Wed, 28 Aug 2013 11:22:43 +0200
8023597: Optimize G1 barriers code for unsafe load_store
Summary: Avoid loading old values in G1 pre-barriers for inlined unsafe load_store nodes.
Reviewed-by: kvn, tonyp
Contributed-by: Martin Doerr <martin.doerr@sap.com>
duke@435 | 1 | /* |
drchase@4944 | 2 | * Copyright (c) 1997, 2013, Oracle and/or its affiliates. All rights reserved. |
duke@435 | 3 | * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
duke@435 | 4 | * |
duke@435 | 5 | * This code is free software; you can redistribute it and/or modify it |
duke@435 | 6 | * under the terms of the GNU General Public License version 2 only, as |
duke@435 | 7 | * published by the Free Software Foundation. |
duke@435 | 8 | * |
duke@435 | 9 | * This code is distributed in the hope that it will be useful, but WITHOUT |
duke@435 | 10 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
duke@435 | 11 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
duke@435 | 12 | * version 2 for more details (a copy is included in the LICENSE file that |
duke@435 | 13 | * accompanied this code). |
duke@435 | 14 | * |
duke@435 | 15 | * You should have received a copy of the GNU General Public License version |
duke@435 | 16 | * 2 along with this work; if not, write to the Free Software Foundation, |
duke@435 | 17 | * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
duke@435 | 18 | * |
trims@1907 | 19 | * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
trims@1907 | 20 | * or visit www.oracle.com if you need additional information or have any |
trims@1907 | 21 | * questions. |
duke@435 | 22 | * |
duke@435 | 23 | */ |
duke@435 | 24 | |
stefank@2314 | 25 | #include "precompiled.hpp" |
stefank@2314 | 26 | #include "classfile/systemDictionary.hpp" |
stefank@2314 | 27 | #include "memory/allocation.inline.hpp" |
stefank@2314 | 28 | #include "oops/objArrayKlass.hpp" |
stefank@2314 | 29 | #include "opto/addnode.hpp" |
stefank@2314 | 30 | #include "opto/cfgnode.hpp" |
stefank@2314 | 31 | #include "opto/connode.hpp" |
stefank@2314 | 32 | #include "opto/loopnode.hpp" |
stefank@2314 | 33 | #include "opto/machnode.hpp" |
stefank@2314 | 34 | #include "opto/mulnode.hpp" |
stefank@2314 | 35 | #include "opto/phaseX.hpp" |
stefank@2314 | 36 | #include "opto/regmask.hpp" |
stefank@2314 | 37 | #include "opto/runtime.hpp" |
stefank@2314 | 38 | #include "opto/subnode.hpp" |
stefank@2314 | 39 | |
duke@435 | 40 | // Portions of code courtesy of Clifford Click |
duke@435 | 41 | |
duke@435 | 42 | // Optimization - Graph Style |
duke@435 | 43 | |
duke@435 | 44 | //============================================================================= |
duke@435 | 45 | //------------------------------Value------------------------------------------ |
duke@435 | 46 | // Compute the type of the RegionNode. |
duke@435 | 47 | const Type *RegionNode::Value( PhaseTransform *phase ) const { |
duke@435 | 48 | for( uint i=1; i<req(); ++i ) { // For all paths in |
duke@435 | 49 | Node *n = in(i); // Get Control source |
duke@435 | 50 | if( !n ) continue; // Missing inputs are TOP |
duke@435 | 51 | if( phase->type(n) == Type::CONTROL ) |
duke@435 | 52 | return Type::CONTROL; |
duke@435 | 53 | } |
duke@435 | 54 | return Type::TOP; // All paths dead? Then so are we |
duke@435 | 55 | } |
duke@435 | 56 | |
duke@435 | 57 | //------------------------------Identity--------------------------------------- |
duke@435 | 58 | // Check for Region being Identity. |
duke@435 | 59 | Node *RegionNode::Identity( PhaseTransform *phase ) { |
duke@435 | 60 | // Cannot have Region be an identity, even if it has only 1 input. |
duke@435 | 61 | // Phi users cannot have their Region input folded away for them, |
duke@435 | 62 | // since they need to select the proper data input |
duke@435 | 63 | return this; |
duke@435 | 64 | } |
duke@435 | 65 | |
duke@435 | 66 | //------------------------------merge_region----------------------------------- |
duke@435 | 67 | // If a Region flows into a Region, merge into one big happy merge. This is |
duke@435 | 68 | // hard to do if there is stuff that has to happen |
duke@435 | 69 | static Node *merge_region(RegionNode *region, PhaseGVN *phase) { |
duke@435 | 70 | if( region->Opcode() != Op_Region ) // Do not do to LoopNodes |
duke@435 | 71 | return NULL; |
duke@435 | 72 | Node *progress = NULL; // Progress flag |
duke@435 | 73 | PhaseIterGVN *igvn = phase->is_IterGVN(); |
duke@435 | 74 | |
duke@435 | 75 | uint rreq = region->req(); |
duke@435 | 76 | for( uint i = 1; i < rreq; i++ ) { |
duke@435 | 77 | Node *r = region->in(i); |
duke@435 | 78 | if( r && r->Opcode() == Op_Region && // Found a region? |
duke@435 | 79 | r->in(0) == r && // Not already collapsed? |
duke@435 | 80 | r != region && // Avoid stupid situations |
duke@435 | 81 | r->outcnt() == 2 ) { // Self user and 'region' user only? |
duke@435 | 82 | assert(!r->as_Region()->has_phi(), "no phi users"); |
duke@435 | 83 | if( !progress ) { // No progress |
duke@435 | 84 | if (region->has_phi()) { |
duke@435 | 85 | return NULL; // Only flatten if no Phi users |
duke@435 | 86 | // igvn->hash_delete( phi ); |
duke@435 | 87 | } |
duke@435 | 88 | igvn->hash_delete( region ); |
duke@435 | 89 | progress = region; // Making progress |
duke@435 | 90 | } |
duke@435 | 91 | igvn->hash_delete( r ); |
duke@435 | 92 | |
duke@435 | 93 | // Append inputs to 'r' onto 'region' |
duke@435 | 94 | for( uint j = 1; j < r->req(); j++ ) { |
duke@435 | 95 | // Move an input from 'r' to 'region' |
duke@435 | 96 | region->add_req(r->in(j)); |
duke@435 | 97 | r->set_req(j, phase->C->top()); |
duke@435 | 98 | // Update phis of 'region' |
duke@435 | 99 | //for( uint k = 0; k < max; k++ ) { |
duke@435 | 100 | // Node *phi = region->out(k); |
duke@435 | 101 | // if( phi->is_Phi() ) { |
duke@435 | 102 | // phi->add_req(phi->in(i)); |
duke@435 | 103 | // } |
duke@435 | 104 | //} |
duke@435 | 105 | |
duke@435 | 106 | rreq++; // One more input to Region |
duke@435 | 107 | } // Found a region to merge into Region |
duke@435 | 108 | // Clobber pointer to the now dead 'r' |
duke@435 | 109 | region->set_req(i, phase->C->top()); |
duke@435 | 110 | } |
duke@435 | 111 | } |
duke@435 | 112 | |
duke@435 | 113 | return progress; |
duke@435 | 114 | } |
duke@435 | 115 | |
duke@435 | 116 | |
duke@435 | 117 | |
duke@435 | 118 | //--------------------------------has_phi-------------------------------------- |
duke@435 | 119 | // Helper function: Return any PhiNode that uses this region or NULL |
duke@435 | 120 | PhiNode* RegionNode::has_phi() const { |
duke@435 | 121 | for (DUIterator_Fast imax, i = fast_outs(imax); i < imax; i++) { |
duke@435 | 122 | Node* phi = fast_out(i); |
duke@435 | 123 | if (phi->is_Phi()) { // Check for Phi users |
duke@435 | 124 | assert(phi->in(0) == (Node*)this, "phi uses region only via in(0)"); |
duke@435 | 125 | return phi->as_Phi(); // this one is good enough |
duke@435 | 126 | } |
duke@435 | 127 | } |
duke@435 | 128 | |
duke@435 | 129 | return NULL; |
duke@435 | 130 | } |
duke@435 | 131 | |
duke@435 | 132 | |
duke@435 | 133 | //-----------------------------has_unique_phi---------------------------------- |
duke@435 | 134 | // Helper function: Return the only PhiNode that uses this region or NULL |
duke@435 | 135 | PhiNode* RegionNode::has_unique_phi() const { |
duke@435 | 136 | // Check that only one use is a Phi |
duke@435 | 137 | PhiNode* only_phi = NULL; |
duke@435 | 138 | for (DUIterator_Fast imax, i = fast_outs(imax); i < imax; i++) { |
duke@435 | 139 | Node* phi = fast_out(i); |
duke@435 | 140 | if (phi->is_Phi()) { // Check for Phi users |
duke@435 | 141 | assert(phi->in(0) == (Node*)this, "phi uses region only via in(0)"); |
duke@435 | 142 | if (only_phi == NULL) { |
duke@435 | 143 | only_phi = phi->as_Phi(); |
duke@435 | 144 | } else { |
duke@435 | 145 | return NULL; // multiple phis |
duke@435 | 146 | } |
duke@435 | 147 | } |
duke@435 | 148 | } |
duke@435 | 149 | |
duke@435 | 150 | return only_phi; |
duke@435 | 151 | } |
duke@435 | 152 | |
duke@435 | 153 | |
duke@435 | 154 | //------------------------------check_phi_clipping----------------------------- |
duke@435 | 155 | // Helper function for RegionNode's identification of FP clipping |
duke@435 | 156 | // Check inputs to the Phi |
duke@435 | 157 | static bool check_phi_clipping( PhiNode *phi, ConNode * &min, uint &min_idx, ConNode * &max, uint &max_idx, Node * &val, uint &val_idx ) { |
duke@435 | 158 | min = NULL; |
duke@435 | 159 | max = NULL; |
duke@435 | 160 | val = NULL; |
duke@435 | 161 | min_idx = 0; |
duke@435 | 162 | max_idx = 0; |
duke@435 | 163 | val_idx = 0; |
duke@435 | 164 | uint phi_max = phi->req(); |
duke@435 | 165 | if( phi_max == 4 ) { |
duke@435 | 166 | for( uint j = 1; j < phi_max; ++j ) { |
duke@435 | 167 | Node *n = phi->in(j); |
duke@435 | 168 | int opcode = n->Opcode(); |
duke@435 | 169 | switch( opcode ) { |
duke@435 | 170 | case Op_ConI: |
duke@435 | 171 | { |
duke@435 | 172 | if( min == NULL ) { |
duke@435 | 173 | min = n->Opcode() == Op_ConI ? (ConNode*)n : NULL; |
duke@435 | 174 | min_idx = j; |
duke@435 | 175 | } else { |
duke@435 | 176 | max = n->Opcode() == Op_ConI ? (ConNode*)n : NULL; |
duke@435 | 177 | max_idx = j; |
duke@435 | 178 | if( min->get_int() > max->get_int() ) { |
duke@435 | 179 | // Swap min and max |
duke@435 | 180 | ConNode *temp; |
duke@435 | 181 | uint temp_idx; |
duke@435 | 182 | temp = min; min = max; max = temp; |
duke@435 | 183 | temp_idx = min_idx; min_idx = max_idx; max_idx = temp_idx; |
duke@435 | 184 | } |
duke@435 | 185 | } |
duke@435 | 186 | } |
duke@435 | 187 | break; |
duke@435 | 188 | default: |
duke@435 | 189 | { |
duke@435 | 190 | val = n; |
duke@435 | 191 | val_idx = j; |
duke@435 | 192 | } |
duke@435 | 193 | break; |
duke@435 | 194 | } |
duke@435 | 195 | } |
duke@435 | 196 | } |
duke@435 | 197 | return ( min && max && val && (min->get_int() <= 0) && (max->get_int() >=0) ); |
duke@435 | 198 | } |
duke@435 | 199 | |
duke@435 | 200 | |
duke@435 | 201 | //------------------------------check_if_clipping------------------------------ |
duke@435 | 202 | // Helper function for RegionNode's identification of FP clipping |
duke@435 | 203 | // Check that inputs to Region come from two IfNodes, |
duke@435 | 204 | // |
duke@435 | 205 | // If |
duke@435 | 206 | // False True |
duke@435 | 207 | // If | |
duke@435 | 208 | // False True | |
duke@435 | 209 | // | | | |
duke@435 | 210 | // RegionNode_inputs |
duke@435 | 211 | // |
duke@435 | 212 | static bool check_if_clipping( const RegionNode *region, IfNode * &bot_if, IfNode * &top_if ) { |
duke@435 | 213 | top_if = NULL; |
duke@435 | 214 | bot_if = NULL; |
duke@435 | 215 | |
duke@435 | 216 | // Check control structure above RegionNode for (if ( if ) ) |
duke@435 | 217 | Node *in1 = region->in(1); |
duke@435 | 218 | Node *in2 = region->in(2); |
duke@435 | 219 | Node *in3 = region->in(3); |
duke@435 | 220 | // Check that all inputs are projections |
duke@435 | 221 | if( in1->is_Proj() && in2->is_Proj() && in3->is_Proj() ) { |
duke@435 | 222 | Node *in10 = in1->in(0); |
duke@435 | 223 | Node *in20 = in2->in(0); |
duke@435 | 224 | Node *in30 = in3->in(0); |
duke@435 | 225 | // Check that #1 and #2 are ifTrue and ifFalse from same If |
duke@435 | 226 | if( in10 != NULL && in10->is_If() && |
duke@435 | 227 | in20 != NULL && in20->is_If() && |
duke@435 | 228 | in30 != NULL && in30->is_If() && in10 == in20 && |
duke@435 | 229 | (in1->Opcode() != in2->Opcode()) ) { |
duke@435 | 230 | Node *in100 = in10->in(0); |
duke@435 | 231 | Node *in1000 = (in100 != NULL && in100->is_Proj()) ? in100->in(0) : NULL; |
duke@435 | 232 | // Check that control for in10 comes from other branch of IF from in3 |
duke@435 | 233 | if( in1000 != NULL && in1000->is_If() && |
duke@435 | 234 | in30 == in1000 && (in3->Opcode() != in100->Opcode()) ) { |
duke@435 | 235 | // Control pattern checks |
duke@435 | 236 | top_if = (IfNode*)in1000; |
duke@435 | 237 | bot_if = (IfNode*)in10; |
duke@435 | 238 | } |
duke@435 | 239 | } |
duke@435 | 240 | } |
duke@435 | 241 | |
duke@435 | 242 | return (top_if != NULL); |
duke@435 | 243 | } |
duke@435 | 244 | |
duke@435 | 245 | |
duke@435 | 246 | //------------------------------check_convf2i_clipping------------------------- |
duke@435 | 247 | // Helper function for RegionNode's identification of FP clipping |
duke@435 | 248 | // Verify that the value input to the phi comes from "ConvF2I; LShift; RShift" |
duke@435 | 249 | static bool check_convf2i_clipping( PhiNode *phi, uint idx, ConvF2INode * &convf2i, Node *min, Node *max) { |
duke@435 | 250 | convf2i = NULL; |
duke@435 | 251 | |
duke@435 | 252 | // Check for the RShiftNode |
duke@435 | 253 | Node *rshift = phi->in(idx); |
duke@435 | 254 | assert( rshift, "Previous checks ensure phi input is present"); |
duke@435 | 255 | if( rshift->Opcode() != Op_RShiftI ) { return false; } |
duke@435 | 256 | |
duke@435 | 257 | // Check for the LShiftNode |
duke@435 | 258 | Node *lshift = rshift->in(1); |
duke@435 | 259 | assert( lshift, "Previous checks ensure phi input is present"); |
duke@435 | 260 | if( lshift->Opcode() != Op_LShiftI ) { return false; } |
duke@435 | 261 | |
duke@435 | 262 | // Check for the ConvF2INode |
duke@435 | 263 | Node *conv = lshift->in(1); |
duke@435 | 264 | if( conv->Opcode() != Op_ConvF2I ) { return false; } |
duke@435 | 265 | |
duke@435 | 266 | // Check that shift amounts are only to get sign bits set after F2I |
duke@435 | 267 | jint max_cutoff = max->get_int(); |
duke@435 | 268 | jint min_cutoff = min->get_int(); |
duke@435 | 269 | jint left_shift = lshift->in(2)->get_int(); |
duke@435 | 270 | jint right_shift = rshift->in(2)->get_int(); |
duke@435 | 271 | jint max_post_shift = nth_bit(BitsPerJavaInteger - left_shift - 1); |
duke@435 | 272 | if( left_shift != right_shift || |
duke@435 | 273 | 0 > left_shift || left_shift >= BitsPerJavaInteger || |
duke@435 | 274 | max_post_shift < max_cutoff || |
duke@435 | 275 | max_post_shift < -min_cutoff ) { |
duke@435 | 276 | // Shifts are necessary but current transformation eliminates them |
duke@435 | 277 | return false; |
duke@435 | 278 | } |
duke@435 | 279 | |
duke@435 | 280 | // OK to return the result of ConvF2I without shifting |
duke@435 | 281 | convf2i = (ConvF2INode*)conv; |
duke@435 | 282 | return true; |
duke@435 | 283 | } |
duke@435 | 284 | |
duke@435 | 285 | |
duke@435 | 286 | //------------------------------check_compare_clipping------------------------- |
duke@435 | 287 | // Helper function for RegionNode's identification of FP clipping |
duke@435 | 288 | static bool check_compare_clipping( bool less_than, IfNode *iff, ConNode *limit, Node * & input ) { |
duke@435 | 289 | Node *i1 = iff->in(1); |
duke@435 | 290 | if ( !i1->is_Bool() ) { return false; } |
duke@435 | 291 | BoolNode *bool1 = i1->as_Bool(); |
duke@435 | 292 | if( less_than && bool1->_test._test != BoolTest::le ) { return false; } |
duke@435 | 293 | else if( !less_than && bool1->_test._test != BoolTest::lt ) { return false; } |
duke@435 | 294 | const Node *cmpF = bool1->in(1); |
duke@435 | 295 | if( cmpF->Opcode() != Op_CmpF ) { return false; } |
duke@435 | 296 | // Test that the float value being compared against |
duke@435 | 297 | // is equivalent to the int value used as a limit |
duke@435 | 298 | Node *nodef = cmpF->in(2); |
duke@435 | 299 | if( nodef->Opcode() != Op_ConF ) { return false; } |
duke@435 | 300 | jfloat conf = nodef->getf(); |
duke@435 | 301 | jint coni = limit->get_int(); |
duke@435 | 302 | if( ((int)conf) != coni ) { return false; } |
duke@435 | 303 | input = cmpF->in(1); |
duke@435 | 304 | return true; |
duke@435 | 305 | } |
duke@435 | 306 | |
duke@435 | 307 | //------------------------------is_unreachable_region-------------------------- |
duke@435 | 308 | // Find if the Region node is reachable from the root. |
duke@435 | 309 | bool RegionNode::is_unreachable_region(PhaseGVN *phase) const { |
duke@435 | 310 | assert(req() == 2, ""); |
duke@435 | 311 | |
duke@435 | 312 | // First, cut the simple case of fallthrough region when NONE of |
duke@435 | 313 | // region's phis references itself directly or through a data node. |
duke@435 | 314 | uint max = outcnt(); |
duke@435 | 315 | uint i; |
duke@435 | 316 | for (i = 0; i < max; i++) { |
duke@435 | 317 | Node* phi = raw_out(i); |
duke@435 | 318 | if (phi != NULL && phi->is_Phi()) { |
duke@435 | 319 | assert(phase->eqv(phi->in(0), this) && phi->req() == 2, ""); |
duke@435 | 320 | if (phi->outcnt() == 0) |
duke@435 | 321 | continue; // Safe case - no loops |
duke@435 | 322 | if (phi->outcnt() == 1) { |
duke@435 | 323 | Node* u = phi->raw_out(0); |
duke@435 | 324 | // Skip if only one use is an other Phi or Call or Uncommon trap. |
duke@435 | 325 | // It is safe to consider this case as fallthrough. |
duke@435 | 326 | if (u != NULL && (u->is_Phi() || u->is_CFG())) |
duke@435 | 327 | continue; |
duke@435 | 328 | } |
duke@435 | 329 | // Check when phi references itself directly or through an other node. |
duke@435 | 330 | if (phi->as_Phi()->simple_data_loop_check(phi->in(1)) >= PhiNode::Unsafe) |
duke@435 | 331 | break; // Found possible unsafe data loop. |
duke@435 | 332 | } |
duke@435 | 333 | } |
duke@435 | 334 | if (i >= max) |
duke@435 | 335 | return false; // An unsafe case was NOT found - don't need graph walk. |
duke@435 | 336 | |
duke@435 | 337 | // Unsafe case - check if the Region node is reachable from root. |
duke@435 | 338 | ResourceMark rm; |
duke@435 | 339 | |
duke@435 | 340 | Arena *a = Thread::current()->resource_area(); |
duke@435 | 341 | Node_List nstack(a); |
duke@435 | 342 | VectorSet visited(a); |
duke@435 | 343 | |
duke@435 | 344 | // Mark all control nodes reachable from root outputs |
duke@435 | 345 | Node *n = (Node*)phase->C->root(); |
duke@435 | 346 | nstack.push(n); |
duke@435 | 347 | visited.set(n->_idx); |
duke@435 | 348 | while (nstack.size() != 0) { |
duke@435 | 349 | n = nstack.pop(); |
duke@435 | 350 | uint max = n->outcnt(); |
duke@435 | 351 | for (uint i = 0; i < max; i++) { |
duke@435 | 352 | Node* m = n->raw_out(i); |
duke@435 | 353 | if (m != NULL && m->is_CFG()) { |
duke@435 | 354 | if (phase->eqv(m, this)) { |
duke@435 | 355 | return false; // We reached the Region node - it is not dead. |
duke@435 | 356 | } |
duke@435 | 357 | if (!visited.test_set(m->_idx)) |
duke@435 | 358 | nstack.push(m); |
duke@435 | 359 | } |
duke@435 | 360 | } |
duke@435 | 361 | } |
duke@435 | 362 | |
duke@435 | 363 | return true; // The Region node is unreachable - it is dead. |
duke@435 | 364 | } |
duke@435 | 365 | |
roland@4409 | 366 | bool RegionNode::try_clean_mem_phi(PhaseGVN *phase) { |
roland@4409 | 367 | // Incremental inlining + PhaseStringOpts sometimes produce: |
roland@4409 | 368 | // |
roland@4409 | 369 | // cmpP with 1 top input |
roland@4409 | 370 | // | |
roland@4409 | 371 | // If |
roland@4409 | 372 | // / \ |
roland@4409 | 373 | // IfFalse IfTrue /- Some Node |
roland@4409 | 374 | // \ / / / |
roland@4409 | 375 | // Region / /-MergeMem |
roland@4409 | 376 | // \---Phi |
roland@4409 | 377 | // |
roland@4409 | 378 | // |
roland@4409 | 379 | // It's expected by PhaseStringOpts that the Region goes away and is |
roland@4409 | 380 | // replaced by If's control input but because there's still a Phi, |
roland@4409 | 381 | // the Region stays in the graph. The top input from the cmpP is |
roland@4409 | 382 | // propagated forward and a subgraph that is useful goes away. The |
roland@4409 | 383 | // code below replaces the Phi with the MergeMem so that the Region |
roland@4409 | 384 | // is simplified. |
roland@4409 | 385 | |
roland@4409 | 386 | PhiNode* phi = has_unique_phi(); |
roland@4409 | 387 | if (phi && phi->type() == Type::MEMORY && req() == 3 && phi->is_diamond_phi(true)) { |
roland@4409 | 388 | MergeMemNode* m = NULL; |
roland@4409 | 389 | assert(phi->req() == 3, "same as region"); |
roland@4409 | 390 | for (uint i = 1; i < 3; ++i) { |
roland@4409 | 391 | Node *mem = phi->in(i); |
roland@4409 | 392 | if (mem && mem->is_MergeMem() && in(i)->outcnt() == 1) { |
roland@4409 | 393 | // Nothing is control-dependent on path #i except the region itself. |
roland@4409 | 394 | m = mem->as_MergeMem(); |
roland@4409 | 395 | uint j = 3 - i; |
roland@4409 | 396 | Node* other = phi->in(j); |
roland@4409 | 397 | if (other && other == m->base_memory()) { |
roland@4409 | 398 | // m is a successor memory to other, and is not pinned inside the diamond, so push it out. |
roland@4409 | 399 | // This will allow the diamond to collapse completely. |
roland@4409 | 400 | phase->is_IterGVN()->replace_node(phi, m); |
roland@4409 | 401 | return true; |
roland@4409 | 402 | } |
roland@4409 | 403 | } |
roland@4409 | 404 | } |
roland@4409 | 405 | } |
roland@4409 | 406 | return false; |
roland@4409 | 407 | } |
roland@4409 | 408 | |
duke@435 | 409 | //------------------------------Ideal------------------------------------------ |
duke@435 | 410 | // Return a node which is more "ideal" than the current node. Must preserve |
duke@435 | 411 | // the CFG, but we can still strip out dead paths. |
duke@435 | 412 | Node *RegionNode::Ideal(PhaseGVN *phase, bool can_reshape) { |
duke@435 | 413 | if( !can_reshape && !in(0) ) return NULL; // Already degraded to a Copy |
duke@435 | 414 | assert(!in(0) || !in(0)->is_Root(), "not a specially hidden merge"); |
duke@435 | 415 | |
duke@435 | 416 | // Check for RegionNode with no Phi users and both inputs come from either |
duke@435 | 417 | // arm of the same IF. If found, then the control-flow split is useless. |
duke@435 | 418 | bool has_phis = false; |
duke@435 | 419 | if (can_reshape) { // Need DU info to check for Phi users |
duke@435 | 420 | has_phis = (has_phi() != NULL); // Cache result |
roland@4409 | 421 | if (has_phis && try_clean_mem_phi(phase)) { |
roland@4409 | 422 | has_phis = false; |
roland@4409 | 423 | } |
roland@4409 | 424 | |
duke@435 | 425 | if (!has_phis) { // No Phi users? Nothing merging? |
duke@435 | 426 | for (uint i = 1; i < req()-1; i++) { |
duke@435 | 427 | Node *if1 = in(i); |
duke@435 | 428 | if( !if1 ) continue; |
duke@435 | 429 | Node *iff = if1->in(0); |
duke@435 | 430 | if( !iff || !iff->is_If() ) continue; |
duke@435 | 431 | for( uint j=i+1; j<req(); j++ ) { |
duke@435 | 432 | if( in(j) && in(j)->in(0) == iff && |
duke@435 | 433 | if1->Opcode() != in(j)->Opcode() ) { |
duke@435 | 434 | // Add the IF Projections to the worklist. They (and the IF itself) |
duke@435 | 435 | // will be eliminated if dead. |
duke@435 | 436 | phase->is_IterGVN()->add_users_to_worklist(iff); |
duke@435 | 437 | set_req(i, iff->in(0));// Skip around the useless IF diamond |
duke@435 | 438 | set_req(j, NULL); |
duke@435 | 439 | return this; // Record progress |
duke@435 | 440 | } |
duke@435 | 441 | } |
duke@435 | 442 | } |
duke@435 | 443 | } |
duke@435 | 444 | } |
duke@435 | 445 | |
duke@435 | 446 | // Remove TOP or NULL input paths. If only 1 input path remains, this Region |
duke@435 | 447 | // degrades to a copy. |
duke@435 | 448 | bool add_to_worklist = false; |
duke@435 | 449 | int cnt = 0; // Count of values merging |
duke@435 | 450 | DEBUG_ONLY( int cnt_orig = req(); ) // Save original inputs count |
duke@435 | 451 | int del_it = 0; // The last input path we delete |
duke@435 | 452 | // For all inputs... |
duke@435 | 453 | for( uint i=1; i<req(); ++i ){// For all paths in |
duke@435 | 454 | Node *n = in(i); // Get the input |
duke@435 | 455 | if( n != NULL ) { |
duke@435 | 456 | // Remove useless control copy inputs |
duke@435 | 457 | if( n->is_Region() && n->as_Region()->is_copy() ) { |
duke@435 | 458 | set_req(i, n->nonnull_req()); |
duke@435 | 459 | i--; |
duke@435 | 460 | continue; |
duke@435 | 461 | } |
duke@435 | 462 | if( n->is_Proj() ) { // Remove useless rethrows |
duke@435 | 463 | Node *call = n->in(0); |
duke@435 | 464 | if (call->is_Call() && call->as_Call()->entry_point() == OptoRuntime::rethrow_stub()) { |
duke@435 | 465 | set_req(i, call->in(0)); |
duke@435 | 466 | i--; |
duke@435 | 467 | continue; |
duke@435 | 468 | } |
duke@435 | 469 | } |
duke@435 | 470 | if( phase->type(n) == Type::TOP ) { |
duke@435 | 471 | set_req(i, NULL); // Ignore TOP inputs |
duke@435 | 472 | i--; |
duke@435 | 473 | continue; |
duke@435 | 474 | } |
duke@435 | 475 | cnt++; // One more value merging |
duke@435 | 476 | |
duke@435 | 477 | } else if (can_reshape) { // Else found dead path with DU info |
duke@435 | 478 | PhaseIterGVN *igvn = phase->is_IterGVN(); |
duke@435 | 479 | del_req(i); // Yank path from self |
duke@435 | 480 | del_it = i; |
duke@435 | 481 | uint max = outcnt(); |
duke@435 | 482 | DUIterator j; |
duke@435 | 483 | bool progress = true; |
duke@435 | 484 | while(progress) { // Need to establish property over all users |
duke@435 | 485 | progress = false; |
duke@435 | 486 | for (j = outs(); has_out(j); j++) { |
duke@435 | 487 | Node *n = out(j); |
duke@435 | 488 | if( n->req() != req() && n->is_Phi() ) { |
duke@435 | 489 | assert( n->in(0) == this, "" ); |
duke@435 | 490 | igvn->hash_delete(n); // Yank from hash before hacking edges |
duke@435 | 491 | n->set_req_X(i,NULL,igvn);// Correct DU info |
duke@435 | 492 | n->del_req(i); // Yank path from Phis |
duke@435 | 493 | if( max != outcnt() ) { |
duke@435 | 494 | progress = true; |
duke@435 | 495 | j = refresh_out_pos(j); |
duke@435 | 496 | max = outcnt(); |
duke@435 | 497 | } |
duke@435 | 498 | } |
duke@435 | 499 | } |
duke@435 | 500 | } |
duke@435 | 501 | add_to_worklist = true; |
duke@435 | 502 | i--; |
duke@435 | 503 | } |
duke@435 | 504 | } |
duke@435 | 505 | |
duke@435 | 506 | if (can_reshape && cnt == 1) { |
duke@435 | 507 | // Is it dead loop? |
duke@435 | 508 | // If it is LoopNopde it had 2 (+1 itself) inputs and |
duke@435 | 509 | // one of them was cut. The loop is dead if it was EntryContol. |
kvn@3309 | 510 | // Loop node may have only one input because entry path |
kvn@3309 | 511 | // is removed in PhaseIdealLoop::Dominators(). |
kvn@3309 | 512 | assert(!this->is_Loop() || cnt_orig <= 3, "Loop node should have 3 or less inputs"); |
kvn@3309 | 513 | if (this->is_Loop() && (del_it == LoopNode::EntryControl || |
kvn@3309 | 514 | del_it == 0 && is_unreachable_region(phase)) || |
duke@435 | 515 | !this->is_Loop() && has_phis && is_unreachable_region(phase)) { |
duke@435 | 516 | // Yes, the region will be removed during the next step below. |
duke@435 | 517 | // Cut the backedge input and remove phis since no data paths left. |
duke@435 | 518 | // We don't cut outputs to other nodes here since we need to put them |
duke@435 | 519 | // on the worklist. |
duke@435 | 520 | del_req(1); |
duke@435 | 521 | cnt = 0; |
duke@435 | 522 | assert( req() == 1, "no more inputs expected" ); |
duke@435 | 523 | uint max = outcnt(); |
duke@435 | 524 | bool progress = true; |
duke@435 | 525 | Node *top = phase->C->top(); |
duke@435 | 526 | PhaseIterGVN *igvn = phase->is_IterGVN(); |
duke@435 | 527 | DUIterator j; |
duke@435 | 528 | while(progress) { |
duke@435 | 529 | progress = false; |
duke@435 | 530 | for (j = outs(); has_out(j); j++) { |
duke@435 | 531 | Node *n = out(j); |
duke@435 | 532 | if( n->is_Phi() ) { |
duke@435 | 533 | assert( igvn->eqv(n->in(0), this), "" ); |
duke@435 | 534 | assert( n->req() == 2 && n->in(1) != NULL, "Only one data input expected" ); |
duke@435 | 535 | // Break dead loop data path. |
duke@435 | 536 | // Eagerly replace phis with top to avoid phis copies generation. |
kvn@1976 | 537 | igvn->replace_node(n, top); |
duke@435 | 538 | if( max != outcnt() ) { |
duke@435 | 539 | progress = true; |
duke@435 | 540 | j = refresh_out_pos(j); |
duke@435 | 541 | max = outcnt(); |
duke@435 | 542 | } |
duke@435 | 543 | } |
duke@435 | 544 | } |
duke@435 | 545 | } |
duke@435 | 546 | add_to_worklist = true; |
duke@435 | 547 | } |
duke@435 | 548 | } |
duke@435 | 549 | if (add_to_worklist) { |
duke@435 | 550 | phase->is_IterGVN()->add_users_to_worklist(this); // Revisit collapsed Phis |
duke@435 | 551 | } |
duke@435 | 552 | |
duke@435 | 553 | if( cnt <= 1 ) { // Only 1 path in? |
duke@435 | 554 | set_req(0, NULL); // Null control input for region copy |
duke@435 | 555 | if( cnt == 0 && !can_reshape) { // Parse phase - leave the node as it is. |
duke@435 | 556 | // No inputs or all inputs are NULL. |
duke@435 | 557 | return NULL; |
duke@435 | 558 | } else if (can_reshape) { // Optimization phase - remove the node |
duke@435 | 559 | PhaseIterGVN *igvn = phase->is_IterGVN(); |
duke@435 | 560 | Node *parent_ctrl; |
duke@435 | 561 | if( cnt == 0 ) { |
duke@435 | 562 | assert( req() == 1, "no inputs expected" ); |
duke@435 | 563 | // During IGVN phase such region will be subsumed by TOP node |
duke@435 | 564 | // so region's phis will have TOP as control node. |
duke@435 | 565 | // Kill phis here to avoid it. PhiNode::is_copy() will be always false. |
duke@435 | 566 | // Also set other user's input to top. |
duke@435 | 567 | parent_ctrl = phase->C->top(); |
duke@435 | 568 | } else { |
duke@435 | 569 | // The fallthrough case since we already checked dead loops above. |
duke@435 | 570 | parent_ctrl = in(1); |
duke@435 | 571 | assert(parent_ctrl != NULL, "Region is a copy of some non-null control"); |
duke@435 | 572 | assert(!igvn->eqv(parent_ctrl, this), "Close dead loop"); |
duke@435 | 573 | } |
duke@435 | 574 | if (!add_to_worklist) |
duke@435 | 575 | igvn->add_users_to_worklist(this); // Check for further allowed opts |
duke@435 | 576 | for (DUIterator_Last imin, i = last_outs(imin); i >= imin; --i) { |
duke@435 | 577 | Node* n = last_out(i); |
duke@435 | 578 | igvn->hash_delete(n); // Remove from worklist before modifying edges |
duke@435 | 579 | if( n->is_Phi() ) { // Collapse all Phis |
duke@435 | 580 | // Eagerly replace phis to avoid copies generation. |
kvn@1976 | 581 | Node* in; |
duke@435 | 582 | if( cnt == 0 ) { |
duke@435 | 583 | assert( n->req() == 1, "No data inputs expected" ); |
kvn@1976 | 584 | in = parent_ctrl; // replaced by top |
duke@435 | 585 | } else { |
duke@435 | 586 | assert( n->req() == 2 && n->in(1) != NULL, "Only one data input expected" ); |
kvn@1976 | 587 | in = n->in(1); // replaced by unique input |
kvn@1976 | 588 | if( n->as_Phi()->is_unsafe_data_reference(in) ) |
kvn@1976 | 589 | in = phase->C->top(); // replaced by top |
duke@435 | 590 | } |
kvn@1976 | 591 | igvn->replace_node(n, in); |
duke@435 | 592 | } |
duke@435 | 593 | else if( n->is_Region() ) { // Update all incoming edges |
duke@435 | 594 | assert( !igvn->eqv(n, this), "Must be removed from DefUse edges"); |
duke@435 | 595 | uint uses_found = 0; |
duke@435 | 596 | for( uint k=1; k < n->req(); k++ ) { |
duke@435 | 597 | if( n->in(k) == this ) { |
duke@435 | 598 | n->set_req(k, parent_ctrl); |
duke@435 | 599 | uses_found++; |
duke@435 | 600 | } |
duke@435 | 601 | } |
duke@435 | 602 | if( uses_found > 1 ) { // (--i) done at the end of the loop. |
duke@435 | 603 | i -= (uses_found - 1); |
duke@435 | 604 | } |
duke@435 | 605 | } |
duke@435 | 606 | else { |
duke@435 | 607 | assert( igvn->eqv(n->in(0), this), "Expect RegionNode to be control parent"); |
duke@435 | 608 | n->set_req(0, parent_ctrl); |
duke@435 | 609 | } |
duke@435 | 610 | #ifdef ASSERT |
duke@435 | 611 | for( uint k=0; k < n->req(); k++ ) { |
duke@435 | 612 | assert( !igvn->eqv(n->in(k), this), "All uses of RegionNode should be gone"); |
duke@435 | 613 | } |
duke@435 | 614 | #endif |
duke@435 | 615 | } |
duke@435 | 616 | // Remove the RegionNode itself from DefUse info |
duke@435 | 617 | igvn->remove_dead_node(this); |
duke@435 | 618 | return NULL; |
duke@435 | 619 | } |
duke@435 | 620 | return this; // Record progress |
duke@435 | 621 | } |
duke@435 | 622 | |
duke@435 | 623 | |
duke@435 | 624 | // If a Region flows into a Region, merge into one big happy merge. |
duke@435 | 625 | if (can_reshape) { |
duke@435 | 626 | Node *m = merge_region(this, phase); |
duke@435 | 627 | if (m != NULL) return m; |
duke@435 | 628 | } |
duke@435 | 629 | |
duke@435 | 630 | // Check if this region is the root of a clipping idiom on floats |
duke@435 | 631 | if( ConvertFloat2IntClipping && can_reshape && req() == 4 ) { |
duke@435 | 632 | // Check that only one use is a Phi and that it simplifies to two constants + |
duke@435 | 633 | PhiNode* phi = has_unique_phi(); |
duke@435 | 634 | if (phi != NULL) { // One Phi user |
duke@435 | 635 | // Check inputs to the Phi |
duke@435 | 636 | ConNode *min; |
duke@435 | 637 | ConNode *max; |
duke@435 | 638 | Node *val; |
duke@435 | 639 | uint min_idx; |
duke@435 | 640 | uint max_idx; |
duke@435 | 641 | uint val_idx; |
duke@435 | 642 | if( check_phi_clipping( phi, min, min_idx, max, max_idx, val, val_idx ) ) { |
duke@435 | 643 | IfNode *top_if; |
duke@435 | 644 | IfNode *bot_if; |
duke@435 | 645 | if( check_if_clipping( this, bot_if, top_if ) ) { |
duke@435 | 646 | // Control pattern checks, now verify compares |
duke@435 | 647 | Node *top_in = NULL; // value being compared against |
duke@435 | 648 | Node *bot_in = NULL; |
duke@435 | 649 | if( check_compare_clipping( true, bot_if, min, bot_in ) && |
duke@435 | 650 | check_compare_clipping( false, top_if, max, top_in ) ) { |
duke@435 | 651 | if( bot_in == top_in ) { |
duke@435 | 652 | PhaseIterGVN *gvn = phase->is_IterGVN(); |
duke@435 | 653 | assert( gvn != NULL, "Only had DefUse info in IterGVN"); |
duke@435 | 654 | // Only remaining check is that bot_in == top_in == (Phi's val + mods) |
duke@435 | 655 | |
duke@435 | 656 | // Check for the ConvF2INode |
duke@435 | 657 | ConvF2INode *convf2i; |
duke@435 | 658 | if( check_convf2i_clipping( phi, val_idx, convf2i, min, max ) && |
duke@435 | 659 | convf2i->in(1) == bot_in ) { |
duke@435 | 660 | // Matched pattern, including LShiftI; RShiftI, replace with integer compares |
duke@435 | 661 | // max test |
kvn@4115 | 662 | Node *cmp = gvn->register_new_node_with_optimizer(new (phase->C) CmpINode( convf2i, min )); |
kvn@4115 | 663 | Node *boo = gvn->register_new_node_with_optimizer(new (phase->C) BoolNode( cmp, BoolTest::lt )); |
kvn@4115 | 664 | IfNode *iff = (IfNode*)gvn->register_new_node_with_optimizer(new (phase->C) IfNode( top_if->in(0), boo, PROB_UNLIKELY_MAG(5), top_if->_fcnt )); |
kvn@4115 | 665 | Node *if_min= gvn->register_new_node_with_optimizer(new (phase->C) IfTrueNode (iff)); |
kvn@4115 | 666 | Node *ifF = gvn->register_new_node_with_optimizer(new (phase->C) IfFalseNode(iff)); |
duke@435 | 667 | // min test |
kvn@4115 | 668 | cmp = gvn->register_new_node_with_optimizer(new (phase->C) CmpINode( convf2i, max )); |
kvn@4115 | 669 | boo = gvn->register_new_node_with_optimizer(new (phase->C) BoolNode( cmp, BoolTest::gt )); |
kvn@4115 | 670 | iff = (IfNode*)gvn->register_new_node_with_optimizer(new (phase->C) IfNode( ifF, boo, PROB_UNLIKELY_MAG(5), bot_if->_fcnt )); |
kvn@4115 | 671 | Node *if_max= gvn->register_new_node_with_optimizer(new (phase->C) IfTrueNode (iff)); |
kvn@4115 | 672 | ifF = gvn->register_new_node_with_optimizer(new (phase->C) IfFalseNode(iff)); |
duke@435 | 673 | // update input edges to region node |
duke@435 | 674 | set_req_X( min_idx, if_min, gvn ); |
duke@435 | 675 | set_req_X( max_idx, if_max, gvn ); |
duke@435 | 676 | set_req_X( val_idx, ifF, gvn ); |
duke@435 | 677 | // remove unnecessary 'LShiftI; RShiftI' idiom |
duke@435 | 678 | gvn->hash_delete(phi); |
duke@435 | 679 | phi->set_req_X( val_idx, convf2i, gvn ); |
duke@435 | 680 | gvn->hash_find_insert(phi); |
duke@435 | 681 | // Return transformed region node |
duke@435 | 682 | return this; |
duke@435 | 683 | } |
duke@435 | 684 | } |
duke@435 | 685 | } |
duke@435 | 686 | } |
duke@435 | 687 | } |
duke@435 | 688 | } |
duke@435 | 689 | } |
duke@435 | 690 | |
duke@435 | 691 | return NULL; |
duke@435 | 692 | } |
duke@435 | 693 | |
duke@435 | 694 | |
duke@435 | 695 | |
duke@435 | 696 | const RegMask &RegionNode::out_RegMask() const { |
duke@435 | 697 | return RegMask::Empty; |
duke@435 | 698 | } |
duke@435 | 699 | |
duke@435 | 700 | // Find the one non-null required input. RegionNode only |
duke@435 | 701 | Node *Node::nonnull_req() const { |
duke@435 | 702 | assert( is_Region(), "" ); |
duke@435 | 703 | for( uint i = 1; i < _cnt; i++ ) |
duke@435 | 704 | if( in(i) ) |
duke@435 | 705 | return in(i); |
duke@435 | 706 | ShouldNotReachHere(); |
duke@435 | 707 | return NULL; |
duke@435 | 708 | } |
duke@435 | 709 | |
duke@435 | 710 | |
duke@435 | 711 | //============================================================================= |
duke@435 | 712 | // note that these functions assume that the _adr_type field is flattened |
duke@435 | 713 | uint PhiNode::hash() const { |
duke@435 | 714 | const Type* at = _adr_type; |
duke@435 | 715 | return TypeNode::hash() + (at ? at->hash() : 0); |
duke@435 | 716 | } |
duke@435 | 717 | uint PhiNode::cmp( const Node &n ) const { |
duke@435 | 718 | return TypeNode::cmp(n) && _adr_type == ((PhiNode&)n)._adr_type; |
duke@435 | 719 | } |
duke@435 | 720 | static inline |
duke@435 | 721 | const TypePtr* flatten_phi_adr_type(const TypePtr* at) { |
duke@435 | 722 | if (at == NULL || at == TypePtr::BOTTOM) return at; |
duke@435 | 723 | return Compile::current()->alias_type(at)->adr_type(); |
duke@435 | 724 | } |
duke@435 | 725 | |
duke@435 | 726 | //----------------------------make--------------------------------------------- |
duke@435 | 727 | // create a new phi with edges matching r and set (initially) to x |
duke@435 | 728 | PhiNode* PhiNode::make(Node* r, Node* x, const Type *t, const TypePtr* at) { |
duke@435 | 729 | uint preds = r->req(); // Number of predecessor paths |
duke@435 | 730 | assert(t != Type::MEMORY || at == flatten_phi_adr_type(at), "flatten at"); |
kvn@4115 | 731 | PhiNode* p = new (Compile::current()) PhiNode(r, t, at); |
duke@435 | 732 | for (uint j = 1; j < preds; j++) { |
duke@435 | 733 | // Fill in all inputs, except those which the region does not yet have |
duke@435 | 734 | if (r->in(j) != NULL) |
duke@435 | 735 | p->init_req(j, x); |
duke@435 | 736 | } |
duke@435 | 737 | return p; |
duke@435 | 738 | } |
duke@435 | 739 | PhiNode* PhiNode::make(Node* r, Node* x) { |
duke@435 | 740 | const Type* t = x->bottom_type(); |
duke@435 | 741 | const TypePtr* at = NULL; |
duke@435 | 742 | if (t == Type::MEMORY) at = flatten_phi_adr_type(x->adr_type()); |
duke@435 | 743 | return make(r, x, t, at); |
duke@435 | 744 | } |
duke@435 | 745 | PhiNode* PhiNode::make_blank(Node* r, Node* x) { |
duke@435 | 746 | const Type* t = x->bottom_type(); |
duke@435 | 747 | const TypePtr* at = NULL; |
duke@435 | 748 | if (t == Type::MEMORY) at = flatten_phi_adr_type(x->adr_type()); |
kvn@4115 | 749 | return new (Compile::current()) PhiNode(r, t, at); |
duke@435 | 750 | } |
duke@435 | 751 | |
duke@435 | 752 | |
duke@435 | 753 | //------------------------slice_memory----------------------------------------- |
duke@435 | 754 | // create a new phi with narrowed memory type |
duke@435 | 755 | PhiNode* PhiNode::slice_memory(const TypePtr* adr_type) const { |
duke@435 | 756 | PhiNode* mem = (PhiNode*) clone(); |
duke@435 | 757 | *(const TypePtr**)&mem->_adr_type = adr_type; |
duke@435 | 758 | // convert self-loops, or else we get a bad graph |
duke@435 | 759 | for (uint i = 1; i < req(); i++) { |
duke@435 | 760 | if ((const Node*)in(i) == this) mem->set_req(i, mem); |
duke@435 | 761 | } |
duke@435 | 762 | mem->verify_adr_type(); |
duke@435 | 763 | return mem; |
duke@435 | 764 | } |
duke@435 | 765 | |
kvn@509 | 766 | //------------------------split_out_instance----------------------------------- |
kvn@509 | 767 | // Split out an instance type from a bottom phi. |
kvn@509 | 768 | PhiNode* PhiNode::split_out_instance(const TypePtr* at, PhaseIterGVN *igvn) const { |
kvn@598 | 769 | const TypeOopPtr *t_oop = at->isa_oopptr(); |
kvn@658 | 770 | assert(t_oop != NULL && t_oop->is_known_instance(), "expecting instance oopptr"); |
kvn@598 | 771 | const TypePtr *t = adr_type(); |
kvn@598 | 772 | assert(type() == Type::MEMORY && |
kvn@598 | 773 | (t == TypePtr::BOTTOM || t == TypeRawPtr::BOTTOM || |
kvn@658 | 774 | t->isa_oopptr() && !t->is_oopptr()->is_known_instance() && |
kvn@682 | 775 | t->is_oopptr()->cast_to_exactness(true) |
kvn@682 | 776 | ->is_oopptr()->cast_to_ptr_type(t_oop->ptr()) |
kvn@682 | 777 | ->is_oopptr()->cast_to_instance_id(t_oop->instance_id()) == t_oop), |
kvn@598 | 778 | "bottom or raw memory required"); |
kvn@509 | 779 | |
kvn@509 | 780 | // Check if an appropriate node already exists. |
kvn@509 | 781 | Node *region = in(0); |
kvn@509 | 782 | for (DUIterator_Fast kmax, k = region->fast_outs(kmax); k < kmax; k++) { |
kvn@509 | 783 | Node* use = region->fast_out(k); |
kvn@509 | 784 | if( use->is_Phi()) { |
kvn@509 | 785 | PhiNode *phi2 = use->as_Phi(); |
kvn@509 | 786 | if (phi2->type() == Type::MEMORY && phi2->adr_type() == at) { |
kvn@509 | 787 | return phi2; |
kvn@509 | 788 | } |
kvn@509 | 789 | } |
kvn@509 | 790 | } |
kvn@509 | 791 | Compile *C = igvn->C; |
kvn@509 | 792 | Arena *a = Thread::current()->resource_area(); |
kvn@509 | 793 | Node_Array node_map = new Node_Array(a); |
kvn@509 | 794 | Node_Stack stack(a, C->unique() >> 4); |
kvn@509 | 795 | PhiNode *nphi = slice_memory(at); |
kvn@509 | 796 | igvn->register_new_node_with_optimizer( nphi ); |
kvn@509 | 797 | node_map.map(_idx, nphi); |
kvn@509 | 798 | stack.push((Node *)this, 1); |
kvn@509 | 799 | while(!stack.is_empty()) { |
kvn@509 | 800 | PhiNode *ophi = stack.node()->as_Phi(); |
kvn@509 | 801 | uint i = stack.index(); |
kvn@509 | 802 | assert(i >= 1, "not control edge"); |
kvn@509 | 803 | stack.pop(); |
kvn@509 | 804 | nphi = node_map[ophi->_idx]->as_Phi(); |
kvn@509 | 805 | for (; i < ophi->req(); i++) { |
kvn@509 | 806 | Node *in = ophi->in(i); |
kvn@509 | 807 | if (in == NULL || igvn->type(in) == Type::TOP) |
kvn@509 | 808 | continue; |
kvn@5110 | 809 | Node *opt = MemNode::optimize_simple_memory_chain(in, t_oop, NULL, igvn); |
kvn@509 | 810 | PhiNode *optphi = opt->is_Phi() ? opt->as_Phi() : NULL; |
kvn@509 | 811 | if (optphi != NULL && optphi->adr_type() == TypePtr::BOTTOM) { |
kvn@509 | 812 | opt = node_map[optphi->_idx]; |
kvn@509 | 813 | if (opt == NULL) { |
kvn@509 | 814 | stack.push(ophi, i); |
kvn@509 | 815 | nphi = optphi->slice_memory(at); |
kvn@509 | 816 | igvn->register_new_node_with_optimizer( nphi ); |
kvn@509 | 817 | node_map.map(optphi->_idx, nphi); |
kvn@509 | 818 | ophi = optphi; |
kvn@509 | 819 | i = 0; // will get incremented at top of loop |
kvn@509 | 820 | continue; |
kvn@509 | 821 | } |
kvn@509 | 822 | } |
kvn@509 | 823 | nphi->set_req(i, opt); |
kvn@509 | 824 | } |
kvn@509 | 825 | } |
kvn@509 | 826 | return nphi; |
kvn@509 | 827 | } |
kvn@509 | 828 | |
duke@435 | 829 | //------------------------verify_adr_type-------------------------------------- |
duke@435 | 830 | #ifdef ASSERT |
duke@435 | 831 | void PhiNode::verify_adr_type(VectorSet& visited, const TypePtr* at) const { |
duke@435 | 832 | if (visited.test_set(_idx)) return; //already visited |
duke@435 | 833 | |
duke@435 | 834 | // recheck constructor invariants: |
duke@435 | 835 | verify_adr_type(false); |
duke@435 | 836 | |
duke@435 | 837 | // recheck local phi/phi consistency: |
duke@435 | 838 | assert(_adr_type == at || _adr_type == TypePtr::BOTTOM, |
duke@435 | 839 | "adr_type must be consistent across phi nest"); |
duke@435 | 840 | |
duke@435 | 841 | // walk around |
duke@435 | 842 | for (uint i = 1; i < req(); i++) { |
duke@435 | 843 | Node* n = in(i); |
duke@435 | 844 | if (n == NULL) continue; |
duke@435 | 845 | const Node* np = in(i); |
duke@435 | 846 | if (np->is_Phi()) { |
duke@435 | 847 | np->as_Phi()->verify_adr_type(visited, at); |
duke@435 | 848 | } else if (n->bottom_type() == Type::TOP |
duke@435 | 849 | || (n->is_Mem() && n->in(MemNode::Address)->bottom_type() == Type::TOP)) { |
duke@435 | 850 | // ignore top inputs |
duke@435 | 851 | } else { |
duke@435 | 852 | const TypePtr* nat = flatten_phi_adr_type(n->adr_type()); |
duke@435 | 853 | // recheck phi/non-phi consistency at leaves: |
duke@435 | 854 | assert((nat != NULL) == (at != NULL), ""); |
duke@435 | 855 | assert(nat == at || nat == TypePtr::BOTTOM, |
duke@435 | 856 | "adr_type must be consistent at leaves of phi nest"); |
duke@435 | 857 | } |
duke@435 | 858 | } |
duke@435 | 859 | } |
duke@435 | 860 | |
duke@435 | 861 | // Verify a whole nest of phis rooted at this one. |
duke@435 | 862 | void PhiNode::verify_adr_type(bool recursive) const { |
duke@435 | 863 | if (is_error_reported()) return; // muzzle asserts when debugging an error |
duke@435 | 864 | if (Node::in_dump()) return; // muzzle asserts when printing |
duke@435 | 865 | |
duke@435 | 866 | assert((_type == Type::MEMORY) == (_adr_type != NULL), "adr_type for memory phis only"); |
duke@435 | 867 | |
duke@435 | 868 | if (!VerifyAliases) return; // verify thoroughly only if requested |
duke@435 | 869 | |
duke@435 | 870 | assert(_adr_type == flatten_phi_adr_type(_adr_type), |
duke@435 | 871 | "Phi::adr_type must be pre-normalized"); |
duke@435 | 872 | |
duke@435 | 873 | if (recursive) { |
duke@435 | 874 | VectorSet visited(Thread::current()->resource_area()); |
duke@435 | 875 | verify_adr_type(visited, _adr_type); |
duke@435 | 876 | } |
duke@435 | 877 | } |
duke@435 | 878 | #endif |
duke@435 | 879 | |
duke@435 | 880 | |
duke@435 | 881 | //------------------------------Value------------------------------------------ |
duke@435 | 882 | // Compute the type of the PhiNode |
duke@435 | 883 | const Type *PhiNode::Value( PhaseTransform *phase ) const { |
duke@435 | 884 | Node *r = in(0); // RegionNode |
duke@435 | 885 | if( !r ) // Copy or dead |
duke@435 | 886 | return in(1) ? phase->type(in(1)) : Type::TOP; |
duke@435 | 887 | |
duke@435 | 888 | // Note: During parsing, phis are often transformed before their regions. |
duke@435 | 889 | // This means we have to use type_or_null to defend against untyped regions. |
duke@435 | 890 | if( phase->type_or_null(r) == Type::TOP ) // Dead code? |
duke@435 | 891 | return Type::TOP; |
duke@435 | 892 | |
duke@435 | 893 | // Check for trip-counted loop. If so, be smarter. |
duke@435 | 894 | CountedLoopNode *l = r->is_CountedLoop() ? r->as_CountedLoop() : NULL; |
duke@435 | 895 | if( l && l->can_be_counted_loop(phase) && |
duke@435 | 896 | ((const Node*)l->phi() == this) ) { // Trip counted loop! |
duke@435 | 897 | // protect against init_trip() or limit() returning NULL |
duke@435 | 898 | const Node *init = l->init_trip(); |
duke@435 | 899 | const Node *limit = l->limit(); |
duke@435 | 900 | if( init != NULL && limit != NULL && l->stride_is_con() ) { |
duke@435 | 901 | const TypeInt *lo = init ->bottom_type()->isa_int(); |
duke@435 | 902 | const TypeInt *hi = limit->bottom_type()->isa_int(); |
duke@435 | 903 | if( lo && hi ) { // Dying loops might have TOP here |
duke@435 | 904 | int stride = l->stride_con(); |
duke@435 | 905 | if( stride < 0 ) { // Down-counter loop |
duke@435 | 906 | const TypeInt *tmp = lo; lo = hi; hi = tmp; |
duke@435 | 907 | stride = -stride; |
duke@435 | 908 | } |
duke@435 | 909 | if( lo->_hi < hi->_lo ) // Reversed endpoints are well defined :-( |
duke@435 | 910 | return TypeInt::make(lo->_lo,hi->_hi,3); |
duke@435 | 911 | } |
duke@435 | 912 | } |
duke@435 | 913 | } |
duke@435 | 914 | |
duke@435 | 915 | // Until we have harmony between classes and interfaces in the type |
duke@435 | 916 | // lattice, we must tread carefully around phis which implicitly |
duke@435 | 917 | // convert the one to the other. |
kvn@656 | 918 | const TypePtr* ttp = _type->make_ptr(); |
kvn@656 | 919 | const TypeInstPtr* ttip = (ttp != NULL) ? ttp->isa_instptr() : NULL; |
never@990 | 920 | const TypeKlassPtr* ttkp = (ttp != NULL) ? ttp->isa_klassptr() : NULL; |
duke@435 | 921 | bool is_intf = false; |
duke@435 | 922 | if (ttip != NULL) { |
duke@435 | 923 | ciKlass* k = ttip->klass(); |
duke@435 | 924 | if (k->is_loaded() && k->is_interface()) |
duke@435 | 925 | is_intf = true; |
duke@435 | 926 | } |
never@990 | 927 | if (ttkp != NULL) { |
never@990 | 928 | ciKlass* k = ttkp->klass(); |
never@990 | 929 | if (k->is_loaded() && k->is_interface()) |
never@990 | 930 | is_intf = true; |
never@990 | 931 | } |
duke@435 | 932 | |
duke@435 | 933 | // Default case: merge all inputs |
duke@435 | 934 | const Type *t = Type::TOP; // Merged type starting value |
duke@435 | 935 | for (uint i = 1; i < req(); ++i) {// For all paths in |
duke@435 | 936 | // Reachable control path? |
duke@435 | 937 | if (r->in(i) && phase->type(r->in(i)) == Type::CONTROL) { |
duke@435 | 938 | const Type* ti = phase->type(in(i)); |
duke@435 | 939 | // We assume that each input of an interface-valued Phi is a true |
duke@435 | 940 | // subtype of that interface. This might not be true of the meet |
duke@435 | 941 | // of all the input types. The lattice is not distributive in |
duke@435 | 942 | // such cases. Ward off asserts in type.cpp by refusing to do |
duke@435 | 943 | // meets between interfaces and proper classes. |
kvn@656 | 944 | const TypePtr* tip = ti->make_ptr(); |
kvn@656 | 945 | const TypeInstPtr* tiip = (tip != NULL) ? tip->isa_instptr() : NULL; |
duke@435 | 946 | if (tiip) { |
duke@435 | 947 | bool ti_is_intf = false; |
duke@435 | 948 | ciKlass* k = tiip->klass(); |
duke@435 | 949 | if (k->is_loaded() && k->is_interface()) |
duke@435 | 950 | ti_is_intf = true; |
duke@435 | 951 | if (is_intf != ti_is_intf) |
duke@435 | 952 | { t = _type; break; } |
duke@435 | 953 | } |
duke@435 | 954 | t = t->meet(ti); |
duke@435 | 955 | } |
duke@435 | 956 | } |
duke@435 | 957 | |
duke@435 | 958 | // The worst-case type (from ciTypeFlow) should be consistent with "t". |
duke@435 | 959 | // That is, we expect that "t->higher_equal(_type)" holds true. |
duke@435 | 960 | // There are various exceptions: |
duke@435 | 961 | // - Inputs which are phis might in fact be widened unnecessarily. |
duke@435 | 962 | // For example, an input might be a widened int while the phi is a short. |
duke@435 | 963 | // - Inputs might be BotPtrs but this phi is dependent on a null check, |
duke@435 | 964 | // and postCCP has removed the cast which encodes the result of the check. |
duke@435 | 965 | // - The type of this phi is an interface, and the inputs are classes. |
duke@435 | 966 | // - Value calls on inputs might produce fuzzy results. |
duke@435 | 967 | // (Occurrences of this case suggest improvements to Value methods.) |
duke@435 | 968 | // |
duke@435 | 969 | // It is not possible to see Type::BOTTOM values as phi inputs, |
duke@435 | 970 | // because the ciTypeFlow pre-pass produces verifier-quality types. |
duke@435 | 971 | const Type* ft = t->filter(_type); // Worst case type |
duke@435 | 972 | |
duke@435 | 973 | #ifdef ASSERT |
duke@435 | 974 | // The following logic has been moved into TypeOopPtr::filter. |
duke@435 | 975 | const Type* jt = t->join(_type); |
duke@435 | 976 | if( jt->empty() ) { // Emptied out??? |
duke@435 | 977 | |
duke@435 | 978 | // Check for evil case of 't' being a class and '_type' expecting an |
duke@435 | 979 | // interface. This can happen because the bytecodes do not contain |
duke@435 | 980 | // enough type info to distinguish a Java-level interface variable |
duke@435 | 981 | // from a Java-level object variable. If we meet 2 classes which |
duke@435 | 982 | // both implement interface I, but their meet is at 'j/l/O' which |
duke@435 | 983 | // doesn't implement I, we have no way to tell if the result should |
duke@435 | 984 | // be 'I' or 'j/l/O'. Thus we'll pick 'j/l/O'. If this then flows |
duke@435 | 985 | // into a Phi which "knows" it's an Interface type we'll have to |
duke@435 | 986 | // uplift the type. |
duke@435 | 987 | if( !t->empty() && ttip && ttip->is_loaded() && ttip->klass()->is_interface() ) |
duke@435 | 988 | { assert(ft == _type, ""); } // Uplift to interface |
never@990 | 989 | else if( !t->empty() && ttkp && ttkp->is_loaded() && ttkp->klass()->is_interface() ) |
never@990 | 990 | { assert(ft == _type, ""); } // Uplift to interface |
duke@435 | 991 | // Otherwise it's something stupid like non-overlapping int ranges |
duke@435 | 992 | // found on dying counted loops. |
duke@435 | 993 | else |
duke@435 | 994 | { assert(ft == Type::TOP, ""); } // Canonical empty value |
duke@435 | 995 | } |
duke@435 | 996 | |
duke@435 | 997 | else { |
duke@435 | 998 | |
duke@435 | 999 | // If we have an interface-typed Phi and we narrow to a class type, the join |
duke@435 | 1000 | // should report back the class. However, if we have a J/L/Object |
duke@435 | 1001 | // class-typed Phi and an interface flows in, it's possible that the meet & |
duke@435 | 1002 | // join report an interface back out. This isn't possible but happens |
duke@435 | 1003 | // because the type system doesn't interact well with interfaces. |
kvn@656 | 1004 | const TypePtr *jtp = jt->make_ptr(); |
kvn@656 | 1005 | const TypeInstPtr *jtip = (jtp != NULL) ? jtp->isa_instptr() : NULL; |
never@990 | 1006 | const TypeKlassPtr *jtkp = (jtp != NULL) ? jtp->isa_klassptr() : NULL; |
duke@435 | 1007 | if( jtip && ttip ) { |
duke@435 | 1008 | if( jtip->is_loaded() && jtip->klass()->is_interface() && |
coleenp@548 | 1009 | ttip->is_loaded() && !ttip->klass()->is_interface() ) { |
duke@435 | 1010 | // Happens in a CTW of rt.jar, 320-341, no extra flags |
coleenp@548 | 1011 | assert(ft == ttip->cast_to_ptr_type(jtip->ptr()) || |
kvn@656 | 1012 | ft->isa_narrowoop() && ft->make_ptr() == ttip->cast_to_ptr_type(jtip->ptr()), ""); |
coleenp@548 | 1013 | jt = ft; |
coleenp@548 | 1014 | } |
duke@435 | 1015 | } |
never@990 | 1016 | if( jtkp && ttkp ) { |
never@990 | 1017 | if( jtkp->is_loaded() && jtkp->klass()->is_interface() && |
kvn@1770 | 1018 | !jtkp->klass_is_exact() && // Keep exact interface klass (6894807) |
never@990 | 1019 | ttkp->is_loaded() && !ttkp->klass()->is_interface() ) { |
never@990 | 1020 | assert(ft == ttkp->cast_to_ptr_type(jtkp->ptr()) || |
never@990 | 1021 | ft->isa_narrowoop() && ft->make_ptr() == ttkp->cast_to_ptr_type(jtkp->ptr()), ""); |
never@990 | 1022 | jt = ft; |
never@990 | 1023 | } |
never@990 | 1024 | } |
duke@435 | 1025 | if (jt != ft && jt->base() == ft->base()) { |
duke@435 | 1026 | if (jt->isa_int() && |
duke@435 | 1027 | jt->is_int()->_lo == ft->is_int()->_lo && |
duke@435 | 1028 | jt->is_int()->_hi == ft->is_int()->_hi) |
duke@435 | 1029 | jt = ft; |
duke@435 | 1030 | if (jt->isa_long() && |
duke@435 | 1031 | jt->is_long()->_lo == ft->is_long()->_lo && |
duke@435 | 1032 | jt->is_long()->_hi == ft->is_long()->_hi) |
duke@435 | 1033 | jt = ft; |
duke@435 | 1034 | } |
duke@435 | 1035 | if (jt != ft) { |
duke@435 | 1036 | tty->print("merge type: "); t->dump(); tty->cr(); |
duke@435 | 1037 | tty->print("kill type: "); _type->dump(); tty->cr(); |
duke@435 | 1038 | tty->print("join type: "); jt->dump(); tty->cr(); |
duke@435 | 1039 | tty->print("filter type: "); ft->dump(); tty->cr(); |
duke@435 | 1040 | } |
duke@435 | 1041 | assert(jt == ft, ""); |
duke@435 | 1042 | } |
duke@435 | 1043 | #endif //ASSERT |
duke@435 | 1044 | |
duke@435 | 1045 | // Deal with conversion problems found in data loops. |
duke@435 | 1046 | ft = phase->saturate(ft, phase->type_or_null(this), _type); |
duke@435 | 1047 | |
duke@435 | 1048 | return ft; |
duke@435 | 1049 | } |
duke@435 | 1050 | |
duke@435 | 1051 | |
duke@435 | 1052 | //------------------------------is_diamond_phi--------------------------------- |
duke@435 | 1053 | // Does this Phi represent a simple well-shaped diamond merge? Return the |
duke@435 | 1054 | // index of the true path or 0 otherwise. |
roland@4409 | 1055 | // If check_control_only is true, do not inspect the If node at the |
roland@4409 | 1056 | // top, and return -1 (not an edge number) on success. |
roland@4409 | 1057 | int PhiNode::is_diamond_phi(bool check_control_only) const { |
duke@435 | 1058 | // Check for a 2-path merge |
duke@435 | 1059 | Node *region = in(0); |
duke@435 | 1060 | if( !region ) return 0; |
duke@435 | 1061 | if( region->req() != 3 ) return 0; |
duke@435 | 1062 | if( req() != 3 ) return 0; |
duke@435 | 1063 | // Check that both paths come from the same If |
duke@435 | 1064 | Node *ifp1 = region->in(1); |
duke@435 | 1065 | Node *ifp2 = region->in(2); |
duke@435 | 1066 | if( !ifp1 || !ifp2 ) return 0; |
duke@435 | 1067 | Node *iff = ifp1->in(0); |
duke@435 | 1068 | if( !iff || !iff->is_If() ) return 0; |
duke@435 | 1069 | if( iff != ifp2->in(0) ) return 0; |
roland@4409 | 1070 | if (check_control_only) return -1; |
duke@435 | 1071 | // Check for a proper bool/cmp |
duke@435 | 1072 | const Node *b = iff->in(1); |
duke@435 | 1073 | if( !b->is_Bool() ) return 0; |
duke@435 | 1074 | const Node *cmp = b->in(1); |
duke@435 | 1075 | if( !cmp->is_Cmp() ) return 0; |
duke@435 | 1076 | |
duke@435 | 1077 | // Check for branching opposite expected |
duke@435 | 1078 | if( ifp2->Opcode() == Op_IfTrue ) { |
duke@435 | 1079 | assert( ifp1->Opcode() == Op_IfFalse, "" ); |
duke@435 | 1080 | return 2; |
duke@435 | 1081 | } else { |
duke@435 | 1082 | assert( ifp1->Opcode() == Op_IfTrue, "" ); |
duke@435 | 1083 | return 1; |
duke@435 | 1084 | } |
duke@435 | 1085 | } |
duke@435 | 1086 | |
duke@435 | 1087 | //----------------------------check_cmove_id----------------------------------- |
duke@435 | 1088 | // Check for CMove'ing a constant after comparing against the constant. |
duke@435 | 1089 | // Happens all the time now, since if we compare equality vs a constant in |
duke@435 | 1090 | // the parser, we "know" the variable is constant on one path and we force |
duke@435 | 1091 | // it. Thus code like "if( x==0 ) {/*EMPTY*/}" ends up inserting a |
duke@435 | 1092 | // conditional move: "x = (x==0)?0:x;". Yucko. This fix is slightly more |
duke@435 | 1093 | // general in that we don't need constants. Since CMove's are only inserted |
duke@435 | 1094 | // in very special circumstances, we do it here on generic Phi's. |
duke@435 | 1095 | Node* PhiNode::is_cmove_id(PhaseTransform* phase, int true_path) { |
duke@435 | 1096 | assert(true_path !=0, "only diamond shape graph expected"); |
duke@435 | 1097 | |
duke@435 | 1098 | // is_diamond_phi() has guaranteed the correctness of the nodes sequence: |
duke@435 | 1099 | // phi->region->if_proj->ifnode->bool->cmp |
duke@435 | 1100 | Node* region = in(0); |
duke@435 | 1101 | Node* iff = region->in(1)->in(0); |
duke@435 | 1102 | BoolNode* b = iff->in(1)->as_Bool(); |
duke@435 | 1103 | Node* cmp = b->in(1); |
duke@435 | 1104 | Node* tval = in(true_path); |
duke@435 | 1105 | Node* fval = in(3-true_path); |
duke@435 | 1106 | Node* id = CMoveNode::is_cmove_id(phase, cmp, tval, fval, b); |
duke@435 | 1107 | if (id == NULL) |
duke@435 | 1108 | return NULL; |
duke@435 | 1109 | |
duke@435 | 1110 | // Either value might be a cast that depends on a branch of 'iff'. |
duke@435 | 1111 | // Since the 'id' value will float free of the diamond, either |
duke@435 | 1112 | // decast or return failure. |
duke@435 | 1113 | Node* ctl = id->in(0); |
duke@435 | 1114 | if (ctl != NULL && ctl->in(0) == iff) { |
duke@435 | 1115 | if (id->is_ConstraintCast()) { |
duke@435 | 1116 | return id->in(1); |
duke@435 | 1117 | } else { |
duke@435 | 1118 | // Don't know how to disentangle this value. |
duke@435 | 1119 | return NULL; |
duke@435 | 1120 | } |
duke@435 | 1121 | } |
duke@435 | 1122 | |
duke@435 | 1123 | return id; |
duke@435 | 1124 | } |
duke@435 | 1125 | |
duke@435 | 1126 | //------------------------------Identity--------------------------------------- |
duke@435 | 1127 | // Check for Region being Identity. |
duke@435 | 1128 | Node *PhiNode::Identity( PhaseTransform *phase ) { |
duke@435 | 1129 | // Check for no merging going on |
duke@435 | 1130 | // (There used to be special-case code here when this->region->is_Loop. |
duke@435 | 1131 | // It would check for a tributary phi on the backedge that the main phi |
duke@435 | 1132 | // trivially, perhaps with a single cast. The unique_input method |
duke@435 | 1133 | // does all this and more, by reducing such tributaries to 'this'.) |
duke@435 | 1134 | Node* uin = unique_input(phase); |
duke@435 | 1135 | if (uin != NULL) { |
duke@435 | 1136 | return uin; |
duke@435 | 1137 | } |
duke@435 | 1138 | |
duke@435 | 1139 | int true_path = is_diamond_phi(); |
duke@435 | 1140 | if (true_path != 0) { |
duke@435 | 1141 | Node* id = is_cmove_id(phase, true_path); |
duke@435 | 1142 | if (id != NULL) return id; |
duke@435 | 1143 | } |
duke@435 | 1144 | |
duke@435 | 1145 | return this; // No identity |
duke@435 | 1146 | } |
duke@435 | 1147 | |
duke@435 | 1148 | //-----------------------------unique_input------------------------------------ |
duke@435 | 1149 | // Find the unique value, discounting top, self-loops, and casts. |
duke@435 | 1150 | // Return top if there are no inputs, and self if there are multiple. |
duke@435 | 1151 | Node* PhiNode::unique_input(PhaseTransform* phase) { |
duke@435 | 1152 | // 1) One unique direct input, or |
duke@435 | 1153 | // 2) some of the inputs have an intervening ConstraintCast and |
duke@435 | 1154 | // the type of input is the same or sharper (more specific) |
duke@435 | 1155 | // than the phi's type. |
duke@435 | 1156 | // 3) an input is a self loop |
duke@435 | 1157 | // |
duke@435 | 1158 | // 1) input or 2) input or 3) input __ |
duke@435 | 1159 | // / \ / \ \ / \ |
duke@435 | 1160 | // \ / | cast phi cast |
duke@435 | 1161 | // phi \ / / \ / |
duke@435 | 1162 | // phi / -- |
duke@435 | 1163 | |
duke@435 | 1164 | Node* r = in(0); // RegionNode |
duke@435 | 1165 | if (r == NULL) return in(1); // Already degraded to a Copy |
duke@435 | 1166 | Node* uncasted_input = NULL; // The unique uncasted input (ConstraintCasts removed) |
duke@435 | 1167 | Node* direct_input = NULL; // The unique direct input |
duke@435 | 1168 | |
duke@435 | 1169 | for (uint i = 1, cnt = req(); i < cnt; ++i) { |
duke@435 | 1170 | Node* rc = r->in(i); |
duke@435 | 1171 | if (rc == NULL || phase->type(rc) == Type::TOP) |
duke@435 | 1172 | continue; // ignore unreachable control path |
duke@435 | 1173 | Node* n = in(i); |
kvn@682 | 1174 | if (n == NULL) |
kvn@682 | 1175 | continue; |
duke@435 | 1176 | Node* un = n->uncast(); |
duke@435 | 1177 | if (un == NULL || un == this || phase->type(un) == Type::TOP) { |
duke@435 | 1178 | continue; // ignore if top, or in(i) and "this" are in a data cycle |
duke@435 | 1179 | } |
duke@435 | 1180 | // Check for a unique uncasted input |
duke@435 | 1181 | if (uncasted_input == NULL) { |
duke@435 | 1182 | uncasted_input = un; |
duke@435 | 1183 | } else if (uncasted_input != un) { |
duke@435 | 1184 | uncasted_input = NodeSentinel; // no unique uncasted input |
duke@435 | 1185 | } |
duke@435 | 1186 | // Check for a unique direct input |
duke@435 | 1187 | if (direct_input == NULL) { |
duke@435 | 1188 | direct_input = n; |
duke@435 | 1189 | } else if (direct_input != n) { |
duke@435 | 1190 | direct_input = NodeSentinel; // no unique direct input |
duke@435 | 1191 | } |
duke@435 | 1192 | } |
duke@435 | 1193 | if (direct_input == NULL) { |
duke@435 | 1194 | return phase->C->top(); // no inputs |
duke@435 | 1195 | } |
duke@435 | 1196 | assert(uncasted_input != NULL,""); |
duke@435 | 1197 | |
duke@435 | 1198 | if (direct_input != NodeSentinel) { |
duke@435 | 1199 | return direct_input; // one unique direct input |
duke@435 | 1200 | } |
duke@435 | 1201 | if (uncasted_input != NodeSentinel && |
duke@435 | 1202 | phase->type(uncasted_input)->higher_equal(type())) { |
duke@435 | 1203 | return uncasted_input; // one unique uncasted input |
duke@435 | 1204 | } |
duke@435 | 1205 | |
duke@435 | 1206 | // Nothing. |
duke@435 | 1207 | return NULL; |
duke@435 | 1208 | } |
duke@435 | 1209 | |
duke@435 | 1210 | //------------------------------is_x2logic------------------------------------- |
duke@435 | 1211 | // Check for simple convert-to-boolean pattern |
duke@435 | 1212 | // If:(C Bool) Region:(IfF IfT) Phi:(Region 0 1) |
duke@435 | 1213 | // Convert Phi to an ConvIB. |
duke@435 | 1214 | static Node *is_x2logic( PhaseGVN *phase, PhiNode *phi, int true_path ) { |
duke@435 | 1215 | assert(true_path !=0, "only diamond shape graph expected"); |
duke@435 | 1216 | // Convert the true/false index into an expected 0/1 return. |
duke@435 | 1217 | // Map 2->0 and 1->1. |
duke@435 | 1218 | int flipped = 2-true_path; |
duke@435 | 1219 | |
duke@435 | 1220 | // is_diamond_phi() has guaranteed the correctness of the nodes sequence: |
duke@435 | 1221 | // phi->region->if_proj->ifnode->bool->cmp |
duke@435 | 1222 | Node *region = phi->in(0); |
duke@435 | 1223 | Node *iff = region->in(1)->in(0); |
duke@435 | 1224 | BoolNode *b = (BoolNode*)iff->in(1); |
duke@435 | 1225 | const CmpNode *cmp = (CmpNode*)b->in(1); |
duke@435 | 1226 | |
duke@435 | 1227 | Node *zero = phi->in(1); |
duke@435 | 1228 | Node *one = phi->in(2); |
duke@435 | 1229 | const Type *tzero = phase->type( zero ); |
duke@435 | 1230 | const Type *tone = phase->type( one ); |
duke@435 | 1231 | |
duke@435 | 1232 | // Check for compare vs 0 |
duke@435 | 1233 | const Type *tcmp = phase->type(cmp->in(2)); |
duke@435 | 1234 | if( tcmp != TypeInt::ZERO && tcmp != TypePtr::NULL_PTR ) { |
duke@435 | 1235 | // Allow cmp-vs-1 if the other input is bounded by 0-1 |
duke@435 | 1236 | if( !(tcmp == TypeInt::ONE && phase->type(cmp->in(1)) == TypeInt::BOOL) ) |
duke@435 | 1237 | return NULL; |
duke@435 | 1238 | flipped = 1-flipped; // Test is vs 1 instead of 0! |
duke@435 | 1239 | } |
duke@435 | 1240 | |
duke@435 | 1241 | // Check for setting zero/one opposite expected |
duke@435 | 1242 | if( tzero == TypeInt::ZERO ) { |
duke@435 | 1243 | if( tone == TypeInt::ONE ) { |
duke@435 | 1244 | } else return NULL; |
duke@435 | 1245 | } else if( tzero == TypeInt::ONE ) { |
duke@435 | 1246 | if( tone == TypeInt::ZERO ) { |
duke@435 | 1247 | flipped = 1-flipped; |
duke@435 | 1248 | } else return NULL; |
duke@435 | 1249 | } else return NULL; |
duke@435 | 1250 | |
duke@435 | 1251 | // Check for boolean test backwards |
duke@435 | 1252 | if( b->_test._test == BoolTest::ne ) { |
duke@435 | 1253 | } else if( b->_test._test == BoolTest::eq ) { |
duke@435 | 1254 | flipped = 1-flipped; |
duke@435 | 1255 | } else return NULL; |
duke@435 | 1256 | |
duke@435 | 1257 | // Build int->bool conversion |
kvn@4115 | 1258 | Node *n = new (phase->C) Conv2BNode( cmp->in(1) ); |
duke@435 | 1259 | if( flipped ) |
kvn@4115 | 1260 | n = new (phase->C) XorINode( phase->transform(n), phase->intcon(1) ); |
duke@435 | 1261 | |
duke@435 | 1262 | return n; |
duke@435 | 1263 | } |
duke@435 | 1264 | |
duke@435 | 1265 | //------------------------------is_cond_add------------------------------------ |
duke@435 | 1266 | // Check for simple conditional add pattern: "(P < Q) ? X+Y : X;" |
duke@435 | 1267 | // To be profitable the control flow has to disappear; there can be no other |
duke@435 | 1268 | // values merging here. We replace the test-and-branch with: |
duke@435 | 1269 | // "(sgn(P-Q))&Y) + X". Basically, convert "(P < Q)" into 0 or -1 by |
duke@435 | 1270 | // moving the carry bit from (P-Q) into a register with 'sbb EAX,EAX'. |
duke@435 | 1271 | // Then convert Y to 0-or-Y and finally add. |
duke@435 | 1272 | // This is a key transform for SpecJava _201_compress. |
duke@435 | 1273 | static Node* is_cond_add(PhaseGVN *phase, PhiNode *phi, int true_path) { |
duke@435 | 1274 | assert(true_path !=0, "only diamond shape graph expected"); |
duke@435 | 1275 | |
duke@435 | 1276 | // is_diamond_phi() has guaranteed the correctness of the nodes sequence: |
duke@435 | 1277 | // phi->region->if_proj->ifnode->bool->cmp |
duke@435 | 1278 | RegionNode *region = (RegionNode*)phi->in(0); |
duke@435 | 1279 | Node *iff = region->in(1)->in(0); |
duke@435 | 1280 | BoolNode* b = iff->in(1)->as_Bool(); |
duke@435 | 1281 | const CmpNode *cmp = (CmpNode*)b->in(1); |
duke@435 | 1282 | |
duke@435 | 1283 | // Make sure only merging this one phi here |
duke@435 | 1284 | if (region->has_unique_phi() != phi) return NULL; |
duke@435 | 1285 | |
duke@435 | 1286 | // Make sure each arm of the diamond has exactly one output, which we assume |
duke@435 | 1287 | // is the region. Otherwise, the control flow won't disappear. |
duke@435 | 1288 | if (region->in(1)->outcnt() != 1) return NULL; |
duke@435 | 1289 | if (region->in(2)->outcnt() != 1) return NULL; |
duke@435 | 1290 | |
duke@435 | 1291 | // Check for "(P < Q)" of type signed int |
duke@435 | 1292 | if (b->_test._test != BoolTest::lt) return NULL; |
duke@435 | 1293 | if (cmp->Opcode() != Op_CmpI) return NULL; |
duke@435 | 1294 | |
duke@435 | 1295 | Node *p = cmp->in(1); |
duke@435 | 1296 | Node *q = cmp->in(2); |
duke@435 | 1297 | Node *n1 = phi->in( true_path); |
duke@435 | 1298 | Node *n2 = phi->in(3-true_path); |
duke@435 | 1299 | |
duke@435 | 1300 | int op = n1->Opcode(); |
duke@435 | 1301 | if( op != Op_AddI // Need zero as additive identity |
duke@435 | 1302 | /*&&op != Op_SubI && |
duke@435 | 1303 | op != Op_AddP && |
duke@435 | 1304 | op != Op_XorI && |
duke@435 | 1305 | op != Op_OrI*/ ) |
duke@435 | 1306 | return NULL; |
duke@435 | 1307 | |
duke@435 | 1308 | Node *x = n2; |
drchase@4944 | 1309 | Node *y = NULL; |
drchase@4944 | 1310 | if( x == n1->in(1) ) { |
duke@435 | 1311 | y = n1->in(2); |
drchase@4944 | 1312 | } else if( x == n1->in(2) ) { |
drchase@4944 | 1313 | y = n1->in(1); |
duke@435 | 1314 | } else return NULL; |
duke@435 | 1315 | |
duke@435 | 1316 | // Not so profitable if compare and add are constants |
duke@435 | 1317 | if( q->is_Con() && phase->type(q) != TypeInt::ZERO && y->is_Con() ) |
duke@435 | 1318 | return NULL; |
duke@435 | 1319 | |
kvn@4115 | 1320 | Node *cmplt = phase->transform( new (phase->C) CmpLTMaskNode(p,q) ); |
kvn@4115 | 1321 | Node *j_and = phase->transform( new (phase->C) AndINode(cmplt,y) ); |
kvn@4115 | 1322 | return new (phase->C) AddINode(j_and,x); |
duke@435 | 1323 | } |
duke@435 | 1324 | |
duke@435 | 1325 | //------------------------------is_absolute------------------------------------ |
duke@435 | 1326 | // Check for absolute value. |
duke@435 | 1327 | static Node* is_absolute( PhaseGVN *phase, PhiNode *phi_root, int true_path) { |
duke@435 | 1328 | assert(true_path !=0, "only diamond shape graph expected"); |
duke@435 | 1329 | |
duke@435 | 1330 | int cmp_zero_idx = 0; // Index of compare input where to look for zero |
duke@435 | 1331 | int phi_x_idx = 0; // Index of phi input where to find naked x |
duke@435 | 1332 | |
duke@435 | 1333 | // ABS ends with the merge of 2 control flow paths. |
duke@435 | 1334 | // Find the false path from the true path. With only 2 inputs, 3 - x works nicely. |
duke@435 | 1335 | int false_path = 3 - true_path; |
duke@435 | 1336 | |
duke@435 | 1337 | // is_diamond_phi() has guaranteed the correctness of the nodes sequence: |
duke@435 | 1338 | // phi->region->if_proj->ifnode->bool->cmp |
duke@435 | 1339 | BoolNode *bol = phi_root->in(0)->in(1)->in(0)->in(1)->as_Bool(); |
duke@435 | 1340 | |
duke@435 | 1341 | // Check bool sense |
duke@435 | 1342 | switch( bol->_test._test ) { |
duke@435 | 1343 | case BoolTest::lt: cmp_zero_idx = 1; phi_x_idx = true_path; break; |
duke@435 | 1344 | case BoolTest::le: cmp_zero_idx = 2; phi_x_idx = false_path; break; |
duke@435 | 1345 | case BoolTest::gt: cmp_zero_idx = 2; phi_x_idx = true_path; break; |
duke@435 | 1346 | case BoolTest::ge: cmp_zero_idx = 1; phi_x_idx = false_path; break; |
duke@435 | 1347 | default: return NULL; break; |
duke@435 | 1348 | } |
duke@435 | 1349 | |
duke@435 | 1350 | // Test is next |
duke@435 | 1351 | Node *cmp = bol->in(1); |
duke@435 | 1352 | const Type *tzero = NULL; |
duke@435 | 1353 | switch( cmp->Opcode() ) { |
duke@435 | 1354 | case Op_CmpF: tzero = TypeF::ZERO; break; // Float ABS |
duke@435 | 1355 | case Op_CmpD: tzero = TypeD::ZERO; break; // Double ABS |
duke@435 | 1356 | default: return NULL; |
duke@435 | 1357 | } |
duke@435 | 1358 | |
duke@435 | 1359 | // Find zero input of compare; the other input is being abs'd |
duke@435 | 1360 | Node *x = NULL; |
duke@435 | 1361 | bool flip = false; |
duke@435 | 1362 | if( phase->type(cmp->in(cmp_zero_idx)) == tzero ) { |
duke@435 | 1363 | x = cmp->in(3 - cmp_zero_idx); |
duke@435 | 1364 | } else if( phase->type(cmp->in(3 - cmp_zero_idx)) == tzero ) { |
duke@435 | 1365 | // The test is inverted, we should invert the result... |
duke@435 | 1366 | x = cmp->in(cmp_zero_idx); |
duke@435 | 1367 | flip = true; |
duke@435 | 1368 | } else { |
duke@435 | 1369 | return NULL; |
duke@435 | 1370 | } |
duke@435 | 1371 | |
duke@435 | 1372 | // Next get the 2 pieces being selected, one is the original value |
duke@435 | 1373 | // and the other is the negated value. |
duke@435 | 1374 | if( phi_root->in(phi_x_idx) != x ) return NULL; |
duke@435 | 1375 | |
duke@435 | 1376 | // Check other phi input for subtract node |
duke@435 | 1377 | Node *sub = phi_root->in(3 - phi_x_idx); |
duke@435 | 1378 | |
duke@435 | 1379 | // Allow only Sub(0,X) and fail out for all others; Neg is not OK |
duke@435 | 1380 | if( tzero == TypeF::ZERO ) { |
duke@435 | 1381 | if( sub->Opcode() != Op_SubF || |
duke@435 | 1382 | sub->in(2) != x || |
duke@435 | 1383 | phase->type(sub->in(1)) != tzero ) return NULL; |
kvn@4115 | 1384 | x = new (phase->C) AbsFNode(x); |
duke@435 | 1385 | if (flip) { |
kvn@4115 | 1386 | x = new (phase->C) SubFNode(sub->in(1), phase->transform(x)); |
duke@435 | 1387 | } |
duke@435 | 1388 | } else { |
duke@435 | 1389 | if( sub->Opcode() != Op_SubD || |
duke@435 | 1390 | sub->in(2) != x || |
duke@435 | 1391 | phase->type(sub->in(1)) != tzero ) return NULL; |
kvn@4115 | 1392 | x = new (phase->C) AbsDNode(x); |
duke@435 | 1393 | if (flip) { |
kvn@4115 | 1394 | x = new (phase->C) SubDNode(sub->in(1), phase->transform(x)); |
duke@435 | 1395 | } |
duke@435 | 1396 | } |
duke@435 | 1397 | |
duke@435 | 1398 | return x; |
duke@435 | 1399 | } |
duke@435 | 1400 | |
duke@435 | 1401 | //------------------------------split_once------------------------------------- |
duke@435 | 1402 | // Helper for split_flow_path |
duke@435 | 1403 | static void split_once(PhaseIterGVN *igvn, Node *phi, Node *val, Node *n, Node *newn) { |
duke@435 | 1404 | igvn->hash_delete(n); // Remove from hash before hacking edges |
duke@435 | 1405 | |
duke@435 | 1406 | uint j = 1; |
kvn@2727 | 1407 | for (uint i = phi->req()-1; i > 0; i--) { |
kvn@2727 | 1408 | if (phi->in(i) == val) { // Found a path with val? |
duke@435 | 1409 | // Add to NEW Region/Phi, no DU info |
duke@435 | 1410 | newn->set_req( j++, n->in(i) ); |
duke@435 | 1411 | // Remove from OLD Region/Phi |
duke@435 | 1412 | n->del_req(i); |
duke@435 | 1413 | } |
duke@435 | 1414 | } |
duke@435 | 1415 | |
duke@435 | 1416 | // Register the new node but do not transform it. Cannot transform until the |
twisti@1040 | 1417 | // entire Region/Phi conglomerate has been hacked as a single huge transform. |
duke@435 | 1418 | igvn->register_new_node_with_optimizer( newn ); |
kvn@2727 | 1419 | |
duke@435 | 1420 | // Now I can point to the new node. |
duke@435 | 1421 | n->add_req(newn); |
duke@435 | 1422 | igvn->_worklist.push(n); |
duke@435 | 1423 | } |
duke@435 | 1424 | |
duke@435 | 1425 | //------------------------------split_flow_path-------------------------------- |
duke@435 | 1426 | // Check for merging identical values and split flow paths |
duke@435 | 1427 | static Node* split_flow_path(PhaseGVN *phase, PhiNode *phi) { |
duke@435 | 1428 | BasicType bt = phi->type()->basic_type(); |
duke@435 | 1429 | if( bt == T_ILLEGAL || type2size[bt] <= 0 ) |
duke@435 | 1430 | return NULL; // Bail out on funny non-value stuff |
duke@435 | 1431 | if( phi->req() <= 3 ) // Need at least 2 matched inputs and a |
duke@435 | 1432 | return NULL; // third unequal input to be worth doing |
duke@435 | 1433 | |
duke@435 | 1434 | // Scan for a constant |
duke@435 | 1435 | uint i; |
duke@435 | 1436 | for( i = 1; i < phi->req()-1; i++ ) { |
duke@435 | 1437 | Node *n = phi->in(i); |
duke@435 | 1438 | if( !n ) return NULL; |
duke@435 | 1439 | if( phase->type(n) == Type::TOP ) return NULL; |
roland@4159 | 1440 | if( n->Opcode() == Op_ConP || n->Opcode() == Op_ConN || n->Opcode() == Op_ConNKlass ) |
duke@435 | 1441 | break; |
duke@435 | 1442 | } |
duke@435 | 1443 | if( i >= phi->req() ) // Only split for constants |
duke@435 | 1444 | return NULL; |
duke@435 | 1445 | |
duke@435 | 1446 | Node *val = phi->in(i); // Constant to split for |
duke@435 | 1447 | uint hit = 0; // Number of times it occurs |
kvn@3043 | 1448 | Node *r = phi->region(); |
duke@435 | 1449 | |
twisti@1040 | 1450 | for( ; i < phi->req(); i++ ){ // Count occurrences of constant |
duke@435 | 1451 | Node *n = phi->in(i); |
duke@435 | 1452 | if( !n ) return NULL; |
duke@435 | 1453 | if( phase->type(n) == Type::TOP ) return NULL; |
kvn@3043 | 1454 | if( phi->in(i) == val ) { |
duke@435 | 1455 | hit++; |
kvn@3043 | 1456 | if (PhaseIdealLoop::find_predicate(r->in(i)) != NULL) { |
kvn@3043 | 1457 | return NULL; // don't split loop entry path |
kvn@3043 | 1458 | } |
kvn@3043 | 1459 | } |
duke@435 | 1460 | } |
duke@435 | 1461 | |
duke@435 | 1462 | if( hit <= 1 || // Make sure we find 2 or more |
duke@435 | 1463 | hit == phi->req()-1 ) // and not ALL the same value |
duke@435 | 1464 | return NULL; |
duke@435 | 1465 | |
duke@435 | 1466 | // Now start splitting out the flow paths that merge the same value. |
duke@435 | 1467 | // Split first the RegionNode. |
duke@435 | 1468 | PhaseIterGVN *igvn = phase->is_IterGVN(); |
kvn@4115 | 1469 | RegionNode *newr = new (phase->C) RegionNode(hit+1); |
duke@435 | 1470 | split_once(igvn, phi, val, r, newr); |
duke@435 | 1471 | |
duke@435 | 1472 | // Now split all other Phis than this one |
duke@435 | 1473 | for (DUIterator_Fast kmax, k = r->fast_outs(kmax); k < kmax; k++) { |
duke@435 | 1474 | Node* phi2 = r->fast_out(k); |
duke@435 | 1475 | if( phi2->is_Phi() && phi2->as_Phi() != phi ) { |
duke@435 | 1476 | PhiNode *newphi = PhiNode::make_blank(newr, phi2); |
duke@435 | 1477 | split_once(igvn, phi, val, phi2, newphi); |
duke@435 | 1478 | } |
duke@435 | 1479 | } |
duke@435 | 1480 | |
duke@435 | 1481 | // Clean up this guy |
duke@435 | 1482 | igvn->hash_delete(phi); |
duke@435 | 1483 | for( i = phi->req()-1; i > 0; i-- ) { |
duke@435 | 1484 | if( phi->in(i) == val ) { |
duke@435 | 1485 | phi->del_req(i); |
duke@435 | 1486 | } |
duke@435 | 1487 | } |
duke@435 | 1488 | phi->add_req(val); |
duke@435 | 1489 | |
duke@435 | 1490 | return phi; |
duke@435 | 1491 | } |
duke@435 | 1492 | |
duke@435 | 1493 | //============================================================================= |
duke@435 | 1494 | //------------------------------simple_data_loop_check------------------------- |
twisti@1040 | 1495 | // Try to determining if the phi node in a simple safe/unsafe data loop. |
duke@435 | 1496 | // Returns: |
duke@435 | 1497 | // enum LoopSafety { Safe = 0, Unsafe, UnsafeLoop }; |
duke@435 | 1498 | // Safe - safe case when the phi and it's inputs reference only safe data |
duke@435 | 1499 | // nodes; |
duke@435 | 1500 | // Unsafe - the phi and it's inputs reference unsafe data nodes but there |
duke@435 | 1501 | // is no reference back to the phi - need a graph walk |
duke@435 | 1502 | // to determine if it is in a loop; |
duke@435 | 1503 | // UnsafeLoop - unsafe case when the phi references itself directly or through |
duke@435 | 1504 | // unsafe data node. |
duke@435 | 1505 | // Note: a safe data node is a node which could/never reference itself during |
duke@435 | 1506 | // GVN transformations. For now it is Con, Proj, Phi, CastPP, CheckCastPP. |
duke@435 | 1507 | // I mark Phi nodes as safe node not only because they can reference itself |
duke@435 | 1508 | // but also to prevent mistaking the fallthrough case inside an outer loop |
duke@435 | 1509 | // as dead loop when the phi references itselfs through an other phi. |
duke@435 | 1510 | PhiNode::LoopSafety PhiNode::simple_data_loop_check(Node *in) const { |
duke@435 | 1511 | // It is unsafe loop if the phi node references itself directly. |
duke@435 | 1512 | if (in == (Node*)this) |
duke@435 | 1513 | return UnsafeLoop; // Unsafe loop |
duke@435 | 1514 | // Unsafe loop if the phi node references itself through an unsafe data node. |
duke@435 | 1515 | // Exclude cases with null inputs or data nodes which could reference |
duke@435 | 1516 | // itself (safe for dead loops). |
duke@435 | 1517 | if (in != NULL && !in->is_dead_loop_safe()) { |
duke@435 | 1518 | // Check inputs of phi's inputs also. |
duke@435 | 1519 | // It is much less expensive then full graph walk. |
duke@435 | 1520 | uint cnt = in->req(); |
kvn@561 | 1521 | uint i = (in->is_Proj() && !in->is_CFG()) ? 0 : 1; |
kvn@561 | 1522 | for (; i < cnt; ++i) { |
duke@435 | 1523 | Node* m = in->in(i); |
duke@435 | 1524 | if (m == (Node*)this) |
duke@435 | 1525 | return UnsafeLoop; // Unsafe loop |
duke@435 | 1526 | if (m != NULL && !m->is_dead_loop_safe()) { |
duke@435 | 1527 | // Check the most common case (about 30% of all cases): |
duke@435 | 1528 | // phi->Load/Store->AddP->(ConP ConP Con)/(Parm Parm Con). |
duke@435 | 1529 | Node *m1 = (m->is_AddP() && m->req() > 3) ? m->in(1) : NULL; |
duke@435 | 1530 | if (m1 == (Node*)this) |
duke@435 | 1531 | return UnsafeLoop; // Unsafe loop |
duke@435 | 1532 | if (m1 != NULL && m1 == m->in(2) && |
duke@435 | 1533 | m1->is_dead_loop_safe() && m->in(3)->is_Con()) { |
duke@435 | 1534 | continue; // Safe case |
duke@435 | 1535 | } |
duke@435 | 1536 | // The phi references an unsafe node - need full analysis. |
duke@435 | 1537 | return Unsafe; |
duke@435 | 1538 | } |
duke@435 | 1539 | } |
duke@435 | 1540 | } |
duke@435 | 1541 | return Safe; // Safe case - we can optimize the phi node. |
duke@435 | 1542 | } |
duke@435 | 1543 | |
duke@435 | 1544 | //------------------------------is_unsafe_data_reference----------------------- |
duke@435 | 1545 | // If phi can be reached through the data input - it is data loop. |
duke@435 | 1546 | bool PhiNode::is_unsafe_data_reference(Node *in) const { |
duke@435 | 1547 | assert(req() > 1, ""); |
duke@435 | 1548 | // First, check simple cases when phi references itself directly or |
duke@435 | 1549 | // through an other node. |
duke@435 | 1550 | LoopSafety safety = simple_data_loop_check(in); |
duke@435 | 1551 | if (safety == UnsafeLoop) |
duke@435 | 1552 | return true; // phi references itself - unsafe loop |
duke@435 | 1553 | else if (safety == Safe) |
duke@435 | 1554 | return false; // Safe case - phi could be replaced with the unique input. |
duke@435 | 1555 | |
duke@435 | 1556 | // Unsafe case when we should go through data graph to determine |
duke@435 | 1557 | // if the phi references itself. |
duke@435 | 1558 | |
duke@435 | 1559 | ResourceMark rm; |
duke@435 | 1560 | |
duke@435 | 1561 | Arena *a = Thread::current()->resource_area(); |
duke@435 | 1562 | Node_List nstack(a); |
duke@435 | 1563 | VectorSet visited(a); |
duke@435 | 1564 | |
duke@435 | 1565 | nstack.push(in); // Start with unique input. |
duke@435 | 1566 | visited.set(in->_idx); |
duke@435 | 1567 | while (nstack.size() != 0) { |
duke@435 | 1568 | Node* n = nstack.pop(); |
duke@435 | 1569 | uint cnt = n->req(); |
kvn@561 | 1570 | uint i = (n->is_Proj() && !n->is_CFG()) ? 0 : 1; |
kvn@561 | 1571 | for (; i < cnt; i++) { |
duke@435 | 1572 | Node* m = n->in(i); |
duke@435 | 1573 | if (m == (Node*)this) { |
duke@435 | 1574 | return true; // Data loop |
duke@435 | 1575 | } |
duke@435 | 1576 | if (m != NULL && !m->is_dead_loop_safe()) { // Only look for unsafe cases. |
duke@435 | 1577 | if (!visited.test_set(m->_idx)) |
duke@435 | 1578 | nstack.push(m); |
duke@435 | 1579 | } |
duke@435 | 1580 | } |
duke@435 | 1581 | } |
duke@435 | 1582 | return false; // The phi is not reachable from its inputs |
duke@435 | 1583 | } |
duke@435 | 1584 | |
duke@435 | 1585 | |
duke@435 | 1586 | //------------------------------Ideal------------------------------------------ |
duke@435 | 1587 | // Return a node which is more "ideal" than the current node. Must preserve |
duke@435 | 1588 | // the CFG, but we can still strip out dead paths. |
duke@435 | 1589 | Node *PhiNode::Ideal(PhaseGVN *phase, bool can_reshape) { |
duke@435 | 1590 | // The next should never happen after 6297035 fix. |
duke@435 | 1591 | if( is_copy() ) // Already degraded to a Copy ? |
duke@435 | 1592 | return NULL; // No change |
duke@435 | 1593 | |
duke@435 | 1594 | Node *r = in(0); // RegionNode |
duke@435 | 1595 | assert(r->in(0) == NULL || !r->in(0)->is_Root(), "not a specially hidden merge"); |
duke@435 | 1596 | |
duke@435 | 1597 | // Note: During parsing, phis are often transformed before their regions. |
duke@435 | 1598 | // This means we have to use type_or_null to defend against untyped regions. |
duke@435 | 1599 | if( phase->type_or_null(r) == Type::TOP ) // Dead code? |
duke@435 | 1600 | return NULL; // No change |
duke@435 | 1601 | |
duke@435 | 1602 | Node *top = phase->C->top(); |
kvn@1448 | 1603 | bool new_phi = (outcnt() == 0); // transforming new Phi |
kvn@2930 | 1604 | // No change for igvn if new phi is not hooked |
kvn@2930 | 1605 | if (new_phi && can_reshape) |
kvn@2930 | 1606 | return NULL; |
duke@435 | 1607 | |
duke@435 | 1608 | // The are 2 situations when only one valid phi's input is left |
duke@435 | 1609 | // (in addition to Region input). |
duke@435 | 1610 | // One: region is not loop - replace phi with this input. |
duke@435 | 1611 | // Two: region is loop - replace phi with top since this data path is dead |
duke@435 | 1612 | // and we need to break the dead data loop. |
duke@435 | 1613 | Node* progress = NULL; // Record if any progress made |
duke@435 | 1614 | for( uint j = 1; j < req(); ++j ){ // For all paths in |
duke@435 | 1615 | // Check unreachable control paths |
duke@435 | 1616 | Node* rc = r->in(j); |
duke@435 | 1617 | Node* n = in(j); // Get the input |
duke@435 | 1618 | if (rc == NULL || phase->type(rc) == Type::TOP) { |
duke@435 | 1619 | if (n != top) { // Not already top? |
roland@4357 | 1620 | PhaseIterGVN *igvn = phase->is_IterGVN(); |
roland@4357 | 1621 | if (can_reshape && igvn != NULL) { |
roland@4357 | 1622 | igvn->_worklist.push(r); |
roland@4357 | 1623 | } |
duke@435 | 1624 | set_req(j, top); // Nuke it down |
duke@435 | 1625 | progress = this; // Record progress |
duke@435 | 1626 | } |
duke@435 | 1627 | } |
duke@435 | 1628 | } |
duke@435 | 1629 | |
kvn@1448 | 1630 | if (can_reshape && outcnt() == 0) { |
kvn@1448 | 1631 | // set_req() above may kill outputs if Phi is referenced |
kvn@1448 | 1632 | // only by itself on the dead (top) control path. |
kvn@1448 | 1633 | return top; |
kvn@1448 | 1634 | } |
kvn@1448 | 1635 | |
duke@435 | 1636 | Node* uin = unique_input(phase); |
duke@435 | 1637 | if (uin == top) { // Simplest case: no alive inputs. |
duke@435 | 1638 | if (can_reshape) // IGVN transformation |
duke@435 | 1639 | return top; |
duke@435 | 1640 | else |
duke@435 | 1641 | return NULL; // Identity will return TOP |
duke@435 | 1642 | } else if (uin != NULL) { |
duke@435 | 1643 | // Only one not-NULL unique input path is left. |
duke@435 | 1644 | // Determine if this input is backedge of a loop. |
duke@435 | 1645 | // (Skip new phis which have no uses and dead regions). |
kvn@3309 | 1646 | if (outcnt() > 0 && r->in(0) != NULL) { |
duke@435 | 1647 | // First, take the short cut when we know it is a loop and |
duke@435 | 1648 | // the EntryControl data path is dead. |
kvn@3309 | 1649 | // Loop node may have only one input because entry path |
kvn@3309 | 1650 | // is removed in PhaseIdealLoop::Dominators(). |
kvn@3309 | 1651 | assert(!r->is_Loop() || r->req() <= 3, "Loop node should have 3 or less inputs"); |
kvn@3309 | 1652 | bool is_loop = (r->is_Loop() && r->req() == 3); |
duke@435 | 1653 | // Then, check if there is a data loop when phi references itself directly |
duke@435 | 1654 | // or through other data nodes. |
kvn@3407 | 1655 | if (is_loop && !uin->eqv_uncast(in(LoopNode::EntryControl)) || |
kvn@3309 | 1656 | !is_loop && is_unsafe_data_reference(uin)) { |
duke@435 | 1657 | // Break this data loop to avoid creation of a dead loop. |
duke@435 | 1658 | if (can_reshape) { |
duke@435 | 1659 | return top; |
duke@435 | 1660 | } else { |
duke@435 | 1661 | // We can't return top if we are in Parse phase - cut inputs only |
duke@435 | 1662 | // let Identity to handle the case. |
duke@435 | 1663 | replace_edge(uin, top); |
duke@435 | 1664 | return NULL; |
duke@435 | 1665 | } |
duke@435 | 1666 | } |
duke@435 | 1667 | } |
duke@435 | 1668 | |
duke@435 | 1669 | // One unique input. |
duke@435 | 1670 | debug_only(Node* ident = Identity(phase)); |
duke@435 | 1671 | // The unique input must eventually be detected by the Identity call. |
duke@435 | 1672 | #ifdef ASSERT |
duke@435 | 1673 | if (ident != uin && !ident->is_top()) { |
duke@435 | 1674 | // print this output before failing assert |
duke@435 | 1675 | r->dump(3); |
duke@435 | 1676 | this->dump(3); |
duke@435 | 1677 | ident->dump(); |
duke@435 | 1678 | uin->dump(); |
duke@435 | 1679 | } |
duke@435 | 1680 | #endif |
duke@435 | 1681 | assert(ident == uin || ident->is_top(), "Identity must clean this up"); |
duke@435 | 1682 | return NULL; |
duke@435 | 1683 | } |
duke@435 | 1684 | |
duke@435 | 1685 | |
duke@435 | 1686 | Node* opt = NULL; |
duke@435 | 1687 | int true_path = is_diamond_phi(); |
duke@435 | 1688 | if( true_path != 0 ) { |
duke@435 | 1689 | // Check for CMove'ing identity. If it would be unsafe, |
duke@435 | 1690 | // handle it here. In the safe case, let Identity handle it. |
duke@435 | 1691 | Node* unsafe_id = is_cmove_id(phase, true_path); |
duke@435 | 1692 | if( unsafe_id != NULL && is_unsafe_data_reference(unsafe_id) ) |
duke@435 | 1693 | opt = unsafe_id; |
duke@435 | 1694 | |
duke@435 | 1695 | // Check for simple convert-to-boolean pattern |
duke@435 | 1696 | if( opt == NULL ) |
duke@435 | 1697 | opt = is_x2logic(phase, this, true_path); |
duke@435 | 1698 | |
duke@435 | 1699 | // Check for absolute value |
duke@435 | 1700 | if( opt == NULL ) |
duke@435 | 1701 | opt = is_absolute(phase, this, true_path); |
duke@435 | 1702 | |
duke@435 | 1703 | // Check for conditional add |
duke@435 | 1704 | if( opt == NULL && can_reshape ) |
duke@435 | 1705 | opt = is_cond_add(phase, this, true_path); |
duke@435 | 1706 | |
duke@435 | 1707 | // These 4 optimizations could subsume the phi: |
duke@435 | 1708 | // have to check for a dead data loop creation. |
duke@435 | 1709 | if( opt != NULL ) { |
duke@435 | 1710 | if( opt == unsafe_id || is_unsafe_data_reference(opt) ) { |
duke@435 | 1711 | // Found dead loop. |
duke@435 | 1712 | if( can_reshape ) |
duke@435 | 1713 | return top; |
duke@435 | 1714 | // We can't return top if we are in Parse phase - cut inputs only |
duke@435 | 1715 | // to stop further optimizations for this phi. Identity will return TOP. |
duke@435 | 1716 | assert(req() == 3, "only diamond merge phi here"); |
duke@435 | 1717 | set_req(1, top); |
duke@435 | 1718 | set_req(2, top); |
duke@435 | 1719 | return NULL; |
duke@435 | 1720 | } else { |
duke@435 | 1721 | return opt; |
duke@435 | 1722 | } |
duke@435 | 1723 | } |
duke@435 | 1724 | } |
duke@435 | 1725 | |
duke@435 | 1726 | // Check for merging identical values and split flow paths |
duke@435 | 1727 | if (can_reshape) { |
duke@435 | 1728 | opt = split_flow_path(phase, this); |
duke@435 | 1729 | // This optimization only modifies phi - don't need to check for dead loop. |
duke@435 | 1730 | assert(opt == NULL || phase->eqv(opt, this), "do not elide phi"); |
duke@435 | 1731 | if (opt != NULL) return opt; |
duke@435 | 1732 | } |
duke@435 | 1733 | |
kvn@1897 | 1734 | if (in(1) != NULL && in(1)->Opcode() == Op_AddP && can_reshape) { |
kvn@1897 | 1735 | // Try to undo Phi of AddP: |
kvn@1897 | 1736 | // (Phi (AddP base base y) (AddP base2 base2 y)) |
kvn@1897 | 1737 | // becomes: |
kvn@1897 | 1738 | // newbase := (Phi base base2) |
kvn@1897 | 1739 | // (AddP newbase newbase y) |
kvn@1897 | 1740 | // |
kvn@1897 | 1741 | // This occurs as a result of unsuccessful split_thru_phi and |
kvn@1897 | 1742 | // interferes with taking advantage of addressing modes. See the |
kvn@1897 | 1743 | // clone_shift_expressions code in matcher.cpp |
kvn@1897 | 1744 | Node* addp = in(1); |
kvn@1897 | 1745 | const Type* type = addp->in(AddPNode::Base)->bottom_type(); |
kvn@1897 | 1746 | Node* y = addp->in(AddPNode::Offset); |
kvn@1897 | 1747 | if (y != NULL && addp->in(AddPNode::Base) == addp->in(AddPNode::Address)) { |
kvn@1897 | 1748 | // make sure that all the inputs are similar to the first one, |
kvn@1897 | 1749 | // i.e. AddP with base == address and same offset as first AddP |
kvn@1897 | 1750 | bool doit = true; |
kvn@1897 | 1751 | for (uint i = 2; i < req(); i++) { |
kvn@1897 | 1752 | if (in(i) == NULL || |
kvn@1897 | 1753 | in(i)->Opcode() != Op_AddP || |
kvn@1897 | 1754 | in(i)->in(AddPNode::Base) != in(i)->in(AddPNode::Address) || |
kvn@1897 | 1755 | in(i)->in(AddPNode::Offset) != y) { |
kvn@1897 | 1756 | doit = false; |
kvn@1897 | 1757 | break; |
kvn@1897 | 1758 | } |
kvn@1897 | 1759 | // Accumulate type for resulting Phi |
kvn@1897 | 1760 | type = type->meet(in(i)->in(AddPNode::Base)->bottom_type()); |
kvn@1897 | 1761 | } |
kvn@1897 | 1762 | Node* base = NULL; |
kvn@1897 | 1763 | if (doit) { |
kvn@1897 | 1764 | // Check for neighboring AddP nodes in a tree. |
kvn@1897 | 1765 | // If they have a base, use that it. |
kvn@1897 | 1766 | for (DUIterator_Fast kmax, k = this->fast_outs(kmax); k < kmax; k++) { |
kvn@1897 | 1767 | Node* u = this->fast_out(k); |
kvn@1897 | 1768 | if (u->is_AddP()) { |
kvn@1897 | 1769 | Node* base2 = u->in(AddPNode::Base); |
kvn@1897 | 1770 | if (base2 != NULL && !base2->is_top()) { |
kvn@1897 | 1771 | if (base == NULL) |
kvn@1897 | 1772 | base = base2; |
kvn@1897 | 1773 | else if (base != base2) |
kvn@1897 | 1774 | { doit = false; break; } |
kvn@1897 | 1775 | } |
kvn@1897 | 1776 | } |
kvn@1897 | 1777 | } |
kvn@1897 | 1778 | } |
kvn@1897 | 1779 | if (doit) { |
kvn@1897 | 1780 | if (base == NULL) { |
kvn@4115 | 1781 | base = new (phase->C) PhiNode(in(0), type, NULL); |
kvn@1897 | 1782 | for (uint i = 1; i < req(); i++) { |
kvn@1897 | 1783 | base->init_req(i, in(i)->in(AddPNode::Base)); |
kvn@1897 | 1784 | } |
kvn@1897 | 1785 | phase->is_IterGVN()->register_new_node_with_optimizer(base); |
kvn@1897 | 1786 | } |
kvn@4115 | 1787 | return new (phase->C) AddPNode(base, base, y); |
kvn@1897 | 1788 | } |
kvn@1897 | 1789 | } |
kvn@1897 | 1790 | } |
kvn@1897 | 1791 | |
duke@435 | 1792 | // Split phis through memory merges, so that the memory merges will go away. |
duke@435 | 1793 | // Piggy-back this transformation on the search for a unique input.... |
duke@435 | 1794 | // It will be as if the merged memory is the unique value of the phi. |
duke@435 | 1795 | // (Do not attempt this optimization unless parsing is complete. |
duke@435 | 1796 | // It would make the parser's memory-merge logic sick.) |
duke@435 | 1797 | // (MergeMemNode is not dead_loop_safe - need to check for dead loop.) |
duke@435 | 1798 | if (progress == NULL && can_reshape && type() == Type::MEMORY) { |
duke@435 | 1799 | // see if this phi should be sliced |
duke@435 | 1800 | uint merge_width = 0; |
duke@435 | 1801 | bool saw_self = false; |
duke@435 | 1802 | for( uint i=1; i<req(); ++i ) {// For all paths in |
duke@435 | 1803 | Node *ii = in(i); |
duke@435 | 1804 | if (ii->is_MergeMem()) { |
duke@435 | 1805 | MergeMemNode* n = ii->as_MergeMem(); |
duke@435 | 1806 | merge_width = MAX2(merge_width, n->req()); |
duke@435 | 1807 | saw_self = saw_self || phase->eqv(n->base_memory(), this); |
duke@435 | 1808 | } |
duke@435 | 1809 | } |
duke@435 | 1810 | |
duke@435 | 1811 | // This restriction is temporarily necessary to ensure termination: |
duke@435 | 1812 | if (!saw_self && adr_type() == TypePtr::BOTTOM) merge_width = 0; |
duke@435 | 1813 | |
duke@435 | 1814 | if (merge_width > Compile::AliasIdxRaw) { |
duke@435 | 1815 | // found at least one non-empty MergeMem |
duke@435 | 1816 | const TypePtr* at = adr_type(); |
duke@435 | 1817 | if (at != TypePtr::BOTTOM) { |
duke@435 | 1818 | // Patch the existing phi to select an input from the merge: |
duke@435 | 1819 | // Phi:AT1(...MergeMem(m0, m1, m2)...) into |
duke@435 | 1820 | // Phi:AT1(...m1...) |
duke@435 | 1821 | int alias_idx = phase->C->get_alias_index(at); |
duke@435 | 1822 | for (uint i=1; i<req(); ++i) { |
duke@435 | 1823 | Node *ii = in(i); |
duke@435 | 1824 | if (ii->is_MergeMem()) { |
duke@435 | 1825 | MergeMemNode* n = ii->as_MergeMem(); |
duke@435 | 1826 | // compress paths and change unreachable cycles to TOP |
duke@435 | 1827 | // If not, we can update the input infinitely along a MergeMem cycle |
duke@435 | 1828 | // Equivalent code is in MemNode::Ideal_common |
never@802 | 1829 | Node *m = phase->transform(n); |
never@802 | 1830 | if (outcnt() == 0) { // Above transform() may kill us! |
kvn@1448 | 1831 | return top; |
never@802 | 1832 | } |
twisti@1040 | 1833 | // If transformed to a MergeMem, get the desired slice |
duke@435 | 1834 | // Otherwise the returned node represents memory for every slice |
duke@435 | 1835 | Node *new_mem = (m->is_MergeMem()) ? |
duke@435 | 1836 | m->as_MergeMem()->memory_at(alias_idx) : m; |
duke@435 | 1837 | // Update input if it is progress over what we have now |
duke@435 | 1838 | if (new_mem != ii) { |
duke@435 | 1839 | set_req(i, new_mem); |
duke@435 | 1840 | progress = this; |
duke@435 | 1841 | } |
duke@435 | 1842 | } |
duke@435 | 1843 | } |
duke@435 | 1844 | } else { |
duke@435 | 1845 | // We know that at least one MergeMem->base_memory() == this |
duke@435 | 1846 | // (saw_self == true). If all other inputs also references this phi |
duke@435 | 1847 | // (directly or through data nodes) - it is dead loop. |
duke@435 | 1848 | bool saw_safe_input = false; |
duke@435 | 1849 | for (uint j = 1; j < req(); ++j) { |
duke@435 | 1850 | Node *n = in(j); |
duke@435 | 1851 | if (n->is_MergeMem() && n->as_MergeMem()->base_memory() == this) |
duke@435 | 1852 | continue; // skip known cases |
duke@435 | 1853 | if (!is_unsafe_data_reference(n)) { |
duke@435 | 1854 | saw_safe_input = true; // found safe input |
duke@435 | 1855 | break; |
duke@435 | 1856 | } |
duke@435 | 1857 | } |
duke@435 | 1858 | if (!saw_safe_input) |
duke@435 | 1859 | return top; // all inputs reference back to this phi - dead loop |
duke@435 | 1860 | |
duke@435 | 1861 | // Phi(...MergeMem(m0, m1:AT1, m2:AT2)...) into |
duke@435 | 1862 | // MergeMem(Phi(...m0...), Phi:AT1(...m1...), Phi:AT2(...m2...)) |
duke@435 | 1863 | PhaseIterGVN *igvn = phase->is_IterGVN(); |
kvn@4115 | 1864 | Node* hook = new (phase->C) Node(1); |
duke@435 | 1865 | PhiNode* new_base = (PhiNode*) clone(); |
duke@435 | 1866 | // Must eagerly register phis, since they participate in loops. |
duke@435 | 1867 | if (igvn) { |
duke@435 | 1868 | igvn->register_new_node_with_optimizer(new_base); |
duke@435 | 1869 | hook->add_req(new_base); |
duke@435 | 1870 | } |
duke@435 | 1871 | MergeMemNode* result = MergeMemNode::make(phase->C, new_base); |
duke@435 | 1872 | for (uint i = 1; i < req(); ++i) { |
duke@435 | 1873 | Node *ii = in(i); |
duke@435 | 1874 | if (ii->is_MergeMem()) { |
duke@435 | 1875 | MergeMemNode* n = ii->as_MergeMem(); |
duke@435 | 1876 | for (MergeMemStream mms(result, n); mms.next_non_empty2(); ) { |
duke@435 | 1877 | // If we have not seen this slice yet, make a phi for it. |
duke@435 | 1878 | bool made_new_phi = false; |
duke@435 | 1879 | if (mms.is_empty()) { |
duke@435 | 1880 | Node* new_phi = new_base->slice_memory(mms.adr_type(phase->C)); |
duke@435 | 1881 | made_new_phi = true; |
duke@435 | 1882 | if (igvn) { |
duke@435 | 1883 | igvn->register_new_node_with_optimizer(new_phi); |
duke@435 | 1884 | hook->add_req(new_phi); |
duke@435 | 1885 | } |
duke@435 | 1886 | mms.set_memory(new_phi); |
duke@435 | 1887 | } |
duke@435 | 1888 | Node* phi = mms.memory(); |
duke@435 | 1889 | assert(made_new_phi || phi->in(i) == n, "replace the i-th merge by a slice"); |
duke@435 | 1890 | phi->set_req(i, mms.memory2()); |
duke@435 | 1891 | } |
duke@435 | 1892 | } |
duke@435 | 1893 | } |
duke@435 | 1894 | // Distribute all self-loops. |
duke@435 | 1895 | { // (Extra braces to hide mms.) |
duke@435 | 1896 | for (MergeMemStream mms(result); mms.next_non_empty(); ) { |
duke@435 | 1897 | Node* phi = mms.memory(); |
duke@435 | 1898 | for (uint i = 1; i < req(); ++i) { |
duke@435 | 1899 | if (phi->in(i) == this) phi->set_req(i, phi); |
duke@435 | 1900 | } |
duke@435 | 1901 | } |
duke@435 | 1902 | } |
duke@435 | 1903 | // now transform the new nodes, and return the mergemem |
duke@435 | 1904 | for (MergeMemStream mms(result); mms.next_non_empty(); ) { |
duke@435 | 1905 | Node* phi = mms.memory(); |
duke@435 | 1906 | mms.set_memory(phase->transform(phi)); |
duke@435 | 1907 | } |
duke@435 | 1908 | if (igvn) { // Unhook. |
duke@435 | 1909 | igvn->hash_delete(hook); |
duke@435 | 1910 | for (uint i = 1; i < hook->req(); i++) { |
duke@435 | 1911 | hook->set_req(i, NULL); |
duke@435 | 1912 | } |
duke@435 | 1913 | } |
duke@435 | 1914 | // Replace self with the result. |
duke@435 | 1915 | return result; |
duke@435 | 1916 | } |
duke@435 | 1917 | } |
kvn@509 | 1918 | // |
kvn@509 | 1919 | // Other optimizations on the memory chain |
kvn@509 | 1920 | // |
kvn@509 | 1921 | const TypePtr* at = adr_type(); |
kvn@509 | 1922 | for( uint i=1; i<req(); ++i ) {// For all paths in |
kvn@509 | 1923 | Node *ii = in(i); |
kvn@5110 | 1924 | Node *new_in = MemNode::optimize_memory_chain(ii, at, NULL, phase); |
kvn@509 | 1925 | if (ii != new_in ) { |
kvn@509 | 1926 | set_req(i, new_in); |
kvn@509 | 1927 | progress = this; |
kvn@509 | 1928 | } |
kvn@509 | 1929 | } |
duke@435 | 1930 | } |
duke@435 | 1931 | |
kvn@803 | 1932 | #ifdef _LP64 |
roland@4159 | 1933 | // Push DecodeN/DecodeNKlass down through phi. |
kvn@803 | 1934 | // The rest of phi graph will transform by split EncodeP node though phis up. |
roland@4159 | 1935 | if ((UseCompressedOops || UseCompressedKlassPointers) && can_reshape && progress == NULL) { |
kvn@803 | 1936 | bool may_push = true; |
kvn@803 | 1937 | bool has_decodeN = false; |
roland@4159 | 1938 | bool is_decodeN = false; |
kvn@803 | 1939 | for (uint i=1; i<req(); ++i) {// For all paths in |
kvn@803 | 1940 | Node *ii = in(i); |
roland@4159 | 1941 | if (ii->is_DecodeNarrowPtr() && ii->bottom_type() == bottom_type()) { |
kvn@1334 | 1942 | // Do optimization if a non dead path exist. |
kvn@1288 | 1943 | if (ii->in(1)->bottom_type() != Type::TOP) { |
kvn@1288 | 1944 | has_decodeN = true; |
roland@4159 | 1945 | is_decodeN = ii->is_DecodeN(); |
kvn@1288 | 1946 | } |
kvn@803 | 1947 | } else if (!ii->is_Phi()) { |
kvn@803 | 1948 | may_push = false; |
kvn@803 | 1949 | } |
kvn@803 | 1950 | } |
kvn@803 | 1951 | |
kvn@803 | 1952 | if (has_decodeN && may_push) { |
kvn@803 | 1953 | PhaseIterGVN *igvn = phase->is_IterGVN(); |
kvn@1334 | 1954 | // Make narrow type for new phi. |
roland@4159 | 1955 | const Type* narrow_t; |
roland@4159 | 1956 | if (is_decodeN) { |
roland@4159 | 1957 | narrow_t = TypeNarrowOop::make(this->bottom_type()->is_ptr()); |
roland@4159 | 1958 | } else { |
roland@4159 | 1959 | narrow_t = TypeNarrowKlass::make(this->bottom_type()->is_ptr()); |
roland@4159 | 1960 | } |
kvn@4115 | 1961 | PhiNode* new_phi = new (phase->C) PhiNode(r, narrow_t); |
kvn@803 | 1962 | uint orig_cnt = req(); |
kvn@803 | 1963 | for (uint i=1; i<req(); ++i) {// For all paths in |
kvn@803 | 1964 | Node *ii = in(i); |
kvn@803 | 1965 | Node* new_ii = NULL; |
roland@4159 | 1966 | if (ii->is_DecodeNarrowPtr()) { |
kvn@803 | 1967 | assert(ii->bottom_type() == bottom_type(), "sanity"); |
kvn@803 | 1968 | new_ii = ii->in(1); |
kvn@803 | 1969 | } else { |
kvn@803 | 1970 | assert(ii->is_Phi(), "sanity"); |
kvn@803 | 1971 | if (ii->as_Phi() == this) { |
kvn@803 | 1972 | new_ii = new_phi; |
kvn@803 | 1973 | } else { |
roland@4159 | 1974 | if (is_decodeN) { |
roland@4159 | 1975 | new_ii = new (phase->C) EncodePNode(ii, narrow_t); |
roland@4159 | 1976 | } else { |
roland@4159 | 1977 | new_ii = new (phase->C) EncodePKlassNode(ii, narrow_t); |
roland@4159 | 1978 | } |
kvn@803 | 1979 | igvn->register_new_node_with_optimizer(new_ii); |
kvn@803 | 1980 | } |
kvn@803 | 1981 | } |
kvn@803 | 1982 | new_phi->set_req(i, new_ii); |
kvn@803 | 1983 | } |
kvn@803 | 1984 | igvn->register_new_node_with_optimizer(new_phi, this); |
roland@4159 | 1985 | if (is_decodeN) { |
roland@4159 | 1986 | progress = new (phase->C) DecodeNNode(new_phi, bottom_type()); |
roland@4159 | 1987 | } else { |
roland@4159 | 1988 | progress = new (phase->C) DecodeNKlassNode(new_phi, bottom_type()); |
roland@4159 | 1989 | } |
kvn@803 | 1990 | } |
kvn@803 | 1991 | } |
kvn@803 | 1992 | #endif |
kvn@803 | 1993 | |
duke@435 | 1994 | return progress; // Return any progress |
duke@435 | 1995 | } |
duke@435 | 1996 | |
kvn@835 | 1997 | //------------------------------is_tripcount----------------------------------- |
kvn@835 | 1998 | bool PhiNode::is_tripcount() const { |
kvn@835 | 1999 | return (in(0) != NULL && in(0)->is_CountedLoop() && |
kvn@835 | 2000 | in(0)->as_CountedLoop()->phi() == this); |
kvn@835 | 2001 | } |
kvn@835 | 2002 | |
duke@435 | 2003 | //------------------------------out_RegMask------------------------------------ |
duke@435 | 2004 | const RegMask &PhiNode::in_RegMask(uint i) const { |
duke@435 | 2005 | return i ? out_RegMask() : RegMask::Empty; |
duke@435 | 2006 | } |
duke@435 | 2007 | |
duke@435 | 2008 | const RegMask &PhiNode::out_RegMask() const { |
coleenp@4037 | 2009 | uint ideal_reg = _type->ideal_reg(); |
duke@435 | 2010 | assert( ideal_reg != Node::NotAMachineReg, "invalid type at Phi" ); |
duke@435 | 2011 | if( ideal_reg == 0 ) return RegMask::Empty; |
duke@435 | 2012 | return *(Compile::current()->matcher()->idealreg2spillmask[ideal_reg]); |
duke@435 | 2013 | } |
duke@435 | 2014 | |
duke@435 | 2015 | #ifndef PRODUCT |
duke@435 | 2016 | void PhiNode::dump_spec(outputStream *st) const { |
duke@435 | 2017 | TypeNode::dump_spec(st); |
kvn@835 | 2018 | if (is_tripcount()) { |
duke@435 | 2019 | st->print(" #tripcount"); |
duke@435 | 2020 | } |
duke@435 | 2021 | } |
duke@435 | 2022 | #endif |
duke@435 | 2023 | |
duke@435 | 2024 | |
duke@435 | 2025 | //============================================================================= |
duke@435 | 2026 | const Type *GotoNode::Value( PhaseTransform *phase ) const { |
duke@435 | 2027 | // If the input is reachable, then we are executed. |
duke@435 | 2028 | // If the input is not reachable, then we are not executed. |
duke@435 | 2029 | return phase->type(in(0)); |
duke@435 | 2030 | } |
duke@435 | 2031 | |
duke@435 | 2032 | Node *GotoNode::Identity( PhaseTransform *phase ) { |
duke@435 | 2033 | return in(0); // Simple copy of incoming control |
duke@435 | 2034 | } |
duke@435 | 2035 | |
duke@435 | 2036 | const RegMask &GotoNode::out_RegMask() const { |
duke@435 | 2037 | return RegMask::Empty; |
duke@435 | 2038 | } |
duke@435 | 2039 | |
duke@435 | 2040 | //============================================================================= |
duke@435 | 2041 | const RegMask &JumpNode::out_RegMask() const { |
duke@435 | 2042 | return RegMask::Empty; |
duke@435 | 2043 | } |
duke@435 | 2044 | |
duke@435 | 2045 | //============================================================================= |
duke@435 | 2046 | const RegMask &JProjNode::out_RegMask() const { |
duke@435 | 2047 | return RegMask::Empty; |
duke@435 | 2048 | } |
duke@435 | 2049 | |
duke@435 | 2050 | //============================================================================= |
duke@435 | 2051 | const RegMask &CProjNode::out_RegMask() const { |
duke@435 | 2052 | return RegMask::Empty; |
duke@435 | 2053 | } |
duke@435 | 2054 | |
duke@435 | 2055 | |
duke@435 | 2056 | |
duke@435 | 2057 | //============================================================================= |
duke@435 | 2058 | |
duke@435 | 2059 | uint PCTableNode::hash() const { return Node::hash() + _size; } |
duke@435 | 2060 | uint PCTableNode::cmp( const Node &n ) const |
duke@435 | 2061 | { return _size == ((PCTableNode&)n)._size; } |
duke@435 | 2062 | |
duke@435 | 2063 | const Type *PCTableNode::bottom_type() const { |
duke@435 | 2064 | const Type** f = TypeTuple::fields(_size); |
duke@435 | 2065 | for( uint i = 0; i < _size; i++ ) f[i] = Type::CONTROL; |
duke@435 | 2066 | return TypeTuple::make(_size, f); |
duke@435 | 2067 | } |
duke@435 | 2068 | |
duke@435 | 2069 | //------------------------------Value------------------------------------------ |
duke@435 | 2070 | // Compute the type of the PCTableNode. If reachable it is a tuple of |
duke@435 | 2071 | // Control, otherwise the table targets are not reachable |
duke@435 | 2072 | const Type *PCTableNode::Value( PhaseTransform *phase ) const { |
duke@435 | 2073 | if( phase->type(in(0)) == Type::CONTROL ) |
duke@435 | 2074 | return bottom_type(); |
duke@435 | 2075 | return Type::TOP; // All paths dead? Then so are we |
duke@435 | 2076 | } |
duke@435 | 2077 | |
duke@435 | 2078 | //------------------------------Ideal------------------------------------------ |
duke@435 | 2079 | // Return a node which is more "ideal" than the current node. Strip out |
duke@435 | 2080 | // control copies |
duke@435 | 2081 | Node *PCTableNode::Ideal(PhaseGVN *phase, bool can_reshape) { |
duke@435 | 2082 | return remove_dead_region(phase, can_reshape) ? this : NULL; |
duke@435 | 2083 | } |
duke@435 | 2084 | |
duke@435 | 2085 | //============================================================================= |
duke@435 | 2086 | uint JumpProjNode::hash() const { |
duke@435 | 2087 | return Node::hash() + _dest_bci; |
duke@435 | 2088 | } |
duke@435 | 2089 | |
duke@435 | 2090 | uint JumpProjNode::cmp( const Node &n ) const { |
duke@435 | 2091 | return ProjNode::cmp(n) && |
duke@435 | 2092 | _dest_bci == ((JumpProjNode&)n)._dest_bci; |
duke@435 | 2093 | } |
duke@435 | 2094 | |
duke@435 | 2095 | #ifndef PRODUCT |
duke@435 | 2096 | void JumpProjNode::dump_spec(outputStream *st) const { |
duke@435 | 2097 | ProjNode::dump_spec(st); |
duke@435 | 2098 | st->print("@bci %d ",_dest_bci); |
duke@435 | 2099 | } |
duke@435 | 2100 | #endif |
duke@435 | 2101 | |
duke@435 | 2102 | //============================================================================= |
duke@435 | 2103 | //------------------------------Value------------------------------------------ |
duke@435 | 2104 | // Check for being unreachable, or for coming from a Rethrow. Rethrow's cannot |
duke@435 | 2105 | // have the default "fall_through_index" path. |
duke@435 | 2106 | const Type *CatchNode::Value( PhaseTransform *phase ) const { |
duke@435 | 2107 | // Unreachable? Then so are all paths from here. |
duke@435 | 2108 | if( phase->type(in(0)) == Type::TOP ) return Type::TOP; |
duke@435 | 2109 | // First assume all paths are reachable |
duke@435 | 2110 | const Type** f = TypeTuple::fields(_size); |
duke@435 | 2111 | for( uint i = 0; i < _size; i++ ) f[i] = Type::CONTROL; |
duke@435 | 2112 | // Identify cases that will always throw an exception |
duke@435 | 2113 | // () rethrow call |
duke@435 | 2114 | // () virtual or interface call with NULL receiver |
duke@435 | 2115 | // () call is a check cast with incompatible arguments |
duke@435 | 2116 | if( in(1)->is_Proj() ) { |
duke@435 | 2117 | Node *i10 = in(1)->in(0); |
duke@435 | 2118 | if( i10->is_Call() ) { |
duke@435 | 2119 | CallNode *call = i10->as_Call(); |
duke@435 | 2120 | // Rethrows always throw exceptions, never return |
duke@435 | 2121 | if (call->entry_point() == OptoRuntime::rethrow_stub()) { |
duke@435 | 2122 | f[CatchProjNode::fall_through_index] = Type::TOP; |
duke@435 | 2123 | } else if( call->req() > TypeFunc::Parms ) { |
duke@435 | 2124 | const Type *arg0 = phase->type( call->in(TypeFunc::Parms) ); |
twisti@1040 | 2125 | // Check for null receiver to virtual or interface calls |
duke@435 | 2126 | if( call->is_CallDynamicJava() && |
duke@435 | 2127 | arg0->higher_equal(TypePtr::NULL_PTR) ) { |
duke@435 | 2128 | f[CatchProjNode::fall_through_index] = Type::TOP; |
duke@435 | 2129 | } |
duke@435 | 2130 | } // End of if not a runtime stub |
duke@435 | 2131 | } // End of if have call above me |
duke@435 | 2132 | } // End of slot 1 is not a projection |
duke@435 | 2133 | return TypeTuple::make(_size, f); |
duke@435 | 2134 | } |
duke@435 | 2135 | |
duke@435 | 2136 | //============================================================================= |
duke@435 | 2137 | uint CatchProjNode::hash() const { |
duke@435 | 2138 | return Node::hash() + _handler_bci; |
duke@435 | 2139 | } |
duke@435 | 2140 | |
duke@435 | 2141 | |
duke@435 | 2142 | uint CatchProjNode::cmp( const Node &n ) const { |
duke@435 | 2143 | return ProjNode::cmp(n) && |
duke@435 | 2144 | _handler_bci == ((CatchProjNode&)n)._handler_bci; |
duke@435 | 2145 | } |
duke@435 | 2146 | |
duke@435 | 2147 | |
duke@435 | 2148 | //------------------------------Identity--------------------------------------- |
duke@435 | 2149 | // If only 1 target is possible, choose it if it is the main control |
duke@435 | 2150 | Node *CatchProjNode::Identity( PhaseTransform *phase ) { |
duke@435 | 2151 | // If my value is control and no other value is, then treat as ID |
duke@435 | 2152 | const TypeTuple *t = phase->type(in(0))->is_tuple(); |
duke@435 | 2153 | if (t->field_at(_con) != Type::CONTROL) return this; |
duke@435 | 2154 | // If we remove the last CatchProj and elide the Catch/CatchProj, then we |
duke@435 | 2155 | // also remove any exception table entry. Thus we must know the call |
duke@435 | 2156 | // feeding the Catch will not really throw an exception. This is ok for |
duke@435 | 2157 | // the main fall-thru control (happens when we know a call can never throw |
twisti@1040 | 2158 | // an exception) or for "rethrow", because a further optimization will |
duke@435 | 2159 | // yank the rethrow (happens when we inline a function that can throw an |
duke@435 | 2160 | // exception and the caller has no handler). Not legal, e.g., for passing |
duke@435 | 2161 | // a NULL receiver to a v-call, or passing bad types to a slow-check-cast. |
duke@435 | 2162 | // These cases MUST throw an exception via the runtime system, so the VM |
duke@435 | 2163 | // will be looking for a table entry. |
duke@435 | 2164 | Node *proj = in(0)->in(1); // Expect a proj feeding CatchNode |
duke@435 | 2165 | CallNode *call; |
duke@435 | 2166 | if (_con != TypeFunc::Control && // Bail out if not the main control. |
duke@435 | 2167 | !(proj->is_Proj() && // AND NOT a rethrow |
duke@435 | 2168 | proj->in(0)->is_Call() && |
duke@435 | 2169 | (call = proj->in(0)->as_Call()) && |
duke@435 | 2170 | call->entry_point() == OptoRuntime::rethrow_stub())) |
duke@435 | 2171 | return this; |
duke@435 | 2172 | |
duke@435 | 2173 | // Search for any other path being control |
duke@435 | 2174 | for (uint i = 0; i < t->cnt(); i++) { |
duke@435 | 2175 | if (i != _con && t->field_at(i) == Type::CONTROL) |
duke@435 | 2176 | return this; |
duke@435 | 2177 | } |
duke@435 | 2178 | // Only my path is possible; I am identity on control to the jump |
duke@435 | 2179 | return in(0)->in(0); |
duke@435 | 2180 | } |
duke@435 | 2181 | |
duke@435 | 2182 | |
duke@435 | 2183 | #ifndef PRODUCT |
duke@435 | 2184 | void CatchProjNode::dump_spec(outputStream *st) const { |
duke@435 | 2185 | ProjNode::dump_spec(st); |
duke@435 | 2186 | st->print("@bci %d ",_handler_bci); |
duke@435 | 2187 | } |
duke@435 | 2188 | #endif |
duke@435 | 2189 | |
duke@435 | 2190 | //============================================================================= |
duke@435 | 2191 | //------------------------------Identity--------------------------------------- |
duke@435 | 2192 | // Check for CreateEx being Identity. |
duke@435 | 2193 | Node *CreateExNode::Identity( PhaseTransform *phase ) { |
duke@435 | 2194 | if( phase->type(in(1)) == Type::TOP ) return in(1); |
duke@435 | 2195 | if( phase->type(in(0)) == Type::TOP ) return in(0); |
duke@435 | 2196 | // We only come from CatchProj, unless the CatchProj goes away. |
duke@435 | 2197 | // If the CatchProj is optimized away, then we just carry the |
duke@435 | 2198 | // exception oop through. |
duke@435 | 2199 | CallNode *call = in(1)->in(0)->as_Call(); |
duke@435 | 2200 | |
duke@435 | 2201 | return ( in(0)->is_CatchProj() && in(0)->in(0)->in(1) == in(1) ) |
duke@435 | 2202 | ? this |
duke@435 | 2203 | : call->in(TypeFunc::Parms); |
duke@435 | 2204 | } |
duke@435 | 2205 | |
duke@435 | 2206 | //============================================================================= |
never@562 | 2207 | //------------------------------Value------------------------------------------ |
never@562 | 2208 | // Check for being unreachable. |
never@562 | 2209 | const Type *NeverBranchNode::Value( PhaseTransform *phase ) const { |
never@562 | 2210 | if (!in(0) || in(0)->is_top()) return Type::TOP; |
never@562 | 2211 | return bottom_type(); |
never@562 | 2212 | } |
never@562 | 2213 | |
never@562 | 2214 | //------------------------------Ideal------------------------------------------ |
never@562 | 2215 | // Check for no longer being part of a loop |
never@562 | 2216 | Node *NeverBranchNode::Ideal(PhaseGVN *phase, bool can_reshape) { |
never@562 | 2217 | if (can_reshape && !in(0)->is_Loop()) { |
never@562 | 2218 | // Dead code elimination can sometimes delete this projection so |
never@562 | 2219 | // if it's not there, there's nothing to do. |
never@562 | 2220 | Node* fallthru = proj_out(0); |
never@562 | 2221 | if (fallthru != NULL) { |
kvn@1976 | 2222 | phase->is_IterGVN()->replace_node(fallthru, in(0)); |
never@562 | 2223 | } |
never@562 | 2224 | return phase->C->top(); |
never@562 | 2225 | } |
never@562 | 2226 | return NULL; |
never@562 | 2227 | } |
never@562 | 2228 | |
duke@435 | 2229 | #ifndef PRODUCT |
duke@435 | 2230 | void NeverBranchNode::format( PhaseRegAlloc *ra_, outputStream *st) const { |
duke@435 | 2231 | st->print("%s", Name()); |
duke@435 | 2232 | } |
duke@435 | 2233 | #endif |