Tcl Source Code

typedef struct TEBCdata {
    ByteCode *codePtr;		/* Constant until the BC returns */
				/* -----------------------------------------*/
    const unsigned char *pc;	/* These fields are used on return TO this */
    ptrdiff_t *catchTop;	/* this level: they record the state when a */
    int cleanup;		/* new codePtr was received for NR */
    Tcl_Obj *auxObjList;	/* execution. */
    int checkInterp;
    CmdFrame cmdFrame;
    void *stack[1];		/* Start of the actual combined catch and obj
				 * stacks; the struct will be expanded as
				 * necessary */
} TEBCdata;

#define TEBC_YIELD() \

    esPtr->tosPtr = initTosPtr;

    TD->codePtr     = codePtr;
    TD->pc	    = codePtr->codeStart;
    TD->catchTop    = initCatchTop;
    TD->cleanup     = 0;
    TD->auxObjList  = NULL;
    TD->checkInterp = 0;

    /*
     * TIP #280: Initialize the frame. Do not push it yet: it will be pushed
     * every time that we call out from this TD, popped when we return to it.
     */

    bcFramePtr->type = ((codePtr->flags & TCL_BYTECODE_PRECOMPILED)

     * used too frequently
     */

    TEBCdata *TD = data[0];
#define auxObjList	(TD->auxObjList)
#define catchTop	(TD->catchTop)
#define codePtr		(TD->codePtr)
#define checkInterp	(TD->checkInterp)
			/* Indicates when a check of interp readyness is
			 * necessary. Set by CACHE_STACK_INFO() */

    /*
     * Globals: variables that store state, must remain valid at all times.
     */

    Tcl_Obj **tosPtr;		/* Cached pointer to top of evaluation
				 * stack. */
    const unsigned char *pc;	/* The current program counter. */
    unsigned char inst;         /* The currently running instruction */
    
    /*
     * Transfer variables - needed only between opcodes, but not while
     * executing an instruction.
     */

    int cleanup = 0;
    Tcl_Obj *objResultPtr;



    /*
     * Locals - variables that are used within opcodes or bounded sections of
     * the file (jumps between opcodes within a family).
     * NOTE: These are now mostly defined locally where needed.
     */

    if (!data[1] && (tclTraceExec >= 2)) {
	PrintByteCodeInfo(codePtr);
	fprintf(stdout, "  Starting stack top=%d\n", (int) CURR_DEPTH);
	fflush(stdout);
    }
#endif






    if (data[1] /* resume from invocation */) {

	if (iPtr->execEnvPtr->rewind) {
	    result = TCL_ERROR;

	}

	NRE_ASSERT(iPtr->cmdFramePtr == bcFramePtr);
	if (bcFramePtr->cmdObj) {
	    Tcl_DecrRefCount(bcFramePtr->cmdObj);
	    bcFramePtr->cmdObj = NULL;
	    bcFramePtr->cmd = NULL;
	}
	iPtr->cmdFramePtr = bcFramePtr->nextPtr;
	if (iPtr->flags & INTERP_DEBUG_FRAME) {
	    TclArgumentBCRelease((Tcl_Interp *) iPtr, bcFramePtr);
	}
	if (codePtr->flags & TCL_BYTECODE_RECOMPILE) {
	    iPtr->flags |= ERR_ALREADY_LOGGED;
	    codePtr->flags &= ~TCL_BYTECODE_RECOMPILE;
	}

	CACHE_STACK_INFO();
	if (result == TCL_OK) {
	    /*
	     * Push the call's object result and continue execution with the
	     * next instruction.
	     */

	    TRACE_WITH_OBJ(("%u => ... after \"%.20s\": TCL_OK, result=",

#ifndef TCL_COMPILE_DEBUG
	    if (*pc == INST_POP) {
		TclDecrRefCount(objResultPtr);
		NEXT_INST_V(1, cleanup, 0);
	    }
#endif
	    NEXT_INST_V(0, cleanup, -1);
	}

	/*
	 * Result not TCL_OK: fall through
	 */
    }

    if (iPtr->execEnvPtr->rewind) {
	result = TCL_ERROR;
	goto abnormalReturn;
    }

    if (result != TCL_OK) {
	pc--;
	goto processExceptionReturn;
    }

    /*
     * Loop executing instructions until a "done" instruction, a TCL_RETURN,
     * or some error.
     */

    goto cleanup0;

    /*
     * Targets for standard instruction endings; unrolled for speed in the
     * most frequent cases (instructions that consume up to two stack
     * elements).
     *
     * This used to be a "for(;;)" loop, with each instruction doing its own