From 2aa4a82499d4becd2284cdb482213d541b8804dd Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sun, 28 Apr 2024 16:29:10 +0200 Subject: Adding upstream version 86.0.1. Signed-off-by: Daniel Baumann --- js/src/frontend/BytecodeControlStructures.cpp | 111 ++++++++++++++++++++++++++ 1 file changed, 111 insertions(+) create mode 100644 js/src/frontend/BytecodeControlStructures.cpp (limited to 'js/src/frontend/BytecodeControlStructures.cpp') diff --git a/js/src/frontend/BytecodeControlStructures.cpp b/js/src/frontend/BytecodeControlStructures.cpp new file mode 100644 index 0000000000..401e27d8b2 --- /dev/null +++ b/js/src/frontend/BytecodeControlStructures.cpp @@ -0,0 +1,111 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- + * vim: set ts=8 sts=2 et sw=2 tw=80: + * This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +#include "frontend/BytecodeControlStructures.h" + +#include "frontend/BytecodeEmitter.h" // BytecodeEmitter +#include "frontend/EmitterScope.h" // EmitterScope +#include "vm/Opcodes.h" // JSOp + +using namespace js; +using namespace js::frontend; + +using mozilla::Maybe; + +NestableControl::NestableControl(BytecodeEmitter* bce, StatementKind kind) + : Nestable(&bce->innermostNestableControl), + kind_(kind), + emitterScope_(bce->innermostEmitterScopeNoCheck()) {} + +BreakableControl::BreakableControl(BytecodeEmitter* bce, StatementKind kind) + : NestableControl(bce, kind) { + MOZ_ASSERT(is()); +} + +bool BreakableControl::patchBreaks(BytecodeEmitter* bce) { + return bce->emitJumpTargetAndPatch(breaks); +} + +LabelControl::LabelControl(BytecodeEmitter* bce, const ParserAtom* label, + BytecodeOffset startOffset) + : BreakableControl(bce, StatementKind::Label), + label_(label), + startOffset_(startOffset) {} + +LoopControl::LoopControl(BytecodeEmitter* bce, StatementKind loopKind) + : BreakableControl(bce, loopKind), tdzCache_(bce) { + MOZ_ASSERT(is()); + + LoopControl* enclosingLoop = findNearest(enclosing()); + + stackDepth_ = bce->bytecodeSection().stackDepth(); + loopDepth_ = enclosingLoop ? enclosingLoop->loopDepth_ + 1 : 1; +} + +bool LoopControl::emitContinueTarget(BytecodeEmitter* bce) { + // Note: this is always called after emitting the loop body so we must have + // emitted all 'continues' by now. + return bce->emitJumpTargetAndPatch(continues); +} + +bool LoopControl::emitLoopHead(BytecodeEmitter* bce, + const Maybe& nextPos) { + // Insert a Nop if needed to ensure the script does not start with a + // JSOp::LoopHead. This avoids JIT issues with prologue code + try notes + // or OSR. See bug 1602390 and bug 1602681. + if (bce->bytecodeSection().offset().toUint32() == 0) { + if (!bce->emit1(JSOp::Nop)) { + return false; + } + } + + if (nextPos) { + if (!bce->updateSourceCoordNotes(*nextPos)) { + return false; + } + } + + MOZ_ASSERT(loopDepth_ > 0); + + head_ = {bce->bytecodeSection().offset()}; + + BytecodeOffset off; + if (!bce->emitJumpTargetOp(JSOp::LoopHead, &off)) { + return false; + } + SetLoopHeadDepthHint(bce->bytecodeSection().code(off), loopDepth_); + + return true; +} + +bool LoopControl::emitLoopEnd(BytecodeEmitter* bce, JSOp op, + TryNoteKind tryNoteKind) { + JumpList jump; + if (!bce->emitJumpNoFallthrough(op, &jump)) { + return false; + } + bce->patchJumpsToTarget(jump, head_); + + // Create a fallthrough for closing iterators, and as a target for break + // statements. + JumpTarget breakTarget; + if (!bce->emitJumpTarget(&breakTarget)) { + return false; + } + if (!patchBreaks(bce)) { + return false; + } + if (!bce->addTryNote(tryNoteKind, bce->bytecodeSection().stackDepth(), + headOffset(), breakTarget.offset)) { + return false; + } + return true; +} + +TryFinallyControl::TryFinallyControl(BytecodeEmitter* bce, StatementKind kind) + : NestableControl(bce, kind), emittingSubroutine_(false) { + MOZ_ASSERT(is()); +} -- cgit v1.2.3