//===-- Expression.h --------------------------------------------*- C++ -*-===//

//

// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.

// See https://llvm.org/LICENSE.txt for license information.

// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception

//

//===----------------------------------------------------------------------===//

#ifndef LLDB_EXPRESSION_EXPRESSION_H

#define LLDB_EXPRESSION_EXPRESSION_H

#include <map>

#include <string>

#include <vector>

#include "lldb/Expression/ExpressionTypeSystemHelper.h"

#include "lldb/lldb-forward.h"

#include "lldb/lldb-private.h"

namespace lldb_private {

/// \class Expression Expression.h "lldb/Expression/Expression.h" Encapsulates

/// a single expression for use in lldb

///

/// LLDB uses expressions for various purposes, notably to call functions

/// and as a backend for the expr command.  Expression encapsulates the

/// objects needed to parse and interpret or JIT an expression.  It uses the

/// expression parser appropriate to the language of the expression to produce

/// LLVM IR from the expression.

class Expression {

public:

  enum ResultType { eResultTypeAny, eResultTypeId };

  Expression(Target &target);

  Expression(ExecutionContextScope &exe_scope);

  /// Destructor

  virtual ~Expression() = default;

  /// Return the string that the parser should parse.  Must be a full

  /// translation unit.

  virtual const char *Text() = 0;

  /// Return the function name that should be used for executing the

  /// expression.  Text() should contain the definition of this function.

  virtual const char *FunctionName() = 0;

  /// Return the language that should be used when parsing.  To use the

  /// default, return eLanguageTypeUnknown.

  virtual lldb::LanguageType Language() const {

    return lldb::eLanguageTypeUnknown;

  }

  /// Return the Materializer that the parser should use when registering

  /// external values.

  virtual Materializer *GetMaterializer() { return nullptr; }

  /// Return the desired result type of the function, or eResultTypeAny if

  /// indifferent.

  virtual ResultType DesiredResultType() { return eResultTypeAny; }

  /// Flags

  /// Return true if validation code should be inserted into the expression.

  virtual bool NeedsValidation() = 0;

  /// Return true if external variables in the expression should be resolved.

  virtual bool NeedsVariableResolution() = 0;

  virtual EvaluateExpressionOptions *GetOptions() { return nullptr; };

  /// Return the address of the function's JIT-compiled code, or

  /// LLDB_INVALID_ADDRESS if the function is not JIT compiled

  lldb::addr_t StartAddress() { return m_jit_start_addr; }

  /// Called to notify the expression that it is about to be executed.

  virtual void WillStartExecuting() {}

  /// Called to notify the expression that its execution has finished.

  virtual void DidFinishExecuting() {}

  virtual ExpressionTypeSystemHelper *GetTypeSystemHelper() { return nullptr; }

  // LLVM RTTI support

  virtual bool isA(const void *ClassID) const = 0;

protected:

  lldb::TargetWP m_target_wp; /// Expression's always have to have a target...

  lldb::ProcessWP m_jit_process_wp; /// An expression might have a process, but

                                    /// it doesn't need to (e.g. calculator

                                    /// mode.)

  lldb::addr_t m_jit_start_addr; ///< The address of the JITted function within

                                 ///the JIT allocation.  LLDB_INVALID_ADDRESS if

                                 ///invalid.

  lldb::addr_t m_jit_end_addr;   ///< The address of the JITted function within

                                 ///the JIT allocation.  LLDB_INVALID_ADDRESS if

                                 ///invalid.

};

} // namespace lldb_private

#endif // LLDB_EXPRESSION_EXPRESSION_H