it
1296 // is. The checks we choose to mandate at compile time are:
1297 //
1298 // (1) src and dest are arrays.
1299 const Type* src_type = src->Value(&_igvn);
1300 const Type* dest_type = dest->Value(&_igvn);
1301 const TypeAryPtr* top_src = src_type->isa_aryptr();
1302 const TypeAryPtr* top_dest = dest_type->isa_aryptr();
1303
1304 BasicType src_elem = T_CONFLICT;
1305 BasicType dest_elem = T_CONFLICT;
1306
1307 if (top_src != nullptr && top_src->elem() != Type::BOTTOM) {
1308 src_elem = top_src->elem()->array_element_basic_type();
1309 }
1310 if (top_dest != nullptr && top_dest->elem() != Type::BOTTOM) {
1311 dest_elem = top_dest->elem()->array_element_basic_type();
1312 }
1313 if (is_reference_type(src_elem, true)) src_elem = T_OBJECT;
1314 if (is_reference_type(dest_elem, true)) dest_elem = T_OBJECT;
1315
1316 if (ac->is_arraycopy_validated() &&
1317 dest_elem != T_CONFLICT &&
1318 src_elem == T_CONFLICT) {
1319 src_elem = dest_elem;
1320 }
1321
1322 if (src_elem == T_CONFLICT || dest_elem == T_CONFLICT) {
1323 // Conservatively insert a memory barrier on all memory slices.
1324 // Do not let writes into the source float below the arraycopy.
1325 {
1326 Node* mem = ac->in(TypeFunc::Memory);
1327 insert_mem_bar(&ctrl, &mem, Op_MemBarCPUOrder, Compile::AliasIdxBot);
1328
1329 merge_mem = MergeMemNode::make(mem);
1330 transform_later(merge_mem);
1331 }
1332
1333 // Call StubRoutines::generic_arraycopy stub.
1334 Node* mem = generate_arraycopy(ac, nullptr, &ctrl, merge_mem, &io,
1335 TypeRawPtr::BOTTOM, T_CONFLICT,
1336 src, src_offset, dest, dest_offset, length,
1337 // If a negative length guard was generated for the ArrayCopyNode,
1338 // the length of the array can never be negative.
1339 false, ac->has_negative_length_guard());
1340 return;
1341 }
1342
1343 assert(!ac->is_arraycopy_validated() || (src_elem == dest_elem && dest_elem != T_VOID), "validated but different basic types");
1344
1345 // (2) src and dest arrays must have elements of the same BasicType
1346 // Figure out the size and type of the elements we will be copying.
1347 if (src_elem != dest_elem || dest_elem == T_VOID) {
1348 // The component types are not the same or are not recognized. Punt.
1349 // (But, avoid the native method wrapper to JVM_ArrayCopy.)
1350 {
1351 Node* mem = ac->in(TypeFunc::Memory);
1352 merge_mem = generate_slow_arraycopy(ac, &ctrl, mem, &io, TypePtr::BOTTOM, src, src_offset, dest, dest_offset, length, false);
1353 }
1354
1355 _igvn.replace_node(_callprojs.fallthrough_memproj, merge_mem);
1356 if (_callprojs.fallthrough_ioproj != nullptr) {
1357 _igvn.replace_node(_callprojs.fallthrough_ioproj, io);
1358 }
1359 _igvn.replace_node(_callprojs.fallthrough_catchproj, ctrl);
1360 return;
1361 }
1362
1363 //---------------------------------------------------------------------------
1364 // We will make a fast path for this call to arraycopy.
1365
1366 // We have the following tests left to perform:
1367 //
1368 // (3) src and dest must not be null.
1369 // (4) src_offset must not be negative.
1370 // (5) dest_offset must not be negative.
1371 // (6) length must not be negative.
1372 // (7) src_offset + length must not exceed length of src.
1373 // (8) dest_offset + length must not exceed length of dest.
1374 // (9) each element of an oop array must be assignable
1375
1376 {
1377 Node* mem = ac->in(TypeFunc::Memory);
1378 merge_mem = MergeMemNode::make(mem);
1379 transform_later(merge_mem);
1380 }
1381
1382 RegionNode* slow_region = new RegionNode(1);
1383 transform_later(slow_region);
1384
1385 if (!ac->is_arraycopy_validated()) {
1386 // (3) operands must not be null
1387 // We currently perform our null checks with the null_check routine.
1388 // This means that the null exceptions will be reported in the caller
1389 // rather than (correctly) reported inside of the native arraycopy call.
1390 // This should be corrected, given time. We do our null check with the
1391 // stack pointer restored.
1392 // null checks done library_call.cpp
1393
1394 // (4) src_offset must not be negative.
1395 generate_negative_guard(&ctrl, src_offset, slow_region);
1396
1397 // (5) dest_offset must not be negative.
1398 generate_negative_guard(&ctrl, dest_offset, slow_region);
1399
1400 // (6) length must not be negative (moved to generate_arraycopy()).
1401 // generate_negative_guard(length, slow_region);
1402
1403 // (7) src_offset + length must not exceed length of src.
1404 Node* alen = ac->in(ArrayCopyNode::SrcLen);
1405 assert(alen != nullptr, "need src len");
1406 generate_limit_guard(&ctrl,
1407 src_offset, length,
1408 alen,
1409 slow_region);
1410
1411 // (8) dest_offset + length must not exceed length of dest.
1412 alen = ac->in(ArrayCopyNode::DestLen);
1413 assert(alen != nullptr, "need dest len");
1414 generate_limit_guard(&ctrl,
1415 dest_offset, length,
1416 alen,
1417 slow_region);
1418
1419 // (9) each element of an oop array must be assignable
1420 // The generate_arraycopy subroutine checks this.
1421 }
1422 // This is where the memory effects are placed:
1423 const TypePtr* adr_type = nullptr;
1424 if (ac->_dest_type != TypeOopPtr::BOTTOM) {
1425 adr_type = ac->_dest_type->add_offset(Type::OffsetBot)->is_ptr();
1426 } else {
1427 adr_type = TypeAryPtr::get_array_body_type(dest_elem);
1428 }
1429
1430 generate_arraycopy(ac, alloc, &ctrl, merge_mem, &io,
1431 adr_type, dest_elem,
1432 src, src_offset, dest, dest_offset, length,
1433 // If a negative length guard was generated for the ArrayCopyNode,
1434 // the length of the array can never be negative.
1435 false, ac->has_negative_length_guard(), slow_region);
1436 }