1 // Copyright 2013 the V8 project authors. All rights reserved. 2 // Redistribution and use in source and binary forms, with or without 3 // modification, are permitted provided that the following conditions are 4 // met: 5 // 6 // * Redistributions of source code must retain the above copyright 7 // notice, this list of conditions and the following disclaimer. 8 // * Redistributions in binary form must reproduce the above 9 // copyright notice, this list of conditions and the following 10 // disclaimer in the documentation and/or other materials provided 11 // with the distribution. 12 // * Neither the name of Google Inc. nor the names of its 13 // contributors may be used to endorse or promote products derived 14 // from this software without specific prior written permission. 15 // 16 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 17 // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 18 // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 19 // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 20 // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 21 // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 22 // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 23 // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 24 // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 25 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 26 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 27 28 #include "hydrogen.h" 29 #include "hydrogen-osr.h" 30 31 namespace v8 { 32 namespace internal { 33 34 // True iff. we are compiling for OSR and the statement is the entry. 35 bool HOsrBuilder::HasOsrEntryAt(IterationStatement* statement) { 36 return statement->OsrEntryId() == builder_->current_info()->osr_ast_id(); 37 } 38 39 40 // Build a new loop header block and set it as the current block. 41 HBasicBlock *HOsrBuilder::BuildLoopEntry() { 42 HBasicBlock* loop_entry = builder_->CreateLoopHeaderBlock(); 43 builder_->current_block()->Goto(loop_entry); 44 builder_->set_current_block(loop_entry); 45 return loop_entry; 46 } 47 48 49 HBasicBlock* HOsrBuilder::BuildPossibleOsrLoopEntry( 50 IterationStatement* statement) { 51 // Check if there is an OSR here first. 52 if (!HasOsrEntryAt(statement)) return BuildLoopEntry(); 53 54 Zone* zone = builder_->zone(); 55 HGraph* graph = builder_->graph(); 56 57 // only one OSR point per compile is allowed. 58 ASSERT(graph->osr() == NULL); 59 60 // remember this builder as the one OSR builder in the graph. 61 graph->set_osr(this); 62 63 HBasicBlock* non_osr_entry = graph->CreateBasicBlock(); 64 osr_entry_ = graph->CreateBasicBlock(); 65 HValue* true_value = graph->GetConstantTrue(); 66 HBranch* test = new(zone) HBranch(true_value, ToBooleanStub::Types(), 67 non_osr_entry, osr_entry_); 68 builder_->current_block()->Finish(test); 69 70 HBasicBlock* loop_predecessor = graph->CreateBasicBlock(); 71 non_osr_entry->Goto(loop_predecessor); 72 73 builder_->set_current_block(osr_entry_); 74 osr_entry_->set_osr_entry(); 75 BailoutId osr_entry_id = statement->OsrEntryId(); 76 77 HEnvironment *environment = builder_->environment(); 78 int first_expression_index = environment->first_expression_index(); 79 int length = environment->length(); 80 osr_values_ = new(zone) ZoneList<HUnknownOSRValue*>(length, zone); 81 82 for (int i = 0; i < first_expression_index; ++i) { 83 HUnknownOSRValue* osr_value = builder_->Add<HUnknownOSRValue>(); 84 environment->Bind(i, osr_value); 85 osr_values_->Add(osr_value, zone); 86 } 87 88 if (first_expression_index != length) { 89 environment->Drop(length - first_expression_index); 90 for (int i = first_expression_index; i < length; ++i) { 91 HUnknownOSRValue* osr_value = builder_->Add<HUnknownOSRValue>(); 92 environment->Push(osr_value); 93 osr_values_->Add(osr_value, zone); 94 } 95 } 96 97 builder_->Add<HSimulate>(osr_entry_id); 98 builder_->Add<HOsrEntry>(osr_entry_id); 99 HContext* context = builder_->Add<HContext>(); 100 environment->BindContext(context); 101 builder_->current_block()->Goto(loop_predecessor); 102 loop_predecessor->SetJoinId(statement->EntryId()); 103 builder_->set_current_block(loop_predecessor); 104 105 // Create the final loop entry 106 osr_loop_entry_ = BuildLoopEntry(); 107 return osr_loop_entry_; 108 } 109 110 111 void HOsrBuilder::FinishGraph() { 112 // do nothing for now. 113 } 114 115 116 void HOsrBuilder::FinishOsrValues() { 117 const ZoneList<HPhi*>* phis = osr_loop_entry_->phis(); 118 for (int j = 0; j < phis->length(); j++) { 119 HPhi* phi = phis->at(j); 120 ASSERT(phi->HasMergedIndex()); 121 osr_values_->at(phi->merged_index())->set_incoming_value(phi); 122 } 123 } 124 125 } } // namespace v8::internal 126
