qqmljsbasicblocks_p.h

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// Copyright (C) 2022 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR GPL-3.0-only WITH Qt-GPL-exception-1.0
// Qt-Security score:significant
 
#ifndef QQMLJSBASICBLOCKS_P_H
#define QQMLJSBASICBLOCKS_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 <private/qflatmap_p.h>
#include <private/qqmljscompilepass_p.h>
#include <private/qqmljscompiler_p.h>
 
QT_BEGIN_NAMESPACE
 
class Q_QMLCOMPILER_EXPORT QQmlJSBasicBlocks : public QQmlJSCompilePass
{
public:
    QQmlJSBasicBlocks(const QV4::Compiler::Context *context,
                      const QV4::Compiler::JSUnitGenerator *unitGenerator,
                      const QQmlJSTypeResolver *typeResolver, QQmlJSLogger *logger)
        : QQmlJSCompilePass(unitGenerator, typeResolver, logger), m_context{ context }
    {
    }
 
    ~QQmlJSBasicBlocks() = default;
 
    QQmlJSCompilePass::BlocksAndAnnotations run(const Function *function,
                                                QQmlJSAotCompiler::Flags compileFlags,
                                                bool &basicBlocksValidationFailed);
 
    struct BasicBlocksValidationResult { bool success = true; QString errorMessage; };
    BasicBlocksValidationResult basicBlocksValidation();
 
    static BasicBlocks::iterator basicBlockForInstruction(BasicBlocks &blocks, int offset)
    {
        return findBasicBlockForInstruction(blocks, offset);
    }
    static BasicBlocks::const_iterator constBasicBlockForInstruction(const BasicBlocks &blocks,
                                                                     int offset)
    {
        return findBasicBlockForInstruction(blocks, offset);
    }
 
    QList<ObjectOrArrayDefinition> objectAndArrayDefinitions() const;
 
private:
    QV4::Moth::ByteCodeHandler::Verdict startInstruction(QV4::Moth::Instr::Type type) override;
    void endInstruction(QV4::Moth::Instr::Type type) override;
 
    void generate_Jump(int offset) override;
    void generate_JumpTrue(int offset) override;
    void generate_JumpFalse(int offset) override;
    void generate_JumpNoException(int offset) override;
    void generate_JumpNotUndefined(int offset) override;
    void generate_IteratorNext(int value, int offset) override;
    void generate_GetOptionalLookup(int index, int offset) override;
 
    void generate_Ret() override;
    void generate_ThrowException() override;
 
    void generate_DefineArray(int argc, int argv) override;
    void generate_DefineObjectLiteral(int internalClassId, int argc, int args) override;
    void generate_Construct(int func, int argc, int argv) override;
 
    enum JumpMode { Unconditional, Conditional };
    void processJump(int offset, JumpMode mode);
 
    void dumpBasicBlocks();
    void dumpDOTGraph();
 
    template <typename Container, typename Iterator = decltype(Container().lower_bound(1))>
    static Iterator findBasicBlockForInstruction(Container &container, int instructionOffset)
    {
        auto block = container.lower_bound(instructionOffset);
        if (block == container.end() || block->first != instructionOffset)
            --block;
        return block;
    }
 
    const QV4::Compiler::Context *m_context;
    QList<ObjectOrArrayDefinition> m_objectAndArrayDefinitions;
    bool m_skipUntilNextLabel = false;
    bool m_hadBackJumps = false;
};
 
QT_END_NAMESPACE
 
#endif // QQMLJSBASICBLOCKS_P_H