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 HBasicBlock* HOsrBuilder::BuildOsrLoopEntry(IterationStatement* statement) { 41 ASSERT(HasOsrEntryAt(statement)); 42 43 Zone* zone = builder_->zone(); 44 HGraph* graph = builder_->graph(); 45 46 // only one OSR point per compile is allowed. 47 ASSERT(graph->osr() == NULL); 48 49 // remember this builder as the one OSR builder in the graph. 50 graph->set_osr(this); 51 52 HBasicBlock* non_osr_entry = graph->CreateBasicBlock(); 53 osr_entry_ = graph->CreateBasicBlock(); 54 HValue* true_value = graph->GetConstantTrue(); 55 HBranch* test = builder_->New<HBranch>(true_value, ToBooleanStub::Types(), 56 non_osr_entry, osr_entry_); 57 builder_->FinishCurrentBlock(test); 58 59 HBasicBlock* loop_predecessor = graph->CreateBasicBlock(); 60 builder_->Goto(non_osr_entry, loop_predecessor); 61 62 builder_->set_current_block(osr_entry_); 63 osr_entry_->set_osr_entry(); 64 BailoutId osr_entry_id = statement->OsrEntryId(); 65 66 HEnvironment *environment = builder_->environment(); 67 int first_expression_index = environment->first_expression_index(); 68 int length = environment->length(); 69 osr_values_ = new(zone) ZoneList<HUnknownOSRValue*>(length, zone); 70 71 for (int i = 0; i < first_expression_index; ++i) { 72 HUnknownOSRValue* osr_value 73 = builder_->Add<HUnknownOSRValue>(environment, i); 74 environment->Bind(i, osr_value); 75 osr_values_->Add(osr_value, zone); 76 } 77 78 if (first_expression_index != length) { 79 environment->Drop(length - first_expression_index); 80 for (int i = first_expression_index; i < length; ++i) { 81 HUnknownOSRValue* osr_value 82 = builder_->Add<HUnknownOSRValue>(environment, i); 83 environment->Push(osr_value); 84 osr_values_->Add(osr_value, zone); 85 } 86 } 87 88 unoptimized_frame_slots_ = 89 environment->local_count() + environment->push_count(); 90 91 // Keep a copy of the old environment, since the OSR values need it 92 // to figure out where exactly they are located in the unoptimized frame. 93 environment = environment->Copy(); 94 builder_->current_block()->UpdateEnvironment(environment); 95 96 builder_->Add<HSimulate>(osr_entry_id); 97 builder_->Add<HOsrEntry>(osr_entry_id); 98 HContext* context = builder_->Add<HContext>(); 99 environment->BindContext(context); 100 builder_->Goto(loop_predecessor); 101 loop_predecessor->SetJoinId(statement->EntryId()); 102 builder_->set_current_block(loop_predecessor); 103 104 // Create the final loop entry 105 osr_loop_entry_ = builder_->BuildLoopEntry(); 106 return osr_loop_entry_; 107 } 108 109 110 void HOsrBuilder::FinishGraph() { 111 // do nothing for now. 112 } 113 114 115 void HOsrBuilder::FinishOsrValues() { 116 const ZoneList<HPhi*>* phis = osr_loop_entry_->phis(); 117 for (int j = 0; j < phis->length(); j++) { 118 HPhi* phi = phis->at(j); 119 if (phi->HasMergedIndex()) { 120 osr_values_->at(phi->merged_index())->set_incoming_value(phi); 121 } 122 } 123 } 124 125 } } // namespace v8::internal 126
