1 /* 2 * Copyright (c) 1997, 2018, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 * 23 */ 24 25 #include "precompiled.hpp" 26 #include "compiler/compileLog.hpp" 27 #include "gc/shared/barrierSet.hpp" 28 #include "gc/shared/c2/barrierSetC2.hpp" 29 #include "memory/allocation.inline.hpp" 30 #include "opto/addnode.hpp" 31 #include "opto/callnode.hpp" 32 #include "opto/cfgnode.hpp" 33 #include "opto/loopnode.hpp" 34 #include "opto/matcher.hpp" 35 #include "opto/movenode.hpp" 36 #include "opto/mulnode.hpp" 37 #include "opto/opcodes.hpp" 38 #include "opto/phaseX.hpp" 39 #include "opto/subnode.hpp" 40 #include "runtime/sharedRuntime.hpp" 41 42 // Portions of code courtesy of Clifford Click 43 44 // Optimization - Graph Style 45 46 #include "math.h" 47 48 //============================================================================= 49 //------------------------------Identity--------------------------------------- 50 // If right input is a constant 0, return the left input. 51 Node* SubNode::Identity(PhaseGVN* phase) { 52 assert(in(1) != this, "Must already have called Value"); 53 assert(in(2) != this, "Must already have called Value"); 54 55 // Remove double negation 56 const Type *zero = add_id(); 57 if( phase->type( in(1) )->higher_equal( zero ) && 58 in(2)->Opcode() == Opcode() && 59 phase->type( in(2)->in(1) )->higher_equal( zero ) ) { 60 return in(2)->in(2); 61 } 62 63 // Convert "(X+Y) - Y" into X and "(X+Y) - X" into Y 64 if( in(1)->Opcode() == Op_AddI ) { 65 if( phase->eqv(in(1)->in(2),in(2)) ) 66 return in(1)->in(1); 67 if (phase->eqv(in(1)->in(1),in(2))) 68 return in(1)->in(2); 69 70 // Also catch: "(X + Opaque2(Y)) - Y". In this case, 'Y' is a loop-varying 71 // trip counter and X is likely to be loop-invariant (that's how O2 Nodes 72 // are originally used, although the optimizer sometimes jiggers things). 73 // This folding through an O2 removes a loop-exit use of a loop-varying 74 // value and generally lowers register pressure in and around the loop. 75 if( in(1)->in(2)->Opcode() == Op_Opaque2 && 76 phase->eqv(in(1)->in(2)->in(1),in(2)) ) 77 return in(1)->in(1); 78 } 79 80 return ( phase->type( in(2) )->higher_equal( zero ) ) ? in(1) : this; 81 } 82 83 //------------------------------Value------------------------------------------ 84 // A subtract node differences it's two inputs. 85 const Type* SubNode::Value_common(PhaseTransform *phase) const { 86 const Node* in1 = in(1); 87 const Node* in2 = in(2); 88 // Either input is TOP ==> the result is TOP 89 const Type* t1 = (in1 == this) ? Type::TOP : phase->type(in1); 90 if( t1 == Type::TOP ) return Type::TOP; 91 const Type* t2 = (in2 == this) ? Type::TOP : phase->type(in2); 92 if( t2 == Type::TOP ) return Type::TOP; 93 94 // Not correct for SubFnode and AddFNode (must check for infinity) 95 // Equal? Subtract is zero 96 if (in1->eqv_uncast(in2)) return add_id(); 97 98 // Either input is BOTTOM ==> the result is the local BOTTOM 99 if( t1 == Type::BOTTOM || t2 == Type::BOTTOM ) 100 return bottom_type(); 101 102 return NULL; 103 } 104 105 const Type* SubNode::Value(PhaseGVN* phase) const { 106 const Type* t = Value_common(phase); 107 if (t != NULL) { 108 return t; 109 } 110 const Type* t1 = phase->type(in(1)); 111 const Type* t2 = phase->type(in(2)); 112 return sub(t1,t2); // Local flavor of type subtraction 113 114 } 115 116 //============================================================================= 117 //------------------------------Helper function-------------------------------- 118 119 static bool is_cloop_increment(Node* inc) { 120 precond(inc->Opcode() == Op_AddI || inc->Opcode() == Op_AddL); 121 122 if (!inc->in(1)->is_Phi()) { 123 return false; 124 } 125 const PhiNode* phi = inc->in(1)->as_Phi(); 126 127 if (phi->is_copy() || !phi->region()->is_CountedLoop()) { 128 return false; 129 } 130 131 return inc == phi->region()->as_CountedLoop()->incr(); 132 } 133 134 // Given the expression '(x + C) - v', or 135 // 'v - (x + C)', we examine nodes '+' and 'v': 136 // 137 // 1. Do not convert if '+' is a counted-loop increment, because the '-' is 138 // loop invariant and converting extends the live-range of 'x' to overlap 139 // with the '+', forcing another register to be used in the loop. 140 // 141 // 2. Do not convert if 'v' is a counted-loop induction variable, because 142 // 'x' might be invariant. 143 // 144 static bool ok_to_convert(Node* inc, Node* var) { 145 return !(is_cloop_increment(inc) || var->is_cloop_ind_var()); 146 } 147 148 //------------------------------Ideal------------------------------------------ 149 Node *SubINode::Ideal(PhaseGVN *phase, bool can_reshape){ 150 Node *in1 = in(1); 151 Node *in2 = in(2); 152 uint op1 = in1->Opcode(); 153 uint op2 = in2->Opcode(); 154 155 #ifdef ASSERT 156 // Check for dead loop 157 if( phase->eqv( in1, this ) || phase->eqv( in2, this ) || 158 ( ( op1 == Op_AddI || op1 == Op_SubI ) && 159 ( phase->eqv( in1->in(1), this ) || phase->eqv( in1->in(2), this ) || 160 phase->eqv( in1->in(1), in1 ) || phase->eqv( in1->in(2), in1 ) ) ) ) 161 assert(false, "dead loop in SubINode::Ideal"); 162 #endif 163 164 const Type *t2 = phase->type( in2 ); 165 if( t2 == Type::TOP ) return NULL; 166 // Convert "x-c0" into "x+ -c0". 167 if( t2->base() == Type::Int ){ // Might be bottom or top... 168 const TypeInt *i = t2->is_int(); 169 if( i->is_con() ) 170 return new AddINode(in1, phase->intcon(-i->get_con())); 171 } 172 173 // Convert "(x+c0) - y" into (x-y) + c0" 174 // Do not collapse (x+c0)-y if "+" is a loop increment or 175 // if "y" is a loop induction variable. 176 if( op1 == Op_AddI && ok_to_convert(in1, in2) ) { 177 const Type *tadd = phase->type( in1->in(2) ); 178 if( tadd->singleton() && tadd != Type::TOP ) { 179 Node *sub2 = phase->transform( new SubINode( in1->in(1), in2 )); 180 return new AddINode( sub2, in1->in(2) ); 181 } 182 } 183 184 185 // Convert "x - (y+c0)" into "(x-y) - c0" 186 // Need the same check as in above optimization but reversed. 187 if (op2 == Op_AddI && ok_to_convert(in2, in1)) { 188 Node* in21 = in2->in(1); 189 Node* in22 = in2->in(2); 190 const TypeInt* tcon = phase->type(in22)->isa_int(); 191 if (tcon != NULL && tcon->is_con()) { 192 Node* sub2 = phase->transform( new SubINode(in1, in21) ); 193 Node* neg_c0 = phase->intcon(- tcon->get_con()); 194 return new AddINode(sub2, neg_c0); 195 } 196 } 197 198 const Type *t1 = phase->type( in1 ); 199 if( t1 == Type::TOP ) return NULL; 200 201 #ifdef ASSERT 202 // Check for dead loop 203 if( ( op2 == Op_AddI || op2 == Op_SubI ) && 204 ( phase->eqv( in2->in(1), this ) || phase->eqv( in2->in(2), this ) || 205 phase->eqv( in2->in(1), in2 ) || phase->eqv( in2->in(2), in2 ) ) ) 206 assert(false, "dead loop in SubINode::Ideal"); 207 #endif 208 209 // Convert "x - (x+y)" into "-y" 210 if( op2 == Op_AddI && 211 phase->eqv( in1, in2->in(1) ) ) 212 return new SubINode( phase->intcon(0),in2->in(2)); 213 // Convert "(x-y) - x" into "-y" 214 if( op1 == Op_SubI && 215 phase->eqv( in1->in(1), in2 ) ) 216 return new SubINode( phase->intcon(0),in1->in(2)); 217 // Convert "x - (y+x)" into "-y" 218 if( op2 == Op_AddI && 219 phase->eqv( in1, in2->in(2) ) ) 220 return new SubINode( phase->intcon(0),in2->in(1)); 221 222 // Convert "0 - (x-y)" into "y-x" 223 if( t1 == TypeInt::ZERO && op2 == Op_SubI ) 224 return new SubINode( in2->in(2), in2->in(1) ); 225 226 // Convert "0 - (x+con)" into "-con-x" 227 jint con; 228 if( t1 == TypeInt::ZERO && op2 == Op_AddI && 229 (con = in2->in(2)->find_int_con(0)) != 0 ) 230 return new SubINode( phase->intcon(-con), in2->in(1) ); 231 232 // Convert "(X+A) - (X+B)" into "A - B" 233 if( op1 == Op_AddI && op2 == Op_AddI && in1->in(1) == in2->in(1) ) 234 return new SubINode( in1->in(2), in2->in(2) ); 235 236 // Convert "(A+X) - (B+X)" into "A - B" 237 if( op1 == Op_AddI && op2 == Op_AddI && in1->in(2) == in2->in(2) ) 238 return new SubINode( in1->in(1), in2->in(1) ); 239 240 // Convert "(A+X) - (X+B)" into "A - B" 241 if( op1 == Op_AddI && op2 == Op_AddI && in1->in(2) == in2->in(1) ) 242 return new SubINode( in1->in(1), in2->in(2) ); 243 244 // Convert "(X+A) - (B+X)" into "A - B" 245 if( op1 == Op_AddI && op2 == Op_AddI && in1->in(1) == in2->in(2) ) 246 return new SubINode( in1->in(2), in2->in(1) ); 247 248 // Convert "A-(B-C)" into (A+C)-B", since add is commutative and generally 249 // nicer to optimize than subtract. 250 if( op2 == Op_SubI && in2->outcnt() == 1) { 251 Node *add1 = phase->transform( new AddINode( in1, in2->in(2) ) ); 252 return new SubINode( add1, in2->in(1) ); 253 } 254 255 return NULL; 256 } 257 258 //------------------------------sub-------------------------------------------- 259 // A subtract node differences it's two inputs. 260 const Type *SubINode::sub( const Type *t1, const Type *t2 ) const { 261 const TypeInt *r0 = t1->is_int(); // Handy access 262 const TypeInt *r1 = t2->is_int(); 263 int32_t lo = java_subtract(r0->_lo, r1->_hi); 264 int32_t hi = java_subtract(r0->_hi, r1->_lo); 265 266 // We next check for 32-bit overflow. 267 // If that happens, we just assume all integers are possible. 268 if( (((r0->_lo ^ r1->_hi) >= 0) || // lo ends have same signs OR 269 ((r0->_lo ^ lo) >= 0)) && // lo results have same signs AND 270 (((r0->_hi ^ r1->_lo) >= 0) || // hi ends have same signs OR 271 ((r0->_hi ^ hi) >= 0)) ) // hi results have same signs 272 return TypeInt::make(lo,hi,MAX2(r0->_widen,r1->_widen)); 273 else // Overflow; assume all integers 274 return TypeInt::INT; 275 } 276 277 //============================================================================= 278 //------------------------------Ideal------------------------------------------ 279 Node *SubLNode::Ideal(PhaseGVN *phase, bool can_reshape) { 280 Node *in1 = in(1); 281 Node *in2 = in(2); 282 uint op1 = in1->Opcode(); 283 uint op2 = in2->Opcode(); 284 285 #ifdef ASSERT 286 // Check for dead loop 287 if( phase->eqv( in1, this ) || phase->eqv( in2, this ) || 288 ( ( op1 == Op_AddL || op1 == Op_SubL ) && 289 ( phase->eqv( in1->in(1), this ) || phase->eqv( in1->in(2), this ) || 290 phase->eqv( in1->in(1), in1 ) || phase->eqv( in1->in(2), in1 ) ) ) ) 291 assert(false, "dead loop in SubLNode::Ideal"); 292 #endif 293 294 if( phase->type( in2 ) == Type::TOP ) return NULL; 295 const TypeLong *i = phase->type( in2 )->isa_long(); 296 // Convert "x-c0" into "x+ -c0". 297 if( i && // Might be bottom or top... 298 i->is_con() ) 299 return new AddLNode(in1, phase->longcon(-i->get_con())); 300 301 // Convert "(x+c0) - y" into (x-y) + c0" 302 // Do not collapse (x+c0)-y if "+" is a loop increment or 303 // if "y" is a loop induction variable. 304 if( op1 == Op_AddL && ok_to_convert(in1, in2) ) { 305 Node *in11 = in1->in(1); 306 const Type *tadd = phase->type( in1->in(2) ); 307 if( tadd->singleton() && tadd != Type::TOP ) { 308 Node *sub2 = phase->transform( new SubLNode( in11, in2 )); 309 return new AddLNode( sub2, in1->in(2) ); 310 } 311 } 312 313 // Convert "x - (y+c0)" into "(x-y) - c0" 314 // Need the same check as in above optimization but reversed. 315 if (op2 == Op_AddL && ok_to_convert(in2, in1)) { 316 Node* in21 = in2->in(1); 317 Node* in22 = in2->in(2); 318 const TypeLong* tcon = phase->type(in22)->isa_long(); 319 if (tcon != NULL && tcon->is_con()) { 320 Node* sub2 = phase->transform( new SubLNode(in1, in21) ); 321 Node* neg_c0 = phase->longcon(- tcon->get_con()); 322 return new AddLNode(sub2, neg_c0); 323 } 324 } 325 326 const Type *t1 = phase->type( in1 ); 327 if( t1 == Type::TOP ) return NULL; 328 329 #ifdef ASSERT 330 // Check for dead loop 331 if( ( op2 == Op_AddL || op2 == Op_SubL ) && 332 ( phase->eqv( in2->in(1), this ) || phase->eqv( in2->in(2), this ) || 333 phase->eqv( in2->in(1), in2 ) || phase->eqv( in2->in(2), in2 ) ) ) 334 assert(false, "dead loop in SubLNode::Ideal"); 335 #endif 336 337 // Convert "x - (x+y)" into "-y" 338 if( op2 == Op_AddL && 339 phase->eqv( in1, in2->in(1) ) ) 340 return new SubLNode( phase->makecon(TypeLong::ZERO), in2->in(2)); 341 // Convert "x - (y+x)" into "-y" 342 if( op2 == Op_AddL && 343 phase->eqv( in1, in2->in(2) ) ) 344 return new SubLNode( phase->makecon(TypeLong::ZERO),in2->in(1)); 345 346 // Convert "0 - (x-y)" into "y-x" 347 if( phase->type( in1 ) == TypeLong::ZERO && op2 == Op_SubL ) 348 return new SubLNode( in2->in(2), in2->in(1) ); 349 350 // Convert "(X+A) - (X+B)" into "A - B" 351 if( op1 == Op_AddL && op2 == Op_AddL && in1->in(1) == in2->in(1) ) 352 return new SubLNode( in1->in(2), in2->in(2) ); 353 354 // Convert "(A+X) - (B+X)" into "A - B" 355 if( op1 == Op_AddL && op2 == Op_AddL && in1->in(2) == in2->in(2) ) 356 return new SubLNode( in1->in(1), in2->in(1) ); 357 358 // Convert "A-(B-C)" into (A+C)-B" 359 if( op2 == Op_SubL && in2->outcnt() == 1) { 360 Node *add1 = phase->transform( new AddLNode( in1, in2->in(2) ) ); 361 return new SubLNode( add1, in2->in(1) ); 362 } 363 364 return NULL; 365 } 366 367 //------------------------------sub-------------------------------------------- 368 // A subtract node differences it's two inputs. 369 const Type *SubLNode::sub( const Type *t1, const Type *t2 ) const { 370 const TypeLong *r0 = t1->is_long(); // Handy access 371 const TypeLong *r1 = t2->is_long(); 372 jlong lo = java_subtract(r0->_lo, r1->_hi); 373 jlong hi = java_subtract(r0->_hi, r1->_lo); 374 375 // We next check for 32-bit overflow. 376 // If that happens, we just assume all integers are possible. 377 if( (((r0->_lo ^ r1->_hi) >= 0) || // lo ends have same signs OR 378 ((r0->_lo ^ lo) >= 0)) && // lo results have same signs AND 379 (((r0->_hi ^ r1->_lo) >= 0) || // hi ends have same signs OR 380 ((r0->_hi ^ hi) >= 0)) ) // hi results have same signs 381 return TypeLong::make(lo,hi,MAX2(r0->_widen,r1->_widen)); 382 else // Overflow; assume all integers 383 return TypeLong::LONG; 384 } 385 386 //============================================================================= 387 //------------------------------Value------------------------------------------ 388 // A subtract node differences its two inputs. 389 const Type* SubFPNode::Value(PhaseGVN* phase) const { 390 const Node* in1 = in(1); 391 const Node* in2 = in(2); 392 // Either input is TOP ==> the result is TOP 393 const Type* t1 = (in1 == this) ? Type::TOP : phase->type(in1); 394 if( t1 == Type::TOP ) return Type::TOP; 395 const Type* t2 = (in2 == this) ? Type::TOP : phase->type(in2); 396 if( t2 == Type::TOP ) return Type::TOP; 397 398 // if both operands are infinity of same sign, the result is NaN; do 399 // not replace with zero 400 if( (t1->is_finite() && t2->is_finite()) ) { 401 if( phase->eqv(in1, in2) ) return add_id(); 402 } 403 404 // Either input is BOTTOM ==> the result is the local BOTTOM 405 const Type *bot = bottom_type(); 406 if( (t1 == bot) || (t2 == bot) || 407 (t1 == Type::BOTTOM) || (t2 == Type::BOTTOM) ) 408 return bot; 409 410 return sub(t1,t2); // Local flavor of type subtraction 411 } 412 413 414 //============================================================================= 415 //------------------------------Ideal------------------------------------------ 416 Node *SubFNode::Ideal(PhaseGVN *phase, bool can_reshape) { 417 const Type *t2 = phase->type( in(2) ); 418 // Convert "x-c0" into "x+ -c0". 419 if( t2->base() == Type::FloatCon ) { // Might be bottom or top... 420 // return new (phase->C, 3) AddFNode(in(1), phase->makecon( TypeF::make(-t2->getf()) ) ); 421 } 422 423 // Not associative because of boundary conditions (infinity) 424 if( IdealizedNumerics && !phase->C->method()->is_strict() ) { 425 // Convert "x - (x+y)" into "-y" 426 if( in(2)->is_Add() && 427 phase->eqv(in(1),in(2)->in(1) ) ) 428 return new SubFNode( phase->makecon(TypeF::ZERO),in(2)->in(2)); 429 } 430 431 // Cannot replace 0.0-X with -X because a 'fsub' bytecode computes 432 // 0.0-0.0 as +0.0, while a 'fneg' bytecode computes -0.0. 433 //if( phase->type(in(1)) == TypeF::ZERO ) 434 //return new (phase->C, 2) NegFNode(in(2)); 435 436 return NULL; 437 } 438 439 //------------------------------sub-------------------------------------------- 440 // A subtract node differences its two inputs. 441 const Type *SubFNode::sub( const Type *t1, const Type *t2 ) const { 442 // no folding if one of operands is infinity or NaN, do not do constant folding 443 if( g_isfinite(t1->getf()) && g_isfinite(t2->getf()) ) { 444 return TypeF::make( t1->getf() - t2->getf() ); 445 } 446 else if( g_isnan(t1->getf()) ) { 447 return t1; 448 } 449 else if( g_isnan(t2->getf()) ) { 450 return t2; 451 } 452 else { 453 return Type::FLOAT; 454 } 455 } 456 457 //============================================================================= 458 //------------------------------Ideal------------------------------------------ 459 Node *SubDNode::Ideal(PhaseGVN *phase, bool can_reshape){ 460 const Type *t2 = phase->type( in(2) ); 461 // Convert "x-c0" into "x+ -c0". 462 if( t2->base() == Type::DoubleCon ) { // Might be bottom or top... 463 // return new (phase->C, 3) AddDNode(in(1), phase->makecon( TypeD::make(-t2->getd()) ) ); 464 } 465 466 // Not associative because of boundary conditions (infinity) 467 if( IdealizedNumerics && !phase->C->method()->is_strict() ) { 468 // Convert "x - (x+y)" into "-y" 469 if( in(2)->is_Add() && 470 phase->eqv(in(1),in(2)->in(1) ) ) 471 return new SubDNode( phase->makecon(TypeD::ZERO),in(2)->in(2)); 472 } 473 474 // Cannot replace 0.0-X with -X because a 'dsub' bytecode computes 475 // 0.0-0.0 as +0.0, while a 'dneg' bytecode computes -0.0. 476 //if( phase->type(in(1)) == TypeD::ZERO ) 477 //return new (phase->C, 2) NegDNode(in(2)); 478 479 return NULL; 480 } 481 482 //------------------------------sub-------------------------------------------- 483 // A subtract node differences its two inputs. 484 const Type *SubDNode::sub( const Type *t1, const Type *t2 ) const { 485 // no folding if one of operands is infinity or NaN, do not do constant folding 486 if( g_isfinite(t1->getd()) && g_isfinite(t2->getd()) ) { 487 return TypeD::make( t1->getd() - t2->getd() ); 488 } 489 else if( g_isnan(t1->getd()) ) { 490 return t1; 491 } 492 else if( g_isnan(t2->getd()) ) { 493 return t2; 494 } 495 else { 496 return Type::DOUBLE; 497 } 498 } 499 500 //============================================================================= 501 //------------------------------Idealize--------------------------------------- 502 // Unlike SubNodes, compare must still flatten return value to the 503 // range -1, 0, 1. 504 // And optimizations like those for (X + Y) - X fail if overflow happens. 505 Node* CmpNode::Identity(PhaseGVN* phase) { 506 return this; 507 } 508 509 #ifndef PRODUCT 510 //----------------------------related------------------------------------------ 511 // Related nodes of comparison nodes include all data inputs (until hitting a 512 // control boundary) as well as all outputs until and including control nodes 513 // as well as their projections. In compact mode, data inputs till depth 1 and 514 // all outputs till depth 1 are considered. 515 void CmpNode::related(GrowableArray<Node*> *in_rel, GrowableArray<Node*> *out_rel, bool compact) const { 516 if (compact) { 517 this->collect_nodes(in_rel, 1, false, true); 518 this->collect_nodes(out_rel, -1, false, false); 519 } else { 520 this->collect_nodes_in_all_data(in_rel, false); 521 this->collect_nodes_out_all_ctrl_boundary(out_rel); 522 // Now, find all control nodes in out_rel, and include their projections 523 // and projection targets (if any) in the result. 524 GrowableArray<Node*> proj(Compile::current()->unique()); 525 for (GrowableArrayIterator<Node*> it = out_rel->begin(); it != out_rel->end(); ++it) { 526 Node* n = *it; 527 if (n->is_CFG() && !n->is_Proj()) { 528 // Assume projections and projection targets are found at levels 1 and 2. 529 n->collect_nodes(&proj, -2, false, false); 530 for (GrowableArrayIterator<Node*> p = proj.begin(); p != proj.end(); ++p) { 531 out_rel->append_if_missing(*p); 532 } 533 proj.clear(); 534 } 535 } 536 } 537 } 538 #endif 539 540 //============================================================================= 541 //------------------------------cmp-------------------------------------------- 542 // Simplify a CmpI (compare 2 integers) node, based on local information. 543 // If both inputs are constants, compare them. 544 const Type *CmpINode::sub( const Type *t1, const Type *t2 ) const { 545 const TypeInt *r0 = t1->is_int(); // Handy access 546 const TypeInt *r1 = t2->is_int(); 547 548 if( r0->_hi < r1->_lo ) // Range is always low? 549 return TypeInt::CC_LT; 550 else if( r0->_lo > r1->_hi ) // Range is always high? 551 return TypeInt::CC_GT; 552 553 else if( r0->is_con() && r1->is_con() ) { // comparing constants? 554 assert(r0->get_con() == r1->get_con(), "must be equal"); 555 return TypeInt::CC_EQ; // Equal results. 556 } else if( r0->_hi == r1->_lo ) // Range is never high? 557 return TypeInt::CC_LE; 558 else if( r0->_lo == r1->_hi ) // Range is never low? 559 return TypeInt::CC_GE; 560 return TypeInt::CC; // else use worst case results 561 } 562 563 // Simplify a CmpU (compare 2 integers) node, based on local information. 564 // If both inputs are constants, compare them. 565 const Type *CmpUNode::sub( const Type *t1, const Type *t2 ) const { 566 assert(!t1->isa_ptr(), "obsolete usage of CmpU"); 567 568 // comparing two unsigned ints 569 const TypeInt *r0 = t1->is_int(); // Handy access 570 const TypeInt *r1 = t2->is_int(); 571 572 // Current installed version 573 // Compare ranges for non-overlap 574 juint lo0 = r0->_lo; 575 juint hi0 = r0->_hi; 576 juint lo1 = r1->_lo; 577 juint hi1 = r1->_hi; 578 579 // If either one has both negative and positive values, 580 // it therefore contains both 0 and -1, and since [0..-1] is the 581 // full unsigned range, the type must act as an unsigned bottom. 582 bool bot0 = ((jint)(lo0 ^ hi0) < 0); 583 bool bot1 = ((jint)(lo1 ^ hi1) < 0); 584 585 if (bot0 || bot1) { 586 // All unsigned values are LE -1 and GE 0. 587 if (lo0 == 0 && hi0 == 0) { 588 return TypeInt::CC_LE; // 0 <= bot 589 } else if ((jint)lo0 == -1 && (jint)hi0 == -1) { 590 return TypeInt::CC_GE; // -1 >= bot 591 } else if (lo1 == 0 && hi1 == 0) { 592 return TypeInt::CC_GE; // bot >= 0 593 } else if ((jint)lo1 == -1 && (jint)hi1 == -1) { 594 return TypeInt::CC_LE; // bot <= -1 595 } 596 } else { 597 // We can use ranges of the form [lo..hi] if signs are the same. 598 assert(lo0 <= hi0 && lo1 <= hi1, "unsigned ranges are valid"); 599 // results are reversed, '-' > '+' for unsigned compare 600 if (hi0 < lo1) { 601 return TypeInt::CC_LT; // smaller 602 } else if (lo0 > hi1) { 603 return TypeInt::CC_GT; // greater 604 } else if (hi0 == lo1 && lo0 == hi1) { 605 return TypeInt::CC_EQ; // Equal results 606 } else if (lo0 >= hi1) { 607 return TypeInt::CC_GE; 608 } else if (hi0 <= lo1) { 609 // Check for special case in Hashtable::get. (See below.) 610 if ((jint)lo0 >= 0 && (jint)lo1 >= 0 && is_index_range_check()) 611 return TypeInt::CC_LT; 612 return TypeInt::CC_LE; 613 } 614 } 615 // Check for special case in Hashtable::get - the hash index is 616 // mod'ed to the table size so the following range check is useless. 617 // Check for: (X Mod Y) CmpU Y, where the mod result and Y both have 618 // to be positive. 619 // (This is a gross hack, since the sub method never 620 // looks at the structure of the node in any other case.) 621 if ((jint)lo0 >= 0 && (jint)lo1 >= 0 && is_index_range_check()) 622 return TypeInt::CC_LT; 623 return TypeInt::CC; // else use worst case results 624 } 625 626 const Type* CmpUNode::Value(PhaseGVN* phase) const { 627 const Type* t = SubNode::Value_common(phase); 628 if (t != NULL) { 629 return t; 630 } 631 const Node* in1 = in(1); 632 const Node* in2 = in(2); 633 const Type* t1 = phase->type(in1); 634 const Type* t2 = phase->type(in2); 635 assert(t1->isa_int(), "CmpU has only Int type inputs"); 636 if (t2 == TypeInt::INT) { // Compare to bottom? 637 return bottom_type(); 638 } 639 uint in1_op = in1->Opcode(); 640 if (in1_op == Op_AddI || in1_op == Op_SubI) { 641 // The problem rise when result of AddI(SubI) may overflow 642 // signed integer value. Let say the input type is 643 // [256, maxint] then +128 will create 2 ranges due to 644 // overflow: [minint, minint+127] and [384, maxint]. 645 // But C2 type system keep only 1 type range and as result 646 // it use general [minint, maxint] for this case which we 647 // can't optimize. 648 // 649 // Make 2 separate type ranges based on types of AddI(SubI) inputs 650 // and compare results of their compare. If results are the same 651 // CmpU node can be optimized. 652 const Node* in11 = in1->in(1); 653 const Node* in12 = in1->in(2); 654 const Type* t11 = (in11 == in1) ? Type::TOP : phase->type(in11); 655 const Type* t12 = (in12 == in1) ? Type::TOP : phase->type(in12); 656 // Skip cases when input types are top or bottom. 657 if ((t11 != Type::TOP) && (t11 != TypeInt::INT) && 658 (t12 != Type::TOP) && (t12 != TypeInt::INT)) { 659 const TypeInt *r0 = t11->is_int(); 660 const TypeInt *r1 = t12->is_int(); 661 jlong lo_r0 = r0->_lo; 662 jlong hi_r0 = r0->_hi; 663 jlong lo_r1 = r1->_lo; 664 jlong hi_r1 = r1->_hi; 665 if (in1_op == Op_SubI) { 666 jlong tmp = hi_r1; 667 hi_r1 = -lo_r1; 668 lo_r1 = -tmp; 669 // Note, for substructing [minint,x] type range 670 // long arithmetic provides correct overflow answer. 671 // The confusion come from the fact that in 32-bit 672 // -minint == minint but in 64-bit -minint == maxint+1. 673 } 674 jlong lo_long = lo_r0 + lo_r1; 675 jlong hi_long = hi_r0 + hi_r1; 676 int lo_tr1 = min_jint; 677 int hi_tr1 = (int)hi_long; 678 int lo_tr2 = (int)lo_long; 679 int hi_tr2 = max_jint; 680 bool underflow = lo_long != (jlong)lo_tr2; 681 bool overflow = hi_long != (jlong)hi_tr1; 682 // Use sub(t1, t2) when there is no overflow (one type range) 683 // or when both overflow and underflow (too complex). 684 if ((underflow != overflow) && (hi_tr1 < lo_tr2)) { 685 // Overflow only on one boundary, compare 2 separate type ranges. 686 int w = MAX2(r0->_widen, r1->_widen); // _widen does not matter here 687 const TypeInt* tr1 = TypeInt::make(lo_tr1, hi_tr1, w); 688 const TypeInt* tr2 = TypeInt::make(lo_tr2, hi_tr2, w); 689 const Type* cmp1 = sub(tr1, t2); 690 const Type* cmp2 = sub(tr2, t2); 691 if (cmp1 == cmp2) { 692 return cmp1; // Hit! 693 } 694 } 695 } 696 } 697 698 return sub(t1, t2); // Local flavor of type subtraction 699 } 700 701 bool CmpUNode::is_index_range_check() const { 702 // Check for the "(X ModI Y) CmpU Y" shape 703 return (in(1)->Opcode() == Op_ModI && 704 in(1)->in(2)->eqv_uncast(in(2))); 705 } 706 707 //------------------------------Idealize--------------------------------------- 708 Node *CmpINode::Ideal( PhaseGVN *phase, bool can_reshape ) { 709 if (phase->type(in(2))->higher_equal(TypeInt::ZERO)) { 710 switch (in(1)->Opcode()) { 711 case Op_CmpL3: // Collapse a CmpL3/CmpI into a CmpL 712 return new CmpLNode(in(1)->in(1),in(1)->in(2)); 713 case Op_CmpF3: // Collapse a CmpF3/CmpI into a CmpF 714 return new CmpFNode(in(1)->in(1),in(1)->in(2)); 715 case Op_CmpD3: // Collapse a CmpD3/CmpI into a CmpD 716 return new CmpDNode(in(1)->in(1),in(1)->in(2)); 717 //case Op_SubI: 718 // If (x - y) cannot overflow, then ((x - y) <?> 0) 719 // can be turned into (x <?> y). 720 // This is handled (with more general cases) by Ideal_sub_algebra. 721 } 722 } 723 return NULL; // No change 724 } 725 726 //------------------------------Ideal------------------------------------------ 727 Node* CmpLNode::Ideal(PhaseGVN* phase, bool can_reshape) { 728 Node* a = NULL; 729 Node* b = NULL; 730 if (is_double_null_check(phase, a, b) && (phase->type(a)->is_zero_type() || phase->type(b)->is_zero_type())) { 731 // Degraded to a simple null check, use old acmp 732 return new CmpPNode(a, b); 733 } 734 return NULL; 735 } 736 737 // Match double null check emitted by Compile::optimize_acmp() 738 bool CmpLNode::is_double_null_check(PhaseGVN* phase, Node*& a, Node*& b) const { 739 if (in(1)->Opcode() == Op_OrL && 740 in(1)->in(1)->Opcode() == Op_CastP2X && 741 in(1)->in(2)->Opcode() == Op_CastP2X && 742 in(2)->bottom_type()->is_zero_type()) { 743 assert(EnableValhalla, "unexpected double null check"); 744 a = in(1)->in(1)->in(1); 745 b = in(1)->in(2)->in(1); 746 return true; 747 } 748 return false; 749 } 750 751 //------------------------------Value------------------------------------------ 752 const Type* CmpLNode::Value(PhaseGVN* phase) const { 753 Node* a = NULL; 754 Node* b = NULL; 755 if (is_double_null_check(phase, a, b) && (!phase->type(a)->maybe_null() || !phase->type(b)->maybe_null())) { 756 // One operand is never NULL, emit constant false 757 return TypeInt::CC_GT; 758 } 759 return SubNode::Value(phase); 760 } 761 762 //============================================================================= 763 // Simplify a CmpL (compare 2 longs ) node, based on local information. 764 // If both inputs are constants, compare them. 765 const Type *CmpLNode::sub( const Type *t1, const Type *t2 ) const { 766 const TypeLong *r0 = t1->is_long(); // Handy access 767 const TypeLong *r1 = t2->is_long(); 768 769 if( r0->_hi < r1->_lo ) // Range is always low? 770 return TypeInt::CC_LT; 771 else if( r0->_lo > r1->_hi ) // Range is always high? 772 return TypeInt::CC_GT; 773 774 else if( r0->is_con() && r1->is_con() ) { // comparing constants? 775 assert(r0->get_con() == r1->get_con(), "must be equal"); 776 return TypeInt::CC_EQ; // Equal results. 777 } else if( r0->_hi == r1->_lo ) // Range is never high? 778 return TypeInt::CC_LE; 779 else if( r0->_lo == r1->_hi ) // Range is never low? 780 return TypeInt::CC_GE; 781 return TypeInt::CC; // else use worst case results 782 } 783 784 785 // Simplify a CmpUL (compare 2 unsigned longs) node, based on local information. 786 // If both inputs are constants, compare them. 787 const Type* CmpULNode::sub(const Type* t1, const Type* t2) const { 788 assert(!t1->isa_ptr(), "obsolete usage of CmpUL"); 789 790 // comparing two unsigned longs 791 const TypeLong* r0 = t1->is_long(); // Handy access 792 const TypeLong* r1 = t2->is_long(); 793 794 // Current installed version 795 // Compare ranges for non-overlap 796 julong lo0 = r0->_lo; 797 julong hi0 = r0->_hi; 798 julong lo1 = r1->_lo; 799 julong hi1 = r1->_hi; 800 801 // If either one has both negative and positive values, 802 // it therefore contains both 0 and -1, and since [0..-1] is the 803 // full unsigned range, the type must act as an unsigned bottom. 804 bool bot0 = ((jlong)(lo0 ^ hi0) < 0); 805 bool bot1 = ((jlong)(lo1 ^ hi1) < 0); 806 807 if (bot0 || bot1) { 808 // All unsigned values are LE -1 and GE 0. 809 if (lo0 == 0 && hi0 == 0) { 810 return TypeInt::CC_LE; // 0 <= bot 811 } else if ((jlong)lo0 == -1 && (jlong)hi0 == -1) { 812 return TypeInt::CC_GE; // -1 >= bot 813 } else if (lo1 == 0 && hi1 == 0) { 814 return TypeInt::CC_GE; // bot >= 0 815 } else if ((jlong)lo1 == -1 && (jlong)hi1 == -1) { 816 return TypeInt::CC_LE; // bot <= -1 817 } 818 } else { 819 // We can use ranges of the form [lo..hi] if signs are the same. 820 assert(lo0 <= hi0 && lo1 <= hi1, "unsigned ranges are valid"); 821 // results are reversed, '-' > '+' for unsigned compare 822 if (hi0 < lo1) { 823 return TypeInt::CC_LT; // smaller 824 } else if (lo0 > hi1) { 825 return TypeInt::CC_GT; // greater 826 } else if (hi0 == lo1 && lo0 == hi1) { 827 return TypeInt::CC_EQ; // Equal results 828 } else if (lo0 >= hi1) { 829 return TypeInt::CC_GE; 830 } else if (hi0 <= lo1) { 831 return TypeInt::CC_LE; 832 } 833 } 834 835 return TypeInt::CC; // else use worst case results 836 } 837 838 //============================================================================= 839 //------------------------------sub-------------------------------------------- 840 // Simplify an CmpP (compare 2 pointers) node, based on local information. 841 // If both inputs are constants, compare them. 842 const Type *CmpPNode::sub( const Type *t1, const Type *t2 ) const { 843 const TypePtr *r0 = t1->is_ptr(); // Handy access 844 const TypePtr *r1 = t2->is_ptr(); 845 846 // Undefined inputs makes for an undefined result 847 if( TypePtr::above_centerline(r0->_ptr) || 848 TypePtr::above_centerline(r1->_ptr) ) 849 return Type::TOP; 850 851 if (r0 == r1 && r0->singleton()) { 852 // Equal pointer constants (klasses, nulls, etc.) 853 return TypeInt::CC_EQ; 854 } 855 856 // See if it is 2 unrelated classes. 857 const TypeOopPtr* p0 = r0->isa_oopptr(); 858 const TypeOopPtr* p1 = r1->isa_oopptr(); 859 if (p0 && p1) { 860 Node* in1 = in(1)->uncast(); 861 Node* in2 = in(2)->uncast(); 862 AllocateNode* alloc1 = AllocateNode::Ideal_allocation(in1, NULL); 863 AllocateNode* alloc2 = AllocateNode::Ideal_allocation(in2, NULL); 864 if (MemNode::detect_ptr_independence(in1, alloc1, in2, alloc2, NULL)) { 865 return TypeInt::CC_GT; // different pointers 866 } 867 ciKlass* klass0 = p0->klass(); 868 bool xklass0 = p0->klass_is_exact(); 869 ciKlass* klass1 = p1->klass(); 870 bool xklass1 = p1->klass_is_exact(); 871 int kps = (p0->isa_klassptr()?1:0) + (p1->isa_klassptr()?1:0); 872 if (klass0 && klass1 && 873 kps != 1 && // both or neither are klass pointers 874 klass0->is_loaded() && !klass0->is_interface() && // do not trust interfaces 875 klass1->is_loaded() && !klass1->is_interface() && 876 (!klass0->is_obj_array_klass() || 877 !klass0->as_obj_array_klass()->base_element_klass()->is_interface()) && 878 (!klass1->is_obj_array_klass() || 879 !klass1->as_obj_array_klass()->base_element_klass()->is_interface())) { 880 bool unrelated_classes = false; 881 // See if neither subclasses the other, or if the class on top 882 // is precise. In either of these cases, the compare is known 883 // to fail if at least one of the pointers is provably not null. 884 if (klass0->equals(klass1)) { // if types are unequal but klasses are equal 885 // Do nothing; we know nothing for imprecise types 886 } else if (klass0->is_subtype_of(klass1)) { 887 // If klass1's type is PRECISE, then classes are unrelated. 888 unrelated_classes = xklass1; 889 } else if (klass1->is_subtype_of(klass0)) { 890 // If klass0's type is PRECISE, then classes are unrelated. 891 unrelated_classes = xklass0; 892 } else { // Neither subtypes the other 893 unrelated_classes = true; 894 } 895 if (unrelated_classes) { 896 // The oops classes are known to be unrelated. If the joined PTRs of 897 // two oops is not Null and not Bottom, then we are sure that one 898 // of the two oops is non-null, and the comparison will always fail. 899 TypePtr::PTR jp = r0->join_ptr(r1->_ptr); 900 if (jp != TypePtr::Null && jp != TypePtr::BotPTR) { 901 return TypeInt::CC_GT; 902 } 903 } 904 } 905 } 906 const TypeKlassPtr* k0 = r0->isa_klassptr(); 907 const TypeKlassPtr* k1 = r1->isa_klassptr(); 908 if (k0 && k1) { 909 if ((k0->flatten_array() && (!k1->can_be_value_type() || (k1->klass()->is_valuetype() && !k1->klass()->flatten_array()))) || 910 (k1->flatten_array() && (!k0->can_be_value_type() || (k0->klass()->is_valuetype() && !k0->klass()->flatten_array())))) { 911 return TypeInt::CC_GT; 912 } 913 } 914 915 // Known constants can be compared exactly 916 // Null can be distinguished from any NotNull pointers 917 // Unknown inputs makes an unknown result 918 if( r0->singleton() ) { 919 intptr_t bits0 = r0->get_con(); 920 if( r1->singleton() ) 921 return bits0 == r1->get_con() ? TypeInt::CC_EQ : TypeInt::CC_GT; 922 return ( r1->_ptr == TypePtr::NotNull && bits0==0 ) ? TypeInt::CC_GT : TypeInt::CC; 923 } else if( r1->singleton() ) { 924 intptr_t bits1 = r1->get_con(); 925 return ( r0->_ptr == TypePtr::NotNull && bits1==0 ) ? TypeInt::CC_GT : TypeInt::CC; 926 } else 927 return TypeInt::CC; 928 } 929 930 static inline Node* isa_java_mirror_load(PhaseGVN* phase, Node* n) { 931 // Return the klass node for (indirect load from OopHandle) 932 // LoadBarrier?(LoadP(LoadP(AddP(foo:Klass, #java_mirror)))) 933 // or NULL if not matching. 934 BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2(); 935 n = bs->step_over_gc_barrier(n); 936 937 if (n->Opcode() != Op_LoadP) return NULL; 938 939 const TypeInstPtr* tp = phase->type(n)->isa_instptr(); 940 if (!tp || tp->klass() != phase->C->env()->Class_klass()) return NULL; 941 942 Node* adr = n->in(MemNode::Address); 943 // First load from OopHandle: ((OopHandle)mirror)->resolve(); may need barrier. 944 if (adr->Opcode() != Op_LoadP || !phase->type(adr)->isa_rawptr()) return NULL; 945 adr = adr->in(MemNode::Address); 946 947 intptr_t off = 0; 948 Node* k = AddPNode::Ideal_base_and_offset(adr, phase, off); 949 if (k == NULL) return NULL; 950 const TypeKlassPtr* tkp = phase->type(k)->isa_klassptr(); 951 if (!tkp || off != in_bytes(Klass::java_mirror_offset())) return NULL; 952 953 // We've found the klass node of a Java mirror load. 954 return k; 955 } 956 957 static inline Node* isa_const_java_mirror(PhaseGVN* phase, Node* n) { 958 // for ConP(Foo.class) return ConP(Foo.klass) 959 // otherwise return NULL 960 if (!n->is_Con()) return NULL; 961 962 const TypeInstPtr* tp = phase->type(n)->isa_instptr(); 963 if (!tp) return NULL; 964 965 ciType* mirror_type = tp->java_mirror_type(); 966 // TypeInstPtr::java_mirror_type() returns non-NULL for compile- 967 // time Class constants only. 968 if (!mirror_type) return NULL; 969 970 // x.getClass() == int.class can never be true (for all primitive types) 971 // Return a ConP(NULL) node for this case. 972 if (mirror_type->is_classless()) { 973 return phase->makecon(TypePtr::NULL_PTR); 974 } 975 976 // return the ConP(Foo.klass) 977 assert(mirror_type->is_klass(), "mirror_type should represent a Klass*"); 978 return phase->makecon(TypeKlassPtr::make(mirror_type->as_klass())); 979 } 980 981 //------------------------------Ideal------------------------------------------ 982 // Normalize comparisons between Java mirror loads to compare the klass instead. 983 // 984 // Also check for the case of comparing an unknown klass loaded from the primary 985 // super-type array vs a known klass with no subtypes. This amounts to 986 // checking to see an unknown klass subtypes a known klass with no subtypes; 987 // this only happens on an exact match. We can shorten this test by 1 load. 988 Node* CmpPNode::Ideal(PhaseGVN *phase, bool can_reshape) { 989 // Normalize comparisons between Java mirrors into comparisons of the low- 990 // level klass, where a dependent load could be shortened. 991 // 992 // The new pattern has a nice effect of matching the same pattern used in the 993 // fast path of instanceof/checkcast/Class.isInstance(), which allows 994 // redundant exact type check be optimized away by GVN. 995 // For example, in 996 // if (x.getClass() == Foo.class) { 997 // Foo foo = (Foo) x; 998 // // ... use a ... 999 // } 1000 // a CmpPNode could be shared between if_acmpne and checkcast 1001 { 1002 Node* k1 = isa_java_mirror_load(phase, in(1)); 1003 Node* k2 = isa_java_mirror_load(phase, in(2)); 1004 Node* conk2 = isa_const_java_mirror(phase, in(2)); 1005 1006 if (k1 && (k2 || conk2)) { 1007 Node* lhs = k1; 1008 Node* rhs = (k2 != NULL) ? k2 : conk2; 1009 PhaseIterGVN* igvn = phase->is_IterGVN(); 1010 if (igvn != NULL) { 1011 set_req_X(1, lhs, igvn); 1012 set_req_X(2, rhs, igvn); 1013 } else { 1014 set_req(1, lhs); 1015 set_req(2, rhs); 1016 } 1017 return this; 1018 } 1019 } 1020 1021 // Constant pointer on right? 1022 const TypeKlassPtr* t2 = phase->type(in(2))->isa_klassptr(); 1023 if (t2 == NULL || !t2->klass_is_exact()) 1024 return NULL; 1025 // Get the constant klass we are comparing to. 1026 ciKlass* superklass = t2->klass(); 1027 1028 // Now check for LoadKlass on left. 1029 Node* ldk1 = in(1); 1030 if (ldk1->is_DecodeNKlass()) { 1031 ldk1 = ldk1->in(1); 1032 if (ldk1->Opcode() != Op_LoadNKlass ) 1033 return NULL; 1034 } else if (ldk1->Opcode() != Op_LoadKlass ) 1035 return NULL; 1036 // Take apart the address of the LoadKlass: 1037 Node* adr1 = ldk1->in(MemNode::Address); 1038 intptr_t con2 = 0; 1039 Node* ldk2 = AddPNode::Ideal_base_and_offset(adr1, phase, con2); 1040 if (ldk2 == NULL) 1041 return NULL; 1042 if (con2 == oopDesc::klass_offset_in_bytes()) { 1043 // We are inspecting an object's concrete class. 1044 // Short-circuit the check if the query is abstract. 1045 if (superklass->is_interface() || 1046 superklass->is_abstract()) { 1047 // Make it come out always false: 1048 this->set_req(2, phase->makecon(TypePtr::NULL_PTR)); 1049 return this; 1050 } 1051 } 1052 1053 // Check for a LoadKlass from primary supertype array. 1054 // Any nested loadklass from loadklass+con must be from the p.s. array. 1055 if (ldk2->is_DecodeNKlass()) { 1056 // Keep ldk2 as DecodeN since it could be used in CmpP below. 1057 if (ldk2->in(1)->Opcode() != Op_LoadNKlass ) 1058 return NULL; 1059 } else if (ldk2->Opcode() != Op_LoadKlass) 1060 return NULL; 1061 1062 // Verify that we understand the situation 1063 if (con2 != (intptr_t) superklass->super_check_offset()) 1064 return NULL; // Might be element-klass loading from array klass 1065 1066 // Do not fold the subtype check to an array klass pointer comparison for [V? arrays. 1067 // [V is a subtype of [V? but the klass for [V is not equal to the klass for [V?. Perform a full test. 1068 if (superklass->is_obj_array_klass()) { 1069 ciObjArrayKlass* ak = superklass->as_obj_array_klass(); 1070 if (!ak->storage_properties().is_null_free() && ak->element_klass()->is_valuetype()) { 1071 // Do not bypass the klass load from the primary supertype array 1072 return NULL; 1073 } 1074 } 1075 1076 // If 'superklass' has no subklasses and is not an interface, then we are 1077 // assured that the only input which will pass the type check is 1078 // 'superklass' itself. 1079 // 1080 // We could be more liberal here, and allow the optimization on interfaces 1081 // which have a single implementor. This would require us to increase the 1082 // expressiveness of the add_dependency() mechanism. 1083 // %%% Do this after we fix TypeOopPtr: Deps are expressive enough now. 1084 1085 // Object arrays must have their base element have no subtypes 1086 while (superklass->is_obj_array_klass()) { 1087 ciType* elem = superklass->as_obj_array_klass()->element_type(); 1088 superklass = elem->as_klass(); 1089 } 1090 if (superklass->is_instance_klass()) { 1091 ciInstanceKlass* ik = superklass->as_instance_klass(); 1092 if (ik->has_subklass() || ik->is_interface()) return NULL; 1093 // Add a dependency if there is a chance that a subclass will be added later. 1094 if (!ik->is_final()) { 1095 phase->C->dependencies()->assert_leaf_type(ik); 1096 } 1097 } 1098 1099 // Bypass the dependent load, and compare directly 1100 this->set_req(1,ldk2); 1101 1102 return this; 1103 } 1104 1105 //============================================================================= 1106 //------------------------------sub-------------------------------------------- 1107 // Simplify an CmpN (compare 2 pointers) node, based on local information. 1108 // If both inputs are constants, compare them. 1109 const Type *CmpNNode::sub( const Type *t1, const Type *t2 ) const { 1110 const TypePtr *r0 = t1->make_ptr(); // Handy access 1111 const TypePtr *r1 = t2->make_ptr(); 1112 1113 // Undefined inputs makes for an undefined result 1114 if ((r0 == NULL) || (r1 == NULL) || 1115 TypePtr::above_centerline(r0->_ptr) || 1116 TypePtr::above_centerline(r1->_ptr)) { 1117 return Type::TOP; 1118 } 1119 if (r0 == r1 && r0->singleton()) { 1120 // Equal pointer constants (klasses, nulls, etc.) 1121 return TypeInt::CC_EQ; 1122 } 1123 1124 // See if it is 2 unrelated classes. 1125 const TypeOopPtr* p0 = r0->isa_oopptr(); 1126 const TypeOopPtr* p1 = r1->isa_oopptr(); 1127 if (p0 && p1) { 1128 ciKlass* klass0 = p0->klass(); 1129 bool xklass0 = p0->klass_is_exact(); 1130 ciKlass* klass1 = p1->klass(); 1131 bool xklass1 = p1->klass_is_exact(); 1132 int kps = (p0->isa_klassptr()?1:0) + (p1->isa_klassptr()?1:0); 1133 if (klass0 && klass1 && 1134 kps != 1 && // both or neither are klass pointers 1135 !klass0->is_interface() && // do not trust interfaces 1136 !klass1->is_interface()) { 1137 bool unrelated_classes = false; 1138 // See if neither subclasses the other, or if the class on top 1139 // is precise. In either of these cases, the compare is known 1140 // to fail if at least one of the pointers is provably not null. 1141 if (klass0->equals(klass1)) { // if types are unequal but klasses are equal 1142 // Do nothing; we know nothing for imprecise types 1143 } else if (klass0->is_subtype_of(klass1)) { 1144 // If klass1's type is PRECISE, then classes are unrelated. 1145 unrelated_classes = xklass1; 1146 } else if (klass1->is_subtype_of(klass0)) { 1147 // If klass0's type is PRECISE, then classes are unrelated. 1148 unrelated_classes = xklass0; 1149 } else { // Neither subtypes the other 1150 unrelated_classes = true; 1151 } 1152 if (unrelated_classes) { 1153 // The oops classes are known to be unrelated. If the joined PTRs of 1154 // two oops is not Null and not Bottom, then we are sure that one 1155 // of the two oops is non-null, and the comparison will always fail. 1156 TypePtr::PTR jp = r0->join_ptr(r1->_ptr); 1157 if (jp != TypePtr::Null && jp != TypePtr::BotPTR) { 1158 return TypeInt::CC_GT; 1159 } 1160 } 1161 } 1162 } 1163 1164 // Known constants can be compared exactly 1165 // Null can be distinguished from any NotNull pointers 1166 // Unknown inputs makes an unknown result 1167 if( r0->singleton() ) { 1168 intptr_t bits0 = r0->get_con(); 1169 if( r1->singleton() ) 1170 return bits0 == r1->get_con() ? TypeInt::CC_EQ : TypeInt::CC_GT; 1171 return ( r1->_ptr == TypePtr::NotNull && bits0==0 ) ? TypeInt::CC_GT : TypeInt::CC; 1172 } else if( r1->singleton() ) { 1173 intptr_t bits1 = r1->get_con(); 1174 return ( r0->_ptr == TypePtr::NotNull && bits1==0 ) ? TypeInt::CC_GT : TypeInt::CC; 1175 } else 1176 return TypeInt::CC; 1177 } 1178 1179 //------------------------------Ideal------------------------------------------ 1180 Node *CmpNNode::Ideal( PhaseGVN *phase, bool can_reshape ) { 1181 return NULL; 1182 } 1183 1184 //============================================================================= 1185 //------------------------------Value------------------------------------------ 1186 // Simplify an CmpF (compare 2 floats ) node, based on local information. 1187 // If both inputs are constants, compare them. 1188 const Type* CmpFNode::Value(PhaseGVN* phase) const { 1189 const Node* in1 = in(1); 1190 const Node* in2 = in(2); 1191 // Either input is TOP ==> the result is TOP 1192 const Type* t1 = (in1 == this) ? Type::TOP : phase->type(in1); 1193 if( t1 == Type::TOP ) return Type::TOP; 1194 const Type* t2 = (in2 == this) ? Type::TOP : phase->type(in2); 1195 if( t2 == Type::TOP ) return Type::TOP; 1196 1197 // Not constants? Don't know squat - even if they are the same 1198 // value! If they are NaN's they compare to LT instead of EQ. 1199 const TypeF *tf1 = t1->isa_float_constant(); 1200 const TypeF *tf2 = t2->isa_float_constant(); 1201 if( !tf1 || !tf2 ) return TypeInt::CC; 1202 1203 // This implements the Java bytecode fcmpl, so unordered returns -1. 1204 if( tf1->is_nan() || tf2->is_nan() ) 1205 return TypeInt::CC_LT; 1206 1207 if( tf1->_f < tf2->_f ) return TypeInt::CC_LT; 1208 if( tf1->_f > tf2->_f ) return TypeInt::CC_GT; 1209 assert( tf1->_f == tf2->_f, "do not understand FP behavior" ); 1210 return TypeInt::CC_EQ; 1211 } 1212 1213 1214 //============================================================================= 1215 //------------------------------Value------------------------------------------ 1216 // Simplify an CmpD (compare 2 doubles ) node, based on local information. 1217 // If both inputs are constants, compare them. 1218 const Type* CmpDNode::Value(PhaseGVN* phase) const { 1219 const Node* in1 = in(1); 1220 const Node* in2 = in(2); 1221 // Either input is TOP ==> the result is TOP 1222 const Type* t1 = (in1 == this) ? Type::TOP : phase->type(in1); 1223 if( t1 == Type::TOP ) return Type::TOP; 1224 const Type* t2 = (in2 == this) ? Type::TOP : phase->type(in2); 1225 if( t2 == Type::TOP ) return Type::TOP; 1226 1227 // Not constants? Don't know squat - even if they are the same 1228 // value! If they are NaN's they compare to LT instead of EQ. 1229 const TypeD *td1 = t1->isa_double_constant(); 1230 const TypeD *td2 = t2->isa_double_constant(); 1231 if( !td1 || !td2 ) return TypeInt::CC; 1232 1233 // This implements the Java bytecode dcmpl, so unordered returns -1. 1234 if( td1->is_nan() || td2->is_nan() ) 1235 return TypeInt::CC_LT; 1236 1237 if( td1->_d < td2->_d ) return TypeInt::CC_LT; 1238 if( td1->_d > td2->_d ) return TypeInt::CC_GT; 1239 assert( td1->_d == td2->_d, "do not understand FP behavior" ); 1240 return TypeInt::CC_EQ; 1241 } 1242 1243 //------------------------------Ideal------------------------------------------ 1244 Node *CmpDNode::Ideal(PhaseGVN *phase, bool can_reshape){ 1245 // Check if we can change this to a CmpF and remove a ConvD2F operation. 1246 // Change (CMPD (F2D (float)) (ConD value)) 1247 // To (CMPF (float) (ConF value)) 1248 // Valid when 'value' does not lose precision as a float. 1249 // Benefits: eliminates conversion, does not require 24-bit mode 1250 1251 // NaNs prevent commuting operands. This transform works regardless of the 1252 // order of ConD and ConvF2D inputs by preserving the original order. 1253 int idx_f2d = 1; // ConvF2D on left side? 1254 if( in(idx_f2d)->Opcode() != Op_ConvF2D ) 1255 idx_f2d = 2; // No, swap to check for reversed args 1256 int idx_con = 3-idx_f2d; // Check for the constant on other input 1257 1258 if( ConvertCmpD2CmpF && 1259 in(idx_f2d)->Opcode() == Op_ConvF2D && 1260 in(idx_con)->Opcode() == Op_ConD ) { 1261 const TypeD *t2 = in(idx_con)->bottom_type()->is_double_constant(); 1262 double t2_value_as_double = t2->_d; 1263 float t2_value_as_float = (float)t2_value_as_double; 1264 if( t2_value_as_double == (double)t2_value_as_float ) { 1265 // Test value can be represented as a float 1266 // Eliminate the conversion to double and create new comparison 1267 Node *new_in1 = in(idx_f2d)->in(1); 1268 Node *new_in2 = phase->makecon( TypeF::make(t2_value_as_float) ); 1269 if( idx_f2d != 1 ) { // Must flip args to match original order 1270 Node *tmp = new_in1; 1271 new_in1 = new_in2; 1272 new_in2 = tmp; 1273 } 1274 CmpFNode *new_cmp = (Opcode() == Op_CmpD3) 1275 ? new CmpF3Node( new_in1, new_in2 ) 1276 : new CmpFNode ( new_in1, new_in2 ) ; 1277 return new_cmp; // Changed to CmpFNode 1278 } 1279 // Testing value required the precision of a double 1280 } 1281 return NULL; // No change 1282 } 1283 1284 1285 //============================================================================= 1286 //------------------------------cc2logical------------------------------------- 1287 // Convert a condition code type to a logical type 1288 const Type *BoolTest::cc2logical( const Type *CC ) const { 1289 if( CC == Type::TOP ) return Type::TOP; 1290 if( CC->base() != Type::Int ) return TypeInt::BOOL; // Bottom or worse 1291 const TypeInt *ti = CC->is_int(); 1292 if( ti->is_con() ) { // Only 1 kind of condition codes set? 1293 // Match low order 2 bits 1294 int tmp = ((ti->get_con()&3) == (_test&3)) ? 1 : 0; 1295 if( _test & 4 ) tmp = 1-tmp; // Optionally complement result 1296 return TypeInt::make(tmp); // Boolean result 1297 } 1298 1299 if( CC == TypeInt::CC_GE ) { 1300 if( _test == ge ) return TypeInt::ONE; 1301 if( _test == lt ) return TypeInt::ZERO; 1302 } 1303 if( CC == TypeInt::CC_LE ) { 1304 if( _test == le ) return TypeInt::ONE; 1305 if( _test == gt ) return TypeInt::ZERO; 1306 } 1307 1308 return TypeInt::BOOL; 1309 } 1310 1311 //------------------------------dump_spec------------------------------------- 1312 // Print special per-node info 1313 void BoolTest::dump_on(outputStream *st) const { 1314 const char *msg[] = {"eq","gt","of","lt","ne","le","nof","ge"}; 1315 st->print("%s", msg[_test]); 1316 } 1317 1318 // Returns the logical AND of two tests (or 'never' if both tests can never be true). 1319 // For example, a test for 'le' followed by a test for 'lt' is equivalent with 'lt'. 1320 BoolTest::mask BoolTest::merge(BoolTest other) const { 1321 const mask res[illegal+1][illegal+1] = { 1322 // eq, gt, of, lt, ne, le, nof, ge, never, illegal 1323 {eq, never, illegal, never, never, eq, illegal, eq, never, illegal}, // eq 1324 {never, gt, illegal, never, gt, never, illegal, gt, never, illegal}, // gt 1325 {illegal, illegal, illegal, illegal, illegal, illegal, illegal, illegal, never, illegal}, // of 1326 {never, never, illegal, lt, lt, lt, illegal, never, never, illegal}, // lt 1327 {never, gt, illegal, lt, ne, lt, illegal, gt, never, illegal}, // ne 1328 {eq, never, illegal, lt, lt, le, illegal, eq, never, illegal}, // le 1329 {illegal, illegal, illegal, illegal, illegal, illegal, illegal, illegal, never, illegal}, // nof 1330 {eq, gt, illegal, never, gt, eq, illegal, ge, never, illegal}, // ge 1331 {never, never, never, never, never, never, never, never, never, illegal}, // never 1332 {illegal, illegal, illegal, illegal, illegal, illegal, illegal, illegal, illegal, illegal}}; // illegal 1333 return res[_test][other._test]; 1334 } 1335 1336 //============================================================================= 1337 uint BoolNode::hash() const { return (Node::hash() << 3)|(_test._test+1); } 1338 uint BoolNode::size_of() const { return sizeof(BoolNode); } 1339 1340 //------------------------------operator==------------------------------------- 1341 bool BoolNode::cmp( const Node &n ) const { 1342 const BoolNode *b = (const BoolNode *)&n; // Cast up 1343 return (_test._test == b->_test._test); 1344 } 1345 1346 //-------------------------------make_predicate-------------------------------- 1347 Node* BoolNode::make_predicate(Node* test_value, PhaseGVN* phase) { 1348 if (test_value->is_Con()) return test_value; 1349 if (test_value->is_Bool()) return test_value; 1350 if (test_value->is_CMove() && 1351 test_value->in(CMoveNode::Condition)->is_Bool()) { 1352 BoolNode* bol = test_value->in(CMoveNode::Condition)->as_Bool(); 1353 const Type* ftype = phase->type(test_value->in(CMoveNode::IfFalse)); 1354 const Type* ttype = phase->type(test_value->in(CMoveNode::IfTrue)); 1355 if (ftype == TypeInt::ZERO && !TypeInt::ZERO->higher_equal(ttype)) { 1356 return bol; 1357 } else if (ttype == TypeInt::ZERO && !TypeInt::ZERO->higher_equal(ftype)) { 1358 return phase->transform( bol->negate(phase) ); 1359 } 1360 // Else fall through. The CMove gets in the way of the test. 1361 // It should be the case that make_predicate(bol->as_int_value()) == bol. 1362 } 1363 Node* cmp = new CmpINode(test_value, phase->intcon(0)); 1364 cmp = phase->transform(cmp); 1365 Node* bol = new BoolNode(cmp, BoolTest::ne); 1366 return phase->transform(bol); 1367 } 1368 1369 //--------------------------------as_int_value--------------------------------- 1370 Node* BoolNode::as_int_value(PhaseGVN* phase) { 1371 // Inverse to make_predicate. The CMove probably boils down to a Conv2B. 1372 Node* cmov = CMoveNode::make(NULL, this, 1373 phase->intcon(0), phase->intcon(1), 1374 TypeInt::BOOL); 1375 return phase->transform(cmov); 1376 } 1377 1378 //----------------------------------negate------------------------------------- 1379 BoolNode* BoolNode::negate(PhaseGVN* phase) { 1380 return new BoolNode(in(1), _test.negate()); 1381 } 1382 1383 // Change "bool eq/ne (cmp (add/sub A B) C)" into false/true if add/sub 1384 // overflows and we can prove that C is not in the two resulting ranges. 1385 // This optimization is similar to the one performed by CmpUNode::Value(). 1386 Node* BoolNode::fold_cmpI(PhaseGVN* phase, SubNode* cmp, Node* cmp1, int cmp_op, 1387 int cmp1_op, const TypeInt* cmp2_type) { 1388 // Only optimize eq/ne integer comparison of add/sub 1389 if((_test._test == BoolTest::eq || _test._test == BoolTest::ne) && 1390 (cmp_op == Op_CmpI) && (cmp1_op == Op_AddI || cmp1_op == Op_SubI)) { 1391 // Skip cases were inputs of add/sub are not integers or of bottom type 1392 const TypeInt* r0 = phase->type(cmp1->in(1))->isa_int(); 1393 const TypeInt* r1 = phase->type(cmp1->in(2))->isa_int(); 1394 if ((r0 != NULL) && (r0 != TypeInt::INT) && 1395 (r1 != NULL) && (r1 != TypeInt::INT) && 1396 (cmp2_type != TypeInt::INT)) { 1397 // Compute exact (long) type range of add/sub result 1398 jlong lo_long = r0->_lo; 1399 jlong hi_long = r0->_hi; 1400 if (cmp1_op == Op_AddI) { 1401 lo_long += r1->_lo; 1402 hi_long += r1->_hi; 1403 } else { 1404 lo_long -= r1->_hi; 1405 hi_long -= r1->_lo; 1406 } 1407 // Check for over-/underflow by casting to integer 1408 int lo_int = (int)lo_long; 1409 int hi_int = (int)hi_long; 1410 bool underflow = lo_long != (jlong)lo_int; 1411 bool overflow = hi_long != (jlong)hi_int; 1412 if ((underflow != overflow) && (hi_int < lo_int)) { 1413 // Overflow on one boundary, compute resulting type ranges: 1414 // tr1 [MIN_INT, hi_int] and tr2 [lo_int, MAX_INT] 1415 int w = MAX2(r0->_widen, r1->_widen); // _widen does not matter here 1416 const TypeInt* tr1 = TypeInt::make(min_jint, hi_int, w); 1417 const TypeInt* tr2 = TypeInt::make(lo_int, max_jint, w); 1418 // Compare second input of cmp to both type ranges 1419 const Type* sub_tr1 = cmp->sub(tr1, cmp2_type); 1420 const Type* sub_tr2 = cmp->sub(tr2, cmp2_type); 1421 if (sub_tr1 == TypeInt::CC_LT && sub_tr2 == TypeInt::CC_GT) { 1422 // The result of the add/sub will never equal cmp2. Replace BoolNode 1423 // by false (0) if it tests for equality and by true (1) otherwise. 1424 return ConINode::make((_test._test == BoolTest::eq) ? 0 : 1); 1425 } 1426 } 1427 } 1428 } 1429 return NULL; 1430 } 1431 1432 static bool is_counted_loop_cmp(Node *cmp) { 1433 Node *n = cmp->in(1)->in(1); 1434 return n != NULL && 1435 n->is_Phi() && 1436 n->in(0) != NULL && 1437 n->in(0)->is_CountedLoop() && 1438 n->in(0)->as_CountedLoop()->phi() == n; 1439 } 1440 1441 //------------------------------Ideal------------------------------------------ 1442 Node *BoolNode::Ideal(PhaseGVN *phase, bool can_reshape) { 1443 // Change "bool tst (cmp con x)" into "bool ~tst (cmp x con)". 1444 // This moves the constant to the right. Helps value-numbering. 1445 Node *cmp = in(1); 1446 if( !cmp->is_Sub() ) return NULL; 1447 int cop = cmp->Opcode(); 1448 if( cop == Op_FastLock || cop == Op_FastUnlock) return NULL; 1449 Node *cmp1 = cmp->in(1); 1450 Node *cmp2 = cmp->in(2); 1451 if( !cmp1 ) return NULL; 1452 1453 if (_test._test == BoolTest::overflow || _test._test == BoolTest::no_overflow) { 1454 return NULL; 1455 } 1456 1457 // Constant on left? 1458 Node *con = cmp1; 1459 uint op2 = cmp2->Opcode(); 1460 // Move constants to the right of compare's to canonicalize. 1461 // Do not muck with Opaque1 nodes, as this indicates a loop 1462 // guard that cannot change shape. 1463 if( con->is_Con() && !cmp2->is_Con() && op2 != Op_Opaque1 && 1464 // Because of NaN's, CmpD and CmpF are not commutative 1465 cop != Op_CmpD && cop != Op_CmpF && 1466 // Protect against swapping inputs to a compare when it is used by a 1467 // counted loop exit, which requires maintaining the loop-limit as in(2) 1468 !is_counted_loop_exit_test() ) { 1469 // Ok, commute the constant to the right of the cmp node. 1470 // Clone the Node, getting a new Node of the same class 1471 cmp = cmp->clone(); 1472 // Swap inputs to the clone 1473 cmp->swap_edges(1, 2); 1474 cmp = phase->transform( cmp ); 1475 return new BoolNode( cmp, _test.commute() ); 1476 } 1477 1478 // Change "bool eq/ne (cmp (xor X 1) 0)" into "bool ne/eq (cmp X 0)". 1479 // The XOR-1 is an idiom used to flip the sense of a bool. We flip the 1480 // test instead. 1481 int cmp1_op = cmp1->Opcode(); 1482 const TypeInt* cmp2_type = phase->type(cmp2)->isa_int(); 1483 if (cmp2_type == NULL) return NULL; 1484 Node* j_xor = cmp1; 1485 if( cmp2_type == TypeInt::ZERO && 1486 cmp1_op == Op_XorI && 1487 j_xor->in(1) != j_xor && // An xor of itself is dead 1488 phase->type( j_xor->in(1) ) == TypeInt::BOOL && 1489 phase->type( j_xor->in(2) ) == TypeInt::ONE && 1490 (_test._test == BoolTest::eq || 1491 _test._test == BoolTest::ne) ) { 1492 Node *ncmp = phase->transform(new CmpINode(j_xor->in(1),cmp2)); 1493 return new BoolNode( ncmp, _test.negate() ); 1494 } 1495 1496 // Change ((x & m) u<= m) or ((m & x) u<= m) to always true 1497 // Same with ((x & m) u< m+1) and ((m & x) u< m+1) 1498 if (cop == Op_CmpU && 1499 cmp1_op == Op_AndI) { 1500 Node* bound = NULL; 1501 if (_test._test == BoolTest::le) { 1502 bound = cmp2; 1503 } else if (_test._test == BoolTest::lt && 1504 cmp2->Opcode() == Op_AddI && 1505 cmp2->in(2)->find_int_con(0) == 1) { 1506 bound = cmp2->in(1); 1507 } 1508 if (cmp1->in(2) == bound || cmp1->in(1) == bound) { 1509 return ConINode::make(1); 1510 } 1511 } 1512 1513 // Change ((x & (m - 1)) u< m) into (m > 0) 1514 // This is the off-by-one variant of the above 1515 if (cop == Op_CmpU && 1516 _test._test == BoolTest::lt && 1517 cmp1_op == Op_AndI) { 1518 Node* l = cmp1->in(1); 1519 Node* r = cmp1->in(2); 1520 for (int repeat = 0; repeat < 2; repeat++) { 1521 bool match = r->Opcode() == Op_AddI && r->in(2)->find_int_con(0) == -1 && 1522 r->in(1) == cmp2; 1523 if (match) { 1524 // arraylength known to be non-negative, so a (arraylength != 0) is sufficient, 1525 // but to be compatible with the array range check pattern, use (arraylength u> 0) 1526 Node* ncmp = cmp2->Opcode() == Op_LoadRange 1527 ? phase->transform(new CmpUNode(cmp2, phase->intcon(0))) 1528 : phase->transform(new CmpINode(cmp2, phase->intcon(0))); 1529 return new BoolNode(ncmp, BoolTest::gt); 1530 } else { 1531 // commute and try again 1532 l = cmp1->in(2); 1533 r = cmp1->in(1); 1534 } 1535 } 1536 } 1537 1538 // Change x u< 1 or x u<= 0 to x == 0 1539 if (cop == Op_CmpU && 1540 cmp1_op != Op_LoadRange && 1541 ((_test._test == BoolTest::lt && 1542 cmp2->find_int_con(-1) == 1) || 1543 (_test._test == BoolTest::le && 1544 cmp2->find_int_con(-1) == 0))) { 1545 Node* ncmp = phase->transform(new CmpINode(cmp1, phase->intcon(0))); 1546 return new BoolNode(ncmp, BoolTest::eq); 1547 } 1548 1549 // Change (arraylength <= 0) or (arraylength == 0) 1550 // into (arraylength u<= 0) 1551 // Also change (arraylength != 0) into (arraylength u> 0) 1552 // The latter version matches the code pattern generated for 1553 // array range checks, which will more likely be optimized later. 1554 if (cop == Op_CmpI && 1555 cmp1_op == Op_LoadRange && 1556 cmp2->find_int_con(-1) == 0) { 1557 if (_test._test == BoolTest::le || _test._test == BoolTest::eq) { 1558 Node* ncmp = phase->transform(new CmpUNode(cmp1, cmp2)); 1559 return new BoolNode(ncmp, BoolTest::le); 1560 } else if (_test._test == BoolTest::ne) { 1561 Node* ncmp = phase->transform(new CmpUNode(cmp1, cmp2)); 1562 return new BoolNode(ncmp, BoolTest::gt); 1563 } 1564 } 1565 1566 // Change "bool eq/ne (cmp (Conv2B X) 0)" into "bool eq/ne (cmp X 0)". 1567 // This is a standard idiom for branching on a boolean value. 1568 Node *c2b = cmp1; 1569 if( cmp2_type == TypeInt::ZERO && 1570 cmp1_op == Op_Conv2B && 1571 (_test._test == BoolTest::eq || 1572 _test._test == BoolTest::ne) ) { 1573 Node *ncmp = phase->transform(phase->type(c2b->in(1))->isa_int() 1574 ? (Node*)new CmpINode(c2b->in(1),cmp2) 1575 : (Node*)new CmpPNode(c2b->in(1),phase->makecon(TypePtr::NULL_PTR)) 1576 ); 1577 return new BoolNode( ncmp, _test._test ); 1578 } 1579 1580 // Comparing a SubI against a zero is equal to comparing the SubI 1581 // arguments directly. This only works for eq and ne comparisons 1582 // due to possible integer overflow. 1583 if ((_test._test == BoolTest::eq || _test._test == BoolTest::ne) && 1584 (cop == Op_CmpI) && 1585 (cmp1_op == Op_SubI) && 1586 ( cmp2_type == TypeInt::ZERO ) ) { 1587 Node *ncmp = phase->transform( new CmpINode(cmp1->in(1),cmp1->in(2))); 1588 return new BoolNode( ncmp, _test._test ); 1589 } 1590 1591 // Same as above but with and AddI of a constant 1592 if ((_test._test == BoolTest::eq || _test._test == BoolTest::ne) && 1593 cop == Op_CmpI && 1594 cmp1_op == Op_AddI && 1595 cmp1->in(2) != NULL && 1596 phase->type(cmp1->in(2))->isa_int() && 1597 phase->type(cmp1->in(2))->is_int()->is_con() && 1598 cmp2_type == TypeInt::ZERO && 1599 !is_counted_loop_cmp(cmp) // modifying the exit test of a counted loop messes the counted loop shape 1600 ) { 1601 const TypeInt* cmp1_in2 = phase->type(cmp1->in(2))->is_int(); 1602 Node *ncmp = phase->transform( new CmpINode(cmp1->in(1),phase->intcon(-cmp1_in2->_hi))); 1603 return new BoolNode( ncmp, _test._test ); 1604 } 1605 1606 // Change "bool eq/ne (cmp (phi (X -X) 0))" into "bool eq/ne (cmp X 0)" 1607 // since zero check of conditional negation of an integer is equal to 1608 // zero check of the integer directly. 1609 if ((_test._test == BoolTest::eq || _test._test == BoolTest::ne) && 1610 (cop == Op_CmpI) && 1611 (cmp2_type == TypeInt::ZERO) && 1612 (cmp1_op == Op_Phi)) { 1613 // There should be a diamond phi with true path at index 1 or 2 1614 PhiNode *phi = cmp1->as_Phi(); 1615 int idx_true = phi->is_diamond_phi(); 1616 if (idx_true != 0) { 1617 // True input is in(idx_true) while false input is in(3 - idx_true) 1618 Node *tin = phi->in(idx_true); 1619 Node *fin = phi->in(3 - idx_true); 1620 if ((tin->Opcode() == Op_SubI) && 1621 (phase->type(tin->in(1)) == TypeInt::ZERO) && 1622 (tin->in(2) == fin)) { 1623 // Found conditional negation at true path, create a new CmpINode without that 1624 Node *ncmp = phase->transform(new CmpINode(fin, cmp2)); 1625 return new BoolNode(ncmp, _test._test); 1626 } 1627 if ((fin->Opcode() == Op_SubI) && 1628 (phase->type(fin->in(1)) == TypeInt::ZERO) && 1629 (fin->in(2) == tin)) { 1630 // Found conditional negation at false path, create a new CmpINode without that 1631 Node *ncmp = phase->transform(new CmpINode(tin, cmp2)); 1632 return new BoolNode(ncmp, _test._test); 1633 } 1634 } 1635 } 1636 1637 // Change (-A vs 0) into (A vs 0) by commuting the test. Disallow in the 1638 // most general case because negating 0x80000000 does nothing. Needed for 1639 // the CmpF3/SubI/CmpI idiom. 1640 if( cop == Op_CmpI && 1641 cmp1_op == Op_SubI && 1642 cmp2_type == TypeInt::ZERO && 1643 phase->type( cmp1->in(1) ) == TypeInt::ZERO && 1644 phase->type( cmp1->in(2) )->higher_equal(TypeInt::SYMINT) ) { 1645 Node *ncmp = phase->transform( new CmpINode(cmp1->in(2),cmp2)); 1646 return new BoolNode( ncmp, _test.commute() ); 1647 } 1648 1649 // Try to optimize signed integer comparison 1650 return fold_cmpI(phase, cmp->as_Sub(), cmp1, cop, cmp1_op, cmp2_type); 1651 1652 // The transformation below is not valid for either signed or unsigned 1653 // comparisons due to wraparound concerns at MAX_VALUE and MIN_VALUE. 1654 // This transformation can be resurrected when we are able to 1655 // make inferences about the range of values being subtracted from 1656 // (or added to) relative to the wraparound point. 1657 // 1658 // // Remove +/-1's if possible. 1659 // // "X <= Y-1" becomes "X < Y" 1660 // // "X+1 <= Y" becomes "X < Y" 1661 // // "X < Y+1" becomes "X <= Y" 1662 // // "X-1 < Y" becomes "X <= Y" 1663 // // Do not this to compares off of the counted-loop-end. These guys are 1664 // // checking the trip counter and they want to use the post-incremented 1665 // // counter. If they use the PRE-incremented counter, then the counter has 1666 // // to be incremented in a private block on a loop backedge. 1667 // if( du && du->cnt(this) && du->out(this)[0]->Opcode() == Op_CountedLoopEnd ) 1668 // return NULL; 1669 // #ifndef PRODUCT 1670 // // Do not do this in a wash GVN pass during verification. 1671 // // Gets triggered by too many simple optimizations to be bothered with 1672 // // re-trying it again and again. 1673 // if( !phase->allow_progress() ) return NULL; 1674 // #endif 1675 // // Not valid for unsigned compare because of corner cases in involving zero. 1676 // // For example, replacing "X-1 <u Y" with "X <=u Y" fails to throw an 1677 // // exception in case X is 0 (because 0-1 turns into 4billion unsigned but 1678 // // "0 <=u Y" is always true). 1679 // if( cmp->Opcode() == Op_CmpU ) return NULL; 1680 // int cmp2_op = cmp2->Opcode(); 1681 // if( _test._test == BoolTest::le ) { 1682 // if( cmp1_op == Op_AddI && 1683 // phase->type( cmp1->in(2) ) == TypeInt::ONE ) 1684 // return clone_cmp( cmp, cmp1->in(1), cmp2, phase, BoolTest::lt ); 1685 // else if( cmp2_op == Op_AddI && 1686 // phase->type( cmp2->in(2) ) == TypeInt::MINUS_1 ) 1687 // return clone_cmp( cmp, cmp1, cmp2->in(1), phase, BoolTest::lt ); 1688 // } else if( _test._test == BoolTest::lt ) { 1689 // if( cmp1_op == Op_AddI && 1690 // phase->type( cmp1->in(2) ) == TypeInt::MINUS_1 ) 1691 // return clone_cmp( cmp, cmp1->in(1), cmp2, phase, BoolTest::le ); 1692 // else if( cmp2_op == Op_AddI && 1693 // phase->type( cmp2->in(2) ) == TypeInt::ONE ) 1694 // return clone_cmp( cmp, cmp1, cmp2->in(1), phase, BoolTest::le ); 1695 // } 1696 } 1697 1698 //------------------------------Value------------------------------------------ 1699 // Simplify a Bool (convert condition codes to boolean (1 or 0)) node, 1700 // based on local information. If the input is constant, do it. 1701 const Type* BoolNode::Value(PhaseGVN* phase) const { 1702 return _test.cc2logical( phase->type( in(1) ) ); 1703 } 1704 1705 #ifndef PRODUCT 1706 //------------------------------dump_spec-------------------------------------- 1707 // Dump special per-node info 1708 void BoolNode::dump_spec(outputStream *st) const { 1709 st->print("["); 1710 _test.dump_on(st); 1711 st->print("]"); 1712 } 1713 1714 //-------------------------------related--------------------------------------- 1715 // A BoolNode's related nodes are all of its data inputs, and all of its 1716 // outputs until control nodes are hit, which are included. In compact 1717 // representation, inputs till level 3 and immediate outputs are included. 1718 void BoolNode::related(GrowableArray<Node*> *in_rel, GrowableArray<Node*> *out_rel, bool compact) const { 1719 if (compact) { 1720 this->collect_nodes(in_rel, 3, false, true); 1721 this->collect_nodes(out_rel, -1, false, false); 1722 } else { 1723 this->collect_nodes_in_all_data(in_rel, false); 1724 this->collect_nodes_out_all_ctrl_boundary(out_rel); 1725 } 1726 } 1727 #endif 1728 1729 //----------------------is_counted_loop_exit_test------------------------------ 1730 // Returns true if node is used by a counted loop node. 1731 bool BoolNode::is_counted_loop_exit_test() { 1732 for( DUIterator_Fast imax, i = fast_outs(imax); i < imax; i++ ) { 1733 Node* use = fast_out(i); 1734 if (use->is_CountedLoopEnd()) { 1735 return true; 1736 } 1737 } 1738 return false; 1739 } 1740 1741 //============================================================================= 1742 //------------------------------Value------------------------------------------ 1743 // Compute sqrt 1744 const Type* SqrtDNode::Value(PhaseGVN* phase) const { 1745 const Type *t1 = phase->type( in(1) ); 1746 if( t1 == Type::TOP ) return Type::TOP; 1747 if( t1->base() != Type::DoubleCon ) return Type::DOUBLE; 1748 double d = t1->getd(); 1749 if( d < 0.0 ) return Type::DOUBLE; 1750 return TypeD::make( sqrt( d ) ); 1751 } 1752 1753 const Type* SqrtFNode::Value(PhaseGVN* phase) const { 1754 const Type *t1 = phase->type( in(1) ); 1755 if( t1 == Type::TOP ) return Type::TOP; 1756 if( t1->base() != Type::FloatCon ) return Type::FLOAT; 1757 float f = t1->getf(); 1758 if( f < 0.0f ) return Type::FLOAT; 1759 return TypeF::make( (float)sqrt( (double)f ) ); 1760 }