// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.
// See the LICENSE file in the project root for more information.

//
// State machine header used ONLY in the JIT.
//

#ifndef __sm_h__
#define __sm_h__

#include "smcommon.h"

extern const SMState*       gp_SMStates;
extern const JumpTableCell* gp_SMJumpTableCells;
extern const short*         gp_StateWeights;

class CodeSeqSM // Represent a particualr run of the state machine
                // For example, it maintains the array of counts for the terminated states.
                // These counts should be stored in per method based for them to be correct
                // under multithreadeded environment.
{
public:
    Compiler* pComp;

    const SMState*       States;
    const JumpTableCell* JumpTableCells;
    const short*         StateWeights; // Weight for each state. Including non-terminate states.

    SM_STATE_ID curState;

    int NativeSize; // This is a signed integer!

    void Start(Compiler* comp);
    void Reset();
    void End();
    void Run(SM_OPCODE opcode DEBUGARG(int level));

    SM_STATE_ID GetDestState(SM_STATE_ID srcState, SM_OPCODE opcode);

    // Matched a termination state
    inline void TermStateMatch(SM_STATE_ID stateID DEBUGARG(bool verbose))
    {
        assert(States[stateID].term);
#ifdef DEBUG
#ifndef SMGEN_COMPILE
        if (verbose)
        {
            printf("weight=%3d : state %3d [ %s ]\n", StateWeights[stateID], stateID, StateDesc(stateID));
        }
#endif // SMGEN_COMPILE
#endif // DEBUG

        NativeSize += StateWeights[stateID];
    }

    // Given an SM opcode retrieve the weight for this single opcode state.
    // For example, ID for single opcode state SM_NOSHOW is 2.
    inline short GetWeightForOpcode(SM_OPCODE opcode)
    {
        SM_STATE_ID stateID = ((SM_STATE_ID)opcode) + SM_STATE_ID_START + 1;
        return StateWeights[stateID];
    }

#ifdef DEBUG
    const char* StateDesc(SM_STATE_ID stateID);
#endif

    static SM_OPCODE MapToSMOpcode(OPCODE opcode);
};

#endif /* __sm_h__ */