DoWhileEmitter.cpp (1602B)
1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- 2 * vim: set ts=8 sts=2 et sw=2 tw=80: 3 * This Source Code Form is subject to the terms of the Mozilla Public 4 * License, v. 2.0. If a copy of the MPL was not distributed with this 5 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ 6 7 #include "frontend/DoWhileEmitter.h" 8 9 #include "frontend/BytecodeEmitter.h" 10 #include "vm/Opcodes.h" 11 #include "vm/StencilEnums.h" // TryNoteKind 12 13 using namespace js; 14 using namespace js::frontend; 15 16 DoWhileEmitter::DoWhileEmitter(BytecodeEmitter* bce) : bce_(bce) {} 17 18 bool DoWhileEmitter::emitBody(uint32_t doPos, uint32_t bodyPos) { 19 MOZ_ASSERT(state_ == State::Start); 20 21 // Ensure that the column of the 'do' is set properly. 22 if (!bce_->updateSourceCoordNotes(doPos)) { 23 return false; 24 } 25 26 // We need a nop here to make it possible to set a breakpoint on `do`. 27 if (!bce_->emit1(JSOp::Nop)) { 28 return false; 29 } 30 31 loopInfo_.emplace(bce_, StatementKind::DoLoop); 32 33 if (!loopInfo_->emitLoopHead(bce_, mozilla::Some(bodyPos))) { 34 return false; 35 } 36 37 #ifdef DEBUG 38 state_ = State::Body; 39 #endif 40 return true; 41 } 42 43 bool DoWhileEmitter::emitCond() { 44 MOZ_ASSERT(state_ == State::Body); 45 46 if (!loopInfo_->emitContinueTarget(bce_)) { 47 return false; 48 } 49 50 #ifdef DEBUG 51 state_ = State::Cond; 52 #endif 53 return true; 54 } 55 56 bool DoWhileEmitter::emitEnd() { 57 MOZ_ASSERT(state_ == State::Cond); 58 59 if (!loopInfo_->emitLoopEnd(bce_, JSOp::JumpIfTrue, TryNoteKind::Loop)) { 60 return false; 61 } 62 63 loopInfo_.reset(); 64 65 #ifdef DEBUG 66 state_ = State::End; 67 #endif 68 return true; 69 }