src/scriptvm/ScriptVM.cpp

/*
 * Copyright (c) 2014 - 2020 Christian Schoenebeck
 *
 * http://www.linuxsampler.org
 *
 * This file is part of LinuxSampler and released under the same terms.
 * See README file for details.
 */

#include "ScriptVM.h"

#include <string.h>
#include <assert.h>
#include "../common/global_private.h"
#include "tree.h"
#include "CoreVMFunctions.h"
#include "CoreVMDynVars.h"
#include "editor/NkspScanner.h"

#define DEBUG_SCRIPTVM_CORE 0

/**
 * Maximum amount of VM instructions to be executed per ScriptVM::exec() call
 * in case loops are involved, before the script got automatically suspended
 * for a certain amount of time to avoid any RT instability issues.
 *
 * The following value takes a max. execution time of 300 microseconds as aimed
 * target, assuming an execution time of approximately 5 microseconds per
 * instruction this leads to the very approximate value set below.
 */
#define SCRIPTVM_MAX_INSTR_PER_CYCLE_SOFT 70

/**
 * Absolute maximum amount of VM instructions to be executed per
 * ScriptVM::exec() call (even if no loops are involved), before the script got
 * automatically suspended for a certain amount of time to avoid any RT
 * instability issues.
 *
 * A distinction between "soft" and "hard" limit is done here ATM because a
 * script author typically expects that his script might be interrupted
 * automatically if he is using while() loops, however he might not be
 * prepared that his script might also be interrupted if no loop is involved
 * (i.e. on very large scripts).
 *
 * The following value takes a max. execution time of 1000 microseconds as
 * aimed target, assuming an execution time of approximately 5 microseconds per
 * instruction this leads to the very approximate value set below.
 */
#define SCRIPTVM_MAX_INSTR_PER_CYCLE_HARD 210

/**
 * In case either SCRIPTVM_MAX_INSTR_PER_CYCLE_SOFT or
 * SCRIPTVM_MAX_INSTR_PER_CYCLE_HARD was exceeded when calling
 * ScriptVM::exec() : the amount of microseconds the respective script
 * execution instance should be automatically suspended by the VM.
 */
#define SCRIPT_VM_FORCE_SUSPENSION_MICROSECONDS 1000

int InstrScript_parse(LinuxSampler::ParserContext*);

namespace LinuxSampler {

    #if DEBUG_SCRIPTVM_CORE
    static void _printIndents(int n) {
        for (int i = 0; i < n; ++i) printf("  ");
        fflush(stdout);
    }
    #endif

    static vmint _requiredMaxStackSizeFor(Statement* statement, vmint depth = 0) {
        if (!statement) return 1;

        switch (statement->statementType()) {
            case STMT_LEAF:
                #if DEBUG_SCRIPTVM_CORE
                _printIndents(depth);
                printf("-> STMT_LEAF\n");
                #endif
                return 1;

            case STMT_LIST: {
                #if DEBUG_SCRIPTVM_CORE
                _printIndents(depth);
                printf("-> STMT_LIST\n");
                #endif
                Statements* stmts = (Statements*) statement;
                vmint max = 0;
                for (int i = 0; stmts->statement(i); ++i) {
                    vmint size = _requiredMaxStackSizeFor( stmts->statement(i), depth+1 );
                    if (max < size) max = size;
                }
                return max + 1;
            }

            case STMT_BRANCH: {
                #if DEBUG_SCRIPTVM_CORE
                _printIndents(depth);
                printf("-> STMT_BRANCH\n");
                #endif
                BranchStatement* branchStmt = (BranchStatement*) statement;
                vmint max = 0;
                for (int i = 0; branchStmt->branch(i); ++i) {
                    vmint size = _requiredMaxStackSizeFor( branchStmt->branch(i), depth+1 );
                    if (max < size) max = size;
                }
                return max + 1;
            }

            case STMT_LOOP: {
                #if DEBUG_SCRIPTVM_CORE
                _printIndents(depth);
                printf("-> STMT_LOOP\n");
                #endif
                While* whileStmt = (While*) statement;
                if (whileStmt->statements())
                    return _requiredMaxStackSizeFor( whileStmt->statements() ) + 1;
                else
                    return 1;
            }

            case STMT_SYNC: {
                #if DEBUG_SCRIPTVM_CORE
                _printIndents(depth);
                printf("-> STMT_SYNC\n");
                #endif
                SyncBlock* syncStmt = (SyncBlock*) statement;
                if (syncStmt->statements())
                    return _requiredMaxStackSizeFor( syncStmt->statements() ) + 1;
                else
                    return 1;
            }

            case STMT_NOOP:
                break; // no operation like the name suggests
        }

        return 1; // actually just to avoid compiler warning
    }

    static vmint _requiredMaxStackSizeFor(EventHandlers* handlers) {
        vmint max = 1;
        for (int i = 0; i < handlers->size(); ++i) {
            vmint size = _requiredMaxStackSizeFor(handlers->eventHandler(i));
            if (max < size) max = size;
        }
        return max;
    }

    ScriptVM::ScriptVM() :
        m_eventHandler(NULL), m_parserContext(NULL), m_autoSuspend(true),
        m_acceptExitRes(false)
    {
        m_fnMessage = new CoreVMFunction_message;
        m_fnExit = new CoreVMFunction_exit(this);
        m_fnWait = new CoreVMFunction_wait(this);
        m_fnAbs = new CoreVMFunction_abs;
        m_fnRandom = new CoreVMFunction_random;
        m_fnNumElements = new CoreVMFunction_num_elements;
        m_fnInc = new CoreVMFunction_inc;
        m_fnDec = new CoreVMFunction_dec;
        m_fnInRange = new CoreVMFunction_in_range;
        m_varRealTimer = new CoreVMDynVar_NKSP_REAL_TIMER;
        m_varPerfTimer = new CoreVMDynVar_NKSP_PERF_TIMER;
        m_fnShLeft = new CoreVMFunction_sh_left;
        m_fnShRight = new CoreVMFunction_sh_right;
        m_fnMsb = new CoreVMFunction_msb;
        m_fnLsb = new CoreVMFunction_lsb;
        m_fnMin = new CoreVMFunction_min;
        m_fnMax = new CoreVMFunction_max;
        m_fnArrayEqual = new CoreVMFunction_array_equal;
        m_fnSearch = new CoreVMFunction_search;
        m_fnSort = new CoreVMFunction_sort;
        m_fnIntToReal = new CoreVMFunction_int_to_real;
        m_fnRealToInt = new CoreVMFunction_real_to_int;
        m_fnRound = new CoreVMFunction_round;
        m_fnCeil = new CoreVMFunction_ceil;
        m_fnFloor = new CoreVMFunction_floor;
        m_fnSqrt = new CoreVMFunction_sqrt;
        m_fnLog = new CoreVMFunction_log;
        m_fnLog2 = new CoreVMFunction_log2;
        m_fnLog10 = new CoreVMFunction_log10;
        m_fnExp = new CoreVMFunction_exp;
        m_fnPow = new CoreVMFunction_pow;
        m_fnSin = new CoreVMFunction_sin;
        m_fnCos = new CoreVMFunction_cos;
        m_fnTan = new CoreVMFunction_tan;
        m_fnAsin = new CoreVMFunction_asin;
        m_fnAcos = new CoreVMFunction_acos;
        m_fnAtan = new CoreVMFunction_atan;
    }

    ScriptVM::~ScriptVM() {
        delete m_fnMessage;
        delete m_fnExit;
        delete m_fnWait;
        delete m_fnAbs;
        delete m_fnRandom;
        delete m_fnNumElements;
        delete m_fnInc;
        delete m_fnDec;
        delete m_fnInRange;
        delete m_fnShLeft;
        delete m_fnShRight;
        delete m_fnMsb;
        delete m_fnLsb;
        delete m_fnMin;
        delete m_fnMax;
        delete m_fnArrayEqual;
        delete m_fnSearch;
        delete m_fnSort;
        delete m_fnIntToReal;
        delete m_fnRealToInt;
        delete m_fnRound;
        delete m_fnCeil;
        delete m_fnFloor;
        delete m_fnSqrt;
        delete m_fnLog;
        delete m_fnLog2;
        delete m_fnLog10;
        delete m_fnExp;
        delete m_fnPow;
        delete m_fnSin;
        delete m_fnCos;
        delete m_fnTan;
        delete m_fnAsin;
        delete m_fnAcos;
        delete m_fnAtan;
        delete m_varRealTimer;
        delete m_varPerfTimer;
    }

    VMParserContext* ScriptVM::loadScript(const String& s) {
        std::istringstream iss(s);
        return loadScript(&iss);
    }
    
    VMParserContext* ScriptVM::loadScript(std::istream* is) {
        ParserContext* context = new ParserContext(this);
        //printf("parserCtx=0x%lx\n", (uint64_t)context);

        context->registerBuiltInConstIntVariables( builtInConstIntVariables() );
        context->registerBuiltInConstRealVariables( builtInConstRealVariables() );
        context->registerBuiltInIntVariables( builtInIntVariables() );
        context->registerBuiltInIntArrayVariables( builtInIntArrayVariables() );
        context->registerBuiltInDynVariables( builtInDynamicVariables() );

        context->createScanner(is);

        InstrScript_parse(context);
        dmsg(2,("Allocating %lld bytes of global int VM memory.\n", context->globalIntVarCount * sizeof(vmint)));
        dmsg(2,("Allocating %lld bytes of global real VM memory.\n", context->globalRealVarCount * sizeof(vmfloat)));
        dmsg(2,("Allocating %lld bytes of global unit factor VM memory.\n", context->globalUnitFactorCount * sizeof(vmfloat)));
        dmsg(2,("Allocating %lld of global VM string variables.\n", context->globalStrVarCount));
        if (!context->globalIntMemory)
            context->globalIntMemory = new ArrayList<vmint>();
        if (!context->globalRealMemory)
            context->globalRealMemory = new ArrayList<vmfloat>();
        if (!context->globalUnitFactorMemory)
            context->globalUnitFactorMemory = new ArrayList<vmfloat>();
        if (!context->globalStrMemory)
            context->globalStrMemory = new ArrayList<String>();
        context->globalIntMemory->resize(context->globalIntVarCount);
        context->globalRealMemory->resize(context->globalRealVarCount);
        context->globalUnitFactorMemory->resize(context->globalUnitFactorCount);
        memset(&((*context->globalIntMemory)[0]), 0, context->globalIntVarCount * sizeof(vmint));
        memset(&((*context->globalRealMemory)[0]), 0, context->globalRealVarCount * sizeof(vmfloat));
        for (vmint i = 0; i < context->globalUnitFactorCount; ++i)
            (*context->globalUnitFactorMemory)[i] = VM_NO_FACTOR;
        context->globalStrMemory->resize(context->globalStrVarCount);

        context->destroyScanner();

        return context;
    }

    void ScriptVM::dumpParsedScript(VMParserContext* context) {
        ParserContext* ctx = dynamic_cast<ParserContext*>(context);
        if (!ctx) {
            std::cerr << "No VM context. So nothing to dump.\n";
            return;
        }
        if (!ctx->handlers) {
            std::cerr << "No event handlers defined in script. So nothing to dump.\n";
            return;
        }
        if (!ctx->globalIntMemory) {
            std::cerr << "Internal error: no global integer memory assigend to script VM.\n";
            return;
        }
        if (!ctx->globalRealMemory) {
            std::cerr << "Internal error: no global real number memory assigend to script VM.\n";
            return;
        }
        ctx->handlers->dump();
    }

    VMExecContext* ScriptVM::createExecContext(VMParserContext* parserContext) {
        ParserContext* parserCtx = dynamic_cast<ParserContext*>(parserContext);
        ExecContext* execCtx = new ExecContext();
        
        if (parserCtx->requiredMaxStackSize < 0) {
             parserCtx->requiredMaxStackSize =
                _requiredMaxStackSizeFor(&*parserCtx->handlers);
        }
        execCtx->stack.resize(parserCtx->requiredMaxStackSize);
        dmsg(2,("Created VM exec context with %lld bytes VM stack size.\n",
                parserCtx->requiredMaxStackSize * sizeof(ExecContext::StackFrame)));
        //printf("execCtx=0x%lx\n", (uint64_t)execCtx);
        const vmint polyIntSize = parserCtx->polyphonicIntVarCount;
        execCtx->polyphonicIntMemory.resize(polyIntSize);
        memset(&execCtx->polyphonicIntMemory[0], 0, polyIntSize * sizeof(vmint));

        const vmint polyRealSize = parserCtx->polyphonicRealVarCount;
        execCtx->polyphonicRealMemory.resize(polyRealSize);
        memset(&execCtx->polyphonicRealMemory[0], 0, polyRealSize * sizeof(vmfloat));

        const vmint polyFactorSize = parserCtx->polyphonicUnitFactorCount;
        execCtx->polyphonicUnitFactorMemory.resize(polyFactorSize);
        for (vmint i = 0; i < polyFactorSize; ++i)
            execCtx->polyphonicUnitFactorMemory[i] = VM_NO_FACTOR;

        dmsg(2,("Allocated %lld bytes polyphonic int memory.\n", polyIntSize * sizeof(vmint)));
        dmsg(2,("Allocated %lld bytes polyphonic real memory.\n", polyRealSize * sizeof(vmfloat)));
        dmsg(2,("Allocated %lld bytes unit factor memory.\n", polyFactorSize * sizeof(vmfloat)));
        return execCtx;
    }

    std::vector<VMSourceToken> ScriptVM::syntaxHighlighting(const String& s) {
        std::istringstream iss(s);
        return syntaxHighlighting(&iss);
    }

    std::vector<VMSourceToken> ScriptVM::syntaxHighlighting(std::istream* is) {
        try {
            NkspScanner scanner(is);
            std::vector<SourceToken> tokens = scanner.tokens();
            std::vector<VMSourceToken> result;
            result.resize(tokens.size());
            for (vmint i = 0; i < tokens.size(); ++i) {
                SourceToken* st = new SourceToken;
                *st = tokens[i];
                result[i] = VMSourceToken(st);
            }
            return result;
        } catch (...) {
            return std::vector<VMSourceToken>();
        }
    }

    VMFunction* ScriptVM::functionByName(const String& name) {
        if (name == "message") return m_fnMessage;
        else if (name == "exit") return m_fnExit;
        else if (name == "wait") return m_fnWait;
        else if (name == "abs") return m_fnAbs;
        else if (name == "random") return m_fnRandom;
        else if (name == "num_elements") return m_fnNumElements;
        else if (name == "inc") return m_fnInc;
        else if (name == "dec") return m_fnDec;
        else if (name == "in_range") return m_fnInRange;
        else if (name == "sh_left") return m_fnShLeft;
        else if (name == "sh_right") return m_fnShRight;
        else if (name == "msb") return m_fnMsb;
        else if (name == "lsb") return m_fnLsb;
        else if (name == "min") return m_fnMin;
        else if (name == "max") return m_fnMax;
        else if (name == "array_equal") return m_fnArrayEqual;
        else if (name == "search") return m_fnSearch;
        else if (name == "sort") return m_fnSort;
        else if (name == "int_to_real") return m_fnIntToReal;
        else if (name == "real") return m_fnIntToReal;
        else if (name == "real_to_int") return m_fnRealToInt;
        else if (name == "int") return m_fnRealToInt;
        else if (name == "round") return m_fnRound;
        else if (name == "ceil") return m_fnCeil;
        else if (name == "floor") return m_fnFloor;
        else if (name == "sqrt") return m_fnSqrt;
        else if (name == "log") return m_fnLog;
        else if (name == "log2") return m_fnLog2;
        else if (name == "log10") return m_fnLog10;
        else if (name == "exp") return m_fnExp;
        else if (name == "pow") return m_fnPow;
        else if (name == "sin") return m_fnSin;
        else if (name == "cos") return m_fnCos;
        else if (name == "tan") return m_fnTan;
        else if (name == "asin") return m_fnAsin;
        else if (name == "acos") return m_fnAcos;
        else if (name == "atan") return m_fnAtan;
        return NULL;
    }

    bool ScriptVM::isFunctionDisabled(VMFunction* fn, VMParserContext* ctx) {
        ParserContext* parserCtx = dynamic_cast<ParserContext*>(ctx);
        if (!parserCtx) return false;

        if (fn == m_fnMessage && parserCtx->userPreprocessorConditions.count("NKSP_NO_MESSAGE"))
            return true;

        return false;
    }

    std::map<String,VMIntPtr*> ScriptVM::builtInIntVariables() {
        return std::map<String,VMIntPtr*>();
    }

    std::map<String,VMInt8Array*> ScriptVM::builtInIntArrayVariables() {
        return std::map<String,VMInt8Array*>();
    }

    std::map<String,VMDynVar*> ScriptVM::builtInDynamicVariables() {
        std::map<String,VMDynVar*> m;

        m["$NKSP_PERF_TIMER"] = m_varPerfTimer;
        m["$NKSP_REAL_TIMER"] = m_varRealTimer;
        m["$KSP_TIMER"] = m_varRealTimer;

        return m;
    }

    std::map<String,vmint> ScriptVM::builtInConstIntVariables() {
        std::map<String,vmint> m;

        m["$NI_CB_TYPE_INIT"] = VM_EVENT_HANDLER_INIT;
        m["$NI_CB_TYPE_NOTE"] = VM_EVENT_HANDLER_NOTE;
        m["$NI_CB_TYPE_RELEASE"] = VM_EVENT_HANDLER_RELEASE;
        m["$NI_CB_TYPE_CONTROLLER"] = VM_EVENT_HANDLER_CONTROLLER;
        m["$NI_CB_TYPE_RPN"] = VM_EVENT_HANDLER_RPN;
        m["$NI_CB_TYPE_NRPN"] = VM_EVENT_HANDLER_NRPN;

        return m;
    }

    std::map<String,vmfloat> ScriptVM::builtInConstRealVariables() {
        std::map<String,vmfloat> m;

        m["~NI_MATH_PI"] = M_PI;
        m["~NI_MATH_E"] = M_E;

        return m;
    }

    VMEventHandler* ScriptVM::currentVMEventHandler() {
        return m_eventHandler;
    }

    VMParserContext* ScriptVM::currentVMParserContext() {
        return m_parserContext;
    }

    VMExecContext* ScriptVM::currentVMExecContext() {
        if (!m_parserContext) return NULL;
        return m_parserContext->execContext;
    }

    void ScriptVM::setAutoSuspendEnabled(bool b) {
        m_autoSuspend = b;
    }

    bool ScriptVM::isAutoSuspendEnabled() const {
        return m_autoSuspend;
    }

    void ScriptVM::setExitResultEnabled(bool b) {
        m_acceptExitRes = b;
    }

    bool ScriptVM::isExitResultEnabled() const {
        return m_acceptExitRes;
    }

    VMExecStatus_t ScriptVM::exec(VMParserContext* parserContext, VMExecContext* execContex, VMEventHandler* handler) {
        m_parserContext = dynamic_cast<ParserContext*>(parserContext);
        if (!m_parserContext) {
            std::cerr << "No VM parser context provided. Did you load a script?\n";
            return VMExecStatus_t(VM_EXEC_NOT_RUNNING | VM_EXEC_ERROR);
        }

        // a ParserContext object is always tied to exactly one ScriptVM object
        assert(m_parserContext->functionProvider == this);

        ExecContext* ctx = dynamic_cast<ExecContext*>(execContex);
        if (!ctx) {
            std::cerr << "Invalid VM exec context.\n";
            return VMExecStatus_t(VM_EXEC_NOT_RUNNING | VM_EXEC_ERROR);
        }
        EventHandler* h = dynamic_cast<EventHandler*>(handler);
        if (!h) return VM_EXEC_NOT_RUNNING;
        m_eventHandler = handler;

        m_parserContext->execContext = ctx;

        ctx->status = VM_EXEC_RUNNING;
        ctx->instructionsCount = 0;
        ctx->clearExitRes();
        StmtFlags_t& flags = ctx->flags;
        vmint instructionsCounter = 0;
        vmint synced = m_autoSuspend ? 0 : 1;

        int& frameIdx = ctx->stackFrame;
        if (frameIdx < 0) { // start condition ...
            frameIdx = -1;
            ctx->pushStack(h);
        }

        while (flags == STMT_SUCCESS && frameIdx >= 0) {
            if (frameIdx >= ctx->stack.size()) { // should never happen, otherwise it's a bug ...
                std::cerr << "CRITICAL: VM stack overflow! (" << frameIdx << ")\n";
                flags = StmtFlags_t(STMT_ABORT_SIGNALLED | STMT_ERROR_OCCURRED);
                break;
            }

            ExecContext::StackFrame& frame = ctx->stack[frameIdx];
            switch (frame.statement->statementType()) {
                case STMT_LEAF: {
                    #if DEBUG_SCRIPTVM_CORE
                    _printIndents(frameIdx);
                    printf("-> STMT_LEAF\n");
                    #endif
                    LeafStatement* leaf = (LeafStatement*) frame.statement;
                    flags = leaf->exec();
                    ctx->popStack();
                    break;
                }

                case STMT_LIST: {
                    #if DEBUG_SCRIPTVM_CORE
                    _printIndents(frameIdx);
                    printf("-> STMT_LIST subidx=%d\n", frame.subindex);
                    #endif
                    Statements* stmts = (Statements*) frame.statement;
                    if (stmts->statement(frame.subindex)) {
                        ctx->pushStack(
                            stmts->statement(frame.subindex++)
                        );
                    } else {
                        #if DEBUG_SCRIPTVM_CORE
                        _printIndents(frameIdx);
                        printf("[END OF LIST] subidx=%d\n", frame.subindex);
                        #endif
                        ctx->popStack();
                    }
                    break;
                }

                case STMT_BRANCH: {
                    #if DEBUG_SCRIPTVM_CORE
                    _printIndents(frameIdx);
                    printf("-> STMT_BRANCH\n");
                    #endif
                    if (frame.subindex < 0) ctx->popStack();
                    else {
                        BranchStatement* branchStmt = (BranchStatement*) frame.statement;
                        frame.subindex =
                            (decltype(frame.subindex))
                                branchStmt->evalBranch();
                        if (frame.subindex >= 0) {
                            ctx->pushStack(
                                branchStmt->branch(frame.subindex)
                            );
                            frame.subindex = -1;
                        } else ctx->popStack();
                    }
                    break;
                }

                case STMT_LOOP: {
                    #if DEBUG_SCRIPTVM_CORE
                    _printIndents(frameIdx);
                    printf("-> STMT_LOOP\n");
                    #endif
                    While* whileStmt = (While*) frame.statement;
                    if (whileStmt->evalLoopStartCondition() && whileStmt->statements()) {
                        ctx->pushStack(
                            whileStmt->statements()
                        );
                        if (flags == STMT_SUCCESS && !synced &&
                            instructionsCounter > SCRIPTVM_MAX_INSTR_PER_CYCLE_SOFT)
                        {
                            flags = StmtFlags_t(STMT_SUSPEND_SIGNALLED);
                            ctx->suspendMicroseconds = SCRIPT_VM_FORCE_SUSPENSION_MICROSECONDS;
                        }
                    } else ctx->popStack();
                    break;
                }

                case STMT_SYNC: {
                    #if DEBUG_SCRIPTVM_CORE
                    _printIndents(frameIdx);
                    printf("-> STMT_SYNC\n");
                    #endif
                    SyncBlock* syncStmt = (SyncBlock*) frame.statement;
                    if (!frame.subindex++ && syncStmt->statements()) {
                        ++synced;
                        ctx->pushStack(
                            syncStmt->statements()
                        );
                    } else {
                        ctx->popStack();
                        --synced;
                    }
                    break;
                }

                case STMT_NOOP:
                    break; // no operation like the name suggests
            }

            if (flags == STMT_SUCCESS && !synced &&
                instructionsCounter > SCRIPTVM_MAX_INSTR_PER_CYCLE_HARD)
            {
                flags = StmtFlags_t(STMT_SUSPEND_SIGNALLED);
                ctx->suspendMicroseconds = SCRIPT_VM_FORCE_SUSPENSION_MICROSECONDS;
            }

            ++instructionsCounter;
        }

        if ((flags & STMT_SUSPEND_SIGNALLED) && !(flags & STMT_ABORT_SIGNALLED)) {
            ctx->status = VM_EXEC_SUSPENDED;
            ctx->flags  = STMT_SUCCESS;
        } else {
            ctx->status = VM_EXEC_NOT_RUNNING;
            if (flags & STMT_ERROR_OCCURRED)
                ctx->status = VM_EXEC_ERROR;
            ctx->reset();
        }

        ctx->instructionsCount = instructionsCounter;

        m_eventHandler = NULL;
        m_parserContext->execContext = NULL;
        m_parserContext = NULL;
        return ctx->status;
    }

} // namespace LinuxSampler
1	/*
2	* Copyright (c) 2014 - 2020 Christian Schoenebeck
3	*
4	* http://www.linuxsampler.org
5	*
6	* This file is part of LinuxSampler and released under the same terms.
7	* See README file for details.
8	*/
9
10	#include "ScriptVM.h"
11
12	#include <string.h>
13	#include <assert.h>
14	#include "../common/global_private.h"
15	#include "tree.h"
16	#include "CoreVMFunctions.h"
17	#include "CoreVMDynVars.h"
18	#include "editor/NkspScanner.h"
19
20	#define DEBUG_SCRIPTVM_CORE 0
21
22	/**
23	* Maximum amount of VM instructions to be executed per ScriptVM::exec() call
24	* in case loops are involved, before the script got automatically suspended
25	* for a certain amount of time to avoid any RT instability issues.
26	*
27	* The following value takes a max. execution time of 300 microseconds as aimed
28	* target, assuming an execution time of approximately 5 microseconds per
29	* instruction this leads to the very approximate value set below.
30	*/
31	#define SCRIPTVM_MAX_INSTR_PER_CYCLE_SOFT 70
32
33	/**
34	* Absolute maximum amount of VM instructions to be executed per
35	* ScriptVM::exec() call (even if no loops are involved), before the script got
36	* automatically suspended for a certain amount of time to avoid any RT
37	* instability issues.
38	*
39	* A distinction between "soft" and "hard" limit is done here ATM because a
40	* script author typically expects that his script might be interrupted
41	* automatically if he is using while() loops, however he might not be
42	* prepared that his script might also be interrupted if no loop is involved
43	* (i.e. on very large scripts).
44	*
45	* The following value takes a max. execution time of 1000 microseconds as
46	* aimed target, assuming an execution time of approximately 5 microseconds per
47	* instruction this leads to the very approximate value set below.
48	*/
49	#define SCRIPTVM_MAX_INSTR_PER_CYCLE_HARD 210
50
51	/**
52	* In case either SCRIPTVM_MAX_INSTR_PER_CYCLE_SOFT or
53	* SCRIPTVM_MAX_INSTR_PER_CYCLE_HARD was exceeded when calling
54	* ScriptVM::exec() : the amount of microseconds the respective script
55	* execution instance should be automatically suspended by the VM.
56	*/
57	#define SCRIPT_VM_FORCE_SUSPENSION_MICROSECONDS 1000
58
59	int InstrScript_parse(LinuxSampler::ParserContext*);
60
61	namespace LinuxSampler {
62
63	#if DEBUG_SCRIPTVM_CORE
64	static void _printIndents(int n) {
65	for (int i = 0; i < n; ++i) printf(" ");
66	fflush(stdout);
67	}
68	#endif
69
70	static vmint _requiredMaxStackSizeFor(Statement* statement, vmint depth = 0) {
71	if (!statement) return 1;
72
73	switch (statement->statementType()) {
74	case STMT_LEAF:
75	#if DEBUG_SCRIPTVM_CORE
76	_printIndents(depth);
77	printf("-> STMT_LEAF\n");
78	#endif
79	return 1;
80
81	case STMT_LIST: {
82	#if DEBUG_SCRIPTVM_CORE
83	_printIndents(depth);
84	printf("-> STMT_LIST\n");
85	#endif
86	Statements* stmts = (Statements*) statement;
87	vmint max = 0;
88	for (int i = 0; stmts->statement(i); ++i) {
89	vmint size = _requiredMaxStackSizeFor( stmts->statement(i), depth+1 );
90	if (max < size) max = size;
91	}
92	return max + 1;
93	}
94
95	case STMT_BRANCH: {
96	#if DEBUG_SCRIPTVM_CORE
97	_printIndents(depth);
98	printf("-> STMT_BRANCH\n");
99	#endif
100	BranchStatement* branchStmt = (BranchStatement*) statement;
101	vmint max = 0;
102	for (int i = 0; branchStmt->branch(i); ++i) {
103	vmint size = _requiredMaxStackSizeFor( branchStmt->branch(i), depth+1 );
104	if (max < size) max = size;
105	}
106	return max + 1;
107	}
108
109	case STMT_LOOP: {
110	#if DEBUG_SCRIPTVM_CORE
111	_printIndents(depth);
112	printf("-> STMT_LOOP\n");
113	#endif
114	While* whileStmt = (While*) statement;
115	if (whileStmt->statements())
116	return _requiredMaxStackSizeFor( whileStmt->statements() ) + 1;
117	else
118	return 1;
119	}
120
121	case STMT_SYNC: {
122	#if DEBUG_SCRIPTVM_CORE
123	_printIndents(depth);
124	printf("-> STMT_SYNC\n");
125	#endif
126	SyncBlock* syncStmt = (SyncBlock*) statement;
127	if (syncStmt->statements())
128	return _requiredMaxStackSizeFor( syncStmt->statements() ) + 1;
129	else
130	return 1;
131	}
132
133	case STMT_NOOP:
134	break; // no operation like the name suggests
135	}
136
137	return 1; // actually just to avoid compiler warning
138	}
139
140	static vmint _requiredMaxStackSizeFor(EventHandlers* handlers) {
141	vmint max = 1;
142	for (int i = 0; i < handlers->size(); ++i) {
143	vmint size = _requiredMaxStackSizeFor(handlers->eventHandler(i));
144	if (max < size) max = size;
145	}
146	return max;
147	}
148
149	ScriptVM::ScriptVM() :
150	m_eventHandler(NULL), m_parserContext(NULL), m_autoSuspend(true),
151	m_acceptExitRes(false)
152	{
153	m_fnMessage = new CoreVMFunction_message;
154	m_fnExit = new CoreVMFunction_exit(this);
155	m_fnWait = new CoreVMFunction_wait(this);
156	m_fnAbs = new CoreVMFunction_abs;
157	m_fnRandom = new CoreVMFunction_random;
158	m_fnNumElements = new CoreVMFunction_num_elements;
159	m_fnInc = new CoreVMFunction_inc;
160	m_fnDec = new CoreVMFunction_dec;
161	m_fnInRange = new CoreVMFunction_in_range;
162	m_varRealTimer = new CoreVMDynVar_NKSP_REAL_TIMER;
163	m_varPerfTimer = new CoreVMDynVar_NKSP_PERF_TIMER;
164	m_fnShLeft = new CoreVMFunction_sh_left;
165	m_fnShRight = new CoreVMFunction_sh_right;
166	m_fnMsb = new CoreVMFunction_msb;
167	m_fnLsb = new CoreVMFunction_lsb;
168	m_fnMin = new CoreVMFunction_min;
169	m_fnMax = new CoreVMFunction_max;
170	m_fnArrayEqual = new CoreVMFunction_array_equal;
171	m_fnSearch = new CoreVMFunction_search;
172	m_fnSort = new CoreVMFunction_sort;
173	m_fnIntToReal = new CoreVMFunction_int_to_real;
174	m_fnRealToInt = new CoreVMFunction_real_to_int;
175	m_fnRound = new CoreVMFunction_round;
176	m_fnCeil = new CoreVMFunction_ceil;
177	m_fnFloor = new CoreVMFunction_floor;
178	m_fnSqrt = new CoreVMFunction_sqrt;
179	m_fnLog = new CoreVMFunction_log;
180	m_fnLog2 = new CoreVMFunction_log2;
181	m_fnLog10 = new CoreVMFunction_log10;
182	m_fnExp = new CoreVMFunction_exp;
183	m_fnPow = new CoreVMFunction_pow;
184	m_fnSin = new CoreVMFunction_sin;
185	m_fnCos = new CoreVMFunction_cos;
186	m_fnTan = new CoreVMFunction_tan;
187	m_fnAsin = new CoreVMFunction_asin;
188	m_fnAcos = new CoreVMFunction_acos;
189	m_fnAtan = new CoreVMFunction_atan;
190	}
191
192	ScriptVM::~ScriptVM() {
193	delete m_fnMessage;
194	delete m_fnExit;
195	delete m_fnWait;
196	delete m_fnAbs;
197	delete m_fnRandom;
198	delete m_fnNumElements;
199	delete m_fnInc;
200	delete m_fnDec;
201	delete m_fnInRange;
202	delete m_fnShLeft;
203	delete m_fnShRight;
204	delete m_fnMsb;
205	delete m_fnLsb;
206	delete m_fnMin;
207	delete m_fnMax;
208	delete m_fnArrayEqual;
209	delete m_fnSearch;
210	delete m_fnSort;
211	delete m_fnIntToReal;
212	delete m_fnRealToInt;
213	delete m_fnRound;
214	delete m_fnCeil;
215	delete m_fnFloor;
216	delete m_fnSqrt;
217	delete m_fnLog;
218	delete m_fnLog2;
219	delete m_fnLog10;
220	delete m_fnExp;
221	delete m_fnPow;
222	delete m_fnSin;
223	delete m_fnCos;
224	delete m_fnTan;
225	delete m_fnAsin;
226	delete m_fnAcos;
227	delete m_fnAtan;
228	delete m_varRealTimer;
229	delete m_varPerfTimer;
230	}
231
232	VMParserContext* ScriptVM::loadScript(const String& s) {
233	std::istringstream iss(s);
234	return loadScript(&iss);
235	}
236
237	VMParserContext* ScriptVM::loadScript(std::istream* is) {
238	ParserContext* context = new ParserContext(this);
239	//printf("parserCtx=0x%lx\n", (uint64_t)context);
240
241	context->registerBuiltInConstIntVariables( builtInConstIntVariables() );
242	context->registerBuiltInConstRealVariables( builtInConstRealVariables() );
243	context->registerBuiltInIntVariables( builtInIntVariables() );
244	context->registerBuiltInIntArrayVariables( builtInIntArrayVariables() );
245	context->registerBuiltInDynVariables( builtInDynamicVariables() );
246
247	context->createScanner(is);
248
249	InstrScript_parse(context);
250	dmsg(2,("Allocating %lld bytes of global int VM memory.\n", context->globalIntVarCount * sizeof(vmint)));
251	dmsg(2,("Allocating %lld bytes of global real VM memory.\n", context->globalRealVarCount * sizeof(vmfloat)));
252	dmsg(2,("Allocating %lld bytes of global unit factor VM memory.\n", context->globalUnitFactorCount * sizeof(vmfloat)));
253	dmsg(2,("Allocating %lld of global VM string variables.\n", context->globalStrVarCount));
254	if (!context->globalIntMemory)
255	context->globalIntMemory = new ArrayList<vmint>();
256	if (!context->globalRealMemory)
257	context->globalRealMemory = new ArrayList<vmfloat>();
258	if (!context->globalUnitFactorMemory)
259	context->globalUnitFactorMemory = new ArrayList<vmfloat>();
260	if (!context->globalStrMemory)
261	context->globalStrMemory = new ArrayList<String>();
262	context->globalIntMemory->resize(context->globalIntVarCount);
263	context->globalRealMemory->resize(context->globalRealVarCount);
264	context->globalUnitFactorMemory->resize(context->globalUnitFactorCount);
265	memset(&((context->globalIntMemory)[0]), 0, context->globalIntVarCount sizeof(vmint));
266	memset(&((context->globalRealMemory)[0]), 0, context->globalRealVarCount sizeof(vmfloat));
267	for (vmint i = 0; i < context->globalUnitFactorCount; ++i)
268	(*context->globalUnitFactorMemory)[i] = VM_NO_FACTOR;
269	context->globalStrMemory->resize(context->globalStrVarCount);
270
271	context->destroyScanner();
272
273	return context;
274	}
275
276	void ScriptVM::dumpParsedScript(VMParserContext* context) {
277	ParserContext* ctx = dynamic_cast<ParserContext*>(context);
278	if (!ctx) {
279	std::cerr << "No VM context. So nothing to dump.\n";
280	return;
281	}
282	if (!ctx->handlers) {
283	std::cerr << "No event handlers defined in script. So nothing to dump.\n";
284	return;
285	}
286	if (!ctx->globalIntMemory) {
287	std::cerr << "Internal error: no global integer memory assigend to script VM.\n";
288	return;
289	}
290	if (!ctx->globalRealMemory) {
291	std::cerr << "Internal error: no global real number memory assigend to script VM.\n";
292	return;
293	}
294	ctx->handlers->dump();
295	}
296
297	VMExecContext* ScriptVM::createExecContext(VMParserContext* parserContext) {
298	ParserContext* parserCtx = dynamic_cast<ParserContext*>(parserContext);
299	ExecContext* execCtx = new ExecContext();
300
301	if (parserCtx->requiredMaxStackSize < 0) {
302	parserCtx->requiredMaxStackSize =
303	_requiredMaxStackSizeFor(&*parserCtx->handlers);
304	}
305	execCtx->stack.resize(parserCtx->requiredMaxStackSize);
306	dmsg(2,("Created VM exec context with %lld bytes VM stack size.\n",
307	parserCtx->requiredMaxStackSize * sizeof(ExecContext::StackFrame)));
308	//printf("execCtx=0x%lx\n", (uint64_t)execCtx);
309	const vmint polyIntSize = parserCtx->polyphonicIntVarCount;
310	execCtx->polyphonicIntMemory.resize(polyIntSize);
311	memset(&execCtx->polyphonicIntMemory[0], 0, polyIntSize * sizeof(vmint));
312
313	const vmint polyRealSize = parserCtx->polyphonicRealVarCount;
314	execCtx->polyphonicRealMemory.resize(polyRealSize);
315	memset(&execCtx->polyphonicRealMemory[0], 0, polyRealSize * sizeof(vmfloat));
316
317	const vmint polyFactorSize = parserCtx->polyphonicUnitFactorCount;
318	execCtx->polyphonicUnitFactorMemory.resize(polyFactorSize);
319	for (vmint i = 0; i < polyFactorSize; ++i)
320	execCtx->polyphonicUnitFactorMemory[i] = VM_NO_FACTOR;
321
322	dmsg(2,("Allocated %lld bytes polyphonic int memory.\n", polyIntSize * sizeof(vmint)));
323	dmsg(2,("Allocated %lld bytes polyphonic real memory.\n", polyRealSize * sizeof(vmfloat)));
324	dmsg(2,("Allocated %lld bytes unit factor memory.\n", polyFactorSize * sizeof(vmfloat)));
325	return execCtx;
326	}
327
328	std::vector<VMSourceToken> ScriptVM::syntaxHighlighting(const String& s) {
329	std::istringstream iss(s);
330	return syntaxHighlighting(&iss);
331	}
332
333	std::vector<VMSourceToken> ScriptVM::syntaxHighlighting(std::istream* is) {
334	try {
335	NkspScanner scanner(is);
336	std::vector<SourceToken> tokens = scanner.tokens();
337	std::vector<VMSourceToken> result;
338	result.resize(tokens.size());
339	for (vmint i = 0; i < tokens.size(); ++i) {
340	SourceToken* st = new SourceToken;
341	*st = tokens[i];
342	result[i] = VMSourceToken(st);
343	}
344	return result;
345	} catch (...) {
346	return std::vector<VMSourceToken>();
347	}
348	}
349
350	VMFunction* ScriptVM::functionByName(const String& name) {
351	if (name == "message") return m_fnMessage;
352	else if (name == "exit") return m_fnExit;
353	else if (name == "wait") return m_fnWait;
354	else if (name == "abs") return m_fnAbs;
355	else if (name == "random") return m_fnRandom;
356	else if (name == "num_elements") return m_fnNumElements;
357	else if (name == "inc") return m_fnInc;
358	else if (name == "dec") return m_fnDec;
359	else if (name == "in_range") return m_fnInRange;
360	else if (name == "sh_left") return m_fnShLeft;
361	else if (name == "sh_right") return m_fnShRight;
362	else if (name == "msb") return m_fnMsb;
363	else if (name == "lsb") return m_fnLsb;
364	else if (name == "min") return m_fnMin;
365	else if (name == "max") return m_fnMax;
366	else if (name == "array_equal") return m_fnArrayEqual;
367	else if (name == "search") return m_fnSearch;
368	else if (name == "sort") return m_fnSort;
369	else if (name == "int_to_real") return m_fnIntToReal;
370	else if (name == "real") return m_fnIntToReal;
371	else if (name == "real_to_int") return m_fnRealToInt;
372	else if (name == "int") return m_fnRealToInt;
373	else if (name == "round") return m_fnRound;
374	else if (name == "ceil") return m_fnCeil;
375	else if (name == "floor") return m_fnFloor;
376	else if (name == "sqrt") return m_fnSqrt;
377	else if (name == "log") return m_fnLog;
378	else if (name == "log2") return m_fnLog2;
379	else if (name == "log10") return m_fnLog10;
380	else if (name == "exp") return m_fnExp;
381	else if (name == "pow") return m_fnPow;
382	else if (name == "sin") return m_fnSin;
383	else if (name == "cos") return m_fnCos;
384	else if (name == "tan") return m_fnTan;
385	else if (name == "asin") return m_fnAsin;
386	else if (name == "acos") return m_fnAcos;
387	else if (name == "atan") return m_fnAtan;
388	return NULL;
389	}
390
391	bool ScriptVM::isFunctionDisabled(VMFunction* fn, VMParserContext* ctx) {
392	ParserContext* parserCtx = dynamic_cast<ParserContext*>(ctx);
393	if (!parserCtx) return false;
394
395	if (fn == m_fnMessage && parserCtx->userPreprocessorConditions.count("NKSP_NO_MESSAGE"))
396	return true;
397
398	return false;
399	}
400
401	std::map<String,VMIntPtr*> ScriptVM::builtInIntVariables() {
402	return std::map<String,VMIntPtr*>();
403	}
404
405	std::map<String,VMInt8Array*> ScriptVM::builtInIntArrayVariables() {
406	return std::map<String,VMInt8Array*>();
407	}
408
409	std::map<String,VMDynVar*> ScriptVM::builtInDynamicVariables() {
410	std::map<String,VMDynVar*> m;
411
412	m["$NKSP_PERF_TIMER"] = m_varPerfTimer;
413	m["$NKSP_REAL_TIMER"] = m_varRealTimer;
414	m["$KSP_TIMER"] = m_varRealTimer;
415
416	return m;
417	}
418
419	std::map<String,vmint> ScriptVM::builtInConstIntVariables() {
420	std::map<String,vmint> m;
421
422	m["$NI_CB_TYPE_INIT"] = VM_EVENT_HANDLER_INIT;
423	m["$NI_CB_TYPE_NOTE"] = VM_EVENT_HANDLER_NOTE;
424	m["$NI_CB_TYPE_RELEASE"] = VM_EVENT_HANDLER_RELEASE;
425	m["$NI_CB_TYPE_CONTROLLER"] = VM_EVENT_HANDLER_CONTROLLER;
426	m["$NI_CB_TYPE_RPN"] = VM_EVENT_HANDLER_RPN;
427	m["$NI_CB_TYPE_NRPN"] = VM_EVENT_HANDLER_NRPN;
428
429	return m;
430	}
431
432	std::map<String,vmfloat> ScriptVM::builtInConstRealVariables() {
433	std::map<String,vmfloat> m;
434
435	m["~NI_MATH_PI"] = M_PI;
436	m["~NI_MATH_E"] = M_E;
437
438	return m;
439	}
440
441	VMEventHandler* ScriptVM::currentVMEventHandler() {
442	return m_eventHandler;
443	}
444
445	VMParserContext* ScriptVM::currentVMParserContext() {
446	return m_parserContext;
447	}
448
449	VMExecContext* ScriptVM::currentVMExecContext() {
450	if (!m_parserContext) return NULL;
451	return m_parserContext->execContext;
452	}
453
454	void ScriptVM::setAutoSuspendEnabled(bool b) {
455	m_autoSuspend = b;
456	}
457
458	bool ScriptVM::isAutoSuspendEnabled() const {
459	return m_autoSuspend;
460	}
461
462	void ScriptVM::setExitResultEnabled(bool b) {
463	m_acceptExitRes = b;
464	}
465
466	bool ScriptVM::isExitResultEnabled() const {
467	return m_acceptExitRes;
468	}
469
470	VMExecStatus_t ScriptVM::exec(VMParserContext* parserContext, VMExecContext* execContex, VMEventHandler* handler) {
471	m_parserContext = dynamic_cast<ParserContext*>(parserContext);
472	if (!m_parserContext) {
473	std::cerr << "No VM parser context provided. Did you load a script?\n";
474	return VMExecStatus_t(VM_EXEC_NOT_RUNNING \| VM_EXEC_ERROR);
475	}
476
477	// a ParserContext object is always tied to exactly one ScriptVM object
478	assert(m_parserContext->functionProvider == this);
479
480	ExecContext* ctx = dynamic_cast<ExecContext*>(execContex);
481	if (!ctx) {
482	std::cerr << "Invalid VM exec context.\n";
483	return VMExecStatus_t(VM_EXEC_NOT_RUNNING \| VM_EXEC_ERROR);
484	}
485	EventHandler* h = dynamic_cast<EventHandler*>(handler);
486	if (!h) return VM_EXEC_NOT_RUNNING;
487	m_eventHandler = handler;
488
489	m_parserContext->execContext = ctx;
490
491	ctx->status = VM_EXEC_RUNNING;
492	ctx->instructionsCount = 0;
493	ctx->clearExitRes();
494	StmtFlags_t& flags = ctx->flags;
495	vmint instructionsCounter = 0;
496	vmint synced = m_autoSuspend ? 0 : 1;
497
498	int& frameIdx = ctx->stackFrame;
499	if (frameIdx < 0) { // start condition ...
500	frameIdx = -1;
501	ctx->pushStack(h);
502	}
503
504	while (flags == STMT_SUCCESS && frameIdx >= 0) {
505	if (frameIdx >= ctx->stack.size()) { // should never happen, otherwise it's a bug ...
506	std::cerr << "CRITICAL: VM stack overflow! (" << frameIdx << ")\n";
507	flags = StmtFlags_t(STMT_ABORT_SIGNALLED \| STMT_ERROR_OCCURRED);
508	break;
509	}
510
511	ExecContext::StackFrame& frame = ctx->stack[frameIdx];
512	switch (frame.statement->statementType()) {
513	case STMT_LEAF: {
514	#if DEBUG_SCRIPTVM_CORE
515	_printIndents(frameIdx);
516	printf("-> STMT_LEAF\n");
517	#endif
518	LeafStatement* leaf = (LeafStatement*) frame.statement;
519	flags = leaf->exec();
520	ctx->popStack();
521	break;
522	}
523
524	case STMT_LIST: {
525	#if DEBUG_SCRIPTVM_CORE
526	_printIndents(frameIdx);
527	printf("-> STMT_LIST subidx=%d\n", frame.subindex);
528	#endif
529	Statements* stmts = (Statements*) frame.statement;
530	if (stmts->statement(frame.subindex)) {
531	ctx->pushStack(
532	stmts->statement(frame.subindex++)
533	);
534	} else {
535	#if DEBUG_SCRIPTVM_CORE
536	_printIndents(frameIdx);
537	printf("[END OF LIST] subidx=%d\n", frame.subindex);
538	#endif
539	ctx->popStack();
540	}
541	break;
542	}
543
544	case STMT_BRANCH: {
545	#if DEBUG_SCRIPTVM_CORE
546	_printIndents(frameIdx);
547	printf("-> STMT_BRANCH\n");
548	#endif
549	if (frame.subindex < 0) ctx->popStack();
550	else {
551	BranchStatement* branchStmt = (BranchStatement*) frame.statement;
552	frame.subindex =
553	(decltype(frame.subindex))
554	branchStmt->evalBranch();
555	if (frame.subindex >= 0) {
556	ctx->pushStack(
557	branchStmt->branch(frame.subindex)
558	);
559	frame.subindex = -1;
560	} else ctx->popStack();
561	}
562	break;
563	}
564
565	case STMT_LOOP: {
566	#if DEBUG_SCRIPTVM_CORE
567	_printIndents(frameIdx);
568	printf("-> STMT_LOOP\n");
569	#endif
570	While* whileStmt = (While*) frame.statement;
571	if (whileStmt->evalLoopStartCondition() && whileStmt->statements()) {
572	ctx->pushStack(
573	whileStmt->statements()
574	);
575	if (flags == STMT_SUCCESS && !synced &&
576	instructionsCounter > SCRIPTVM_MAX_INSTR_PER_CYCLE_SOFT)
577	{
578	flags = StmtFlags_t(STMT_SUSPEND_SIGNALLED);
579	ctx->suspendMicroseconds = SCRIPT_VM_FORCE_SUSPENSION_MICROSECONDS;
580	}
581	} else ctx->popStack();
582	break;
583	}
584
585	case STMT_SYNC: {
586	#if DEBUG_SCRIPTVM_CORE
587	_printIndents(frameIdx);
588	printf("-> STMT_SYNC\n");
589	#endif
590	SyncBlock* syncStmt = (SyncBlock*) frame.statement;
591	if (!frame.subindex++ && syncStmt->statements()) {
592	++synced;
593	ctx->pushStack(
594	syncStmt->statements()
595	);
596	} else {
597	ctx->popStack();
598	--synced;
599	}
600	break;
601	}
602
603	case STMT_NOOP:
604	break; // no operation like the name suggests
605	}
606
607	if (flags == STMT_SUCCESS && !synced &&
608	instructionsCounter > SCRIPTVM_MAX_INSTR_PER_CYCLE_HARD)
609	{
610	flags = StmtFlags_t(STMT_SUSPEND_SIGNALLED);
611	ctx->suspendMicroseconds = SCRIPT_VM_FORCE_SUSPENSION_MICROSECONDS;
612	}
613
614	++instructionsCounter;
615	}
616
617	if ((flags & STMT_SUSPEND_SIGNALLED) && !(flags & STMT_ABORT_SIGNALLED)) {
618	ctx->status = VM_EXEC_SUSPENDED;
619	ctx->flags = STMT_SUCCESS;
620	} else {
621	ctx->status = VM_EXEC_NOT_RUNNING;
622	if (flags & STMT_ERROR_OCCURRED)
623	ctx->status = VM_EXEC_ERROR;
624	ctx->reset();
625	}
626
627	ctx->instructionsCount = instructionsCounter;
628
629	m_eventHandler = NULL;
630	m_parserContext->execContext = NULL;
631	m_parserContext = NULL;
632	return ctx->status;
633	}
634
635	} // namespace LinuxSampler