Emily Bernier | d0a1eb7 | 2015-03-24 16:35:39 -0400 | [diff] [blame^] | 1 | // Copyright 2013 the V8 project authors. All rights reserved. |
| 2 | // Use of this source code is governed by a BSD-style license that can be |
| 3 | // found in the LICENSE file. |
| 4 | |
| 5 | #ifndef V8_COMPILER_DIAMOND_H_ |
| 6 | #define V8_COMPILER_DIAMOND_H_ |
| 7 | |
| 8 | #include "src/v8.h" |
| 9 | |
| 10 | #include "src/compiler/common-operator.h" |
| 11 | #include "src/compiler/graph-inl.h" |
| 12 | #include "src/compiler/node.h" |
| 13 | |
| 14 | namespace v8 { |
| 15 | namespace internal { |
| 16 | namespace compiler { |
| 17 | |
| 18 | // A helper to make it easier to build diamond-shaped control patterns. |
| 19 | struct Diamond { |
| 20 | Graph* graph; |
| 21 | CommonOperatorBuilder* common; |
| 22 | Node* branch; |
| 23 | Node* if_true; |
| 24 | Node* if_false; |
| 25 | Node* merge; |
| 26 | |
| 27 | Diamond(Graph* g, CommonOperatorBuilder* b, Node* cond, |
| 28 | BranchHint hint = BranchHint::kNone) { |
| 29 | graph = g; |
| 30 | common = b; |
| 31 | branch = graph->NewNode(common->Branch(hint), cond, graph->start()); |
| 32 | if_true = graph->NewNode(common->IfTrue(), branch); |
| 33 | if_false = graph->NewNode(common->IfFalse(), branch); |
| 34 | merge = graph->NewNode(common->Merge(2), if_true, if_false); |
| 35 | } |
| 36 | |
| 37 | // Place {this} after {that} in control flow order. |
| 38 | void Chain(Diamond& that) { branch->ReplaceInput(1, that.merge); } |
| 39 | |
| 40 | // Place {this} after {that} in control flow order. |
| 41 | void Chain(Node* that) { branch->ReplaceInput(1, that); } |
| 42 | |
| 43 | // Nest {this} into either the if_true or if_false branch of {that}. |
| 44 | void Nest(Diamond& that, bool if_true) { |
| 45 | if (if_true) { |
| 46 | branch->ReplaceInput(1, that.if_true); |
| 47 | that.merge->ReplaceInput(0, merge); |
| 48 | } else { |
| 49 | branch->ReplaceInput(1, that.if_false); |
| 50 | that.merge->ReplaceInput(1, merge); |
| 51 | } |
| 52 | } |
| 53 | |
| 54 | Node* Phi(MachineType machine_type, Node* tv, Node* fv) { |
| 55 | return graph->NewNode(common->Phi(machine_type, 2), tv, fv, merge); |
| 56 | } |
| 57 | |
| 58 | Node* EffectPhi(Node* tv, Node* fv) { |
| 59 | return graph->NewNode(common->EffectPhi(2), tv, fv, merge); |
| 60 | } |
| 61 | |
| 62 | void OverwriteWithPhi(Node* node, MachineType machine_type, Node* tv, |
| 63 | Node* fv) { |
| 64 | DCHECK(node->InputCount() >= 3); |
| 65 | node->set_op(common->Phi(machine_type, 2)); |
| 66 | node->ReplaceInput(0, tv); |
| 67 | node->ReplaceInput(1, fv); |
| 68 | node->ReplaceInput(2, merge); |
| 69 | node->TrimInputCount(3); |
| 70 | } |
| 71 | |
| 72 | void OverwriteWithEffectPhi(Node* node, Node* te, Node* fe) { |
| 73 | DCHECK(node->InputCount() >= 3); |
| 74 | node->set_op(common->EffectPhi(2)); |
| 75 | node->ReplaceInput(0, te); |
| 76 | node->ReplaceInput(1, fe); |
| 77 | node->ReplaceInput(2, merge); |
| 78 | node->TrimInputCount(3); |
| 79 | } |
| 80 | }; |
| 81 | } |
| 82 | } |
| 83 | } // namespace v8::internal::compiler |
| 84 | |
| 85 | #endif // V8_COMPILER_DIAMOND_H_ |