1 /*
   2  * Copyright (c) 1997, 2022, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  *
  23  */
  24 
  25 #include "precompiled.hpp"
  26 #include "compiler/compileLog.hpp"
  27 #include "gc/shared/barrierSet.hpp"
  28 #include "gc/shared/c2/barrierSetC2.hpp"
  29 #include "memory/allocation.inline.hpp"
  30 #include "opto/addnode.hpp"
  31 #include "opto/callnode.hpp"
  32 #include "opto/cfgnode.hpp"
  33 #include "opto/inlinetypenode.hpp"
  34 #include "opto/loopnode.hpp"
  35 #include "opto/matcher.hpp"
  36 #include "opto/movenode.hpp"
  37 #include "opto/mulnode.hpp"
  38 #include "opto/opcodes.hpp"
  39 #include "opto/phaseX.hpp"
  40 #include "opto/subnode.hpp"
  41 #include "runtime/sharedRuntime.hpp"
  42 
  43 // Portions of code courtesy of Clifford Click
  44 
  45 // Optimization - Graph Style
  46 
  47 #include "math.h"
  48 
  49 //=============================================================================
  50 //------------------------------Identity---------------------------------------
  51 // If right input is a constant 0, return the left input.
  52 Node* SubNode::Identity(PhaseGVN* phase) {
  53   assert(in(1) != this, "Must already have called Value");
  54   assert(in(2) != this, "Must already have called Value");
  55 
  56   // Remove double negation
  57   const Type *zero = add_id();
  58   if( phase->type( in(1) )->higher_equal( zero ) &&
  59       in(2)->Opcode() == Opcode() &&
  60       phase->type( in(2)->in(1) )->higher_equal( zero ) ) {
  61     return in(2)->in(2);
  62   }
  63 
  64   // Convert "(X+Y) - Y" into X and "(X+Y) - X" into Y
  65   if (in(1)->Opcode() == Op_AddI || in(1)->Opcode() == Op_AddL) {
  66     if (in(1)->in(2) == in(2)) {
  67       return in(1)->in(1);
  68     }
  69     if (in(1)->in(1) == in(2)) {
  70       return in(1)->in(2);
  71     }
  72 
  73     // Also catch: "(X + Opaque2(Y)) - Y".  In this case, 'Y' is a loop-varying
  74     // trip counter and X is likely to be loop-invariant (that's how O2 Nodes
  75     // are originally used, although the optimizer sometimes jiggers things).
  76     // This folding through an O2 removes a loop-exit use of a loop-varying
  77     // value and generally lowers register pressure in and around the loop.
  78     if (in(1)->in(2)->Opcode() == Op_Opaque2 && in(1)->in(2)->in(1) == in(2)) {
  79       return in(1)->in(1);
  80     }
  81   }
  82 
  83   return ( phase->type( in(2) )->higher_equal( zero ) ) ? in(1) : this;
  84 }
  85 
  86 //------------------------------Value------------------------------------------
  87 // A subtract node differences it's two inputs.
  88 const Type* SubNode::Value_common(PhaseTransform *phase) const {
  89   const Node* in1 = in(1);
  90   const Node* in2 = in(2);
  91   // Either input is TOP ==> the result is TOP
  92   const Type* t1 = (in1 == this) ? Type::TOP : phase->type(in1);
  93   if( t1 == Type::TOP ) return Type::TOP;
  94   const Type* t2 = (in2 == this) ? Type::TOP : phase->type(in2);
  95   if( t2 == Type::TOP ) return Type::TOP;
  96 
  97   // Not correct for SubFnode and AddFNode (must check for infinity)
  98   // Equal?  Subtract is zero
  99   if (in1->eqv_uncast(in2))  return add_id();
 100 
 101   // Either input is BOTTOM ==> the result is the local BOTTOM
 102   if( t1 == Type::BOTTOM || t2 == Type::BOTTOM )
 103     return bottom_type();
 104 
 105   return NULL;
 106 }
 107 
 108 const Type* SubNode::Value(PhaseGVN* phase) const {
 109   const Type* t = Value_common(phase);
 110   if (t != NULL) {
 111     return t;
 112   }
 113   const Type* t1 = phase->type(in(1));
 114   const Type* t2 = phase->type(in(2));
 115   return sub(t1,t2);            // Local flavor of type subtraction
 116 
 117 }
 118 
 119 SubNode* SubNode::make(Node* in1, Node* in2, BasicType bt) {
 120   switch (bt) {
 121     case T_INT:
 122       return new SubINode(in1, in2);
 123     case T_LONG:
 124       return new SubLNode(in1, in2);
 125     default:
 126       fatal("Not implemented for %s", type2name(bt));
 127   }
 128   return NULL;
 129 }
 130 
 131 //=============================================================================
 132 //------------------------------Helper function--------------------------------
 133 
 134 static bool is_cloop_increment(Node* inc) {
 135   precond(inc->Opcode() == Op_AddI || inc->Opcode() == Op_AddL);
 136 
 137   if (!inc->in(1)->is_Phi()) {
 138     return false;
 139   }
 140   const PhiNode* phi = inc->in(1)->as_Phi();
 141 
 142   if (!phi->region()->is_CountedLoop()) {
 143     return false;
 144   }
 145 
 146   return inc == phi->region()->as_CountedLoop()->incr();
 147 }
 148 
 149 // Given the expression '(x + C) - v', or
 150 //                      'v - (x + C)', we examine nodes '+' and 'v':
 151 //
 152 //  1. Do not convert if '+' is a counted-loop increment, because the '-' is
 153 //     loop invariant and converting extends the live-range of 'x' to overlap
 154 //     with the '+', forcing another register to be used in the loop.
 155 //
 156 //  2. Do not convert if 'v' is a counted-loop induction variable, because
 157 //     'x' might be invariant.
 158 //
 159 static bool ok_to_convert(Node* inc, Node* var) {
 160   return !(is_cloop_increment(inc) || var->is_cloop_ind_var());
 161 }
 162 
 163 //------------------------------Ideal------------------------------------------
 164 Node *SubINode::Ideal(PhaseGVN *phase, bool can_reshape){
 165   Node *in1 = in(1);
 166   Node *in2 = in(2);
 167   uint op1 = in1->Opcode();
 168   uint op2 = in2->Opcode();
 169 
 170 #ifdef ASSERT
 171   // Check for dead loop
 172   if ((in1 == this) || (in2 == this) ||
 173       ((op1 == Op_AddI || op1 == Op_SubI) &&
 174        ((in1->in(1) == this) || (in1->in(2) == this) ||
 175         (in1->in(1) == in1)  || (in1->in(2) == in1)))) {
 176     assert(false, "dead loop in SubINode::Ideal");
 177   }
 178 #endif
 179 
 180   const Type *t2 = phase->type( in2 );
 181   if( t2 == Type::TOP ) return NULL;
 182   // Convert "x-c0" into "x+ -c0".
 183   if( t2->base() == Type::Int ){        // Might be bottom or top...
 184     const TypeInt *i = t2->is_int();
 185     if( i->is_con() )
 186       return new AddINode(in1, phase->intcon(-i->get_con()));
 187   }
 188 
 189   // Convert "(x+c0) - y" into (x-y) + c0"
 190   // Do not collapse (x+c0)-y if "+" is a loop increment or
 191   // if "y" is a loop induction variable.
 192   if( op1 == Op_AddI && ok_to_convert(in1, in2) ) {
 193     const Type *tadd = phase->type( in1->in(2) );
 194     if( tadd->singleton() && tadd != Type::TOP ) {
 195       Node *sub2 = phase->transform( new SubINode( in1->in(1), in2 ));
 196       return new AddINode( sub2, in1->in(2) );
 197     }
 198   }
 199 
 200   // Convert "x - (y+c0)" into "(x-y) - c0" AND
 201   // Convert "c1 - (y+c0)" into "(c1-c0) - y"
 202   // Need the same check as in above optimization but reversed.
 203   if (op2 == Op_AddI
 204       && ok_to_convert(in2, in1)
 205       && in2->in(2)->Opcode() == Op_ConI) {
 206     jint c0 = phase->type(in2->in(2))->isa_int()->get_con();
 207     Node* in21 = in2->in(1);
 208     if (in1->Opcode() == Op_ConI) {
 209       // Match c1
 210       jint c1 = phase->type(in1)->isa_int()->get_con();
 211       Node* sub2 = phase->intcon(java_subtract(c1, c0));
 212       return new SubINode(sub2, in21);
 213     } else {
 214       // Match x
 215       Node* sub2 = phase->transform(new SubINode(in1, in21));
 216       Node* neg_c0 = phase->intcon(-c0);
 217       return new AddINode(sub2, neg_c0);
 218     }
 219   }
 220 
 221   const Type *t1 = phase->type( in1 );
 222   if( t1 == Type::TOP ) return NULL;
 223 
 224 #ifdef ASSERT
 225   // Check for dead loop
 226   if ((op2 == Op_AddI || op2 == Op_SubI) &&
 227       ((in2->in(1) == this) || (in2->in(2) == this) ||
 228        (in2->in(1) == in2)  || (in2->in(2) == in2))) {
 229     assert(false, "dead loop in SubINode::Ideal");
 230   }
 231 #endif
 232 
 233   // Convert "x - (x+y)" into "-y"
 234   if (op2 == Op_AddI && in1 == in2->in(1)) {
 235     return new SubINode(phase->intcon(0), in2->in(2));
 236   }
 237   // Convert "(x-y) - x" into "-y"
 238   if (op1 == Op_SubI && in1->in(1) == in2) {
 239     return new SubINode(phase->intcon(0), in1->in(2));
 240   }
 241   // Convert "x - (y+x)" into "-y"
 242   if (op2 == Op_AddI && in1 == in2->in(2)) {
 243     return new SubINode(phase->intcon(0), in2->in(1));
 244   }
 245 
 246   // Convert "0 - (x-y)" into "y-x", leave the double negation "-(-y)" to SubNode::Identity().
 247   if (t1 == TypeInt::ZERO && op2 == Op_SubI && phase->type(in2->in(1)) != TypeInt::ZERO) {
 248     return new SubINode(in2->in(2), in2->in(1));
 249   }
 250 
 251   // Convert "0 - (x+con)" into "-con-x"
 252   jint con;
 253   if( t1 == TypeInt::ZERO && op2 == Op_AddI &&
 254       (con = in2->in(2)->find_int_con(0)) != 0 )
 255     return new SubINode( phase->intcon(-con), in2->in(1) );
 256 
 257   // Convert "(X+A) - (X+B)" into "A - B"
 258   if( op1 == Op_AddI && op2 == Op_AddI && in1->in(1) == in2->in(1) )
 259     return new SubINode( in1->in(2), in2->in(2) );
 260 
 261   // Convert "(A+X) - (B+X)" into "A - B"
 262   if( op1 == Op_AddI && op2 == Op_AddI && in1->in(2) == in2->in(2) )
 263     return new SubINode( in1->in(1), in2->in(1) );
 264 
 265   // Convert "(A+X) - (X+B)" into "A - B"
 266   if( op1 == Op_AddI && op2 == Op_AddI && in1->in(2) == in2->in(1) )
 267     return new SubINode( in1->in(1), in2->in(2) );
 268 
 269   // Convert "(X+A) - (B+X)" into "A - B"
 270   if( op1 == Op_AddI && op2 == Op_AddI && in1->in(1) == in2->in(2) )
 271     return new SubINode( in1->in(2), in2->in(1) );
 272 
 273   // Convert "A-(B-C)" into (A+C)-B", since add is commutative and generally
 274   // nicer to optimize than subtract.
 275   if( op2 == Op_SubI && in2->outcnt() == 1) {
 276     Node *add1 = phase->transform( new AddINode( in1, in2->in(2) ) );
 277     return new SubINode( add1, in2->in(1) );
 278   }
 279 
 280   // Associative
 281   if (op1 == Op_MulI && op2 == Op_MulI) {
 282     Node* sub_in1 = NULL;
 283     Node* sub_in2 = NULL;
 284     Node* mul_in = NULL;
 285 
 286     if (in1->in(1) == in2->in(1)) {
 287       // Convert "a*b-a*c into a*(b-c)
 288       sub_in1 = in1->in(2);
 289       sub_in2 = in2->in(2);
 290       mul_in = in1->in(1);
 291     } else if (in1->in(2) == in2->in(1)) {
 292       // Convert a*b-b*c into b*(a-c)
 293       sub_in1 = in1->in(1);
 294       sub_in2 = in2->in(2);
 295       mul_in = in1->in(2);
 296     } else if (in1->in(2) == in2->in(2)) {
 297       // Convert a*c-b*c into (a-b)*c
 298       sub_in1 = in1->in(1);
 299       sub_in2 = in2->in(1);
 300       mul_in = in1->in(2);
 301     } else if (in1->in(1) == in2->in(2)) {
 302       // Convert a*b-c*a into a*(b-c)
 303       sub_in1 = in1->in(2);
 304       sub_in2 = in2->in(1);
 305       mul_in = in1->in(1);
 306     }
 307 
 308     if (mul_in != NULL) {
 309       Node* sub = phase->transform(new SubINode(sub_in1, sub_in2));
 310       return new MulINode(mul_in, sub);
 311     }
 312   }
 313 
 314   // Convert "0-(A>>31)" into "(A>>>31)"
 315   if ( op2 == Op_RShiftI ) {
 316     Node *in21 = in2->in(1);
 317     Node *in22 = in2->in(2);
 318     const TypeInt *zero = phase->type(in1)->isa_int();
 319     const TypeInt *t21 = phase->type(in21)->isa_int();
 320     const TypeInt *t22 = phase->type(in22)->isa_int();
 321     if ( t21 && t22 && zero == TypeInt::ZERO && t22->is_con(31) ) {
 322       return new URShiftINode(in21, in22);
 323     }
 324   }
 325 
 326   return NULL;
 327 }
 328 
 329 //------------------------------sub--------------------------------------------
 330 // A subtract node differences it's two inputs.
 331 const Type *SubINode::sub( const Type *t1, const Type *t2 ) const {
 332   const TypeInt *r0 = t1->is_int(); // Handy access
 333   const TypeInt *r1 = t2->is_int();
 334   int32_t lo = java_subtract(r0->_lo, r1->_hi);
 335   int32_t hi = java_subtract(r0->_hi, r1->_lo);
 336 
 337   // We next check for 32-bit overflow.
 338   // If that happens, we just assume all integers are possible.
 339   if( (((r0->_lo ^ r1->_hi) >= 0) ||    // lo ends have same signs OR
 340        ((r0->_lo ^      lo) >= 0)) &&   // lo results have same signs AND
 341       (((r0->_hi ^ r1->_lo) >= 0) ||    // hi ends have same signs OR
 342        ((r0->_hi ^      hi) >= 0)) )    // hi results have same signs
 343     return TypeInt::make(lo,hi,MAX2(r0->_widen,r1->_widen));
 344   else                          // Overflow; assume all integers
 345     return TypeInt::INT;
 346 }
 347 
 348 //=============================================================================
 349 //------------------------------Ideal------------------------------------------
 350 Node *SubLNode::Ideal(PhaseGVN *phase, bool can_reshape) {
 351   Node *in1 = in(1);
 352   Node *in2 = in(2);
 353   uint op1 = in1->Opcode();
 354   uint op2 = in2->Opcode();
 355 
 356 #ifdef ASSERT
 357   // Check for dead loop
 358   if ((in1 == this) || (in2 == this) ||
 359       ((op1 == Op_AddL || op1 == Op_SubL) &&
 360        ((in1->in(1) == this) || (in1->in(2) == this) ||
 361         (in1->in(1) == in1)  || (in1->in(2) == in1)))) {
 362     assert(false, "dead loop in SubLNode::Ideal");
 363   }
 364 #endif
 365 
 366   if( phase->type( in2 ) == Type::TOP ) return NULL;
 367   const TypeLong *i = phase->type( in2 )->isa_long();
 368   // Convert "x-c0" into "x+ -c0".
 369   if( i &&                      // Might be bottom or top...
 370       i->is_con() )
 371     return new AddLNode(in1, phase->longcon(-i->get_con()));
 372 
 373   // Convert "(x+c0) - y" into (x-y) + c0"
 374   // Do not collapse (x+c0)-y if "+" is a loop increment or
 375   // if "y" is a loop induction variable.
 376   if( op1 == Op_AddL && ok_to_convert(in1, in2) ) {
 377     Node *in11 = in1->in(1);
 378     const Type *tadd = phase->type( in1->in(2) );
 379     if( tadd->singleton() && tadd != Type::TOP ) {
 380       Node *sub2 = phase->transform( new SubLNode( in11, in2 ));
 381       return new AddLNode( sub2, in1->in(2) );
 382     }
 383   }
 384 
 385   // Convert "x - (y+c0)" into "(x-y) - c0" AND
 386   // Convert "c1 - (y+c0)" into "(c1-c0) - y"
 387   // Need the same check as in above optimization but reversed.
 388   if (op2 == Op_AddL
 389       && ok_to_convert(in2, in1)
 390       && in2->in(2)->Opcode() == Op_ConL) {
 391     jlong c0 = phase->type(in2->in(2))->isa_long()->get_con();
 392     Node* in21 = in2->in(1);
 393     if (in1->Opcode() == Op_ConL) {
 394       // Match c1
 395       jlong c1 = phase->type(in1)->isa_long()->get_con();
 396       Node* sub2 = phase->longcon(java_subtract(c1, c0));
 397       return new SubLNode(sub2, in21);
 398     } else {
 399       Node* sub2 = phase->transform(new SubLNode(in1, in21));
 400       Node* neg_c0 = phase->longcon(-c0);
 401       return new AddLNode(sub2, neg_c0);
 402     }
 403   }
 404 
 405   const Type *t1 = phase->type( in1 );
 406   if( t1 == Type::TOP ) return NULL;
 407 
 408 #ifdef ASSERT
 409   // Check for dead loop
 410   if ((op2 == Op_AddL || op2 == Op_SubL) &&
 411       ((in2->in(1) == this) || (in2->in(2) == this) ||
 412        (in2->in(1) == in2)  || (in2->in(2) == in2))) {
 413     assert(false, "dead loop in SubLNode::Ideal");
 414   }
 415 #endif
 416 
 417   // Convert "x - (x+y)" into "-y"
 418   if (op2 == Op_AddL && in1 == in2->in(1)) {
 419     return new SubLNode(phase->makecon(TypeLong::ZERO), in2->in(2));
 420   }
 421   // Convert "(x-y) - x" into "-y"
 422   if (op1 == Op_SubL && in1->in(1) == in2) {
 423     return new SubLNode(phase->makecon(TypeLong::ZERO), in1->in(2));
 424   }
 425   // Convert "x - (y+x)" into "-y"
 426   if (op2 == Op_AddL && in1 == in2->in(2)) {
 427     return new SubLNode(phase->makecon(TypeLong::ZERO), in2->in(1));
 428   }
 429 
 430   // Convert "0 - (x-y)" into "y-x", leave the double negation "-(-y)" to SubNode::Identity.
 431   if (t1 == TypeLong::ZERO && op2 == Op_SubL && phase->type(in2->in(1)) != TypeLong::ZERO) {
 432     return new SubLNode(in2->in(2), in2->in(1));
 433   }
 434 
 435   // Convert "(X+A) - (X+B)" into "A - B"
 436   if( op1 == Op_AddL && op2 == Op_AddL && in1->in(1) == in2->in(1) )
 437     return new SubLNode( in1->in(2), in2->in(2) );
 438 
 439   // Convert "(A+X) - (B+X)" into "A - B"
 440   if( op1 == Op_AddL && op2 == Op_AddL && in1->in(2) == in2->in(2) )
 441     return new SubLNode( in1->in(1), in2->in(1) );
 442 
 443   // Convert "(A+X) - (X+B)" into "A - B"
 444   if( op1 == Op_AddL && op2 == Op_AddL && in1->in(2) == in2->in(1) )
 445     return new SubLNode( in1->in(1), in2->in(2) );
 446 
 447   // Convert "(X+A) - (B+X)" into "A - B"
 448   if( op1 == Op_AddL && op2 == Op_AddL && in1->in(1) == in2->in(2) )
 449     return new SubLNode( in1->in(2), in2->in(1) );
 450 
 451   // Convert "A-(B-C)" into (A+C)-B"
 452   if( op2 == Op_SubL && in2->outcnt() == 1) {
 453     Node *add1 = phase->transform( new AddLNode( in1, in2->in(2) ) );
 454     return new SubLNode( add1, in2->in(1) );
 455   }
 456 
 457   // Associative
 458   if (op1 == Op_MulL && op2 == Op_MulL) {
 459     Node* sub_in1 = NULL;
 460     Node* sub_in2 = NULL;
 461     Node* mul_in = NULL;
 462 
 463     if (in1->in(1) == in2->in(1)) {
 464       // Convert "a*b-a*c into a*(b+c)
 465       sub_in1 = in1->in(2);
 466       sub_in2 = in2->in(2);
 467       mul_in = in1->in(1);
 468     } else if (in1->in(2) == in2->in(1)) {
 469       // Convert a*b-b*c into b*(a-c)
 470       sub_in1 = in1->in(1);
 471       sub_in2 = in2->in(2);
 472       mul_in = in1->in(2);
 473     } else if (in1->in(2) == in2->in(2)) {
 474       // Convert a*c-b*c into (a-b)*c
 475       sub_in1 = in1->in(1);
 476       sub_in2 = in2->in(1);
 477       mul_in = in1->in(2);
 478     } else if (in1->in(1) == in2->in(2)) {
 479       // Convert a*b-c*a into a*(b-c)
 480       sub_in1 = in1->in(2);
 481       sub_in2 = in2->in(1);
 482       mul_in = in1->in(1);
 483     }
 484 
 485     if (mul_in != NULL) {
 486       Node* sub = phase->transform(new SubLNode(sub_in1, sub_in2));
 487       return new MulLNode(mul_in, sub);
 488     }
 489   }
 490 
 491   // Convert "0L-(A>>63)" into "(A>>>63)"
 492   if ( op2 == Op_RShiftL ) {
 493     Node *in21 = in2->in(1);
 494     Node *in22 = in2->in(2);
 495     const TypeLong *zero = phase->type(in1)->isa_long();
 496     const TypeLong *t21 = phase->type(in21)->isa_long();
 497     const TypeInt *t22 = phase->type(in22)->isa_int();
 498     if ( t21 && t22 && zero == TypeLong::ZERO && t22->is_con(63) ) {
 499       return new URShiftLNode(in21, in22);
 500     }
 501   }
 502 
 503   return NULL;
 504 }
 505 
 506 //------------------------------sub--------------------------------------------
 507 // A subtract node differences it's two inputs.
 508 const Type *SubLNode::sub( const Type *t1, const Type *t2 ) const {
 509   const TypeLong *r0 = t1->is_long(); // Handy access
 510   const TypeLong *r1 = t2->is_long();
 511   jlong lo = java_subtract(r0->_lo, r1->_hi);
 512   jlong hi = java_subtract(r0->_hi, r1->_lo);
 513 
 514   // We next check for 32-bit overflow.
 515   // If that happens, we just assume all integers are possible.
 516   if( (((r0->_lo ^ r1->_hi) >= 0) ||    // lo ends have same signs OR
 517        ((r0->_lo ^      lo) >= 0)) &&   // lo results have same signs AND
 518       (((r0->_hi ^ r1->_lo) >= 0) ||    // hi ends have same signs OR
 519        ((r0->_hi ^      hi) >= 0)) )    // hi results have same signs
 520     return TypeLong::make(lo,hi,MAX2(r0->_widen,r1->_widen));
 521   else                          // Overflow; assume all integers
 522     return TypeLong::LONG;
 523 }
 524 
 525 //=============================================================================
 526 //------------------------------Value------------------------------------------
 527 // A subtract node differences its two inputs.
 528 const Type* SubFPNode::Value(PhaseGVN* phase) const {
 529   const Node* in1 = in(1);
 530   const Node* in2 = in(2);
 531   // Either input is TOP ==> the result is TOP
 532   const Type* t1 = (in1 == this) ? Type::TOP : phase->type(in1);
 533   if( t1 == Type::TOP ) return Type::TOP;
 534   const Type* t2 = (in2 == this) ? Type::TOP : phase->type(in2);
 535   if( t2 == Type::TOP ) return Type::TOP;
 536 
 537   // if both operands are infinity of same sign, the result is NaN; do
 538   // not replace with zero
 539   if (t1->is_finite() && t2->is_finite() && in1 == in2) {
 540     return add_id();
 541   }
 542 
 543   // Either input is BOTTOM ==> the result is the local BOTTOM
 544   const Type *bot = bottom_type();
 545   if( (t1 == bot) || (t2 == bot) ||
 546       (t1 == Type::BOTTOM) || (t2 == Type::BOTTOM) )
 547     return bot;
 548 
 549   return sub(t1,t2);            // Local flavor of type subtraction
 550 }
 551 
 552 
 553 //=============================================================================
 554 //------------------------------Ideal------------------------------------------
 555 Node *SubFNode::Ideal(PhaseGVN *phase, bool can_reshape) {
 556   const Type *t2 = phase->type( in(2) );
 557   // Convert "x-c0" into "x+ -c0".
 558   if( t2->base() == Type::FloatCon ) {  // Might be bottom or top...
 559     // return new (phase->C, 3) AddFNode(in(1), phase->makecon( TypeF::make(-t2->getf()) ) );
 560   }
 561 
 562   // Cannot replace 0.0-X with -X because a 'fsub' bytecode computes
 563   // 0.0-0.0 as +0.0, while a 'fneg' bytecode computes -0.0.
 564   //if( phase->type(in(1)) == TypeF::ZERO )
 565   //return new (phase->C, 2) NegFNode(in(2));
 566 
 567   return NULL;
 568 }
 569 
 570 //------------------------------sub--------------------------------------------
 571 // A subtract node differences its two inputs.
 572 const Type *SubFNode::sub( const Type *t1, const Type *t2 ) const {
 573   // no folding if one of operands is infinity or NaN, do not do constant folding
 574   if( g_isfinite(t1->getf()) && g_isfinite(t2->getf()) ) {
 575     return TypeF::make( t1->getf() - t2->getf() );
 576   }
 577   else if( g_isnan(t1->getf()) ) {
 578     return t1;
 579   }
 580   else if( g_isnan(t2->getf()) ) {
 581     return t2;
 582   }
 583   else {
 584     return Type::FLOAT;
 585   }
 586 }
 587 
 588 //=============================================================================
 589 //------------------------------Ideal------------------------------------------
 590 Node *SubDNode::Ideal(PhaseGVN *phase, bool can_reshape){
 591   const Type *t2 = phase->type( in(2) );
 592   // Convert "x-c0" into "x+ -c0".
 593   if( t2->base() == Type::DoubleCon ) { // Might be bottom or top...
 594     // return new (phase->C, 3) AddDNode(in(1), phase->makecon( TypeD::make(-t2->getd()) ) );
 595   }
 596 
 597   // Cannot replace 0.0-X with -X because a 'dsub' bytecode computes
 598   // 0.0-0.0 as +0.0, while a 'dneg' bytecode computes -0.0.
 599   //if( phase->type(in(1)) == TypeD::ZERO )
 600   //return new (phase->C, 2) NegDNode(in(2));
 601 
 602   return NULL;
 603 }
 604 
 605 //------------------------------sub--------------------------------------------
 606 // A subtract node differences its two inputs.
 607 const Type *SubDNode::sub( const Type *t1, const Type *t2 ) const {
 608   // no folding if one of operands is infinity or NaN, do not do constant folding
 609   if( g_isfinite(t1->getd()) && g_isfinite(t2->getd()) ) {
 610     return TypeD::make( t1->getd() - t2->getd() );
 611   }
 612   else if( g_isnan(t1->getd()) ) {
 613     return t1;
 614   }
 615   else if( g_isnan(t2->getd()) ) {
 616     return t2;
 617   }
 618   else {
 619     return Type::DOUBLE;
 620   }
 621 }
 622 
 623 //=============================================================================
 624 //------------------------------Idealize---------------------------------------
 625 // Unlike SubNodes, compare must still flatten return value to the
 626 // range -1, 0, 1.
 627 // And optimizations like those for (X + Y) - X fail if overflow happens.
 628 Node* CmpNode::Identity(PhaseGVN* phase) {
 629   return this;
 630 }
 631 
 632 #ifndef PRODUCT
 633 //----------------------------related------------------------------------------
 634 // Related nodes of comparison nodes include all data inputs (until hitting a
 635 // control boundary) as well as all outputs until and including control nodes
 636 // as well as their projections. In compact mode, data inputs till depth 1 and
 637 // all outputs till depth 1 are considered.
 638 void CmpNode::related(GrowableArray<Node*> *in_rel, GrowableArray<Node*> *out_rel, bool compact) const {
 639   if (compact) {
 640     this->collect_nodes(in_rel, 1, false, true);
 641     this->collect_nodes(out_rel, -1, false, false);
 642   } else {
 643     this->collect_nodes_in_all_data(in_rel, false);
 644     this->collect_nodes_out_all_ctrl_boundary(out_rel);
 645     // Now, find all control nodes in out_rel, and include their projections
 646     // and projection targets (if any) in the result.
 647     GrowableArray<Node*> proj(Compile::current()->unique());
 648     for (GrowableArrayIterator<Node*> it = out_rel->begin(); it != out_rel->end(); ++it) {
 649       Node* n = *it;
 650       if (n->is_CFG() && !n->is_Proj()) {
 651         // Assume projections and projection targets are found at levels 1 and 2.
 652         n->collect_nodes(&proj, -2, false, false);
 653         for (GrowableArrayIterator<Node*> p = proj.begin(); p != proj.end(); ++p) {
 654           out_rel->append_if_missing(*p);
 655         }
 656         proj.clear();
 657       }
 658     }
 659   }
 660 }
 661 
 662 #endif
 663 
 664 CmpNode *CmpNode::make(Node *in1, Node *in2, BasicType bt, bool unsigned_comp) {
 665   switch (bt) {
 666     case T_INT:
 667       if (unsigned_comp) {
 668         return new CmpUNode(in1, in2);
 669       }
 670       return new CmpINode(in1, in2);
 671     case T_LONG:
 672       if (unsigned_comp) {
 673         return new CmpULNode(in1, in2);
 674       }
 675       return new CmpLNode(in1, in2);
 676     default:
 677       fatal("Not implemented for %s", type2name(bt));
 678   }
 679   return NULL;
 680 }
 681 
 682 //=============================================================================
 683 //------------------------------cmp--------------------------------------------
 684 // Simplify a CmpI (compare 2 integers) node, based on local information.
 685 // If both inputs are constants, compare them.
 686 const Type *CmpINode::sub( const Type *t1, const Type *t2 ) const {
 687   const TypeInt *r0 = t1->is_int(); // Handy access
 688   const TypeInt *r1 = t2->is_int();
 689 
 690   if( r0->_hi < r1->_lo )       // Range is always low?
 691     return TypeInt::CC_LT;
 692   else if( r0->_lo > r1->_hi )  // Range is always high?
 693     return TypeInt::CC_GT;
 694 
 695   else if( r0->is_con() && r1->is_con() ) { // comparing constants?
 696     assert(r0->get_con() == r1->get_con(), "must be equal");
 697     return TypeInt::CC_EQ;      // Equal results.
 698   } else if( r0->_hi == r1->_lo ) // Range is never high?
 699     return TypeInt::CC_LE;
 700   else if( r0->_lo == r1->_hi ) // Range is never low?
 701     return TypeInt::CC_GE;
 702   return TypeInt::CC;           // else use worst case results
 703 }
 704 
 705 // Simplify a CmpU (compare 2 integers) node, based on local information.
 706 // If both inputs are constants, compare them.
 707 const Type *CmpUNode::sub( const Type *t1, const Type *t2 ) const {
 708   assert(!t1->isa_ptr(), "obsolete usage of CmpU");
 709 
 710   // comparing two unsigned ints
 711   const TypeInt *r0 = t1->is_int();   // Handy access
 712   const TypeInt *r1 = t2->is_int();
 713 
 714   // Current installed version
 715   // Compare ranges for non-overlap
 716   juint lo0 = r0->_lo;
 717   juint hi0 = r0->_hi;
 718   juint lo1 = r1->_lo;
 719   juint hi1 = r1->_hi;
 720 
 721   // If either one has both negative and positive values,
 722   // it therefore contains both 0 and -1, and since [0..-1] is the
 723   // full unsigned range, the type must act as an unsigned bottom.
 724   bool bot0 = ((jint)(lo0 ^ hi0) < 0);
 725   bool bot1 = ((jint)(lo1 ^ hi1) < 0);
 726 
 727   if (bot0 || bot1) {
 728     // All unsigned values are LE -1 and GE 0.
 729     if (lo0 == 0 && hi0 == 0) {
 730       return TypeInt::CC_LE;            //   0 <= bot
 731     } else if ((jint)lo0 == -1 && (jint)hi0 == -1) {
 732       return TypeInt::CC_GE;            // -1 >= bot
 733     } else if (lo1 == 0 && hi1 == 0) {
 734       return TypeInt::CC_GE;            // bot >= 0
 735     } else if ((jint)lo1 == -1 && (jint)hi1 == -1) {
 736       return TypeInt::CC_LE;            // bot <= -1
 737     }
 738   } else {
 739     // We can use ranges of the form [lo..hi] if signs are the same.
 740     assert(lo0 <= hi0 && lo1 <= hi1, "unsigned ranges are valid");
 741     // results are reversed, '-' > '+' for unsigned compare
 742     if (hi0 < lo1) {
 743       return TypeInt::CC_LT;            // smaller
 744     } else if (lo0 > hi1) {
 745       return TypeInt::CC_GT;            // greater
 746     } else if (hi0 == lo1 && lo0 == hi1) {
 747       return TypeInt::CC_EQ;            // Equal results
 748     } else if (lo0 >= hi1) {
 749       return TypeInt::CC_GE;
 750     } else if (hi0 <= lo1) {
 751       // Check for special case in Hashtable::get.  (See below.)
 752       if ((jint)lo0 >= 0 && (jint)lo1 >= 0 && is_index_range_check())
 753         return TypeInt::CC_LT;
 754       return TypeInt::CC_LE;
 755     }
 756   }
 757   // Check for special case in Hashtable::get - the hash index is
 758   // mod'ed to the table size so the following range check is useless.
 759   // Check for: (X Mod Y) CmpU Y, where the mod result and Y both have
 760   // to be positive.
 761   // (This is a gross hack, since the sub method never
 762   // looks at the structure of the node in any other case.)
 763   if ((jint)lo0 >= 0 && (jint)lo1 >= 0 && is_index_range_check())
 764     return TypeInt::CC_LT;
 765   return TypeInt::CC;                   // else use worst case results
 766 }
 767 
 768 const Type* CmpUNode::Value(PhaseGVN* phase) const {
 769   const Type* t = SubNode::Value_common(phase);
 770   if (t != NULL) {
 771     return t;
 772   }
 773   const Node* in1 = in(1);
 774   const Node* in2 = in(2);
 775   const Type* t1 = phase->type(in1);
 776   const Type* t2 = phase->type(in2);
 777   assert(t1->isa_int(), "CmpU has only Int type inputs");
 778   if (t2 == TypeInt::INT) { // Compare to bottom?
 779     return bottom_type();
 780   }
 781   uint in1_op = in1->Opcode();
 782   if (in1_op == Op_AddI || in1_op == Op_SubI) {
 783     // The problem rise when result of AddI(SubI) may overflow
 784     // signed integer value. Let say the input type is
 785     // [256, maxint] then +128 will create 2 ranges due to
 786     // overflow: [minint, minint+127] and [384, maxint].
 787     // But C2 type system keep only 1 type range and as result
 788     // it use general [minint, maxint] for this case which we
 789     // can't optimize.
 790     //
 791     // Make 2 separate type ranges based on types of AddI(SubI) inputs
 792     // and compare results of their compare. If results are the same
 793     // CmpU node can be optimized.
 794     const Node* in11 = in1->in(1);
 795     const Node* in12 = in1->in(2);
 796     const Type* t11 = (in11 == in1) ? Type::TOP : phase->type(in11);
 797     const Type* t12 = (in12 == in1) ? Type::TOP : phase->type(in12);
 798     // Skip cases when input types are top or bottom.
 799     if ((t11 != Type::TOP) && (t11 != TypeInt::INT) &&
 800         (t12 != Type::TOP) && (t12 != TypeInt::INT)) {
 801       const TypeInt *r0 = t11->is_int();
 802       const TypeInt *r1 = t12->is_int();
 803       jlong lo_r0 = r0->_lo;
 804       jlong hi_r0 = r0->_hi;
 805       jlong lo_r1 = r1->_lo;
 806       jlong hi_r1 = r1->_hi;
 807       if (in1_op == Op_SubI) {
 808         jlong tmp = hi_r1;
 809         hi_r1 = -lo_r1;
 810         lo_r1 = -tmp;
 811         // Note, for substructing [minint,x] type range
 812         // long arithmetic provides correct overflow answer.
 813         // The confusion come from the fact that in 32-bit
 814         // -minint == minint but in 64-bit -minint == maxint+1.
 815       }
 816       jlong lo_long = lo_r0 + lo_r1;
 817       jlong hi_long = hi_r0 + hi_r1;
 818       int lo_tr1 = min_jint;
 819       int hi_tr1 = (int)hi_long;
 820       int lo_tr2 = (int)lo_long;
 821       int hi_tr2 = max_jint;
 822       bool underflow = lo_long != (jlong)lo_tr2;
 823       bool overflow  = hi_long != (jlong)hi_tr1;
 824       // Use sub(t1, t2) when there is no overflow (one type range)
 825       // or when both overflow and underflow (too complex).
 826       if ((underflow != overflow) && (hi_tr1 < lo_tr2)) {
 827         // Overflow only on one boundary, compare 2 separate type ranges.
 828         int w = MAX2(r0->_widen, r1->_widen); // _widen does not matter here
 829         const TypeInt* tr1 = TypeInt::make(lo_tr1, hi_tr1, w);
 830         const TypeInt* tr2 = TypeInt::make(lo_tr2, hi_tr2, w);
 831         const Type* cmp1 = sub(tr1, t2);
 832         const Type* cmp2 = sub(tr2, t2);
 833         if (cmp1 == cmp2) {
 834           return cmp1; // Hit!
 835         }
 836       }
 837     }
 838   }
 839 
 840   return sub(t1, t2);            // Local flavor of type subtraction
 841 }
 842 
 843 bool CmpUNode::is_index_range_check() const {
 844   // Check for the "(X ModI Y) CmpU Y" shape
 845   return (in(1)->Opcode() == Op_ModI &&
 846           in(1)->in(2)->eqv_uncast(in(2)));
 847 }
 848 
 849 //------------------------------Idealize---------------------------------------
 850 Node *CmpINode::Ideal( PhaseGVN *phase, bool can_reshape ) {
 851   if (phase->type(in(2))->higher_equal(TypeInt::ZERO)) {
 852     switch (in(1)->Opcode()) {
 853     case Op_CmpL3:              // Collapse a CmpL3/CmpI into a CmpL
 854       return new CmpLNode(in(1)->in(1),in(1)->in(2));
 855     case Op_CmpF3:              // Collapse a CmpF3/CmpI into a CmpF
 856       return new CmpFNode(in(1)->in(1),in(1)->in(2));
 857     case Op_CmpD3:              // Collapse a CmpD3/CmpI into a CmpD
 858       return new CmpDNode(in(1)->in(1),in(1)->in(2));
 859     //case Op_SubI:
 860       // If (x - y) cannot overflow, then ((x - y) <?> 0)
 861       // can be turned into (x <?> y).
 862       // This is handled (with more general cases) by Ideal_sub_algebra.
 863     }
 864   }
 865   return NULL;                  // No change
 866 }
 867 
 868 //------------------------------Ideal------------------------------------------
 869 Node* CmpLNode::Ideal(PhaseGVN* phase, bool can_reshape) {
 870   Node* a = NULL;
 871   Node* b = NULL;
 872   if (is_double_null_check(phase, a, b) && (phase->type(a)->is_zero_type() || phase->type(b)->is_zero_type())) {
 873     // Degraded to a simple null check, use old acmp
 874     return new CmpPNode(a, b);
 875   }
 876   const TypeLong *t2 = phase->type(in(2))->isa_long();
 877   if (Opcode() == Op_CmpL && in(1)->Opcode() == Op_ConvI2L && t2 && t2->is_con()) {
 878     const jlong con = t2->get_con();
 879     if (con >= min_jint && con <= max_jint) {
 880       return new CmpINode(in(1)->in(1), phase->intcon((jint)con));
 881     }
 882   }
 883   return NULL;
 884 }
 885 
 886 // Match double null check emitted by Compile::optimize_acmp()
 887 bool CmpLNode::is_double_null_check(PhaseGVN* phase, Node*& a, Node*& b) const {
 888   if (in(1)->Opcode() == Op_OrL &&
 889       in(1)->in(1)->Opcode() == Op_CastP2X &&
 890       in(1)->in(2)->Opcode() == Op_CastP2X &&
 891       in(2)->bottom_type()->is_zero_type()) {
 892     assert(EnableValhalla, "unexpected double null check");
 893     a = in(1)->in(1)->in(1);
 894     b = in(1)->in(2)->in(1);
 895     return true;
 896   }
 897   return false;
 898 }
 899 
 900 //------------------------------Value------------------------------------------
 901 const Type* CmpLNode::Value(PhaseGVN* phase) const {
 902   Node* a = NULL;
 903   Node* b = NULL;
 904   if (is_double_null_check(phase, a, b) && (!phase->type(a)->maybe_null() || !phase->type(b)->maybe_null())) {
 905     // One operand is never NULL, emit constant false
 906     return TypeInt::CC_GT;
 907   }
 908   return SubNode::Value(phase);
 909 }
 910 
 911 //=============================================================================
 912 // Simplify a CmpL (compare 2 longs ) node, based on local information.
 913 // If both inputs are constants, compare them.
 914 const Type *CmpLNode::sub( const Type *t1, const Type *t2 ) const {
 915   const TypeLong *r0 = t1->is_long(); // Handy access
 916   const TypeLong *r1 = t2->is_long();
 917 
 918   if( r0->_hi < r1->_lo )       // Range is always low?
 919     return TypeInt::CC_LT;
 920   else if( r0->_lo > r1->_hi )  // Range is always high?
 921     return TypeInt::CC_GT;
 922 
 923   else if( r0->is_con() && r1->is_con() ) { // comparing constants?
 924     assert(r0->get_con() == r1->get_con(), "must be equal");
 925     return TypeInt::CC_EQ;      // Equal results.
 926   } else if( r0->_hi == r1->_lo ) // Range is never high?
 927     return TypeInt::CC_LE;
 928   else if( r0->_lo == r1->_hi ) // Range is never low?
 929     return TypeInt::CC_GE;
 930   return TypeInt::CC;           // else use worst case results
 931 }
 932 
 933 
 934 // Simplify a CmpUL (compare 2 unsigned longs) node, based on local information.
 935 // If both inputs are constants, compare them.
 936 const Type* CmpULNode::sub(const Type* t1, const Type* t2) const {
 937   assert(!t1->isa_ptr(), "obsolete usage of CmpUL");
 938 
 939   // comparing two unsigned longs
 940   const TypeLong* r0 = t1->is_long();   // Handy access
 941   const TypeLong* r1 = t2->is_long();
 942 
 943   // Current installed version
 944   // Compare ranges for non-overlap
 945   julong lo0 = r0->_lo;
 946   julong hi0 = r0->_hi;
 947   julong lo1 = r1->_lo;
 948   julong hi1 = r1->_hi;
 949 
 950   // If either one has both negative and positive values,
 951   // it therefore contains both 0 and -1, and since [0..-1] is the
 952   // full unsigned range, the type must act as an unsigned bottom.
 953   bool bot0 = ((jlong)(lo0 ^ hi0) < 0);
 954   bool bot1 = ((jlong)(lo1 ^ hi1) < 0);
 955 
 956   if (bot0 || bot1) {
 957     // All unsigned values are LE -1 and GE 0.
 958     if (lo0 == 0 && hi0 == 0) {
 959       return TypeInt::CC_LE;            //   0 <= bot
 960     } else if ((jlong)lo0 == -1 && (jlong)hi0 == -1) {
 961       return TypeInt::CC_GE;            // -1 >= bot
 962     } else if (lo1 == 0 && hi1 == 0) {
 963       return TypeInt::CC_GE;            // bot >= 0
 964     } else if ((jlong)lo1 == -1 && (jlong)hi1 == -1) {
 965       return TypeInt::CC_LE;            // bot <= -1
 966     }
 967   } else {
 968     // We can use ranges of the form [lo..hi] if signs are the same.
 969     assert(lo0 <= hi0 && lo1 <= hi1, "unsigned ranges are valid");
 970     // results are reversed, '-' > '+' for unsigned compare
 971     if (hi0 < lo1) {
 972       return TypeInt::CC_LT;            // smaller
 973     } else if (lo0 > hi1) {
 974       return TypeInt::CC_GT;            // greater
 975     } else if (hi0 == lo1 && lo0 == hi1) {
 976       return TypeInt::CC_EQ;            // Equal results
 977     } else if (lo0 >= hi1) {
 978       return TypeInt::CC_GE;
 979     } else if (hi0 <= lo1) {
 980       return TypeInt::CC_LE;
 981     }
 982   }
 983 
 984   return TypeInt::CC;                   // else use worst case results
 985 }
 986 
 987 //=============================================================================
 988 //------------------------------sub--------------------------------------------
 989 // Simplify an CmpP (compare 2 pointers) node, based on local information.
 990 // If both inputs are constants, compare them.
 991 const Type *CmpPNode::sub( const Type *t1, const Type *t2 ) const {
 992   const TypePtr *r0 = t1->is_ptr(); // Handy access
 993   const TypePtr *r1 = t2->is_ptr();
 994 
 995   // Undefined inputs makes for an undefined result
 996   if( TypePtr::above_centerline(r0->_ptr) ||
 997       TypePtr::above_centerline(r1->_ptr) )
 998     return Type::TOP;
 999 
1000   if (r0 == r1 && r0->singleton()) {
1001     // Equal pointer constants (klasses, nulls, etc.)
1002     return TypeInt::CC_EQ;
1003   }
1004 
1005   // See if it is 2 unrelated classes.
1006   const TypeOopPtr* oop_p0 = r0->isa_oopptr();
1007   const TypeOopPtr* oop_p1 = r1->isa_oopptr();
1008   bool both_oop_ptr = oop_p0 && oop_p1;
1009 
1010   if (both_oop_ptr) {
1011     Node* in1 = in(1)->uncast();
1012     Node* in2 = in(2)->uncast();
1013     AllocateNode* alloc1 = AllocateNode::Ideal_allocation(in1, NULL);
1014     AllocateNode* alloc2 = AllocateNode::Ideal_allocation(in2, NULL);
1015     if (MemNode::detect_ptr_independence(in1, alloc1, in2, alloc2, NULL)) {
1016       return TypeInt::CC_GT;  // different pointers
1017     }
1018   }
1019 
1020   const TypeKlassPtr* klass_p0 = r0->isa_klassptr();
1021   const TypeKlassPtr* klass_p1 = r1->isa_klassptr();
1022 
1023   if (both_oop_ptr || (klass_p0 && klass_p1)) { // both or neither are klass pointers
1024     ciKlass* klass0 = NULL;
1025     bool    xklass0 = false;
1026     ciKlass* klass1 = NULL;
1027     bool    xklass1 = false;
1028 
1029     if (oop_p0) {
1030       klass0 = oop_p0->klass();
1031       xklass0 = oop_p0->klass_is_exact();
1032     } else {
1033       assert(klass_p0, "must be non-null if oop_p0 is null");
1034       klass0 = klass_p0->klass();
1035       xklass0 = klass_p0->klass_is_exact();
1036     }
1037 
1038     if (oop_p1) {
1039       klass1 = oop_p1->klass();
1040       xklass1 = oop_p1->klass_is_exact();
1041     } else {
1042       assert(klass_p1, "must be non-null if oop_p1 is null");
1043       klass1 = klass_p1->klass();
1044       xklass1 = klass_p1->klass_is_exact();
1045     }
1046 
1047     if (klass0 && klass1 &&
1048         klass0->is_loaded() && !klass0->is_interface() && // do not trust interfaces
1049         klass1->is_loaded() && !klass1->is_interface() &&
1050         (!klass0->is_obj_array_klass() ||
1051          !klass0->as_obj_array_klass()->base_element_klass()->is_interface()) &&
1052         (!klass1->is_obj_array_klass() ||
1053          !klass1->as_obj_array_klass()->base_element_klass()->is_interface())) {
1054       bool unrelated_classes = false;
1055       // See if neither subclasses the other, or if the class on top
1056       // is precise.  In either of these cases, the compare is known
1057       // to fail if at least one of the pointers is provably not null.
1058       if (klass0->equals(klass1)) {  // if types are unequal but klasses are equal
1059         // Do nothing; we know nothing for imprecise types
1060       } else if (klass0->is_subtype_of(klass1)) {
1061         // If klass1's type is PRECISE, then classes are unrelated.
1062         unrelated_classes = xklass1;
1063       } else if (klass1->is_subtype_of(klass0)) {
1064         // If klass0's type is PRECISE, then classes are unrelated.
1065         unrelated_classes = xklass0;
1066       } else {                  // Neither subtypes the other
1067         unrelated_classes = true;
1068       }
1069       if (!unrelated_classes) {
1070         // Handle inline type arrays
1071         if ((r0->flatten_array() && (!r1->can_be_inline_type() || (klass1->is_inlinetype() && !klass1->flatten_array()))) ||
1072             (r1->flatten_array() && (!r0->can_be_inline_type() || (klass0->is_inlinetype() && !klass0->flatten_array())))) {
1073           // One type is flattened in arrays but the other type is not. Must be unrelated.
1074           unrelated_classes = true;
1075         } else if ((r0->is_not_flat() && klass1->is_flat_array_klass()) ||
1076                    (r1->is_not_flat() && klass0->is_flat_array_klass())) {
1077           // One type is a non-flattened array and the other type is a flattened array. Must be unrelated.
1078           unrelated_classes = true;
1079         } else if ((r0->is_not_null_free() && klass1->is_array_klass() && klass1->as_array_klass()->is_elem_null_free()) ||
1080                    (r1->is_not_null_free() && klass0->is_array_klass() && klass0->as_array_klass()->is_elem_null_free())) {
1081           // One type is a non-null-free array and the other type is a null-free array. Must be unrelated.
1082           unrelated_classes = true;
1083         }
1084       }
1085       if (unrelated_classes) {
1086         // The oops classes are known to be unrelated. If the joined PTRs of
1087         // two oops is not Null and not Bottom, then we are sure that one
1088         // of the two oops is non-null, and the comparison will always fail.
1089         TypePtr::PTR jp = r0->join_ptr(r1->_ptr);
1090         if (jp != TypePtr::Null && jp != TypePtr::BotPTR) {
1091           return TypeInt::CC_GT;
1092         }
1093       }
1094     }
1095   }
1096 
1097   // Known constants can be compared exactly
1098   // Null can be distinguished from any NotNull pointers
1099   // Unknown inputs makes an unknown result
1100   if( r0->singleton() ) {
1101     intptr_t bits0 = r0->get_con();
1102     if( r1->singleton() )
1103       return bits0 == r1->get_con() ? TypeInt::CC_EQ : TypeInt::CC_GT;
1104     return ( r1->_ptr == TypePtr::NotNull && bits0==0 ) ? TypeInt::CC_GT : TypeInt::CC;
1105   } else if( r1->singleton() ) {
1106     intptr_t bits1 = r1->get_con();
1107     return ( r0->_ptr == TypePtr::NotNull && bits1==0 ) ? TypeInt::CC_GT : TypeInt::CC;
1108   } else
1109     return TypeInt::CC;
1110 }
1111 
1112 static inline Node* isa_java_mirror_load(PhaseGVN* phase, Node* n) {
1113   // Return the klass node for (indirect load from OopHandle)
1114   //   LoadBarrier?(LoadP(LoadP(AddP(foo:Klass, #java_mirror))))
1115   //   or NULL if not matching.
1116   BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2();
1117     n = bs->step_over_gc_barrier(n);
1118 
1119   if (n->Opcode() != Op_LoadP) return NULL;
1120 
1121   const TypeInstPtr* tp = phase->type(n)->isa_instptr();
1122   if (!tp || tp->klass() != phase->C->env()->Class_klass()) return NULL;
1123 
1124   Node* adr = n->in(MemNode::Address);
1125   // First load from OopHandle: ((OopHandle)mirror)->resolve(); may need barrier.
1126   if (adr->Opcode() != Op_LoadP || !phase->type(adr)->isa_rawptr()) return NULL;
1127   adr = adr->in(MemNode::Address);
1128 
1129   intptr_t off = 0;
1130   Node* k = AddPNode::Ideal_base_and_offset(adr, phase, off);
1131   if (k == NULL)  return NULL;
1132   const TypeKlassPtr* tkp = phase->type(k)->isa_klassptr();
1133   if (!tkp || off != in_bytes(Klass::java_mirror_offset())) return NULL;
1134 
1135   // We've found the klass node of a Java mirror load.
1136   return k;
1137 }
1138 
1139 static inline Node* isa_const_java_mirror(PhaseGVN* phase, Node* n) {
1140   // for ConP(Foo.class) return ConP(Foo.klass)
1141   // otherwise return NULL
1142   if (!n->is_Con()) return NULL;
1143 
1144   const TypeInstPtr* tp = phase->type(n)->isa_instptr();
1145   if (!tp) return NULL;
1146 
1147   ciType* mirror_type = tp->java_mirror_type();
1148   // TypeInstPtr::java_mirror_type() returns non-NULL for compile-
1149   // time Class constants only.
1150   if (!mirror_type) return NULL;
1151 
1152   // x.getClass() == int.class can never be true (for all primitive types)
1153   // Return a ConP(NULL) node for this case.
1154   if (mirror_type->is_classless()) {
1155     return phase->makecon(TypePtr::NULL_PTR);
1156   }
1157 
1158   // return the ConP(Foo.klass)
1159   assert(mirror_type->is_klass(), "mirror_type should represent a Klass*");
1160   return phase->makecon(TypeKlassPtr::make(mirror_type->as_klass()));
1161 }
1162 
1163 //------------------------------Ideal------------------------------------------
1164 // Normalize comparisons between Java mirror loads to compare the klass instead.
1165 //
1166 // Also check for the case of comparing an unknown klass loaded from the primary
1167 // super-type array vs a known klass with no subtypes.  This amounts to
1168 // checking to see an unknown klass subtypes a known klass with no subtypes;
1169 // this only happens on an exact match.  We can shorten this test by 1 load.
1170 Node* CmpPNode::Ideal(PhaseGVN *phase, bool can_reshape) {
1171   // TODO 8284443 in(1) could be cast?
1172   if (in(1)->is_InlineTypePtr() && phase->type(in(2))->is_zero_type()) {
1173     // Null checking a scalarized but nullable inline type. Check the IsInit
1174     // input instead of the oop input to avoid keeping buffer allocations alive.
1175     return new CmpINode(in(1)->as_InlineTypePtr()->get_is_init(), phase->intcon(0));
1176   }
1177 
1178   // Normalize comparisons between Java mirrors into comparisons of the low-
1179   // level klass, where a dependent load could be shortened.
1180   //
1181   // The new pattern has a nice effect of matching the same pattern used in the
1182   // fast path of instanceof/checkcast/Class.isInstance(), which allows
1183   // redundant exact type check be optimized away by GVN.
1184   // For example, in
1185   //   if (x.getClass() == Foo.class) {
1186   //     Foo foo = (Foo) x;
1187   //     // ... use a ...
1188   //   }
1189   // a CmpPNode could be shared between if_acmpne and checkcast
1190   {
1191     Node* k1 = isa_java_mirror_load(phase, in(1));
1192     Node* k2 = isa_java_mirror_load(phase, in(2));
1193     Node* conk2 = isa_const_java_mirror(phase, in(2));
1194 
1195     if (k1 && (k2 || conk2)) {
1196       Node* lhs = k1;
1197       Node* rhs = (k2 != NULL) ? k2 : conk2;
1198       set_req_X(1, lhs, phase);
1199       set_req_X(2, rhs, phase);
1200       return this;
1201     }
1202   }
1203 
1204   // Constant pointer on right?
1205   const TypeKlassPtr* t2 = phase->type(in(2))->isa_klassptr();
1206   if (t2 == NULL || !t2->klass_is_exact())
1207     return NULL;
1208   // Get the constant klass we are comparing to.
1209   ciKlass* superklass = t2->klass();
1210 
1211   // Now check for LoadKlass on left.
1212   Node* ldk1 = in(1);
1213   if (ldk1->is_DecodeNKlass()) {
1214     ldk1 = ldk1->in(1);
1215     if (ldk1->Opcode() != Op_LoadNKlass )
1216       return NULL;
1217   } else if (ldk1->Opcode() != Op_LoadKlass )
1218     return NULL;
1219   // Take apart the address of the LoadKlass:
1220   Node* adr1 = ldk1->in(MemNode::Address);
1221   intptr_t con2 = 0;
1222   Node* ldk2 = AddPNode::Ideal_base_and_offset(adr1, phase, con2);
1223   if (ldk2 == NULL)
1224     return NULL;
1225   if (con2 == oopDesc::klass_offset_in_bytes()) {
1226     // We are inspecting an object's concrete class.
1227     // Short-circuit the check if the query is abstract.
1228     if (superklass->is_interface() ||
1229         superklass->is_abstract()) {
1230       // Make it come out always false:
1231       this->set_req(2, phase->makecon(TypePtr::NULL_PTR));
1232       return this;
1233     }
1234   }
1235 
1236   // Check for a LoadKlass from primary supertype array.
1237   // Any nested loadklass from loadklass+con must be from the p.s. array.
1238   if (ldk2->is_DecodeNKlass()) {
1239     // Keep ldk2 as DecodeN since it could be used in CmpP below.
1240     if (ldk2->in(1)->Opcode() != Op_LoadNKlass )
1241       return NULL;
1242   } else if (ldk2->Opcode() != Op_LoadKlass)
1243     return NULL;
1244 
1245   // Verify that we understand the situation
1246   if (con2 != (intptr_t) superklass->super_check_offset())
1247     return NULL;                // Might be element-klass loading from array klass
1248 
1249   // Do not fold the subtype check to an array klass pointer comparison for [V? arrays.
1250   // [QMyValue is a subtype of [LMyValue but the klass for [QMyValue is not equal to
1251   // the klass for [LMyValue. Do not bypass the klass load from the primary supertype array.
1252   if (superklass->is_obj_array_klass() && !superklass->as_array_klass()->is_elem_null_free() &&
1253       superklass->as_array_klass()->element_klass()->is_inlinetype()) {
1254     return NULL;
1255   }
1256 
1257   // If 'superklass' has no subklasses and is not an interface, then we are
1258   // assured that the only input which will pass the type check is
1259   // 'superklass' itself.
1260   //
1261   // We could be more liberal here, and allow the optimization on interfaces
1262   // which have a single implementor.  This would require us to increase the
1263   // expressiveness of the add_dependency() mechanism.
1264   // %%% Do this after we fix TypeOopPtr:  Deps are expressive enough now.
1265 
1266   // Object arrays must have their base element have no subtypes
1267   while (superklass->is_obj_array_klass()) {
1268     ciType* elem = superklass->as_obj_array_klass()->element_type();
1269     superklass = elem->as_klass();
1270   }
1271   if (superklass->is_instance_klass()) {
1272     ciInstanceKlass* ik = superklass->as_instance_klass();
1273     if (ik->has_subklass() || ik->is_interface())  return NULL;
1274     // Add a dependency if there is a chance that a subclass will be added later.
1275     if (!ik->is_final()) {
1276       phase->C->dependencies()->assert_leaf_type(ik);
1277     }
1278   }
1279 
1280   // Bypass the dependent load, and compare directly
1281   this->set_req(1,ldk2);
1282 
1283   return this;
1284 }
1285 
1286 //=============================================================================
1287 //------------------------------sub--------------------------------------------
1288 // Simplify an CmpN (compare 2 pointers) node, based on local information.
1289 // If both inputs are constants, compare them.
1290 const Type *CmpNNode::sub( const Type *t1, const Type *t2 ) const {
1291   ShouldNotReachHere();
1292   return bottom_type();
1293 }
1294 
1295 //------------------------------Ideal------------------------------------------
1296 Node *CmpNNode::Ideal( PhaseGVN *phase, bool can_reshape ) {
1297   return NULL;
1298 }
1299 
1300 //=============================================================================
1301 //------------------------------Value------------------------------------------
1302 // Simplify an CmpF (compare 2 floats ) node, based on local information.
1303 // If both inputs are constants, compare them.
1304 const Type* CmpFNode::Value(PhaseGVN* phase) const {
1305   const Node* in1 = in(1);
1306   const Node* in2 = in(2);
1307   // Either input is TOP ==> the result is TOP
1308   const Type* t1 = (in1 == this) ? Type::TOP : phase->type(in1);
1309   if( t1 == Type::TOP ) return Type::TOP;
1310   const Type* t2 = (in2 == this) ? Type::TOP : phase->type(in2);
1311   if( t2 == Type::TOP ) return Type::TOP;
1312 
1313   // Not constants?  Don't know squat - even if they are the same
1314   // value!  If they are NaN's they compare to LT instead of EQ.
1315   const TypeF *tf1 = t1->isa_float_constant();
1316   const TypeF *tf2 = t2->isa_float_constant();
1317   if( !tf1 || !tf2 ) return TypeInt::CC;
1318 
1319   // This implements the Java bytecode fcmpl, so unordered returns -1.
1320   if( tf1->is_nan() || tf2->is_nan() )
1321     return TypeInt::CC_LT;
1322 
1323   if( tf1->_f < tf2->_f ) return TypeInt::CC_LT;
1324   if( tf1->_f > tf2->_f ) return TypeInt::CC_GT;
1325   assert( tf1->_f == tf2->_f, "do not understand FP behavior" );
1326   return TypeInt::CC_EQ;
1327 }
1328 
1329 
1330 //=============================================================================
1331 //------------------------------Value------------------------------------------
1332 // Simplify an CmpD (compare 2 doubles ) node, based on local information.
1333 // If both inputs are constants, compare them.
1334 const Type* CmpDNode::Value(PhaseGVN* phase) const {
1335   const Node* in1 = in(1);
1336   const Node* in2 = in(2);
1337   // Either input is TOP ==> the result is TOP
1338   const Type* t1 = (in1 == this) ? Type::TOP : phase->type(in1);
1339   if( t1 == Type::TOP ) return Type::TOP;
1340   const Type* t2 = (in2 == this) ? Type::TOP : phase->type(in2);
1341   if( t2 == Type::TOP ) return Type::TOP;
1342 
1343   // Not constants?  Don't know squat - even if they are the same
1344   // value!  If they are NaN's they compare to LT instead of EQ.
1345   const TypeD *td1 = t1->isa_double_constant();
1346   const TypeD *td2 = t2->isa_double_constant();
1347   if( !td1 || !td2 ) return TypeInt::CC;
1348 
1349   // This implements the Java bytecode dcmpl, so unordered returns -1.
1350   if( td1->is_nan() || td2->is_nan() )
1351     return TypeInt::CC_LT;
1352 
1353   if( td1->_d < td2->_d ) return TypeInt::CC_LT;
1354   if( td1->_d > td2->_d ) return TypeInt::CC_GT;
1355   assert( td1->_d == td2->_d, "do not understand FP behavior" );
1356   return TypeInt::CC_EQ;
1357 }
1358 
1359 //------------------------------Ideal------------------------------------------
1360 Node *CmpDNode::Ideal(PhaseGVN *phase, bool can_reshape){
1361   // Check if we can change this to a CmpF and remove a ConvD2F operation.
1362   // Change  (CMPD (F2D (float)) (ConD value))
1363   // To      (CMPF      (float)  (ConF value))
1364   // Valid when 'value' does not lose precision as a float.
1365   // Benefits: eliminates conversion, does not require 24-bit mode
1366 
1367   // NaNs prevent commuting operands.  This transform works regardless of the
1368   // order of ConD and ConvF2D inputs by preserving the original order.
1369   int idx_f2d = 1;              // ConvF2D on left side?
1370   if( in(idx_f2d)->Opcode() != Op_ConvF2D )
1371     idx_f2d = 2;                // No, swap to check for reversed args
1372   int idx_con = 3-idx_f2d;      // Check for the constant on other input
1373 
1374   if( ConvertCmpD2CmpF &&
1375       in(idx_f2d)->Opcode() == Op_ConvF2D &&
1376       in(idx_con)->Opcode() == Op_ConD ) {
1377     const TypeD *t2 = in(idx_con)->bottom_type()->is_double_constant();
1378     double t2_value_as_double = t2->_d;
1379     float  t2_value_as_float  = (float)t2_value_as_double;
1380     if( t2_value_as_double == (double)t2_value_as_float ) {
1381       // Test value can be represented as a float
1382       // Eliminate the conversion to double and create new comparison
1383       Node *new_in1 = in(idx_f2d)->in(1);
1384       Node *new_in2 = phase->makecon( TypeF::make(t2_value_as_float) );
1385       if( idx_f2d != 1 ) {      // Must flip args to match original order
1386         Node *tmp = new_in1;
1387         new_in1 = new_in2;
1388         new_in2 = tmp;
1389       }
1390       CmpFNode *new_cmp = (Opcode() == Op_CmpD3)
1391         ? new CmpF3Node( new_in1, new_in2 )
1392         : new CmpFNode ( new_in1, new_in2 ) ;
1393       return new_cmp;           // Changed to CmpFNode
1394     }
1395     // Testing value required the precision of a double
1396   }
1397   return NULL;                  // No change
1398 }
1399 
1400 //=============================================================================
1401 //------------------------------Value------------------------------------------
1402 const Type* FlatArrayCheckNode::Value(PhaseGVN* phase) const {
1403   bool all_not_flat = true;
1404   for (uint i = ArrayOrKlass; i < req(); ++i) {
1405     const Type* t = phase->type(in(i));
1406     if (t == Type::TOP) {
1407       return Type::TOP;
1408     }
1409     if (t->is_ptr()->is_flat()) {
1410       // One of the input arrays is flat, check always passes
1411       return TypeInt::CC_EQ;
1412     } else if (!t->is_ptr()->is_not_flat()) {
1413       // One of the input arrays might be flat
1414       all_not_flat = false;
1415     }
1416   }
1417   if (all_not_flat) {
1418     // None of the input arrays can be flat, check always fails
1419     return TypeInt::CC_GT;
1420   }
1421   return TypeInt::CC;
1422 }
1423 
1424 //------------------------------Ideal------------------------------------------
1425 Node* FlatArrayCheckNode::Ideal(PhaseGVN* phase, bool can_reshape) {
1426   bool changed = false;
1427   // Remove inputs that are known to be non-flat
1428   for (uint i = ArrayOrKlass; i < req(); ++i) {
1429     const Type* t = phase->type(in(i));
1430     if (t->isa_ptr() && t->is_ptr()->is_not_flat()) {
1431       del_req(i--);
1432       changed = true;
1433     }
1434   }
1435   return changed ? this : NULL;
1436 }
1437 
1438 //=============================================================================
1439 //------------------------------cc2logical-------------------------------------
1440 // Convert a condition code type to a logical type
1441 const Type *BoolTest::cc2logical( const Type *CC ) const {
1442   if( CC == Type::TOP ) return Type::TOP;
1443   if( CC->base() != Type::Int ) return TypeInt::BOOL; // Bottom or worse
1444   const TypeInt *ti = CC->is_int();
1445   if( ti->is_con() ) {          // Only 1 kind of condition codes set?
1446     // Match low order 2 bits
1447     int tmp = ((ti->get_con()&3) == (_test&3)) ? 1 : 0;
1448     if( _test & 4 ) tmp = 1-tmp;     // Optionally complement result
1449     return TypeInt::make(tmp);       // Boolean result
1450   }
1451 
1452   if( CC == TypeInt::CC_GE ) {
1453     if( _test == ge ) return TypeInt::ONE;
1454     if( _test == lt ) return TypeInt::ZERO;
1455   }
1456   if( CC == TypeInt::CC_LE ) {
1457     if( _test == le ) return TypeInt::ONE;
1458     if( _test == gt ) return TypeInt::ZERO;
1459   }
1460 
1461   return TypeInt::BOOL;
1462 }
1463 
1464 //------------------------------dump_spec-------------------------------------
1465 // Print special per-node info
1466 void BoolTest::dump_on(outputStream *st) const {
1467   const char *msg[] = {"eq","gt","of","lt","ne","le","nof","ge"};
1468   st->print("%s", msg[_test]);
1469 }
1470 
1471 // Returns the logical AND of two tests (or 'never' if both tests can never be true).
1472 // For example, a test for 'le' followed by a test for 'lt' is equivalent with 'lt'.
1473 BoolTest::mask BoolTest::merge(BoolTest other) const {
1474   const mask res[illegal+1][illegal+1] = {
1475     // eq,      gt,      of,      lt,      ne,      le,      nof,     ge,      never,   illegal
1476       {eq,      never,   illegal, never,   never,   eq,      illegal, eq,      never,   illegal},  // eq
1477       {never,   gt,      illegal, never,   gt,      never,   illegal, gt,      never,   illegal},  // gt
1478       {illegal, illegal, illegal, illegal, illegal, illegal, illegal, illegal, never,   illegal},  // of
1479       {never,   never,   illegal, lt,      lt,      lt,      illegal, never,   never,   illegal},  // lt
1480       {never,   gt,      illegal, lt,      ne,      lt,      illegal, gt,      never,   illegal},  // ne
1481       {eq,      never,   illegal, lt,      lt,      le,      illegal, eq,      never,   illegal},  // le
1482       {illegal, illegal, illegal, illegal, illegal, illegal, illegal, illegal, never,   illegal},  // nof
1483       {eq,      gt,      illegal, never,   gt,      eq,      illegal, ge,      never,   illegal},  // ge
1484       {never,   never,   never,   never,   never,   never,   never,   never,   never,   illegal},  // never
1485       {illegal, illegal, illegal, illegal, illegal, illegal, illegal, illegal, illegal, illegal}}; // illegal
1486   return res[_test][other._test];
1487 }
1488 
1489 //=============================================================================
1490 uint BoolNode::hash() const { return (Node::hash() << 3)|(_test._test+1); }
1491 uint BoolNode::size_of() const { return sizeof(BoolNode); }
1492 
1493 //------------------------------operator==-------------------------------------
1494 bool BoolNode::cmp( const Node &n ) const {
1495   const BoolNode *b = (const BoolNode *)&n; // Cast up
1496   return (_test._test == b->_test._test);
1497 }
1498 
1499 //-------------------------------make_predicate--------------------------------
1500 Node* BoolNode::make_predicate(Node* test_value, PhaseGVN* phase) {
1501   if (test_value->is_Con())   return test_value;
1502   if (test_value->is_Bool())  return test_value;
1503   if (test_value->is_CMove() &&
1504       test_value->in(CMoveNode::Condition)->is_Bool()) {
1505     BoolNode*   bol   = test_value->in(CMoveNode::Condition)->as_Bool();
1506     const Type* ftype = phase->type(test_value->in(CMoveNode::IfFalse));
1507     const Type* ttype = phase->type(test_value->in(CMoveNode::IfTrue));
1508     if (ftype == TypeInt::ZERO && !TypeInt::ZERO->higher_equal(ttype)) {
1509       return bol;
1510     } else if (ttype == TypeInt::ZERO && !TypeInt::ZERO->higher_equal(ftype)) {
1511       return phase->transform( bol->negate(phase) );
1512     }
1513     // Else fall through.  The CMove gets in the way of the test.
1514     // It should be the case that make_predicate(bol->as_int_value()) == bol.
1515   }
1516   Node* cmp = new CmpINode(test_value, phase->intcon(0));
1517   cmp = phase->transform(cmp);
1518   Node* bol = new BoolNode(cmp, BoolTest::ne);
1519   return phase->transform(bol);
1520 }
1521 
1522 //--------------------------------as_int_value---------------------------------
1523 Node* BoolNode::as_int_value(PhaseGVN* phase) {
1524   // Inverse to make_predicate.  The CMove probably boils down to a Conv2B.
1525   Node* cmov = CMoveNode::make(NULL, this,
1526                                phase->intcon(0), phase->intcon(1),
1527                                TypeInt::BOOL);
1528   return phase->transform(cmov);
1529 }
1530 
1531 //----------------------------------negate-------------------------------------
1532 BoolNode* BoolNode::negate(PhaseGVN* phase) {
1533   return new BoolNode(in(1), _test.negate());
1534 }
1535 
1536 // Change "bool eq/ne (cmp (add/sub A B) C)" into false/true if add/sub
1537 // overflows and we can prove that C is not in the two resulting ranges.
1538 // This optimization is similar to the one performed by CmpUNode::Value().
1539 Node* BoolNode::fold_cmpI(PhaseGVN* phase, SubNode* cmp, Node* cmp1, int cmp_op,
1540                           int cmp1_op, const TypeInt* cmp2_type) {
1541   // Only optimize eq/ne integer comparison of add/sub
1542   if((_test._test == BoolTest::eq || _test._test == BoolTest::ne) &&
1543      (cmp_op == Op_CmpI) && (cmp1_op == Op_AddI || cmp1_op == Op_SubI)) {
1544     // Skip cases were inputs of add/sub are not integers or of bottom type
1545     const TypeInt* r0 = phase->type(cmp1->in(1))->isa_int();
1546     const TypeInt* r1 = phase->type(cmp1->in(2))->isa_int();
1547     if ((r0 != NULL) && (r0 != TypeInt::INT) &&
1548         (r1 != NULL) && (r1 != TypeInt::INT) &&
1549         (cmp2_type != TypeInt::INT)) {
1550       // Compute exact (long) type range of add/sub result
1551       jlong lo_long = r0->_lo;
1552       jlong hi_long = r0->_hi;
1553       if (cmp1_op == Op_AddI) {
1554         lo_long += r1->_lo;
1555         hi_long += r1->_hi;
1556       } else {
1557         lo_long -= r1->_hi;
1558         hi_long -= r1->_lo;
1559       }
1560       // Check for over-/underflow by casting to integer
1561       int lo_int = (int)lo_long;
1562       int hi_int = (int)hi_long;
1563       bool underflow = lo_long != (jlong)lo_int;
1564       bool overflow  = hi_long != (jlong)hi_int;
1565       if ((underflow != overflow) && (hi_int < lo_int)) {
1566         // Overflow on one boundary, compute resulting type ranges:
1567         // tr1 [MIN_INT, hi_int] and tr2 [lo_int, MAX_INT]
1568         int w = MAX2(r0->_widen, r1->_widen); // _widen does not matter here
1569         const TypeInt* tr1 = TypeInt::make(min_jint, hi_int, w);
1570         const TypeInt* tr2 = TypeInt::make(lo_int, max_jint, w);
1571         // Compare second input of cmp to both type ranges
1572         const Type* sub_tr1 = cmp->sub(tr1, cmp2_type);
1573         const Type* sub_tr2 = cmp->sub(tr2, cmp2_type);
1574         if (sub_tr1 == TypeInt::CC_LT && sub_tr2 == TypeInt::CC_GT) {
1575           // The result of the add/sub will never equal cmp2. Replace BoolNode
1576           // by false (0) if it tests for equality and by true (1) otherwise.
1577           return ConINode::make((_test._test == BoolTest::eq) ? 0 : 1);
1578         }
1579       }
1580     }
1581   }
1582   return NULL;
1583 }
1584 
1585 static bool is_counted_loop_cmp(Node *cmp) {
1586   Node *n = cmp->in(1)->in(1);
1587   return n != NULL &&
1588          n->is_Phi() &&
1589          n->in(0) != NULL &&
1590          n->in(0)->is_CountedLoop() &&
1591          n->in(0)->as_CountedLoop()->phi() == n;
1592 }
1593 
1594 //------------------------------Ideal------------------------------------------
1595 Node *BoolNode::Ideal(PhaseGVN *phase, bool can_reshape) {
1596   // Change "bool tst (cmp con x)" into "bool ~tst (cmp x con)".
1597   // This moves the constant to the right.  Helps value-numbering.
1598   Node *cmp = in(1);
1599   if( !cmp->is_Sub() ) return NULL;
1600   int cop = cmp->Opcode();
1601   if( cop == Op_FastLock || cop == Op_FastUnlock || cmp->is_SubTypeCheck()) return NULL;
1602   Node *cmp1 = cmp->in(1);
1603   Node *cmp2 = cmp->in(2);
1604   if( !cmp1 ) return NULL;
1605 
1606   if (_test._test == BoolTest::overflow || _test._test == BoolTest::no_overflow) {
1607     return NULL;
1608   }
1609 
1610   const int cmp1_op = cmp1->Opcode();
1611   const int cmp2_op = cmp2->Opcode();
1612 
1613   // Constant on left?
1614   Node *con = cmp1;
1615   // Move constants to the right of compare's to canonicalize.
1616   // Do not muck with Opaque1 nodes, as this indicates a loop
1617   // guard that cannot change shape.
1618   if( con->is_Con() && !cmp2->is_Con() && cmp2_op != Op_Opaque1 &&
1619       // Because of NaN's, CmpD and CmpF are not commutative
1620       cop != Op_CmpD && cop != Op_CmpF &&
1621       // Protect against swapping inputs to a compare when it is used by a
1622       // counted loop exit, which requires maintaining the loop-limit as in(2)
1623       !is_counted_loop_exit_test() ) {
1624     // Ok, commute the constant to the right of the cmp node.
1625     // Clone the Node, getting a new Node of the same class
1626     cmp = cmp->clone();
1627     // Swap inputs to the clone
1628     cmp->swap_edges(1, 2);
1629     cmp = phase->transform( cmp );
1630     return new BoolNode( cmp, _test.commute() );
1631   }
1632 
1633   // Change "bool eq/ne (cmp (and X 16) 16)" into "bool ne/eq (cmp (and X 16) 0)".
1634   if (cop == Op_CmpI &&
1635       (_test._test == BoolTest::eq || _test._test == BoolTest::ne) &&
1636       cmp1_op == Op_AndI && cmp2_op == Op_ConI &&
1637       cmp1->in(2)->Opcode() == Op_ConI) {
1638     const TypeInt *t12 = phase->type(cmp2)->isa_int();
1639     const TypeInt *t112 = phase->type(cmp1->in(2))->isa_int();
1640     if (t12 && t12->is_con() && t112 && t112->is_con() &&
1641         t12->get_con() == t112->get_con() && is_power_of_2(t12->get_con())) {
1642       Node *ncmp = phase->transform(new CmpINode(cmp1, phase->intcon(0)));
1643       return new BoolNode(ncmp, _test.negate());
1644     }
1645   }
1646 
1647   // Same for long type: change "bool eq/ne (cmp (and X 16) 16)" into "bool ne/eq (cmp (and X 16) 0)".
1648   if (cop == Op_CmpL &&
1649       (_test._test == BoolTest::eq || _test._test == BoolTest::ne) &&
1650       cmp1_op == Op_AndL && cmp2_op == Op_ConL &&
1651       cmp1->in(2)->Opcode() == Op_ConL) {
1652     const TypeLong *t12 = phase->type(cmp2)->isa_long();
1653     const TypeLong *t112 = phase->type(cmp1->in(2))->isa_long();
1654     if (t12 && t12->is_con() && t112 && t112->is_con() &&
1655         t12->get_con() == t112->get_con() && is_power_of_2(t12->get_con())) {
1656       Node *ncmp = phase->transform(new CmpLNode(cmp1, phase->longcon(0)));
1657       return new BoolNode(ncmp, _test.negate());
1658     }
1659   }
1660 
1661   // Change "cmp (add X min_jint) (add Y min_jint)" into "cmpu X Y"
1662   // and    "cmp (add X min_jint) c" into "cmpu X (c + min_jint)"
1663   if (cop == Op_CmpI &&
1664       cmp1_op == Op_AddI &&
1665       phase->type(cmp1->in(2)) == TypeInt::MIN) {
1666     if (cmp2_op == Op_ConI) {
1667       Node* ncmp2 = phase->intcon(java_add(cmp2->get_int(), min_jint));
1668       Node* ncmp = phase->transform(new CmpUNode(cmp1->in(1), ncmp2));
1669       return new BoolNode(ncmp, _test._test);
1670     } else if (cmp2_op == Op_AddI &&
1671                phase->type(cmp2->in(2)) == TypeInt::MIN) {
1672       Node* ncmp = phase->transform(new CmpUNode(cmp1->in(1), cmp2->in(1)));
1673       return new BoolNode(ncmp, _test._test);
1674     }
1675   }
1676 
1677   // Change "cmp (add X min_jlong) (add Y min_jlong)" into "cmpu X Y"
1678   // and    "cmp (add X min_jlong) c" into "cmpu X (c + min_jlong)"
1679   if (cop == Op_CmpL &&
1680       cmp1_op == Op_AddL &&
1681       phase->type(cmp1->in(2)) == TypeLong::MIN) {
1682     if (cmp2_op == Op_ConL) {
1683       Node* ncmp2 = phase->longcon(java_add(cmp2->get_long(), min_jlong));
1684       Node* ncmp = phase->transform(new CmpULNode(cmp1->in(1), ncmp2));
1685       return new BoolNode(ncmp, _test._test);
1686     } else if (cmp2_op == Op_AddL &&
1687                phase->type(cmp2->in(2)) == TypeLong::MIN) {
1688       Node* ncmp = phase->transform(new CmpULNode(cmp1->in(1), cmp2->in(1)));
1689       return new BoolNode(ncmp, _test._test);
1690     }
1691   }
1692 
1693   // Change "bool eq/ne (cmp (xor X 1) 0)" into "bool ne/eq (cmp X 0)".
1694   // The XOR-1 is an idiom used to flip the sense of a bool.  We flip the
1695   // test instead.
1696   const TypeInt* cmp2_type = phase->type(cmp2)->isa_int();
1697   if (cmp2_type == NULL)  return NULL;
1698   Node* j_xor = cmp1;
1699   if( cmp2_type == TypeInt::ZERO &&
1700       cmp1_op == Op_XorI &&
1701       j_xor->in(1) != j_xor &&          // An xor of itself is dead
1702       phase->type( j_xor->in(1) ) == TypeInt::BOOL &&
1703       phase->type( j_xor->in(2) ) == TypeInt::ONE &&
1704       (_test._test == BoolTest::eq ||
1705        _test._test == BoolTest::ne) ) {
1706     Node *ncmp = phase->transform(new CmpINode(j_xor->in(1),cmp2));
1707     return new BoolNode( ncmp, _test.negate() );
1708   }
1709 
1710   // Change ((x & m) u<= m) or ((m & x) u<= m) to always true
1711   // Same with ((x & m) u< m+1) and ((m & x) u< m+1)
1712   if (cop == Op_CmpU &&
1713       cmp1_op == Op_AndI) {
1714     Node* bound = NULL;
1715     if (_test._test == BoolTest::le) {
1716       bound = cmp2;
1717     } else if (_test._test == BoolTest::lt &&
1718                cmp2->Opcode() == Op_AddI &&
1719                cmp2->in(2)->find_int_con(0) == 1) {
1720       bound = cmp2->in(1);
1721     }
1722     if (cmp1->in(2) == bound || cmp1->in(1) == bound) {
1723       return ConINode::make(1);
1724     }
1725   }
1726 
1727   // Change ((x & (m - 1)) u< m) into (m > 0)
1728   // This is the off-by-one variant of the above
1729   if (cop == Op_CmpU &&
1730       _test._test == BoolTest::lt &&
1731       cmp1_op == Op_AndI) {
1732     Node* l = cmp1->in(1);
1733     Node* r = cmp1->in(2);
1734     for (int repeat = 0; repeat < 2; repeat++) {
1735       bool match = r->Opcode() == Op_AddI && r->in(2)->find_int_con(0) == -1 &&
1736                    r->in(1) == cmp2;
1737       if (match) {
1738         // arraylength known to be non-negative, so a (arraylength != 0) is sufficient,
1739         // but to be compatible with the array range check pattern, use (arraylength u> 0)
1740         Node* ncmp = cmp2->Opcode() == Op_LoadRange
1741                      ? phase->transform(new CmpUNode(cmp2, phase->intcon(0)))
1742                      : phase->transform(new CmpINode(cmp2, phase->intcon(0)));
1743         return new BoolNode(ncmp, BoolTest::gt);
1744       } else {
1745         // commute and try again
1746         l = cmp1->in(2);
1747         r = cmp1->in(1);
1748       }
1749     }
1750   }
1751 
1752   // Change x u< 1 or x u<= 0 to x == 0
1753   if (cop == Op_CmpU &&
1754       cmp1_op != Op_LoadRange &&
1755       ((_test._test == BoolTest::lt &&
1756         cmp2->find_int_con(-1) == 1) ||
1757        (_test._test == BoolTest::le &&
1758         cmp2->find_int_con(-1) == 0))) {
1759     Node* ncmp = phase->transform(new CmpINode(cmp1, phase->intcon(0)));
1760     return new BoolNode(ncmp, BoolTest::eq);
1761   }
1762 
1763   // Change (arraylength <= 0) or (arraylength == 0)
1764   //   into (arraylength u<= 0)
1765   // Also change (arraylength != 0) into (arraylength u> 0)
1766   // The latter version matches the code pattern generated for
1767   // array range checks, which will more likely be optimized later.
1768   if (cop == Op_CmpI &&
1769       cmp1_op == Op_LoadRange &&
1770       cmp2->find_int_con(-1) == 0) {
1771     if (_test._test == BoolTest::le || _test._test == BoolTest::eq) {
1772       Node* ncmp = phase->transform(new CmpUNode(cmp1, cmp2));
1773       return new BoolNode(ncmp, BoolTest::le);
1774     } else if (_test._test == BoolTest::ne) {
1775       Node* ncmp = phase->transform(new CmpUNode(cmp1, cmp2));
1776       return new BoolNode(ncmp, BoolTest::gt);
1777     }
1778   }
1779 
1780   // Change "bool eq/ne (cmp (Conv2B X) 0)" into "bool eq/ne (cmp X 0)".
1781   // This is a standard idiom for branching on a boolean value.
1782   Node *c2b = cmp1;
1783   if( cmp2_type == TypeInt::ZERO &&
1784       cmp1_op == Op_Conv2B &&
1785       (_test._test == BoolTest::eq ||
1786        _test._test == BoolTest::ne) ) {
1787     Node *ncmp = phase->transform(phase->type(c2b->in(1))->isa_int()
1788        ? (Node*)new CmpINode(c2b->in(1),cmp2)
1789        : (Node*)new CmpPNode(c2b->in(1),phase->makecon(TypePtr::NULL_PTR))
1790     );
1791     return new BoolNode( ncmp, _test._test );
1792   }
1793 
1794   // Comparing a SubI against a zero is equal to comparing the SubI
1795   // arguments directly.  This only works for eq and ne comparisons
1796   // due to possible integer overflow.
1797   if ((_test._test == BoolTest::eq || _test._test == BoolTest::ne) &&
1798         (cop == Op_CmpI) &&
1799         (cmp1_op == Op_SubI) &&
1800         ( cmp2_type == TypeInt::ZERO ) ) {
1801     Node *ncmp = phase->transform( new CmpINode(cmp1->in(1),cmp1->in(2)));
1802     return new BoolNode( ncmp, _test._test );
1803   }
1804 
1805   // Same as above but with and AddI of a constant
1806   if ((_test._test == BoolTest::eq || _test._test == BoolTest::ne) &&
1807       cop == Op_CmpI &&
1808       cmp1_op == Op_AddI &&
1809       cmp1->in(2) != NULL &&
1810       phase->type(cmp1->in(2))->isa_int() &&
1811       phase->type(cmp1->in(2))->is_int()->is_con() &&
1812       cmp2_type == TypeInt::ZERO &&
1813       !is_counted_loop_cmp(cmp) // modifying the exit test of a counted loop messes the counted loop shape
1814       ) {
1815     const TypeInt* cmp1_in2 = phase->type(cmp1->in(2))->is_int();
1816     Node *ncmp = phase->transform( new CmpINode(cmp1->in(1),phase->intcon(-cmp1_in2->_hi)));
1817     return new BoolNode( ncmp, _test._test );
1818   }
1819 
1820   // Change "bool eq/ne (cmp (phi (X -X) 0))" into "bool eq/ne (cmp X 0)"
1821   // since zero check of conditional negation of an integer is equal to
1822   // zero check of the integer directly.
1823   if ((_test._test == BoolTest::eq || _test._test == BoolTest::ne) &&
1824       (cop == Op_CmpI) &&
1825       (cmp2_type == TypeInt::ZERO) &&
1826       (cmp1_op == Op_Phi)) {
1827     // There should be a diamond phi with true path at index 1 or 2
1828     PhiNode *phi = cmp1->as_Phi();
1829     int idx_true = phi->is_diamond_phi();
1830     if (idx_true != 0) {
1831       // True input is in(idx_true) while false input is in(3 - idx_true)
1832       Node *tin = phi->in(idx_true);
1833       Node *fin = phi->in(3 - idx_true);
1834       if ((tin->Opcode() == Op_SubI) &&
1835           (phase->type(tin->in(1)) == TypeInt::ZERO) &&
1836           (tin->in(2) == fin)) {
1837         // Found conditional negation at true path, create a new CmpINode without that
1838         Node *ncmp = phase->transform(new CmpINode(fin, cmp2));
1839         return new BoolNode(ncmp, _test._test);
1840       }
1841       if ((fin->Opcode() == Op_SubI) &&
1842           (phase->type(fin->in(1)) == TypeInt::ZERO) &&
1843           (fin->in(2) == tin)) {
1844         // Found conditional negation at false path, create a new CmpINode without that
1845         Node *ncmp = phase->transform(new CmpINode(tin, cmp2));
1846         return new BoolNode(ncmp, _test._test);
1847       }
1848     }
1849   }
1850 
1851   // Change (-A vs 0) into (A vs 0) by commuting the test.  Disallow in the
1852   // most general case because negating 0x80000000 does nothing.  Needed for
1853   // the CmpF3/SubI/CmpI idiom.
1854   if( cop == Op_CmpI &&
1855       cmp1_op == Op_SubI &&
1856       cmp2_type == TypeInt::ZERO &&
1857       phase->type( cmp1->in(1) ) == TypeInt::ZERO &&
1858       phase->type( cmp1->in(2) )->higher_equal(TypeInt::SYMINT) ) {
1859     Node *ncmp = phase->transform( new CmpINode(cmp1->in(2),cmp2));
1860     return new BoolNode( ncmp, _test.commute() );
1861   }
1862 
1863   // Try to optimize signed integer comparison
1864   return fold_cmpI(phase, cmp->as_Sub(), cmp1, cop, cmp1_op, cmp2_type);
1865 
1866   //  The transformation below is not valid for either signed or unsigned
1867   //  comparisons due to wraparound concerns at MAX_VALUE and MIN_VALUE.
1868   //  This transformation can be resurrected when we are able to
1869   //  make inferences about the range of values being subtracted from
1870   //  (or added to) relative to the wraparound point.
1871   //
1872   //    // Remove +/-1's if possible.
1873   //    // "X <= Y-1" becomes "X <  Y"
1874   //    // "X+1 <= Y" becomes "X <  Y"
1875   //    // "X <  Y+1" becomes "X <= Y"
1876   //    // "X-1 <  Y" becomes "X <= Y"
1877   //    // Do not this to compares off of the counted-loop-end.  These guys are
1878   //    // checking the trip counter and they want to use the post-incremented
1879   //    // counter.  If they use the PRE-incremented counter, then the counter has
1880   //    // to be incremented in a private block on a loop backedge.
1881   //    if( du && du->cnt(this) && du->out(this)[0]->Opcode() == Op_CountedLoopEnd )
1882   //      return NULL;
1883   //  #ifndef PRODUCT
1884   //    // Do not do this in a wash GVN pass during verification.
1885   //    // Gets triggered by too many simple optimizations to be bothered with
1886   //    // re-trying it again and again.
1887   //    if( !phase->allow_progress() ) return NULL;
1888   //  #endif
1889   //    // Not valid for unsigned compare because of corner cases in involving zero.
1890   //    // For example, replacing "X-1 <u Y" with "X <=u Y" fails to throw an
1891   //    // exception in case X is 0 (because 0-1 turns into 4billion unsigned but
1892   //    // "0 <=u Y" is always true).
1893   //    if( cmp->Opcode() == Op_CmpU ) return NULL;
1894   //    int cmp2_op = cmp2->Opcode();
1895   //    if( _test._test == BoolTest::le ) {
1896   //      if( cmp1_op == Op_AddI &&
1897   //          phase->type( cmp1->in(2) ) == TypeInt::ONE )
1898   //        return clone_cmp( cmp, cmp1->in(1), cmp2, phase, BoolTest::lt );
1899   //      else if( cmp2_op == Op_AddI &&
1900   //         phase->type( cmp2->in(2) ) == TypeInt::MINUS_1 )
1901   //        return clone_cmp( cmp, cmp1, cmp2->in(1), phase, BoolTest::lt );
1902   //    } else if( _test._test == BoolTest::lt ) {
1903   //      if( cmp1_op == Op_AddI &&
1904   //          phase->type( cmp1->in(2) ) == TypeInt::MINUS_1 )
1905   //        return clone_cmp( cmp, cmp1->in(1), cmp2, phase, BoolTest::le );
1906   //      else if( cmp2_op == Op_AddI &&
1907   //         phase->type( cmp2->in(2) ) == TypeInt::ONE )
1908   //        return clone_cmp( cmp, cmp1, cmp2->in(1), phase, BoolTest::le );
1909   //    }
1910 }
1911 
1912 //------------------------------Value------------------------------------------
1913 // Simplify a Bool (convert condition codes to boolean (1 or 0)) node,
1914 // based on local information.   If the input is constant, do it.
1915 const Type* BoolNode::Value(PhaseGVN* phase) const {
1916   return _test.cc2logical( phase->type( in(1) ) );
1917 }
1918 
1919 #ifndef PRODUCT
1920 //------------------------------dump_spec--------------------------------------
1921 // Dump special per-node info
1922 void BoolNode::dump_spec(outputStream *st) const {
1923   st->print("[");
1924   _test.dump_on(st);
1925   st->print("]");
1926 }
1927 
1928 //-------------------------------related---------------------------------------
1929 // A BoolNode's related nodes are all of its data inputs, and all of its
1930 // outputs until control nodes are hit, which are included. In compact
1931 // representation, inputs till level 3 and immediate outputs are included.
1932 void BoolNode::related(GrowableArray<Node*> *in_rel, GrowableArray<Node*> *out_rel, bool compact) const {
1933   if (compact) {
1934     this->collect_nodes(in_rel, 3, false, true);
1935     this->collect_nodes(out_rel, -1, false, false);
1936   } else {
1937     this->collect_nodes_in_all_data(in_rel, false);
1938     this->collect_nodes_out_all_ctrl_boundary(out_rel);
1939   }
1940 }
1941 #endif
1942 
1943 //----------------------is_counted_loop_exit_test------------------------------
1944 // Returns true if node is used by a counted loop node.
1945 bool BoolNode::is_counted_loop_exit_test() {
1946   for( DUIterator_Fast imax, i = fast_outs(imax); i < imax; i++ ) {
1947     Node* use = fast_out(i);
1948     if (use->is_CountedLoopEnd()) {
1949       return true;
1950     }
1951   }
1952   return false;
1953 }
1954 
1955 //=============================================================================
1956 //------------------------------Value------------------------------------------
1957 const Type* AbsNode::Value(PhaseGVN* phase) const {
1958   const Type* t1 = phase->type(in(1));
1959   if (t1 == Type::TOP) return Type::TOP;
1960 
1961   switch (t1->base()) {
1962   case Type::Int: {
1963     const TypeInt* ti = t1->is_int();
1964     if (ti->is_con()) {
1965       return TypeInt::make(uabs(ti->get_con()));
1966     }
1967     break;
1968   }
1969   case Type::Long: {
1970     const TypeLong* tl = t1->is_long();
1971     if (tl->is_con()) {
1972       return TypeLong::make(uabs(tl->get_con()));
1973     }
1974     break;
1975   }
1976   case Type::FloatCon:
1977     return TypeF::make(abs(t1->getf()));
1978   case Type::DoubleCon:
1979     return TypeD::make(abs(t1->getd()));
1980   default:
1981     break;
1982   }
1983 
1984   return bottom_type();
1985 }
1986 
1987 //------------------------------Identity----------------------------------------
1988 Node* AbsNode::Identity(PhaseGVN* phase) {
1989   Node* in1 = in(1);
1990   // No need to do abs for non-negative values
1991   if (phase->type(in1)->higher_equal(TypeInt::POS) ||
1992       phase->type(in1)->higher_equal(TypeLong::POS)) {
1993     return in1;
1994   }
1995   // Convert "abs(abs(x))" into "abs(x)"
1996   if (in1->Opcode() == Opcode()) {
1997     return in1;
1998   }
1999   return this;
2000 }
2001 
2002 //------------------------------Ideal------------------------------------------
2003 Node* AbsNode::Ideal(PhaseGVN* phase, bool can_reshape) {
2004   Node* in1 = in(1);
2005   // Convert "abs(0-x)" into "abs(x)"
2006   if (in1->is_Sub() && phase->type(in1->in(1))->is_zero_type()) {
2007     set_req_X(1, in1->in(2), phase);
2008     return this;
2009   }
2010   return NULL;
2011 }
2012 
2013 //=============================================================================
2014 //------------------------------Value------------------------------------------
2015 // Compute sqrt
2016 const Type* SqrtDNode::Value(PhaseGVN* phase) const {
2017   const Type *t1 = phase->type( in(1) );
2018   if( t1 == Type::TOP ) return Type::TOP;
2019   if( t1->base() != Type::DoubleCon ) return Type::DOUBLE;
2020   double d = t1->getd();
2021   if( d < 0.0 ) return Type::DOUBLE;
2022   return TypeD::make( sqrt( d ) );
2023 }
2024 
2025 const Type* SqrtFNode::Value(PhaseGVN* phase) const {
2026   const Type *t1 = phase->type( in(1) );
2027   if( t1 == Type::TOP ) return Type::TOP;
2028   if( t1->base() != Type::FloatCon ) return Type::FLOAT;
2029   float f = t1->getf();
2030   if( f < 0.0f ) return Type::FLOAT;
2031   return TypeF::make( (float)sqrt( (double)f ) );
2032 }