1 /*
   2  * Copyright (c) 1997, 2023, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
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  23  */
  24 
  25 #include "precompiled.hpp"
  26 #include "memory/allocation.inline.hpp"
  27 #include "opto/addnode.hpp"
  28 #include "opto/castnode.hpp"
  29 #include "opto/cfgnode.hpp"
  30 #include "opto/connode.hpp"
  31 #include "opto/machnode.hpp"
  32 #include "opto/movenode.hpp"
  33 #include "opto/mulnode.hpp"
  34 #include "opto/phaseX.hpp"
  35 #include "opto/subnode.hpp"
  36 
  37 // Portions of code courtesy of Clifford Click
  38 
  39 // Classic Add functionality.  This covers all the usual 'add' behaviors for
  40 // an algebraic ring.  Add-integer, add-float, add-double, and binary-or are
  41 // all inherited from this class.  The various identity values are supplied
  42 // by virtual functions.
  43 
  44 
  45 //=============================================================================
  46 //------------------------------hash-------------------------------------------
  47 // Hash function over AddNodes.  Needs to be commutative; i.e., I swap
  48 // (commute) inputs to AddNodes willy-nilly so the hash function must return
  49 // the same value in the presence of edge swapping.
  50 uint AddNode::hash() const {
  51   return (uintptr_t)in(1) + (uintptr_t)in(2) + Opcode();
  52 }
  53 
  54 //------------------------------Identity---------------------------------------
  55 // If either input is a constant 0, return the other input.
  56 Node* AddNode::Identity(PhaseGVN* phase) {
  57   const Type *zero = add_id();  // The additive identity
  58   if( phase->type( in(1) )->higher_equal( zero ) ) return in(2);
  59   if( phase->type( in(2) )->higher_equal( zero ) ) return in(1);
  60   return this;
  61 }
  62 
  63 //------------------------------commute----------------------------------------
  64 // Commute operands to move loads and constants to the right.
  65 static bool commute(PhaseGVN* phase, Node* add) {
  66   Node *in1 = add->in(1);
  67   Node *in2 = add->in(2);
  68 
  69   // convert "max(a,b) + min(a,b)" into "a+b".
  70   if ((in1->Opcode() == add->as_Add()->max_opcode() && in2->Opcode() == add->as_Add()->min_opcode())
  71       || (in1->Opcode() == add->as_Add()->min_opcode() && in2->Opcode() == add->as_Add()->max_opcode())) {
  72     Node *in11 = in1->in(1);
  73     Node *in12 = in1->in(2);
  74 
  75     Node *in21 = in2->in(1);
  76     Node *in22 = in2->in(2);
  77 
  78     if ((in11 == in21 && in12 == in22) ||
  79         (in11 == in22 && in12 == in21)) {
  80       add->set_req_X(1, in11, phase);
  81       add->set_req_X(2, in12, phase);
  82       return true;
  83     }
  84   }
  85 
  86   bool con_left = phase->type(in1)->singleton();
  87   bool con_right = phase->type(in2)->singleton();
  88 
  89   // Convert "1+x" into "x+1".
  90   // Right is a constant; leave it
  91   if( con_right ) return false;
  92   // Left is a constant; move it right.
  93   if( con_left ) {
  94     add->swap_edges(1, 2);
  95     return true;
  96   }
  97 
  98   // Convert "Load+x" into "x+Load".
  99   // Now check for loads
 100   if (in2->is_Load()) {
 101     if (!in1->is_Load()) {
 102       // already x+Load to return
 103       return false;
 104     }
 105     // both are loads, so fall through to sort inputs by idx
 106   } else if( in1->is_Load() ) {
 107     // Left is a Load and Right is not; move it right.
 108     add->swap_edges(1, 2);
 109     return true;
 110   }
 111 
 112   PhiNode *phi;
 113   // Check for tight loop increments: Loop-phi of Add of loop-phi
 114   if (in1->is_Phi() && (phi = in1->as_Phi()) && phi->region()->is_Loop() && phi->in(2) == add)
 115     return false;
 116   if (in2->is_Phi() && (phi = in2->as_Phi()) && phi->region()->is_Loop() && phi->in(2) == add) {
 117     add->swap_edges(1, 2);
 118     return true;
 119   }
 120 
 121   // Otherwise, sort inputs (commutativity) to help value numbering.
 122   if( in1->_idx > in2->_idx ) {
 123     add->swap_edges(1, 2);
 124     return true;
 125   }
 126   return false;
 127 }
 128 
 129 //------------------------------Idealize---------------------------------------
 130 // If we get here, we assume we are associative!
 131 Node *AddNode::Ideal(PhaseGVN *phase, bool can_reshape) {
 132   const Type *t1 = phase->type(in(1));
 133   const Type *t2 = phase->type(in(2));
 134   bool con_left  = t1->singleton();
 135   bool con_right = t2->singleton();
 136 
 137   // Check for commutative operation desired
 138   if (commute(phase, this)) return this;
 139 
 140   AddNode *progress = nullptr;             // Progress flag
 141 
 142   // Convert "(x+1)+2" into "x+(1+2)".  If the right input is a
 143   // constant, and the left input is an add of a constant, flatten the
 144   // expression tree.
 145   Node *add1 = in(1);
 146   Node *add2 = in(2);
 147   int add1_op = add1->Opcode();
 148   int this_op = Opcode();
 149   if (con_right && t2 != Type::TOP && // Right input is a constant?
 150       add1_op == this_op) { // Left input is an Add?
 151 
 152     // Type of left _in right input
 153     const Type *t12 = phase->type(add1->in(2));
 154     if (t12->singleton() && t12 != Type::TOP) { // Left input is an add of a constant?
 155       // Check for rare case of closed data cycle which can happen inside
 156       // unreachable loops. In these cases the computation is undefined.
 157 #ifdef ASSERT
 158       Node *add11    = add1->in(1);
 159       int   add11_op = add11->Opcode();
 160       if ((add1 == add1->in(1))
 161           || (add11_op == this_op && add11->in(1) == add1)) {
 162         assert(false, "dead loop in AddNode::Ideal");
 163       }
 164 #endif
 165       // The Add of the flattened expression
 166       Node *x1 = add1->in(1);
 167       Node *x2 = phase->makecon(add1->as_Add()->add_ring(t2, t12));
 168       set_req_X(2, x2, phase);
 169       set_req_X(1, x1, phase);
 170       progress = this;            // Made progress
 171       add1 = in(1);
 172       add1_op = add1->Opcode();
 173     }
 174   }
 175 
 176   // Convert "(x+1)+y" into "(x+y)+1".  Push constants down the expression tree.
 177   if (add1_op == this_op && !con_right) {
 178     Node *a12 = add1->in(2);
 179     const Type *t12 = phase->type( a12 );
 180     if (t12->singleton() && t12 != Type::TOP && (add1 != add1->in(1)) &&
 181         !(add1->in(1)->is_Phi() && (add1->in(1)->as_Phi()->is_tripcount(T_INT) || add1->in(1)->as_Phi()->is_tripcount(T_LONG)))) {
 182       assert(add1->in(1) != this, "dead loop in AddNode::Ideal");
 183       add2 = add1->clone();
 184       add2->set_req(2, in(2));
 185       add2 = phase->transform(add2);
 186       set_req_X(1, add2, phase);
 187       set_req_X(2, a12, phase);
 188       progress = this;
 189       add2 = a12;
 190     }
 191   }
 192 
 193   // Convert "x+(y+1)" into "(x+y)+1".  Push constants down the expression tree.
 194   int add2_op = add2->Opcode();
 195   if (add2_op == this_op && !con_left) {
 196     Node *a22 = add2->in(2);
 197     const Type *t22 = phase->type( a22 );
 198     if (t22->singleton() && t22 != Type::TOP && (add2 != add2->in(1)) &&
 199         !(add2->in(1)->is_Phi() && (add2->in(1)->as_Phi()->is_tripcount(T_INT) || add2->in(1)->as_Phi()->is_tripcount(T_LONG)))) {
 200       assert(add2->in(1) != this, "dead loop in AddNode::Ideal");
 201       Node *addx = add2->clone();
 202       addx->set_req(1, in(1));
 203       addx->set_req(2, add2->in(1));
 204       addx = phase->transform(addx);
 205       set_req_X(1, addx, phase);
 206       set_req_X(2, a22, phase);
 207       progress = this;
 208     }
 209   }
 210 
 211   return progress;
 212 }
 213 
 214 //------------------------------Value-----------------------------------------
 215 // An add node sums it's two _in.  If one input is an RSD, we must mixin
 216 // the other input's symbols.
 217 const Type* AddNode::Value(PhaseGVN* phase) const {
 218   // Either input is TOP ==> the result is TOP
 219   const Type* t1 = phase->type(in(1));
 220   const Type* t2 = phase->type(in(2));
 221   if (t1 == Type::TOP || t2 == Type::TOP) {
 222     return Type::TOP;
 223   }
 224 
 225   // Check for an addition involving the additive identity
 226   const Type* tadd = add_of_identity(t1, t2);
 227   if (tadd != nullptr) {
 228     return tadd;
 229   }
 230 
 231   return add_ring(t1, t2);               // Local flavor of type addition
 232 }
 233 
 234 //------------------------------add_identity-----------------------------------
 235 // Check for addition of the identity
 236 const Type *AddNode::add_of_identity( const Type *t1, const Type *t2 ) const {
 237   const Type *zero = add_id();  // The additive identity
 238   if( t1->higher_equal( zero ) ) return t2;
 239   if( t2->higher_equal( zero ) ) return t1;
 240 
 241   return nullptr;
 242 }
 243 
 244 AddNode* AddNode::make(Node* in1, Node* in2, BasicType bt) {
 245   switch (bt) {
 246     case T_INT:
 247       return new AddINode(in1, in2);
 248     case T_LONG:
 249       return new AddLNode(in1, in2);
 250     default:
 251       fatal("Not implemented for %s", type2name(bt));
 252   }
 253   return nullptr;
 254 }
 255 
 256 //=============================================================================
 257 //------------------------------Idealize---------------------------------------
 258 Node* AddNode::IdealIL(PhaseGVN* phase, bool can_reshape, BasicType bt) {
 259   Node* in1 = in(1);
 260   Node* in2 = in(2);
 261   int op1 = in1->Opcode();
 262   int op2 = in2->Opcode();
 263   // Fold (con1-x)+con2 into (con1+con2)-x
 264   if (op1 == Op_Add(bt) && op2 == Op_Sub(bt)) {
 265     // Swap edges to try optimizations below
 266     in1 = in2;
 267     in2 = in(1);
 268     op1 = op2;
 269     op2 = in2->Opcode();
 270   }
 271   if (op1 == Op_Sub(bt)) {
 272     const Type* t_sub1 = phase->type(in1->in(1));
 273     const Type* t_2    = phase->type(in2       );
 274     if (t_sub1->singleton() && t_2->singleton() && t_sub1 != Type::TOP && t_2 != Type::TOP) {
 275       return SubNode::make(phase->makecon(add_ring(t_sub1, t_2)), in1->in(2), bt);
 276     }
 277     // Convert "(a-b)+(c-d)" into "(a+c)-(b+d)"
 278     if (op2 == Op_Sub(bt)) {
 279       // Check for dead cycle: d = (a-b)+(c-d)
 280       assert( in1->in(2) != this && in2->in(2) != this,
 281               "dead loop in AddINode::Ideal" );
 282       Node* sub = SubNode::make(nullptr, nullptr, bt);
 283       Node* sub_in1;
 284       PhaseIterGVN* igvn = phase->is_IterGVN();
 285       // During IGVN, if both inputs of the new AddNode are a tree of SubNodes, this same transformation will be applied
 286       // to every node of the tree. Calling transform() causes the transformation to be applied recursively, once per
 287       // tree node whether some subtrees are identical or not. Pushing to the IGVN worklist instead, causes the transform
 288       // to be applied once per unique subtrees (because all uses of a subtree are updated with the result of the
 289       // transformation). In case of a large tree, this can make a difference in compilation time.
 290       if (igvn != nullptr) {
 291         sub_in1 = igvn->register_new_node_with_optimizer(AddNode::make(in1->in(1), in2->in(1), bt));
 292       } else {
 293         sub_in1 = phase->transform(AddNode::make(in1->in(1), in2->in(1), bt));
 294       }
 295       Node* sub_in2;
 296       if (igvn != nullptr) {
 297         sub_in2 = igvn->register_new_node_with_optimizer(AddNode::make(in1->in(2), in2->in(2), bt));
 298       } else {
 299         sub_in2 = phase->transform(AddNode::make(in1->in(2), in2->in(2), bt));
 300       }
 301       sub->init_req(1, sub_in1);
 302       sub->init_req(2, sub_in2);
 303       return sub;
 304     }
 305     // Convert "(a-b)+(b+c)" into "(a+c)"
 306     if (op2 == Op_Add(bt) && in1->in(2) == in2->in(1)) {
 307       assert(in1->in(1) != this && in2->in(2) != this,"dead loop in AddINode::Ideal/AddLNode::Ideal");
 308       return AddNode::make(in1->in(1), in2->in(2), bt);
 309     }
 310     // Convert "(a-b)+(c+b)" into "(a+c)"
 311     if (op2 == Op_Add(bt) && in1->in(2) == in2->in(2)) {
 312       assert(in1->in(1) != this && in2->in(1) != this,"dead loop in AddINode::Ideal/AddLNode::Ideal");
 313       return AddNode::make(in1->in(1), in2->in(1), bt);
 314     }
 315   }
 316 
 317   // Convert (con - y) + x into "(x - y) + con"
 318   if (op1 == Op_Sub(bt) && in1->in(1)->Opcode() == Op_ConIL(bt)
 319       && in1 != in1->in(2) && !(in1->in(2)->is_Phi() && in1->in(2)->as_Phi()->is_tripcount(bt))) {
 320     return AddNode::make(phase->transform(SubNode::make(in2, in1->in(2), bt)), in1->in(1), bt);
 321   }
 322 
 323   // Convert x + (con - y) into "(x - y) + con"
 324   if (op2 == Op_Sub(bt) && in2->in(1)->Opcode() == Op_ConIL(bt)
 325       && in2 != in2->in(2) && !(in2->in(2)->is_Phi() && in2->in(2)->as_Phi()->is_tripcount(bt))) {
 326     return AddNode::make(phase->transform(SubNode::make(in1, in2->in(2), bt)), in2->in(1), bt);
 327   }
 328 
 329   // Associative
 330   if (op1 == Op_Mul(bt) && op2 == Op_Mul(bt)) {
 331     Node* add_in1 = nullptr;
 332     Node* add_in2 = nullptr;
 333     Node* mul_in = nullptr;
 334 
 335     if (in1->in(1) == in2->in(1)) {
 336       // Convert "a*b+a*c into a*(b+c)
 337       add_in1 = in1->in(2);
 338       add_in2 = in2->in(2);
 339       mul_in = in1->in(1);
 340     } else if (in1->in(2) == in2->in(1)) {
 341       // Convert a*b+b*c into b*(a+c)
 342       add_in1 = in1->in(1);
 343       add_in2 = in2->in(2);
 344       mul_in = in1->in(2);
 345     } else if (in1->in(2) == in2->in(2)) {
 346       // Convert a*c+b*c into (a+b)*c
 347       add_in1 = in1->in(1);
 348       add_in2 = in2->in(1);
 349       mul_in = in1->in(2);
 350     } else if (in1->in(1) == in2->in(2)) {
 351       // Convert a*b+c*a into a*(b+c)
 352       add_in1 = in1->in(2);
 353       add_in2 = in2->in(1);
 354       mul_in = in1->in(1);
 355     }
 356 
 357     if (mul_in != nullptr) {
 358       Node* add = phase->transform(AddNode::make(add_in1, add_in2, bt));
 359       return MulNode::make(mul_in, add, bt);
 360     }
 361   }
 362 
 363   // Convert (x >>> rshift) + (x << lshift) into RotateRight(x, rshift)
 364   if (Matcher::match_rule_supported(Op_RotateRight) &&
 365       ((op1 == Op_URShift(bt) && op2 == Op_LShift(bt)) || (op1 == Op_LShift(bt) && op2 == Op_URShift(bt))) &&
 366       in1->in(1) != nullptr && in1->in(1) == in2->in(1)) {
 367     Node* rshift = op1 == Op_URShift(bt) ? in1->in(2) : in2->in(2);
 368     Node* lshift = op1 == Op_URShift(bt) ? in2->in(2) : in1->in(2);
 369     if (rshift != nullptr && lshift != nullptr) {
 370       const TypeInt* rshift_t = phase->type(rshift)->isa_int();
 371       const TypeInt* lshift_t = phase->type(lshift)->isa_int();
 372       int bits = bt == T_INT ? 32 : 64;
 373       int mask = bt == T_INT ? 0x1F : 0x3F;
 374       if (lshift_t != nullptr && lshift_t->is_con() &&
 375           rshift_t != nullptr && rshift_t->is_con() &&
 376           ((lshift_t->get_con() & mask) == (bits - (rshift_t->get_con() & mask)))) {
 377         return new RotateRightNode(in1->in(1), phase->intcon(rshift_t->get_con() & mask), TypeInteger::bottom(bt));
 378       }
 379     }
 380   }
 381 
 382   return AddNode::Ideal(phase, can_reshape);
 383 }
 384 
 385 
 386 Node* AddINode::Ideal(PhaseGVN* phase, bool can_reshape) {
 387   Node* in1 = in(1);
 388   Node* in2 = in(2);
 389   int op1 = in1->Opcode();
 390   int op2 = in2->Opcode();
 391 
 392   // Convert (x>>>z)+y into (x+(y<<z))>>>z for small constant z and y.
 393   // Helps with array allocation math constant folding
 394   // See 4790063:
 395   // Unrestricted transformation is unsafe for some runtime values of 'x'
 396   // ( x ==  0, z == 1, y == -1 ) fails
 397   // ( x == -5, z == 1, y ==  1 ) fails
 398   // Transform works for small z and small negative y when the addition
 399   // (x + (y << z)) does not cross zero.
 400   // Implement support for negative y and (x >= -(y << z))
 401   // Have not observed cases where type information exists to support
 402   // positive y and (x <= -(y << z))
 403   if (op1 == Op_URShiftI && op2 == Op_ConI &&
 404       in1->in(2)->Opcode() == Op_ConI) {
 405     jint z = phase->type(in1->in(2))->is_int()->get_con() & 0x1f; // only least significant 5 bits matter
 406     jint y = phase->type(in2)->is_int()->get_con();
 407 
 408     if (z < 5 && -5 < y && y < 0) {
 409       const Type* t_in11 = phase->type(in1->in(1));
 410       if( t_in11 != Type::TOP && (t_in11->is_int()->_lo >= -(y << z))) {
 411         Node* a = phase->transform(new AddINode( in1->in(1), phase->intcon(y<<z)));
 412         return new URShiftINode(a, in1->in(2));
 413       }
 414     }
 415   }
 416 
 417   return AddNode::IdealIL(phase, can_reshape, T_INT);
 418 }
 419 
 420 
 421 //------------------------------Identity---------------------------------------
 422 // Fold (x-y)+y  OR  y+(x-y)  into  x
 423 Node* AddINode::Identity(PhaseGVN* phase) {
 424   if (in(1)->Opcode() == Op_SubI && in(1)->in(2) == in(2)) {
 425     return in(1)->in(1);
 426   } else if (in(2)->Opcode() == Op_SubI && in(2)->in(2) == in(1)) {
 427     return in(2)->in(1);
 428   }
 429   return AddNode::Identity(phase);
 430 }
 431 
 432 
 433 //------------------------------add_ring---------------------------------------
 434 // Supplied function returns the sum of the inputs.  Guaranteed never
 435 // to be passed a TOP or BOTTOM type, these are filtered out by
 436 // pre-check.
 437 const Type *AddINode::add_ring( const Type *t0, const Type *t1 ) const {
 438   const TypeInt *r0 = t0->is_int(); // Handy access
 439   const TypeInt *r1 = t1->is_int();
 440   int lo = java_add(r0->_lo, r1->_lo);
 441   int hi = java_add(r0->_hi, r1->_hi);
 442   if( !(r0->is_con() && r1->is_con()) ) {
 443     // Not both constants, compute approximate result
 444     if( (r0->_lo & r1->_lo) < 0 && lo >= 0 ) {
 445       lo = min_jint; hi = max_jint; // Underflow on the low side
 446     }
 447     if( (~(r0->_hi | r1->_hi)) < 0 && hi < 0 ) {
 448       lo = min_jint; hi = max_jint; // Overflow on the high side
 449     }
 450     if( lo > hi ) {               // Handle overflow
 451       lo = min_jint; hi = max_jint;
 452     }
 453   } else {
 454     // both constants, compute precise result using 'lo' and 'hi'
 455     // Semantics define overflow and underflow for integer addition
 456     // as expected.  In particular: 0x80000000 + 0x80000000 --> 0x0
 457   }
 458   return TypeInt::make( lo, hi, MAX2(r0->_widen,r1->_widen) );
 459 }
 460 
 461 
 462 //=============================================================================
 463 //------------------------------Idealize---------------------------------------
 464 Node* AddLNode::Ideal(PhaseGVN* phase, bool can_reshape) {
 465   return AddNode::IdealIL(phase, can_reshape, T_LONG);
 466 }
 467 
 468 
 469 //------------------------------Identity---------------------------------------
 470 // Fold (x-y)+y  OR  y+(x-y)  into  x
 471 Node* AddLNode::Identity(PhaseGVN* phase) {
 472   if (in(1)->Opcode() == Op_SubL && in(1)->in(2) == in(2)) {
 473     return in(1)->in(1);
 474   } else if (in(2)->Opcode() == Op_SubL && in(2)->in(2) == in(1)) {
 475     return in(2)->in(1);
 476   }
 477   return AddNode::Identity(phase);
 478 }
 479 
 480 
 481 //------------------------------add_ring---------------------------------------
 482 // Supplied function returns the sum of the inputs.  Guaranteed never
 483 // to be passed a TOP or BOTTOM type, these are filtered out by
 484 // pre-check.
 485 const Type *AddLNode::add_ring( const Type *t0, const Type *t1 ) const {
 486   const TypeLong *r0 = t0->is_long(); // Handy access
 487   const TypeLong *r1 = t1->is_long();
 488   jlong lo = java_add(r0->_lo, r1->_lo);
 489   jlong hi = java_add(r0->_hi, r1->_hi);
 490   if( !(r0->is_con() && r1->is_con()) ) {
 491     // Not both constants, compute approximate result
 492     if( (r0->_lo & r1->_lo) < 0 && lo >= 0 ) {
 493       lo =min_jlong; hi = max_jlong; // Underflow on the low side
 494     }
 495     if( (~(r0->_hi | r1->_hi)) < 0 && hi < 0 ) {
 496       lo = min_jlong; hi = max_jlong; // Overflow on the high side
 497     }
 498     if( lo > hi ) {               // Handle overflow
 499       lo = min_jlong; hi = max_jlong;
 500     }
 501   } else {
 502     // both constants, compute precise result using 'lo' and 'hi'
 503     // Semantics define overflow and underflow for integer addition
 504     // as expected.  In particular: 0x80000000 + 0x80000000 --> 0x0
 505   }
 506   return TypeLong::make( lo, hi, MAX2(r0->_widen,r1->_widen) );
 507 }
 508 
 509 
 510 //=============================================================================
 511 //------------------------------add_of_identity--------------------------------
 512 // Check for addition of the identity
 513 const Type *AddFNode::add_of_identity( const Type *t1, const Type *t2 ) const {
 514   // x ADD 0  should return x unless 'x' is a -zero
 515   //
 516   // const Type *zero = add_id();     // The additive identity
 517   // jfloat f1 = t1->getf();
 518   // jfloat f2 = t2->getf();
 519   //
 520   // if( t1->higher_equal( zero ) ) return t2;
 521   // if( t2->higher_equal( zero ) ) return t1;
 522 
 523   return nullptr;
 524 }
 525 
 526 //------------------------------add_ring---------------------------------------
 527 // Supplied function returns the sum of the inputs.
 528 // This also type-checks the inputs for sanity.  Guaranteed never to
 529 // be passed a TOP or BOTTOM type, these are filtered out by pre-check.
 530 const Type *AddFNode::add_ring( const Type *t0, const Type *t1 ) const {
 531   if (!t0->isa_float_constant() || !t1->isa_float_constant()) {
 532     return bottom_type();
 533   }
 534   return TypeF::make( t0->getf() + t1->getf() );
 535 }
 536 
 537 //------------------------------Ideal------------------------------------------
 538 Node *AddFNode::Ideal(PhaseGVN *phase, bool can_reshape) {
 539   // Floating point additions are not associative because of boundary conditions (infinity)
 540   return commute(phase, this) ? this : nullptr;
 541 }
 542 
 543 
 544 //=============================================================================
 545 //------------------------------add_of_identity--------------------------------
 546 // Check for addition of the identity
 547 const Type *AddDNode::add_of_identity( const Type *t1, const Type *t2 ) const {
 548   // x ADD 0  should return x unless 'x' is a -zero
 549   //
 550   // const Type *zero = add_id();     // The additive identity
 551   // jfloat f1 = t1->getf();
 552   // jfloat f2 = t2->getf();
 553   //
 554   // if( t1->higher_equal( zero ) ) return t2;
 555   // if( t2->higher_equal( zero ) ) return t1;
 556 
 557   return nullptr;
 558 }
 559 //------------------------------add_ring---------------------------------------
 560 // Supplied function returns the sum of the inputs.
 561 // This also type-checks the inputs for sanity.  Guaranteed never to
 562 // be passed a TOP or BOTTOM type, these are filtered out by pre-check.
 563 const Type *AddDNode::add_ring( const Type *t0, const Type *t1 ) const {
 564   if (!t0->isa_double_constant() || !t1->isa_double_constant()) {
 565     return bottom_type();
 566   }
 567   return TypeD::make( t0->getd() + t1->getd() );
 568 }
 569 
 570 //------------------------------Ideal------------------------------------------
 571 Node *AddDNode::Ideal(PhaseGVN *phase, bool can_reshape) {
 572   // Floating point additions are not associative because of boundary conditions (infinity)
 573   return commute(phase, this) ? this : nullptr;
 574 }
 575 
 576 
 577 //=============================================================================
 578 //------------------------------Identity---------------------------------------
 579 // If one input is a constant 0, return the other input.
 580 Node* AddPNode::Identity(PhaseGVN* phase) {
 581   return ( phase->type( in(Offset) )->higher_equal( TypeX_ZERO ) ) ? in(Address) : this;
 582 }
 583 
 584 //------------------------------Idealize---------------------------------------
 585 Node *AddPNode::Ideal(PhaseGVN *phase, bool can_reshape) {
 586   // Bail out if dead inputs
 587   if( phase->type( in(Address) ) == Type::TOP ) return nullptr;
 588 
 589   // If the left input is an add of a constant, flatten the expression tree.
 590   const Node *n = in(Address);
 591   if (n->is_AddP() && n->in(Base) == in(Base)) {
 592     const AddPNode *addp = n->as_AddP(); // Left input is an AddP
 593     assert( !addp->in(Address)->is_AddP() ||
 594              addp->in(Address)->as_AddP() != addp,
 595             "dead loop in AddPNode::Ideal" );
 596     // Type of left input's right input
 597     const Type *t = phase->type( addp->in(Offset) );
 598     if( t == Type::TOP ) return nullptr;
 599     const TypeX *t12 = t->is_intptr_t();
 600     if( t12->is_con() ) {       // Left input is an add of a constant?
 601       // If the right input is a constant, combine constants
 602       const Type *temp_t2 = phase->type( in(Offset) );
 603       if( temp_t2 == Type::TOP ) return nullptr;
 604       const TypeX *t2 = temp_t2->is_intptr_t();
 605       Node* address;
 606       Node* offset;
 607       if( t2->is_con() ) {
 608         // The Add of the flattened expression
 609         address = addp->in(Address);
 610         offset  = phase->MakeConX(t2->get_con() + t12->get_con());
 611       } else {
 612         // Else move the constant to the right.  ((A+con)+B) into ((A+B)+con)
 613         address = phase->transform(new AddPNode(in(Base),addp->in(Address),in(Offset)));
 614         offset  = addp->in(Offset);
 615       }
 616       set_req_X(Address, address, phase);
 617       set_req_X(Offset, offset, phase);
 618       return this;
 619     }
 620   }
 621 
 622   // Raw pointers?
 623   if( in(Base)->bottom_type() == Type::TOP ) {
 624     // If this is a null+long form (from unsafe accesses), switch to a rawptr.
 625     if (phase->type(in(Address)) == TypePtr::NULL_PTR) {
 626       Node* offset = in(Offset);
 627       return new CastX2PNode(offset);
 628     }
 629   }
 630 
 631   // If the right is an add of a constant, push the offset down.
 632   // Convert: (ptr + (offset+con)) into (ptr+offset)+con.
 633   // The idea is to merge array_base+scaled_index groups together,
 634   // and only have different constant offsets from the same base.
 635   const Node *add = in(Offset);
 636   if( add->Opcode() == Op_AddX && add->in(1) != add ) {
 637     const Type *t22 = phase->type( add->in(2) );
 638     if( t22->singleton() && (t22 != Type::TOP) ) {  // Right input is an add of a constant?
 639       set_req(Address, phase->transform(new AddPNode(in(Base),in(Address),add->in(1))));
 640       set_req_X(Offset, add->in(2), phase); // puts add on igvn worklist if needed
 641       return this;              // Made progress
 642     }
 643   }
 644 
 645   return nullptr;                  // No progress
 646 }
 647 
 648 //------------------------------bottom_type------------------------------------
 649 // Bottom-type is the pointer-type with unknown offset.
 650 const Type *AddPNode::bottom_type() const {
 651   if (in(Address) == nullptr)  return TypePtr::BOTTOM;
 652   const TypePtr *tp = in(Address)->bottom_type()->isa_ptr();
 653   if( !tp ) return Type::TOP;   // TOP input means TOP output
 654   assert( in(Offset)->Opcode() != Op_ConP, "" );
 655   const Type *t = in(Offset)->bottom_type();
 656   if( t == Type::TOP )
 657     return tp->add_offset(Type::OffsetTop);
 658   const TypeX *tx = t->is_intptr_t();
 659   intptr_t txoffset = Type::OffsetBot;
 660   if (tx->is_con()) {   // Left input is an add of a constant?
 661     txoffset = tx->get_con();
 662   }
 663   return tp->add_offset(txoffset);
 664 }
 665 
 666 //------------------------------Value------------------------------------------
 667 const Type* AddPNode::Value(PhaseGVN* phase) const {
 668   // Either input is TOP ==> the result is TOP
 669   const Type *t1 = phase->type( in(Address) );
 670   const Type *t2 = phase->type( in(Offset) );
 671   if( t1 == Type::TOP ) return Type::TOP;
 672   if( t2 == Type::TOP ) return Type::TOP;
 673 
 674   // Left input is a pointer
 675   const TypePtr *p1 = t1->isa_ptr();
 676   // Right input is an int
 677   const TypeX *p2 = t2->is_intptr_t();
 678   // Add 'em
 679   intptr_t p2offset = Type::OffsetBot;
 680   if (p2->is_con()) {   // Left input is an add of a constant?
 681     p2offset = p2->get_con();
 682   }
 683   return p1->add_offset(p2offset);
 684 }
 685 
 686 //------------------------Ideal_base_and_offset--------------------------------
 687 // Split an oop pointer into a base and offset.
 688 // (The offset might be Type::OffsetBot in the case of an array.)
 689 // Return the base, or null if failure.
 690 Node* AddPNode::Ideal_base_and_offset(Node* ptr, PhaseValues* phase,
 691                                       // second return value:
 692                                       intptr_t& offset) {
 693   if (ptr->is_AddP()) {
 694     Node* base = ptr->in(AddPNode::Base);
 695     Node* addr = ptr->in(AddPNode::Address);
 696     Node* offs = ptr->in(AddPNode::Offset);
 697     if (base == addr || base->is_top()) {
 698       offset = phase->find_intptr_t_con(offs, Type::OffsetBot);
 699       if (offset != Type::OffsetBot) {
 700         return addr;
 701       }
 702     }
 703   }
 704   offset = Type::OffsetBot;
 705   return nullptr;
 706 }
 707 
 708 //------------------------------unpack_offsets----------------------------------
 709 // Collect the AddP offset values into the elements array, giving up
 710 // if there are more than length.
 711 int AddPNode::unpack_offsets(Node* elements[], int length) {
 712   int count = 0;
 713   Node* addr = this;
 714   Node* base = addr->in(AddPNode::Base);
 715   while (addr->is_AddP()) {
 716     if (addr->in(AddPNode::Base) != base) {
 717       // give up
 718       return -1;
 719     }
 720     elements[count++] = addr->in(AddPNode::Offset);
 721     if (count == length) {
 722       // give up
 723       return -1;
 724     }
 725     addr = addr->in(AddPNode::Address);
 726   }
 727   if (addr != base) {
 728     return -1;
 729   }
 730   return count;
 731 }
 732 
 733 //------------------------------match_edge-------------------------------------
 734 // Do we Match on this edge index or not?  Do not match base pointer edge
 735 uint AddPNode::match_edge(uint idx) const {
 736   return idx > Base;
 737 }
 738 
 739 //=============================================================================
 740 //------------------------------Identity---------------------------------------
 741 Node* OrINode::Identity(PhaseGVN* phase) {
 742   // x | x => x
 743   if (in(1) == in(2)) {
 744     return in(1);
 745   }
 746 
 747   return AddNode::Identity(phase);
 748 }
 749 
 750 // Find shift value for Integer or Long OR.
 751 Node* rotate_shift(PhaseGVN* phase, Node* lshift, Node* rshift, int mask) {
 752   // val << norm_con_shift | val >> ({32|64} - norm_con_shift) => rotate_left val, norm_con_shift
 753   const TypeInt* lshift_t = phase->type(lshift)->isa_int();
 754   const TypeInt* rshift_t = phase->type(rshift)->isa_int();
 755   if (lshift_t != nullptr && lshift_t->is_con() &&
 756       rshift_t != nullptr && rshift_t->is_con() &&
 757       ((lshift_t->get_con() & mask) == ((mask + 1) - (rshift_t->get_con() & mask)))) {
 758     return phase->intcon(lshift_t->get_con() & mask);
 759   }
 760   // val << var_shift | val >> ({0|32|64} - var_shift) => rotate_left val, var_shift
 761   if (rshift->Opcode() == Op_SubI && rshift->in(2) == lshift && rshift->in(1)->is_Con()){
 762     const TypeInt* shift_t = phase->type(rshift->in(1))->isa_int();
 763     if (shift_t != nullptr && shift_t->is_con() &&
 764         (shift_t->get_con() == 0 || shift_t->get_con() == (mask + 1))) {
 765       return lshift;
 766     }
 767   }
 768   return nullptr;
 769 }
 770 
 771 Node* OrINode::Ideal(PhaseGVN* phase, bool can_reshape) {
 772   int lopcode = in(1)->Opcode();
 773   int ropcode = in(2)->Opcode();
 774   if (Matcher::match_rule_supported(Op_RotateLeft) &&
 775       lopcode == Op_LShiftI && ropcode == Op_URShiftI && in(1)->in(1) == in(2)->in(1)) {
 776     Node* lshift = in(1)->in(2);
 777     Node* rshift = in(2)->in(2);
 778     Node* shift = rotate_shift(phase, lshift, rshift, 0x1F);
 779     if (shift != nullptr) {
 780       return new RotateLeftNode(in(1)->in(1), shift, TypeInt::INT);
 781     }
 782     return nullptr;
 783   }
 784   if (Matcher::match_rule_supported(Op_RotateRight) &&
 785       lopcode == Op_URShiftI && ropcode == Op_LShiftI && in(1)->in(1) == in(2)->in(1)) {
 786     Node* rshift = in(1)->in(2);
 787     Node* lshift = in(2)->in(2);
 788     Node* shift = rotate_shift(phase, rshift, lshift, 0x1F);
 789     if (shift != nullptr) {
 790       return new RotateRightNode(in(1)->in(1), shift, TypeInt::INT);
 791     }
 792   }
 793   return nullptr;
 794 }
 795 
 796 //------------------------------add_ring---------------------------------------
 797 // Supplied function returns the sum of the inputs IN THE CURRENT RING.  For
 798 // the logical operations the ring's ADD is really a logical OR function.
 799 // This also type-checks the inputs for sanity.  Guaranteed never to
 800 // be passed a TOP or BOTTOM type, these are filtered out by pre-check.
 801 const Type *OrINode::add_ring( const Type *t0, const Type *t1 ) const {
 802   const TypeInt *r0 = t0->is_int(); // Handy access
 803   const TypeInt *r1 = t1->is_int();
 804 
 805   // If both args are bool, can figure out better types
 806   if ( r0 == TypeInt::BOOL ) {
 807     if ( r1 == TypeInt::ONE) {
 808       return TypeInt::ONE;
 809     } else if ( r1 == TypeInt::BOOL ) {
 810       return TypeInt::BOOL;
 811     }
 812   } else if ( r0 == TypeInt::ONE ) {
 813     if ( r1 == TypeInt::BOOL ) {
 814       return TypeInt::ONE;
 815     }
 816   }
 817 
 818   // If either input is not a constant, just return all integers.
 819   if( !r0->is_con() || !r1->is_con() )
 820     return TypeInt::INT;        // Any integer, but still no symbols.
 821 
 822   // Otherwise just OR them bits.
 823   return TypeInt::make( r0->get_con() | r1->get_con() );
 824 }
 825 
 826 //=============================================================================
 827 //------------------------------Identity---------------------------------------
 828 Node* OrLNode::Identity(PhaseGVN* phase) {
 829   // x | x => x
 830   if (in(1) == in(2)) {
 831     return in(1);
 832   }
 833 
 834   return AddNode::Identity(phase);
 835 }
 836 
 837 Node* OrLNode::Ideal(PhaseGVN* phase, bool can_reshape) {
 838   int lopcode = in(1)->Opcode();
 839   int ropcode = in(2)->Opcode();
 840   if (Matcher::match_rule_supported(Op_RotateLeft) &&
 841       lopcode == Op_LShiftL && ropcode == Op_URShiftL && in(1)->in(1) == in(2)->in(1)) {
 842     Node* lshift = in(1)->in(2);
 843     Node* rshift = in(2)->in(2);
 844     Node* shift = rotate_shift(phase, lshift, rshift, 0x3F);
 845     if (shift != nullptr) {
 846       return new RotateLeftNode(in(1)->in(1), shift, TypeLong::LONG);
 847     }
 848     return nullptr;
 849   }
 850   if (Matcher::match_rule_supported(Op_RotateRight) &&
 851       lopcode == Op_URShiftL && ropcode == Op_LShiftL && in(1)->in(1) == in(2)->in(1)) {
 852     Node* rshift = in(1)->in(2);
 853     Node* lshift = in(2)->in(2);
 854     Node* shift = rotate_shift(phase, rshift, lshift, 0x3F);
 855     if (shift != nullptr) {
 856       return new RotateRightNode(in(1)->in(1), shift, TypeLong::LONG);
 857     }
 858   }
 859   return nullptr;
 860 }
 861 
 862 //------------------------------add_ring---------------------------------------
 863 const Type *OrLNode::add_ring( const Type *t0, const Type *t1 ) const {
 864   const TypeLong *r0 = t0->is_long(); // Handy access
 865   const TypeLong *r1 = t1->is_long();
 866 
 867   // If either input is not a constant, just return all integers.
 868   if( !r0->is_con() || !r1->is_con() )
 869     return TypeLong::LONG;      // Any integer, but still no symbols.
 870 
 871   // Otherwise just OR them bits.
 872   return TypeLong::make( r0->get_con() | r1->get_con() );
 873 }
 874 
 875 //---------------------------Helper -------------------------------------------
 876 /* Decide if the given node is used only in arithmetic expressions(add or sub).
 877  */
 878 static bool is_used_in_only_arithmetic(Node* n, BasicType bt) {
 879   for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
 880     Node* u = n->fast_out(i);
 881     if (u->Opcode() != Op_Add(bt) && u->Opcode() != Op_Sub(bt)) {
 882       return false;
 883     }
 884   }
 885   return true;
 886 }
 887 
 888 //=============================================================================
 889 //------------------------------Idealize---------------------------------------
 890 Node* XorINode::Ideal(PhaseGVN* phase, bool can_reshape) {
 891   Node* in1 = in(1);
 892   Node* in2 = in(2);
 893 
 894   // Convert ~x into -1-x when ~x is used in an arithmetic expression
 895   // or x itself is an expression.
 896   if (phase->type(in2) == TypeInt::MINUS_1) { // follows LHS^(-1), i.e., ~LHS
 897     if (phase->is_IterGVN()) {
 898       if (is_used_in_only_arithmetic(this, T_INT)
 899           // LHS is arithmetic
 900           || (in1->Opcode() == Op_AddI || in1->Opcode() == Op_SubI)) {
 901         return new SubINode(in2, in1);
 902       }
 903     } else {
 904       // graph could be incomplete in GVN so we postpone to IGVN
 905       phase->record_for_igvn(this);
 906     }
 907   }
 908 
 909   // Propagate xor through constant cmoves. This pattern can occur after expansion of Conv2B nodes.
 910   const TypeInt* in2_type = phase->type(in2)->isa_int();
 911   if (in1->Opcode() == Op_CMoveI && in2_type != nullptr && in2_type->is_con()) {
 912     int in2_val = in2_type->get_con();
 913 
 914     // Get types of both sides of the CMove
 915     const TypeInt* left = phase->type(in1->in(CMoveNode::IfFalse))->isa_int();
 916     const TypeInt* right = phase->type(in1->in(CMoveNode::IfTrue))->isa_int();
 917 
 918     // Ensure that both sides are int constants
 919     if (left != nullptr && right != nullptr && left->is_con() && right->is_con()) {
 920       Node* cond = in1->in(CMoveNode::Condition);
 921 
 922       // Check that the comparison is a bool and that the cmp node type is correct
 923       if (cond->is_Bool()) {
 924         int cmp_op = cond->in(1)->Opcode();
 925 
 926         if (cmp_op == Op_CmpI || cmp_op == Op_CmpP) {
 927           int l_val = left->get_con();
 928           int r_val = right->get_con();
 929 
 930           return new CMoveINode(cond, phase->intcon(l_val ^ in2_val), phase->intcon(r_val ^ in2_val), TypeInt::INT);
 931         }
 932       }
 933     }
 934   }
 935 
 936   return AddNode::Ideal(phase, can_reshape);
 937 }
 938 
 939 const Type* XorINode::Value(PhaseGVN* phase) const {
 940   Node* in1 = in(1);
 941   Node* in2 = in(2);
 942   const Type* t1 = phase->type(in1);
 943   const Type* t2 = phase->type(in2);
 944   if (t1 == Type::TOP || t2 == Type::TOP) {
 945     return Type::TOP;
 946   }
 947   // x ^ x ==> 0
 948   if (in1->eqv_uncast(in2)) {
 949     return add_id();
 950   }
 951   // result of xor can only have bits sets where any of the
 952   // inputs have bits set. lo can always become 0.
 953   const TypeInt* t1i = t1->is_int();
 954   const TypeInt* t2i = t2->is_int();
 955   if ((t1i->_lo >= 0) &&
 956       (t1i->_hi > 0)  &&
 957       (t2i->_lo >= 0) &&
 958       (t2i->_hi > 0)) {
 959     // hi - set all bits below the highest bit. Using round_down to avoid overflow.
 960     const TypeInt* t1x = TypeInt::make(0, round_down_power_of_2(t1i->_hi) + (round_down_power_of_2(t1i->_hi) - 1), t1i->_widen);
 961     const TypeInt* t2x = TypeInt::make(0, round_down_power_of_2(t2i->_hi) + (round_down_power_of_2(t2i->_hi) - 1), t2i->_widen);
 962     return t1x->meet(t2x);
 963   }
 964   return AddNode::Value(phase);
 965 }
 966 
 967 
 968 //------------------------------add_ring---------------------------------------
 969 // Supplied function returns the sum of the inputs IN THE CURRENT RING.  For
 970 // the logical operations the ring's ADD is really a logical OR function.
 971 // This also type-checks the inputs for sanity.  Guaranteed never to
 972 // be passed a TOP or BOTTOM type, these are filtered out by pre-check.
 973 const Type *XorINode::add_ring( const Type *t0, const Type *t1 ) const {
 974   const TypeInt *r0 = t0->is_int(); // Handy access
 975   const TypeInt *r1 = t1->is_int();
 976 
 977   // Complementing a boolean?
 978   if( r0 == TypeInt::BOOL && ( r1 == TypeInt::ONE
 979                                || r1 == TypeInt::BOOL))
 980     return TypeInt::BOOL;
 981 
 982   if( !r0->is_con() || !r1->is_con() ) // Not constants
 983     return TypeInt::INT;        // Any integer, but still no symbols.
 984 
 985   // Otherwise just XOR them bits.
 986   return TypeInt::make( r0->get_con() ^ r1->get_con() );
 987 }
 988 
 989 //=============================================================================
 990 //------------------------------add_ring---------------------------------------
 991 const Type *XorLNode::add_ring( const Type *t0, const Type *t1 ) const {
 992   const TypeLong *r0 = t0->is_long(); // Handy access
 993   const TypeLong *r1 = t1->is_long();
 994 
 995   // If either input is not a constant, just return all integers.
 996   if( !r0->is_con() || !r1->is_con() )
 997     return TypeLong::LONG;      // Any integer, but still no symbols.
 998 
 999   // Otherwise just OR them bits.
1000   return TypeLong::make( r0->get_con() ^ r1->get_con() );
1001 }
1002 
1003 Node* XorLNode::Ideal(PhaseGVN* phase, bool can_reshape) {
1004   Node* in1 = in(1);
1005   Node* in2 = in(2);
1006 
1007   // Convert ~x into -1-x when ~x is used in an arithmetic expression
1008   // or x itself is an arithmetic expression.
1009   if (phase->type(in2) == TypeLong::MINUS_1) { // follows LHS^(-1), i.e., ~LHS
1010     if (phase->is_IterGVN()) {
1011       if (is_used_in_only_arithmetic(this, T_LONG)
1012           // LHS is arithmetic
1013           || (in1->Opcode() == Op_AddL || in1->Opcode() == Op_SubL)) {
1014         return new SubLNode(in2, in1);
1015       }
1016     } else {
1017       // graph could be incomplete in GVN so we postpone to IGVN
1018       phase->record_for_igvn(this);
1019     }
1020   }
1021   return AddNode::Ideal(phase, can_reshape);
1022 }
1023 
1024 const Type* XorLNode::Value(PhaseGVN* phase) const {
1025   Node* in1 = in(1);
1026   Node* in2 = in(2);
1027   const Type* t1 = phase->type(in1);
1028   const Type* t2 = phase->type(in2);
1029   if (t1 == Type::TOP || t2 == Type::TOP) {
1030     return Type::TOP;
1031   }
1032   // x ^ x ==> 0
1033   if (in1->eqv_uncast(in2)) {
1034     return add_id();
1035   }
1036   // result of xor can only have bits sets where any of the
1037   // inputs have bits set. lo can always become 0.
1038   const TypeLong* t1l = t1->is_long();
1039   const TypeLong* t2l = t2->is_long();
1040   if ((t1l->_lo >= 0) &&
1041       (t1l->_hi > 0)  &&
1042       (t2l->_lo >= 0) &&
1043       (t2l->_hi > 0)) {
1044     // hi - set all bits below the highest bit. Using round_down to avoid overflow.
1045     const TypeLong* t1x = TypeLong::make(0, round_down_power_of_2(t1l->_hi) + (round_down_power_of_2(t1l->_hi) - 1), t1l->_widen);
1046     const TypeLong* t2x = TypeLong::make(0, round_down_power_of_2(t2l->_hi) + (round_down_power_of_2(t2l->_hi) - 1), t2l->_widen);
1047     return t1x->meet(t2x);
1048   }
1049   return AddNode::Value(phase);
1050 }
1051 
1052 Node* build_min_max_int(Node* a, Node* b, bool is_max) {
1053   if (is_max) {
1054     return new MaxINode(a, b);
1055   } else {
1056     return new MinINode(a, b);
1057   }
1058 }
1059 
1060 Node* MaxNode::build_min_max(Node* a, Node* b, bool is_max, bool is_unsigned, const Type* t, PhaseGVN& gvn) {
1061   bool is_int = gvn.type(a)->isa_int();
1062   assert(is_int || gvn.type(a)->isa_long(), "int or long inputs");
1063   assert(is_int == (gvn.type(b)->isa_int() != nullptr), "inconsistent inputs");
1064   BasicType bt = is_int ? T_INT: T_LONG;
1065   Node* hook = nullptr;
1066   if (gvn.is_IterGVN()) {
1067     // Make sure a and b are not destroyed
1068     hook = new Node(2);
1069     hook->init_req(0, a);
1070     hook->init_req(1, b);
1071   }
1072   Node* res = nullptr;
1073   if (is_int && !is_unsigned) {
1074     res = gvn.transform(build_min_max_int(a, b, is_max));
1075     assert(gvn.type(res)->is_int()->_lo >= t->is_int()->_lo && gvn.type(res)->is_int()->_hi <= t->is_int()->_hi, "type doesn't match");
1076   } else {
1077     Node* cmp = nullptr;
1078     if (is_max) {
1079       cmp = gvn.transform(CmpNode::make(a, b, bt, is_unsigned));
1080     } else {
1081       cmp = gvn.transform(CmpNode::make(b, a, bt, is_unsigned));
1082     }
1083     Node* bol = gvn.transform(new BoolNode(cmp, BoolTest::lt));
1084     res = gvn.transform(CMoveNode::make(nullptr, bol, a, b, t));
1085   }
1086   if (hook != nullptr) {
1087     hook->destruct(&gvn);
1088   }
1089   return res;
1090 }
1091 
1092 Node* MaxNode::build_min_max_diff_with_zero(Node* a, Node* b, bool is_max, const Type* t, PhaseGVN& gvn) {
1093   bool is_int = gvn.type(a)->isa_int();
1094   assert(is_int || gvn.type(a)->isa_long(), "int or long inputs");
1095   assert(is_int == (gvn.type(b)->isa_int() != nullptr), "inconsistent inputs");
1096   BasicType bt = is_int ? T_INT: T_LONG;
1097   Node* zero = gvn.integercon(0, bt);
1098   Node* hook = nullptr;
1099   if (gvn.is_IterGVN()) {
1100     // Make sure a and b are not destroyed
1101     hook = new Node(2);
1102     hook->init_req(0, a);
1103     hook->init_req(1, b);
1104   }
1105   Node* cmp = nullptr;
1106   if (is_max) {
1107     cmp = gvn.transform(CmpNode::make(a, b, bt, false));
1108   } else {
1109     cmp = gvn.transform(CmpNode::make(b, a, bt, false));
1110   }
1111   Node* sub = gvn.transform(SubNode::make(a, b, bt));
1112   Node* bol = gvn.transform(new BoolNode(cmp, BoolTest::lt));
1113   Node* res = gvn.transform(CMoveNode::make(nullptr, bol, sub, zero, t));
1114   if (hook != nullptr) {
1115     hook->destruct(&gvn);
1116   }
1117   return res;
1118 }
1119 
1120 // Check if addition of an integer with type 't' and a constant 'c' can overflow.
1121 static bool can_overflow(const TypeInt* t, jint c) {
1122   jint t_lo = t->_lo;
1123   jint t_hi = t->_hi;
1124   return ((c < 0 && (java_add(t_lo, c) > t_lo)) ||
1125           (c > 0 && (java_add(t_hi, c) < t_hi)));
1126 }
1127 
1128 // Let <x, x_off> = x_operands and <y, y_off> = y_operands.
1129 // If x == y and neither add(x, x_off) nor add(y, y_off) overflow, return
1130 // add(x, op(x_off, y_off)). Otherwise, return nullptr.
1131 Node* MaxNode::extract_add(PhaseGVN* phase, ConstAddOperands x_operands, ConstAddOperands y_operands) {
1132   Node* x = x_operands.first;
1133   Node* y = y_operands.first;
1134   int opcode = Opcode();
1135   assert(opcode == Op_MaxI || opcode == Op_MinI, "Unexpected opcode");
1136   const TypeInt* tx = phase->type(x)->isa_int();
1137   jint x_off = x_operands.second;
1138   jint y_off = y_operands.second;
1139   if (x == y && tx != nullptr &&
1140       !can_overflow(tx, x_off) &&
1141       !can_overflow(tx, y_off)) {
1142     jint c = opcode == Op_MinI ? MIN2(x_off, y_off) : MAX2(x_off, y_off);
1143     return new AddINode(x, phase->intcon(c));
1144   }
1145   return nullptr;
1146 }
1147 
1148 // Try to cast n as an integer addition with a constant. Return:
1149 //   <x, C>,       if n == add(x, C), where 'C' is a non-TOP constant;
1150 //   <nullptr, 0>, if n == add(x, C), where 'C' is a TOP constant; or
1151 //   <n, 0>,       otherwise.
1152 static ConstAddOperands as_add_with_constant(Node* n) {
1153   if (n->Opcode() != Op_AddI) {
1154     return ConstAddOperands(n, 0);
1155   }
1156   Node* x = n->in(1);
1157   Node* c = n->in(2);
1158   if (!c->is_Con()) {
1159     return ConstAddOperands(n, 0);
1160   }
1161   const Type* c_type = c->bottom_type();
1162   if (c_type == Type::TOP) {
1163     return ConstAddOperands(nullptr, 0);
1164   }
1165   return ConstAddOperands(x, c_type->is_int()->get_con());
1166 }
1167 
1168 Node* MaxNode::IdealI(PhaseGVN* phase, bool can_reshape) {
1169   int opcode = Opcode();
1170   assert(opcode == Op_MinI || opcode == Op_MaxI, "Unexpected opcode");
1171   // Try to transform the following pattern, in any of its four possible
1172   // permutations induced by op's commutativity:
1173   //     op(op(add(inner, inner_off), inner_other), add(outer, outer_off))
1174   // into
1175   //     op(add(inner, op(inner_off, outer_off)), inner_other),
1176   // where:
1177   //     op is either MinI or MaxI, and
1178   //     inner == outer, and
1179   //     the additions cannot overflow.
1180   for (uint inner_op_index = 1; inner_op_index <= 2; inner_op_index++) {
1181     if (in(inner_op_index)->Opcode() != opcode) {
1182       continue;
1183     }
1184     Node* outer_add = in(inner_op_index == 1 ? 2 : 1);
1185     ConstAddOperands outer_add_operands = as_add_with_constant(outer_add);
1186     if (outer_add_operands.first == nullptr) {
1187       return nullptr; // outer_add has a TOP input, no need to continue.
1188     }
1189     // One operand is a MinI/MaxI and the other is an integer addition with
1190     // constant. Test the operands of the inner MinI/MaxI.
1191     for (uint inner_add_index = 1; inner_add_index <= 2; inner_add_index++) {
1192       Node* inner_op = in(inner_op_index);
1193       Node* inner_add = inner_op->in(inner_add_index);
1194       ConstAddOperands inner_add_operands = as_add_with_constant(inner_add);
1195       if (inner_add_operands.first == nullptr) {
1196         return nullptr; // inner_add has a TOP input, no need to continue.
1197       }
1198       // Try to extract the inner add.
1199       Node* add_extracted = extract_add(phase, inner_add_operands, outer_add_operands);
1200       if (add_extracted == nullptr) {
1201         continue;
1202       }
1203       Node* add_transformed = phase->transform(add_extracted);
1204       Node* inner_other = inner_op->in(inner_add_index == 1 ? 2 : 1);
1205       return build_min_max_int(add_transformed, inner_other, opcode == Op_MaxI);
1206     }
1207   }
1208   // Try to transform
1209   //     op(add(x, x_off), add(y, y_off))
1210   // into
1211   //     add(x, op(x_off, y_off)),
1212   // where:
1213   //     op is either MinI or MaxI, and
1214   //     inner == outer, and
1215   //     the additions cannot overflow.
1216   ConstAddOperands xC = as_add_with_constant(in(1));
1217   ConstAddOperands yC = as_add_with_constant(in(2));
1218   if (xC.first == nullptr || yC.first == nullptr) return nullptr;
1219   return extract_add(phase, xC, yC);
1220 }
1221 
1222 // Ideal transformations for MaxINode
1223 Node* MaxINode::Ideal(PhaseGVN* phase, bool can_reshape) {
1224   return IdealI(phase, can_reshape);
1225 }
1226 
1227 //=============================================================================
1228 //------------------------------add_ring---------------------------------------
1229 // Supplied function returns the sum of the inputs.
1230 const Type *MaxINode::add_ring( const Type *t0, const Type *t1 ) const {
1231   const TypeInt *r0 = t0->is_int(); // Handy access
1232   const TypeInt *r1 = t1->is_int();
1233 
1234   // Otherwise just MAX them bits.
1235   return TypeInt::make( MAX2(r0->_lo,r1->_lo), MAX2(r0->_hi,r1->_hi), MAX2(r0->_widen,r1->_widen) );
1236 }
1237 
1238 //=============================================================================
1239 //------------------------------Idealize---------------------------------------
1240 // MINs show up in range-check loop limit calculations.  Look for
1241 // "MIN2(x+c0,MIN2(y,x+c1))".  Pick the smaller constant: "MIN2(x+c0,y)"
1242 Node* MinINode::Ideal(PhaseGVN* phase, bool can_reshape) {
1243   return IdealI(phase, can_reshape);
1244 }
1245 
1246 //------------------------------add_ring---------------------------------------
1247 // Supplied function returns the sum of the inputs.
1248 const Type *MinINode::add_ring( const Type *t0, const Type *t1 ) const {
1249   const TypeInt *r0 = t0->is_int(); // Handy access
1250   const TypeInt *r1 = t1->is_int();
1251 
1252   // Otherwise just MIN them bits.
1253   return TypeInt::make( MIN2(r0->_lo,r1->_lo), MIN2(r0->_hi,r1->_hi), MAX2(r0->_widen,r1->_widen) );
1254 }
1255 
1256 // Collapse the "addition with overflow-protection" pattern, and the symmetrical
1257 // "subtraction with underflow-protection" pattern. These are created during the
1258 // unrolling, when we have to adjust the limit by subtracting the stride, but want
1259 // to protect against underflow: MaxL(SubL(limit, stride), min_jint).
1260 // If we have more than one of those in a sequence:
1261 //
1262 //   x  con2
1263 //   |  |
1264 //   AddL  clamp2
1265 //     |    |
1266 //    Max/MinL con1
1267 //          |  |
1268 //          AddL  clamp1
1269 //            |    |
1270 //           Max/MinL (n)
1271 //
1272 // We want to collapse it to:
1273 //
1274 //   x  con1  con2
1275 //   |    |    |
1276 //   |   AddLNode (new_con)
1277 //   |    |
1278 //  AddLNode  clamp1
1279 //        |    |
1280 //       Max/MinL (n)
1281 //
1282 // Note: we assume that SubL was already replaced by an AddL, and that the stride
1283 // has its sign flipped: SubL(limit, stride) -> AddL(limit, -stride).
1284 Node* fold_subI_no_underflow_pattern(Node* n, PhaseGVN* phase) {
1285   assert(n->Opcode() == Op_MaxL || n->Opcode() == Op_MinL, "sanity");
1286   // Check that the two clamps have the correct values.
1287   jlong clamp = (n->Opcode() == Op_MaxL) ? min_jint : max_jint;
1288   auto is_clamp = [&](Node* c) {
1289     const TypeLong* t = phase->type(c)->isa_long();
1290     return t != nullptr && t->is_con() &&
1291            t->get_con() == clamp;
1292   };
1293   // Check that the constants are negative if MaxL, and positive if MinL.
1294   auto is_sub_con = [&](Node* c) {
1295     const TypeLong* t = phase->type(c)->isa_long();
1296     return t != nullptr && t->is_con() &&
1297            t->get_con() < max_jint && t->get_con() > min_jint &&
1298            (t->get_con() < 0) == (n->Opcode() == Op_MaxL);
1299   };
1300   // Verify the graph level by level:
1301   Node* add1   = n->in(1);
1302   Node* clamp1 = n->in(2);
1303   if (add1->Opcode() == Op_AddL && is_clamp(clamp1)) {
1304     Node* max2 = add1->in(1);
1305     Node* con1 = add1->in(2);
1306     if (max2->Opcode() == n->Opcode() && is_sub_con(con1)) {
1307       Node* add2   = max2->in(1);
1308       Node* clamp2 = max2->in(2);
1309       if (add2->Opcode() == Op_AddL && is_clamp(clamp2)) {
1310         Node* x    = add2->in(1);
1311         Node* con2 = add2->in(2);
1312         if (is_sub_con(con2)) {
1313           Node* new_con = phase->transform(new AddLNode(con1, con2));
1314           Node* new_sub = phase->transform(new AddLNode(x, new_con));
1315           n->set_req_X(1, new_sub, phase);
1316           return n;
1317         }
1318       }
1319     }
1320   }
1321   return nullptr;
1322 }
1323 
1324 const Type* MaxLNode::add_ring(const Type* t0, const Type* t1) const {
1325   const TypeLong* r0 = t0->is_long();
1326   const TypeLong* r1 = t1->is_long();
1327 
1328   return TypeLong::make(MAX2(r0->_lo, r1->_lo), MAX2(r0->_hi, r1->_hi), MAX2(r0->_widen, r1->_widen));
1329 }
1330 
1331 Node* MaxLNode::Identity(PhaseGVN* phase) {
1332   const TypeLong* t1 = phase->type(in(1))->is_long();
1333   const TypeLong* t2 = phase->type(in(2))->is_long();
1334 
1335   // Can we determine maximum statically?
1336   if (t1->_lo >= t2->_hi) {
1337     return in(1);
1338   } else if (t2->_lo >= t1->_hi) {
1339     return in(2);
1340   }
1341 
1342   return MaxNode::Identity(phase);
1343 }
1344 
1345 Node* MaxLNode::Ideal(PhaseGVN* phase, bool can_reshape) {
1346   Node* n = AddNode::Ideal(phase, can_reshape);
1347   if (n != nullptr) {
1348     return n;
1349   }
1350   if (can_reshape) {
1351     return fold_subI_no_underflow_pattern(this, phase);
1352   }
1353   return nullptr;
1354 }
1355 
1356 const Type* MinLNode::add_ring(const Type* t0, const Type* t1) const {
1357   const TypeLong* r0 = t0->is_long();
1358   const TypeLong* r1 = t1->is_long();
1359 
1360   return TypeLong::make(MIN2(r0->_lo, r1->_lo), MIN2(r0->_hi, r1->_hi), MIN2(r0->_widen, r1->_widen));
1361 }
1362 
1363 Node* MinLNode::Identity(PhaseGVN* phase) {
1364   const TypeLong* t1 = phase->type(in(1))->is_long();
1365   const TypeLong* t2 = phase->type(in(2))->is_long();
1366 
1367   // Can we determine minimum statically?
1368   if (t1->_lo >= t2->_hi) {
1369     return in(2);
1370   } else if (t2->_lo >= t1->_hi) {
1371     return in(1);
1372   }
1373 
1374   return MaxNode::Identity(phase);
1375 }
1376 
1377 Node* MinLNode::Ideal(PhaseGVN* phase, bool can_reshape) {
1378   Node* n = AddNode::Ideal(phase, can_reshape);
1379   if (n != nullptr) {
1380     return n;
1381   }
1382   if (can_reshape) {
1383     return fold_subI_no_underflow_pattern(this, phase);
1384   }
1385   return nullptr;
1386 }
1387 
1388 //------------------------------add_ring---------------------------------------
1389 const Type* MinFNode::add_ring(const Type* t0, const Type* t1 ) const {
1390   const TypeF* r0 = t0->isa_float_constant();
1391   const TypeF* r1 = t1->isa_float_constant();
1392   if (r0 == nullptr || r1 == nullptr) {
1393     return bottom_type();
1394   }
1395 
1396   if (r0->is_nan()) {
1397     return r0;
1398   }
1399   if (r1->is_nan()) {
1400     return r1;
1401   }
1402 
1403   float f0 = r0->getf();
1404   float f1 = r1->getf();
1405   if (f0 != 0.0f || f1 != 0.0f) {
1406     return f0 < f1 ? r0 : r1;
1407   }
1408 
1409   // handle min of 0.0, -0.0 case.
1410   return (jint_cast(f0) < jint_cast(f1)) ? r0 : r1;
1411 }
1412 
1413 //------------------------------add_ring---------------------------------------
1414 const Type* MinDNode::add_ring(const Type* t0, const Type* t1) const {
1415   const TypeD* r0 = t0->isa_double_constant();
1416   const TypeD* r1 = t1->isa_double_constant();
1417   if (r0 == nullptr || r1 == nullptr) {
1418     return bottom_type();
1419   }
1420 
1421   if (r0->is_nan()) {
1422     return r0;
1423   }
1424   if (r1->is_nan()) {
1425     return r1;
1426   }
1427 
1428   double d0 = r0->getd();
1429   double d1 = r1->getd();
1430   if (d0 != 0.0 || d1 != 0.0) {
1431     return d0 < d1 ? r0 : r1;
1432   }
1433 
1434   // handle min of 0.0, -0.0 case.
1435   return (jlong_cast(d0) < jlong_cast(d1)) ? r0 : r1;
1436 }
1437 
1438 //------------------------------add_ring---------------------------------------
1439 const Type* MaxFNode::add_ring(const Type* t0, const Type* t1) const {
1440   const TypeF* r0 = t0->isa_float_constant();
1441   const TypeF* r1 = t1->isa_float_constant();
1442   if (r0 == nullptr || r1 == nullptr) {
1443     return bottom_type();
1444   }
1445 
1446   if (r0->is_nan()) {
1447     return r0;
1448   }
1449   if (r1->is_nan()) {
1450     return r1;
1451   }
1452 
1453   float f0 = r0->getf();
1454   float f1 = r1->getf();
1455   if (f0 != 0.0f || f1 != 0.0f) {
1456     return f0 > f1 ? r0 : r1;
1457   }
1458 
1459   // handle max of 0.0,-0.0 case.
1460   return (jint_cast(f0) > jint_cast(f1)) ? r0 : r1;
1461 }
1462 
1463 //------------------------------add_ring---------------------------------------
1464 const Type* MaxDNode::add_ring(const Type* t0, const Type* t1) const {
1465   const TypeD* r0 = t0->isa_double_constant();
1466   const TypeD* r1 = t1->isa_double_constant();
1467   if (r0 == nullptr || r1 == nullptr) {
1468     return bottom_type();
1469   }
1470 
1471   if (r0->is_nan()) {
1472     return r0;
1473   }
1474   if (r1->is_nan()) {
1475     return r1;
1476   }
1477 
1478   double d0 = r0->getd();
1479   double d1 = r1->getd();
1480   if (d0 != 0.0 || d1 != 0.0) {
1481     return d0 > d1 ? r0 : r1;
1482   }
1483 
1484   // handle max of 0.0, -0.0 case.
1485   return (jlong_cast(d0) > jlong_cast(d1)) ? r0 : r1;
1486 }