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/loopnode.hpp" 34 #include "opto/matcher.hpp" 35 #include "opto/movenode.hpp" 36 #include "opto/mulnode.hpp" 37 #include "opto/opcodes.hpp" 38 #include "opto/phaseX.hpp" 39 #include "opto/subnode.hpp" 40 #include "runtime/sharedRuntime.hpp" 41 #include "utilities/moveBits.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 74 return ( phase->type( in(2) )->higher_equal( zero ) ) ? in(1) : this; 75 } 76 77 //------------------------------Value------------------------------------------ 78 // A subtract node differences it's two inputs. 79 const Type* SubNode::Value_common(PhaseTransform *phase) const { 80 const Node* in1 = in(1); 81 const Node* in2 = in(2); 82 // Either input is TOP ==> the result is TOP 83 const Type* t1 = (in1 == this) ? Type::TOP : phase->type(in1); 84 if( t1 == Type::TOP ) return Type::TOP; 85 const Type* t2 = (in2 == this) ? Type::TOP : phase->type(in2); 86 if( t2 == Type::TOP ) return Type::TOP; 87 88 // Not correct for SubFnode and AddFNode (must check for infinity) 89 // Equal? Subtract is zero 90 if (in1->eqv_uncast(in2)) return add_id(); 91 92 // Either input is BOTTOM ==> the result is the local BOTTOM 93 if( t1 == Type::BOTTOM || t2 == Type::BOTTOM ) 94 return bottom_type(); 95 96 return NULL; 97 } 98 99 const Type* SubNode::Value(PhaseGVN* phase) const { 100 const Type* t = Value_common(phase); 101 if (t != NULL) { 102 return t; 103 } 104 const Type* t1 = phase->type(in(1)); 105 const Type* t2 = phase->type(in(2)); 106 return sub(t1,t2); // Local flavor of type subtraction 107 108 } 109 110 SubNode* SubNode::make(Node* in1, Node* in2, BasicType bt) { 111 switch (bt) { 112 case T_INT: 113 return new SubINode(in1, in2); 114 case T_LONG: 115 return new SubLNode(in1, in2); 116 default: 117 fatal("Not implemented for %s", type2name(bt)); 118 } 119 return NULL; 120 } 121 122 //============================================================================= 123 //------------------------------Helper function-------------------------------- 124 125 static bool is_cloop_increment(Node* inc) { 126 precond(inc->Opcode() == Op_AddI || inc->Opcode() == Op_AddL); 127 128 if (!inc->in(1)->is_Phi()) { 129 return false; 130 } 131 const PhiNode* phi = inc->in(1)->as_Phi(); 132 133 if (!phi->region()->is_CountedLoop()) { 134 return false; 135 } 136 137 return inc == phi->region()->as_CountedLoop()->incr(); 138 } 139 140 // Given the expression '(x + C) - v', or 141 // 'v - (x + C)', we examine nodes '+' and 'v': 142 // 143 // 1. Do not convert if '+' is a counted-loop increment, because the '-' is 144 // loop invariant and converting extends the live-range of 'x' to overlap 145 // with the '+', forcing another register to be used in the loop. 146 // 147 // 2. Do not convert if 'v' is a counted-loop induction variable, because 148 // 'x' might be invariant. 149 // 150 static bool ok_to_convert(Node* inc, Node* var) { 151 return !(is_cloop_increment(inc) || var->is_cloop_ind_var()); 152 } 153 154 //------------------------------Ideal------------------------------------------ 155 Node *SubINode::Ideal(PhaseGVN *phase, bool can_reshape){ 156 Node *in1 = in(1); 157 Node *in2 = in(2); 158 uint op1 = in1->Opcode(); 159 uint op2 = in2->Opcode(); 160 161 #ifdef ASSERT 162 // Check for dead loop 163 if ((in1 == this) || (in2 == this) || 164 ((op1 == Op_AddI || op1 == Op_SubI) && 165 ((in1->in(1) == this) || (in1->in(2) == this) || 166 (in1->in(1) == in1) || (in1->in(2) == in1)))) { 167 assert(false, "dead loop in SubINode::Ideal"); 168 } 169 #endif 170 171 const Type *t2 = phase->type( in2 ); 172 if( t2 == Type::TOP ) return NULL; 173 // Convert "x-c0" into "x+ -c0". 174 if( t2->base() == Type::Int ){ // Might be bottom or top... 175 const TypeInt *i = t2->is_int(); 176 if( i->is_con() ) 177 return new AddINode(in1, phase->intcon(-i->get_con())); 178 } 179 180 // Convert "(x+c0) - y" into (x-y) + c0" 181 // Do not collapse (x+c0)-y if "+" is a loop increment or 182 // if "y" is a loop induction variable. 183 if( op1 == Op_AddI && ok_to_convert(in1, in2) ) { 184 const Type *tadd = phase->type( in1->in(2) ); 185 if( tadd->singleton() && tadd != Type::TOP ) { 186 Node *sub2 = phase->transform( new SubINode( in1->in(1), in2 )); 187 return new AddINode( sub2, in1->in(2) ); 188 } 189 } 190 191 // Convert "x - (y+c0)" into "(x-y) - c0" AND 192 // Convert "c1 - (y+c0)" into "(c1-c0) - y" 193 // Need the same check as in above optimization but reversed. 194 if (op2 == Op_AddI 195 && ok_to_convert(in2, in1) 196 && in2->in(2)->Opcode() == Op_ConI) { 197 jint c0 = phase->type(in2->in(2))->isa_int()->get_con(); 198 Node* in21 = in2->in(1); 199 if (in1->Opcode() == Op_ConI) { 200 // Match c1 201 jint c1 = phase->type(in1)->isa_int()->get_con(); 202 Node* sub2 = phase->intcon(java_subtract(c1, c0)); 203 return new SubINode(sub2, in21); 204 } else { 205 // Match x 206 Node* sub2 = phase->transform(new SubINode(in1, in21)); 207 Node* neg_c0 = phase->intcon(-c0); 208 return new AddINode(sub2, neg_c0); 209 } 210 } 211 212 const Type *t1 = phase->type( in1 ); 213 if( t1 == Type::TOP ) return NULL; 214 215 #ifdef ASSERT 216 // Check for dead loop 217 if ((op2 == Op_AddI || op2 == Op_SubI) && 218 ((in2->in(1) == this) || (in2->in(2) == this) || 219 (in2->in(1) == in2) || (in2->in(2) == in2))) { 220 assert(false, "dead loop in SubINode::Ideal"); 221 } 222 #endif 223 224 // Convert "x - (x+y)" into "-y" 225 if (op2 == Op_AddI && in1 == in2->in(1)) { 226 return new SubINode(phase->intcon(0), in2->in(2)); 227 } 228 // Convert "(x-y) - x" into "-y" 229 if (op1 == Op_SubI && in1->in(1) == in2) { 230 return new SubINode(phase->intcon(0), in1->in(2)); 231 } 232 // Convert "x - (y+x)" into "-y" 233 if (op2 == Op_AddI && in1 == in2->in(2)) { 234 return new SubINode(phase->intcon(0), in2->in(1)); 235 } 236 237 // Convert "0 - (x-y)" into "y-x", leave the double negation "-(-y)" to SubNode::Identity(). 238 if (t1 == TypeInt::ZERO && op2 == Op_SubI && phase->type(in2->in(1)) != TypeInt::ZERO) { 239 return new SubINode(in2->in(2), in2->in(1)); 240 } 241 242 // Convert "0 - (x+con)" into "-con-x" 243 jint con; 244 if( t1 == TypeInt::ZERO && op2 == Op_AddI && 245 (con = in2->in(2)->find_int_con(0)) != 0 ) 246 return new SubINode( phase->intcon(-con), in2->in(1) ); 247 248 // Convert "(X+A) - (X+B)" into "A - B" 249 if( op1 == Op_AddI && op2 == Op_AddI && in1->in(1) == in2->in(1) ) 250 return new SubINode( in1->in(2), in2->in(2) ); 251 252 // Convert "(A+X) - (B+X)" into "A - B" 253 if( op1 == Op_AddI && op2 == Op_AddI && in1->in(2) == in2->in(2) ) 254 return new SubINode( in1->in(1), in2->in(1) ); 255 256 // Convert "(A+X) - (X+B)" into "A - B" 257 if( op1 == Op_AddI && op2 == Op_AddI && in1->in(2) == in2->in(1) ) 258 return new SubINode( in1->in(1), in2->in(2) ); 259 260 // Convert "(X+A) - (B+X)" into "A - B" 261 if( op1 == Op_AddI && op2 == Op_AddI && in1->in(1) == in2->in(2) ) 262 return new SubINode( in1->in(2), in2->in(1) ); 263 264 // Convert "A-(B-C)" into (A+C)-B", since add is commutative and generally 265 // nicer to optimize than subtract. 266 if( op2 == Op_SubI && in2->outcnt() == 1) { 267 Node *add1 = phase->transform( new AddINode( in1, in2->in(2) ) ); 268 return new SubINode( add1, in2->in(1) ); 269 } 270 271 // Associative 272 if (op1 == Op_MulI && op2 == Op_MulI) { 273 Node* sub_in1 = NULL; 274 Node* sub_in2 = NULL; 275 Node* mul_in = NULL; 276 277 if (in1->in(1) == in2->in(1)) { 278 // Convert "a*b-a*c into a*(b-c) 279 sub_in1 = in1->in(2); 280 sub_in2 = in2->in(2); 281 mul_in = in1->in(1); 282 } else if (in1->in(2) == in2->in(1)) { 283 // Convert a*b-b*c into b*(a-c) 284 sub_in1 = in1->in(1); 285 sub_in2 = in2->in(2); 286 mul_in = in1->in(2); 287 } else if (in1->in(2) == in2->in(2)) { 288 // Convert a*c-b*c into (a-b)*c 289 sub_in1 = in1->in(1); 290 sub_in2 = in2->in(1); 291 mul_in = in1->in(2); 292 } else if (in1->in(1) == in2->in(2)) { 293 // Convert a*b-c*a into a*(b-c) 294 sub_in1 = in1->in(2); 295 sub_in2 = in2->in(1); 296 mul_in = in1->in(1); 297 } 298 299 if (mul_in != NULL) { 300 Node* sub = phase->transform(new SubINode(sub_in1, sub_in2)); 301 return new MulINode(mul_in, sub); 302 } 303 } 304 305 // Convert "0-(A>>31)" into "(A>>>31)" 306 if ( op2 == Op_RShiftI ) { 307 Node *in21 = in2->in(1); 308 Node *in22 = in2->in(2); 309 const TypeInt *zero = phase->type(in1)->isa_int(); 310 const TypeInt *t21 = phase->type(in21)->isa_int(); 311 const TypeInt *t22 = phase->type(in22)->isa_int(); 312 if ( t21 && t22 && zero == TypeInt::ZERO && t22->is_con(31) ) { 313 return new URShiftINode(in21, in22); 314 } 315 } 316 317 return NULL; 318 } 319 320 //------------------------------sub-------------------------------------------- 321 // A subtract node differences it's two inputs. 322 const Type *SubINode::sub( const Type *t1, const Type *t2 ) const { 323 const TypeInt *r0 = t1->is_int(); // Handy access 324 const TypeInt *r1 = t2->is_int(); 325 int32_t lo = java_subtract(r0->_lo, r1->_hi); 326 int32_t hi = java_subtract(r0->_hi, r1->_lo); 327 328 // We next check for 32-bit overflow. 329 // If that happens, we just assume all integers are possible. 330 if( (((r0->_lo ^ r1->_hi) >= 0) || // lo ends have same signs OR 331 ((r0->_lo ^ lo) >= 0)) && // lo results have same signs AND 332 (((r0->_hi ^ r1->_lo) >= 0) || // hi ends have same signs OR 333 ((r0->_hi ^ hi) >= 0)) ) // hi results have same signs 334 return TypeInt::make(lo,hi,MAX2(r0->_widen,r1->_widen)); 335 else // Overflow; assume all integers 336 return TypeInt::INT; 337 } 338 339 //============================================================================= 340 //------------------------------Ideal------------------------------------------ 341 Node *SubLNode::Ideal(PhaseGVN *phase, bool can_reshape) { 342 Node *in1 = in(1); 343 Node *in2 = in(2); 344 uint op1 = in1->Opcode(); 345 uint op2 = in2->Opcode(); 346 347 #ifdef ASSERT 348 // Check for dead loop 349 if ((in1 == this) || (in2 == this) || 350 ((op1 == Op_AddL || op1 == Op_SubL) && 351 ((in1->in(1) == this) || (in1->in(2) == this) || 352 (in1->in(1) == in1) || (in1->in(2) == in1)))) { 353 assert(false, "dead loop in SubLNode::Ideal"); 354 } 355 #endif 356 357 if( phase->type( in2 ) == Type::TOP ) return NULL; 358 const TypeLong *i = phase->type( in2 )->isa_long(); 359 // Convert "x-c0" into "x+ -c0". 360 if( i && // Might be bottom or top... 361 i->is_con() ) 362 return new AddLNode(in1, phase->longcon(-i->get_con())); 363 364 // Convert "(x+c0) - y" into (x-y) + c0" 365 // Do not collapse (x+c0)-y if "+" is a loop increment or 366 // if "y" is a loop induction variable. 367 if( op1 == Op_AddL && ok_to_convert(in1, in2) ) { 368 Node *in11 = in1->in(1); 369 const Type *tadd = phase->type( in1->in(2) ); 370 if( tadd->singleton() && tadd != Type::TOP ) { 371 Node *sub2 = phase->transform( new SubLNode( in11, in2 )); 372 return new AddLNode( sub2, in1->in(2) ); 373 } 374 } 375 376 // Convert "x - (y+c0)" into "(x-y) - c0" AND 377 // Convert "c1 - (y+c0)" into "(c1-c0) - y" 378 // Need the same check as in above optimization but reversed. 379 if (op2 == Op_AddL 380 && ok_to_convert(in2, in1) 381 && in2->in(2)->Opcode() == Op_ConL) { 382 jlong c0 = phase->type(in2->in(2))->isa_long()->get_con(); 383 Node* in21 = in2->in(1); 384 if (in1->Opcode() == Op_ConL) { 385 // Match c1 386 jlong c1 = phase->type(in1)->isa_long()->get_con(); 387 Node* sub2 = phase->longcon(java_subtract(c1, c0)); 388 return new SubLNode(sub2, in21); 389 } else { 390 Node* sub2 = phase->transform(new SubLNode(in1, in21)); 391 Node* neg_c0 = phase->longcon(-c0); 392 return new AddLNode(sub2, neg_c0); 393 } 394 } 395 396 const Type *t1 = phase->type( in1 ); 397 if( t1 == Type::TOP ) return NULL; 398 399 #ifdef ASSERT 400 // Check for dead loop 401 if ((op2 == Op_AddL || op2 == Op_SubL) && 402 ((in2->in(1) == this) || (in2->in(2) == this) || 403 (in2->in(1) == in2) || (in2->in(2) == in2))) { 404 assert(false, "dead loop in SubLNode::Ideal"); 405 } 406 #endif 407 408 // Convert "x - (x+y)" into "-y" 409 if (op2 == Op_AddL && in1 == in2->in(1)) { 410 return new SubLNode(phase->makecon(TypeLong::ZERO), in2->in(2)); 411 } 412 // Convert "(x-y) - x" into "-y" 413 if (op1 == Op_SubL && in1->in(1) == in2) { 414 return new SubLNode(phase->makecon(TypeLong::ZERO), in1->in(2)); 415 } 416 // Convert "x - (y+x)" into "-y" 417 if (op2 == Op_AddL && in1 == in2->in(2)) { 418 return new SubLNode(phase->makecon(TypeLong::ZERO), in2->in(1)); 419 } 420 421 // Convert "0 - (x-y)" into "y-x", leave the double negation "-(-y)" to SubNode::Identity. 422 if (t1 == TypeLong::ZERO && op2 == Op_SubL && phase->type(in2->in(1)) != TypeLong::ZERO) { 423 return new SubLNode(in2->in(2), in2->in(1)); 424 } 425 426 // Convert "(X+A) - (X+B)" into "A - B" 427 if( op1 == Op_AddL && op2 == Op_AddL && in1->in(1) == in2->in(1) ) 428 return new SubLNode( in1->in(2), in2->in(2) ); 429 430 // Convert "(A+X) - (B+X)" into "A - B" 431 if( op1 == Op_AddL && op2 == Op_AddL && in1->in(2) == in2->in(2) ) 432 return new SubLNode( in1->in(1), in2->in(1) ); 433 434 // Convert "(A+X) - (X+B)" into "A - B" 435 if( op1 == Op_AddL && op2 == Op_AddL && in1->in(2) == in2->in(1) ) 436 return new SubLNode( in1->in(1), in2->in(2) ); 437 438 // Convert "(X+A) - (B+X)" into "A - B" 439 if( op1 == Op_AddL && op2 == Op_AddL && in1->in(1) == in2->in(2) ) 440 return new SubLNode( in1->in(2), in2->in(1) ); 441 442 // Convert "A-(B-C)" into (A+C)-B" 443 if( op2 == Op_SubL && in2->outcnt() == 1) { 444 Node *add1 = phase->transform( new AddLNode( in1, in2->in(2) ) ); 445 return new SubLNode( add1, in2->in(1) ); 446 } 447 448 // Associative 449 if (op1 == Op_MulL && op2 == Op_MulL) { 450 Node* sub_in1 = NULL; 451 Node* sub_in2 = NULL; 452 Node* mul_in = NULL; 453 454 if (in1->in(1) == in2->in(1)) { 455 // Convert "a*b-a*c into a*(b+c) 456 sub_in1 = in1->in(2); 457 sub_in2 = in2->in(2); 458 mul_in = in1->in(1); 459 } else if (in1->in(2) == in2->in(1)) { 460 // Convert a*b-b*c into b*(a-c) 461 sub_in1 = in1->in(1); 462 sub_in2 = in2->in(2); 463 mul_in = in1->in(2); 464 } else if (in1->in(2) == in2->in(2)) { 465 // Convert a*c-b*c into (a-b)*c 466 sub_in1 = in1->in(1); 467 sub_in2 = in2->in(1); 468 mul_in = in1->in(2); 469 } else if (in1->in(1) == in2->in(2)) { 470 // Convert a*b-c*a into a*(b-c) 471 sub_in1 = in1->in(2); 472 sub_in2 = in2->in(1); 473 mul_in = in1->in(1); 474 } 475 476 if (mul_in != NULL) { 477 Node* sub = phase->transform(new SubLNode(sub_in1, sub_in2)); 478 return new MulLNode(mul_in, sub); 479 } 480 } 481 482 // Convert "0L-(A>>63)" into "(A>>>63)" 483 if ( op2 == Op_RShiftL ) { 484 Node *in21 = in2->in(1); 485 Node *in22 = in2->in(2); 486 const TypeLong *zero = phase->type(in1)->isa_long(); 487 const TypeLong *t21 = phase->type(in21)->isa_long(); 488 const TypeInt *t22 = phase->type(in22)->isa_int(); 489 if ( t21 && t22 && zero == TypeLong::ZERO && t22->is_con(63) ) { 490 return new URShiftLNode(in21, in22); 491 } 492 } 493 494 return NULL; 495 } 496 497 //------------------------------sub-------------------------------------------- 498 // A subtract node differences it's two inputs. 499 const Type *SubLNode::sub( const Type *t1, const Type *t2 ) const { 500 const TypeLong *r0 = t1->is_long(); // Handy access 501 const TypeLong *r1 = t2->is_long(); 502 jlong lo = java_subtract(r0->_lo, r1->_hi); 503 jlong hi = java_subtract(r0->_hi, r1->_lo); 504 505 // We next check for 32-bit overflow. 506 // If that happens, we just assume all integers are possible. 507 if( (((r0->_lo ^ r1->_hi) >= 0) || // lo ends have same signs OR 508 ((r0->_lo ^ lo) >= 0)) && // lo results have same signs AND 509 (((r0->_hi ^ r1->_lo) >= 0) || // hi ends have same signs OR 510 ((r0->_hi ^ hi) >= 0)) ) // hi results have same signs 511 return TypeLong::make(lo,hi,MAX2(r0->_widen,r1->_widen)); 512 else // Overflow; assume all integers 513 return TypeLong::LONG; 514 } 515 516 //============================================================================= 517 //------------------------------Value------------------------------------------ 518 // A subtract node differences its two inputs. 519 const Type* SubFPNode::Value(PhaseGVN* phase) const { 520 const Node* in1 = in(1); 521 const Node* in2 = in(2); 522 // Either input is TOP ==> the result is TOP 523 const Type* t1 = (in1 == this) ? Type::TOP : phase->type(in1); 524 if( t1 == Type::TOP ) return Type::TOP; 525 const Type* t2 = (in2 == this) ? Type::TOP : phase->type(in2); 526 if( t2 == Type::TOP ) return Type::TOP; 527 528 // if both operands are infinity of same sign, the result is NaN; do 529 // not replace with zero 530 if (t1->is_finite() && t2->is_finite() && in1 == in2) { 531 return add_id(); 532 } 533 534 // Either input is BOTTOM ==> the result is the local BOTTOM 535 const Type *bot = bottom_type(); 536 if( (t1 == bot) || (t2 == bot) || 537 (t1 == Type::BOTTOM) || (t2 == Type::BOTTOM) ) 538 return bot; 539 540 return sub(t1,t2); // Local flavor of type subtraction 541 } 542 543 544 //============================================================================= 545 //------------------------------Ideal------------------------------------------ 546 Node *SubFNode::Ideal(PhaseGVN *phase, bool can_reshape) { 547 const Type *t2 = phase->type( in(2) ); 548 // Convert "x-c0" into "x+ -c0". 549 if( t2->base() == Type::FloatCon ) { // Might be bottom or top... 550 // return new (phase->C, 3) AddFNode(in(1), phase->makecon( TypeF::make(-t2->getf()) ) ); 551 } 552 553 // Cannot replace 0.0-X with -X because a 'fsub' bytecode computes 554 // 0.0-0.0 as +0.0, while a 'fneg' bytecode computes -0.0. 555 //if( phase->type(in(1)) == TypeF::ZERO ) 556 //return new (phase->C, 2) NegFNode(in(2)); 557 558 return NULL; 559 } 560 561 //------------------------------sub-------------------------------------------- 562 // A subtract node differences its two inputs. 563 const Type *SubFNode::sub( const Type *t1, const Type *t2 ) const { 564 // no folding if one of operands is infinity or NaN, do not do constant folding 565 if( g_isfinite(t1->getf()) && g_isfinite(t2->getf()) ) { 566 return TypeF::make( t1->getf() - t2->getf() ); 567 } 568 else if( g_isnan(t1->getf()) ) { 569 return t1; 570 } 571 else if( g_isnan(t2->getf()) ) { 572 return t2; 573 } 574 else { 575 return Type::FLOAT; 576 } 577 } 578 579 //============================================================================= 580 //------------------------------Ideal------------------------------------------ 581 Node *SubDNode::Ideal(PhaseGVN *phase, bool can_reshape){ 582 const Type *t2 = phase->type( in(2) ); 583 // Convert "x-c0" into "x+ -c0". 584 if( t2->base() == Type::DoubleCon ) { // Might be bottom or top... 585 // return new (phase->C, 3) AddDNode(in(1), phase->makecon( TypeD::make(-t2->getd()) ) ); 586 } 587 588 // Cannot replace 0.0-X with -X because a 'dsub' bytecode computes 589 // 0.0-0.0 as +0.0, while a 'dneg' bytecode computes -0.0. 590 //if( phase->type(in(1)) == TypeD::ZERO ) 591 //return new (phase->C, 2) NegDNode(in(2)); 592 593 return NULL; 594 } 595 596 //------------------------------sub-------------------------------------------- 597 // A subtract node differences its two inputs. 598 const Type *SubDNode::sub( const Type *t1, const Type *t2 ) const { 599 // no folding if one of operands is infinity or NaN, do not do constant folding 600 if( g_isfinite(t1->getd()) && g_isfinite(t2->getd()) ) { 601 return TypeD::make( t1->getd() - t2->getd() ); 602 } 603 else if( g_isnan(t1->getd()) ) { 604 return t1; 605 } 606 else if( g_isnan(t2->getd()) ) { 607 return t2; 608 } 609 else { 610 return Type::DOUBLE; 611 } 612 } 613 614 //============================================================================= 615 //------------------------------Idealize--------------------------------------- 616 // Unlike SubNodes, compare must still flatten return value to the 617 // range -1, 0, 1. 618 // And optimizations like those for (X + Y) - X fail if overflow happens. 619 Node* CmpNode::Identity(PhaseGVN* phase) { 620 return this; 621 } 622 623 CmpNode *CmpNode::make(Node *in1, Node *in2, BasicType bt, bool unsigned_comp) { 624 switch (bt) { 625 case T_INT: 626 if (unsigned_comp) { 627 return new CmpUNode(in1, in2); 628 } 629 return new CmpINode(in1, in2); 630 case T_LONG: 631 if (unsigned_comp) { 632 return new CmpULNode(in1, in2); 633 } 634 return new CmpLNode(in1, in2); 635 default: 636 fatal("Not implemented for %s", type2name(bt)); 637 } 638 return NULL; 639 } 640 641 //============================================================================= 642 //------------------------------cmp-------------------------------------------- 643 // Simplify a CmpI (compare 2 integers) node, based on local information. 644 // If both inputs are constants, compare them. 645 const Type *CmpINode::sub( const Type *t1, const Type *t2 ) const { 646 const TypeInt *r0 = t1->is_int(); // Handy access 647 const TypeInt *r1 = t2->is_int(); 648 649 if( r0->_hi < r1->_lo ) // Range is always low? 650 return TypeInt::CC_LT; 651 else if( r0->_lo > r1->_hi ) // Range is always high? 652 return TypeInt::CC_GT; 653 654 else if( r0->is_con() && r1->is_con() ) { // comparing constants? 655 assert(r0->get_con() == r1->get_con(), "must be equal"); 656 return TypeInt::CC_EQ; // Equal results. 657 } else if( r0->_hi == r1->_lo ) // Range is never high? 658 return TypeInt::CC_LE; 659 else if( r0->_lo == r1->_hi ) // Range is never low? 660 return TypeInt::CC_GE; 661 return TypeInt::CC; // else use worst case results 662 } 663 664 // Simplify a CmpU (compare 2 integers) node, based on local information. 665 // If both inputs are constants, compare them. 666 const Type *CmpUNode::sub( const Type *t1, const Type *t2 ) const { 667 assert(!t1->isa_ptr(), "obsolete usage of CmpU"); 668 669 // comparing two unsigned ints 670 const TypeInt *r0 = t1->is_int(); // Handy access 671 const TypeInt *r1 = t2->is_int(); 672 673 // Current installed version 674 // Compare ranges for non-overlap 675 juint lo0 = r0->_lo; 676 juint hi0 = r0->_hi; 677 juint lo1 = r1->_lo; 678 juint hi1 = r1->_hi; 679 680 // If either one has both negative and positive values, 681 // it therefore contains both 0 and -1, and since [0..-1] is the 682 // full unsigned range, the type must act as an unsigned bottom. 683 bool bot0 = ((jint)(lo0 ^ hi0) < 0); 684 bool bot1 = ((jint)(lo1 ^ hi1) < 0); 685 686 if (bot0 || bot1) { 687 // All unsigned values are LE -1 and GE 0. 688 if (lo0 == 0 && hi0 == 0) { 689 return TypeInt::CC_LE; // 0 <= bot 690 } else if ((jint)lo0 == -1 && (jint)hi0 == -1) { 691 return TypeInt::CC_GE; // -1 >= bot 692 } else if (lo1 == 0 && hi1 == 0) { 693 return TypeInt::CC_GE; // bot >= 0 694 } else if ((jint)lo1 == -1 && (jint)hi1 == -1) { 695 return TypeInt::CC_LE; // bot <= -1 696 } 697 } else { 698 // We can use ranges of the form [lo..hi] if signs are the same. 699 assert(lo0 <= hi0 && lo1 <= hi1, "unsigned ranges are valid"); 700 // results are reversed, '-' > '+' for unsigned compare 701 if (hi0 < lo1) { 702 return TypeInt::CC_LT; // smaller 703 } else if (lo0 > hi1) { 704 return TypeInt::CC_GT; // greater 705 } else if (hi0 == lo1 && lo0 == hi1) { 706 return TypeInt::CC_EQ; // Equal results 707 } else if (lo0 >= hi1) { 708 return TypeInt::CC_GE; 709 } else if (hi0 <= lo1) { 710 // Check for special case in Hashtable::get. (See below.) 711 if ((jint)lo0 >= 0 && (jint)lo1 >= 0 && is_index_range_check()) 712 return TypeInt::CC_LT; 713 return TypeInt::CC_LE; 714 } 715 } 716 // Check for special case in Hashtable::get - the hash index is 717 // mod'ed to the table size so the following range check is useless. 718 // Check for: (X Mod Y) CmpU Y, where the mod result and Y both have 719 // to be positive. 720 // (This is a gross hack, since the sub method never 721 // looks at the structure of the node in any other case.) 722 if ((jint)lo0 >= 0 && (jint)lo1 >= 0 && is_index_range_check()) 723 return TypeInt::CC_LT; 724 return TypeInt::CC; // else use worst case results 725 } 726 727 const Type* CmpUNode::Value(PhaseGVN* phase) const { 728 const Type* t = SubNode::Value_common(phase); 729 if (t != NULL) { 730 return t; 731 } 732 const Node* in1 = in(1); 733 const Node* in2 = in(2); 734 const Type* t1 = phase->type(in1); 735 const Type* t2 = phase->type(in2); 736 assert(t1->isa_int(), "CmpU has only Int type inputs"); 737 if (t2 == TypeInt::INT) { // Compare to bottom? 738 return bottom_type(); 739 } 740 uint in1_op = in1->Opcode(); 741 if (in1_op == Op_AddI || in1_op == Op_SubI) { 742 // The problem rise when result of AddI(SubI) may overflow 743 // signed integer value. Let say the input type is 744 // [256, maxint] then +128 will create 2 ranges due to 745 // overflow: [minint, minint+127] and [384, maxint]. 746 // But C2 type system keep only 1 type range and as result 747 // it use general [minint, maxint] for this case which we 748 // can't optimize. 749 // 750 // Make 2 separate type ranges based on types of AddI(SubI) inputs 751 // and compare results of their compare. If results are the same 752 // CmpU node can be optimized. 753 const Node* in11 = in1->in(1); 754 const Node* in12 = in1->in(2); 755 const Type* t11 = (in11 == in1) ? Type::TOP : phase->type(in11); 756 const Type* t12 = (in12 == in1) ? Type::TOP : phase->type(in12); 757 // Skip cases when input types are top or bottom. 758 if ((t11 != Type::TOP) && (t11 != TypeInt::INT) && 759 (t12 != Type::TOP) && (t12 != TypeInt::INT)) { 760 const TypeInt *r0 = t11->is_int(); 761 const TypeInt *r1 = t12->is_int(); 762 jlong lo_r0 = r0->_lo; 763 jlong hi_r0 = r0->_hi; 764 jlong lo_r1 = r1->_lo; 765 jlong hi_r1 = r1->_hi; 766 if (in1_op == Op_SubI) { 767 jlong tmp = hi_r1; 768 hi_r1 = -lo_r1; 769 lo_r1 = -tmp; 770 // Note, for substructing [minint,x] type range 771 // long arithmetic provides correct overflow answer. 772 // The confusion come from the fact that in 32-bit 773 // -minint == minint but in 64-bit -minint == maxint+1. 774 } 775 jlong lo_long = lo_r0 + lo_r1; 776 jlong hi_long = hi_r0 + hi_r1; 777 int lo_tr1 = min_jint; 778 int hi_tr1 = (int)hi_long; 779 int lo_tr2 = (int)lo_long; 780 int hi_tr2 = max_jint; 781 bool underflow = lo_long != (jlong)lo_tr2; 782 bool overflow = hi_long != (jlong)hi_tr1; 783 // Use sub(t1, t2) when there is no overflow (one type range) 784 // or when both overflow and underflow (too complex). 785 if ((underflow != overflow) && (hi_tr1 < lo_tr2)) { 786 // Overflow only on one boundary, compare 2 separate type ranges. 787 int w = MAX2(r0->_widen, r1->_widen); // _widen does not matter here 788 const TypeInt* tr1 = TypeInt::make(lo_tr1, hi_tr1, w); 789 const TypeInt* tr2 = TypeInt::make(lo_tr2, hi_tr2, w); 790 const TypeInt* cmp1 = sub(tr1, t2)->is_int(); 791 const TypeInt* cmp2 = sub(tr2, t2)->is_int(); 792 // compute union, so that cmp handles all possible results from the two cases 793 return cmp1->meet(cmp2); 794 } 795 } 796 } 797 798 return sub(t1, t2); // Local flavor of type subtraction 799 } 800 801 bool CmpUNode::is_index_range_check() const { 802 // Check for the "(X ModI Y) CmpU Y" shape 803 return (in(1)->Opcode() == Op_ModI && 804 in(1)->in(2)->eqv_uncast(in(2))); 805 } 806 807 //------------------------------Idealize--------------------------------------- 808 Node *CmpINode::Ideal( PhaseGVN *phase, bool can_reshape ) { 809 if (phase->type(in(2))->higher_equal(TypeInt::ZERO)) { 810 switch (in(1)->Opcode()) { 811 case Op_CmpU3: // Collapse a CmpU3/CmpI into a CmpU 812 return new CmpUNode(in(1)->in(1),in(1)->in(2)); 813 case Op_CmpL3: // Collapse a CmpL3/CmpI into a CmpL 814 return new CmpLNode(in(1)->in(1),in(1)->in(2)); 815 case Op_CmpUL3: // Collapse a CmpUL3/CmpI into a CmpUL 816 return new CmpULNode(in(1)->in(1),in(1)->in(2)); 817 case Op_CmpF3: // Collapse a CmpF3/CmpI into a CmpF 818 return new CmpFNode(in(1)->in(1),in(1)->in(2)); 819 case Op_CmpD3: // Collapse a CmpD3/CmpI into a CmpD 820 return new CmpDNode(in(1)->in(1),in(1)->in(2)); 821 //case Op_SubI: 822 // If (x - y) cannot overflow, then ((x - y) <?> 0) 823 // can be turned into (x <?> y). 824 // This is handled (with more general cases) by Ideal_sub_algebra. 825 } 826 } 827 return NULL; // No change 828 } 829 830 Node *CmpLNode::Ideal( PhaseGVN *phase, bool can_reshape ) { 831 const TypeLong *t2 = phase->type(in(2))->isa_long(); 832 if (Opcode() == Op_CmpL && in(1)->Opcode() == Op_ConvI2L && t2 && t2->is_con()) { 833 const jlong con = t2->get_con(); 834 if (con >= min_jint && con <= max_jint) { 835 return new CmpINode(in(1)->in(1), phase->intcon((jint)con)); 836 } 837 } 838 return NULL; 839 } 840 841 //============================================================================= 842 // Simplify a CmpL (compare 2 longs ) node, based on local information. 843 // If both inputs are constants, compare them. 844 const Type *CmpLNode::sub( const Type *t1, const Type *t2 ) const { 845 const TypeLong *r0 = t1->is_long(); // Handy access 846 const TypeLong *r1 = t2->is_long(); 847 848 if( r0->_hi < r1->_lo ) // Range is always low? 849 return TypeInt::CC_LT; 850 else if( r0->_lo > r1->_hi ) // Range is always high? 851 return TypeInt::CC_GT; 852 853 else if( r0->is_con() && r1->is_con() ) { // comparing constants? 854 assert(r0->get_con() == r1->get_con(), "must be equal"); 855 return TypeInt::CC_EQ; // Equal results. 856 } else if( r0->_hi == r1->_lo ) // Range is never high? 857 return TypeInt::CC_LE; 858 else if( r0->_lo == r1->_hi ) // Range is never low? 859 return TypeInt::CC_GE; 860 return TypeInt::CC; // else use worst case results 861 } 862 863 864 // Simplify a CmpUL (compare 2 unsigned longs) node, based on local information. 865 // If both inputs are constants, compare them. 866 const Type* CmpULNode::sub(const Type* t1, const Type* t2) const { 867 assert(!t1->isa_ptr(), "obsolete usage of CmpUL"); 868 869 // comparing two unsigned longs 870 const TypeLong* r0 = t1->is_long(); // Handy access 871 const TypeLong* r1 = t2->is_long(); 872 873 // Current installed version 874 // Compare ranges for non-overlap 875 julong lo0 = r0->_lo; 876 julong hi0 = r0->_hi; 877 julong lo1 = r1->_lo; 878 julong hi1 = r1->_hi; 879 880 // If either one has both negative and positive values, 881 // it therefore contains both 0 and -1, and since [0..-1] is the 882 // full unsigned range, the type must act as an unsigned bottom. 883 bool bot0 = ((jlong)(lo0 ^ hi0) < 0); 884 bool bot1 = ((jlong)(lo1 ^ hi1) < 0); 885 886 if (bot0 || bot1) { 887 // All unsigned values are LE -1 and GE 0. 888 if (lo0 == 0 && hi0 == 0) { 889 return TypeInt::CC_LE; // 0 <= bot 890 } else if ((jlong)lo0 == -1 && (jlong)hi0 == -1) { 891 return TypeInt::CC_GE; // -1 >= bot 892 } else if (lo1 == 0 && hi1 == 0) { 893 return TypeInt::CC_GE; // bot >= 0 894 } else if ((jlong)lo1 == -1 && (jlong)hi1 == -1) { 895 return TypeInt::CC_LE; // bot <= -1 896 } 897 } else { 898 // We can use ranges of the form [lo..hi] if signs are the same. 899 assert(lo0 <= hi0 && lo1 <= hi1, "unsigned ranges are valid"); 900 // results are reversed, '-' > '+' for unsigned compare 901 if (hi0 < lo1) { 902 return TypeInt::CC_LT; // smaller 903 } else if (lo0 > hi1) { 904 return TypeInt::CC_GT; // greater 905 } else if (hi0 == lo1 && lo0 == hi1) { 906 return TypeInt::CC_EQ; // Equal results 907 } else if (lo0 >= hi1) { 908 return TypeInt::CC_GE; 909 } else if (hi0 <= lo1) { 910 return TypeInt::CC_LE; 911 } 912 } 913 914 return TypeInt::CC; // else use worst case results 915 } 916 917 //============================================================================= 918 //------------------------------sub-------------------------------------------- 919 // Simplify an CmpP (compare 2 pointers) node, based on local information. 920 // If both inputs are constants, compare them. 921 const Type *CmpPNode::sub( const Type *t1, const Type *t2 ) const { 922 const TypePtr *r0 = t1->is_ptr(); // Handy access 923 const TypePtr *r1 = t2->is_ptr(); 924 925 // Undefined inputs makes for an undefined result 926 if( TypePtr::above_centerline(r0->_ptr) || 927 TypePtr::above_centerline(r1->_ptr) ) 928 return Type::TOP; 929 930 if (r0 == r1 && r0->singleton()) { 931 // Equal pointer constants (klasses, nulls, etc.) 932 return TypeInt::CC_EQ; 933 } 934 935 // See if it is 2 unrelated classes. 936 const TypeOopPtr* p0 = r0->isa_oopptr(); 937 const TypeOopPtr* p1 = r1->isa_oopptr(); 938 const TypeKlassPtr* k0 = r0->isa_klassptr(); 939 const TypeKlassPtr* k1 = r1->isa_klassptr(); 940 if ((p0 && p1) || (k0 && k1)) { 941 if (p0 && p1) { 942 Node* in1 = in(1)->uncast(); 943 Node* in2 = in(2)->uncast(); 944 AllocateNode* alloc1 = AllocateNode::Ideal_allocation(in1, NULL); 945 AllocateNode* alloc2 = AllocateNode::Ideal_allocation(in2, NULL); 946 if (MemNode::detect_ptr_independence(in1, alloc1, in2, alloc2, NULL)) { 947 return TypeInt::CC_GT; // different pointers 948 } 949 } 950 bool xklass0 = p0 ? p0->klass_is_exact() : k0->klass_is_exact(); 951 bool xklass1 = p1 ? p1->klass_is_exact() : k1->klass_is_exact(); 952 bool unrelated_classes = false; 953 954 if ((p0 && p0->is_same_java_type_as(p1)) || 955 (k0 && k0->is_same_java_type_as(k1))) { 956 } else if ((p0 && !p1->maybe_java_subtype_of(p0) && !p0->maybe_java_subtype_of(p1)) || 957 (k0 && !k1->maybe_java_subtype_of(k0) && !k0->maybe_java_subtype_of(k1))) { 958 unrelated_classes = true; 959 } else if ((p0 && !p1->maybe_java_subtype_of(p0)) || 960 (k0 && !k1->maybe_java_subtype_of(k0))) { 961 unrelated_classes = xklass1; 962 } else if ((p0 && !p0->maybe_java_subtype_of(p1)) || 963 (k0 && !k0->maybe_java_subtype_of(k1))) { 964 unrelated_classes = xklass0; 965 } 966 967 if (unrelated_classes) { 968 // The oops classes are known to be unrelated. If the joined PTRs of 969 // two oops is not Null and not Bottom, then we are sure that one 970 // of the two oops is non-null, and the comparison will always fail. 971 TypePtr::PTR jp = r0->join_ptr(r1->_ptr); 972 if (jp != TypePtr::Null && jp != TypePtr::BotPTR) { 973 return TypeInt::CC_GT; 974 } 975 } 976 } 977 978 // Known constants can be compared exactly 979 // Null can be distinguished from any NotNull pointers 980 // Unknown inputs makes an unknown result 981 if( r0->singleton() ) { 982 intptr_t bits0 = r0->get_con(); 983 if( r1->singleton() ) 984 return bits0 == r1->get_con() ? TypeInt::CC_EQ : TypeInt::CC_GT; 985 return ( r1->_ptr == TypePtr::NotNull && bits0==0 ) ? TypeInt::CC_GT : TypeInt::CC; 986 } else if( r1->singleton() ) { 987 intptr_t bits1 = r1->get_con(); 988 return ( r0->_ptr == TypePtr::NotNull && bits1==0 ) ? TypeInt::CC_GT : TypeInt::CC; 989 } else 990 return TypeInt::CC; 991 } 992 993 static inline Node* isa_java_mirror_load(PhaseGVN* phase, Node* n) { 994 // Return the klass node for (indirect load from OopHandle) 995 // LoadBarrier?(LoadP(LoadP(AddP(foo:Klass, #java_mirror)))) 996 // or NULL if not matching. 997 BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2(); 998 n = bs->step_over_gc_barrier(n); 999 1000 if (n->Opcode() != Op_LoadP) return NULL; 1001 1002 const TypeInstPtr* tp = phase->type(n)->isa_instptr(); 1003 if (!tp || tp->instance_klass() != phase->C->env()->Class_klass()) return NULL; 1004 1005 Node* adr = n->in(MemNode::Address); 1006 // First load from OopHandle: ((OopHandle)mirror)->resolve(); may need barrier. 1007 if (adr->Opcode() != Op_LoadP || !phase->type(adr)->isa_rawptr()) return NULL; 1008 adr = adr->in(MemNode::Address); 1009 1010 intptr_t off = 0; 1011 Node* k = AddPNode::Ideal_base_and_offset(adr, phase, off); 1012 if (k == NULL) return NULL; 1013 const TypeKlassPtr* tkp = phase->type(k)->isa_klassptr(); 1014 if (!tkp || off != in_bytes(Klass::java_mirror_offset())) return NULL; 1015 1016 // We've found the klass node of a Java mirror load. 1017 return k; 1018 } 1019 1020 static inline Node* isa_const_java_mirror(PhaseGVN* phase, Node* n) { 1021 // for ConP(Foo.class) return ConP(Foo.klass) 1022 // otherwise return NULL 1023 if (!n->is_Con()) return NULL; 1024 1025 const TypeInstPtr* tp = phase->type(n)->isa_instptr(); 1026 if (!tp) return NULL; 1027 1028 ciType* mirror_type = tp->java_mirror_type(); 1029 // TypeInstPtr::java_mirror_type() returns non-NULL for compile- 1030 // time Class constants only. 1031 if (!mirror_type) return NULL; 1032 1033 // x.getClass() == int.class can never be true (for all primitive types) 1034 // Return a ConP(NULL) node for this case. 1035 if (mirror_type->is_classless()) { 1036 return phase->makecon(TypePtr::NULL_PTR); 1037 } 1038 1039 // return the ConP(Foo.klass) 1040 assert(mirror_type->is_klass(), "mirror_type should represent a Klass*"); 1041 return phase->makecon(TypeKlassPtr::make(mirror_type->as_klass())); 1042 } 1043 1044 //------------------------------Ideal------------------------------------------ 1045 // Normalize comparisons between Java mirror loads to compare the klass instead. 1046 // 1047 // Also check for the case of comparing an unknown klass loaded from the primary 1048 // super-type array vs a known klass with no subtypes. This amounts to 1049 // checking to see an unknown klass subtypes a known klass with no subtypes; 1050 // this only happens on an exact match. We can shorten this test by 1 load. 1051 Node *CmpPNode::Ideal( PhaseGVN *phase, bool can_reshape ) { 1052 // Normalize comparisons between Java mirrors into comparisons of the low- 1053 // level klass, where a dependent load could be shortened. 1054 // 1055 // The new pattern has a nice effect of matching the same pattern used in the 1056 // fast path of instanceof/checkcast/Class.isInstance(), which allows 1057 // redundant exact type check be optimized away by GVN. 1058 // For example, in 1059 // if (x.getClass() == Foo.class) { 1060 // Foo foo = (Foo) x; 1061 // // ... use a ... 1062 // } 1063 // a CmpPNode could be shared between if_acmpne and checkcast 1064 { 1065 Node* k1 = isa_java_mirror_load(phase, in(1)); 1066 Node* k2 = isa_java_mirror_load(phase, in(2)); 1067 Node* conk2 = isa_const_java_mirror(phase, in(2)); 1068 1069 if (k1 && (k2 || conk2)) { 1070 Node* lhs = k1; 1071 Node* rhs = (k2 != NULL) ? k2 : conk2; 1072 set_req_X(1, lhs, phase); 1073 set_req_X(2, rhs, phase); 1074 return this; 1075 } 1076 } 1077 1078 // Constant pointer on right? 1079 const TypeKlassPtr* t2 = phase->type(in(2))->isa_klassptr(); 1080 if (t2 == NULL || !t2->klass_is_exact()) 1081 return NULL; 1082 // Get the constant klass we are comparing to. 1083 ciKlass* superklass = t2->exact_klass(); 1084 1085 // Now check for LoadKlass on left. 1086 Node* ldk1 = in(1); 1087 if (ldk1->is_DecodeNKlass()) { 1088 ldk1 = ldk1->in(1); 1089 if (ldk1->Opcode() != Op_LoadNKlass ) 1090 return NULL; 1091 } else if (ldk1->Opcode() != Op_LoadKlass ) 1092 return NULL; 1093 // Take apart the address of the LoadKlass: 1094 Node* adr1 = ldk1->in(MemNode::Address); 1095 intptr_t con2 = 0; 1096 Node* ldk2 = AddPNode::Ideal_base_and_offset(adr1, phase, con2); 1097 if (ldk2 == NULL) 1098 return NULL; 1099 if (con2 == oopDesc::klass_offset_in_bytes()) { 1100 // We are inspecting an object's concrete class. 1101 // Short-circuit the check if the query is abstract. 1102 if (superklass->is_interface() || 1103 superklass->is_abstract()) { 1104 // Make it come out always false: 1105 this->set_req(2, phase->makecon(TypePtr::NULL_PTR)); 1106 return this; 1107 } 1108 } 1109 1110 // Check for a LoadKlass from primary supertype array. 1111 // Any nested loadklass from loadklass+con must be from the p.s. array. 1112 if (ldk2->is_DecodeNKlass()) { 1113 // Keep ldk2 as DecodeN since it could be used in CmpP below. 1114 if (ldk2->in(1)->Opcode() != Op_LoadNKlass ) 1115 return NULL; 1116 } else if (ldk2->Opcode() != Op_LoadKlass) 1117 return NULL; 1118 1119 // Verify that we understand the situation 1120 if (con2 != (intptr_t) superklass->super_check_offset()) 1121 return NULL; // Might be element-klass loading from array klass 1122 1123 // If 'superklass' has no subklasses and is not an interface, then we are 1124 // assured that the only input which will pass the type check is 1125 // 'superklass' itself. 1126 // 1127 // We could be more liberal here, and allow the optimization on interfaces 1128 // which have a single implementor. This would require us to increase the 1129 // expressiveness of the add_dependency() mechanism. 1130 // %%% Do this after we fix TypeOopPtr: Deps are expressive enough now. 1131 1132 // Object arrays must have their base element have no subtypes 1133 while (superklass->is_obj_array_klass()) { 1134 ciType* elem = superklass->as_obj_array_klass()->element_type(); 1135 superklass = elem->as_klass(); 1136 } 1137 if (superklass->is_instance_klass()) { 1138 ciInstanceKlass* ik = superklass->as_instance_klass(); 1139 if (ik->has_subklass() || ik->is_interface()) return NULL; 1140 // Add a dependency if there is a chance that a subclass will be added later. 1141 if (!ik->is_final()) { 1142 phase->C->dependencies()->assert_leaf_type(ik); 1143 } 1144 } 1145 1146 // Bypass the dependent load, and compare directly 1147 this->set_req(1,ldk2); 1148 1149 return this; 1150 } 1151 1152 //============================================================================= 1153 //------------------------------sub-------------------------------------------- 1154 // Simplify an CmpN (compare 2 pointers) node, based on local information. 1155 // If both inputs are constants, compare them. 1156 const Type *CmpNNode::sub( const Type *t1, const Type *t2 ) const { 1157 ShouldNotReachHere(); 1158 return bottom_type(); 1159 } 1160 1161 //------------------------------Ideal------------------------------------------ 1162 Node *CmpNNode::Ideal( PhaseGVN *phase, bool can_reshape ) { 1163 return NULL; 1164 } 1165 1166 //============================================================================= 1167 //------------------------------Value------------------------------------------ 1168 // Simplify an CmpF (compare 2 floats ) node, based on local information. 1169 // If both inputs are constants, compare them. 1170 const Type* CmpFNode::Value(PhaseGVN* phase) const { 1171 const Node* in1 = in(1); 1172 const Node* in2 = in(2); 1173 // Either input is TOP ==> the result is TOP 1174 const Type* t1 = (in1 == this) ? Type::TOP : phase->type(in1); 1175 if( t1 == Type::TOP ) return Type::TOP; 1176 const Type* t2 = (in2 == this) ? Type::TOP : phase->type(in2); 1177 if( t2 == Type::TOP ) return Type::TOP; 1178 1179 // Not constants? Don't know squat - even if they are the same 1180 // value! If they are NaN's they compare to LT instead of EQ. 1181 const TypeF *tf1 = t1->isa_float_constant(); 1182 const TypeF *tf2 = t2->isa_float_constant(); 1183 if( !tf1 || !tf2 ) return TypeInt::CC; 1184 1185 // This implements the Java bytecode fcmpl, so unordered returns -1. 1186 if( tf1->is_nan() || tf2->is_nan() ) 1187 return TypeInt::CC_LT; 1188 1189 if( tf1->_f < tf2->_f ) return TypeInt::CC_LT; 1190 if( tf1->_f > tf2->_f ) return TypeInt::CC_GT; 1191 assert( tf1->_f == tf2->_f, "do not understand FP behavior" ); 1192 return TypeInt::CC_EQ; 1193 } 1194 1195 1196 //============================================================================= 1197 //------------------------------Value------------------------------------------ 1198 // Simplify an CmpD (compare 2 doubles ) node, based on local information. 1199 // If both inputs are constants, compare them. 1200 const Type* CmpDNode::Value(PhaseGVN* phase) const { 1201 const Node* in1 = in(1); 1202 const Node* in2 = in(2); 1203 // Either input is TOP ==> the result is TOP 1204 const Type* t1 = (in1 == this) ? Type::TOP : phase->type(in1); 1205 if( t1 == Type::TOP ) return Type::TOP; 1206 const Type* t2 = (in2 == this) ? Type::TOP : phase->type(in2); 1207 if( t2 == Type::TOP ) return Type::TOP; 1208 1209 // Not constants? Don't know squat - even if they are the same 1210 // value! If they are NaN's they compare to LT instead of EQ. 1211 const TypeD *td1 = t1->isa_double_constant(); 1212 const TypeD *td2 = t2->isa_double_constant(); 1213 if( !td1 || !td2 ) return TypeInt::CC; 1214 1215 // This implements the Java bytecode dcmpl, so unordered returns -1. 1216 if( td1->is_nan() || td2->is_nan() ) 1217 return TypeInt::CC_LT; 1218 1219 if( td1->_d < td2->_d ) return TypeInt::CC_LT; 1220 if( td1->_d > td2->_d ) return TypeInt::CC_GT; 1221 assert( td1->_d == td2->_d, "do not understand FP behavior" ); 1222 return TypeInt::CC_EQ; 1223 } 1224 1225 //------------------------------Ideal------------------------------------------ 1226 Node *CmpDNode::Ideal(PhaseGVN *phase, bool can_reshape){ 1227 // Check if we can change this to a CmpF and remove a ConvD2F operation. 1228 // Change (CMPD (F2D (float)) (ConD value)) 1229 // To (CMPF (float) (ConF value)) 1230 // Valid when 'value' does not lose precision as a float. 1231 // Benefits: eliminates conversion, does not require 24-bit mode 1232 1233 // NaNs prevent commuting operands. This transform works regardless of the 1234 // order of ConD and ConvF2D inputs by preserving the original order. 1235 int idx_f2d = 1; // ConvF2D on left side? 1236 if( in(idx_f2d)->Opcode() != Op_ConvF2D ) 1237 idx_f2d = 2; // No, swap to check for reversed args 1238 int idx_con = 3-idx_f2d; // Check for the constant on other input 1239 1240 if( ConvertCmpD2CmpF && 1241 in(idx_f2d)->Opcode() == Op_ConvF2D && 1242 in(idx_con)->Opcode() == Op_ConD ) { 1243 const TypeD *t2 = in(idx_con)->bottom_type()->is_double_constant(); 1244 double t2_value_as_double = t2->_d; 1245 float t2_value_as_float = (float)t2_value_as_double; 1246 if( t2_value_as_double == (double)t2_value_as_float ) { 1247 // Test value can be represented as a float 1248 // Eliminate the conversion to double and create new comparison 1249 Node *new_in1 = in(idx_f2d)->in(1); 1250 Node *new_in2 = phase->makecon( TypeF::make(t2_value_as_float) ); 1251 if( idx_f2d != 1 ) { // Must flip args to match original order 1252 Node *tmp = new_in1; 1253 new_in1 = new_in2; 1254 new_in2 = tmp; 1255 } 1256 CmpFNode *new_cmp = (Opcode() == Op_CmpD3) 1257 ? new CmpF3Node( new_in1, new_in2 ) 1258 : new CmpFNode ( new_in1, new_in2 ) ; 1259 return new_cmp; // Changed to CmpFNode 1260 } 1261 // Testing value required the precision of a double 1262 } 1263 return NULL; // No change 1264 } 1265 1266 1267 //============================================================================= 1268 //------------------------------cc2logical------------------------------------- 1269 // Convert a condition code type to a logical type 1270 const Type *BoolTest::cc2logical( const Type *CC ) const { 1271 if( CC == Type::TOP ) return Type::TOP; 1272 if( CC->base() != Type::Int ) return TypeInt::BOOL; // Bottom or worse 1273 const TypeInt *ti = CC->is_int(); 1274 if( ti->is_con() ) { // Only 1 kind of condition codes set? 1275 // Match low order 2 bits 1276 int tmp = ((ti->get_con()&3) == (_test&3)) ? 1 : 0; 1277 if( _test & 4 ) tmp = 1-tmp; // Optionally complement result 1278 return TypeInt::make(tmp); // Boolean result 1279 } 1280 1281 if( CC == TypeInt::CC_GE ) { 1282 if( _test == ge ) return TypeInt::ONE; 1283 if( _test == lt ) return TypeInt::ZERO; 1284 } 1285 if( CC == TypeInt::CC_LE ) { 1286 if( _test == le ) return TypeInt::ONE; 1287 if( _test == gt ) return TypeInt::ZERO; 1288 } 1289 1290 return TypeInt::BOOL; 1291 } 1292 1293 //------------------------------dump_spec------------------------------------- 1294 // Print special per-node info 1295 void BoolTest::dump_on(outputStream *st) const { 1296 const char *msg[] = {"eq","gt","of","lt","ne","le","nof","ge"}; 1297 st->print("%s", msg[_test]); 1298 } 1299 1300 // Returns the logical AND of two tests (or 'never' if both tests can never be true). 1301 // For example, a test for 'le' followed by a test for 'lt' is equivalent with 'lt'. 1302 BoolTest::mask BoolTest::merge(BoolTest other) const { 1303 const mask res[illegal+1][illegal+1] = { 1304 // eq, gt, of, lt, ne, le, nof, ge, never, illegal 1305 {eq, never, illegal, never, never, eq, illegal, eq, never, illegal}, // eq 1306 {never, gt, illegal, never, gt, never, illegal, gt, never, illegal}, // gt 1307 {illegal, illegal, illegal, illegal, illegal, illegal, illegal, illegal, never, illegal}, // of 1308 {never, never, illegal, lt, lt, lt, illegal, never, never, illegal}, // lt 1309 {never, gt, illegal, lt, ne, lt, illegal, gt, never, illegal}, // ne 1310 {eq, never, illegal, lt, lt, le, illegal, eq, never, illegal}, // le 1311 {illegal, illegal, illegal, illegal, illegal, illegal, illegal, illegal, never, illegal}, // nof 1312 {eq, gt, illegal, never, gt, eq, illegal, ge, never, illegal}, // ge 1313 {never, never, never, never, never, never, never, never, never, illegal}, // never 1314 {illegal, illegal, illegal, illegal, illegal, illegal, illegal, illegal, illegal, illegal}}; // illegal 1315 return res[_test][other._test]; 1316 } 1317 1318 //============================================================================= 1319 uint BoolNode::hash() const { return (Node::hash() << 3)|(_test._test+1); } 1320 uint BoolNode::size_of() const { return sizeof(BoolNode); } 1321 1322 //------------------------------operator==------------------------------------- 1323 bool BoolNode::cmp( const Node &n ) const { 1324 const BoolNode *b = (const BoolNode *)&n; // Cast up 1325 return (_test._test == b->_test._test); 1326 } 1327 1328 //-------------------------------make_predicate-------------------------------- 1329 Node* BoolNode::make_predicate(Node* test_value, PhaseGVN* phase) { 1330 if (test_value->is_Con()) return test_value; 1331 if (test_value->is_Bool()) return test_value; 1332 if (test_value->is_CMove() && 1333 test_value->in(CMoveNode::Condition)->is_Bool()) { 1334 BoolNode* bol = test_value->in(CMoveNode::Condition)->as_Bool(); 1335 const Type* ftype = phase->type(test_value->in(CMoveNode::IfFalse)); 1336 const Type* ttype = phase->type(test_value->in(CMoveNode::IfTrue)); 1337 if (ftype == TypeInt::ZERO && !TypeInt::ZERO->higher_equal(ttype)) { 1338 return bol; 1339 } else if (ttype == TypeInt::ZERO && !TypeInt::ZERO->higher_equal(ftype)) { 1340 return phase->transform( bol->negate(phase) ); 1341 } 1342 // Else fall through. The CMove gets in the way of the test. 1343 // It should be the case that make_predicate(bol->as_int_value()) == bol. 1344 } 1345 Node* cmp = new CmpINode(test_value, phase->intcon(0)); 1346 cmp = phase->transform(cmp); 1347 Node* bol = new BoolNode(cmp, BoolTest::ne); 1348 return phase->transform(bol); 1349 } 1350 1351 //--------------------------------as_int_value--------------------------------- 1352 Node* BoolNode::as_int_value(PhaseGVN* phase) { 1353 // Inverse to make_predicate. The CMove probably boils down to a Conv2B. 1354 Node* cmov = CMoveNode::make(NULL, this, 1355 phase->intcon(0), phase->intcon(1), 1356 TypeInt::BOOL); 1357 return phase->transform(cmov); 1358 } 1359 1360 //----------------------------------negate------------------------------------- 1361 BoolNode* BoolNode::negate(PhaseGVN* phase) { 1362 return new BoolNode(in(1), _test.negate()); 1363 } 1364 1365 // Change "bool eq/ne (cmp (add/sub A B) C)" into false/true if add/sub 1366 // overflows and we can prove that C is not in the two resulting ranges. 1367 // This optimization is similar to the one performed by CmpUNode::Value(). 1368 Node* BoolNode::fold_cmpI(PhaseGVN* phase, SubNode* cmp, Node* cmp1, int cmp_op, 1369 int cmp1_op, const TypeInt* cmp2_type) { 1370 // Only optimize eq/ne integer comparison of add/sub 1371 if((_test._test == BoolTest::eq || _test._test == BoolTest::ne) && 1372 (cmp_op == Op_CmpI) && (cmp1_op == Op_AddI || cmp1_op == Op_SubI)) { 1373 // Skip cases were inputs of add/sub are not integers or of bottom type 1374 const TypeInt* r0 = phase->type(cmp1->in(1))->isa_int(); 1375 const TypeInt* r1 = phase->type(cmp1->in(2))->isa_int(); 1376 if ((r0 != NULL) && (r0 != TypeInt::INT) && 1377 (r1 != NULL) && (r1 != TypeInt::INT) && 1378 (cmp2_type != TypeInt::INT)) { 1379 // Compute exact (long) type range of add/sub result 1380 jlong lo_long = r0->_lo; 1381 jlong hi_long = r0->_hi; 1382 if (cmp1_op == Op_AddI) { 1383 lo_long += r1->_lo; 1384 hi_long += r1->_hi; 1385 } else { 1386 lo_long -= r1->_hi; 1387 hi_long -= r1->_lo; 1388 } 1389 // Check for over-/underflow by casting to integer 1390 int lo_int = (int)lo_long; 1391 int hi_int = (int)hi_long; 1392 bool underflow = lo_long != (jlong)lo_int; 1393 bool overflow = hi_long != (jlong)hi_int; 1394 if ((underflow != overflow) && (hi_int < lo_int)) { 1395 // Overflow on one boundary, compute resulting type ranges: 1396 // tr1 [MIN_INT, hi_int] and tr2 [lo_int, MAX_INT] 1397 int w = MAX2(r0->_widen, r1->_widen); // _widen does not matter here 1398 const TypeInt* tr1 = TypeInt::make(min_jint, hi_int, w); 1399 const TypeInt* tr2 = TypeInt::make(lo_int, max_jint, w); 1400 // Compare second input of cmp to both type ranges 1401 const Type* sub_tr1 = cmp->sub(tr1, cmp2_type); 1402 const Type* sub_tr2 = cmp->sub(tr2, cmp2_type); 1403 if (sub_tr1 == TypeInt::CC_LT && sub_tr2 == TypeInt::CC_GT) { 1404 // The result of the add/sub will never equal cmp2. Replace BoolNode 1405 // by false (0) if it tests for equality and by true (1) otherwise. 1406 return ConINode::make((_test._test == BoolTest::eq) ? 0 : 1); 1407 } 1408 } 1409 } 1410 } 1411 return NULL; 1412 } 1413 1414 static bool is_counted_loop_cmp(Node *cmp) { 1415 Node *n = cmp->in(1)->in(1); 1416 return n != NULL && 1417 n->is_Phi() && 1418 n->in(0) != NULL && 1419 n->in(0)->is_CountedLoop() && 1420 n->in(0)->as_CountedLoop()->phi() == n; 1421 } 1422 1423 //------------------------------Ideal------------------------------------------ 1424 Node *BoolNode::Ideal(PhaseGVN *phase, bool can_reshape) { 1425 // Change "bool tst (cmp con x)" into "bool ~tst (cmp x con)". 1426 // This moves the constant to the right. Helps value-numbering. 1427 Node *cmp = in(1); 1428 if( !cmp->is_Sub() ) return NULL; 1429 int cop = cmp->Opcode(); 1430 if( cop == Op_FastLock || cop == Op_FastUnlock || cmp->is_SubTypeCheck()) return NULL; 1431 Node *cmp1 = cmp->in(1); 1432 Node *cmp2 = cmp->in(2); 1433 if( !cmp1 ) return NULL; 1434 1435 if (_test._test == BoolTest::overflow || _test._test == BoolTest::no_overflow) { 1436 return NULL; 1437 } 1438 1439 const int cmp1_op = cmp1->Opcode(); 1440 const int cmp2_op = cmp2->Opcode(); 1441 1442 // Constant on left? 1443 Node *con = cmp1; 1444 // Move constants to the right of compare's to canonicalize. 1445 // Do not muck with Opaque1 nodes, as this indicates a loop 1446 // guard that cannot change shape. 1447 if (con->is_Con() && !cmp2->is_Con() && cmp2_op != Op_OpaqueZeroTripGuard && 1448 // Because of NaN's, CmpD and CmpF are not commutative 1449 cop != Op_CmpD && cop != Op_CmpF && 1450 // Protect against swapping inputs to a compare when it is used by a 1451 // counted loop exit, which requires maintaining the loop-limit as in(2) 1452 !is_counted_loop_exit_test() ) { 1453 // Ok, commute the constant to the right of the cmp node. 1454 // Clone the Node, getting a new Node of the same class 1455 cmp = cmp->clone(); 1456 // Swap inputs to the clone 1457 cmp->swap_edges(1, 2); 1458 cmp = phase->transform( cmp ); 1459 return new BoolNode( cmp, _test.commute() ); 1460 } 1461 1462 // Change "bool eq/ne (cmp (and X 16) 16)" into "bool ne/eq (cmp (and X 16) 0)". 1463 if (cop == Op_CmpI && 1464 (_test._test == BoolTest::eq || _test._test == BoolTest::ne) && 1465 cmp1_op == Op_AndI && cmp2_op == Op_ConI && 1466 cmp1->in(2)->Opcode() == Op_ConI) { 1467 const TypeInt *t12 = phase->type(cmp2)->isa_int(); 1468 const TypeInt *t112 = phase->type(cmp1->in(2))->isa_int(); 1469 if (t12 && t12->is_con() && t112 && t112->is_con() && 1470 t12->get_con() == t112->get_con() && is_power_of_2(t12->get_con())) { 1471 Node *ncmp = phase->transform(new CmpINode(cmp1, phase->intcon(0))); 1472 return new BoolNode(ncmp, _test.negate()); 1473 } 1474 } 1475 1476 // Same for long type: change "bool eq/ne (cmp (and X 16) 16)" into "bool ne/eq (cmp (and X 16) 0)". 1477 if (cop == Op_CmpL && 1478 (_test._test == BoolTest::eq || _test._test == BoolTest::ne) && 1479 cmp1_op == Op_AndL && cmp2_op == Op_ConL && 1480 cmp1->in(2)->Opcode() == Op_ConL) { 1481 const TypeLong *t12 = phase->type(cmp2)->isa_long(); 1482 const TypeLong *t112 = phase->type(cmp1->in(2))->isa_long(); 1483 if (t12 && t12->is_con() && t112 && t112->is_con() && 1484 t12->get_con() == t112->get_con() && is_power_of_2(t12->get_con())) { 1485 Node *ncmp = phase->transform(new CmpLNode(cmp1, phase->longcon(0))); 1486 return new BoolNode(ncmp, _test.negate()); 1487 } 1488 } 1489 1490 // Change "cmp (add X min_jint) (add Y min_jint)" into "cmpu X Y" 1491 // and "cmp (add X min_jint) c" into "cmpu X (c + min_jint)" 1492 if (cop == Op_CmpI && 1493 cmp1_op == Op_AddI && 1494 phase->type(cmp1->in(2)) == TypeInt::MIN) { 1495 if (cmp2_op == Op_ConI) { 1496 Node* ncmp2 = phase->intcon(java_add(cmp2->get_int(), min_jint)); 1497 Node* ncmp = phase->transform(new CmpUNode(cmp1->in(1), ncmp2)); 1498 return new BoolNode(ncmp, _test._test); 1499 } else if (cmp2_op == Op_AddI && 1500 phase->type(cmp2->in(2)) == TypeInt::MIN) { 1501 Node* ncmp = phase->transform(new CmpUNode(cmp1->in(1), cmp2->in(1))); 1502 return new BoolNode(ncmp, _test._test); 1503 } 1504 } 1505 1506 // Change "cmp (add X min_jlong) (add Y min_jlong)" into "cmpu X Y" 1507 // and "cmp (add X min_jlong) c" into "cmpu X (c + min_jlong)" 1508 if (cop == Op_CmpL && 1509 cmp1_op == Op_AddL && 1510 phase->type(cmp1->in(2)) == TypeLong::MIN) { 1511 if (cmp2_op == Op_ConL) { 1512 Node* ncmp2 = phase->longcon(java_add(cmp2->get_long(), min_jlong)); 1513 Node* ncmp = phase->transform(new CmpULNode(cmp1->in(1), ncmp2)); 1514 return new BoolNode(ncmp, _test._test); 1515 } else if (cmp2_op == Op_AddL && 1516 phase->type(cmp2->in(2)) == TypeLong::MIN) { 1517 Node* ncmp = phase->transform(new CmpULNode(cmp1->in(1), cmp2->in(1))); 1518 return new BoolNode(ncmp, _test._test); 1519 } 1520 } 1521 1522 // Change "bool eq/ne (cmp (xor X 1) 0)" into "bool ne/eq (cmp X 0)". 1523 // The XOR-1 is an idiom used to flip the sense of a bool. We flip the 1524 // test instead. 1525 const TypeInt* cmp2_type = phase->type(cmp2)->isa_int(); 1526 if (cmp2_type == NULL) return NULL; 1527 Node* j_xor = cmp1; 1528 if( cmp2_type == TypeInt::ZERO && 1529 cmp1_op == Op_XorI && 1530 j_xor->in(1) != j_xor && // An xor of itself is dead 1531 phase->type( j_xor->in(1) ) == TypeInt::BOOL && 1532 phase->type( j_xor->in(2) ) == TypeInt::ONE && 1533 (_test._test == BoolTest::eq || 1534 _test._test == BoolTest::ne) ) { 1535 Node *ncmp = phase->transform(new CmpINode(j_xor->in(1),cmp2)); 1536 return new BoolNode( ncmp, _test.negate() ); 1537 } 1538 1539 // Change ((x & m) u<= m) or ((m & x) u<= m) to always true 1540 // Same with ((x & m) u< m+1) and ((m & x) u< m+1) 1541 if (cop == Op_CmpU && 1542 cmp1_op == Op_AndI) { 1543 Node* bound = NULL; 1544 if (_test._test == BoolTest::le) { 1545 bound = cmp2; 1546 } else if (_test._test == BoolTest::lt && 1547 cmp2->Opcode() == Op_AddI && 1548 cmp2->in(2)->find_int_con(0) == 1) { 1549 bound = cmp2->in(1); 1550 } 1551 if (cmp1->in(2) == bound || cmp1->in(1) == bound) { 1552 return ConINode::make(1); 1553 } 1554 } 1555 1556 // Change ((x & (m - 1)) u< m) into (m > 0) 1557 // This is the off-by-one variant of the above 1558 if (cop == Op_CmpU && 1559 _test._test == BoolTest::lt && 1560 cmp1_op == Op_AndI) { 1561 Node* l = cmp1->in(1); 1562 Node* r = cmp1->in(2); 1563 for (int repeat = 0; repeat < 2; repeat++) { 1564 bool match = r->Opcode() == Op_AddI && r->in(2)->find_int_con(0) == -1 && 1565 r->in(1) == cmp2; 1566 if (match) { 1567 // arraylength known to be non-negative, so a (arraylength != 0) is sufficient, 1568 // but to be compatible with the array range check pattern, use (arraylength u> 0) 1569 Node* ncmp = cmp2->Opcode() == Op_LoadRange 1570 ? phase->transform(new CmpUNode(cmp2, phase->intcon(0))) 1571 : phase->transform(new CmpINode(cmp2, phase->intcon(0))); 1572 return new BoolNode(ncmp, BoolTest::gt); 1573 } else { 1574 // commute and try again 1575 l = cmp1->in(2); 1576 r = cmp1->in(1); 1577 } 1578 } 1579 } 1580 1581 // Change x u< 1 or x u<= 0 to x == 0 1582 // and x u> 0 or u>= 1 to x != 0 1583 if (cop == Op_CmpU && 1584 cmp1_op != Op_LoadRange && 1585 (((_test._test == BoolTest::lt || _test._test == BoolTest::ge) && 1586 cmp2->find_int_con(-1) == 1) || 1587 ((_test._test == BoolTest::le || _test._test == BoolTest::gt) && 1588 cmp2->find_int_con(-1) == 0))) { 1589 Node* ncmp = phase->transform(new CmpINode(cmp1, phase->intcon(0))); 1590 return new BoolNode(ncmp, _test.is_less() ? BoolTest::eq : BoolTest::ne); 1591 } 1592 1593 // Change (arraylength <= 0) or (arraylength == 0) 1594 // into (arraylength u<= 0) 1595 // Also change (arraylength != 0) into (arraylength u> 0) 1596 // The latter version matches the code pattern generated for 1597 // array range checks, which will more likely be optimized later. 1598 if (cop == Op_CmpI && 1599 cmp1_op == Op_LoadRange && 1600 cmp2->find_int_con(-1) == 0) { 1601 if (_test._test == BoolTest::le || _test._test == BoolTest::eq) { 1602 Node* ncmp = phase->transform(new CmpUNode(cmp1, cmp2)); 1603 return new BoolNode(ncmp, BoolTest::le); 1604 } else if (_test._test == BoolTest::ne) { 1605 Node* ncmp = phase->transform(new CmpUNode(cmp1, cmp2)); 1606 return new BoolNode(ncmp, BoolTest::gt); 1607 } 1608 } 1609 1610 // Change "bool eq/ne (cmp (Conv2B X) 0)" into "bool eq/ne (cmp X 0)". 1611 // This is a standard idiom for branching on a boolean value. 1612 Node *c2b = cmp1; 1613 if( cmp2_type == TypeInt::ZERO && 1614 cmp1_op == Op_Conv2B && 1615 (_test._test == BoolTest::eq || 1616 _test._test == BoolTest::ne) ) { 1617 Node *ncmp = phase->transform(phase->type(c2b->in(1))->isa_int() 1618 ? (Node*)new CmpINode(c2b->in(1),cmp2) 1619 : (Node*)new CmpPNode(c2b->in(1),phase->makecon(TypePtr::NULL_PTR)) 1620 ); 1621 return new BoolNode( ncmp, _test._test ); 1622 } 1623 1624 // Comparing a SubI against a zero is equal to comparing the SubI 1625 // arguments directly. This only works for eq and ne comparisons 1626 // due to possible integer overflow. 1627 if ((_test._test == BoolTest::eq || _test._test == BoolTest::ne) && 1628 (cop == Op_CmpI) && 1629 (cmp1_op == Op_SubI) && 1630 ( cmp2_type == TypeInt::ZERO ) ) { 1631 Node *ncmp = phase->transform( new CmpINode(cmp1->in(1),cmp1->in(2))); 1632 return new BoolNode( ncmp, _test._test ); 1633 } 1634 1635 // Same as above but with and AddI of a constant 1636 if ((_test._test == BoolTest::eq || _test._test == BoolTest::ne) && 1637 cop == Op_CmpI && 1638 cmp1_op == Op_AddI && 1639 cmp1->in(2) != NULL && 1640 phase->type(cmp1->in(2))->isa_int() && 1641 phase->type(cmp1->in(2))->is_int()->is_con() && 1642 cmp2_type == TypeInt::ZERO && 1643 !is_counted_loop_cmp(cmp) // modifying the exit test of a counted loop messes the counted loop shape 1644 ) { 1645 const TypeInt* cmp1_in2 = phase->type(cmp1->in(2))->is_int(); 1646 Node *ncmp = phase->transform( new CmpINode(cmp1->in(1),phase->intcon(-cmp1_in2->_hi))); 1647 return new BoolNode( ncmp, _test._test ); 1648 } 1649 1650 // Change "bool eq/ne (cmp (phi (X -X) 0))" into "bool eq/ne (cmp X 0)" 1651 // since zero check of conditional negation of an integer is equal to 1652 // zero check of the integer directly. 1653 if ((_test._test == BoolTest::eq || _test._test == BoolTest::ne) && 1654 (cop == Op_CmpI) && 1655 (cmp2_type == TypeInt::ZERO) && 1656 (cmp1_op == Op_Phi)) { 1657 // There should be a diamond phi with true path at index 1 or 2 1658 PhiNode *phi = cmp1->as_Phi(); 1659 int idx_true = phi->is_diamond_phi(); 1660 if (idx_true != 0) { 1661 // True input is in(idx_true) while false input is in(3 - idx_true) 1662 Node *tin = phi->in(idx_true); 1663 Node *fin = phi->in(3 - idx_true); 1664 if ((tin->Opcode() == Op_SubI) && 1665 (phase->type(tin->in(1)) == TypeInt::ZERO) && 1666 (tin->in(2) == fin)) { 1667 // Found conditional negation at true path, create a new CmpINode without that 1668 Node *ncmp = phase->transform(new CmpINode(fin, cmp2)); 1669 return new BoolNode(ncmp, _test._test); 1670 } 1671 if ((fin->Opcode() == Op_SubI) && 1672 (phase->type(fin->in(1)) == TypeInt::ZERO) && 1673 (fin->in(2) == tin)) { 1674 // Found conditional negation at false path, create a new CmpINode without that 1675 Node *ncmp = phase->transform(new CmpINode(tin, cmp2)); 1676 return new BoolNode(ncmp, _test._test); 1677 } 1678 } 1679 } 1680 1681 // Change (-A vs 0) into (A vs 0) by commuting the test. Disallow in the 1682 // most general case because negating 0x80000000 does nothing. Needed for 1683 // the CmpF3/SubI/CmpI idiom. 1684 if( cop == Op_CmpI && 1685 cmp1_op == Op_SubI && 1686 cmp2_type == TypeInt::ZERO && 1687 phase->type( cmp1->in(1) ) == TypeInt::ZERO && 1688 phase->type( cmp1->in(2) )->higher_equal(TypeInt::SYMINT) ) { 1689 Node *ncmp = phase->transform( new CmpINode(cmp1->in(2),cmp2)); 1690 return new BoolNode( ncmp, _test.commute() ); 1691 } 1692 1693 // Try to optimize signed integer comparison 1694 return fold_cmpI(phase, cmp->as_Sub(), cmp1, cop, cmp1_op, cmp2_type); 1695 1696 // The transformation below is not valid for either signed or unsigned 1697 // comparisons due to wraparound concerns at MAX_VALUE and MIN_VALUE. 1698 // This transformation can be resurrected when we are able to 1699 // make inferences about the range of values being subtracted from 1700 // (or added to) relative to the wraparound point. 1701 // 1702 // // Remove +/-1's if possible. 1703 // // "X <= Y-1" becomes "X < Y" 1704 // // "X+1 <= Y" becomes "X < Y" 1705 // // "X < Y+1" becomes "X <= Y" 1706 // // "X-1 < Y" becomes "X <= Y" 1707 // // Do not this to compares off of the counted-loop-end. These guys are 1708 // // checking the trip counter and they want to use the post-incremented 1709 // // counter. If they use the PRE-incremented counter, then the counter has 1710 // // to be incremented in a private block on a loop backedge. 1711 // if( du && du->cnt(this) && du->out(this)[0]->Opcode() == Op_CountedLoopEnd ) 1712 // return NULL; 1713 // #ifndef PRODUCT 1714 // // Do not do this in a wash GVN pass during verification. 1715 // // Gets triggered by too many simple optimizations to be bothered with 1716 // // re-trying it again and again. 1717 // if( !phase->allow_progress() ) return NULL; 1718 // #endif 1719 // // Not valid for unsigned compare because of corner cases in involving zero. 1720 // // For example, replacing "X-1 <u Y" with "X <=u Y" fails to throw an 1721 // // exception in case X is 0 (because 0-1 turns into 4billion unsigned but 1722 // // "0 <=u Y" is always true). 1723 // if( cmp->Opcode() == Op_CmpU ) return NULL; 1724 // int cmp2_op = cmp2->Opcode(); 1725 // if( _test._test == BoolTest::le ) { 1726 // if( cmp1_op == Op_AddI && 1727 // phase->type( cmp1->in(2) ) == TypeInt::ONE ) 1728 // return clone_cmp( cmp, cmp1->in(1), cmp2, phase, BoolTest::lt ); 1729 // else if( cmp2_op == Op_AddI && 1730 // phase->type( cmp2->in(2) ) == TypeInt::MINUS_1 ) 1731 // return clone_cmp( cmp, cmp1, cmp2->in(1), phase, BoolTest::lt ); 1732 // } else if( _test._test == BoolTest::lt ) { 1733 // if( cmp1_op == Op_AddI && 1734 // phase->type( cmp1->in(2) ) == TypeInt::MINUS_1 ) 1735 // return clone_cmp( cmp, cmp1->in(1), cmp2, phase, BoolTest::le ); 1736 // else if( cmp2_op == Op_AddI && 1737 // phase->type( cmp2->in(2) ) == TypeInt::ONE ) 1738 // return clone_cmp( cmp, cmp1, cmp2->in(1), phase, BoolTest::le ); 1739 // } 1740 } 1741 1742 //------------------------------Value------------------------------------------ 1743 // Simplify a Bool (convert condition codes to boolean (1 or 0)) node, 1744 // based on local information. If the input is constant, do it. 1745 const Type* BoolNode::Value(PhaseGVN* phase) const { 1746 return _test.cc2logical( phase->type( in(1) ) ); 1747 } 1748 1749 #ifndef PRODUCT 1750 //------------------------------dump_spec-------------------------------------- 1751 // Dump special per-node info 1752 void BoolNode::dump_spec(outputStream *st) const { 1753 st->print("["); 1754 _test.dump_on(st); 1755 st->print("]"); 1756 } 1757 #endif 1758 1759 //----------------------is_counted_loop_exit_test------------------------------ 1760 // Returns true if node is used by a counted loop node. 1761 bool BoolNode::is_counted_loop_exit_test() { 1762 for( DUIterator_Fast imax, i = fast_outs(imax); i < imax; i++ ) { 1763 Node* use = fast_out(i); 1764 if (use->is_CountedLoopEnd()) { 1765 return true; 1766 } 1767 } 1768 return false; 1769 } 1770 1771 //============================================================================= 1772 //------------------------------Value------------------------------------------ 1773 const Type* AbsNode::Value(PhaseGVN* phase) const { 1774 const Type* t1 = phase->type(in(1)); 1775 if (t1 == Type::TOP) return Type::TOP; 1776 1777 switch (t1->base()) { 1778 case Type::Int: { 1779 const TypeInt* ti = t1->is_int(); 1780 if (ti->is_con()) { 1781 return TypeInt::make(uabs(ti->get_con())); 1782 } 1783 break; 1784 } 1785 case Type::Long: { 1786 const TypeLong* tl = t1->is_long(); 1787 if (tl->is_con()) { 1788 return TypeLong::make(uabs(tl->get_con())); 1789 } 1790 break; 1791 } 1792 case Type::FloatCon: 1793 return TypeF::make(abs(t1->getf())); 1794 case Type::DoubleCon: 1795 return TypeD::make(abs(t1->getd())); 1796 default: 1797 break; 1798 } 1799 1800 return bottom_type(); 1801 } 1802 1803 //------------------------------Identity---------------------------------------- 1804 Node* AbsNode::Identity(PhaseGVN* phase) { 1805 Node* in1 = in(1); 1806 // No need to do abs for non-negative values 1807 if (phase->type(in1)->higher_equal(TypeInt::POS) || 1808 phase->type(in1)->higher_equal(TypeLong::POS)) { 1809 return in1; 1810 } 1811 // Convert "abs(abs(x))" into "abs(x)" 1812 if (in1->Opcode() == Opcode()) { 1813 return in1; 1814 } 1815 return this; 1816 } 1817 1818 //------------------------------Ideal------------------------------------------ 1819 Node* AbsNode::Ideal(PhaseGVN* phase, bool can_reshape) { 1820 Node* in1 = in(1); 1821 // Convert "abs(0-x)" into "abs(x)" 1822 if (in1->is_Sub() && phase->type(in1->in(1))->is_zero_type()) { 1823 set_req_X(1, in1->in(2), phase); 1824 return this; 1825 } 1826 return NULL; 1827 } 1828 1829 //============================================================================= 1830 //------------------------------Value------------------------------------------ 1831 // Compute sqrt 1832 const Type* SqrtDNode::Value(PhaseGVN* phase) const { 1833 const Type *t1 = phase->type( in(1) ); 1834 if( t1 == Type::TOP ) return Type::TOP; 1835 if( t1->base() != Type::DoubleCon ) return Type::DOUBLE; 1836 double d = t1->getd(); 1837 if( d < 0.0 ) return Type::DOUBLE; 1838 return TypeD::make( sqrt( d ) ); 1839 } 1840 1841 const Type* SqrtFNode::Value(PhaseGVN* phase) const { 1842 const Type *t1 = phase->type( in(1) ); 1843 if( t1 == Type::TOP ) return Type::TOP; 1844 if( t1->base() != Type::FloatCon ) return Type::FLOAT; 1845 float f = t1->getf(); 1846 if( f < 0.0f ) return Type::FLOAT; 1847 return TypeF::make( (float)sqrt( (double)f ) ); 1848 } 1849 1850 const Type* ReverseINode::Value(PhaseGVN* phase) const { 1851 const Type *t1 = phase->type( in(1) ); 1852 if (t1 == Type::TOP) { 1853 return Type::TOP; 1854 } 1855 const TypeInt* t1int = t1->isa_int(); 1856 if (t1int && t1int->is_con()) { 1857 jint res = reverse_bits(t1int->get_con()); 1858 return TypeInt::make(res); 1859 } 1860 return bottom_type(); 1861 } 1862 1863 const Type* ReverseLNode::Value(PhaseGVN* phase) const { 1864 const Type *t1 = phase->type( in(1) ); 1865 if (t1 == Type::TOP) { 1866 return Type::TOP; 1867 } 1868 const TypeLong* t1long = t1->isa_long(); 1869 if (t1long && t1long->is_con()) { 1870 jlong res = reverse_bits(t1long->get_con()); 1871 return TypeLong::make(res); 1872 } 1873 return bottom_type(); 1874 } 1875 1876 Node* ReverseINode::Identity(PhaseGVN* phase) { 1877 if (in(1)->Opcode() == Op_ReverseI) { 1878 return in(1)->in(1); 1879 } 1880 return this; 1881 } 1882 1883 Node* ReverseLNode::Identity(PhaseGVN* phase) { 1884 if (in(1)->Opcode() == Op_ReverseL) { 1885 return in(1)->in(1); 1886 } 1887 return this; 1888 }