parse3.cpp revision 3718:b9a9ed0f8eeb
1282785Sgjb/* 2282785Sgjb * Copyright (c) 1998, 2012, Oracle and/or its affiliates. All rights reserved. 3282785Sgjb * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4282785Sgjb * 5282785Sgjb * This code is free software; you can redistribute it and/or modify it 6282785Sgjb * under the terms of the GNU General Public License version 2 only, as 7282785Sgjb * published by the Free Software Foundation. 8282798Sgjb * 9282798Sgjb * This code is distributed in the hope that it will be useful, but WITHOUT 10282798Sgjb * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11282798Sgjb * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12282785Sgjb * version 2 for more details (a copy is included in the LICENSE file that 13282785Sgjb * accompanied this code). 14282785Sgjb * 15282785Sgjb * You should have received a copy of the GNU General Public License version 16282785Sgjb * 2 along with this work; if not, write to the Free Software Foundation, 17282787Sgjb * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18282799Sgjb * 19282785Sgjb * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20282785Sgjb * or visit www.oracle.com if you need additional information or have any 21283271Sgjb * questions. 22283271Sgjb * 23283271Sgjb */ 24283271Sgjb 25282785Sgjb#include "precompiled.hpp" 26282785Sgjb#include "compiler/compileLog.hpp" 27282785Sgjb#include "interpreter/linkResolver.hpp" 28282785Sgjb#include "memory/universe.inline.hpp" 29282785Sgjb#include "oops/objArrayKlass.hpp" 30282785Sgjb#include "opto/addnode.hpp" 31282785Sgjb#include "opto/memnode.hpp" 32282785Sgjb#include "opto/parse.hpp" 33282785Sgjb#include "opto/rootnode.hpp" 34282785Sgjb#include "opto/runtime.hpp" 35282785Sgjb#include "opto/subnode.hpp" 36283271Sgjb#include "runtime/deoptimization.hpp" 37283271Sgjb#include "runtime/handles.inline.hpp" 38283271Sgjb 39283271Sgjb//============================================================================= 40283271Sgjb// Helper methods for _get* and _put* bytecodes 41282785Sgjb//============================================================================= 42282785Sgjbbool Parse::static_field_ok_in_clinit(ciField *field, ciMethod *method) { 43283271Sgjb // Could be the field_holder's <clinit> method, or <clinit> for a subklass. 44283271Sgjb // Better to check now than to Deoptimize as soon as we execute 45283271Sgjb assert( field->is_static(), "Only check if field is static"); 46282785Sgjb // is_being_initialized() is too generous. It allows access to statics 47282785Sgjb // by threads that are not running the <clinit> before the <clinit> finishes. 48282785Sgjb // return field->holder()->is_being_initialized(); 49282785Sgjb 50282785Sgjb // The following restriction is correct but conservative. 51282785Sgjb // It is also desirable to allow compilation of methods called from <clinit> 52282785Sgjb // but this generated code will need to be made safe for execution by 53283271Sgjb // other threads, or the transition from interpreted to compiled code would 54283271Sgjb // need to be guarded. 55283271Sgjb ciInstanceKlass *field_holder = field->holder(); 56283271Sgjb 57283271Sgjb bool access_OK = false; 58283271Sgjb if (method->holder()->is_subclass_of(field_holder)) { 59283271Sgjb if (method->is_static()) { 60283271Sgjb if (method->name() == ciSymbol::class_initializer_name()) { 61283271Sgjb // OK to access static fields inside initializer 62283271Sgjb access_OK = true; 63283271Sgjb } 64283271Sgjb } else { 65283271Sgjb if (method->name() == ciSymbol::object_initializer_name()) { 66283271Sgjb // It's also OK to access static fields inside a constructor, 67282785Sgjb // because any thread calling the constructor must first have 68282785Sgjb // synchronized on the class by executing a '_new' bytecode. 69282785Sgjb access_OK = true; 70282785Sgjb } 71282785Sgjb } 72282785Sgjb } 73282785Sgjb 74282785Sgjb return access_OK; 75282785Sgjb 76282785Sgjb} 77282785Sgjb 78282789Sgjb 79282789Sgjbvoid Parse::do_field_access(bool is_get, bool is_field) { 80282789Sgjb bool will_link; 81282785Sgjb ciField* field = iter().get_field(will_link); 82282785Sgjb assert(will_link, "getfield: typeflow responsibility"); 83282785Sgjb 84282787Sgjb ciInstanceKlass* field_holder = field->holder(); 85282787Sgjb 86282787Sgjb if (is_field == field->is_static()) { 87283271Sgjb // Interpreter will throw java_lang_IncompatibleClassChangeError 88283271Sgjb // Check this before allowing <clinit> methods to access static fields 89283271Sgjb uncommon_trap(Deoptimization::Reason_unhandled, 90283271Sgjb Deoptimization::Action_none); 91283271Sgjb return; 92283271Sgjb } 93282787Sgjb 94282787Sgjb if (!is_field && !field_holder->is_initialized()) { 95283271Sgjb if (!static_field_ok_in_clinit(field, method())) { 96283271Sgjb uncommon_trap(Deoptimization::Reason_uninitialized, 97282792Sgjb Deoptimization::Action_reinterpret, 98282787Sgjb NULL, "!static_field_ok_in_clinit"); 99283271Sgjb return; 100282793Sgjb } 101282793Sgjb } 102282793Sgjb 103282793Sgjb // Deoptimize on putfield writes to call site target field. 104282791Sgjb if (!is_get && field->is_call_site_target()) { 105282787Sgjb uncommon_trap(Deoptimization::Reason_unhandled, 106282787Sgjb Deoptimization::Action_reinterpret, 107282785Sgjb NULL, "put to call site target field"); 108282785Sgjb return; 109282785Sgjb } 110283271Sgjb 111283265Sgjb assert(field->will_link(method()->holder(), bc()), "getfield: typeflow responsibility"); 112283271Sgjb 113282785Sgjb // Note: We do not check for an unloaded field type here any more. 114282785Sgjb 115283271Sgjb // Generate code for the object pointer. 116283265Sgjb Node* obj; 117283265Sgjb if (is_field) { 118283271Sgjb int obj_depth = is_get ? 0 : field->type()->size(); 119283271Sgjb obj = do_null_check(peek(obj_depth), T_OBJECT); 120282785Sgjb // Compile-time detect of null-exception? 121282785Sgjb if (stopped()) return; 122282785Sgjb 123282785Sgjb#ifdef ASSERT 124282785Sgjb const TypeInstPtr *tjp = TypeInstPtr::make(TypePtr::NotNull, iter().get_declared_field_holder()); 125283271Sgjb assert(_gvn.type(obj)->higher_equal(tjp), "cast_up is no longer needed"); 126282785Sgjb#endif 127283271Sgjb 128283271Sgjb if (is_get) { 129283271Sgjb --_sp; // pop receiver before getting 130283271Sgjb do_get_xxx(obj, field, is_field); 131283271Sgjb } else { 132283271Sgjb do_put_xxx(obj, field, is_field); 133283265Sgjb --_sp; // pop receiver after putting 134282796Sgjb } 135282794Sgjb } else { 136283265Sgjb const TypeInstPtr* tip = TypeInstPtr::make(field_holder->java_mirror()); 137283271Sgjb obj = _gvn.makecon(tip); 138282785Sgjb if (is_get) { 139282785Sgjb do_get_xxx(obj, field, is_field); 140282785Sgjb } else { 141283271Sgjb do_put_xxx(obj, field, is_field); 142283266Sgjb } 143283271Sgjb } 144282785Sgjb} 145283266Sgjb 146282785Sgjb 147282787Sgjbvoid Parse::do_get_xxx(Node* obj, ciField* field, bool is_field) { 148282785Sgjb // Does this field have a constant value? If so, just push the value. 149282787Sgjb if (field->is_constant()) { 150282785Sgjb // final field 151282785Sgjb if (field->is_static()) { 152282785Sgjb // final static field 153282785Sgjb if (push_constant(field->constant_value())) 154282785Sgjb return; 155282785Sgjb } 156282785Sgjb else { 157282785Sgjb // final non-static field 158282785Sgjb // Treat final non-static fields of trusted classes (classes in 159282785Sgjb // java.lang.invoke and sun.invoke packages and subpackages) as 160282785Sgjb // compile time constants. 161282785Sgjb if (obj->is_Con()) { 162282785Sgjb const TypeOopPtr* oop_ptr = obj->bottom_type()->isa_oopptr(); 163282785Sgjb ciObject* constant_oop = oop_ptr->const_oop(); 164282785Sgjb ciConstant constant = field->constant_value_of(constant_oop); 165282785Sgjb if (push_constant(constant, true)) 166282785Sgjb return; 167282785Sgjb } 168282785Sgjb } 169282785Sgjb } 170282785Sgjb 171282785Sgjb ciType* field_klass = field->type(); 172282785Sgjb bool is_vol = field->is_volatile(); 173282785Sgjb 174282785Sgjb // Compute address and memory type. 175282785Sgjb int offset = field->offset_in_bytes(); 176282785Sgjb const TypePtr* adr_type = C->alias_type(field)->adr_type(); 177282785Sgjb Node *adr = basic_plus_adr(obj, obj, offset); 178282785Sgjb BasicType bt = field->layout_type(); 179282785Sgjb 180282785Sgjb // Build the resultant type of the load 181282785Sgjb const Type *type; 182282785Sgjb 183282785Sgjb bool must_assert_null = false; 184282785Sgjb 185282785Sgjb if( bt == T_OBJECT ) { 186282785Sgjb if (!field->type()->is_loaded()) { 187282789Sgjb type = TypeInstPtr::BOTTOM; 188282785Sgjb must_assert_null = true; 189 } else if (field->is_constant() && field->is_static()) { 190 // This can happen if the constant oop is non-perm. 191 ciObject* con = field->constant_value().as_object(); 192 // Do not "join" in the previous type; it doesn't add value, 193 // and may yield a vacuous result if the field is of interface type. 194 type = TypeOopPtr::make_from_constant(con)->isa_oopptr(); 195 assert(type != NULL, "field singleton type must be consistent"); 196 } else { 197 type = TypeOopPtr::make_from_klass(field_klass->as_klass()); 198 } 199 } else { 200 type = Type::get_const_basic_type(bt); 201 } 202 // Build the load. 203 Node* ld = make_load(NULL, adr, type, bt, adr_type, is_vol); 204 205 // Adjust Java stack 206 if (type2size[bt] == 1) 207 push(ld); 208 else 209 push_pair(ld); 210 211 if (must_assert_null) { 212 // Do not take a trap here. It's possible that the program 213 // will never load the field's class, and will happily see 214 // null values in this field forever. Don't stumble into a 215 // trap for such a program, or we might get a long series 216 // of useless recompilations. (Or, we might load a class 217 // which should not be loaded.) If we ever see a non-null 218 // value, we will then trap and recompile. (The trap will 219 // not need to mention the class index, since the class will 220 // already have been loaded if we ever see a non-null value.) 221 // uncommon_trap(iter().get_field_signature_index()); 222#ifndef PRODUCT 223 if (PrintOpto && (Verbose || WizardMode)) { 224 method()->print_name(); tty->print_cr(" asserting nullness of field at bci: %d", bci()); 225 } 226#endif 227 if (C->log() != NULL) { 228 C->log()->elem("assert_null reason='field' klass='%d'", 229 C->log()->identify(field->type())); 230 } 231 // If there is going to be a trap, put it at the next bytecode: 232 set_bci(iter().next_bci()); 233 do_null_assert(peek(), T_OBJECT); 234 set_bci(iter().cur_bci()); // put it back 235 } 236 237 // If reference is volatile, prevent following memory ops from 238 // floating up past the volatile read. Also prevents commoning 239 // another volatile read. 240 if (field->is_volatile()) { 241 // Memory barrier includes bogus read of value to force load BEFORE membar 242 insert_mem_bar(Op_MemBarAcquire, ld); 243 } 244} 245 246void Parse::do_put_xxx(Node* obj, ciField* field, bool is_field) { 247 bool is_vol = field->is_volatile(); 248 // If reference is volatile, prevent following memory ops from 249 // floating down past the volatile write. Also prevents commoning 250 // another volatile read. 251 if (is_vol) insert_mem_bar(Op_MemBarRelease); 252 253 // Compute address and memory type. 254 int offset = field->offset_in_bytes(); 255 const TypePtr* adr_type = C->alias_type(field)->adr_type(); 256 Node* adr = basic_plus_adr(obj, obj, offset); 257 BasicType bt = field->layout_type(); 258 // Value to be stored 259 Node* val = type2size[bt] == 1 ? pop() : pop_pair(); 260 // Round doubles before storing 261 if (bt == T_DOUBLE) val = dstore_rounding(val); 262 263 // Store the value. 264 Node* store; 265 if (bt == T_OBJECT) { 266 const TypeOopPtr* field_type; 267 if (!field->type()->is_loaded()) { 268 field_type = TypeInstPtr::BOTTOM; 269 } else { 270 field_type = TypeOopPtr::make_from_klass(field->type()->as_klass()); 271 } 272 store = store_oop_to_object( control(), obj, adr, adr_type, val, field_type, bt); 273 } else { 274 store = store_to_memory( control(), adr, val, bt, adr_type, is_vol ); 275 } 276 277 // If reference is volatile, prevent following volatiles ops from 278 // floating up before the volatile write. 279 if (is_vol) { 280 // First place the specific membar for THIS volatile index. This first 281 // membar is dependent on the store, keeping any other membars generated 282 // below from floating up past the store. 283 int adr_idx = C->get_alias_index(adr_type); 284 insert_mem_bar_volatile(Op_MemBarVolatile, adr_idx, store); 285 286 // Now place a membar for AliasIdxBot for the unknown yet-to-be-parsed 287 // volatile alias indices. Skip this if the membar is redundant. 288 if (adr_idx != Compile::AliasIdxBot) { 289 insert_mem_bar_volatile(Op_MemBarVolatile, Compile::AliasIdxBot, store); 290 } 291 292 // Finally, place alias-index-specific membars for each volatile index 293 // that isn't the adr_idx membar. Typically there's only 1 or 2. 294 for( int i = Compile::AliasIdxRaw; i < C->num_alias_types(); i++ ) { 295 if (i != adr_idx && C->alias_type(i)->is_volatile()) { 296 insert_mem_bar_volatile(Op_MemBarVolatile, i, store); 297 } 298 } 299 } 300 301 // If the field is final, the rules of Java say we are in <init> or <clinit>. 302 // Note the presence of writes to final non-static fields, so that we 303 // can insert a memory barrier later on to keep the writes from floating 304 // out of the constructor. 305 if (is_field && field->is_final()) { 306 set_wrote_final(true); 307 } 308} 309 310 311bool Parse::push_constant(ciConstant constant, bool require_constant) { 312 switch (constant.basic_type()) { 313 case T_BOOLEAN: push( intcon(constant.as_boolean()) ); break; 314 case T_INT: push( intcon(constant.as_int()) ); break; 315 case T_CHAR: push( intcon(constant.as_char()) ); break; 316 case T_BYTE: push( intcon(constant.as_byte()) ); break; 317 case T_SHORT: push( intcon(constant.as_short()) ); break; 318 case T_FLOAT: push( makecon(TypeF::make(constant.as_float())) ); break; 319 case T_DOUBLE: push_pair( makecon(TypeD::make(constant.as_double())) ); break; 320 case T_LONG: push_pair( longcon(constant.as_long()) ); break; 321 case T_ARRAY: 322 case T_OBJECT: { 323 // cases: 324 // can_be_constant = (oop not scavengable || ScavengeRootsInCode != 0) 325 // should_be_constant = (oop not scavengable || ScavengeRootsInCode >= 2) 326 // An oop is not scavengable if it is in the perm gen. 327 ciObject* oop_constant = constant.as_object(); 328 if (oop_constant->is_null_object()) { 329 push( zerocon(T_OBJECT) ); 330 break; 331 } else if (require_constant || oop_constant->should_be_constant()) { 332 push( makecon(TypeOopPtr::make_from_constant(oop_constant, require_constant)) ); 333 break; 334 } else { 335 // we cannot inline the oop, but we can use it later to narrow a type 336 return false; 337 } 338 } 339 case T_ILLEGAL: { 340 // Invalid ciConstant returned due to OutOfMemoryError in the CI 341 assert(C->env()->failing(), "otherwise should not see this"); 342 // These always occur because of object types; we are going to 343 // bail out anyway, so make the stack depths match up 344 push( zerocon(T_OBJECT) ); 345 return false; 346 } 347 default: 348 ShouldNotReachHere(); 349 return false; 350 } 351 352 // success 353 return true; 354} 355 356 357 358//============================================================================= 359void Parse::do_anewarray() { 360 bool will_link; 361 ciKlass* klass = iter().get_klass(will_link); 362 363 // Uncommon Trap when class that array contains is not loaded 364 // we need the loaded class for the rest of graph; do not 365 // initialize the container class (see Java spec)!!! 366 assert(will_link, "anewarray: typeflow responsibility"); 367 368 ciObjArrayKlass* array_klass = ciObjArrayKlass::make(klass); 369 // Check that array_klass object is loaded 370 if (!array_klass->is_loaded()) { 371 // Generate uncommon_trap for unloaded array_class 372 uncommon_trap(Deoptimization::Reason_unloaded, 373 Deoptimization::Action_reinterpret, 374 array_klass); 375 return; 376 } 377 378 kill_dead_locals(); 379 380 const TypeKlassPtr* array_klass_type = TypeKlassPtr::make(array_klass); 381 Node* count_val = pop(); 382 Node* obj = new_array(makecon(array_klass_type), count_val, 1); 383 push(obj); 384} 385 386 387void Parse::do_newarray(BasicType elem_type) { 388 kill_dead_locals(); 389 390 Node* count_val = pop(); 391 const TypeKlassPtr* array_klass = TypeKlassPtr::make(ciTypeArrayKlass::make(elem_type)); 392 Node* obj = new_array(makecon(array_klass), count_val, 1); 393 // Push resultant oop onto stack 394 push(obj); 395} 396 397// Expand simple expressions like new int[3][5] and new Object[2][nonConLen]. 398// Also handle the degenerate 1-dimensional case of anewarray. 399Node* Parse::expand_multianewarray(ciArrayKlass* array_klass, Node* *lengths, int ndimensions, int nargs) { 400 Node* length = lengths[0]; 401 assert(length != NULL, ""); 402 Node* array = new_array(makecon(TypeKlassPtr::make(array_klass)), length, nargs); 403 if (ndimensions > 1) { 404 jint length_con = find_int_con(length, -1); 405 guarantee(length_con >= 0, "non-constant multianewarray"); 406 ciArrayKlass* array_klass_1 = array_klass->as_obj_array_klass()->element_klass()->as_array_klass(); 407 const TypePtr* adr_type = TypeAryPtr::OOPS; 408 const TypeOopPtr* elemtype = _gvn.type(array)->is_aryptr()->elem()->make_oopptr(); 409 const intptr_t header = arrayOopDesc::base_offset_in_bytes(T_OBJECT); 410 for (jint i = 0; i < length_con; i++) { 411 Node* elem = expand_multianewarray(array_klass_1, &lengths[1], ndimensions-1, nargs); 412 intptr_t offset = header + ((intptr_t)i << LogBytesPerHeapOop); 413 Node* eaddr = basic_plus_adr(array, offset); 414 store_oop_to_array(control(), array, eaddr, adr_type, elem, elemtype, T_OBJECT); 415 } 416 } 417 return array; 418} 419 420void Parse::do_multianewarray() { 421 int ndimensions = iter().get_dimensions(); 422 423 // the m-dimensional array 424 bool will_link; 425 ciArrayKlass* array_klass = iter().get_klass(will_link)->as_array_klass(); 426 assert(will_link, "multianewarray: typeflow responsibility"); 427 428 // Note: Array classes are always initialized; no is_initialized check. 429 430 kill_dead_locals(); 431 432 // get the lengths from the stack (first dimension is on top) 433 Node** length = NEW_RESOURCE_ARRAY(Node*, ndimensions + 1); 434 length[ndimensions] = NULL; // terminating null for make_runtime_call 435 int j; 436 for (j = ndimensions-1; j >= 0 ; j--) length[j] = pop(); 437 438 // The original expression was of this form: new T[length0][length1]... 439 // It is often the case that the lengths are small (except the last). 440 // If that happens, use the fast 1-d creator a constant number of times. 441 const jint expand_limit = MIN2((juint)MultiArrayExpandLimit, (juint)100); 442 jint expand_count = 1; // count of allocations in the expansion 443 jint expand_fanout = 1; // running total fanout 444 for (j = 0; j < ndimensions-1; j++) { 445 jint dim_con = find_int_con(length[j], -1); 446 expand_fanout *= dim_con; 447 expand_count += expand_fanout; // count the level-J sub-arrays 448 if (dim_con <= 0 449 || dim_con > expand_limit 450 || expand_count > expand_limit) { 451 expand_count = 0; 452 break; 453 } 454 } 455 456 // Can use multianewarray instead of [a]newarray if only one dimension, 457 // or if all non-final dimensions are small constants. 458 if (ndimensions == 1 || (1 <= expand_count && expand_count <= expand_limit)) { 459 Node* obj = NULL; 460 // Set the original stack and the reexecute bit for the interpreter 461 // to reexecute the multianewarray bytecode if deoptimization happens. 462 // Do it unconditionally even for one dimension multianewarray. 463 // Note: the reexecute bit will be set in GraphKit::add_safepoint_edges() 464 // when AllocateArray node for newarray is created. 465 { PreserveReexecuteState preexecs(this); 466 _sp += ndimensions; 467 // Pass 0 as nargs since uncommon trap code does not need to restore stack. 468 obj = expand_multianewarray(array_klass, &length[0], ndimensions, 0); 469 } //original reexecute and sp are set back here 470 push(obj); 471 return; 472 } 473 474 address fun = NULL; 475 switch (ndimensions) { 476 case 1: ShouldNotReachHere(); break; 477 case 2: fun = OptoRuntime::multianewarray2_Java(); break; 478 case 3: fun = OptoRuntime::multianewarray3_Java(); break; 479 case 4: fun = OptoRuntime::multianewarray4_Java(); break; 480 case 5: fun = OptoRuntime::multianewarray5_Java(); break; 481 }; 482 Node* c = NULL; 483 484 if (fun != NULL) { 485 c = make_runtime_call(RC_NO_LEAF | RC_NO_IO, 486 OptoRuntime::multianewarray_Type(ndimensions), 487 fun, NULL, TypeRawPtr::BOTTOM, 488 makecon(TypeKlassPtr::make(array_klass)), 489 length[0], length[1], length[2], 490 length[3], length[4]); 491 } else { 492 // Create a java array for dimension sizes 493 Node* dims = NULL; 494 { PreserveReexecuteState preexecs(this); 495 _sp += ndimensions; 496 Node* dims_array_klass = makecon(TypeKlassPtr::make(ciArrayKlass::make(ciType::make(T_INT)))); 497 dims = new_array(dims_array_klass, intcon(ndimensions), 0); 498 499 // Fill-in it with values 500 for (j = 0; j < ndimensions; j++) { 501 Node *dims_elem = array_element_address(dims, intcon(j), T_INT); 502 store_to_memory(control(), dims_elem, length[j], T_INT, TypeAryPtr::INTS); 503 } 504 } 505 506 c = make_runtime_call(RC_NO_LEAF | RC_NO_IO, 507 OptoRuntime::multianewarrayN_Type(), 508 OptoRuntime::multianewarrayN_Java(), NULL, TypeRawPtr::BOTTOM, 509 makecon(TypeKlassPtr::make(array_klass)), 510 dims); 511 } 512 513 Node* res = _gvn.transform(new (C) ProjNode(c, TypeFunc::Parms)); 514 515 const Type* type = TypeOopPtr::make_from_klass_raw(array_klass); 516 517 // Improve the type: We know it's not null, exact, and of a given length. 518 type = type->is_ptr()->cast_to_ptr_type(TypePtr::NotNull); 519 type = type->is_aryptr()->cast_to_exactness(true); 520 521 const TypeInt* ltype = _gvn.find_int_type(length[0]); 522 if (ltype != NULL) 523 type = type->is_aryptr()->cast_to_size(ltype); 524 525 // We cannot sharpen the nested sub-arrays, since the top level is mutable. 526 527 Node* cast = _gvn.transform( new (C) CheckCastPPNode(control(), res, type) ); 528 push(cast); 529 530 // Possible improvements: 531 // - Make a fast path for small multi-arrays. (W/ implicit init. loops.) 532 // - Issue CastII against length[*] values, to TypeInt::POS. 533} 534