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