src/scriptvm/ScriptVM.cpp

/*
 * Copyright (c) 2014 - 2016 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 "editor/NkspScanner.h"

#define DEBUG_SCRIPTVM_CORE 0

int InstrScript_parse(LinuxSampler::ParserContext*);

namespace LinuxSampler {

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

    static int _requiredMaxStackSizeFor(Statement* statement, int 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;
                int max = 0;
                for (int i = 0; stmts->statement(i); ++i) {
                    int 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;
                int max = 0;
                for (int i = 0; branchStmt->branch(i); ++i) {
                    int 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;
            }
        }

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

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

    ScriptVM::ScriptVM() : m_eventHandler(NULL), m_parserContext(NULL) {
        m_fnMessage = new CoreVMFunction_message;
        m_fnExit = new CoreVMFunction_exit;
        m_fnWait = new CoreVMFunction_wait(this);
        m_fnAbs = new CoreVMFunction_abs;
        m_fnRandom = new CoreVMFunction_random;
        m_fnNumElements = new CoreVMFunction_num_elements;
    }

    ScriptVM::~ScriptVM() {
        delete m_fnMessage;
        delete m_fnExit;
        delete m_fnWait;
        delete m_fnAbs;
        delete m_fnRandom;
        delete m_fnNumElements;
    }

    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->registerBuiltInIntVariables( builtInIntVariables() );
        context->registerBuiltInIntArrayVariables( builtInIntArrayVariables() );

        context->createScanner(is);

        InstrScript_parse(context);
        dmsg(2,("Allocating %ld bytes of global int VM memory.\n", long(context->globalIntVarCount * sizeof(int))));
        dmsg(2,("Allocating %d of global VM string variables.\n", context->globalStrVarCount));
        if (!context->globalIntMemory)
            context->globalIntMemory = new ArrayList<int>();
        if (!context->globalStrMemory)
            context->globalStrMemory = new ArrayList<String>();
        context->globalIntMemory->resize(context->globalIntVarCount);
        memset(&((*context->globalIntMemory)[0]), 0, context->globalIntVarCount * sizeof(int));
        
        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 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 %ld bytes VM stack size.\n",
                long(parserCtx->requiredMaxStackSize * sizeof(ExecContext::StackFrame))));
        //printf("execCtx=0x%lx\n", (uint64_t)execCtx);
        const int polySize = parserCtx->polyphonicIntVarCount;
        execCtx->polyphonicIntMemory.resize(polySize);
        memset(&execCtx->polyphonicIntMemory[0], 0, polySize * sizeof(int));

        dmsg(2,("Allocated %ld bytes polyphonic memory.\n", long(polySize * sizeof(int))));
        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) {
        NkspScanner scanner(is);
        std::vector<SourceToken> tokens = scanner.tokens();
        std::vector<VMSourceToken> result;
        result.resize(tokens.size());
        for (int i = 0; i < tokens.size(); ++i) {
            SourceToken* st = new SourceToken;
            *st = tokens[i];
            result[i] = VMSourceToken(st);
        }
        return result;
    }

    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;
        return NULL;
    }

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

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

    std::map<String,int> ScriptVM::builtInConstIntVariables() {
        return std::map<String,int>();
    }

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

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

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

    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;
        StmtFlags_t flags = STMT_SUCCESS;

        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 = 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()
                        );
                    } else ctx->popStack();
                }
            }
        }

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

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

} // namespace LinuxSampler
1	schoenebeck	2581	/*
2	schoenebeck	2879	* Copyright (c) 2014 - 2016 Christian Schoenebeck
3	schoenebeck	2581	*
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	schoenebeck	2588	#include <string.h>
13	schoenebeck	2619	#include <assert.h>
14	schoenebeck	2581	#include "../common/global_private.h"
15			#include "tree.h"
16	schoenebeck	2885	#include "CoreVMFunctions.h"
17			#include "editor/NkspScanner.h"
18	schoenebeck	2581
19			#define DEBUG_SCRIPTVM_CORE 0
20
21			int InstrScript_parse(LinuxSampler::ParserContext*);
22
23			namespace LinuxSampler {
24
25			static void _printIndents(int n) {
26			for (int i = 0; i < n; ++i) printf(" ");
27			fflush(stdout);
28			}
29
30			static int _requiredMaxStackSizeFor(Statement* statement, int depth = 0) {
31			if (!statement) return 1;
32
33			switch (statement->statementType()) {
34			case STMT_LEAF:
35			#if DEBUG_SCRIPTVM_CORE
36			_printIndents(depth);
37			printf("-> STMT_LEAF\n");
38			#endif
39			return 1;
40
41			case STMT_LIST: {
42			#if DEBUG_SCRIPTVM_CORE
43			_printIndents(depth);
44			printf("-> STMT_LIST\n");
45			#endif
46			Statements* stmts = (Statements*) statement;
47			int max = 0;
48			for (int i = 0; stmts->statement(i); ++i) {
49			int size = _requiredMaxStackSizeFor( stmts->statement(i), depth+1 );
50			if (max < size) max = size;
51			}
52			return max + 1;
53			}
54
55			case STMT_BRANCH: {
56			#if DEBUG_SCRIPTVM_CORE
57			_printIndents(depth);
58			printf("-> STMT_BRANCH\n");
59			#endif
60			BranchStatement* branchStmt = (BranchStatement*) statement;
61			int max = 0;
62			for (int i = 0; branchStmt->branch(i); ++i) {
63			int size = _requiredMaxStackSizeFor( branchStmt->branch(i), depth+1 );
64			if (max < size) max = size;
65			}
66			return max + 1;
67			}
68
69			case STMT_LOOP: {
70			#if DEBUG_SCRIPTVM_CORE
71			_printIndents(depth);
72			printf("-> STMT_LOOP\n");
73			#endif
74			While* whileStmt = (While*) statement;
75			if (whileStmt->statements())
76			return _requiredMaxStackSizeFor( whileStmt->statements() ) + 1;
77			else
78			return 1;
79			}
80			}
81
82			return 1; // actually just to avoid compiler warning
83			}
84
85			static int _requiredMaxStackSizeFor(EventHandlers* handlers) {
86			int max = 1;
87			for (int i = 0; i < handlers->size(); ++i) {
88			int size = _requiredMaxStackSizeFor(handlers->eventHandler(i));
89			if (max < size) max = size;
90			}
91			return max;
92			}
93
94	schoenebeck	2885	ScriptVM::ScriptVM() : m_eventHandler(NULL), m_parserContext(NULL) {
95			m_fnMessage = new CoreVMFunction_message;
96			m_fnExit = new CoreVMFunction_exit;
97			m_fnWait = new CoreVMFunction_wait(this);
98			m_fnAbs = new CoreVMFunction_abs;
99			m_fnRandom = new CoreVMFunction_random;
100			m_fnNumElements = new CoreVMFunction_num_elements;
101	schoenebeck	2581	}
102
103			ScriptVM::~ScriptVM() {
104	schoenebeck	2885	delete m_fnMessage;
105			delete m_fnExit;
106			delete m_fnWait;
107			delete m_fnAbs;
108			delete m_fnRandom;
109			delete m_fnNumElements;
110	schoenebeck	2581	}
111
112	schoenebeck	2588	VMParserContext* ScriptVM::loadScript(const String& s) {
113	schoenebeck	2581	std::istringstream iss(s);
114	schoenebeck	2588	return loadScript(&iss);
115	schoenebeck	2581	}
116
117	schoenebeck	2588	VMParserContext* ScriptVM::loadScript(std::istream* is) {
118			ParserContext* context = new ParserContext(this);
119			//printf("parserCtx=0x%lx\n", (uint64_t)context);
120	schoenebeck	2594
121			context->registerBuiltInConstIntVariables( builtInConstIntVariables() );
122			context->registerBuiltInIntVariables( builtInIntVariables() );
123			context->registerBuiltInIntArrayVariables( builtInIntArrayVariables() );
124
125	schoenebeck	2588	context->createScanner(is);
126	schoenebeck	2581
127	schoenebeck	2588	InstrScript_parse(context);
128	persson	2837	dmsg(2,("Allocating %ld bytes of global int VM memory.\n", long(context->globalIntVarCount * sizeof(int))));
129	schoenebeck	2611	dmsg(2,("Allocating %d of global VM string variables.\n", context->globalStrVarCount));
130	schoenebeck	2588	if (!context->globalIntMemory)
131			context->globalIntMemory = new ArrayList<int>();
132			if (!context->globalStrMemory)
133			context->globalStrMemory = new ArrayList<String>();
134			context->globalIntMemory->resize(context->globalIntVarCount);
135			memset(&((context->globalIntMemory)[0]), 0, context->globalIntVarCount sizeof(int));
136
137			context->globalStrMemory->resize(context->globalStrVarCount);
138	schoenebeck	2581
139	schoenebeck	2588	context->destroyScanner();
140	schoenebeck	2581
141	schoenebeck	2588	return context;
142	schoenebeck	2581	}
143
144	schoenebeck	2588	void ScriptVM::dumpParsedScript(VMParserContext* context) {
145			ParserContext* ctx = dynamic_cast<ParserContext*>(context);
146			if (!ctx) {
147	schoenebeck	2581	std::cerr << "No VM context. So nothing to dump.\n";
148			return;
149			}
150	schoenebeck	2588	if (!ctx->handlers) {
151	schoenebeck	2581	std::cerr << "No event handlers defined in script. So nothing to dump.\n";
152			return;
153			}
154	schoenebeck	2588	if (!ctx->globalIntMemory) {
155	schoenebeck	2581	std::cerr << "Internal error: no global memory assigend to script VM.\n";
156			return;
157			}
158	schoenebeck	2588	ctx->handlers->dump();
159	schoenebeck	2581	}
160
161	schoenebeck	2588	VMExecContext* ScriptVM::createExecContext(VMParserContext* parserContext) {
162			ParserContext* parserCtx = dynamic_cast<ParserContext*>(parserContext);
163			ExecContext* execCtx = new ExecContext();
164
165			if (parserCtx->requiredMaxStackSize < 0) {
166			parserCtx->requiredMaxStackSize =
167			_requiredMaxStackSizeFor(&*parserCtx->handlers);
168			}
169			execCtx->stack.resize(parserCtx->requiredMaxStackSize);
170	persson	2837	dmsg(2,("Created VM exec context with %ld bytes VM stack size.\n",
171			long(parserCtx->requiredMaxStackSize * sizeof(ExecContext::StackFrame))));
172	schoenebeck	2588	//printf("execCtx=0x%lx\n", (uint64_t)execCtx);
173			const int polySize = parserCtx->polyphonicIntVarCount;
174			execCtx->polyphonicIntMemory.resize(polySize);
175			memset(&execCtx->polyphonicIntMemory[0], 0, polySize * sizeof(int));
176
177	persson	2837	dmsg(2,("Allocated %ld bytes polyphonic memory.\n", long(polySize * sizeof(int))));
178	schoenebeck	2588	return execCtx;
179	schoenebeck	2581	}
180
181	schoenebeck	2885	std::vector<VMSourceToken> ScriptVM::syntaxHighlighting(const String& s) {
182			std::istringstream iss(s);
183			return syntaxHighlighting(&iss);
184			}
185
186			std::vector<VMSourceToken> ScriptVM::syntaxHighlighting(std::istream* is) {
187			NkspScanner scanner(is);
188			std::vector<SourceToken> tokens = scanner.tokens();
189			std::vector<VMSourceToken> result;
190			result.resize(tokens.size());
191			for (int i = 0; i < tokens.size(); ++i) {
192			SourceToken* st = new SourceToken;
193			*st = tokens[i];
194			result[i] = VMSourceToken(st);
195			}
196			return result;
197			}
198
199	schoenebeck	2581	VMFunction* ScriptVM::functionByName(const String& name) {
200	schoenebeck	2885	if (name == "message") return m_fnMessage;
201			else if (name == "exit") return m_fnExit;
202			else if (name == "wait") return m_fnWait;
203			else if (name == "abs") return m_fnAbs;
204			else if (name == "random") return m_fnRandom;
205			else if (name == "num_elements") return m_fnNumElements;
206	schoenebeck	2581	return NULL;
207			}
208	schoenebeck	2588
209	schoenebeck	2594	std::map<String,VMIntRelPtr*> ScriptVM::builtInIntVariables() {
210			return std::map<String,VMIntRelPtr*>();
211			}
212
213			std::map<String,VMInt8Array*> ScriptVM::builtInIntArrayVariables() {
214			return std::map<String,VMInt8Array*>();
215			}
216
217			std::map<String,int> ScriptVM::builtInConstIntVariables() {
218			return std::map<String,int>();
219			}
220
221	schoenebeck	2879	VMEventHandler* ScriptVM::currentVMEventHandler() {
222			return m_eventHandler;
223			}
224
225	schoenebeck	2588	VMParserContext* ScriptVM::currentVMParserContext() {
226			return m_parserContext;
227			}
228
229	schoenebeck	2581	VMExecContext* ScriptVM::currentVMExecContext() {
230	schoenebeck	2588	if (!m_parserContext) return NULL;
231			return m_parserContext->execContext;
232	schoenebeck	2581	}
233
234	schoenebeck	2588	VMExecStatus_t ScriptVM::exec(VMParserContext* parserContext, VMExecContext* execContex, VMEventHandler* handler) {
235			m_parserContext = dynamic_cast<ParserContext*>(parserContext);
236			if (!m_parserContext) {
237			std::cerr << "No VM parser context provided. Did you load a script?.\n";
238	schoenebeck	2581	return VMExecStatus_t(VM_EXEC_NOT_RUNNING \| VM_EXEC_ERROR);
239			}
240
241	schoenebeck	2611	// a ParserContext object is always tied to exactly one ScriptVM object
242			assert(m_parserContext->functionProvider == this);
243
244	schoenebeck	2581	ExecContext* ctx = dynamic_cast<ExecContext*>(execContex);
245			if (!ctx) {
246			std::cerr << "Invalid VM exec context.\n";
247			return VMExecStatus_t(VM_EXEC_NOT_RUNNING \| VM_EXEC_ERROR);
248			}
249			EventHandler* h = dynamic_cast<EventHandler*>(handler);
250			if (!h) return VM_EXEC_NOT_RUNNING;
251	schoenebeck	2879	m_eventHandler = handler;
252	schoenebeck	2581
253	schoenebeck	2588	m_parserContext->execContext = ctx;
254	schoenebeck	2581
255			ctx->status = VM_EXEC_RUNNING;
256			StmtFlags_t flags = STMT_SUCCESS;
257
258			int& frameIdx = ctx->stackFrame;
259			if (frameIdx < 0) { // start condition ...
260			frameIdx = -1;
261			ctx->pushStack(h);
262			}
263
264			while (flags == STMT_SUCCESS && frameIdx >= 0) {
265			if (frameIdx >= ctx->stack.size()) { // should never happen, otherwise it's a bug ...
266			std::cerr << "CRITICAL: VM stack overflow! (" << frameIdx << ")\n";
267			flags = StmtFlags_t(STMT_ABORT_SIGNALLED \| STMT_ERROR_OCCURRED);
268			break;
269			}
270
271			ExecContext::StackFrame& frame = ctx->stack[frameIdx];
272			switch (frame.statement->statementType()) {
273			case STMT_LEAF: {
274			#if DEBUG_SCRIPTVM_CORE
275			_printIndents(frameIdx);
276			printf("-> STMT_LEAF\n");
277			#endif
278			LeafStatement* leaf = (LeafStatement*) frame.statement;
279			flags = leaf->exec();
280			ctx->popStack();
281			break;
282			}
283
284			case STMT_LIST: {
285			#if DEBUG_SCRIPTVM_CORE
286			_printIndents(frameIdx);
287			printf("-> STMT_LIST subidx=%d\n", frame.subindex);
288			#endif
289			Statements* stmts = (Statements*) frame.statement;
290			if (stmts->statement(frame.subindex)) {
291			ctx->pushStack(
292			stmts->statement(frame.subindex++)
293			);
294			} else {
295			#if DEBUG_SCRIPTVM_CORE
296			_printIndents(frameIdx);
297			printf("[END OF LIST] subidx=%d\n", frame.subindex);
298			#endif
299			ctx->popStack();
300			}
301			break;
302			}
303
304			case STMT_BRANCH: {
305			#if DEBUG_SCRIPTVM_CORE
306			_printIndents(frameIdx);
307			printf("-> STMT_BRANCH\n");
308			#endif
309			if (frame.subindex < 0) ctx->popStack();
310			else {
311			BranchStatement* branchStmt = (BranchStatement*) frame.statement;
312			frame.subindex = branchStmt->evalBranch();
313			if (frame.subindex >= 0) {
314			ctx->pushStack(
315			branchStmt->branch(frame.subindex)
316			);
317			frame.subindex = -1;
318			} else ctx->popStack();
319			}
320			break;
321			}
322
323			case STMT_LOOP: {
324			#if DEBUG_SCRIPTVM_CORE
325			_printIndents(frameIdx);
326			printf("-> STMT_LOOP\n");
327			#endif
328			While* whileStmt = (While*) frame.statement;
329			if (whileStmt->evalLoopStartCondition() && whileStmt->statements()) {
330			ctx->pushStack(
331			whileStmt->statements()
332			);
333			} else ctx->popStack();
334			}
335			}
336			}
337
338			if (flags & STMT_SUSPEND_SIGNALLED) {
339			ctx->status = VM_EXEC_SUSPENDED;
340			} else {
341			ctx->status = VM_EXEC_NOT_RUNNING;
342			if (flags & STMT_ERROR_OCCURRED)
343			ctx->status = VM_EXEC_ERROR;
344			ctx->reset();
345			}
346
347	schoenebeck	2879	m_eventHandler = NULL;
348	schoenebeck	2588	m_parserContext->execContext = NULL;
349			m_parserContext = NULL;
350	schoenebeck	2581	return ctx->status;
351			}
352
353			} // namespace LinuxSampler