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Diffstat (limited to 'src/qml/jit/qv4blockscheduler_p.h')
| -rw-r--r-- | src/qml/jit/qv4blockscheduler_p.h | 155 |
1 files changed, 0 insertions, 155 deletions
diff --git a/src/qml/jit/qv4blockscheduler_p.h b/src/qml/jit/qv4blockscheduler_p.h deleted file mode 100644 index 1289fda9f0..0000000000 --- a/src/qml/jit/qv4blockscheduler_p.h +++ /dev/null @@ -1,155 +0,0 @@ -/**************************************************************************** -** -** Copyright (C) 2018 The Qt Company Ltd. -** Contact: https://www.qt.io/licensing/ -** -** This file is part of the QtQml module of the Qt Toolkit. -** -** $QT_BEGIN_LICENSE:LGPL$ -** Commercial License Usage -** Licensees holding valid commercial Qt licenses may use this file in -** accordance with the commercial license agreement provided with the -** Software or, alternatively, in accordance with the terms contained in -** a written agreement between you and The Qt Company. For licensing terms -** and conditions see https://www.qt.io/terms-conditions. For further -** information use the contact form at https://www.qt.io/contact-us. -** -** GNU Lesser General Public License Usage -** Alternatively, this file may be used under the terms of the GNU Lesser -** General Public License version 3 as published by the Free Software -** Foundation and appearing in the file LICENSE.LGPL3 included in the -** packaging of this file. Please review the following information to -** ensure the GNU Lesser General Public License version 3 requirements -** will be met: https://www.gnu.org/licenses/lgpl-3.0.html. -** -** GNU General Public License Usage -** Alternatively, this file may be used under the terms of the GNU -** General Public License version 2.0 or (at your option) the GNU General -** Public license version 3 or any later version approved by the KDE Free -** Qt Foundation. The licenses are as published by the Free Software -** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3 -** included in the packaging of this file. Please review the following -** information to ensure the GNU General Public License requirements will -** be met: https://www.gnu.org/licenses/gpl-2.0.html and -** https://www.gnu.org/licenses/gpl-3.0.html. -** -** $QT_END_LICENSE$ -** -****************************************************************************/ - -#ifndef QV4BLOCKSCHEDULER_P_H -#define QV4BLOCKSCHEDULER_P_H - -// -// W A R N I N G -// ------------- -// -// This file is not part of the Qt API. It exists purely as an -// implementation detail. This header file may change from version to -// version without notice, or even be removed. -// -// We mean it. -// - -#include <QtCore/qstack.h> - -#include "qv4mi_p.h" -#include "qv4util_p.h" - -QT_REQUIRE_CONFIG(qml_tracing); - -QT_BEGIN_NAMESPACE - -namespace QV4 { -namespace IR { - -class DominatorTree; -class LoopInfo; - -// High-level algorithm: -// 0. start with the first node (the start node) of a function -// 1. emit the node -// 2. add all outgoing edges that are not yet emitted to the postponed stack -// 3. When the postponed stack is empty, pop a stack from the loop stack. If that is empty too, -// we're done. -// 4. pop a node from the postponed stack, and check if it can be scheduled: -// a. if all incoming edges are scheduled, go to 4. -// b. if an incoming edge is unscheduled, but it's a back-edge (an edge in a loop that jumps -// back to the start of the loop), ignore it -// c. if there is any unscheduled edge that is not a back-edge, ignore this node, and go to 4. -// 5. if this node is the start of a loop, push the postponed stack on the loop stack. -// 6. go back to 1. -// -// The postponing action in step 2 will put the node into its containing group. The case where this -// is important is when a (labeled) continue or a (labeled) break statement occur in a loop: the -// outgoing edge points to a node that is not part of the current loop (and possibly not of the -// parent loop). -// -// Linear scan register allocation benefits greatly from short life-time intervals with few holes -// (see for example section 4 (Lifetime Analysis) of [Wimmer1]). This algorithm makes sure that the -// blocks of a group are scheduled together, with no non-loop blocks in between. This applies -// recursively for nested loops. It also schedules groups of if-then-else-endif blocks together for -// the same reason. -class BlockScheduler -{ - const DominatorTree &dominatorTree; - const LoopInfo &loopInfo; - - struct WorkForGroup - { - MIBlock *group; - QStack<MIBlock *> postponed; - - WorkForGroup(MIBlock *group = nullptr) : group(group) {} - }; - WorkForGroup currentGroup; - QStack<WorkForGroup> postponedGroups; - std::vector<MIBlock *> sequence; - - class ProcessedBlocks - { - BitVector processed; - - public: - ProcessedBlocks(MIFunction *function) - : processed(int(function->blockCount()), false) - {} - - bool alreadyProcessed(MIBlock *bb) const - { - Q_ASSERT(bb); - - return processed.at(bb->index()); - } - - void markAsProcessed(MIBlock *bb) - { - processed.setBit(bb->index()); - } - } emitted; - QHash<MIBlock *, MIBlock *> loopsStartEnd; - - bool checkCandidate(MIBlock *candidate); - MIBlock *pickNext(); - void emitBlock(MIBlock *bb); - void schedule(MIBlock *functionEntryPoint); - void postpone(MIBlock *bb); - void dump() const; - -public: - BlockScheduler(const DominatorTree &dominatorTree, const LoopInfo &loopInfo); - - const std::vector<MIBlock *> &scheduledBlockSequence() const - { return sequence; } - - QHash<MIBlock *, MIBlock *> loopEndsByStartBlock() const - { return loopsStartEnd; } -}; - - -} // namespace IR -} // namespace QV4 - -QT_END_NAMESPACE - -#endif // QV4BLOCKSCHEDULER_P_H |