1 /* 2 * Copyright (c) 1997, 2023, 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/opaquenode.hpp" 38 #include "opto/opcodes.hpp" 39 #include "opto/phaseX.hpp" 40 #include "opto/subnode.hpp" 41 #include "runtime/sharedRuntime.hpp" 42 #include "utilities/reverse_bits.hpp" 43 44 // Portions of code courtesy of Clifford Click 45 46 // Optimization - Graph Style 47 48 #include "math.h" 49 50 //============================================================================= 51 //------------------------------Identity--------------------------------------- 52 // If right input is a constant 0, return the left input. 53 Node* SubNode::Identity(PhaseGVN* phase) { 54 assert(in(1) != this, "Must already have called Value"); 55 assert(in(2) != this, "Must already have called Value"); 56 57 // Remove double negation 58 const Type *zero = add_id(); 59 if( phase->type( in(1) )->higher_equal( zero ) && 60 in(2)->Opcode() == Opcode() && 61 phase->type( in(2)->in(1) )->higher_equal( zero ) ) { 62 return in(2)->in(2); 63 } 64 65 // Convert "(X+Y) - Y" into X and "(X+Y) - X" into Y 66 if (in(1)->Opcode() == Op_AddI || in(1)->Opcode() == Op_AddL) { 67 if (in(1)->in(2) == in(2)) { 68 return in(1)->in(1); 69 } 70 if (in(1)->in(1) == in(2)) { 71 return in(1)->in(2); 72 } 73 } 74 75 return ( phase->type( in(2) )->higher_equal( zero ) ) ? in(1) : this; 76 } 77 78 //------------------------------Value------------------------------------------ 79 // A subtract node differences it's two inputs. 80 const Type* SubNode::Value_common(PhaseValues* phase) const { 81 const Node* in1 = in(1); 82 const Node* in2 = in(2); 83 // Either input is TOP ==> the result is TOP 84 const Type* t1 = (in1 == this) ? Type::TOP : phase->type(in1); 85 if( t1 == Type::TOP ) return Type::TOP; 86 const Type* t2 = (in2 == this) ? Type::TOP : phase->type(in2); 87 if( t2 == Type::TOP ) return Type::TOP; 88 89 // Not correct for SubFnode and AddFNode (must check for infinity) 90 // Equal? Subtract is zero 91 if (in1->eqv_uncast(in2)) return add_id(); 92 93 // Either input is BOTTOM ==> the result is the local BOTTOM 94 if( t1 == Type::BOTTOM || t2 == Type::BOTTOM ) 95 return bottom_type(); 96 97 return nullptr; 98 } 99 100 const Type* SubNode::Value(PhaseGVN* phase) const { 101 const Type* t = Value_common(phase); 102 if (t != nullptr) { 103 return t; 104 } 105 const Type* t1 = phase->type(in(1)); 106 const Type* t2 = phase->type(in(2)); 107 return sub(t1,t2); // Local flavor of type subtraction 108 109 } 110 111 SubNode* SubNode::make(Node* in1, Node* in2, BasicType bt) { 112 switch (bt) { 113 case T_INT: 114 return new SubINode(in1, in2); 115 case T_LONG: 116 return new SubLNode(in1, in2); 117 default: 118 fatal("Not implemented for %s", type2name(bt)); 119 } 120 return nullptr; 121 } 122 123 //============================================================================= 124 //------------------------------Helper function-------------------------------- 125 126 static bool is_cloop_increment(Node* inc) { 127 precond(inc->Opcode() == Op_AddI || inc->Opcode() == Op_AddL); 128 129 if (!inc->in(1)->is_Phi()) { 130 return false; 131 } 132 const PhiNode* phi = inc->in(1)->as_Phi(); 133 134 if (!phi->region()->is_CountedLoop()) { 135 return false; 136 } 137 138 return inc == phi->region()->as_CountedLoop()->incr(); 139 } 140 141 // Given the expression '(x + C) - v', or 142 // 'v - (x + C)', we examine nodes '+' and 'v': 143 // 144 // 1. Do not convert if '+' is a counted-loop increment, because the '-' is 145 // loop invariant and converting extends the live-range of 'x' to overlap 146 // with the '+', forcing another register to be used in the loop. 147 // 148 // 2. Do not convert if 'v' is a counted-loop induction variable, because 149 // 'x' might be invariant. 150 // 151 static bool ok_to_convert(Node* inc, Node* var) { 152 return !(is_cloop_increment(inc) || var->is_cloop_ind_var()); 153 } 154 155 //------------------------------Ideal------------------------------------------ 156 Node *SubINode::Ideal(PhaseGVN *phase, bool can_reshape){ 157 Node *in1 = in(1); 158 Node *in2 = in(2); 159 uint op1 = in1->Opcode(); 160 uint op2 = in2->Opcode(); 161 162 #ifdef ASSERT 163 // Check for dead loop 164 if ((in1 == this) || (in2 == this) || 165 ((op1 == Op_AddI || op1 == Op_SubI) && 166 ((in1->in(1) == this) || (in1->in(2) == this) || 167 (in1->in(1) == in1) || (in1->in(2) == in1)))) { 168 assert(false, "dead loop in SubINode::Ideal"); 169 } 170 #endif 171 172 const Type *t2 = phase->type( in2 ); 173 if( t2 == Type::TOP ) return nullptr; 174 // Convert "x-c0" into "x+ -c0". 175 if( t2->base() == Type::Int ){ // Might be bottom or top... 176 const TypeInt *i = t2->is_int(); 177 if( i->is_con() ) 178 return new AddINode(in1, phase->intcon(java_negate(i->get_con()))); 179 } 180 181 // Convert "(x+c0) - y" into (x-y) + c0" 182 // Do not collapse (x+c0)-y if "+" is a loop increment or 183 // if "y" is a loop induction variable. 184 if( op1 == Op_AddI && ok_to_convert(in1, in2) ) { 185 const Type *tadd = phase->type( in1->in(2) ); 186 if( tadd->singleton() && tadd != Type::TOP ) { 187 Node *sub2 = phase->transform( new SubINode( in1->in(1), in2 )); 188 return new AddINode( sub2, in1->in(2) ); 189 } 190 } 191 192 // Convert "x - (y+c0)" into "(x-y) - c0" AND 193 // Convert "c1 - (y+c0)" into "(c1-c0) - y" 194 // Need the same check as in above optimization but reversed. 195 if (op2 == Op_AddI 196 && ok_to_convert(in2, in1) 197 && in2->in(2)->Opcode() == Op_ConI) { 198 jint c0 = phase->type(in2->in(2))->isa_int()->get_con(); 199 Node* in21 = in2->in(1); 200 if (in1->Opcode() == Op_ConI) { 201 // Match c1 202 jint c1 = phase->type(in1)->isa_int()->get_con(); 203 Node* sub2 = phase->intcon(java_subtract(c1, c0)); 204 return new SubINode(sub2, in21); 205 } else { 206 // Match x 207 Node* sub2 = phase->transform(new SubINode(in1, in21)); 208 Node* neg_c0 = phase->intcon(java_negate(c0)); 209 return new AddINode(sub2, neg_c0); 210 } 211 } 212 213 const Type *t1 = phase->type( in1 ); 214 if( t1 == Type::TOP ) return nullptr; 215 216 #ifdef ASSERT 217 // Check for dead loop 218 if ((op2 == Op_AddI || op2 == Op_SubI) && 219 ((in2->in(1) == this) || (in2->in(2) == this) || 220 (in2->in(1) == in2) || (in2->in(2) == in2))) { 221 assert(false, "dead loop in SubINode::Ideal"); 222 } 223 #endif 224 225 // Convert "x - (x+y)" into "-y" 226 if (op2 == Op_AddI && in1 == in2->in(1)) { 227 return new SubINode(phase->intcon(0), in2->in(2)); 228 } 229 // Convert "(x-y) - x" into "-y" 230 if (op1 == Op_SubI && in1->in(1) == in2) { 231 return new SubINode(phase->intcon(0), in1->in(2)); 232 } 233 // Convert "x - (y+x)" into "-y" 234 if (op2 == Op_AddI && in1 == in2->in(2)) { 235 return new SubINode(phase->intcon(0), in2->in(1)); 236 } 237 238 // Convert "0 - (x-y)" into "y-x", leave the double negation "-(-y)" to SubNode::Identity(). 239 if (t1 == TypeInt::ZERO && op2 == Op_SubI && phase->type(in2->in(1)) != TypeInt::ZERO) { 240 return new SubINode(in2->in(2), in2->in(1)); 241 } 242 243 // Convert "0 - (x+con)" into "-con-x" 244 jint con; 245 if( t1 == TypeInt::ZERO && op2 == Op_AddI && 246 (con = in2->in(2)->find_int_con(0)) != 0 ) 247 return new SubINode( phase->intcon(-con), in2->in(1) ); 248 249 // Convert "(X+A) - (X+B)" into "A - B" 250 if( op1 == Op_AddI && op2 == Op_AddI && in1->in(1) == in2->in(1) ) 251 return new SubINode( in1->in(2), in2->in(2) ); 252 253 // Convert "(A+X) - (B+X)" into "A - B" 254 if( op1 == Op_AddI && op2 == Op_AddI && in1->in(2) == in2->in(2) ) 255 return new SubINode( in1->in(1), in2->in(1) ); 256 257 // Convert "(A+X) - (X+B)" into "A - B" 258 if( op1 == Op_AddI && op2 == Op_AddI && in1->in(2) == in2->in(1) ) 259 return new SubINode( in1->in(1), in2->in(2) ); 260 261 // Convert "(X+A) - (B+X)" into "A - B" 262 if( op1 == Op_AddI && op2 == Op_AddI && in1->in(1) == in2->in(2) ) 263 return new SubINode( in1->in(2), in2->in(1) ); 264 265 // Convert "A-(B-C)" into (A+C)-B", since add is commutative and generally 266 // nicer to optimize than subtract. 267 if( op2 == Op_SubI && in2->outcnt() == 1) { 268 Node *add1 = phase->transform( new AddINode( in1, in2->in(2) ) ); 269 return new SubINode( add1, in2->in(1) ); 270 } 271 272 // Associative 273 if (op1 == Op_MulI && op2 == Op_MulI) { 274 Node* sub_in1 = nullptr; 275 Node* sub_in2 = nullptr; 276 Node* mul_in = nullptr; 277 278 if (in1->in(1) == in2->in(1)) { 279 // Convert "a*b-a*c into a*(b-c) 280 sub_in1 = in1->in(2); 281 sub_in2 = in2->in(2); 282 mul_in = in1->in(1); 283 } else if (in1->in(2) == in2->in(1)) { 284 // Convert a*b-b*c into b*(a-c) 285 sub_in1 = in1->in(1); 286 sub_in2 = in2->in(2); 287 mul_in = in1->in(2); 288 } else if (in1->in(2) == in2->in(2)) { 289 // Convert a*c-b*c into (a-b)*c 290 sub_in1 = in1->in(1); 291 sub_in2 = in2->in(1); 292 mul_in = in1->in(2); 293 } else if (in1->in(1) == in2->in(2)) { 294 // Convert a*b-c*a into a*(b-c) 295 sub_in1 = in1->in(2); 296 sub_in2 = in2->in(1); 297 mul_in = in1->in(1); 298 } 299 300 if (mul_in != nullptr) { 301 Node* sub = phase->transform(new SubINode(sub_in1, sub_in2)); 302 return new MulINode(mul_in, sub); 303 } 304 } 305 306 // Convert "0-(A>>31)" into "(A>>>31)" 307 if ( op2 == Op_RShiftI ) { 308 Node *in21 = in2->in(1); 309 Node *in22 = in2->in(2); 310 const TypeInt *zero = phase->type(in1)->isa_int(); 311 const TypeInt *t21 = phase->type(in21)->isa_int(); 312 const TypeInt *t22 = phase->type(in22)->isa_int(); 313 if ( t21 && t22 && zero == TypeInt::ZERO && t22->is_con(31) ) { 314 return new URShiftINode(in21, in22); 315 } 316 } 317 318 return nullptr; 319 } 320 321 //------------------------------sub-------------------------------------------- 322 // A subtract node differences it's two inputs. 323 const Type *SubINode::sub( const Type *t1, const Type *t2 ) const { 324 const TypeInt *r0 = t1->is_int(); // Handy access 325 const TypeInt *r1 = t2->is_int(); 326 int32_t lo = java_subtract(r0->_lo, r1->_hi); 327 int32_t hi = java_subtract(r0->_hi, r1->_lo); 328 329 // We next check for 32-bit overflow. 330 // If that happens, we just assume all integers are possible. 331 if( (((r0->_lo ^ r1->_hi) >= 0) || // lo ends have same signs OR 332 ((r0->_lo ^ lo) >= 0)) && // lo results have same signs AND 333 (((r0->_hi ^ r1->_lo) >= 0) || // hi ends have same signs OR 334 ((r0->_hi ^ hi) >= 0)) ) // hi results have same signs 335 return TypeInt::make(lo,hi,MAX2(r0->_widen,r1->_widen)); 336 else // Overflow; assume all integers 337 return TypeInt::INT; 338 } 339 340 //============================================================================= 341 //------------------------------Ideal------------------------------------------ 342 Node *SubLNode::Ideal(PhaseGVN *phase, bool can_reshape) { 343 Node *in1 = in(1); 344 Node *in2 = in(2); 345 uint op1 = in1->Opcode(); 346 uint op2 = in2->Opcode(); 347 348 #ifdef ASSERT 349 // Check for dead loop 350 if ((in1 == this) || (in2 == this) || 351 ((op1 == Op_AddL || op1 == Op_SubL) && 352 ((in1->in(1) == this) || (in1->in(2) == this) || 353 (in1->in(1) == in1) || (in1->in(2) == in1)))) { 354 assert(false, "dead loop in SubLNode::Ideal"); 355 } 356 #endif 357 358 if( phase->type( in2 ) == Type::TOP ) return nullptr; 359 const TypeLong *i = phase->type( in2 )->isa_long(); 360 // Convert "x-c0" into "x+ -c0". 361 if( i && // Might be bottom or top... 362 i->is_con() ) 363 return new AddLNode(in1, phase->longcon(java_negate(i->get_con()))); 364 365 // Convert "(x+c0) - y" into (x-y) + c0" 366 // Do not collapse (x+c0)-y if "+" is a loop increment or 367 // if "y" is a loop induction variable. 368 if( op1 == Op_AddL && ok_to_convert(in1, in2) ) { 369 Node *in11 = in1->in(1); 370 const Type *tadd = phase->type( in1->in(2) ); 371 if( tadd->singleton() && tadd != Type::TOP ) { 372 Node *sub2 = phase->transform( new SubLNode( in11, in2 )); 373 return new AddLNode( sub2, in1->in(2) ); 374 } 375 } 376 377 // Convert "x - (y+c0)" into "(x-y) - c0" AND 378 // Convert "c1 - (y+c0)" into "(c1-c0) - y" 379 // Need the same check as in above optimization but reversed. 380 if (op2 == Op_AddL 381 && ok_to_convert(in2, in1) 382 && in2->in(2)->Opcode() == Op_ConL) { 383 jlong c0 = phase->type(in2->in(2))->isa_long()->get_con(); 384 Node* in21 = in2->in(1); 385 if (in1->Opcode() == Op_ConL) { 386 // Match c1 387 jlong c1 = phase->type(in1)->isa_long()->get_con(); 388 Node* sub2 = phase->longcon(java_subtract(c1, c0)); 389 return new SubLNode(sub2, in21); 390 } else { 391 Node* sub2 = phase->transform(new SubLNode(in1, in21)); 392 Node* neg_c0 = phase->longcon(-c0); 393 return new AddLNode(sub2, neg_c0); 394 } 395 } 396 397 const Type *t1 = phase->type( in1 ); 398 if( t1 == Type::TOP ) return nullptr; 399 400 #ifdef ASSERT 401 // Check for dead loop 402 if ((op2 == Op_AddL || op2 == Op_SubL) && 403 ((in2->in(1) == this) || (in2->in(2) == this) || 404 (in2->in(1) == in2) || (in2->in(2) == in2))) { 405 assert(false, "dead loop in SubLNode::Ideal"); 406 } 407 #endif 408 409 // Convert "x - (x+y)" into "-y" 410 if (op2 == Op_AddL && in1 == in2->in(1)) { 411 return new SubLNode(phase->makecon(TypeLong::ZERO), in2->in(2)); 412 } 413 // Convert "(x-y) - x" into "-y" 414 if (op1 == Op_SubL && in1->in(1) == in2) { 415 return new SubLNode(phase->makecon(TypeLong::ZERO), in1->in(2)); 416 } 417 // Convert "x - (y+x)" into "-y" 418 if (op2 == Op_AddL && in1 == in2->in(2)) { 419 return new SubLNode(phase->makecon(TypeLong::ZERO), in2->in(1)); 420 } 421 422 // Convert "0 - (x-y)" into "y-x", leave the double negation "-(-y)" to SubNode::Identity. 423 if (t1 == TypeLong::ZERO && op2 == Op_SubL && phase->type(in2->in(1)) != TypeLong::ZERO) { 424 return new SubLNode(in2->in(2), in2->in(1)); 425 } 426 427 // Convert "(X+A) - (X+B)" into "A - B" 428 if( op1 == Op_AddL && op2 == Op_AddL && in1->in(1) == in2->in(1) ) 429 return new SubLNode( in1->in(2), in2->in(2) ); 430 431 // Convert "(A+X) - (B+X)" into "A - B" 432 if( op1 == Op_AddL && op2 == Op_AddL && in1->in(2) == in2->in(2) ) 433 return new SubLNode( in1->in(1), in2->in(1) ); 434 435 // Convert "(A+X) - (X+B)" into "A - B" 436 if( op1 == Op_AddL && op2 == Op_AddL && in1->in(2) == in2->in(1) ) 437 return new SubLNode( in1->in(1), in2->in(2) ); 438 439 // Convert "(X+A) - (B+X)" into "A - B" 440 if( op1 == Op_AddL && op2 == Op_AddL && in1->in(1) == in2->in(2) ) 441 return new SubLNode( in1->in(2), in2->in(1) ); 442 443 // Convert "A-(B-C)" into (A+C)-B" 444 if( op2 == Op_SubL && in2->outcnt() == 1) { 445 Node *add1 = phase->transform( new AddLNode( in1, in2->in(2) ) ); 446 return new SubLNode( add1, in2->in(1) ); 447 } 448 449 // Associative 450 if (op1 == Op_MulL && op2 == Op_MulL) { 451 Node* sub_in1 = nullptr; 452 Node* sub_in2 = nullptr; 453 Node* mul_in = nullptr; 454 455 if (in1->in(1) == in2->in(1)) { 456 // Convert "a*b-a*c into a*(b+c) 457 sub_in1 = in1->in(2); 458 sub_in2 = in2->in(2); 459 mul_in = in1->in(1); 460 } else if (in1->in(2) == in2->in(1)) { 461 // Convert a*b-b*c into b*(a-c) 462 sub_in1 = in1->in(1); 463 sub_in2 = in2->in(2); 464 mul_in = in1->in(2); 465 } else if (in1->in(2) == in2->in(2)) { 466 // Convert a*c-b*c into (a-b)*c 467 sub_in1 = in1->in(1); 468 sub_in2 = in2->in(1); 469 mul_in = in1->in(2); 470 } else if (in1->in(1) == in2->in(2)) { 471 // Convert a*b-c*a into a*(b-c) 472 sub_in1 = in1->in(2); 473 sub_in2 = in2->in(1); 474 mul_in = in1->in(1); 475 } 476 477 if (mul_in != nullptr) { 478 Node* sub = phase->transform(new SubLNode(sub_in1, sub_in2)); 479 return new MulLNode(mul_in, sub); 480 } 481 } 482 483 // Convert "0L-(A>>63)" into "(A>>>63)" 484 if ( op2 == Op_RShiftL ) { 485 Node *in21 = in2->in(1); 486 Node *in22 = in2->in(2); 487 const TypeLong *zero = phase->type(in1)->isa_long(); 488 const TypeLong *t21 = phase->type(in21)->isa_long(); 489 const TypeInt *t22 = phase->type(in22)->isa_int(); 490 if ( t21 && t22 && zero == TypeLong::ZERO && t22->is_con(63) ) { 491 return new URShiftLNode(in21, in22); 492 } 493 } 494 495 return nullptr; 496 } 497 498 //------------------------------sub-------------------------------------------- 499 // A subtract node differences it's two inputs. 500 const Type *SubLNode::sub( const Type *t1, const Type *t2 ) const { 501 const TypeLong *r0 = t1->is_long(); // Handy access 502 const TypeLong *r1 = t2->is_long(); 503 jlong lo = java_subtract(r0->_lo, r1->_hi); 504 jlong hi = java_subtract(r0->_hi, r1->_lo); 505 506 // We next check for 32-bit overflow. 507 // If that happens, we just assume all integers are possible. 508 if( (((r0->_lo ^ r1->_hi) >= 0) || // lo ends have same signs OR 509 ((r0->_lo ^ lo) >= 0)) && // lo results have same signs AND 510 (((r0->_hi ^ r1->_lo) >= 0) || // hi ends have same signs OR 511 ((r0->_hi ^ hi) >= 0)) ) // hi results have same signs 512 return TypeLong::make(lo,hi,MAX2(r0->_widen,r1->_widen)); 513 else // Overflow; assume all integers 514 return TypeLong::LONG; 515 } 516 517 //============================================================================= 518 //------------------------------Value------------------------------------------ 519 // A subtract node differences its two inputs. 520 const Type* SubFPNode::Value(PhaseGVN* phase) const { 521 const Node* in1 = in(1); 522 const Node* in2 = in(2); 523 // Either input is TOP ==> the result is TOP 524 const Type* t1 = (in1 == this) ? Type::TOP : phase->type(in1); 525 if( t1 == Type::TOP ) return Type::TOP; 526 const Type* t2 = (in2 == this) ? Type::TOP : phase->type(in2); 527 if( t2 == Type::TOP ) return Type::TOP; 528 529 // if both operands are infinity of same sign, the result is NaN; do 530 // not replace with zero 531 if (t1->is_finite() && t2->is_finite() && in1 == in2) { 532 return add_id(); 533 } 534 535 // Either input is BOTTOM ==> the result is the local BOTTOM 536 const Type *bot = bottom_type(); 537 if( (t1 == bot) || (t2 == bot) || 538 (t1 == Type::BOTTOM) || (t2 == Type::BOTTOM) ) 539 return bot; 540 541 return sub(t1,t2); // Local flavor of type subtraction 542 } 543 544 545 //============================================================================= 546 //------------------------------Ideal------------------------------------------ 547 Node *SubFNode::Ideal(PhaseGVN *phase, bool can_reshape) { 548 const Type *t2 = phase->type( in(2) ); 549 // Convert "x-c0" into "x+ -c0". 550 if( t2->base() == Type::FloatCon ) { // Might be bottom or top... 551 // return new (phase->C, 3) AddFNode(in(1), phase->makecon( TypeF::make(-t2->getf()) ) ); 552 } 553 554 // Cannot replace 0.0-X with -X because a 'fsub' bytecode computes 555 // 0.0-0.0 as +0.0, while a 'fneg' bytecode computes -0.0. 556 //if( phase->type(in(1)) == TypeF::ZERO ) 557 //return new (phase->C, 2) NegFNode(in(2)); 558 559 return nullptr; 560 } 561 562 //------------------------------sub-------------------------------------------- 563 // A subtract node differences its two inputs. 564 const Type *SubFNode::sub( const Type *t1, const Type *t2 ) const { 565 // no folding if one of operands is infinity or NaN, do not do constant folding 566 if( g_isfinite(t1->getf()) && g_isfinite(t2->getf()) ) { 567 return TypeF::make( t1->getf() - t2->getf() ); 568 } 569 else if( g_isnan(t1->getf()) ) { 570 return t1; 571 } 572 else if( g_isnan(t2->getf()) ) { 573 return t2; 574 } 575 else { 576 return Type::FLOAT; 577 } 578 } 579 580 //============================================================================= 581 //------------------------------Ideal------------------------------------------ 582 Node *SubDNode::Ideal(PhaseGVN *phase, bool can_reshape){ 583 const Type *t2 = phase->type( in(2) ); 584 // Convert "x-c0" into "x+ -c0". 585 if( t2->base() == Type::DoubleCon ) { // Might be bottom or top... 586 // return new (phase->C, 3) AddDNode(in(1), phase->makecon( TypeD::make(-t2->getd()) ) ); 587 } 588 589 // Cannot replace 0.0-X with -X because a 'dsub' bytecode computes 590 // 0.0-0.0 as +0.0, while a 'dneg' bytecode computes -0.0. 591 //if( phase->type(in(1)) == TypeD::ZERO ) 592 //return new (phase->C, 2) NegDNode(in(2)); 593 594 return nullptr; 595 } 596 597 //------------------------------sub-------------------------------------------- 598 // A subtract node differences its two inputs. 599 const Type *SubDNode::sub( const Type *t1, const Type *t2 ) const { 600 // no folding if one of operands is infinity or NaN, do not do constant folding 601 if( g_isfinite(t1->getd()) && g_isfinite(t2->getd()) ) { 602 return TypeD::make( t1->getd() - t2->getd() ); 603 } 604 else if( g_isnan(t1->getd()) ) { 605 return t1; 606 } 607 else if( g_isnan(t2->getd()) ) { 608 return t2; 609 } 610 else { 611 return Type::DOUBLE; 612 } 613 } 614 615 //============================================================================= 616 //------------------------------Idealize--------------------------------------- 617 // Unlike SubNodes, compare must still flatten return value to the 618 // range -1, 0, 1. 619 // And optimizations like those for (X + Y) - X fail if overflow happens. 620 Node* CmpNode::Identity(PhaseGVN* phase) { 621 return this; 622 } 623 624 CmpNode *CmpNode::make(Node *in1, Node *in2, BasicType bt, bool unsigned_comp) { 625 switch (bt) { 626 case T_INT: 627 if (unsigned_comp) { 628 return new CmpUNode(in1, in2); 629 } 630 return new CmpINode(in1, in2); 631 case T_LONG: 632 if (unsigned_comp) { 633 return new CmpULNode(in1, in2); 634 } 635 return new CmpLNode(in1, in2); 636 default: 637 fatal("Not implemented for %s", type2name(bt)); 638 } 639 return nullptr; 640 } 641 642 //============================================================================= 643 //------------------------------cmp-------------------------------------------- 644 // Simplify a CmpI (compare 2 integers) node, based on local information. 645 // If both inputs are constants, compare them. 646 const Type *CmpINode::sub( const Type *t1, const Type *t2 ) const { 647 const TypeInt *r0 = t1->is_int(); // Handy access 648 const TypeInt *r1 = t2->is_int(); 649 650 if( r0->_hi < r1->_lo ) // Range is always low? 651 return TypeInt::CC_LT; 652 else if( r0->_lo > r1->_hi ) // Range is always high? 653 return TypeInt::CC_GT; 654 655 else if( r0->is_con() && r1->is_con() ) { // comparing constants? 656 assert(r0->get_con() == r1->get_con(), "must be equal"); 657 return TypeInt::CC_EQ; // Equal results. 658 } else if( r0->_hi == r1->_lo ) // Range is never high? 659 return TypeInt::CC_LE; 660 else if( r0->_lo == r1->_hi ) // Range is never low? 661 return TypeInt::CC_GE; 662 return TypeInt::CC; // else use worst case results 663 } 664 665 const Type* CmpINode::Value(PhaseGVN* phase) const { 666 Node* in1 = in(1); 667 Node* in2 = in(2); 668 // If this test is the zero trip guard for a main or post loop, check whether, with the opaque node removed, the test 669 // would constant fold so the loop is never entered. If so return the type of the test without the opaque node removed: 670 // make the loop unreachable. 671 // The reason for this is that the iv phi captures the bounds of the loop and if the loop becomes unreachable, it can 672 // become top. In that case, the loop must be removed. 673 // This is safe because: 674 // - as optimizations proceed, the range of iterations executed by the main loop narrows. If no iterations remain, then 675 // we're done with optimizations for that loop. 676 // - the post loop is initially not reachable but as long as there's a main loop, the zero trip guard for the post 677 // loop takes a phi that merges the pre and main loop's iv and can't constant fold the zero trip guard. Once, the main 678 // loop is removed, there's no need to preserve the zero trip guard for the post loop anymore. 679 if (in1 != nullptr && in2 != nullptr) { 680 uint input = 0; 681 Node* cmp = nullptr; 682 BoolTest::mask test; 683 if (in1->Opcode() == Op_OpaqueZeroTripGuard && phase->type(in1) != Type::TOP) { 684 cmp = new CmpINode(in1->in(1), in2); 685 test = ((OpaqueZeroTripGuardNode*)in1)->_loop_entered_mask; 686 } 687 if (in2->Opcode() == Op_OpaqueZeroTripGuard && phase->type(in2) != Type::TOP) { 688 assert(cmp == nullptr, "A cmp with 2 OpaqueZeroTripGuard inputs"); 689 cmp = new CmpINode(in1, in2->in(1)); 690 test = ((OpaqueZeroTripGuardNode*)in2)->_loop_entered_mask; 691 } 692 if (cmp != nullptr) { 693 const Type* cmp_t = cmp->Value(phase); 694 const Type* t = BoolTest(test).cc2logical(cmp_t); 695 cmp->destruct(phase); 696 if (t == TypeInt::ZERO) { 697 return cmp_t; 698 } 699 } 700 } 701 702 return SubNode::Value(phase); 703 } 704 705 706 // Simplify a CmpU (compare 2 integers) node, based on local information. 707 // If both inputs are constants, compare them. 708 const Type *CmpUNode::sub( const Type *t1, const Type *t2 ) const { 709 assert(!t1->isa_ptr(), "obsolete usage of CmpU"); 710 711 // comparing two unsigned ints 712 const TypeInt *r0 = t1->is_int(); // Handy access 713 const TypeInt *r1 = t2->is_int(); 714 715 // Current installed version 716 // Compare ranges for non-overlap 717 juint lo0 = r0->_lo; 718 juint hi0 = r0->_hi; 719 juint lo1 = r1->_lo; 720 juint hi1 = r1->_hi; 721 722 // If either one has both negative and positive values, 723 // it therefore contains both 0 and -1, and since [0..-1] is the 724 // full unsigned range, the type must act as an unsigned bottom. 725 bool bot0 = ((jint)(lo0 ^ hi0) < 0); 726 bool bot1 = ((jint)(lo1 ^ hi1) < 0); 727 728 if (bot0 || bot1) { 729 // All unsigned values are LE -1 and GE 0. 730 if (lo0 == 0 && hi0 == 0) { 731 return TypeInt::CC_LE; // 0 <= bot 732 } else if ((jint)lo0 == -1 && (jint)hi0 == -1) { 733 return TypeInt::CC_GE; // -1 >= bot 734 } else if (lo1 == 0 && hi1 == 0) { 735 return TypeInt::CC_GE; // bot >= 0 736 } else if ((jint)lo1 == -1 && (jint)hi1 == -1) { 737 return TypeInt::CC_LE; // bot <= -1 738 } 739 } else { 740 // We can use ranges of the form [lo..hi] if signs are the same. 741 assert(lo0 <= hi0 && lo1 <= hi1, "unsigned ranges are valid"); 742 // results are reversed, '-' > '+' for unsigned compare 743 if (hi0 < lo1) { 744 return TypeInt::CC_LT; // smaller 745 } else if (lo0 > hi1) { 746 return TypeInt::CC_GT; // greater 747 } else if (hi0 == lo1 && lo0 == hi1) { 748 return TypeInt::CC_EQ; // Equal results 749 } else if (lo0 >= hi1) { 750 return TypeInt::CC_GE; 751 } else if (hi0 <= lo1) { 752 // Check for special case in Hashtable::get. (See below.) 753 if ((jint)lo0 >= 0 && (jint)lo1 >= 0 && is_index_range_check()) 754 return TypeInt::CC_LT; 755 return TypeInt::CC_LE; 756 } 757 } 758 // Check for special case in Hashtable::get - the hash index is 759 // mod'ed to the table size so the following range check is useless. 760 // Check for: (X Mod Y) CmpU Y, where the mod result and Y both have 761 // to be positive. 762 // (This is a gross hack, since the sub method never 763 // looks at the structure of the node in any other case.) 764 if ((jint)lo0 >= 0 && (jint)lo1 >= 0 && is_index_range_check()) 765 return TypeInt::CC_LT; 766 return TypeInt::CC; // else use worst case results 767 } 768 769 const Type* CmpUNode::Value(PhaseGVN* phase) const { 770 const Type* t = SubNode::Value_common(phase); 771 if (t != nullptr) { 772 return t; 773 } 774 const Node* in1 = in(1); 775 const Node* in2 = in(2); 776 const Type* t1 = phase->type(in1); 777 const Type* t2 = phase->type(in2); 778 assert(t1->isa_int(), "CmpU has only Int type inputs"); 779 if (t2 == TypeInt::INT) { // Compare to bottom? 780 return bottom_type(); 781 } 782 783 const Type* t_sub = sub(t1, t2); // compare based on immediate inputs 784 785 uint in1_op = in1->Opcode(); 786 if (in1_op == Op_AddI || in1_op == Op_SubI) { 787 // The problem rise when result of AddI(SubI) may overflow 788 // signed integer value. Let say the input type is 789 // [256, maxint] then +128 will create 2 ranges due to 790 // overflow: [minint, minint+127] and [384, maxint]. 791 // But C2 type system keep only 1 type range and as result 792 // it use general [minint, maxint] for this case which we 793 // can't optimize. 794 // 795 // Make 2 separate type ranges based on types of AddI(SubI) inputs 796 // and compare results of their compare. If results are the same 797 // CmpU node can be optimized. 798 const Node* in11 = in1->in(1); 799 const Node* in12 = in1->in(2); 800 const Type* t11 = (in11 == in1) ? Type::TOP : phase->type(in11); 801 const Type* t12 = (in12 == in1) ? Type::TOP : phase->type(in12); 802 // Skip cases when input types are top or bottom. 803 if ((t11 != Type::TOP) && (t11 != TypeInt::INT) && 804 (t12 != Type::TOP) && (t12 != TypeInt::INT)) { 805 const TypeInt *r0 = t11->is_int(); 806 const TypeInt *r1 = t12->is_int(); 807 jlong lo_r0 = r0->_lo; 808 jlong hi_r0 = r0->_hi; 809 jlong lo_r1 = r1->_lo; 810 jlong hi_r1 = r1->_hi; 811 if (in1_op == Op_SubI) { 812 jlong tmp = hi_r1; 813 hi_r1 = -lo_r1; 814 lo_r1 = -tmp; 815 // Note, for substructing [minint,x] type range 816 // long arithmetic provides correct overflow answer. 817 // The confusion come from the fact that in 32-bit 818 // -minint == minint but in 64-bit -minint == maxint+1. 819 } 820 jlong lo_long = lo_r0 + lo_r1; 821 jlong hi_long = hi_r0 + hi_r1; 822 int lo_tr1 = min_jint; 823 int hi_tr1 = (int)hi_long; 824 int lo_tr2 = (int)lo_long; 825 int hi_tr2 = max_jint; 826 bool underflow = lo_long != (jlong)lo_tr2; 827 bool overflow = hi_long != (jlong)hi_tr1; 828 // Use sub(t1, t2) when there is no overflow (one type range) 829 // or when both overflow and underflow (too complex). 830 if ((underflow != overflow) && (hi_tr1 < lo_tr2)) { 831 // Overflow only on one boundary, compare 2 separate type ranges. 832 int w = MAX2(r0->_widen, r1->_widen); // _widen does not matter here 833 const TypeInt* tr1 = TypeInt::make(lo_tr1, hi_tr1, w); 834 const TypeInt* tr2 = TypeInt::make(lo_tr2, hi_tr2, w); 835 const TypeInt* cmp1 = sub(tr1, t2)->is_int(); 836 const TypeInt* cmp2 = sub(tr2, t2)->is_int(); 837 // Compute union, so that cmp handles all possible results from the two cases 838 const Type* t_cmp = cmp1->meet(cmp2); 839 // Pick narrowest type, based on overflow computation and on immediate inputs 840 return t_sub->filter(t_cmp); 841 } 842 } 843 } 844 845 return t_sub; 846 } 847 848 bool CmpUNode::is_index_range_check() const { 849 // Check for the "(X ModI Y) CmpU Y" shape 850 return (in(1)->Opcode() == Op_ModI && 851 in(1)->in(2)->eqv_uncast(in(2))); 852 } 853 854 //------------------------------Idealize--------------------------------------- 855 Node *CmpINode::Ideal( PhaseGVN *phase, bool can_reshape ) { 856 if (phase->type(in(2))->higher_equal(TypeInt::ZERO)) { 857 switch (in(1)->Opcode()) { 858 case Op_CmpU3: // Collapse a CmpU3/CmpI into a CmpU 859 return new CmpUNode(in(1)->in(1),in(1)->in(2)); 860 case Op_CmpL3: // Collapse a CmpL3/CmpI into a CmpL 861 return new CmpLNode(in(1)->in(1),in(1)->in(2)); 862 case Op_CmpUL3: // Collapse a CmpUL3/CmpI into a CmpUL 863 return new CmpULNode(in(1)->in(1),in(1)->in(2)); 864 case Op_CmpF3: // Collapse a CmpF3/CmpI into a CmpF 865 return new CmpFNode(in(1)->in(1),in(1)->in(2)); 866 case Op_CmpD3: // Collapse a CmpD3/CmpI into a CmpD 867 return new CmpDNode(in(1)->in(1),in(1)->in(2)); 868 //case Op_SubI: 869 // If (x - y) cannot overflow, then ((x - y) <?> 0) 870 // can be turned into (x <?> y). 871 // This is handled (with more general cases) by Ideal_sub_algebra. 872 } 873 } 874 return nullptr; // No change 875 } 876 877 Node *CmpLNode::Ideal( PhaseGVN *phase, bool can_reshape ) { 878 const TypeLong *t2 = phase->type(in(2))->isa_long(); 879 if (Opcode() == Op_CmpL && in(1)->Opcode() == Op_ConvI2L && t2 && t2->is_con()) { 880 const jlong con = t2->get_con(); 881 if (con >= min_jint && con <= max_jint) { 882 return new CmpINode(in(1)->in(1), phase->intcon((jint)con)); 883 } 884 } 885 return nullptr; 886 } 887 888 //============================================================================= 889 // Simplify a CmpL (compare 2 longs ) node, based on local information. 890 // If both inputs are constants, compare them. 891 const Type *CmpLNode::sub( const Type *t1, const Type *t2 ) const { 892 const TypeLong *r0 = t1->is_long(); // Handy access 893 const TypeLong *r1 = t2->is_long(); 894 895 if( r0->_hi < r1->_lo ) // Range is always low? 896 return TypeInt::CC_LT; 897 else if( r0->_lo > r1->_hi ) // Range is always high? 898 return TypeInt::CC_GT; 899 900 else if( r0->is_con() && r1->is_con() ) { // comparing constants? 901 assert(r0->get_con() == r1->get_con(), "must be equal"); 902 return TypeInt::CC_EQ; // Equal results. 903 } else if( r0->_hi == r1->_lo ) // Range is never high? 904 return TypeInt::CC_LE; 905 else if( r0->_lo == r1->_hi ) // Range is never low? 906 return TypeInt::CC_GE; 907 return TypeInt::CC; // else use worst case results 908 } 909 910 911 // Simplify a CmpUL (compare 2 unsigned longs) node, based on local information. 912 // If both inputs are constants, compare them. 913 const Type* CmpULNode::sub(const Type* t1, const Type* t2) const { 914 assert(!t1->isa_ptr(), "obsolete usage of CmpUL"); 915 916 // comparing two unsigned longs 917 const TypeLong* r0 = t1->is_long(); // Handy access 918 const TypeLong* r1 = t2->is_long(); 919 920 // Current installed version 921 // Compare ranges for non-overlap 922 julong lo0 = r0->_lo; 923 julong hi0 = r0->_hi; 924 julong lo1 = r1->_lo; 925 julong hi1 = r1->_hi; 926 927 // If either one has both negative and positive values, 928 // it therefore contains both 0 and -1, and since [0..-1] is the 929 // full unsigned range, the type must act as an unsigned bottom. 930 bool bot0 = ((jlong)(lo0 ^ hi0) < 0); 931 bool bot1 = ((jlong)(lo1 ^ hi1) < 0); 932 933 if (bot0 || bot1) { 934 // All unsigned values are LE -1 and GE 0. 935 if (lo0 == 0 && hi0 == 0) { 936 return TypeInt::CC_LE; // 0 <= bot 937 } else if ((jlong)lo0 == -1 && (jlong)hi0 == -1) { 938 return TypeInt::CC_GE; // -1 >= bot 939 } else if (lo1 == 0 && hi1 == 0) { 940 return TypeInt::CC_GE; // bot >= 0 941 } else if ((jlong)lo1 == -1 && (jlong)hi1 == -1) { 942 return TypeInt::CC_LE; // bot <= -1 943 } 944 } else { 945 // We can use ranges of the form [lo..hi] if signs are the same. 946 assert(lo0 <= hi0 && lo1 <= hi1, "unsigned ranges are valid"); 947 // results are reversed, '-' > '+' for unsigned compare 948 if (hi0 < lo1) { 949 return TypeInt::CC_LT; // smaller 950 } else if (lo0 > hi1) { 951 return TypeInt::CC_GT; // greater 952 } else if (hi0 == lo1 && lo0 == hi1) { 953 return TypeInt::CC_EQ; // Equal results 954 } else if (lo0 >= hi1) { 955 return TypeInt::CC_GE; 956 } else if (hi0 <= lo1) { 957 return TypeInt::CC_LE; 958 } 959 } 960 961 return TypeInt::CC; // else use worst case results 962 } 963 964 //============================================================================= 965 //------------------------------sub-------------------------------------------- 966 // Simplify an CmpP (compare 2 pointers) node, based on local information. 967 // If both inputs are constants, compare them. 968 const Type *CmpPNode::sub( const Type *t1, const Type *t2 ) const { 969 const TypePtr *r0 = t1->is_ptr(); // Handy access 970 const TypePtr *r1 = t2->is_ptr(); 971 972 // Undefined inputs makes for an undefined result 973 if( TypePtr::above_centerline(r0->_ptr) || 974 TypePtr::above_centerline(r1->_ptr) ) 975 return Type::TOP; 976 977 if (r0 == r1 && r0->singleton()) { 978 // Equal pointer constants (klasses, nulls, etc.) 979 return TypeInt::CC_EQ; 980 } 981 982 // See if it is 2 unrelated classes. 983 const TypeOopPtr* p0 = r0->isa_oopptr(); 984 const TypeOopPtr* p1 = r1->isa_oopptr(); 985 const TypeKlassPtr* k0 = r0->isa_klassptr(); 986 const TypeKlassPtr* k1 = r1->isa_klassptr(); 987 if ((p0 && p1) || (k0 && k1)) { 988 if (p0 && p1) { 989 Node* in1 = in(1)->uncast(); 990 Node* in2 = in(2)->uncast(); 991 AllocateNode* alloc1 = AllocateNode::Ideal_allocation(in1); 992 AllocateNode* alloc2 = AllocateNode::Ideal_allocation(in2); 993 if (MemNode::detect_ptr_independence(in1, alloc1, in2, alloc2, nullptr)) { 994 return TypeInt::CC_GT; // different pointers 995 } 996 } 997 bool xklass0 = p0 ? p0->klass_is_exact() : k0->klass_is_exact(); 998 bool xklass1 = p1 ? p1->klass_is_exact() : k1->klass_is_exact(); 999 bool unrelated_classes = false; 1000 1001 if ((p0 && p0->is_same_java_type_as(p1)) || 1002 (k0 && k0->is_same_java_type_as(k1))) { 1003 } else if ((p0 && !p1->maybe_java_subtype_of(p0) && !p0->maybe_java_subtype_of(p1)) || 1004 (k0 && !k1->maybe_java_subtype_of(k0) && !k0->maybe_java_subtype_of(k1))) { 1005 unrelated_classes = true; 1006 } else if ((p0 && !p1->maybe_java_subtype_of(p0)) || 1007 (k0 && !k1->maybe_java_subtype_of(k0))) { 1008 unrelated_classes = xklass1; 1009 } else if ((p0 && !p0->maybe_java_subtype_of(p1)) || 1010 (k0 && !k0->maybe_java_subtype_of(k1))) { 1011 unrelated_classes = xklass0; 1012 } 1013 1014 if (unrelated_classes) { 1015 // The oops classes are known to be unrelated. If the joined PTRs of 1016 // two oops is not Null and not Bottom, then we are sure that one 1017 // of the two oops is non-null, and the comparison will always fail. 1018 TypePtr::PTR jp = r0->join_ptr(r1->_ptr); 1019 if (jp != TypePtr::Null && jp != TypePtr::BotPTR) { 1020 return TypeInt::CC_GT; 1021 } 1022 } 1023 } 1024 1025 // Known constants can be compared exactly 1026 // Null can be distinguished from any NotNull pointers 1027 // Unknown inputs makes an unknown result 1028 if( r0->singleton() ) { 1029 intptr_t bits0 = r0->get_con(); 1030 if( r1->singleton() ) 1031 return bits0 == r1->get_con() ? TypeInt::CC_EQ : TypeInt::CC_GT; 1032 return ( r1->_ptr == TypePtr::NotNull && bits0==0 ) ? TypeInt::CC_GT : TypeInt::CC; 1033 } else if( r1->singleton() ) { 1034 intptr_t bits1 = r1->get_con(); 1035 return ( r0->_ptr == TypePtr::NotNull && bits1==0 ) ? TypeInt::CC_GT : TypeInt::CC; 1036 } else 1037 return TypeInt::CC; 1038 } 1039 1040 static inline Node* isa_java_mirror_load(PhaseGVN* phase, Node* n) { 1041 // Return the klass node for (indirect load from OopHandle) 1042 // LoadBarrier?(LoadP(LoadP(AddP(foo:Klass, #java_mirror)))) 1043 // or null if not matching. 1044 BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2(); 1045 n = bs->step_over_gc_barrier(n); 1046 1047 if (n->Opcode() != Op_LoadP) return nullptr; 1048 1049 const TypeInstPtr* tp = phase->type(n)->isa_instptr(); 1050 if (!tp || tp->instance_klass() != phase->C->env()->Class_klass()) return nullptr; 1051 1052 Node* adr = n->in(MemNode::Address); 1053 // First load from OopHandle: ((OopHandle)mirror)->resolve(); may need barrier. 1054 if (adr->Opcode() != Op_LoadP || !phase->type(adr)->isa_rawptr()) return nullptr; 1055 adr = adr->in(MemNode::Address); 1056 1057 intptr_t off = 0; 1058 Node* k = AddPNode::Ideal_base_and_offset(adr, phase, off); 1059 if (k == nullptr) return nullptr; 1060 const TypeKlassPtr* tkp = phase->type(k)->isa_klassptr(); 1061 if (!tkp || off != in_bytes(Klass::java_mirror_offset())) return nullptr; 1062 1063 // We've found the klass node of a Java mirror load. 1064 return k; 1065 } 1066 1067 static inline Node* isa_const_java_mirror(PhaseGVN* phase, Node* n) { 1068 // for ConP(Foo.class) return ConP(Foo.klass) 1069 // otherwise return null 1070 if (!n->is_Con()) return nullptr; 1071 1072 const TypeInstPtr* tp = phase->type(n)->isa_instptr(); 1073 if (!tp) return nullptr; 1074 1075 ciType* mirror_type = tp->java_mirror_type(); 1076 // TypeInstPtr::java_mirror_type() returns non-null for compile- 1077 // time Class constants only. 1078 if (!mirror_type) return nullptr; 1079 1080 // x.getClass() == int.class can never be true (for all primitive types) 1081 // Return a ConP(null) node for this case. 1082 if (mirror_type->is_classless()) { 1083 return phase->makecon(TypePtr::NULL_PTR); 1084 } 1085 1086 // return the ConP(Foo.klass) 1087 assert(mirror_type->is_klass(), "mirror_type should represent a Klass*"); 1088 return phase->makecon(TypeKlassPtr::make(mirror_type->as_klass(), Type::trust_interfaces)); 1089 } 1090 1091 //------------------------------Ideal------------------------------------------ 1092 // Normalize comparisons between Java mirror loads to compare the klass instead. 1093 // 1094 // Also check for the case of comparing an unknown klass loaded from the primary 1095 // super-type array vs a known klass with no subtypes. This amounts to 1096 // checking to see an unknown klass subtypes a known klass with no subtypes; 1097 // this only happens on an exact match. We can shorten this test by 1 load. 1098 Node *CmpPNode::Ideal( PhaseGVN *phase, bool can_reshape ) { 1099 // Normalize comparisons between Java mirrors into comparisons of the low- 1100 // level klass, where a dependent load could be shortened. 1101 // 1102 // The new pattern has a nice effect of matching the same pattern used in the 1103 // fast path of instanceof/checkcast/Class.isInstance(), which allows 1104 // redundant exact type check be optimized away by GVN. 1105 // For example, in 1106 // if (x.getClass() == Foo.class) { 1107 // Foo foo = (Foo) x; 1108 // // ... use a ... 1109 // } 1110 // a CmpPNode could be shared between if_acmpne and checkcast 1111 { 1112 Node* k1 = isa_java_mirror_load(phase, in(1)); 1113 Node* k2 = isa_java_mirror_load(phase, in(2)); 1114 Node* conk2 = isa_const_java_mirror(phase, in(2)); 1115 1116 if (k1 && (k2 || conk2)) { 1117 Node* lhs = k1; 1118 Node* rhs = (k2 != nullptr) ? k2 : conk2; 1119 set_req_X(1, lhs, phase); 1120 set_req_X(2, rhs, phase); 1121 return this; 1122 } 1123 } 1124 1125 // Constant pointer on right? 1126 const TypeKlassPtr* t2 = phase->type(in(2))->isa_klassptr(); 1127 if (t2 == nullptr || !t2->klass_is_exact()) 1128 return nullptr; 1129 // Get the constant klass we are comparing to. 1130 ciKlass* superklass = t2->exact_klass(); 1131 1132 // Now check for LoadKlass on left. 1133 Node* ldk1 = in(1); 1134 if (ldk1->is_DecodeNKlass()) { 1135 ldk1 = ldk1->in(1); 1136 if (ldk1->Opcode() != Op_LoadNKlass ) 1137 return nullptr; 1138 } else if (ldk1->Opcode() != Op_LoadKlass ) 1139 return nullptr; 1140 // Take apart the address of the LoadKlass: 1141 Node* adr1 = ldk1->in(MemNode::Address); 1142 intptr_t con2 = 0; 1143 Node* ldk2 = AddPNode::Ideal_base_and_offset(adr1, phase, con2); 1144 if (ldk2 == nullptr) 1145 return nullptr; 1146 if (con2 == oopDesc::klass_offset_in_bytes()) { 1147 // We are inspecting an object's concrete class. 1148 // Short-circuit the check if the query is abstract. 1149 if (superklass->is_interface() || 1150 superklass->is_abstract()) { 1151 // Make it come out always false: 1152 this->set_req(2, phase->makecon(TypePtr::NULL_PTR)); 1153 return this; 1154 } 1155 } 1156 1157 // Check for a LoadKlass from primary supertype array. 1158 // Any nested loadklass from loadklass+con must be from the p.s. array. 1159 if (ldk2->is_DecodeNKlass()) { 1160 // Keep ldk2 as DecodeN since it could be used in CmpP below. 1161 if (ldk2->in(1)->Opcode() != Op_LoadNKlass ) 1162 return nullptr; 1163 } else if (ldk2->Opcode() != Op_LoadKlass) 1164 return nullptr; 1165 1166 // Verify that we understand the situation 1167 if (con2 != (intptr_t) superklass->super_check_offset()) 1168 return nullptr; // Might be element-klass loading from array klass 1169 1170 // If 'superklass' has no subklasses and is not an interface, then we are 1171 // assured that the only input which will pass the type check is 1172 // 'superklass' itself. 1173 // 1174 // We could be more liberal here, and allow the optimization on interfaces 1175 // which have a single implementor. This would require us to increase the 1176 // expressiveness of the add_dependency() mechanism. 1177 // %%% Do this after we fix TypeOopPtr: Deps are expressive enough now. 1178 1179 // Object arrays must have their base element have no subtypes 1180 while (superklass->is_obj_array_klass()) { 1181 ciType* elem = superklass->as_obj_array_klass()->element_type(); 1182 superklass = elem->as_klass(); 1183 } 1184 if (superklass->is_instance_klass()) { 1185 ciInstanceKlass* ik = superklass->as_instance_klass(); 1186 if (ik->has_subklass() || ik->is_interface()) return nullptr; 1187 // Add a dependency if there is a chance that a subclass will be added later. 1188 if (!ik->is_final()) { 1189 phase->C->dependencies()->assert_leaf_type(ik); 1190 } 1191 } 1192 1193 // Bypass the dependent load, and compare directly 1194 this->set_req_X(1, ldk2, phase); 1195 1196 return this; 1197 } 1198 1199 //============================================================================= 1200 //------------------------------sub-------------------------------------------- 1201 // Simplify an CmpN (compare 2 pointers) node, based on local information. 1202 // If both inputs are constants, compare them. 1203 const Type *CmpNNode::sub( const Type *t1, const Type *t2 ) const { 1204 ShouldNotReachHere(); 1205 return bottom_type(); 1206 } 1207 1208 //------------------------------Ideal------------------------------------------ 1209 Node *CmpNNode::Ideal( PhaseGVN *phase, bool can_reshape ) { 1210 return nullptr; 1211 } 1212 1213 //============================================================================= 1214 //------------------------------Value------------------------------------------ 1215 // Simplify an CmpF (compare 2 floats ) node, based on local information. 1216 // If both inputs are constants, compare them. 1217 const Type* CmpFNode::Value(PhaseGVN* phase) const { 1218 const Node* in1 = in(1); 1219 const Node* in2 = in(2); 1220 // Either input is TOP ==> the result is TOP 1221 const Type* t1 = (in1 == this) ? Type::TOP : phase->type(in1); 1222 if( t1 == Type::TOP ) return Type::TOP; 1223 const Type* t2 = (in2 == this) ? Type::TOP : phase->type(in2); 1224 if( t2 == Type::TOP ) return Type::TOP; 1225 1226 // Not constants? Don't know squat - even if they are the same 1227 // value! If they are NaN's they compare to LT instead of EQ. 1228 const TypeF *tf1 = t1->isa_float_constant(); 1229 const TypeF *tf2 = t2->isa_float_constant(); 1230 if( !tf1 || !tf2 ) return TypeInt::CC; 1231 1232 // This implements the Java bytecode fcmpl, so unordered returns -1. 1233 if( tf1->is_nan() || tf2->is_nan() ) 1234 return TypeInt::CC_LT; 1235 1236 if( tf1->_f < tf2->_f ) return TypeInt::CC_LT; 1237 if( tf1->_f > tf2->_f ) return TypeInt::CC_GT; 1238 assert( tf1->_f == tf2->_f, "do not understand FP behavior" ); 1239 return TypeInt::CC_EQ; 1240 } 1241 1242 1243 //============================================================================= 1244 //------------------------------Value------------------------------------------ 1245 // Simplify an CmpD (compare 2 doubles ) node, based on local information. 1246 // If both inputs are constants, compare them. 1247 const Type* CmpDNode::Value(PhaseGVN* phase) const { 1248 const Node* in1 = in(1); 1249 const Node* in2 = in(2); 1250 // Either input is TOP ==> the result is TOP 1251 const Type* t1 = (in1 == this) ? Type::TOP : phase->type(in1); 1252 if( t1 == Type::TOP ) return Type::TOP; 1253 const Type* t2 = (in2 == this) ? Type::TOP : phase->type(in2); 1254 if( t2 == Type::TOP ) return Type::TOP; 1255 1256 // Not constants? Don't know squat - even if they are the same 1257 // value! If they are NaN's they compare to LT instead of EQ. 1258 const TypeD *td1 = t1->isa_double_constant(); 1259 const TypeD *td2 = t2->isa_double_constant(); 1260 if( !td1 || !td2 ) return TypeInt::CC; 1261 1262 // This implements the Java bytecode dcmpl, so unordered returns -1. 1263 if( td1->is_nan() || td2->is_nan() ) 1264 return TypeInt::CC_LT; 1265 1266 if( td1->_d < td2->_d ) return TypeInt::CC_LT; 1267 if( td1->_d > td2->_d ) return TypeInt::CC_GT; 1268 assert( td1->_d == td2->_d, "do not understand FP behavior" ); 1269 return TypeInt::CC_EQ; 1270 } 1271 1272 //------------------------------Ideal------------------------------------------ 1273 Node *CmpDNode::Ideal(PhaseGVN *phase, bool can_reshape){ 1274 // Check if we can change this to a CmpF and remove a ConvD2F operation. 1275 // Change (CMPD (F2D (float)) (ConD value)) 1276 // To (CMPF (float) (ConF value)) 1277 // Valid when 'value' does not lose precision as a float. 1278 // Benefits: eliminates conversion, does not require 24-bit mode 1279 1280 // NaNs prevent commuting operands. This transform works regardless of the 1281 // order of ConD and ConvF2D inputs by preserving the original order. 1282 int idx_f2d = 1; // ConvF2D on left side? 1283 if( in(idx_f2d)->Opcode() != Op_ConvF2D ) 1284 idx_f2d = 2; // No, swap to check for reversed args 1285 int idx_con = 3-idx_f2d; // Check for the constant on other input 1286 1287 if( ConvertCmpD2CmpF && 1288 in(idx_f2d)->Opcode() == Op_ConvF2D && 1289 in(idx_con)->Opcode() == Op_ConD ) { 1290 const TypeD *t2 = in(idx_con)->bottom_type()->is_double_constant(); 1291 double t2_value_as_double = t2->_d; 1292 float t2_value_as_float = (float)t2_value_as_double; 1293 if( t2_value_as_double == (double)t2_value_as_float ) { 1294 // Test value can be represented as a float 1295 // Eliminate the conversion to double and create new comparison 1296 Node *new_in1 = in(idx_f2d)->in(1); 1297 Node *new_in2 = phase->makecon( TypeF::make(t2_value_as_float) ); 1298 if( idx_f2d != 1 ) { // Must flip args to match original order 1299 Node *tmp = new_in1; 1300 new_in1 = new_in2; 1301 new_in2 = tmp; 1302 } 1303 CmpFNode *new_cmp = (Opcode() == Op_CmpD3) 1304 ? new CmpF3Node( new_in1, new_in2 ) 1305 : new CmpFNode ( new_in1, new_in2 ) ; 1306 return new_cmp; // Changed to CmpFNode 1307 } 1308 // Testing value required the precision of a double 1309 } 1310 return nullptr; // No change 1311 } 1312 1313 1314 //============================================================================= 1315 //------------------------------cc2logical------------------------------------- 1316 // Convert a condition code type to a logical type 1317 const Type *BoolTest::cc2logical( const Type *CC ) const { 1318 if( CC == Type::TOP ) return Type::TOP; 1319 if( CC->base() != Type::Int ) return TypeInt::BOOL; // Bottom or worse 1320 const TypeInt *ti = CC->is_int(); 1321 if( ti->is_con() ) { // Only 1 kind of condition codes set? 1322 // Match low order 2 bits 1323 int tmp = ((ti->get_con()&3) == (_test&3)) ? 1 : 0; 1324 if( _test & 4 ) tmp = 1-tmp; // Optionally complement result 1325 return TypeInt::make(tmp); // Boolean result 1326 } 1327 1328 if( CC == TypeInt::CC_GE ) { 1329 if( _test == ge ) return TypeInt::ONE; 1330 if( _test == lt ) return TypeInt::ZERO; 1331 } 1332 if( CC == TypeInt::CC_LE ) { 1333 if( _test == le ) return TypeInt::ONE; 1334 if( _test == gt ) return TypeInt::ZERO; 1335 } 1336 1337 return TypeInt::BOOL; 1338 } 1339 1340 //------------------------------dump_spec------------------------------------- 1341 // Print special per-node info 1342 void BoolTest::dump_on(outputStream *st) const { 1343 const char *msg[] = {"eq","gt","of","lt","ne","le","nof","ge"}; 1344 st->print("%s", msg[_test]); 1345 } 1346 1347 // Returns the logical AND of two tests (or 'never' if both tests can never be true). 1348 // For example, a test for 'le' followed by a test for 'lt' is equivalent with 'lt'. 1349 BoolTest::mask BoolTest::merge(BoolTest other) const { 1350 const mask res[illegal+1][illegal+1] = { 1351 // eq, gt, of, lt, ne, le, nof, ge, never, illegal 1352 {eq, never, illegal, never, never, eq, illegal, eq, never, illegal}, // eq 1353 {never, gt, illegal, never, gt, never, illegal, gt, never, illegal}, // gt 1354 {illegal, illegal, illegal, illegal, illegal, illegal, illegal, illegal, never, illegal}, // of 1355 {never, never, illegal, lt, lt, lt, illegal, never, never, illegal}, // lt 1356 {never, gt, illegal, lt, ne, lt, illegal, gt, never, illegal}, // ne 1357 {eq, never, illegal, lt, lt, le, illegal, eq, never, illegal}, // le 1358 {illegal, illegal, illegal, illegal, illegal, illegal, illegal, illegal, never, illegal}, // nof 1359 {eq, gt, illegal, never, gt, eq, illegal, ge, never, illegal}, // ge 1360 {never, never, never, never, never, never, never, never, never, illegal}, // never 1361 {illegal, illegal, illegal, illegal, illegal, illegal, illegal, illegal, illegal, illegal}}; // illegal 1362 return res[_test][other._test]; 1363 } 1364 1365 //============================================================================= 1366 uint BoolNode::hash() const { return (Node::hash() << 3)|(_test._test+1); } 1367 uint BoolNode::size_of() const { return sizeof(BoolNode); } 1368 1369 //------------------------------operator==------------------------------------- 1370 bool BoolNode::cmp( const Node &n ) const { 1371 const BoolNode *b = (const BoolNode *)&n; // Cast up 1372 return (_test._test == b->_test._test); 1373 } 1374 1375 //-------------------------------make_predicate-------------------------------- 1376 Node* BoolNode::make_predicate(Node* test_value, PhaseGVN* phase) { 1377 if (test_value->is_Con()) return test_value; 1378 if (test_value->is_Bool()) return test_value; 1379 if (test_value->is_CMove() && 1380 test_value->in(CMoveNode::Condition)->is_Bool()) { 1381 BoolNode* bol = test_value->in(CMoveNode::Condition)->as_Bool(); 1382 const Type* ftype = phase->type(test_value->in(CMoveNode::IfFalse)); 1383 const Type* ttype = phase->type(test_value->in(CMoveNode::IfTrue)); 1384 if (ftype == TypeInt::ZERO && !TypeInt::ZERO->higher_equal(ttype)) { 1385 return bol; 1386 } else if (ttype == TypeInt::ZERO && !TypeInt::ZERO->higher_equal(ftype)) { 1387 return phase->transform( bol->negate(phase) ); 1388 } 1389 // Else fall through. The CMove gets in the way of the test. 1390 // It should be the case that make_predicate(bol->as_int_value()) == bol. 1391 } 1392 Node* cmp = new CmpINode(test_value, phase->intcon(0)); 1393 cmp = phase->transform(cmp); 1394 Node* bol = new BoolNode(cmp, BoolTest::ne); 1395 return phase->transform(bol); 1396 } 1397 1398 //--------------------------------as_int_value--------------------------------- 1399 Node* BoolNode::as_int_value(PhaseGVN* phase) { 1400 // Inverse to make_predicate. The CMove probably boils down to a Conv2B. 1401 Node* cmov = CMoveNode::make(nullptr, this, 1402 phase->intcon(0), phase->intcon(1), 1403 TypeInt::BOOL); 1404 return phase->transform(cmov); 1405 } 1406 1407 //----------------------------------negate------------------------------------- 1408 BoolNode* BoolNode::negate(PhaseGVN* phase) { 1409 return new BoolNode(in(1), _test.negate()); 1410 } 1411 1412 // Change "bool eq/ne (cmp (add/sub A B) C)" into false/true if add/sub 1413 // overflows and we can prove that C is not in the two resulting ranges. 1414 // This optimization is similar to the one performed by CmpUNode::Value(). 1415 Node* BoolNode::fold_cmpI(PhaseGVN* phase, SubNode* cmp, Node* cmp1, int cmp_op, 1416 int cmp1_op, const TypeInt* cmp2_type) { 1417 // Only optimize eq/ne integer comparison of add/sub 1418 if((_test._test == BoolTest::eq || _test._test == BoolTest::ne) && 1419 (cmp_op == Op_CmpI) && (cmp1_op == Op_AddI || cmp1_op == Op_SubI)) { 1420 // Skip cases were inputs of add/sub are not integers or of bottom type 1421 const TypeInt* r0 = phase->type(cmp1->in(1))->isa_int(); 1422 const TypeInt* r1 = phase->type(cmp1->in(2))->isa_int(); 1423 if ((r0 != nullptr) && (r0 != TypeInt::INT) && 1424 (r1 != nullptr) && (r1 != TypeInt::INT) && 1425 (cmp2_type != TypeInt::INT)) { 1426 // Compute exact (long) type range of add/sub result 1427 jlong lo_long = r0->_lo; 1428 jlong hi_long = r0->_hi; 1429 if (cmp1_op == Op_AddI) { 1430 lo_long += r1->_lo; 1431 hi_long += r1->_hi; 1432 } else { 1433 lo_long -= r1->_hi; 1434 hi_long -= r1->_lo; 1435 } 1436 // Check for over-/underflow by casting to integer 1437 int lo_int = (int)lo_long; 1438 int hi_int = (int)hi_long; 1439 bool underflow = lo_long != (jlong)lo_int; 1440 bool overflow = hi_long != (jlong)hi_int; 1441 if ((underflow != overflow) && (hi_int < lo_int)) { 1442 // Overflow on one boundary, compute resulting type ranges: 1443 // tr1 [MIN_INT, hi_int] and tr2 [lo_int, MAX_INT] 1444 int w = MAX2(r0->_widen, r1->_widen); // _widen does not matter here 1445 const TypeInt* tr1 = TypeInt::make(min_jint, hi_int, w); 1446 const TypeInt* tr2 = TypeInt::make(lo_int, max_jint, w); 1447 // Compare second input of cmp to both type ranges 1448 const Type* sub_tr1 = cmp->sub(tr1, cmp2_type); 1449 const Type* sub_tr2 = cmp->sub(tr2, cmp2_type); 1450 if (sub_tr1 == TypeInt::CC_LT && sub_tr2 == TypeInt::CC_GT) { 1451 // The result of the add/sub will never equal cmp2. Replace BoolNode 1452 // by false (0) if it tests for equality and by true (1) otherwise. 1453 return ConINode::make((_test._test == BoolTest::eq) ? 0 : 1); 1454 } 1455 } 1456 } 1457 } 1458 return nullptr; 1459 } 1460 1461 static bool is_counted_loop_cmp(Node *cmp) { 1462 Node *n = cmp->in(1)->in(1); 1463 return n != nullptr && 1464 n->is_Phi() && 1465 n->in(0) != nullptr && 1466 n->in(0)->is_CountedLoop() && 1467 n->in(0)->as_CountedLoop()->phi() == n; 1468 } 1469 1470 //------------------------------Ideal------------------------------------------ 1471 Node *BoolNode::Ideal(PhaseGVN *phase, bool can_reshape) { 1472 // Change "bool tst (cmp con x)" into "bool ~tst (cmp x con)". 1473 // This moves the constant to the right. Helps value-numbering. 1474 Node *cmp = in(1); 1475 if( !cmp->is_Sub() ) return nullptr; 1476 int cop = cmp->Opcode(); 1477 if( cop == Op_FastLock || cop == Op_FastUnlock || 1478 cmp->is_SubTypeCheck() || cop == Op_VectorTest ) { 1479 return nullptr; 1480 } 1481 Node *cmp1 = cmp->in(1); 1482 Node *cmp2 = cmp->in(2); 1483 if( !cmp1 ) return nullptr; 1484 1485 if (_test._test == BoolTest::overflow || _test._test == BoolTest::no_overflow) { 1486 return nullptr; 1487 } 1488 1489 const int cmp1_op = cmp1->Opcode(); 1490 const int cmp2_op = cmp2->Opcode(); 1491 1492 // Constant on left? 1493 Node *con = cmp1; 1494 // Move constants to the right of compare's to canonicalize. 1495 // Do not muck with Opaque1 nodes, as this indicates a loop 1496 // guard that cannot change shape. 1497 if (con->is_Con() && !cmp2->is_Con() && cmp2_op != Op_OpaqueZeroTripGuard && 1498 // Because of NaN's, CmpD and CmpF are not commutative 1499 cop != Op_CmpD && cop != Op_CmpF && 1500 // Protect against swapping inputs to a compare when it is used by a 1501 // counted loop exit, which requires maintaining the loop-limit as in(2) 1502 !is_counted_loop_exit_test() ) { 1503 // Ok, commute the constant to the right of the cmp node. 1504 // Clone the Node, getting a new Node of the same class 1505 cmp = cmp->clone(); 1506 // Swap inputs to the clone 1507 cmp->swap_edges(1, 2); 1508 cmp = phase->transform( cmp ); 1509 return new BoolNode( cmp, _test.commute() ); 1510 } 1511 1512 // Change "bool eq/ne (cmp (cmove (bool tst (cmp2)) 1 0) 0)" into "bool tst/~tst (cmp2)" 1513 if (cop == Op_CmpI && 1514 (_test._test == BoolTest::eq || _test._test == BoolTest::ne) && 1515 cmp1_op == Op_CMoveI && cmp2->find_int_con(1) == 0) { 1516 // 0 should be on the true branch 1517 if (cmp1->in(CMoveNode::Condition)->is_Bool() && 1518 cmp1->in(CMoveNode::IfTrue)->find_int_con(1) == 0 && 1519 cmp1->in(CMoveNode::IfFalse)->find_int_con(0) != 0) { 1520 BoolNode* target = cmp1->in(CMoveNode::Condition)->as_Bool(); 1521 return new BoolNode(target->in(1), 1522 (_test._test == BoolTest::eq) ? target->_test._test : 1523 target->_test.negate()); 1524 } 1525 } 1526 1527 // Change "bool eq/ne (cmp (and X 16) 16)" into "bool ne/eq (cmp (and X 16) 0)". 1528 if (cop == Op_CmpI && 1529 (_test._test == BoolTest::eq || _test._test == BoolTest::ne) && 1530 cmp1_op == Op_AndI && cmp2_op == Op_ConI && 1531 cmp1->in(2)->Opcode() == Op_ConI) { 1532 const TypeInt *t12 = phase->type(cmp2)->isa_int(); 1533 const TypeInt *t112 = phase->type(cmp1->in(2))->isa_int(); 1534 if (t12 && t12->is_con() && t112 && t112->is_con() && 1535 t12->get_con() == t112->get_con() && is_power_of_2(t12->get_con())) { 1536 Node *ncmp = phase->transform(new CmpINode(cmp1, phase->intcon(0))); 1537 return new BoolNode(ncmp, _test.negate()); 1538 } 1539 } 1540 1541 // Same for long type: change "bool eq/ne (cmp (and X 16) 16)" into "bool ne/eq (cmp (and X 16) 0)". 1542 if (cop == Op_CmpL && 1543 (_test._test == BoolTest::eq || _test._test == BoolTest::ne) && 1544 cmp1_op == Op_AndL && cmp2_op == Op_ConL && 1545 cmp1->in(2)->Opcode() == Op_ConL) { 1546 const TypeLong *t12 = phase->type(cmp2)->isa_long(); 1547 const TypeLong *t112 = phase->type(cmp1->in(2))->isa_long(); 1548 if (t12 && t12->is_con() && t112 && t112->is_con() && 1549 t12->get_con() == t112->get_con() && is_power_of_2(t12->get_con())) { 1550 Node *ncmp = phase->transform(new CmpLNode(cmp1, phase->longcon(0))); 1551 return new BoolNode(ncmp, _test.negate()); 1552 } 1553 } 1554 1555 // Change "cmp (add X min_jint) (add Y min_jint)" into "cmpu X Y" 1556 // and "cmp (add X min_jint) c" into "cmpu X (c + min_jint)" 1557 if (cop == Op_CmpI && 1558 cmp1_op == Op_AddI && 1559 !is_cloop_increment(cmp1) && 1560 phase->type(cmp1->in(2)) == TypeInt::MIN) { 1561 if (cmp2_op == Op_ConI) { 1562 Node* ncmp2 = phase->intcon(java_add(cmp2->get_int(), min_jint)); 1563 Node* ncmp = phase->transform(new CmpUNode(cmp1->in(1), ncmp2)); 1564 return new BoolNode(ncmp, _test._test); 1565 } else if (cmp2_op == Op_AddI && 1566 !is_cloop_increment(cmp2) && 1567 phase->type(cmp2->in(2)) == TypeInt::MIN) { 1568 Node* ncmp = phase->transform(new CmpUNode(cmp1->in(1), cmp2->in(1))); 1569 return new BoolNode(ncmp, _test._test); 1570 } 1571 } 1572 1573 // Change "cmp (add X min_jlong) (add Y min_jlong)" into "cmpu X Y" 1574 // and "cmp (add X min_jlong) c" into "cmpu X (c + min_jlong)" 1575 if (cop == Op_CmpL && 1576 cmp1_op == Op_AddL && 1577 !is_cloop_increment(cmp1) && 1578 phase->type(cmp1->in(2)) == TypeLong::MIN) { 1579 if (cmp2_op == Op_ConL) { 1580 Node* ncmp2 = phase->longcon(java_add(cmp2->get_long(), min_jlong)); 1581 Node* ncmp = phase->transform(new CmpULNode(cmp1->in(1), ncmp2)); 1582 return new BoolNode(ncmp, _test._test); 1583 } else if (cmp2_op == Op_AddL && 1584 !is_cloop_increment(cmp2) && 1585 phase->type(cmp2->in(2)) == TypeLong::MIN) { 1586 Node* ncmp = phase->transform(new CmpULNode(cmp1->in(1), cmp2->in(1))); 1587 return new BoolNode(ncmp, _test._test); 1588 } 1589 } 1590 1591 // Change "bool eq/ne (cmp (xor X 1) 0)" into "bool ne/eq (cmp X 0)". 1592 // The XOR-1 is an idiom used to flip the sense of a bool. We flip the 1593 // test instead. 1594 const TypeInt* cmp2_type = phase->type(cmp2)->isa_int(); 1595 if (cmp2_type == nullptr) return nullptr; 1596 Node* j_xor = cmp1; 1597 if( cmp2_type == TypeInt::ZERO && 1598 cmp1_op == Op_XorI && 1599 j_xor->in(1) != j_xor && // An xor of itself is dead 1600 phase->type( j_xor->in(1) ) == TypeInt::BOOL && 1601 phase->type( j_xor->in(2) ) == TypeInt::ONE && 1602 (_test._test == BoolTest::eq || 1603 _test._test == BoolTest::ne) ) { 1604 Node *ncmp = phase->transform(new CmpINode(j_xor->in(1),cmp2)); 1605 return new BoolNode( ncmp, _test.negate() ); 1606 } 1607 1608 // Change ((x & m) u<= m) or ((m & x) u<= m) to always true 1609 // Same with ((x & m) u< m+1) and ((m & x) u< m+1) 1610 if (cop == Op_CmpU && 1611 cmp1_op == Op_AndI) { 1612 Node* bound = nullptr; 1613 if (_test._test == BoolTest::le) { 1614 bound = cmp2; 1615 } else if (_test._test == BoolTest::lt && 1616 cmp2->Opcode() == Op_AddI && 1617 cmp2->in(2)->find_int_con(0) == 1) { 1618 bound = cmp2->in(1); 1619 } 1620 if (cmp1->in(2) == bound || cmp1->in(1) == bound) { 1621 return ConINode::make(1); 1622 } 1623 } 1624 1625 // Change ((x & (m - 1)) u< m) into (m > 0) 1626 // This is the off-by-one variant of the above 1627 if (cop == Op_CmpU && 1628 _test._test == BoolTest::lt && 1629 cmp1_op == Op_AndI) { 1630 Node* l = cmp1->in(1); 1631 Node* r = cmp1->in(2); 1632 for (int repeat = 0; repeat < 2; repeat++) { 1633 bool match = r->Opcode() == Op_AddI && r->in(2)->find_int_con(0) == -1 && 1634 r->in(1) == cmp2; 1635 if (match) { 1636 // arraylength known to be non-negative, so a (arraylength != 0) is sufficient, 1637 // but to be compatible with the array range check pattern, use (arraylength u> 0) 1638 Node* ncmp = cmp2->Opcode() == Op_LoadRange 1639 ? phase->transform(new CmpUNode(cmp2, phase->intcon(0))) 1640 : phase->transform(new CmpINode(cmp2, phase->intcon(0))); 1641 return new BoolNode(ncmp, BoolTest::gt); 1642 } else { 1643 // commute and try again 1644 l = cmp1->in(2); 1645 r = cmp1->in(1); 1646 } 1647 } 1648 } 1649 1650 // Change x u< 1 or x u<= 0 to x == 0 1651 // and x u> 0 or u>= 1 to x != 0 1652 if (cop == Op_CmpU && 1653 cmp1_op != Op_LoadRange && 1654 (((_test._test == BoolTest::lt || _test._test == BoolTest::ge) && 1655 cmp2->find_int_con(-1) == 1) || 1656 ((_test._test == BoolTest::le || _test._test == BoolTest::gt) && 1657 cmp2->find_int_con(-1) == 0))) { 1658 Node* ncmp = phase->transform(new CmpINode(cmp1, phase->intcon(0))); 1659 return new BoolNode(ncmp, _test.is_less() ? BoolTest::eq : BoolTest::ne); 1660 } 1661 1662 // Change (arraylength <= 0) or (arraylength == 0) 1663 // into (arraylength u<= 0) 1664 // Also change (arraylength != 0) into (arraylength u> 0) 1665 // The latter version matches the code pattern generated for 1666 // array range checks, which will more likely be optimized later. 1667 if (cop == Op_CmpI && 1668 cmp1_op == Op_LoadRange && 1669 cmp2->find_int_con(-1) == 0) { 1670 if (_test._test == BoolTest::le || _test._test == BoolTest::eq) { 1671 Node* ncmp = phase->transform(new CmpUNode(cmp1, cmp2)); 1672 return new BoolNode(ncmp, BoolTest::le); 1673 } else if (_test._test == BoolTest::ne) { 1674 Node* ncmp = phase->transform(new CmpUNode(cmp1, cmp2)); 1675 return new BoolNode(ncmp, BoolTest::gt); 1676 } 1677 } 1678 1679 // Change "bool eq/ne (cmp (Conv2B X) 0)" into "bool eq/ne (cmp X 0)". 1680 // This is a standard idiom for branching on a boolean value. 1681 Node *c2b = cmp1; 1682 if( cmp2_type == TypeInt::ZERO && 1683 cmp1_op == Op_Conv2B && 1684 (_test._test == BoolTest::eq || 1685 _test._test == BoolTest::ne) ) { 1686 Node *ncmp = phase->transform(phase->type(c2b->in(1))->isa_int() 1687 ? (Node*)new CmpINode(c2b->in(1),cmp2) 1688 : (Node*)new CmpPNode(c2b->in(1),phase->makecon(TypePtr::NULL_PTR)) 1689 ); 1690 return new BoolNode( ncmp, _test._test ); 1691 } 1692 1693 // Comparing a SubI against a zero is equal to comparing the SubI 1694 // arguments directly. This only works for eq and ne comparisons 1695 // due to possible integer overflow. 1696 if ((_test._test == BoolTest::eq || _test._test == BoolTest::ne) && 1697 (cop == Op_CmpI) && 1698 (cmp1_op == Op_SubI) && 1699 ( cmp2_type == TypeInt::ZERO ) ) { 1700 Node *ncmp = phase->transform( new CmpINode(cmp1->in(1),cmp1->in(2))); 1701 return new BoolNode( ncmp, _test._test ); 1702 } 1703 1704 // Same as above but with and AddI of a constant 1705 if ((_test._test == BoolTest::eq || _test._test == BoolTest::ne) && 1706 cop == Op_CmpI && 1707 cmp1_op == Op_AddI && 1708 cmp1->in(2) != nullptr && 1709 phase->type(cmp1->in(2))->isa_int() && 1710 phase->type(cmp1->in(2))->is_int()->is_con() && 1711 cmp2_type == TypeInt::ZERO && 1712 !is_counted_loop_cmp(cmp) // modifying the exit test of a counted loop messes the counted loop shape 1713 ) { 1714 const TypeInt* cmp1_in2 = phase->type(cmp1->in(2))->is_int(); 1715 Node *ncmp = phase->transform( new CmpINode(cmp1->in(1),phase->intcon(-cmp1_in2->_hi))); 1716 return new BoolNode( ncmp, _test._test ); 1717 } 1718 1719 // Change "bool eq/ne (cmp (phi (X -X) 0))" into "bool eq/ne (cmp X 0)" 1720 // since zero check of conditional negation of an integer is equal to 1721 // zero check of the integer directly. 1722 if ((_test._test == BoolTest::eq || _test._test == BoolTest::ne) && 1723 (cop == Op_CmpI) && 1724 (cmp2_type == TypeInt::ZERO) && 1725 (cmp1_op == Op_Phi)) { 1726 // There should be a diamond phi with true path at index 1 or 2 1727 PhiNode *phi = cmp1->as_Phi(); 1728 int idx_true = phi->is_diamond_phi(); 1729 if (idx_true != 0) { 1730 // True input is in(idx_true) while false input is in(3 - idx_true) 1731 Node *tin = phi->in(idx_true); 1732 Node *fin = phi->in(3 - idx_true); 1733 if ((tin->Opcode() == Op_SubI) && 1734 (phase->type(tin->in(1)) == TypeInt::ZERO) && 1735 (tin->in(2) == fin)) { 1736 // Found conditional negation at true path, create a new CmpINode without that 1737 Node *ncmp = phase->transform(new CmpINode(fin, cmp2)); 1738 return new BoolNode(ncmp, _test._test); 1739 } 1740 if ((fin->Opcode() == Op_SubI) && 1741 (phase->type(fin->in(1)) == TypeInt::ZERO) && 1742 (fin->in(2) == tin)) { 1743 // Found conditional negation at false path, create a new CmpINode without that 1744 Node *ncmp = phase->transform(new CmpINode(tin, cmp2)); 1745 return new BoolNode(ncmp, _test._test); 1746 } 1747 } 1748 } 1749 1750 // Change (-A vs 0) into (A vs 0) by commuting the test. Disallow in the 1751 // most general case because negating 0x80000000 does nothing. Needed for 1752 // the CmpF3/SubI/CmpI idiom. 1753 if( cop == Op_CmpI && 1754 cmp1_op == Op_SubI && 1755 cmp2_type == TypeInt::ZERO && 1756 phase->type( cmp1->in(1) ) == TypeInt::ZERO && 1757 phase->type( cmp1->in(2) )->higher_equal(TypeInt::SYMINT) ) { 1758 Node *ncmp = phase->transform( new CmpINode(cmp1->in(2),cmp2)); 1759 return new BoolNode( ncmp, _test.commute() ); 1760 } 1761 1762 // Try to optimize signed integer comparison 1763 return fold_cmpI(phase, cmp->as_Sub(), cmp1, cop, cmp1_op, cmp2_type); 1764 1765 // The transformation below is not valid for either signed or unsigned 1766 // comparisons due to wraparound concerns at MAX_VALUE and MIN_VALUE. 1767 // This transformation can be resurrected when we are able to 1768 // make inferences about the range of values being subtracted from 1769 // (or added to) relative to the wraparound point. 1770 // 1771 // // Remove +/-1's if possible. 1772 // // "X <= Y-1" becomes "X < Y" 1773 // // "X+1 <= Y" becomes "X < Y" 1774 // // "X < Y+1" becomes "X <= Y" 1775 // // "X-1 < Y" becomes "X <= Y" 1776 // // Do not this to compares off of the counted-loop-end. These guys are 1777 // // checking the trip counter and they want to use the post-incremented 1778 // // counter. If they use the PRE-incremented counter, then the counter has 1779 // // to be incremented in a private block on a loop backedge. 1780 // if( du && du->cnt(this) && du->out(this)[0]->Opcode() == Op_CountedLoopEnd ) 1781 // return nullptr; 1782 // #ifndef PRODUCT 1783 // // Do not do this in a wash GVN pass during verification. 1784 // // Gets triggered by too many simple optimizations to be bothered with 1785 // // re-trying it again and again. 1786 // if( !phase->allow_progress() ) return nullptr; 1787 // #endif 1788 // // Not valid for unsigned compare because of corner cases in involving zero. 1789 // // For example, replacing "X-1 <u Y" with "X <=u Y" fails to throw an 1790 // // exception in case X is 0 (because 0-1 turns into 4billion unsigned but 1791 // // "0 <=u Y" is always true). 1792 // if( cmp->Opcode() == Op_CmpU ) return nullptr; 1793 // int cmp2_op = cmp2->Opcode(); 1794 // if( _test._test == BoolTest::le ) { 1795 // if( cmp1_op == Op_AddI && 1796 // phase->type( cmp1->in(2) ) == TypeInt::ONE ) 1797 // return clone_cmp( cmp, cmp1->in(1), cmp2, phase, BoolTest::lt ); 1798 // else if( cmp2_op == Op_AddI && 1799 // phase->type( cmp2->in(2) ) == TypeInt::MINUS_1 ) 1800 // return clone_cmp( cmp, cmp1, cmp2->in(1), phase, BoolTest::lt ); 1801 // } else if( _test._test == BoolTest::lt ) { 1802 // if( cmp1_op == Op_AddI && 1803 // phase->type( cmp1->in(2) ) == TypeInt::MINUS_1 ) 1804 // return clone_cmp( cmp, cmp1->in(1), cmp2, phase, BoolTest::le ); 1805 // else if( cmp2_op == Op_AddI && 1806 // phase->type( cmp2->in(2) ) == TypeInt::ONE ) 1807 // return clone_cmp( cmp, cmp1, cmp2->in(1), phase, BoolTest::le ); 1808 // } 1809 } 1810 1811 //------------------------------Value------------------------------------------ 1812 // Simplify a Bool (convert condition codes to boolean (1 or 0)) node, 1813 // based on local information. If the input is constant, do it. 1814 const Type* BoolNode::Value(PhaseGVN* phase) const { 1815 return _test.cc2logical( phase->type( in(1) ) ); 1816 } 1817 1818 #ifndef PRODUCT 1819 //------------------------------dump_spec-------------------------------------- 1820 // Dump special per-node info 1821 void BoolNode::dump_spec(outputStream *st) const { 1822 st->print("["); 1823 _test.dump_on(st); 1824 st->print("]"); 1825 } 1826 #endif 1827 1828 //----------------------is_counted_loop_exit_test------------------------------ 1829 // Returns true if node is used by a counted loop node. 1830 bool BoolNode::is_counted_loop_exit_test() { 1831 for( DUIterator_Fast imax, i = fast_outs(imax); i < imax; i++ ) { 1832 Node* use = fast_out(i); 1833 if (use->is_CountedLoopEnd()) { 1834 return true; 1835 } 1836 } 1837 return false; 1838 } 1839 1840 //============================================================================= 1841 //------------------------------Value------------------------------------------ 1842 const Type* AbsNode::Value(PhaseGVN* phase) const { 1843 const Type* t1 = phase->type(in(1)); 1844 if (t1 == Type::TOP) return Type::TOP; 1845 1846 switch (t1->base()) { 1847 case Type::Int: { 1848 const TypeInt* ti = t1->is_int(); 1849 if (ti->is_con()) { 1850 return TypeInt::make(uabs(ti->get_con())); 1851 } 1852 break; 1853 } 1854 case Type::Long: { 1855 const TypeLong* tl = t1->is_long(); 1856 if (tl->is_con()) { 1857 return TypeLong::make(uabs(tl->get_con())); 1858 } 1859 break; 1860 } 1861 case Type::FloatCon: 1862 return TypeF::make(abs(t1->getf())); 1863 case Type::DoubleCon: 1864 return TypeD::make(abs(t1->getd())); 1865 default: 1866 break; 1867 } 1868 1869 return bottom_type(); 1870 } 1871 1872 //------------------------------Identity---------------------------------------- 1873 Node* AbsNode::Identity(PhaseGVN* phase) { 1874 Node* in1 = in(1); 1875 // No need to do abs for non-negative values 1876 if (phase->type(in1)->higher_equal(TypeInt::POS) || 1877 phase->type(in1)->higher_equal(TypeLong::POS)) { 1878 return in1; 1879 } 1880 // Convert "abs(abs(x))" into "abs(x)" 1881 if (in1->Opcode() == Opcode()) { 1882 return in1; 1883 } 1884 return this; 1885 } 1886 1887 //------------------------------Ideal------------------------------------------ 1888 Node* AbsNode::Ideal(PhaseGVN* phase, bool can_reshape) { 1889 Node* in1 = in(1); 1890 // Convert "abs(0-x)" into "abs(x)" 1891 if (in1->is_Sub() && phase->type(in1->in(1))->is_zero_type()) { 1892 set_req_X(1, in1->in(2), phase); 1893 return this; 1894 } 1895 return nullptr; 1896 } 1897 1898 //============================================================================= 1899 //------------------------------Value------------------------------------------ 1900 // Compute sqrt 1901 const Type* SqrtDNode::Value(PhaseGVN* phase) const { 1902 const Type *t1 = phase->type( in(1) ); 1903 if( t1 == Type::TOP ) return Type::TOP; 1904 if( t1->base() != Type::DoubleCon ) return Type::DOUBLE; 1905 double d = t1->getd(); 1906 if( d < 0.0 ) return Type::DOUBLE; 1907 return TypeD::make( sqrt( d ) ); 1908 } 1909 1910 const Type* SqrtFNode::Value(PhaseGVN* phase) const { 1911 const Type *t1 = phase->type( in(1) ); 1912 if( t1 == Type::TOP ) return Type::TOP; 1913 if( t1->base() != Type::FloatCon ) return Type::FLOAT; 1914 float f = t1->getf(); 1915 if( f < 0.0f ) return Type::FLOAT; 1916 return TypeF::make( (float)sqrt( (double)f ) ); 1917 } 1918 1919 const Type* ReverseINode::Value(PhaseGVN* phase) const { 1920 const Type *t1 = phase->type( in(1) ); 1921 if (t1 == Type::TOP) { 1922 return Type::TOP; 1923 } 1924 const TypeInt* t1int = t1->isa_int(); 1925 if (t1int && t1int->is_con()) { 1926 jint res = reverse_bits(t1int->get_con()); 1927 return TypeInt::make(res); 1928 } 1929 return bottom_type(); 1930 } 1931 1932 const Type* ReverseLNode::Value(PhaseGVN* phase) const { 1933 const Type *t1 = phase->type( in(1) ); 1934 if (t1 == Type::TOP) { 1935 return Type::TOP; 1936 } 1937 const TypeLong* t1long = t1->isa_long(); 1938 if (t1long && t1long->is_con()) { 1939 jlong res = reverse_bits(t1long->get_con()); 1940 return TypeLong::make(res); 1941 } 1942 return bottom_type(); 1943 } 1944 1945 Node* ReverseINode::Identity(PhaseGVN* phase) { 1946 if (in(1)->Opcode() == Op_ReverseI) { 1947 return in(1)->in(1); 1948 } 1949 return this; 1950 } 1951 1952 Node* ReverseLNode::Identity(PhaseGVN* phase) { 1953 if (in(1)->Opcode() == Op_ReverseL) { 1954 return in(1)->in(1); 1955 } 1956 return this; 1957 }