1 /* 2 * Copyright (c) 1997, 2022, 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/inlinetypenode.hpp" 34 #include "opto/loopnode.hpp" 35 #include "opto/matcher.hpp" 36 #include "opto/movenode.hpp" 37 #include "opto/mulnode.hpp" 38 #include "opto/opcodes.hpp" 39 #include "opto/phaseX.hpp" 40 #include "opto/subnode.hpp" 41 #include "runtime/sharedRuntime.hpp" 42 43 // Portions of code courtesy of Clifford Click 44 45 // Optimization - Graph Style 46 47 #include "math.h" 48 49 //============================================================================= 50 //------------------------------Identity--------------------------------------- 51 // If right input is a constant 0, return the left input. 52 Node* SubNode::Identity(PhaseGVN* phase) { 53 assert(in(1) != this, "Must already have called Value"); 54 assert(in(2) != this, "Must already have called Value"); 55 56 // Remove double negation 57 const Type *zero = add_id(); 58 if( phase->type( in(1) )->higher_equal( zero ) && 59 in(2)->Opcode() == Opcode() && 60 phase->type( in(2)->in(1) )->higher_equal( zero ) ) { 61 return in(2)->in(2); 62 } 63 64 // Convert "(X+Y) - Y" into X and "(X+Y) - X" into Y 65 if (in(1)->Opcode() == Op_AddI || in(1)->Opcode() == Op_AddL) { 66 if (in(1)->in(2) == in(2)) { 67 return in(1)->in(1); 68 } 69 if (in(1)->in(1) == in(2)) { 70 return in(1)->in(2); 71 } 72 73 // Also catch: "(X + Opaque2(Y)) - Y". In this case, 'Y' is a loop-varying 74 // trip counter and X is likely to be loop-invariant (that's how O2 Nodes 75 // are originally used, although the optimizer sometimes jiggers things). 76 // This folding through an O2 removes a loop-exit use of a loop-varying 77 // value and generally lowers register pressure in and around the loop. 78 if (in(1)->in(2)->Opcode() == Op_Opaque2 && in(1)->in(2)->in(1) == in(2)) { 79 return in(1)->in(1); 80 } 81 } 82 83 return ( phase->type( in(2) )->higher_equal( zero ) ) ? in(1) : this; 84 } 85 86 //------------------------------Value------------------------------------------ 87 // A subtract node differences it's two inputs. 88 const Type* SubNode::Value_common(PhaseTransform *phase) const { 89 const Node* in1 = in(1); 90 const Node* in2 = in(2); 91 // Either input is TOP ==> the result is TOP 92 const Type* t1 = (in1 == this) ? Type::TOP : phase->type(in1); 93 if( t1 == Type::TOP ) return Type::TOP; 94 const Type* t2 = (in2 == this) ? Type::TOP : phase->type(in2); 95 if( t2 == Type::TOP ) return Type::TOP; 96 97 // Not correct for SubFnode and AddFNode (must check for infinity) 98 // Equal? Subtract is zero 99 if (in1->eqv_uncast(in2)) return add_id(); 100 101 // Either input is BOTTOM ==> the result is the local BOTTOM 102 if( t1 == Type::BOTTOM || t2 == Type::BOTTOM ) 103 return bottom_type(); 104 105 return NULL; 106 } 107 108 const Type* SubNode::Value(PhaseGVN* phase) const { 109 const Type* t = Value_common(phase); 110 if (t != NULL) { 111 return t; 112 } 113 const Type* t1 = phase->type(in(1)); 114 const Type* t2 = phase->type(in(2)); 115 return sub(t1,t2); // Local flavor of type subtraction 116 117 } 118 119 SubNode* SubNode::make(Node* in1, Node* in2, BasicType bt) { 120 switch (bt) { 121 case T_INT: 122 return new SubINode(in1, in2); 123 case T_LONG: 124 return new SubLNode(in1, in2); 125 default: 126 fatal("Not implemented for %s", type2name(bt)); 127 } 128 return NULL; 129 } 130 131 //============================================================================= 132 //------------------------------Helper function-------------------------------- 133 134 static bool is_cloop_increment(Node* inc) { 135 precond(inc->Opcode() == Op_AddI || inc->Opcode() == Op_AddL); 136 137 if (!inc->in(1)->is_Phi()) { 138 return false; 139 } 140 const PhiNode* phi = inc->in(1)->as_Phi(); 141 142 if (!phi->region()->is_CountedLoop()) { 143 return false; 144 } 145 146 return inc == phi->region()->as_CountedLoop()->incr(); 147 } 148 149 // Given the expression '(x + C) - v', or 150 // 'v - (x + C)', we examine nodes '+' and 'v': 151 // 152 // 1. Do not convert if '+' is a counted-loop increment, because the '-' is 153 // loop invariant and converting extends the live-range of 'x' to overlap 154 // with the '+', forcing another register to be used in the loop. 155 // 156 // 2. Do not convert if 'v' is a counted-loop induction variable, because 157 // 'x' might be invariant. 158 // 159 static bool ok_to_convert(Node* inc, Node* var) { 160 return !(is_cloop_increment(inc) || var->is_cloop_ind_var()); 161 } 162 163 //------------------------------Ideal------------------------------------------ 164 Node *SubINode::Ideal(PhaseGVN *phase, bool can_reshape){ 165 Node *in1 = in(1); 166 Node *in2 = in(2); 167 uint op1 = in1->Opcode(); 168 uint op2 = in2->Opcode(); 169 170 #ifdef ASSERT 171 // Check for dead loop 172 if ((in1 == this) || (in2 == this) || 173 ((op1 == Op_AddI || op1 == Op_SubI) && 174 ((in1->in(1) == this) || (in1->in(2) == this) || 175 (in1->in(1) == in1) || (in1->in(2) == in1)))) { 176 assert(false, "dead loop in SubINode::Ideal"); 177 } 178 #endif 179 180 const Type *t2 = phase->type( in2 ); 181 if( t2 == Type::TOP ) return NULL; 182 // Convert "x-c0" into "x+ -c0". 183 if( t2->base() == Type::Int ){ // Might be bottom or top... 184 const TypeInt *i = t2->is_int(); 185 if( i->is_con() ) 186 return new AddINode(in1, phase->intcon(-i->get_con())); 187 } 188 189 // Convert "(x+c0) - y" into (x-y) + c0" 190 // Do not collapse (x+c0)-y if "+" is a loop increment or 191 // if "y" is a loop induction variable. 192 if( op1 == Op_AddI && ok_to_convert(in1, in2) ) { 193 const Type *tadd = phase->type( in1->in(2) ); 194 if( tadd->singleton() && tadd != Type::TOP ) { 195 Node *sub2 = phase->transform( new SubINode( in1->in(1), in2 )); 196 return new AddINode( sub2, in1->in(2) ); 197 } 198 } 199 200 // Convert "x - (y+c0)" into "(x-y) - c0" AND 201 // Convert "c1 - (y+c0)" into "(c1-c0) - y" 202 // Need the same check as in above optimization but reversed. 203 if (op2 == Op_AddI 204 && ok_to_convert(in2, in1) 205 && in2->in(2)->Opcode() == Op_ConI) { 206 jint c0 = phase->type(in2->in(2))->isa_int()->get_con(); 207 Node* in21 = in2->in(1); 208 if (in1->Opcode() == Op_ConI) { 209 // Match c1 210 jint c1 = phase->type(in1)->isa_int()->get_con(); 211 Node* sub2 = phase->intcon(java_subtract(c1, c0)); 212 return new SubINode(sub2, in21); 213 } else { 214 // Match x 215 Node* sub2 = phase->transform(new SubINode(in1, in21)); 216 Node* neg_c0 = phase->intcon(-c0); 217 return new AddINode(sub2, neg_c0); 218 } 219 } 220 221 const Type *t1 = phase->type( in1 ); 222 if( t1 == Type::TOP ) return NULL; 223 224 #ifdef ASSERT 225 // Check for dead loop 226 if ((op2 == Op_AddI || op2 == Op_SubI) && 227 ((in2->in(1) == this) || (in2->in(2) == this) || 228 (in2->in(1) == in2) || (in2->in(2) == in2))) { 229 assert(false, "dead loop in SubINode::Ideal"); 230 } 231 #endif 232 233 // Convert "x - (x+y)" into "-y" 234 if (op2 == Op_AddI && in1 == in2->in(1)) { 235 return new SubINode(phase->intcon(0), in2->in(2)); 236 } 237 // Convert "(x-y) - x" into "-y" 238 if (op1 == Op_SubI && in1->in(1) == in2) { 239 return new SubINode(phase->intcon(0), in1->in(2)); 240 } 241 // Convert "x - (y+x)" into "-y" 242 if (op2 == Op_AddI && in1 == in2->in(2)) { 243 return new SubINode(phase->intcon(0), in2->in(1)); 244 } 245 246 // Convert "0 - (x-y)" into "y-x", leave the double negation "-(-y)" to SubNode::Identity(). 247 if (t1 == TypeInt::ZERO && op2 == Op_SubI && phase->type(in2->in(1)) != TypeInt::ZERO) { 248 return new SubINode(in2->in(2), in2->in(1)); 249 } 250 251 // Convert "0 - (x+con)" into "-con-x" 252 jint con; 253 if( t1 == TypeInt::ZERO && op2 == Op_AddI && 254 (con = in2->in(2)->find_int_con(0)) != 0 ) 255 return new SubINode( phase->intcon(-con), in2->in(1) ); 256 257 // Convert "(X+A) - (X+B)" into "A - B" 258 if( op1 == Op_AddI && op2 == Op_AddI && in1->in(1) == in2->in(1) ) 259 return new SubINode( in1->in(2), in2->in(2) ); 260 261 // Convert "(A+X) - (B+X)" into "A - B" 262 if( op1 == Op_AddI && op2 == Op_AddI && in1->in(2) == in2->in(2) ) 263 return new SubINode( in1->in(1), in2->in(1) ); 264 265 // Convert "(A+X) - (X+B)" into "A - B" 266 if( op1 == Op_AddI && op2 == Op_AddI && in1->in(2) == in2->in(1) ) 267 return new SubINode( in1->in(1), in2->in(2) ); 268 269 // Convert "(X+A) - (B+X)" into "A - B" 270 if( op1 == Op_AddI && op2 == Op_AddI && in1->in(1) == in2->in(2) ) 271 return new SubINode( in1->in(2), in2->in(1) ); 272 273 // Convert "A-(B-C)" into (A+C)-B", since add is commutative and generally 274 // nicer to optimize than subtract. 275 if( op2 == Op_SubI && in2->outcnt() == 1) { 276 Node *add1 = phase->transform( new AddINode( in1, in2->in(2) ) ); 277 return new SubINode( add1, in2->in(1) ); 278 } 279 280 // Associative 281 if (op1 == Op_MulI && op2 == Op_MulI) { 282 Node* sub_in1 = NULL; 283 Node* sub_in2 = NULL; 284 Node* mul_in = NULL; 285 286 if (in1->in(1) == in2->in(1)) { 287 // Convert "a*b-a*c into a*(b-c) 288 sub_in1 = in1->in(2); 289 sub_in2 = in2->in(2); 290 mul_in = in1->in(1); 291 } else if (in1->in(2) == in2->in(1)) { 292 // Convert a*b-b*c into b*(a-c) 293 sub_in1 = in1->in(1); 294 sub_in2 = in2->in(2); 295 mul_in = in1->in(2); 296 } else if (in1->in(2) == in2->in(2)) { 297 // Convert a*c-b*c into (a-b)*c 298 sub_in1 = in1->in(1); 299 sub_in2 = in2->in(1); 300 mul_in = in1->in(2); 301 } else if (in1->in(1) == in2->in(2)) { 302 // Convert a*b-c*a into a*(b-c) 303 sub_in1 = in1->in(2); 304 sub_in2 = in2->in(1); 305 mul_in = in1->in(1); 306 } 307 308 if (mul_in != NULL) { 309 Node* sub = phase->transform(new SubINode(sub_in1, sub_in2)); 310 return new MulINode(mul_in, sub); 311 } 312 } 313 314 // Convert "0-(A>>31)" into "(A>>>31)" 315 if ( op2 == Op_RShiftI ) { 316 Node *in21 = in2->in(1); 317 Node *in22 = in2->in(2); 318 const TypeInt *zero = phase->type(in1)->isa_int(); 319 const TypeInt *t21 = phase->type(in21)->isa_int(); 320 const TypeInt *t22 = phase->type(in22)->isa_int(); 321 if ( t21 && t22 && zero == TypeInt::ZERO && t22->is_con(31) ) { 322 return new URShiftINode(in21, in22); 323 } 324 } 325 326 return NULL; 327 } 328 329 //------------------------------sub-------------------------------------------- 330 // A subtract node differences it's two inputs. 331 const Type *SubINode::sub( const Type *t1, const Type *t2 ) const { 332 const TypeInt *r0 = t1->is_int(); // Handy access 333 const TypeInt *r1 = t2->is_int(); 334 int32_t lo = java_subtract(r0->_lo, r1->_hi); 335 int32_t hi = java_subtract(r0->_hi, r1->_lo); 336 337 // We next check for 32-bit overflow. 338 // If that happens, we just assume all integers are possible. 339 if( (((r0->_lo ^ r1->_hi) >= 0) || // lo ends have same signs OR 340 ((r0->_lo ^ lo) >= 0)) && // lo results have same signs AND 341 (((r0->_hi ^ r1->_lo) >= 0) || // hi ends have same signs OR 342 ((r0->_hi ^ hi) >= 0)) ) // hi results have same signs 343 return TypeInt::make(lo,hi,MAX2(r0->_widen,r1->_widen)); 344 else // Overflow; assume all integers 345 return TypeInt::INT; 346 } 347 348 //============================================================================= 349 //------------------------------Ideal------------------------------------------ 350 Node *SubLNode::Ideal(PhaseGVN *phase, bool can_reshape) { 351 Node *in1 = in(1); 352 Node *in2 = in(2); 353 uint op1 = in1->Opcode(); 354 uint op2 = in2->Opcode(); 355 356 #ifdef ASSERT 357 // Check for dead loop 358 if ((in1 == this) || (in2 == this) || 359 ((op1 == Op_AddL || op1 == Op_SubL) && 360 ((in1->in(1) == this) || (in1->in(2) == this) || 361 (in1->in(1) == in1) || (in1->in(2) == in1)))) { 362 assert(false, "dead loop in SubLNode::Ideal"); 363 } 364 #endif 365 366 if( phase->type( in2 ) == Type::TOP ) return NULL; 367 const TypeLong *i = phase->type( in2 )->isa_long(); 368 // Convert "x-c0" into "x+ -c0". 369 if( i && // Might be bottom or top... 370 i->is_con() ) 371 return new AddLNode(in1, phase->longcon(-i->get_con())); 372 373 // Convert "(x+c0) - y" into (x-y) + c0" 374 // Do not collapse (x+c0)-y if "+" is a loop increment or 375 // if "y" is a loop induction variable. 376 if( op1 == Op_AddL && ok_to_convert(in1, in2) ) { 377 Node *in11 = in1->in(1); 378 const Type *tadd = phase->type( in1->in(2) ); 379 if( tadd->singleton() && tadd != Type::TOP ) { 380 Node *sub2 = phase->transform( new SubLNode( in11, in2 )); 381 return new AddLNode( sub2, in1->in(2) ); 382 } 383 } 384 385 // Convert "x - (y+c0)" into "(x-y) - c0" AND 386 // Convert "c1 - (y+c0)" into "(c1-c0) - y" 387 // Need the same check as in above optimization but reversed. 388 if (op2 == Op_AddL 389 && ok_to_convert(in2, in1) 390 && in2->in(2)->Opcode() == Op_ConL) { 391 jlong c0 = phase->type(in2->in(2))->isa_long()->get_con(); 392 Node* in21 = in2->in(1); 393 if (in1->Opcode() == Op_ConL) { 394 // Match c1 395 jlong c1 = phase->type(in1)->isa_long()->get_con(); 396 Node* sub2 = phase->longcon(java_subtract(c1, c0)); 397 return new SubLNode(sub2, in21); 398 } else { 399 Node* sub2 = phase->transform(new SubLNode(in1, in21)); 400 Node* neg_c0 = phase->longcon(-c0); 401 return new AddLNode(sub2, neg_c0); 402 } 403 } 404 405 const Type *t1 = phase->type( in1 ); 406 if( t1 == Type::TOP ) return NULL; 407 408 #ifdef ASSERT 409 // Check for dead loop 410 if ((op2 == Op_AddL || op2 == Op_SubL) && 411 ((in2->in(1) == this) || (in2->in(2) == this) || 412 (in2->in(1) == in2) || (in2->in(2) == in2))) { 413 assert(false, "dead loop in SubLNode::Ideal"); 414 } 415 #endif 416 417 // Convert "x - (x+y)" into "-y" 418 if (op2 == Op_AddL && in1 == in2->in(1)) { 419 return new SubLNode(phase->makecon(TypeLong::ZERO), in2->in(2)); 420 } 421 // Convert "(x-y) - x" into "-y" 422 if (op1 == Op_SubL && in1->in(1) == in2) { 423 return new SubLNode(phase->makecon(TypeLong::ZERO), in1->in(2)); 424 } 425 // Convert "x - (y+x)" into "-y" 426 if (op2 == Op_AddL && in1 == in2->in(2)) { 427 return new SubLNode(phase->makecon(TypeLong::ZERO), in2->in(1)); 428 } 429 430 // Convert "0 - (x-y)" into "y-x", leave the double negation "-(-y)" to SubNode::Identity. 431 if (t1 == TypeLong::ZERO && op2 == Op_SubL && phase->type(in2->in(1)) != TypeLong::ZERO) { 432 return new SubLNode(in2->in(2), in2->in(1)); 433 } 434 435 // Convert "(X+A) - (X+B)" into "A - B" 436 if( op1 == Op_AddL && op2 == Op_AddL && in1->in(1) == in2->in(1) ) 437 return new SubLNode( in1->in(2), in2->in(2) ); 438 439 // Convert "(A+X) - (B+X)" into "A - B" 440 if( op1 == Op_AddL && op2 == Op_AddL && in1->in(2) == in2->in(2) ) 441 return new SubLNode( in1->in(1), in2->in(1) ); 442 443 // Convert "(A+X) - (X+B)" into "A - B" 444 if( op1 == Op_AddL && op2 == Op_AddL && in1->in(2) == in2->in(1) ) 445 return new SubLNode( in1->in(1), in2->in(2) ); 446 447 // Convert "(X+A) - (B+X)" into "A - B" 448 if( op1 == Op_AddL && op2 == Op_AddL && in1->in(1) == in2->in(2) ) 449 return new SubLNode( in1->in(2), in2->in(1) ); 450 451 // Convert "A-(B-C)" into (A+C)-B" 452 if( op2 == Op_SubL && in2->outcnt() == 1) { 453 Node *add1 = phase->transform( new AddLNode( in1, in2->in(2) ) ); 454 return new SubLNode( add1, in2->in(1) ); 455 } 456 457 // Associative 458 if (op1 == Op_MulL && op2 == Op_MulL) { 459 Node* sub_in1 = NULL; 460 Node* sub_in2 = NULL; 461 Node* mul_in = NULL; 462 463 if (in1->in(1) == in2->in(1)) { 464 // Convert "a*b-a*c into a*(b+c) 465 sub_in1 = in1->in(2); 466 sub_in2 = in2->in(2); 467 mul_in = in1->in(1); 468 } else if (in1->in(2) == in2->in(1)) { 469 // Convert a*b-b*c into b*(a-c) 470 sub_in1 = in1->in(1); 471 sub_in2 = in2->in(2); 472 mul_in = in1->in(2); 473 } else if (in1->in(2) == in2->in(2)) { 474 // Convert a*c-b*c into (a-b)*c 475 sub_in1 = in1->in(1); 476 sub_in2 = in2->in(1); 477 mul_in = in1->in(2); 478 } else if (in1->in(1) == in2->in(2)) { 479 // Convert a*b-c*a into a*(b-c) 480 sub_in1 = in1->in(2); 481 sub_in2 = in2->in(1); 482 mul_in = in1->in(1); 483 } 484 485 if (mul_in != NULL) { 486 Node* sub = phase->transform(new SubLNode(sub_in1, sub_in2)); 487 return new MulLNode(mul_in, sub); 488 } 489 } 490 491 // Convert "0L-(A>>63)" into "(A>>>63)" 492 if ( op2 == Op_RShiftL ) { 493 Node *in21 = in2->in(1); 494 Node *in22 = in2->in(2); 495 const TypeLong *zero = phase->type(in1)->isa_long(); 496 const TypeLong *t21 = phase->type(in21)->isa_long(); 497 const TypeInt *t22 = phase->type(in22)->isa_int(); 498 if ( t21 && t22 && zero == TypeLong::ZERO && t22->is_con(63) ) { 499 return new URShiftLNode(in21, in22); 500 } 501 } 502 503 return NULL; 504 } 505 506 //------------------------------sub-------------------------------------------- 507 // A subtract node differences it's two inputs. 508 const Type *SubLNode::sub( const Type *t1, const Type *t2 ) const { 509 const TypeLong *r0 = t1->is_long(); // Handy access 510 const TypeLong *r1 = t2->is_long(); 511 jlong lo = java_subtract(r0->_lo, r1->_hi); 512 jlong hi = java_subtract(r0->_hi, r1->_lo); 513 514 // We next check for 32-bit overflow. 515 // If that happens, we just assume all integers are possible. 516 if( (((r0->_lo ^ r1->_hi) >= 0) || // lo ends have same signs OR 517 ((r0->_lo ^ lo) >= 0)) && // lo results have same signs AND 518 (((r0->_hi ^ r1->_lo) >= 0) || // hi ends have same signs OR 519 ((r0->_hi ^ hi) >= 0)) ) // hi results have same signs 520 return TypeLong::make(lo,hi,MAX2(r0->_widen,r1->_widen)); 521 else // Overflow; assume all integers 522 return TypeLong::LONG; 523 } 524 525 //============================================================================= 526 //------------------------------Value------------------------------------------ 527 // A subtract node differences its two inputs. 528 const Type* SubFPNode::Value(PhaseGVN* phase) const { 529 const Node* in1 = in(1); 530 const Node* in2 = in(2); 531 // Either input is TOP ==> the result is TOP 532 const Type* t1 = (in1 == this) ? Type::TOP : phase->type(in1); 533 if( t1 == Type::TOP ) return Type::TOP; 534 const Type* t2 = (in2 == this) ? Type::TOP : phase->type(in2); 535 if( t2 == Type::TOP ) return Type::TOP; 536 537 // if both operands are infinity of same sign, the result is NaN; do 538 // not replace with zero 539 if (t1->is_finite() && t2->is_finite() && in1 == in2) { 540 return add_id(); 541 } 542 543 // Either input is BOTTOM ==> the result is the local BOTTOM 544 const Type *bot = bottom_type(); 545 if( (t1 == bot) || (t2 == bot) || 546 (t1 == Type::BOTTOM) || (t2 == Type::BOTTOM) ) 547 return bot; 548 549 return sub(t1,t2); // Local flavor of type subtraction 550 } 551 552 553 //============================================================================= 554 //------------------------------Ideal------------------------------------------ 555 Node *SubFNode::Ideal(PhaseGVN *phase, bool can_reshape) { 556 const Type *t2 = phase->type( in(2) ); 557 // Convert "x-c0" into "x+ -c0". 558 if( t2->base() == Type::FloatCon ) { // Might be bottom or top... 559 // return new (phase->C, 3) AddFNode(in(1), phase->makecon( TypeF::make(-t2->getf()) ) ); 560 } 561 562 // Cannot replace 0.0-X with -X because a 'fsub' bytecode computes 563 // 0.0-0.0 as +0.0, while a 'fneg' bytecode computes -0.0. 564 //if( phase->type(in(1)) == TypeF::ZERO ) 565 //return new (phase->C, 2) NegFNode(in(2)); 566 567 return NULL; 568 } 569 570 //------------------------------sub-------------------------------------------- 571 // A subtract node differences its two inputs. 572 const Type *SubFNode::sub( const Type *t1, const Type *t2 ) const { 573 // no folding if one of operands is infinity or NaN, do not do constant folding 574 if( g_isfinite(t1->getf()) && g_isfinite(t2->getf()) ) { 575 return TypeF::make( t1->getf() - t2->getf() ); 576 } 577 else if( g_isnan(t1->getf()) ) { 578 return t1; 579 } 580 else if( g_isnan(t2->getf()) ) { 581 return t2; 582 } 583 else { 584 return Type::FLOAT; 585 } 586 } 587 588 //============================================================================= 589 //------------------------------Ideal------------------------------------------ 590 Node *SubDNode::Ideal(PhaseGVN *phase, bool can_reshape){ 591 const Type *t2 = phase->type( in(2) ); 592 // Convert "x-c0" into "x+ -c0". 593 if( t2->base() == Type::DoubleCon ) { // Might be bottom or top... 594 // return new (phase->C, 3) AddDNode(in(1), phase->makecon( TypeD::make(-t2->getd()) ) ); 595 } 596 597 // Cannot replace 0.0-X with -X because a 'dsub' bytecode computes 598 // 0.0-0.0 as +0.0, while a 'dneg' bytecode computes -0.0. 599 //if( phase->type(in(1)) == TypeD::ZERO ) 600 //return new (phase->C, 2) NegDNode(in(2)); 601 602 return NULL; 603 } 604 605 //------------------------------sub-------------------------------------------- 606 // A subtract node differences its two inputs. 607 const Type *SubDNode::sub( const Type *t1, const Type *t2 ) const { 608 // no folding if one of operands is infinity or NaN, do not do constant folding 609 if( g_isfinite(t1->getd()) && g_isfinite(t2->getd()) ) { 610 return TypeD::make( t1->getd() - t2->getd() ); 611 } 612 else if( g_isnan(t1->getd()) ) { 613 return t1; 614 } 615 else if( g_isnan(t2->getd()) ) { 616 return t2; 617 } 618 else { 619 return Type::DOUBLE; 620 } 621 } 622 623 //============================================================================= 624 //------------------------------Idealize--------------------------------------- 625 // Unlike SubNodes, compare must still flatten return value to the 626 // range -1, 0, 1. 627 // And optimizations like those for (X + Y) - X fail if overflow happens. 628 Node* CmpNode::Identity(PhaseGVN* phase) { 629 return this; 630 } 631 632 #ifndef PRODUCT 633 //----------------------------related------------------------------------------ 634 // Related nodes of comparison nodes include all data inputs (until hitting a 635 // control boundary) as well as all outputs until and including control nodes 636 // as well as their projections. In compact mode, data inputs till depth 1 and 637 // all outputs till depth 1 are considered. 638 void CmpNode::related(GrowableArray<Node*> *in_rel, GrowableArray<Node*> *out_rel, bool compact) const { 639 if (compact) { 640 this->collect_nodes(in_rel, 1, false, true); 641 this->collect_nodes(out_rel, -1, false, false); 642 } else { 643 this->collect_nodes_in_all_data(in_rel, false); 644 this->collect_nodes_out_all_ctrl_boundary(out_rel); 645 // Now, find all control nodes in out_rel, and include their projections 646 // and projection targets (if any) in the result. 647 GrowableArray<Node*> proj(Compile::current()->unique()); 648 for (GrowableArrayIterator<Node*> it = out_rel->begin(); it != out_rel->end(); ++it) { 649 Node* n = *it; 650 if (n->is_CFG() && !n->is_Proj()) { 651 // Assume projections and projection targets are found at levels 1 and 2. 652 n->collect_nodes(&proj, -2, false, false); 653 for (GrowableArrayIterator<Node*> p = proj.begin(); p != proj.end(); ++p) { 654 out_rel->append_if_missing(*p); 655 } 656 proj.clear(); 657 } 658 } 659 } 660 } 661 662 #endif 663 664 CmpNode *CmpNode::make(Node *in1, Node *in2, BasicType bt, bool unsigned_comp) { 665 switch (bt) { 666 case T_INT: 667 if (unsigned_comp) { 668 return new CmpUNode(in1, in2); 669 } 670 return new CmpINode(in1, in2); 671 case T_LONG: 672 if (unsigned_comp) { 673 return new CmpULNode(in1, in2); 674 } 675 return new CmpLNode(in1, in2); 676 default: 677 fatal("Not implemented for %s", type2name(bt)); 678 } 679 return NULL; 680 } 681 682 //============================================================================= 683 //------------------------------cmp-------------------------------------------- 684 // Simplify a CmpI (compare 2 integers) node, based on local information. 685 // If both inputs are constants, compare them. 686 const Type *CmpINode::sub( const Type *t1, const Type *t2 ) const { 687 const TypeInt *r0 = t1->is_int(); // Handy access 688 const TypeInt *r1 = t2->is_int(); 689 690 if( r0->_hi < r1->_lo ) // Range is always low? 691 return TypeInt::CC_LT; 692 else if( r0->_lo > r1->_hi ) // Range is always high? 693 return TypeInt::CC_GT; 694 695 else if( r0->is_con() && r1->is_con() ) { // comparing constants? 696 assert(r0->get_con() == r1->get_con(), "must be equal"); 697 return TypeInt::CC_EQ; // Equal results. 698 } else if( r0->_hi == r1->_lo ) // Range is never high? 699 return TypeInt::CC_LE; 700 else if( r0->_lo == r1->_hi ) // Range is never low? 701 return TypeInt::CC_GE; 702 return TypeInt::CC; // else use worst case results 703 } 704 705 // Simplify a CmpU (compare 2 integers) node, based on local information. 706 // If both inputs are constants, compare them. 707 const Type *CmpUNode::sub( const Type *t1, const Type *t2 ) const { 708 assert(!t1->isa_ptr(), "obsolete usage of CmpU"); 709 710 // comparing two unsigned ints 711 const TypeInt *r0 = t1->is_int(); // Handy access 712 const TypeInt *r1 = t2->is_int(); 713 714 // Current installed version 715 // Compare ranges for non-overlap 716 juint lo0 = r0->_lo; 717 juint hi0 = r0->_hi; 718 juint lo1 = r1->_lo; 719 juint hi1 = r1->_hi; 720 721 // If either one has both negative and positive values, 722 // it therefore contains both 0 and -1, and since [0..-1] is the 723 // full unsigned range, the type must act as an unsigned bottom. 724 bool bot0 = ((jint)(lo0 ^ hi0) < 0); 725 bool bot1 = ((jint)(lo1 ^ hi1) < 0); 726 727 if (bot0 || bot1) { 728 // All unsigned values are LE -1 and GE 0. 729 if (lo0 == 0 && hi0 == 0) { 730 return TypeInt::CC_LE; // 0 <= bot 731 } else if ((jint)lo0 == -1 && (jint)hi0 == -1) { 732 return TypeInt::CC_GE; // -1 >= bot 733 } else if (lo1 == 0 && hi1 == 0) { 734 return TypeInt::CC_GE; // bot >= 0 735 } else if ((jint)lo1 == -1 && (jint)hi1 == -1) { 736 return TypeInt::CC_LE; // bot <= -1 737 } 738 } else { 739 // We can use ranges of the form [lo..hi] if signs are the same. 740 assert(lo0 <= hi0 && lo1 <= hi1, "unsigned ranges are valid"); 741 // results are reversed, '-' > '+' for unsigned compare 742 if (hi0 < lo1) { 743 return TypeInt::CC_LT; // smaller 744 } else if (lo0 > hi1) { 745 return TypeInt::CC_GT; // greater 746 } else if (hi0 == lo1 && lo0 == hi1) { 747 return TypeInt::CC_EQ; // Equal results 748 } else if (lo0 >= hi1) { 749 return TypeInt::CC_GE; 750 } else if (hi0 <= lo1) { 751 // Check for special case in Hashtable::get. (See below.) 752 if ((jint)lo0 >= 0 && (jint)lo1 >= 0 && is_index_range_check()) 753 return TypeInt::CC_LT; 754 return TypeInt::CC_LE; 755 } 756 } 757 // Check for special case in Hashtable::get - the hash index is 758 // mod'ed to the table size so the following range check is useless. 759 // Check for: (X Mod Y) CmpU Y, where the mod result and Y both have 760 // to be positive. 761 // (This is a gross hack, since the sub method never 762 // looks at the structure of the node in any other case.) 763 if ((jint)lo0 >= 0 && (jint)lo1 >= 0 && is_index_range_check()) 764 return TypeInt::CC_LT; 765 return TypeInt::CC; // else use worst case results 766 } 767 768 const Type* CmpUNode::Value(PhaseGVN* phase) const { 769 const Type* t = SubNode::Value_common(phase); 770 if (t != NULL) { 771 return t; 772 } 773 const Node* in1 = in(1); 774 const Node* in2 = in(2); 775 const Type* t1 = phase->type(in1); 776 const Type* t2 = phase->type(in2); 777 assert(t1->isa_int(), "CmpU has only Int type inputs"); 778 if (t2 == TypeInt::INT) { // Compare to bottom? 779 return bottom_type(); 780 } 781 uint in1_op = in1->Opcode(); 782 if (in1_op == Op_AddI || in1_op == Op_SubI) { 783 // The problem rise when result of AddI(SubI) may overflow 784 // signed integer value. Let say the input type is 785 // [256, maxint] then +128 will create 2 ranges due to 786 // overflow: [minint, minint+127] and [384, maxint]. 787 // But C2 type system keep only 1 type range and as result 788 // it use general [minint, maxint] for this case which we 789 // can't optimize. 790 // 791 // Make 2 separate type ranges based on types of AddI(SubI) inputs 792 // and compare results of their compare. If results are the same 793 // CmpU node can be optimized. 794 const Node* in11 = in1->in(1); 795 const Node* in12 = in1->in(2); 796 const Type* t11 = (in11 == in1) ? Type::TOP : phase->type(in11); 797 const Type* t12 = (in12 == in1) ? Type::TOP : phase->type(in12); 798 // Skip cases when input types are top or bottom. 799 if ((t11 != Type::TOP) && (t11 != TypeInt::INT) && 800 (t12 != Type::TOP) && (t12 != TypeInt::INT)) { 801 const TypeInt *r0 = t11->is_int(); 802 const TypeInt *r1 = t12->is_int(); 803 jlong lo_r0 = r0->_lo; 804 jlong hi_r0 = r0->_hi; 805 jlong lo_r1 = r1->_lo; 806 jlong hi_r1 = r1->_hi; 807 if (in1_op == Op_SubI) { 808 jlong tmp = hi_r1; 809 hi_r1 = -lo_r1; 810 lo_r1 = -tmp; 811 // Note, for substructing [minint,x] type range 812 // long arithmetic provides correct overflow answer. 813 // The confusion come from the fact that in 32-bit 814 // -minint == minint but in 64-bit -minint == maxint+1. 815 } 816 jlong lo_long = lo_r0 + lo_r1; 817 jlong hi_long = hi_r0 + hi_r1; 818 int lo_tr1 = min_jint; 819 int hi_tr1 = (int)hi_long; 820 int lo_tr2 = (int)lo_long; 821 int hi_tr2 = max_jint; 822 bool underflow = lo_long != (jlong)lo_tr2; 823 bool overflow = hi_long != (jlong)hi_tr1; 824 // Use sub(t1, t2) when there is no overflow (one type range) 825 // or when both overflow and underflow (too complex). 826 if ((underflow != overflow) && (hi_tr1 < lo_tr2)) { 827 // Overflow only on one boundary, compare 2 separate type ranges. 828 int w = MAX2(r0->_widen, r1->_widen); // _widen does not matter here 829 const TypeInt* tr1 = TypeInt::make(lo_tr1, hi_tr1, w); 830 const TypeInt* tr2 = TypeInt::make(lo_tr2, hi_tr2, w); 831 const Type* cmp1 = sub(tr1, t2); 832 const Type* cmp2 = sub(tr2, t2); 833 if (cmp1 == cmp2) { 834 return cmp1; // Hit! 835 } 836 } 837 } 838 } 839 840 return sub(t1, t2); // Local flavor of type subtraction 841 } 842 843 bool CmpUNode::is_index_range_check() const { 844 // Check for the "(X ModI Y) CmpU Y" shape 845 return (in(1)->Opcode() == Op_ModI && 846 in(1)->in(2)->eqv_uncast(in(2))); 847 } 848 849 //------------------------------Idealize--------------------------------------- 850 Node *CmpINode::Ideal( PhaseGVN *phase, bool can_reshape ) { 851 if (phase->type(in(2))->higher_equal(TypeInt::ZERO)) { 852 switch (in(1)->Opcode()) { 853 case Op_CmpL3: // Collapse a CmpL3/CmpI into a CmpL 854 return new CmpLNode(in(1)->in(1),in(1)->in(2)); 855 case Op_CmpF3: // Collapse a CmpF3/CmpI into a CmpF 856 return new CmpFNode(in(1)->in(1),in(1)->in(2)); 857 case Op_CmpD3: // Collapse a CmpD3/CmpI into a CmpD 858 return new CmpDNode(in(1)->in(1),in(1)->in(2)); 859 //case Op_SubI: 860 // If (x - y) cannot overflow, then ((x - y) <?> 0) 861 // can be turned into (x <?> y). 862 // This is handled (with more general cases) by Ideal_sub_algebra. 863 } 864 } 865 return NULL; // No change 866 } 867 868 //------------------------------Ideal------------------------------------------ 869 Node* CmpLNode::Ideal(PhaseGVN* phase, bool can_reshape) { 870 Node* a = NULL; 871 Node* b = NULL; 872 if (is_double_null_check(phase, a, b) && (phase->type(a)->is_zero_type() || phase->type(b)->is_zero_type())) { 873 // Degraded to a simple null check, use old acmp 874 return new CmpPNode(a, b); 875 } 876 const TypeLong *t2 = phase->type(in(2))->isa_long(); 877 if (Opcode() == Op_CmpL && in(1)->Opcode() == Op_ConvI2L && t2 && t2->is_con()) { 878 const jlong con = t2->get_con(); 879 if (con >= min_jint && con <= max_jint) { 880 return new CmpINode(in(1)->in(1), phase->intcon((jint)con)); 881 } 882 } 883 return NULL; 884 } 885 886 // Match double null check emitted by Compile::optimize_acmp() 887 bool CmpLNode::is_double_null_check(PhaseGVN* phase, Node*& a, Node*& b) const { 888 if (in(1)->Opcode() == Op_OrL && 889 in(1)->in(1)->Opcode() == Op_CastP2X && 890 in(1)->in(2)->Opcode() == Op_CastP2X && 891 in(2)->bottom_type()->is_zero_type()) { 892 assert(EnableValhalla, "unexpected double null check"); 893 a = in(1)->in(1)->in(1); 894 b = in(1)->in(2)->in(1); 895 return true; 896 } 897 return false; 898 } 899 900 //------------------------------Value------------------------------------------ 901 const Type* CmpLNode::Value(PhaseGVN* phase) const { 902 Node* a = NULL; 903 Node* b = NULL; 904 if (is_double_null_check(phase, a, b) && (!phase->type(a)->maybe_null() || !phase->type(b)->maybe_null())) { 905 // One operand is never NULL, emit constant false 906 return TypeInt::CC_GT; 907 } 908 return SubNode::Value(phase); 909 } 910 911 //============================================================================= 912 // Simplify a CmpL (compare 2 longs ) node, based on local information. 913 // If both inputs are constants, compare them. 914 const Type *CmpLNode::sub( const Type *t1, const Type *t2 ) const { 915 const TypeLong *r0 = t1->is_long(); // Handy access 916 const TypeLong *r1 = t2->is_long(); 917 918 if( r0->_hi < r1->_lo ) // Range is always low? 919 return TypeInt::CC_LT; 920 else if( r0->_lo > r1->_hi ) // Range is always high? 921 return TypeInt::CC_GT; 922 923 else if( r0->is_con() && r1->is_con() ) { // comparing constants? 924 assert(r0->get_con() == r1->get_con(), "must be equal"); 925 return TypeInt::CC_EQ; // Equal results. 926 } else if( r0->_hi == r1->_lo ) // Range is never high? 927 return TypeInt::CC_LE; 928 else if( r0->_lo == r1->_hi ) // Range is never low? 929 return TypeInt::CC_GE; 930 return TypeInt::CC; // else use worst case results 931 } 932 933 934 // Simplify a CmpUL (compare 2 unsigned longs) node, based on local information. 935 // If both inputs are constants, compare them. 936 const Type* CmpULNode::sub(const Type* t1, const Type* t2) const { 937 assert(!t1->isa_ptr(), "obsolete usage of CmpUL"); 938 939 // comparing two unsigned longs 940 const TypeLong* r0 = t1->is_long(); // Handy access 941 const TypeLong* r1 = t2->is_long(); 942 943 // Current installed version 944 // Compare ranges for non-overlap 945 julong lo0 = r0->_lo; 946 julong hi0 = r0->_hi; 947 julong lo1 = r1->_lo; 948 julong hi1 = r1->_hi; 949 950 // If either one has both negative and positive values, 951 // it therefore contains both 0 and -1, and since [0..-1] is the 952 // full unsigned range, the type must act as an unsigned bottom. 953 bool bot0 = ((jlong)(lo0 ^ hi0) < 0); 954 bool bot1 = ((jlong)(lo1 ^ hi1) < 0); 955 956 if (bot0 || bot1) { 957 // All unsigned values are LE -1 and GE 0. 958 if (lo0 == 0 && hi0 == 0) { 959 return TypeInt::CC_LE; // 0 <= bot 960 } else if ((jlong)lo0 == -1 && (jlong)hi0 == -1) { 961 return TypeInt::CC_GE; // -1 >= bot 962 } else if (lo1 == 0 && hi1 == 0) { 963 return TypeInt::CC_GE; // bot >= 0 964 } else if ((jlong)lo1 == -1 && (jlong)hi1 == -1) { 965 return TypeInt::CC_LE; // bot <= -1 966 } 967 } else { 968 // We can use ranges of the form [lo..hi] if signs are the same. 969 assert(lo0 <= hi0 && lo1 <= hi1, "unsigned ranges are valid"); 970 // results are reversed, '-' > '+' for unsigned compare 971 if (hi0 < lo1) { 972 return TypeInt::CC_LT; // smaller 973 } else if (lo0 > hi1) { 974 return TypeInt::CC_GT; // greater 975 } else if (hi0 == lo1 && lo0 == hi1) { 976 return TypeInt::CC_EQ; // Equal results 977 } else if (lo0 >= hi1) { 978 return TypeInt::CC_GE; 979 } else if (hi0 <= lo1) { 980 return TypeInt::CC_LE; 981 } 982 } 983 984 return TypeInt::CC; // else use worst case results 985 } 986 987 //============================================================================= 988 //------------------------------sub-------------------------------------------- 989 // Simplify an CmpP (compare 2 pointers) node, based on local information. 990 // If both inputs are constants, compare them. 991 const Type *CmpPNode::sub( const Type *t1, const Type *t2 ) const { 992 const TypePtr *r0 = t1->is_ptr(); // Handy access 993 const TypePtr *r1 = t2->is_ptr(); 994 995 // Undefined inputs makes for an undefined result 996 if( TypePtr::above_centerline(r0->_ptr) || 997 TypePtr::above_centerline(r1->_ptr) ) 998 return Type::TOP; 999 1000 if (r0 == r1 && r0->singleton()) { 1001 // Equal pointer constants (klasses, nulls, etc.) 1002 return TypeInt::CC_EQ; 1003 } 1004 1005 // See if it is 2 unrelated classes. 1006 const TypeOopPtr* oop_p0 = r0->isa_oopptr(); 1007 const TypeOopPtr* oop_p1 = r1->isa_oopptr(); 1008 bool both_oop_ptr = oop_p0 && oop_p1; 1009 1010 if (both_oop_ptr) { 1011 Node* in1 = in(1)->uncast(); 1012 Node* in2 = in(2)->uncast(); 1013 AllocateNode* alloc1 = AllocateNode::Ideal_allocation(in1, NULL); 1014 AllocateNode* alloc2 = AllocateNode::Ideal_allocation(in2, NULL); 1015 if (MemNode::detect_ptr_independence(in1, alloc1, in2, alloc2, NULL)) { 1016 return TypeInt::CC_GT; // different pointers 1017 } 1018 } 1019 1020 const TypeKlassPtr* klass_p0 = r0->isa_klassptr(); 1021 const TypeKlassPtr* klass_p1 = r1->isa_klassptr(); 1022 1023 if (both_oop_ptr || (klass_p0 && klass_p1)) { // both or neither are klass pointers 1024 ciKlass* klass0 = NULL; 1025 bool xklass0 = false; 1026 ciKlass* klass1 = NULL; 1027 bool xklass1 = false; 1028 1029 if (oop_p0) { 1030 klass0 = oop_p0->klass(); 1031 xklass0 = oop_p0->klass_is_exact(); 1032 } else { 1033 assert(klass_p0, "must be non-null if oop_p0 is null"); 1034 klass0 = klass_p0->klass(); 1035 xklass0 = klass_p0->klass_is_exact(); 1036 } 1037 1038 if (oop_p1) { 1039 klass1 = oop_p1->klass(); 1040 xklass1 = oop_p1->klass_is_exact(); 1041 } else { 1042 assert(klass_p1, "must be non-null if oop_p1 is null"); 1043 klass1 = klass_p1->klass(); 1044 xklass1 = klass_p1->klass_is_exact(); 1045 } 1046 1047 if (klass0 && klass1 && 1048 klass0->is_loaded() && !klass0->is_interface() && // do not trust interfaces 1049 klass1->is_loaded() && !klass1->is_interface() && 1050 (!klass0->is_obj_array_klass() || 1051 !klass0->as_obj_array_klass()->base_element_klass()->is_interface()) && 1052 (!klass1->is_obj_array_klass() || 1053 !klass1->as_obj_array_klass()->base_element_klass()->is_interface())) { 1054 bool unrelated_classes = false; 1055 // See if neither subclasses the other, or if the class on top 1056 // is precise. In either of these cases, the compare is known 1057 // to fail if at least one of the pointers is provably not null. 1058 if (klass0->equals(klass1)) { // if types are unequal but klasses are equal 1059 // Do nothing; we know nothing for imprecise types 1060 } else if (klass0->is_subtype_of(klass1)) { 1061 // If klass1's type is PRECISE, then classes are unrelated. 1062 unrelated_classes = xklass1; 1063 } else if (klass1->is_subtype_of(klass0)) { 1064 // If klass0's type is PRECISE, then classes are unrelated. 1065 unrelated_classes = xklass0; 1066 } else { // Neither subtypes the other 1067 unrelated_classes = true; 1068 } 1069 if (!unrelated_classes) { 1070 // Handle inline type arrays 1071 if ((r0->flatten_array() && (!r1->can_be_inline_type() || (klass1->is_inlinetype() && !klass1->flatten_array()))) || 1072 (r1->flatten_array() && (!r0->can_be_inline_type() || (klass0->is_inlinetype() && !klass0->flatten_array())))) { 1073 // One type is flattened in arrays but the other type is not. Must be unrelated. 1074 unrelated_classes = true; 1075 } else if ((r0->is_not_flat() && klass1->is_flat_array_klass()) || 1076 (r1->is_not_flat() && klass0->is_flat_array_klass())) { 1077 // One type is a non-flattened array and the other type is a flattened array. Must be unrelated. 1078 unrelated_classes = true; 1079 } else if ((r0->is_not_null_free() && klass1->is_array_klass() && klass1->as_array_klass()->is_elem_null_free()) || 1080 (r1->is_not_null_free() && klass0->is_array_klass() && klass0->as_array_klass()->is_elem_null_free())) { 1081 // One type is a non-null-free array and the other type is a null-free array. Must be unrelated. 1082 unrelated_classes = true; 1083 } 1084 } 1085 if (unrelated_classes) { 1086 // The oops classes are known to be unrelated. If the joined PTRs of 1087 // two oops is not Null and not Bottom, then we are sure that one 1088 // of the two oops is non-null, and the comparison will always fail. 1089 TypePtr::PTR jp = r0->join_ptr(r1->_ptr); 1090 if (jp != TypePtr::Null && jp != TypePtr::BotPTR) { 1091 return TypeInt::CC_GT; 1092 } 1093 } 1094 } 1095 } 1096 1097 // Known constants can be compared exactly 1098 // Null can be distinguished from any NotNull pointers 1099 // Unknown inputs makes an unknown result 1100 if( r0->singleton() ) { 1101 intptr_t bits0 = r0->get_con(); 1102 if( r1->singleton() ) 1103 return bits0 == r1->get_con() ? TypeInt::CC_EQ : TypeInt::CC_GT; 1104 return ( r1->_ptr == TypePtr::NotNull && bits0==0 ) ? TypeInt::CC_GT : TypeInt::CC; 1105 } else if( r1->singleton() ) { 1106 intptr_t bits1 = r1->get_con(); 1107 return ( r0->_ptr == TypePtr::NotNull && bits1==0 ) ? TypeInt::CC_GT : TypeInt::CC; 1108 } else 1109 return TypeInt::CC; 1110 } 1111 1112 static inline Node* isa_java_mirror_load(PhaseGVN* phase, Node* n) { 1113 // Return the klass node for (indirect load from OopHandle) 1114 // LoadBarrier?(LoadP(LoadP(AddP(foo:Klass, #java_mirror)))) 1115 // or NULL if not matching. 1116 BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2(); 1117 n = bs->step_over_gc_barrier(n); 1118 1119 if (n->Opcode() != Op_LoadP) return NULL; 1120 1121 const TypeInstPtr* tp = phase->type(n)->isa_instptr(); 1122 if (!tp || tp->klass() != phase->C->env()->Class_klass()) return NULL; 1123 1124 Node* adr = n->in(MemNode::Address); 1125 // First load from OopHandle: ((OopHandle)mirror)->resolve(); may need barrier. 1126 if (adr->Opcode() != Op_LoadP || !phase->type(adr)->isa_rawptr()) return NULL; 1127 adr = adr->in(MemNode::Address); 1128 1129 intptr_t off = 0; 1130 Node* k = AddPNode::Ideal_base_and_offset(adr, phase, off); 1131 if (k == NULL) return NULL; 1132 const TypeKlassPtr* tkp = phase->type(k)->isa_klassptr(); 1133 if (!tkp || off != in_bytes(Klass::java_mirror_offset())) return NULL; 1134 1135 // We've found the klass node of a Java mirror load. 1136 return k; 1137 } 1138 1139 static inline Node* isa_const_java_mirror(PhaseGVN* phase, Node* n) { 1140 // for ConP(Foo.class) return ConP(Foo.klass) 1141 // otherwise return NULL 1142 if (!n->is_Con()) return NULL; 1143 1144 const TypeInstPtr* tp = phase->type(n)->isa_instptr(); 1145 if (!tp) return NULL; 1146 1147 ciType* mirror_type = tp->java_mirror_type(); 1148 // TypeInstPtr::java_mirror_type() returns non-NULL for compile- 1149 // time Class constants only. 1150 if (!mirror_type) return NULL; 1151 1152 // x.getClass() == int.class can never be true (for all primitive types) 1153 // Return a ConP(NULL) node for this case. 1154 if (mirror_type->is_classless()) { 1155 return phase->makecon(TypePtr::NULL_PTR); 1156 } 1157 1158 // return the ConP(Foo.klass) 1159 assert(mirror_type->is_klass(), "mirror_type should represent a Klass*"); 1160 return phase->makecon(TypeKlassPtr::make(mirror_type->as_klass())); 1161 } 1162 1163 //------------------------------Ideal------------------------------------------ 1164 // Normalize comparisons between Java mirror loads to compare the klass instead. 1165 // 1166 // Also check for the case of comparing an unknown klass loaded from the primary 1167 // super-type array vs a known klass with no subtypes. This amounts to 1168 // checking to see an unknown klass subtypes a known klass with no subtypes; 1169 // this only happens on an exact match. We can shorten this test by 1 load. 1170 Node* CmpPNode::Ideal(PhaseGVN *phase, bool can_reshape) { 1171 // TODO 8284443 in(1) could be cast? 1172 if (in(1)->is_InlineTypePtr() && phase->type(in(2))->is_zero_type()) { 1173 // Null checking a scalarized but nullable inline type. Check the IsInit 1174 // input instead of the oop input to avoid keeping buffer allocations alive. 1175 return new CmpINode(in(1)->as_InlineTypePtr()->get_is_init(), phase->intcon(0)); 1176 } 1177 1178 // Normalize comparisons between Java mirrors into comparisons of the low- 1179 // level klass, where a dependent load could be shortened. 1180 // 1181 // The new pattern has a nice effect of matching the same pattern used in the 1182 // fast path of instanceof/checkcast/Class.isInstance(), which allows 1183 // redundant exact type check be optimized away by GVN. 1184 // For example, in 1185 // if (x.getClass() == Foo.class) { 1186 // Foo foo = (Foo) x; 1187 // // ... use a ... 1188 // } 1189 // a CmpPNode could be shared between if_acmpne and checkcast 1190 { 1191 Node* k1 = isa_java_mirror_load(phase, in(1)); 1192 Node* k2 = isa_java_mirror_load(phase, in(2)); 1193 Node* conk2 = isa_const_java_mirror(phase, in(2)); 1194 1195 if (k1 && (k2 || conk2)) { 1196 Node* lhs = k1; 1197 Node* rhs = (k2 != NULL) ? k2 : conk2; 1198 set_req_X(1, lhs, phase); 1199 set_req_X(2, rhs, phase); 1200 return this; 1201 } 1202 } 1203 1204 // Constant pointer on right? 1205 const TypeKlassPtr* t2 = phase->type(in(2))->isa_klassptr(); 1206 if (t2 == NULL || !t2->klass_is_exact()) 1207 return NULL; 1208 // Get the constant klass we are comparing to. 1209 ciKlass* superklass = t2->klass(); 1210 1211 // Now check for LoadKlass on left. 1212 Node* ldk1 = in(1); 1213 if (ldk1->is_DecodeNKlass()) { 1214 ldk1 = ldk1->in(1); 1215 if (ldk1->Opcode() != Op_LoadNKlass ) 1216 return NULL; 1217 } else if (ldk1->Opcode() != Op_LoadKlass ) 1218 return NULL; 1219 // Take apart the address of the LoadKlass: 1220 Node* adr1 = ldk1->in(MemNode::Address); 1221 intptr_t con2 = 0; 1222 Node* ldk2 = AddPNode::Ideal_base_and_offset(adr1, phase, con2); 1223 if (ldk2 == NULL) 1224 return NULL; 1225 if (con2 == oopDesc::klass_offset_in_bytes()) { 1226 // We are inspecting an object's concrete class. 1227 // Short-circuit the check if the query is abstract. 1228 if (superklass->is_interface() || 1229 superklass->is_abstract()) { 1230 // Make it come out always false: 1231 this->set_req(2, phase->makecon(TypePtr::NULL_PTR)); 1232 return this; 1233 } 1234 } 1235 1236 // Check for a LoadKlass from primary supertype array. 1237 // Any nested loadklass from loadklass+con must be from the p.s. array. 1238 if (ldk2->is_DecodeNKlass()) { 1239 // Keep ldk2 as DecodeN since it could be used in CmpP below. 1240 if (ldk2->in(1)->Opcode() != Op_LoadNKlass ) 1241 return NULL; 1242 } else if (ldk2->Opcode() != Op_LoadKlass) 1243 return NULL; 1244 1245 // Verify that we understand the situation 1246 if (con2 != (intptr_t) superklass->super_check_offset()) 1247 return NULL; // Might be element-klass loading from array klass 1248 1249 // Do not fold the subtype check to an array klass pointer comparison for [V? arrays. 1250 // [QMyValue is a subtype of [LMyValue but the klass for [QMyValue is not equal to 1251 // the klass for [LMyValue. Do not bypass the klass load from the primary supertype array. 1252 if (superklass->is_obj_array_klass() && !superklass->as_array_klass()->is_elem_null_free() && 1253 superklass->as_array_klass()->element_klass()->is_inlinetype()) { 1254 return NULL; 1255 } 1256 1257 // If 'superklass' has no subklasses and is not an interface, then we are 1258 // assured that the only input which will pass the type check is 1259 // 'superklass' itself. 1260 // 1261 // We could be more liberal here, and allow the optimization on interfaces 1262 // which have a single implementor. This would require us to increase the 1263 // expressiveness of the add_dependency() mechanism. 1264 // %%% Do this after we fix TypeOopPtr: Deps are expressive enough now. 1265 1266 // Object arrays must have their base element have no subtypes 1267 while (superklass->is_obj_array_klass()) { 1268 ciType* elem = superklass->as_obj_array_klass()->element_type(); 1269 superklass = elem->as_klass(); 1270 } 1271 if (superklass->is_instance_klass()) { 1272 ciInstanceKlass* ik = superklass->as_instance_klass(); 1273 if (ik->has_subklass() || ik->is_interface()) return NULL; 1274 // Add a dependency if there is a chance that a subclass will be added later. 1275 if (!ik->is_final()) { 1276 phase->C->dependencies()->assert_leaf_type(ik); 1277 } 1278 } 1279 1280 // Bypass the dependent load, and compare directly 1281 this->set_req(1,ldk2); 1282 1283 return this; 1284 } 1285 1286 //============================================================================= 1287 //------------------------------sub-------------------------------------------- 1288 // Simplify an CmpN (compare 2 pointers) node, based on local information. 1289 // If both inputs are constants, compare them. 1290 const Type *CmpNNode::sub( const Type *t1, const Type *t2 ) const { 1291 ShouldNotReachHere(); 1292 return bottom_type(); 1293 } 1294 1295 //------------------------------Ideal------------------------------------------ 1296 Node *CmpNNode::Ideal( PhaseGVN *phase, bool can_reshape ) { 1297 return NULL; 1298 } 1299 1300 //============================================================================= 1301 //------------------------------Value------------------------------------------ 1302 // Simplify an CmpF (compare 2 floats ) node, based on local information. 1303 // If both inputs are constants, compare them. 1304 const Type* CmpFNode::Value(PhaseGVN* phase) const { 1305 const Node* in1 = in(1); 1306 const Node* in2 = in(2); 1307 // Either input is TOP ==> the result is TOP 1308 const Type* t1 = (in1 == this) ? Type::TOP : phase->type(in1); 1309 if( t1 == Type::TOP ) return Type::TOP; 1310 const Type* t2 = (in2 == this) ? Type::TOP : phase->type(in2); 1311 if( t2 == Type::TOP ) return Type::TOP; 1312 1313 // Not constants? Don't know squat - even if they are the same 1314 // value! If they are NaN's they compare to LT instead of EQ. 1315 const TypeF *tf1 = t1->isa_float_constant(); 1316 const TypeF *tf2 = t2->isa_float_constant(); 1317 if( !tf1 || !tf2 ) return TypeInt::CC; 1318 1319 // This implements the Java bytecode fcmpl, so unordered returns -1. 1320 if( tf1->is_nan() || tf2->is_nan() ) 1321 return TypeInt::CC_LT; 1322 1323 if( tf1->_f < tf2->_f ) return TypeInt::CC_LT; 1324 if( tf1->_f > tf2->_f ) return TypeInt::CC_GT; 1325 assert( tf1->_f == tf2->_f, "do not understand FP behavior" ); 1326 return TypeInt::CC_EQ; 1327 } 1328 1329 1330 //============================================================================= 1331 //------------------------------Value------------------------------------------ 1332 // Simplify an CmpD (compare 2 doubles ) node, based on local information. 1333 // If both inputs are constants, compare them. 1334 const Type* CmpDNode::Value(PhaseGVN* phase) const { 1335 const Node* in1 = in(1); 1336 const Node* in2 = in(2); 1337 // Either input is TOP ==> the result is TOP 1338 const Type* t1 = (in1 == this) ? Type::TOP : phase->type(in1); 1339 if( t1 == Type::TOP ) return Type::TOP; 1340 const Type* t2 = (in2 == this) ? Type::TOP : phase->type(in2); 1341 if( t2 == Type::TOP ) return Type::TOP; 1342 1343 // Not constants? Don't know squat - even if they are the same 1344 // value! If they are NaN's they compare to LT instead of EQ. 1345 const TypeD *td1 = t1->isa_double_constant(); 1346 const TypeD *td2 = t2->isa_double_constant(); 1347 if( !td1 || !td2 ) return TypeInt::CC; 1348 1349 // This implements the Java bytecode dcmpl, so unordered returns -1. 1350 if( td1->is_nan() || td2->is_nan() ) 1351 return TypeInt::CC_LT; 1352 1353 if( td1->_d < td2->_d ) return TypeInt::CC_LT; 1354 if( td1->_d > td2->_d ) return TypeInt::CC_GT; 1355 assert( td1->_d == td2->_d, "do not understand FP behavior" ); 1356 return TypeInt::CC_EQ; 1357 } 1358 1359 //------------------------------Ideal------------------------------------------ 1360 Node *CmpDNode::Ideal(PhaseGVN *phase, bool can_reshape){ 1361 // Check if we can change this to a CmpF and remove a ConvD2F operation. 1362 // Change (CMPD (F2D (float)) (ConD value)) 1363 // To (CMPF (float) (ConF value)) 1364 // Valid when 'value' does not lose precision as a float. 1365 // Benefits: eliminates conversion, does not require 24-bit mode 1366 1367 // NaNs prevent commuting operands. This transform works regardless of the 1368 // order of ConD and ConvF2D inputs by preserving the original order. 1369 int idx_f2d = 1; // ConvF2D on left side? 1370 if( in(idx_f2d)->Opcode() != Op_ConvF2D ) 1371 idx_f2d = 2; // No, swap to check for reversed args 1372 int idx_con = 3-idx_f2d; // Check for the constant on other input 1373 1374 if( ConvertCmpD2CmpF && 1375 in(idx_f2d)->Opcode() == Op_ConvF2D && 1376 in(idx_con)->Opcode() == Op_ConD ) { 1377 const TypeD *t2 = in(idx_con)->bottom_type()->is_double_constant(); 1378 double t2_value_as_double = t2->_d; 1379 float t2_value_as_float = (float)t2_value_as_double; 1380 if( t2_value_as_double == (double)t2_value_as_float ) { 1381 // Test value can be represented as a float 1382 // Eliminate the conversion to double and create new comparison 1383 Node *new_in1 = in(idx_f2d)->in(1); 1384 Node *new_in2 = phase->makecon( TypeF::make(t2_value_as_float) ); 1385 if( idx_f2d != 1 ) { // Must flip args to match original order 1386 Node *tmp = new_in1; 1387 new_in1 = new_in2; 1388 new_in2 = tmp; 1389 } 1390 CmpFNode *new_cmp = (Opcode() == Op_CmpD3) 1391 ? new CmpF3Node( new_in1, new_in2 ) 1392 : new CmpFNode ( new_in1, new_in2 ) ; 1393 return new_cmp; // Changed to CmpFNode 1394 } 1395 // Testing value required the precision of a double 1396 } 1397 return NULL; // No change 1398 } 1399 1400 //============================================================================= 1401 //------------------------------Value------------------------------------------ 1402 const Type* FlatArrayCheckNode::Value(PhaseGVN* phase) const { 1403 bool all_not_flat = true; 1404 for (uint i = ArrayOrKlass; i < req(); ++i) { 1405 const Type* t = phase->type(in(i)); 1406 if (t == Type::TOP) { 1407 return Type::TOP; 1408 } 1409 if (t->is_ptr()->is_flat()) { 1410 // One of the input arrays is flat, check always passes 1411 return TypeInt::CC_EQ; 1412 } else if (!t->is_ptr()->is_not_flat()) { 1413 // One of the input arrays might be flat 1414 all_not_flat = false; 1415 } 1416 } 1417 if (all_not_flat) { 1418 // None of the input arrays can be flat, check always fails 1419 return TypeInt::CC_GT; 1420 } 1421 return TypeInt::CC; 1422 } 1423 1424 //------------------------------Ideal------------------------------------------ 1425 Node* FlatArrayCheckNode::Ideal(PhaseGVN* phase, bool can_reshape) { 1426 bool changed = false; 1427 // Remove inputs that are known to be non-flat 1428 for (uint i = ArrayOrKlass; i < req(); ++i) { 1429 const Type* t = phase->type(in(i)); 1430 if (t->isa_ptr() && t->is_ptr()->is_not_flat()) { 1431 del_req(i--); 1432 changed = true; 1433 } 1434 } 1435 return changed ? this : NULL; 1436 } 1437 1438 //============================================================================= 1439 //------------------------------cc2logical------------------------------------- 1440 // Convert a condition code type to a logical type 1441 const Type *BoolTest::cc2logical( const Type *CC ) const { 1442 if( CC == Type::TOP ) return Type::TOP; 1443 if( CC->base() != Type::Int ) return TypeInt::BOOL; // Bottom or worse 1444 const TypeInt *ti = CC->is_int(); 1445 if( ti->is_con() ) { // Only 1 kind of condition codes set? 1446 // Match low order 2 bits 1447 int tmp = ((ti->get_con()&3) == (_test&3)) ? 1 : 0; 1448 if( _test & 4 ) tmp = 1-tmp; // Optionally complement result 1449 return TypeInt::make(tmp); // Boolean result 1450 } 1451 1452 if( CC == TypeInt::CC_GE ) { 1453 if( _test == ge ) return TypeInt::ONE; 1454 if( _test == lt ) return TypeInt::ZERO; 1455 } 1456 if( CC == TypeInt::CC_LE ) { 1457 if( _test == le ) return TypeInt::ONE; 1458 if( _test == gt ) return TypeInt::ZERO; 1459 } 1460 1461 return TypeInt::BOOL; 1462 } 1463 1464 //------------------------------dump_spec------------------------------------- 1465 // Print special per-node info 1466 void BoolTest::dump_on(outputStream *st) const { 1467 const char *msg[] = {"eq","gt","of","lt","ne","le","nof","ge"}; 1468 st->print("%s", msg[_test]); 1469 } 1470 1471 // Returns the logical AND of two tests (or 'never' if both tests can never be true). 1472 // For example, a test for 'le' followed by a test for 'lt' is equivalent with 'lt'. 1473 BoolTest::mask BoolTest::merge(BoolTest other) const { 1474 const mask res[illegal+1][illegal+1] = { 1475 // eq, gt, of, lt, ne, le, nof, ge, never, illegal 1476 {eq, never, illegal, never, never, eq, illegal, eq, never, illegal}, // eq 1477 {never, gt, illegal, never, gt, never, illegal, gt, never, illegal}, // gt 1478 {illegal, illegal, illegal, illegal, illegal, illegal, illegal, illegal, never, illegal}, // of 1479 {never, never, illegal, lt, lt, lt, illegal, never, never, illegal}, // lt 1480 {never, gt, illegal, lt, ne, lt, illegal, gt, never, illegal}, // ne 1481 {eq, never, illegal, lt, lt, le, illegal, eq, never, illegal}, // le 1482 {illegal, illegal, illegal, illegal, illegal, illegal, illegal, illegal, never, illegal}, // nof 1483 {eq, gt, illegal, never, gt, eq, illegal, ge, never, illegal}, // ge 1484 {never, never, never, never, never, never, never, never, never, illegal}, // never 1485 {illegal, illegal, illegal, illegal, illegal, illegal, illegal, illegal, illegal, illegal}}; // illegal 1486 return res[_test][other._test]; 1487 } 1488 1489 //============================================================================= 1490 uint BoolNode::hash() const { return (Node::hash() << 3)|(_test._test+1); } 1491 uint BoolNode::size_of() const { return sizeof(BoolNode); } 1492 1493 //------------------------------operator==------------------------------------- 1494 bool BoolNode::cmp( const Node &n ) const { 1495 const BoolNode *b = (const BoolNode *)&n; // Cast up 1496 return (_test._test == b->_test._test); 1497 } 1498 1499 //-------------------------------make_predicate-------------------------------- 1500 Node* BoolNode::make_predicate(Node* test_value, PhaseGVN* phase) { 1501 if (test_value->is_Con()) return test_value; 1502 if (test_value->is_Bool()) return test_value; 1503 if (test_value->is_CMove() && 1504 test_value->in(CMoveNode::Condition)->is_Bool()) { 1505 BoolNode* bol = test_value->in(CMoveNode::Condition)->as_Bool(); 1506 const Type* ftype = phase->type(test_value->in(CMoveNode::IfFalse)); 1507 const Type* ttype = phase->type(test_value->in(CMoveNode::IfTrue)); 1508 if (ftype == TypeInt::ZERO && !TypeInt::ZERO->higher_equal(ttype)) { 1509 return bol; 1510 } else if (ttype == TypeInt::ZERO && !TypeInt::ZERO->higher_equal(ftype)) { 1511 return phase->transform( bol->negate(phase) ); 1512 } 1513 // Else fall through. The CMove gets in the way of the test. 1514 // It should be the case that make_predicate(bol->as_int_value()) == bol. 1515 } 1516 Node* cmp = new CmpINode(test_value, phase->intcon(0)); 1517 cmp = phase->transform(cmp); 1518 Node* bol = new BoolNode(cmp, BoolTest::ne); 1519 return phase->transform(bol); 1520 } 1521 1522 //--------------------------------as_int_value--------------------------------- 1523 Node* BoolNode::as_int_value(PhaseGVN* phase) { 1524 // Inverse to make_predicate. The CMove probably boils down to a Conv2B. 1525 Node* cmov = CMoveNode::make(NULL, this, 1526 phase->intcon(0), phase->intcon(1), 1527 TypeInt::BOOL); 1528 return phase->transform(cmov); 1529 } 1530 1531 //----------------------------------negate------------------------------------- 1532 BoolNode* BoolNode::negate(PhaseGVN* phase) { 1533 return new BoolNode(in(1), _test.negate()); 1534 } 1535 1536 // Change "bool eq/ne (cmp (add/sub A B) C)" into false/true if add/sub 1537 // overflows and we can prove that C is not in the two resulting ranges. 1538 // This optimization is similar to the one performed by CmpUNode::Value(). 1539 Node* BoolNode::fold_cmpI(PhaseGVN* phase, SubNode* cmp, Node* cmp1, int cmp_op, 1540 int cmp1_op, const TypeInt* cmp2_type) { 1541 // Only optimize eq/ne integer comparison of add/sub 1542 if((_test._test == BoolTest::eq || _test._test == BoolTest::ne) && 1543 (cmp_op == Op_CmpI) && (cmp1_op == Op_AddI || cmp1_op == Op_SubI)) { 1544 // Skip cases were inputs of add/sub are not integers or of bottom type 1545 const TypeInt* r0 = phase->type(cmp1->in(1))->isa_int(); 1546 const TypeInt* r1 = phase->type(cmp1->in(2))->isa_int(); 1547 if ((r0 != NULL) && (r0 != TypeInt::INT) && 1548 (r1 != NULL) && (r1 != TypeInt::INT) && 1549 (cmp2_type != TypeInt::INT)) { 1550 // Compute exact (long) type range of add/sub result 1551 jlong lo_long = r0->_lo; 1552 jlong hi_long = r0->_hi; 1553 if (cmp1_op == Op_AddI) { 1554 lo_long += r1->_lo; 1555 hi_long += r1->_hi; 1556 } else { 1557 lo_long -= r1->_hi; 1558 hi_long -= r1->_lo; 1559 } 1560 // Check for over-/underflow by casting to integer 1561 int lo_int = (int)lo_long; 1562 int hi_int = (int)hi_long; 1563 bool underflow = lo_long != (jlong)lo_int; 1564 bool overflow = hi_long != (jlong)hi_int; 1565 if ((underflow != overflow) && (hi_int < lo_int)) { 1566 // Overflow on one boundary, compute resulting type ranges: 1567 // tr1 [MIN_INT, hi_int] and tr2 [lo_int, MAX_INT] 1568 int w = MAX2(r0->_widen, r1->_widen); // _widen does not matter here 1569 const TypeInt* tr1 = TypeInt::make(min_jint, hi_int, w); 1570 const TypeInt* tr2 = TypeInt::make(lo_int, max_jint, w); 1571 // Compare second input of cmp to both type ranges 1572 const Type* sub_tr1 = cmp->sub(tr1, cmp2_type); 1573 const Type* sub_tr2 = cmp->sub(tr2, cmp2_type); 1574 if (sub_tr1 == TypeInt::CC_LT && sub_tr2 == TypeInt::CC_GT) { 1575 // The result of the add/sub will never equal cmp2. Replace BoolNode 1576 // by false (0) if it tests for equality and by true (1) otherwise. 1577 return ConINode::make((_test._test == BoolTest::eq) ? 0 : 1); 1578 } 1579 } 1580 } 1581 } 1582 return NULL; 1583 } 1584 1585 static bool is_counted_loop_cmp(Node *cmp) { 1586 Node *n = cmp->in(1)->in(1); 1587 return n != NULL && 1588 n->is_Phi() && 1589 n->in(0) != NULL && 1590 n->in(0)->is_CountedLoop() && 1591 n->in(0)->as_CountedLoop()->phi() == n; 1592 } 1593 1594 //------------------------------Ideal------------------------------------------ 1595 Node *BoolNode::Ideal(PhaseGVN *phase, bool can_reshape) { 1596 // Change "bool tst (cmp con x)" into "bool ~tst (cmp x con)". 1597 // This moves the constant to the right. Helps value-numbering. 1598 Node *cmp = in(1); 1599 if( !cmp->is_Sub() ) return NULL; 1600 int cop = cmp->Opcode(); 1601 if( cop == Op_FastLock || cop == Op_FastUnlock || cmp->is_SubTypeCheck()) return NULL; 1602 Node *cmp1 = cmp->in(1); 1603 Node *cmp2 = cmp->in(2); 1604 if( !cmp1 ) return NULL; 1605 1606 if (_test._test == BoolTest::overflow || _test._test == BoolTest::no_overflow) { 1607 return NULL; 1608 } 1609 1610 const int cmp1_op = cmp1->Opcode(); 1611 const int cmp2_op = cmp2->Opcode(); 1612 1613 // Constant on left? 1614 Node *con = cmp1; 1615 // Move constants to the right of compare's to canonicalize. 1616 // Do not muck with Opaque1 nodes, as this indicates a loop 1617 // guard that cannot change shape. 1618 if( con->is_Con() && !cmp2->is_Con() && cmp2_op != Op_Opaque1 && 1619 // Because of NaN's, CmpD and CmpF are not commutative 1620 cop != Op_CmpD && cop != Op_CmpF && 1621 // Protect against swapping inputs to a compare when it is used by a 1622 // counted loop exit, which requires maintaining the loop-limit as in(2) 1623 !is_counted_loop_exit_test() ) { 1624 // Ok, commute the constant to the right of the cmp node. 1625 // Clone the Node, getting a new Node of the same class 1626 cmp = cmp->clone(); 1627 // Swap inputs to the clone 1628 cmp->swap_edges(1, 2); 1629 cmp = phase->transform( cmp ); 1630 return new BoolNode( cmp, _test.commute() ); 1631 } 1632 1633 // Change "bool eq/ne (cmp (and X 16) 16)" into "bool ne/eq (cmp (and X 16) 0)". 1634 if (cop == Op_CmpI && 1635 (_test._test == BoolTest::eq || _test._test == BoolTest::ne) && 1636 cmp1_op == Op_AndI && cmp2_op == Op_ConI && 1637 cmp1->in(2)->Opcode() == Op_ConI) { 1638 const TypeInt *t12 = phase->type(cmp2)->isa_int(); 1639 const TypeInt *t112 = phase->type(cmp1->in(2))->isa_int(); 1640 if (t12 && t12->is_con() && t112 && t112->is_con() && 1641 t12->get_con() == t112->get_con() && is_power_of_2(t12->get_con())) { 1642 Node *ncmp = phase->transform(new CmpINode(cmp1, phase->intcon(0))); 1643 return new BoolNode(ncmp, _test.negate()); 1644 } 1645 } 1646 1647 // Same for long type: change "bool eq/ne (cmp (and X 16) 16)" into "bool ne/eq (cmp (and X 16) 0)". 1648 if (cop == Op_CmpL && 1649 (_test._test == BoolTest::eq || _test._test == BoolTest::ne) && 1650 cmp1_op == Op_AndL && cmp2_op == Op_ConL && 1651 cmp1->in(2)->Opcode() == Op_ConL) { 1652 const TypeLong *t12 = phase->type(cmp2)->isa_long(); 1653 const TypeLong *t112 = phase->type(cmp1->in(2))->isa_long(); 1654 if (t12 && t12->is_con() && t112 && t112->is_con() && 1655 t12->get_con() == t112->get_con() && is_power_of_2(t12->get_con())) { 1656 Node *ncmp = phase->transform(new CmpLNode(cmp1, phase->longcon(0))); 1657 return new BoolNode(ncmp, _test.negate()); 1658 } 1659 } 1660 1661 // Change "cmp (add X min_jint) (add Y min_jint)" into "cmpu X Y" 1662 // and "cmp (add X min_jint) c" into "cmpu X (c + min_jint)" 1663 if (cop == Op_CmpI && 1664 cmp1_op == Op_AddI && 1665 phase->type(cmp1->in(2)) == TypeInt::MIN) { 1666 if (cmp2_op == Op_ConI) { 1667 Node* ncmp2 = phase->intcon(java_add(cmp2->get_int(), min_jint)); 1668 Node* ncmp = phase->transform(new CmpUNode(cmp1->in(1), ncmp2)); 1669 return new BoolNode(ncmp, _test._test); 1670 } else if (cmp2_op == Op_AddI && 1671 phase->type(cmp2->in(2)) == TypeInt::MIN) { 1672 Node* ncmp = phase->transform(new CmpUNode(cmp1->in(1), cmp2->in(1))); 1673 return new BoolNode(ncmp, _test._test); 1674 } 1675 } 1676 1677 // Change "cmp (add X min_jlong) (add Y min_jlong)" into "cmpu X Y" 1678 // and "cmp (add X min_jlong) c" into "cmpu X (c + min_jlong)" 1679 if (cop == Op_CmpL && 1680 cmp1_op == Op_AddL && 1681 phase->type(cmp1->in(2)) == TypeLong::MIN) { 1682 if (cmp2_op == Op_ConL) { 1683 Node* ncmp2 = phase->longcon(java_add(cmp2->get_long(), min_jlong)); 1684 Node* ncmp = phase->transform(new CmpULNode(cmp1->in(1), ncmp2)); 1685 return new BoolNode(ncmp, _test._test); 1686 } else if (cmp2_op == Op_AddL && 1687 phase->type(cmp2->in(2)) == TypeLong::MIN) { 1688 Node* ncmp = phase->transform(new CmpULNode(cmp1->in(1), cmp2->in(1))); 1689 return new BoolNode(ncmp, _test._test); 1690 } 1691 } 1692 1693 // Change "bool eq/ne (cmp (xor X 1) 0)" into "bool ne/eq (cmp X 0)". 1694 // The XOR-1 is an idiom used to flip the sense of a bool. We flip the 1695 // test instead. 1696 const TypeInt* cmp2_type = phase->type(cmp2)->isa_int(); 1697 if (cmp2_type == NULL) return NULL; 1698 Node* j_xor = cmp1; 1699 if( cmp2_type == TypeInt::ZERO && 1700 cmp1_op == Op_XorI && 1701 j_xor->in(1) != j_xor && // An xor of itself is dead 1702 phase->type( j_xor->in(1) ) == TypeInt::BOOL && 1703 phase->type( j_xor->in(2) ) == TypeInt::ONE && 1704 (_test._test == BoolTest::eq || 1705 _test._test == BoolTest::ne) ) { 1706 Node *ncmp = phase->transform(new CmpINode(j_xor->in(1),cmp2)); 1707 return new BoolNode( ncmp, _test.negate() ); 1708 } 1709 1710 // Change ((x & m) u<= m) or ((m & x) u<= m) to always true 1711 // Same with ((x & m) u< m+1) and ((m & x) u< m+1) 1712 if (cop == Op_CmpU && 1713 cmp1_op == Op_AndI) { 1714 Node* bound = NULL; 1715 if (_test._test == BoolTest::le) { 1716 bound = cmp2; 1717 } else if (_test._test == BoolTest::lt && 1718 cmp2->Opcode() == Op_AddI && 1719 cmp2->in(2)->find_int_con(0) == 1) { 1720 bound = cmp2->in(1); 1721 } 1722 if (cmp1->in(2) == bound || cmp1->in(1) == bound) { 1723 return ConINode::make(1); 1724 } 1725 } 1726 1727 // Change ((x & (m - 1)) u< m) into (m > 0) 1728 // This is the off-by-one variant of the above 1729 if (cop == Op_CmpU && 1730 _test._test == BoolTest::lt && 1731 cmp1_op == Op_AndI) { 1732 Node* l = cmp1->in(1); 1733 Node* r = cmp1->in(2); 1734 for (int repeat = 0; repeat < 2; repeat++) { 1735 bool match = r->Opcode() == Op_AddI && r->in(2)->find_int_con(0) == -1 && 1736 r->in(1) == cmp2; 1737 if (match) { 1738 // arraylength known to be non-negative, so a (arraylength != 0) is sufficient, 1739 // but to be compatible with the array range check pattern, use (arraylength u> 0) 1740 Node* ncmp = cmp2->Opcode() == Op_LoadRange 1741 ? phase->transform(new CmpUNode(cmp2, phase->intcon(0))) 1742 : phase->transform(new CmpINode(cmp2, phase->intcon(0))); 1743 return new BoolNode(ncmp, BoolTest::gt); 1744 } else { 1745 // commute and try again 1746 l = cmp1->in(2); 1747 r = cmp1->in(1); 1748 } 1749 } 1750 } 1751 1752 // Change x u< 1 or x u<= 0 to x == 0 1753 if (cop == Op_CmpU && 1754 cmp1_op != Op_LoadRange && 1755 ((_test._test == BoolTest::lt && 1756 cmp2->find_int_con(-1) == 1) || 1757 (_test._test == BoolTest::le && 1758 cmp2->find_int_con(-1) == 0))) { 1759 Node* ncmp = phase->transform(new CmpINode(cmp1, phase->intcon(0))); 1760 return new BoolNode(ncmp, BoolTest::eq); 1761 } 1762 1763 // Change (arraylength <= 0) or (arraylength == 0) 1764 // into (arraylength u<= 0) 1765 // Also change (arraylength != 0) into (arraylength u> 0) 1766 // The latter version matches the code pattern generated for 1767 // array range checks, which will more likely be optimized later. 1768 if (cop == Op_CmpI && 1769 cmp1_op == Op_LoadRange && 1770 cmp2->find_int_con(-1) == 0) { 1771 if (_test._test == BoolTest::le || _test._test == BoolTest::eq) { 1772 Node* ncmp = phase->transform(new CmpUNode(cmp1, cmp2)); 1773 return new BoolNode(ncmp, BoolTest::le); 1774 } else if (_test._test == BoolTest::ne) { 1775 Node* ncmp = phase->transform(new CmpUNode(cmp1, cmp2)); 1776 return new BoolNode(ncmp, BoolTest::gt); 1777 } 1778 } 1779 1780 // Change "bool eq/ne (cmp (Conv2B X) 0)" into "bool eq/ne (cmp X 0)". 1781 // This is a standard idiom for branching on a boolean value. 1782 Node *c2b = cmp1; 1783 if( cmp2_type == TypeInt::ZERO && 1784 cmp1_op == Op_Conv2B && 1785 (_test._test == BoolTest::eq || 1786 _test._test == BoolTest::ne) ) { 1787 Node *ncmp = phase->transform(phase->type(c2b->in(1))->isa_int() 1788 ? (Node*)new CmpINode(c2b->in(1),cmp2) 1789 : (Node*)new CmpPNode(c2b->in(1),phase->makecon(TypePtr::NULL_PTR)) 1790 ); 1791 return new BoolNode( ncmp, _test._test ); 1792 } 1793 1794 // Comparing a SubI against a zero is equal to comparing the SubI 1795 // arguments directly. This only works for eq and ne comparisons 1796 // due to possible integer overflow. 1797 if ((_test._test == BoolTest::eq || _test._test == BoolTest::ne) && 1798 (cop == Op_CmpI) && 1799 (cmp1_op == Op_SubI) && 1800 ( cmp2_type == TypeInt::ZERO ) ) { 1801 Node *ncmp = phase->transform( new CmpINode(cmp1->in(1),cmp1->in(2))); 1802 return new BoolNode( ncmp, _test._test ); 1803 } 1804 1805 // Same as above but with and AddI of a constant 1806 if ((_test._test == BoolTest::eq || _test._test == BoolTest::ne) && 1807 cop == Op_CmpI && 1808 cmp1_op == Op_AddI && 1809 cmp1->in(2) != NULL && 1810 phase->type(cmp1->in(2))->isa_int() && 1811 phase->type(cmp1->in(2))->is_int()->is_con() && 1812 cmp2_type == TypeInt::ZERO && 1813 !is_counted_loop_cmp(cmp) // modifying the exit test of a counted loop messes the counted loop shape 1814 ) { 1815 const TypeInt* cmp1_in2 = phase->type(cmp1->in(2))->is_int(); 1816 Node *ncmp = phase->transform( new CmpINode(cmp1->in(1),phase->intcon(-cmp1_in2->_hi))); 1817 return new BoolNode( ncmp, _test._test ); 1818 } 1819 1820 // Change "bool eq/ne (cmp (phi (X -X) 0))" into "bool eq/ne (cmp X 0)" 1821 // since zero check of conditional negation of an integer is equal to 1822 // zero check of the integer directly. 1823 if ((_test._test == BoolTest::eq || _test._test == BoolTest::ne) && 1824 (cop == Op_CmpI) && 1825 (cmp2_type == TypeInt::ZERO) && 1826 (cmp1_op == Op_Phi)) { 1827 // There should be a diamond phi with true path at index 1 or 2 1828 PhiNode *phi = cmp1->as_Phi(); 1829 int idx_true = phi->is_diamond_phi(); 1830 if (idx_true != 0) { 1831 // True input is in(idx_true) while false input is in(3 - idx_true) 1832 Node *tin = phi->in(idx_true); 1833 Node *fin = phi->in(3 - idx_true); 1834 if ((tin->Opcode() == Op_SubI) && 1835 (phase->type(tin->in(1)) == TypeInt::ZERO) && 1836 (tin->in(2) == fin)) { 1837 // Found conditional negation at true path, create a new CmpINode without that 1838 Node *ncmp = phase->transform(new CmpINode(fin, cmp2)); 1839 return new BoolNode(ncmp, _test._test); 1840 } 1841 if ((fin->Opcode() == Op_SubI) && 1842 (phase->type(fin->in(1)) == TypeInt::ZERO) && 1843 (fin->in(2) == tin)) { 1844 // Found conditional negation at false path, create a new CmpINode without that 1845 Node *ncmp = phase->transform(new CmpINode(tin, cmp2)); 1846 return new BoolNode(ncmp, _test._test); 1847 } 1848 } 1849 } 1850 1851 // Change (-A vs 0) into (A vs 0) by commuting the test. Disallow in the 1852 // most general case because negating 0x80000000 does nothing. Needed for 1853 // the CmpF3/SubI/CmpI idiom. 1854 if( cop == Op_CmpI && 1855 cmp1_op == Op_SubI && 1856 cmp2_type == TypeInt::ZERO && 1857 phase->type( cmp1->in(1) ) == TypeInt::ZERO && 1858 phase->type( cmp1->in(2) )->higher_equal(TypeInt::SYMINT) ) { 1859 Node *ncmp = phase->transform( new CmpINode(cmp1->in(2),cmp2)); 1860 return new BoolNode( ncmp, _test.commute() ); 1861 } 1862 1863 // Try to optimize signed integer comparison 1864 return fold_cmpI(phase, cmp->as_Sub(), cmp1, cop, cmp1_op, cmp2_type); 1865 1866 // The transformation below is not valid for either signed or unsigned 1867 // comparisons due to wraparound concerns at MAX_VALUE and MIN_VALUE. 1868 // This transformation can be resurrected when we are able to 1869 // make inferences about the range of values being subtracted from 1870 // (or added to) relative to the wraparound point. 1871 // 1872 // // Remove +/-1's if possible. 1873 // // "X <= Y-1" becomes "X < Y" 1874 // // "X+1 <= Y" becomes "X < Y" 1875 // // "X < Y+1" becomes "X <= Y" 1876 // // "X-1 < Y" becomes "X <= Y" 1877 // // Do not this to compares off of the counted-loop-end. These guys are 1878 // // checking the trip counter and they want to use the post-incremented 1879 // // counter. If they use the PRE-incremented counter, then the counter has 1880 // // to be incremented in a private block on a loop backedge. 1881 // if( du && du->cnt(this) && du->out(this)[0]->Opcode() == Op_CountedLoopEnd ) 1882 // return NULL; 1883 // #ifndef PRODUCT 1884 // // Do not do this in a wash GVN pass during verification. 1885 // // Gets triggered by too many simple optimizations to be bothered with 1886 // // re-trying it again and again. 1887 // if( !phase->allow_progress() ) return NULL; 1888 // #endif 1889 // // Not valid for unsigned compare because of corner cases in involving zero. 1890 // // For example, replacing "X-1 <u Y" with "X <=u Y" fails to throw an 1891 // // exception in case X is 0 (because 0-1 turns into 4billion unsigned but 1892 // // "0 <=u Y" is always true). 1893 // if( cmp->Opcode() == Op_CmpU ) return NULL; 1894 // int cmp2_op = cmp2->Opcode(); 1895 // if( _test._test == BoolTest::le ) { 1896 // if( cmp1_op == Op_AddI && 1897 // phase->type( cmp1->in(2) ) == TypeInt::ONE ) 1898 // return clone_cmp( cmp, cmp1->in(1), cmp2, phase, BoolTest::lt ); 1899 // else if( cmp2_op == Op_AddI && 1900 // phase->type( cmp2->in(2) ) == TypeInt::MINUS_1 ) 1901 // return clone_cmp( cmp, cmp1, cmp2->in(1), phase, BoolTest::lt ); 1902 // } else if( _test._test == BoolTest::lt ) { 1903 // if( cmp1_op == Op_AddI && 1904 // phase->type( cmp1->in(2) ) == TypeInt::MINUS_1 ) 1905 // return clone_cmp( cmp, cmp1->in(1), cmp2, phase, BoolTest::le ); 1906 // else if( cmp2_op == Op_AddI && 1907 // phase->type( cmp2->in(2) ) == TypeInt::ONE ) 1908 // return clone_cmp( cmp, cmp1, cmp2->in(1), phase, BoolTest::le ); 1909 // } 1910 } 1911 1912 //------------------------------Value------------------------------------------ 1913 // Simplify a Bool (convert condition codes to boolean (1 or 0)) node, 1914 // based on local information. If the input is constant, do it. 1915 const Type* BoolNode::Value(PhaseGVN* phase) const { 1916 return _test.cc2logical( phase->type( in(1) ) ); 1917 } 1918 1919 #ifndef PRODUCT 1920 //------------------------------dump_spec-------------------------------------- 1921 // Dump special per-node info 1922 void BoolNode::dump_spec(outputStream *st) const { 1923 st->print("["); 1924 _test.dump_on(st); 1925 st->print("]"); 1926 } 1927 1928 //-------------------------------related--------------------------------------- 1929 // A BoolNode's related nodes are all of its data inputs, and all of its 1930 // outputs until control nodes are hit, which are included. In compact 1931 // representation, inputs till level 3 and immediate outputs are included. 1932 void BoolNode::related(GrowableArray<Node*> *in_rel, GrowableArray<Node*> *out_rel, bool compact) const { 1933 if (compact) { 1934 this->collect_nodes(in_rel, 3, false, true); 1935 this->collect_nodes(out_rel, -1, false, false); 1936 } else { 1937 this->collect_nodes_in_all_data(in_rel, false); 1938 this->collect_nodes_out_all_ctrl_boundary(out_rel); 1939 } 1940 } 1941 #endif 1942 1943 //----------------------is_counted_loop_exit_test------------------------------ 1944 // Returns true if node is used by a counted loop node. 1945 bool BoolNode::is_counted_loop_exit_test() { 1946 for( DUIterator_Fast imax, i = fast_outs(imax); i < imax; i++ ) { 1947 Node* use = fast_out(i); 1948 if (use->is_CountedLoopEnd()) { 1949 return true; 1950 } 1951 } 1952 return false; 1953 } 1954 1955 //============================================================================= 1956 //------------------------------Value------------------------------------------ 1957 const Type* AbsNode::Value(PhaseGVN* phase) const { 1958 const Type* t1 = phase->type(in(1)); 1959 if (t1 == Type::TOP) return Type::TOP; 1960 1961 switch (t1->base()) { 1962 case Type::Int: { 1963 const TypeInt* ti = t1->is_int(); 1964 if (ti->is_con()) { 1965 return TypeInt::make(uabs(ti->get_con())); 1966 } 1967 break; 1968 } 1969 case Type::Long: { 1970 const TypeLong* tl = t1->is_long(); 1971 if (tl->is_con()) { 1972 return TypeLong::make(uabs(tl->get_con())); 1973 } 1974 break; 1975 } 1976 case Type::FloatCon: 1977 return TypeF::make(abs(t1->getf())); 1978 case Type::DoubleCon: 1979 return TypeD::make(abs(t1->getd())); 1980 default: 1981 break; 1982 } 1983 1984 return bottom_type(); 1985 } 1986 1987 //------------------------------Identity---------------------------------------- 1988 Node* AbsNode::Identity(PhaseGVN* phase) { 1989 Node* in1 = in(1); 1990 // No need to do abs for non-negative values 1991 if (phase->type(in1)->higher_equal(TypeInt::POS) || 1992 phase->type(in1)->higher_equal(TypeLong::POS)) { 1993 return in1; 1994 } 1995 // Convert "abs(abs(x))" into "abs(x)" 1996 if (in1->Opcode() == Opcode()) { 1997 return in1; 1998 } 1999 return this; 2000 } 2001 2002 //------------------------------Ideal------------------------------------------ 2003 Node* AbsNode::Ideal(PhaseGVN* phase, bool can_reshape) { 2004 Node* in1 = in(1); 2005 // Convert "abs(0-x)" into "abs(x)" 2006 if (in1->is_Sub() && phase->type(in1->in(1))->is_zero_type()) { 2007 set_req_X(1, in1->in(2), phase); 2008 return this; 2009 } 2010 return NULL; 2011 } 2012 2013 //============================================================================= 2014 //------------------------------Value------------------------------------------ 2015 // Compute sqrt 2016 const Type* SqrtDNode::Value(PhaseGVN* phase) const { 2017 const Type *t1 = phase->type( in(1) ); 2018 if( t1 == Type::TOP ) return Type::TOP; 2019 if( t1->base() != Type::DoubleCon ) return Type::DOUBLE; 2020 double d = t1->getd(); 2021 if( d < 0.0 ) return Type::DOUBLE; 2022 return TypeD::make( sqrt( d ) ); 2023 } 2024 2025 const Type* SqrtFNode::Value(PhaseGVN* phase) const { 2026 const Type *t1 = phase->type( in(1) ); 2027 if( t1 == Type::TOP ) return Type::TOP; 2028 if( t1->base() != Type::FloatCon ) return Type::FLOAT; 2029 float f = t1->getf(); 2030 if( f < 0.0f ) return Type::FLOAT; 2031 return TypeF::make( (float)sqrt( (double)f ) ); 2032 }