Tcl Source Code

Artifact [eb251b0543]
Login

Artifact eb251b0543e6b6562a6ae6bd36c5e6bb7f369810:


/* 
 * tclExecute.c --
 *
 *	This file contains procedures that execute byte-compiled Tcl
 *	commands.
 *
 * Copyright (c) 1996-1997 Sun Microsystems, Inc.
 * Copyright (c) 1998-2000 by Scriptics Corporation.
 * Copyright (c) 2001 by Kevin B. Kenny.  All rights reserved.
 *
 * See the file "license.terms" for information on usage and redistribution
 * of this file, and for a DISCLAIMER OF ALL WARRANTIES.
 *
 * RCS: @(#) $Id: tclExecute.c,v 1.94.2.7 2004/07/03 22:13:10 msofer Exp $
 */

#include "tclInt.h"
#include "tclCompile.h"

#ifndef TCL_NO_MATH
#   include "tclMath.h"
#endif

/*
 * The stuff below is a bit of a hack so that this file can be used
 * in environments that include no UNIX, i.e. no errno.  Just define
 * errno here.
 */

#ifndef TCL_GENERIC_ONLY
#   include "tclPort.h"
#else /* TCL_GENERIC_ONLY */
#   ifndef NO_FLOAT_H
#	include <float.h>
#   else /* NO_FLOAT_H */
#	ifndef NO_VALUES_H
#	    include <values.h>
#	endif /* !NO_VALUES_H */
#   endif /* !NO_FLOAT_H */
#   define NO_ERRNO_H
#endif /* !TCL_GENERIC_ONLY */

#ifdef NO_ERRNO_H
int errno;
#   define EDOM   33
#   define ERANGE 34
#endif

/*
 * Need DBL_MAX for IS_INF() macro...
 */
#ifndef DBL_MAX
#   ifdef MAXDOUBLE
#	define DBL_MAX MAXDOUBLE
#   else /* !MAXDOUBLE */
/*
 * This value is from the Solaris headers, but doubles seem to be the
 * same size everywhere.  Long doubles aren't, but we don't use those.
 */
#	define DBL_MAX 1.79769313486231570e+308
#   endif /* MAXDOUBLE */
#endif /* !DBL_MAX */

/*
 * Boolean flag indicating whether the Tcl bytecode interpreter has been
 * initialized.
 */

static int execInitialized = 0;
TCL_DECLARE_MUTEX(execMutex)

#ifdef TCL_COMPILE_DEBUG
/*
 * Variable that controls whether execution tracing is enabled and, if so,
 * what level of tracing is desired:
 *    0: no execution tracing
 *    1: trace invocations of Tcl procs only
 *    2: trace invocations of all (not compiled away) commands
 *    3: display each instruction executed
 * This variable is linked to the Tcl variable "tcl_traceExec".
 */

int tclTraceExec = 0;
#endif

/*
 * Mapping from expression instruction opcodes to strings; used for error
 * messages. Note that these entries must match the order and number of the
 * expression opcodes (e.g., INST_LOR) in tclCompile.h.
 */

static char *operatorStrings[] = {
    "||", "&&", "|", "^", "&", "==", "!=", "<", ">", "<=", ">=", "<<", ">>",
    "+", "-", "*", "/", "%", "+", "-", "~", "!",
    "BUILTIN FUNCTION", "FUNCTION",
    "", "", "", "", "", "", "", "", "eq", "ne",
};

/*
 * Mapping from Tcl result codes to strings; used for error and debugging
 * messages. 
 */

#ifdef TCL_COMPILE_DEBUG
static char *resultStrings[] = {
    "TCL_OK", "TCL_ERROR", "TCL_RETURN", "TCL_BREAK", "TCL_CONTINUE"
};
#endif

/*
 * These are used by evalstats to monitor object usage in Tcl.
 */

#ifdef TCL_COMPILE_STATS
long		tclObjsAlloced = 0;
long		tclObjsFreed   = 0;
#define TCL_MAX_SHARED_OBJ_STATS 5
long		tclObjsShared[TCL_MAX_SHARED_OBJ_STATS] = { 0, 0, 0, 0, 0 };
#endif /* TCL_COMPILE_STATS */

/*
 * Macros for testing floating-point values for certain special cases. Test
 * for not-a-number by comparing a value against itself; test for infinity
 * by comparing against the largest floating-point value.
 */

#define IS_NAN(v) ((v) != (v))
#define IS_INF(v) (((v) > DBL_MAX) || ((v) < -DBL_MAX))

/*
 * The new macro for ending an instruction; note that a
 * reasonable C-optimiser will resolve all branches
 * at compile time. (result) is always a constant; the macro 
 * NEXT_INST_F handles constant (nCleanup), NEXT_INST_V is
 * resolved at runtime for variable (nCleanup).
 *
 * ARGUMENTS:
 *    pcAdjustment: how much to increment pc
 *    nCleanup: how many objects to remove from the stack
 *    result: 0 indicates no object should be pushed on the
 *       stack; otherwise, push objResultPtr. If (result < 0),
 *       objResultPtr already has the correct reference count.
 */

#define NEXT_INST_F(pcAdjustment, nCleanup, result) \
     if (nCleanup == 0) {\
	 if (result != 0) {\
	     if ((result) > 0) {\
		 PUSH_OBJECT(objResultPtr);\
	     } else {\
		 stackPtr[++stackTop] = objResultPtr;\
	     }\
	 } \
	 pc += (pcAdjustment);\
	 goto cleanup0;\
     } else if (result != 0) {\
	 if ((result) > 0) {\
	     Tcl_IncrRefCount(objResultPtr);\
	 }\
	 pc += (pcAdjustment);\
	 switch (nCleanup) {\
	     case 1: goto cleanup1_pushObjResultPtr;\
	     case 2: goto cleanup2_pushObjResultPtr;\
	     default: panic("ERROR: bad usage of macro NEXT_INST_F");\
	 }\
     } else {\
	 pc += (pcAdjustment);\
	 switch (nCleanup) {\
	     case 1: goto cleanup1;\
	     case 2: goto cleanup2;\
	     default: panic("ERROR: bad usage of macro NEXT_INST_F");\
	 }\
     }

#define NEXT_INST_V(pcAdjustment, nCleanup, result) \
    pc += (pcAdjustment);\
    cleanup = (nCleanup);\
    if (result) {\
	if ((result) > 0) {\
	    Tcl_IncrRefCount(objResultPtr);\
	}\
	goto cleanupV_pushObjResultPtr;\
    } else {\
	goto cleanupV;\
    }


/*
 * Macros used to cache often-referenced Tcl evaluation stack information
 * in local variables. Note that a DECACHE_STACK_INFO()-CACHE_STACK_INFO()
 * pair must surround any call inside TclExecuteByteCode (and a few other
 * procedures that use this scheme) that could result in a recursive call
 * to TclExecuteByteCode.
 */

#define CACHE_STACK_INFO() \
    stackPtr = eePtr->stackPtr; \
    stackTop = eePtr->stackTop

#define DECACHE_STACK_INFO() \
    eePtr->stackTop = stackTop


/*
 * Macros used to access items on the Tcl evaluation stack. PUSH_OBJECT
 * increments the object's ref count since it makes the stack have another
 * reference pointing to the object. However, POP_OBJECT does not decrement
 * the ref count. This is because the stack may hold the only reference to
 * the object, so the object would be destroyed if its ref count were
 * decremented before the caller had a chance to, e.g., store it in a
 * variable. It is the caller's responsibility to decrement the ref count
 * when it is finished with an object.
 *
 * WARNING! It is essential that objPtr only appear once in the PUSH_OBJECT
 * macro. The actual parameter might be an expression with side effects,
 * and this ensures that it will be executed only once. 
 */
    
#define PUSH_OBJECT(objPtr) \
    Tcl_IncrRefCount(stackPtr[++stackTop] = (objPtr))
    
#define POP_OBJECT() \
    (stackPtr[stackTop--])

/*
 * Macros used to trace instruction execution. The macros TRACE,
 * TRACE_WITH_OBJ, and O2S are only used inside TclExecuteByteCode.
 * O2S is only used in TRACE* calls to get a string from an object.
 */

#ifdef TCL_COMPILE_DEBUG
#   define TRACE(a) \
    if (traceInstructions) { \
        fprintf(stdout, "%2d: %2d (%u) %s ", iPtr->numLevels, stackTop, \
	       (unsigned int)(pc - codePtr->codeStart), \
	       GetOpcodeName(pc)); \
	printf a; \
    }
#   define TRACE_APPEND(a) \
    if (traceInstructions) { \
	printf a; \
    }
#   define TRACE_WITH_OBJ(a, objPtr) \
    if (traceInstructions) { \
        fprintf(stdout, "%2d: %2d (%u) %s ", iPtr->numLevels, stackTop, \
	       (unsigned int)(pc - codePtr->codeStart), \
	       GetOpcodeName(pc)); \
	printf a; \
        TclPrintObject(stdout, objPtr, 30); \
        fprintf(stdout, "\n"); \
    }
#   define O2S(objPtr) \
    (objPtr ? TclGetString(objPtr) : "")
#else /* !TCL_COMPILE_DEBUG */
#   define TRACE(a)
#   define TRACE_APPEND(a) 
#   define TRACE_WITH_OBJ(a, objPtr)
#   define O2S(objPtr)
#endif /* TCL_COMPILE_DEBUG */

/*
 * Macro to read a string containing either a wide or an int and
 * decide which it is while decoding it at the same time.  This
 * enforces the policy that integer constants between LONG_MIN and
 * LONG_MAX (inclusive) are represented by normal longs, and integer
 * constants outside that range are represented by wide ints.
 *
 * GET_WIDE_OR_INT is the same as REQUIRE_WIDE_OR_INT except it never
 * generates an error message.
 */
#define REQUIRE_WIDE_OR_INT(resultVar, objPtr, longVar, wideVar)	\
    (resultVar) = Tcl_GetWideIntFromObj(interp, (objPtr), &(wideVar));	\
    if ((resultVar) == TCL_OK && (wideVar) >= Tcl_LongAsWide(LONG_MIN)	\
	    && (wideVar) <= Tcl_LongAsWide(LONG_MAX)) {			\
	(objPtr)->typePtr = &tclIntType;				\
	(objPtr)->internalRep.longValue = (longVar)			\
		= Tcl_WideAsLong(wideVar);				\
    }
#define GET_WIDE_OR_INT(resultVar, objPtr, longVar, wideVar)		\
    (resultVar) = Tcl_GetWideIntFromObj((Tcl_Interp *) NULL, (objPtr),	\
	    &(wideVar));						\
    if ((resultVar) == TCL_OK && (wideVar) >= Tcl_LongAsWide(LONG_MIN)	\
	    && (wideVar) <= Tcl_LongAsWide(LONG_MAX)) {			\
	(objPtr)->typePtr = &tclIntType;				\
	(objPtr)->internalRep.longValue = (longVar)			\
		= Tcl_WideAsLong(wideVar);				\
    }
/*
 * Combined with REQUIRE_WIDE_OR_INT, this gets a long value from
 * an obj.
 */
#define FORCE_LONG(objPtr, longVar, wideVar)				\
    if ((objPtr)->typePtr == &tclWideIntType) {				\
	(longVar) = Tcl_WideAsLong(wideVar);				\
    }
#define IS_INTEGER_TYPE(typePtr)					\
	((typePtr) == &tclIntType || (typePtr) == &tclWideIntType)
#define IS_NUMERIC_TYPE(typePtr)					\
	(IS_INTEGER_TYPE(typePtr) || (typePtr) == &tclDoubleType)

#define W0	Tcl_LongAsWide(0)
/*
 * For tracing that uses wide values.
 */
#define LLD				"%" TCL_LL_MODIFIER "d"

#ifndef TCL_WIDE_INT_IS_LONG
/*
 * Extract a double value from a general numeric object.
 */
#define GET_DOUBLE_VALUE(doubleVar, objPtr, typePtr)			\
    if ((typePtr) == &tclIntType) {					\
	(doubleVar) = (double) (objPtr)->internalRep.longValue;		\
    } else if ((typePtr) == &tclWideIntType) {				\
	(doubleVar) = Tcl_WideAsDouble((objPtr)->internalRep.wideValue);\
    } else {								\
	(doubleVar) = (objPtr)->internalRep.doubleValue;		\
    }
#else /* TCL_WIDE_INT_IS_LONG */
#define GET_DOUBLE_VALUE(doubleVar, objPtr, typePtr)			\
    if (((typePtr) == &tclIntType) || ((typePtr) == &tclWideIntType)) { \
	(doubleVar) = (double) (objPtr)->internalRep.longValue;		\
    } else {								\
	(doubleVar) = (objPtr)->internalRep.doubleValue;		\
    }
#endif /* TCL_WIDE_INT_IS_LONG */

/*
 * Declarations for local procedures to this file:
 */

static int		TclExecuteByteCode _ANSI_ARGS_((Tcl_Interp *interp,
			    ByteCode *codePtr));
static int		ExprAbsFunc _ANSI_ARGS_((Tcl_Interp *interp,
			    ExecEnv *eePtr, ClientData clientData));
static int		ExprBinaryFunc _ANSI_ARGS_((Tcl_Interp *interp,
			    ExecEnv *eePtr, ClientData clientData));
static int		ExprCallMathFunc _ANSI_ARGS_((Tcl_Interp *interp,
			    ExecEnv *eePtr, int objc, Tcl_Obj **objv));
static int		ExprDoubleFunc _ANSI_ARGS_((Tcl_Interp *interp,
			    ExecEnv *eePtr, ClientData clientData));
static int		ExprIntFunc _ANSI_ARGS_((Tcl_Interp *interp,
			    ExecEnv *eePtr, ClientData clientData));
static int		ExprRandFunc _ANSI_ARGS_((Tcl_Interp *interp,
			    ExecEnv *eePtr, ClientData clientData));
static int		ExprRoundFunc _ANSI_ARGS_((Tcl_Interp *interp,
			    ExecEnv *eePtr, ClientData clientData));
static int		ExprSrandFunc _ANSI_ARGS_((Tcl_Interp *interp,
			    ExecEnv *eePtr, ClientData clientData));
static int		ExprUnaryFunc _ANSI_ARGS_((Tcl_Interp *interp,
			    ExecEnv *eePtr, ClientData clientData));
static int		ExprWideFunc _ANSI_ARGS_((Tcl_Interp *interp,
			    ExecEnv *eePtr, ClientData clientData));
#ifdef TCL_COMPILE_STATS
static int              EvalStatsCmd _ANSI_ARGS_((ClientData clientData,
                            Tcl_Interp *interp, int objc,
			    Tcl_Obj *CONST objv[]));
#endif /* TCL_COMPILE_STATS */
#ifdef TCL_COMPILE_DEBUG
static char *		GetOpcodeName _ANSI_ARGS_((unsigned char *pc));
#endif /* TCL_COMPILE_DEBUG */
static ExceptionRange *	GetExceptRangeForPc _ANSI_ARGS_((unsigned char *pc,
			    int catchOnly, ByteCode* codePtr));
static char *		GetSrcInfoForPc _ANSI_ARGS_((unsigned char *pc,
        		    ByteCode* codePtr, int *lengthPtr));
static void		GrowEvaluationStack _ANSI_ARGS_((ExecEnv *eePtr));
static void		IllegalExprOperandType _ANSI_ARGS_((
			    Tcl_Interp *interp, unsigned char *pc,
			    Tcl_Obj *opndPtr));
static void		InitByteCodeExecution _ANSI_ARGS_((
			    Tcl_Interp *interp));
#ifdef TCL_COMPILE_DEBUG
static void		PrintByteCodeInfo _ANSI_ARGS_((ByteCode *codePtr));
static char *		StringForResultCode _ANSI_ARGS_((int result));
static void		ValidatePcAndStackTop _ANSI_ARGS_((
			    ByteCode *codePtr, unsigned char *pc,
			    int stackTop, int stackLowerBound));
#endif /* TCL_COMPILE_DEBUG */
static int		VerifyExprObjType _ANSI_ARGS_((Tcl_Interp *interp,
			    Tcl_Obj *objPtr));

/*
 * Table describing the built-in math functions. Entries in this table are
 * indexed by the values of the INST_CALL_BUILTIN_FUNC instruction's
 * operand byte.
 */

BuiltinFunc tclBuiltinFuncTable[] = {
#ifndef TCL_NO_MATH
    {"acos", 1, {TCL_DOUBLE}, ExprUnaryFunc, (ClientData) acos},
    {"asin", 1, {TCL_DOUBLE}, ExprUnaryFunc, (ClientData) asin},
    {"atan", 1, {TCL_DOUBLE}, ExprUnaryFunc, (ClientData) atan},
    {"atan2", 2, {TCL_DOUBLE, TCL_DOUBLE}, ExprBinaryFunc, (ClientData) atan2},
    {"ceil", 1, {TCL_DOUBLE}, ExprUnaryFunc, (ClientData) ceil},
    {"cos", 1, {TCL_DOUBLE}, ExprUnaryFunc, (ClientData) cos},
    {"cosh", 1, {TCL_DOUBLE}, ExprUnaryFunc, (ClientData) cosh},
    {"exp", 1, {TCL_DOUBLE}, ExprUnaryFunc, (ClientData) exp},
    {"floor", 1, {TCL_DOUBLE}, ExprUnaryFunc, (ClientData) floor},
    {"fmod", 2, {TCL_DOUBLE, TCL_DOUBLE}, ExprBinaryFunc, (ClientData) fmod},
    {"hypot", 2, {TCL_DOUBLE, TCL_DOUBLE}, ExprBinaryFunc, (ClientData) hypot},
    {"log", 1, {TCL_DOUBLE}, ExprUnaryFunc, (ClientData) log},
    {"log10", 1, {TCL_DOUBLE}, ExprUnaryFunc, (ClientData) log10},
    {"pow", 2, {TCL_DOUBLE, TCL_DOUBLE}, ExprBinaryFunc, (ClientData) pow},
    {"sin", 1, {TCL_DOUBLE}, ExprUnaryFunc, (ClientData) sin},
    {"sinh", 1, {TCL_DOUBLE}, ExprUnaryFunc, (ClientData) sinh},
    {"sqrt", 1, {TCL_DOUBLE}, ExprUnaryFunc, (ClientData) sqrt},
    {"tan", 1, {TCL_DOUBLE}, ExprUnaryFunc, (ClientData) tan},
    {"tanh", 1, {TCL_DOUBLE}, ExprUnaryFunc, (ClientData) tanh},
#endif
    {"abs", 1, {TCL_EITHER}, ExprAbsFunc, 0},
    {"double", 1, {TCL_EITHER}, ExprDoubleFunc, 0},
    {"int", 1, {TCL_EITHER}, ExprIntFunc, 0},
    {"rand", 0, {TCL_EITHER}, ExprRandFunc, 0},	/* NOTE: rand takes no args. */
    {"round", 1, {TCL_EITHER}, ExprRoundFunc, 0},
    {"srand", 1, {TCL_INT}, ExprSrandFunc, 0},
    {"wide", 1, {TCL_EITHER}, ExprWideFunc, 0},
    {0},
};

/*
 *----------------------------------------------------------------------
 *
 * InitByteCodeExecution --
 *
 *	This procedure is called once to initialize the Tcl bytecode
 *	interpreter.
 *
 * Results:
 *	None.
 *
 * Side effects:
 *	This procedure initializes the array of instruction names. If
 *	compiling with the TCL_COMPILE_STATS flag, it initializes the
 *	array that counts the executions of each instruction and it
 *	creates the "evalstats" command. It also establishes the link 
 *      between the Tcl "tcl_traceExec" and C "tclTraceExec" variables.
 *
 *----------------------------------------------------------------------
 */

static void
InitByteCodeExecution(interp)
    Tcl_Interp *interp;		/* Interpreter for which the Tcl variable
				 * "tcl_traceExec" is linked to control
				 * instruction tracing. */
{
#ifdef TCL_COMPILE_DEBUG
    if (Tcl_LinkVar(interp, "tcl_traceExec", (char *) &tclTraceExec,
		    TCL_LINK_INT) != TCL_OK) {
	panic("InitByteCodeExecution: can't create link for tcl_traceExec variable");
    }
#endif
#ifdef TCL_COMPILE_STATS    
    Tcl_CreateObjCommand(interp, "evalstats", EvalStatsCmd,
	    (ClientData) NULL, (Tcl_CmdDeleteProc *) NULL);
#endif /* TCL_COMPILE_STATS */
}

/*
 *----------------------------------------------------------------------
 *
 * TclCreateExecEnv --
 *
 *	This procedure creates a new execution environment for Tcl bytecode
 *	execution. An ExecEnv points to a Tcl evaluation stack. An ExecEnv
 *	is typically created once for each Tcl interpreter (Interp
 *	structure) and recursively passed to TclExecuteByteCode to execute
 *	ByteCode sequences for nested commands.
 *
 * Results:
 *	A newly allocated ExecEnv is returned. This points to an empty
 *	evaluation stack of the standard initial size.
 *
 * Side effects:
 *	The bytecode interpreter is also initialized here, as this
 *	procedure will be called before any call to TclExecuteByteCode.
 *
 *----------------------------------------------------------------------
 */

#define TCL_STACK_INITIAL_SIZE 2000

ExecEnv *
TclCreateExecEnv(interp)
    Tcl_Interp *interp;		/* Interpreter for which the execution
				 * environment is being created. */
{
    ExecEnv *eePtr = (ExecEnv *) ckalloc(sizeof(ExecEnv));
    Tcl_Obj **stackPtr;

    stackPtr = (Tcl_Obj **)
	ckalloc((size_t) (TCL_STACK_INITIAL_SIZE * sizeof(Tcl_Obj *)));

    /*
     * Use the bottom pointer to keep a reference count; the 
     * execution environment holds a reference.
     */

    stackPtr++;
    eePtr->stackPtr = stackPtr;
    stackPtr[-1] = (Tcl_Obj *) ((char *) 1);

    eePtr->stackTop = -1;
    eePtr->stackEnd = (TCL_STACK_INITIAL_SIZE - 2);

    eePtr->errorInfo = Tcl_NewStringObj("::errorInfo", -1);
    Tcl_IncrRefCount(eePtr->errorInfo);

    eePtr->errorCode = Tcl_NewStringObj("::errorCode", -1);
    Tcl_IncrRefCount(eePtr->errorCode);

    Tcl_MutexLock(&execMutex);
    if (!execInitialized) {
	TclInitAuxDataTypeTable();
	InitByteCodeExecution(interp);
	execInitialized = 1;
    }
    Tcl_MutexUnlock(&execMutex);

    return eePtr;
}
#undef TCL_STACK_INITIAL_SIZE

/*
 *----------------------------------------------------------------------
 *
 * TclDeleteExecEnv --
 *
 *	Frees the storage for an ExecEnv.
 *
 * Results:
 *	None.
 *
 * Side effects:
 *	Storage for an ExecEnv and its contained storage (e.g. the
 *	evaluation stack) is freed.
 *
 *----------------------------------------------------------------------
 */

void
TclDeleteExecEnv(eePtr)
    ExecEnv *eePtr;		/* Execution environment to free. */
{
    if (eePtr->stackPtr[-1] == (Tcl_Obj *) ((char *) 1)) {
	ckfree((char *) (eePtr->stackPtr-1));
    } else {
	panic("ERROR: freeing an execEnv whose stack is still in use.\n");
    }
    TclDecrRefCount(eePtr->errorInfo);
    TclDecrRefCount(eePtr->errorCode);
    ckfree((char *) eePtr);
}

/*
 *----------------------------------------------------------------------
 *
 * TclFinalizeExecution --
 *
 *	Finalizes the execution environment setup so that it can be
 *	later reinitialized.
 *
 * Results:
 *	None.
 *
 * Side effects:
 *	After this call, the next time TclCreateExecEnv will be called
 *	it will call InitByteCodeExecution.
 *
 *----------------------------------------------------------------------
 */

void
TclFinalizeExecution()
{
    Tcl_MutexLock(&execMutex);
    execInitialized = 0;
    Tcl_MutexUnlock(&execMutex);
    TclFinalizeAuxDataTypeTable();
}

/*
 *----------------------------------------------------------------------
 *
 * GrowEvaluationStack --
 *
 *	This procedure grows a Tcl evaluation stack stored in an ExecEnv.
 *
 * Results:
 *	None.
 *
 * Side effects:
 *	The size of the evaluation stack is doubled.
 *
 *----------------------------------------------------------------------
 */

static void
GrowEvaluationStack(eePtr)
    register ExecEnv *eePtr; /* Points to the ExecEnv with an evaluation
			      * stack to enlarge. */
{
    /*
     * The current Tcl stack elements are stored from eePtr->stackPtr[0]
     * to eePtr->stackPtr[eePtr->stackEnd] (inclusive).
     */

    int currElems = (eePtr->stackEnd + 1);
    int newElems  = 2*currElems;
    int currBytes = currElems * sizeof(Tcl_Obj *);
    int newBytes  = 2*currBytes;
    Tcl_Obj **newStackPtr = (Tcl_Obj **) ckalloc((unsigned) newBytes);
    Tcl_Obj **oldStackPtr = eePtr->stackPtr;

    /*
     * We keep the stack reference count as a (char *), as that
     * works nicely as a portable pointer-sized counter.
     */

    char *refCount = (char *) oldStackPtr[-1];

    /*
     * Copy the existing stack items to the new stack space, free the old
     * storage if appropriate, and record the refCount of the new stack
     * held by the environment.
     */
 
    newStackPtr++;
    memcpy((VOID *) newStackPtr, (VOID *) oldStackPtr,
	   (size_t) currBytes);

    if (refCount == (char *) 1) {
	ckfree((VOID *) (oldStackPtr-1));
    } else {
	/*
	 * Remove the reference corresponding to the
	 * environment pointer.
	 */
	
	oldStackPtr[-1] = (Tcl_Obj *) (refCount-1);
    }

    eePtr->stackPtr = newStackPtr;
    eePtr->stackEnd = (newElems - 2); /* index of last usable item */
    newStackPtr[-1] = (Tcl_Obj *) ((char *) 1);	
}

/*
 *--------------------------------------------------------------
 *
 * Tcl_ExprObj --
 *
 *	Evaluate an expression in a Tcl_Obj.
 *
 * Results:
 *	A standard Tcl object result. If the result is other than TCL_OK,
 *	then the interpreter's result contains an error message. If the
 *	result is TCL_OK, then a pointer to the expression's result value
 *	object is stored in resultPtrPtr. In that case, the object's ref
 *	count is incremented to reflect the reference returned to the
 *	caller; the caller is then responsible for the resulting object
 *	and must, for example, decrement the ref count when it is finished
 *	with the object.
 *
 * Side effects:
 *	Any side effects caused by subcommands in the expression, if any.
 *	The interpreter result is not modified unless there is an error.
 *
 *--------------------------------------------------------------
 */

int
Tcl_ExprObj(interp, objPtr, resultPtrPtr)
    Tcl_Interp *interp;		/* Context in which to evaluate the
				 * expression. */
    register Tcl_Obj *objPtr;	/* Points to Tcl object containing
				 * expression to evaluate. */
    Tcl_Obj **resultPtrPtr;	/* Where the Tcl_Obj* that is the expression
				 * result is stored if no errors occur. */
{
    Interp *iPtr = (Interp *) interp;
    CompileEnv compEnv;		/* Compilation environment structure
				 * allocated in frame. */
    LiteralTable *localTablePtr = &(compEnv.localLitTable);
    register ByteCode *codePtr = NULL;
    				/* Tcl Internal type of bytecode.
				 * Initialized to avoid compiler warning. */
    AuxData *auxDataPtr;
    LiteralEntry *entryPtr;
    Tcl_Obj *saveObjPtr;
    char *string;
    int length, i, result;

    /*
     * First handle some common expressions specially.
     */

    string = Tcl_GetStringFromObj(objPtr, &length);
    if (length == 1) {
	if (*string == '0') {
	    *resultPtrPtr = Tcl_NewLongObj(0);
	    Tcl_IncrRefCount(*resultPtrPtr);
	    return TCL_OK;
	} else if (*string == '1') {
	    *resultPtrPtr = Tcl_NewLongObj(1);
	    Tcl_IncrRefCount(*resultPtrPtr);
	    return TCL_OK;
	}
    } else if ((length == 2) && (*string == '!')) {
	if (*(string+1) == '0') {
	    *resultPtrPtr = Tcl_NewLongObj(1);
	    Tcl_IncrRefCount(*resultPtrPtr);
	    return TCL_OK;
	} else if (*(string+1) == '1') {
	    *resultPtrPtr = Tcl_NewLongObj(0);
	    Tcl_IncrRefCount(*resultPtrPtr);
	    return TCL_OK;
	}
    }

    /*
     * Get the ByteCode from the object. If it exists, make sure it hasn't
     * been invalidated by, e.g., someone redefining a command with a
     * compile procedure (this might make the compiled code wrong). If
     * necessary, convert the object to be a ByteCode object and compile it.
     * Also, if the code was compiled in/for a different interpreter, we
     * recompile it.
     *
     * Precompiled expressions, however, are immutable and therefore
     * they are not recompiled, even if the epoch has changed.
     *
     */

    if (objPtr->typePtr == &tclByteCodeType) {
	codePtr = (ByteCode *) objPtr->internalRep.otherValuePtr;
	if (((Interp *) *codePtr->interpHandle != iPtr)
	        || (codePtr->compileEpoch != iPtr->compileEpoch)) {
            if (codePtr->flags & TCL_BYTECODE_PRECOMPILED) {
                if ((Interp *) *codePtr->interpHandle != iPtr) {
                    panic("Tcl_ExprObj: compiled expression jumped interps");
                }
	        codePtr->compileEpoch = iPtr->compileEpoch;
            } else {
                (*tclByteCodeType.freeIntRepProc)(objPtr);
                objPtr->typePtr = (Tcl_ObjType *) NULL;
            }
	}
    }
    if (objPtr->typePtr != &tclByteCodeType) {
	TclInitCompileEnv(interp, &compEnv, string, length);
	result = TclCompileExpr(interp, string, length, &compEnv);

	/*
	 * Free the compilation environment's literal table bucket array if
	 * it was dynamically allocated. 
	 */

	if (localTablePtr->buckets != localTablePtr->staticBuckets) {
	    ckfree((char *) localTablePtr->buckets);
	}
    
	if (result != TCL_OK) {
	    /*
	     * Compilation errors. Free storage allocated for compilation.
	     */

#ifdef TCL_COMPILE_DEBUG
	    TclVerifyLocalLiteralTable(&compEnv);
#endif /*TCL_COMPILE_DEBUG*/
	    entryPtr = compEnv.literalArrayPtr;
	    for (i = 0;  i < compEnv.literalArrayNext;  i++) {
		TclReleaseLiteral(interp, entryPtr->objPtr);
		entryPtr++;
	    }
#ifdef TCL_COMPILE_DEBUG
	    TclVerifyGlobalLiteralTable(iPtr);
#endif /*TCL_COMPILE_DEBUG*/
    
	    auxDataPtr = compEnv.auxDataArrayPtr;
	    for (i = 0;  i < compEnv.auxDataArrayNext;  i++) {
		if (auxDataPtr->type->freeProc != NULL) {
		    auxDataPtr->type->freeProc(auxDataPtr->clientData);
		}
		auxDataPtr++;
	    }
	    TclFreeCompileEnv(&compEnv);
	    return result;
	}

	/*
	 * Successful compilation. If the expression yielded no
	 * instructions, push an zero object as the expression's result.
	 */
	    
	if (compEnv.codeNext == compEnv.codeStart) {
	    TclEmitPush(TclRegisterLiteral(&compEnv, "0", 1, /*onHeap*/ 0),
	            &compEnv);
	}
	    
	/*
	 * Add a "done" instruction as the last instruction and change the
	 * object into a ByteCode object. Ownership of the literal objects
	 * and aux data items is given to the ByteCode object.
	 */

	compEnv.numSrcBytes = iPtr->termOffset;
	TclEmitOpcode(INST_DONE, &compEnv);
	TclInitByteCodeObj(objPtr, &compEnv);
	TclFreeCompileEnv(&compEnv);
	codePtr = (ByteCode *) objPtr->internalRep.otherValuePtr;
#ifdef TCL_COMPILE_DEBUG
	if (tclTraceCompile == 2) {
	    TclPrintByteCodeObj(interp, objPtr);
	}
#endif /* TCL_COMPILE_DEBUG */
    }

    /*
     * Execute the expression after first saving the interpreter's result.
     */
    
    saveObjPtr = Tcl_GetObjResult(interp);
    Tcl_IncrRefCount(saveObjPtr);
    Tcl_ResetResult(interp);

    /*
     * Increment the code's ref count while it is being executed. If
     * afterwards no references to it remain, free the code.
     */
    
    codePtr->refCount++;
    result = TclExecuteByteCode(interp, codePtr);
    codePtr->refCount--;
    if (codePtr->refCount <= 0) {
	TclCleanupByteCode(codePtr);
	objPtr->typePtr = NULL;
	objPtr->internalRep.otherValuePtr = NULL;
    }
    
    /*
     * If the expression evaluated successfully, store a pointer to its
     * value object in resultPtrPtr then restore the old interpreter result.
     * We increment the object's ref count to reflect the reference that we
     * are returning to the caller. We also decrement the ref count of the
     * interpreter's result object after calling Tcl_SetResult since we
     * next store into that field directly.
     */
    
    if (result == TCL_OK) {
	*resultPtrPtr = iPtr->objResultPtr;
	Tcl_IncrRefCount(iPtr->objResultPtr);
	
	Tcl_SetObjResult(interp, saveObjPtr);
    }
    TclDecrRefCount(saveObjPtr);
    return result;
}

/*
 *----------------------------------------------------------------------
 *
 * TclCompEvalObj --
 *
 *	This procedure evaluates the script contained in a Tcl_Obj by 
 *      first compiling it and then passing it to TclExecuteByteCode.
 *
 * Results:
 *	The return value is one of the return codes defined in tcl.h
 *	(such as TCL_OK), and interp->objResultPtr refers to a Tcl object
 *	that either contains the result of executing the code or an
 *	error message.
 *
 * Side effects:
 *	Almost certainly, depending on the ByteCode's instructions.
 *
 *----------------------------------------------------------------------
 */

int
TclCompEvalObj(interp, objPtr)
    Tcl_Interp *interp;
    Tcl_Obj *objPtr;
{
    register Interp *iPtr = (Interp *) interp;
    register ByteCode* codePtr;		/* Tcl Internal type of bytecode. */
    int oldCount = iPtr->cmdCount;	/* Used to tell whether any commands
					 * at all were executed. */
    char *script;
    int numSrcBytes;
    int result;
    Namespace *namespacePtr;


    /*
     * Check that the interpreter is ready to execute scripts
     */

    iPtr->numLevels++;
    if (TclInterpReady(interp) == TCL_ERROR) {
	iPtr->numLevels--;
	return TCL_ERROR;
    }

    if (iPtr->varFramePtr != NULL) {
        namespacePtr = iPtr->varFramePtr->nsPtr;
    } else {
        namespacePtr = iPtr->globalNsPtr;
    }

    /* 
     * If the object is not already of tclByteCodeType, compile it (and
     * reset the compilation flags in the interpreter; this should be 
     * done after any compilation).
     * Otherwise, check that it is "fresh" enough.
     */

    if (objPtr->typePtr != &tclByteCodeType) {
        recompileObj:
	iPtr->errorLine = 1; 
	result = tclByteCodeType.setFromAnyProc(interp, objPtr);
	if (result != TCL_OK) {
	    iPtr->numLevels--;
	    return result;
	}
	iPtr->evalFlags = 0;
	codePtr = (ByteCode *) objPtr->internalRep.otherValuePtr;
    } else {
	/*
	 * Make sure the Bytecode hasn't been invalidated by, e.g., someone 
	 * redefining a command with a compile procedure (this might make the 
	 * compiled code wrong). 
	 * The object needs to be recompiled if it was compiled in/for a 
	 * different interpreter, or for a different namespace, or for the 
	 * same namespace but with different name resolution rules. 
	 * Precompiled objects, however, are immutable and therefore
	 * they are not recompiled, even if the epoch has changed.
	 *
	 * To be pedantically correct, we should also check that the
	 * originating procPtr is the same as the current context procPtr
	 * (assuming one exists at all - none for global level).  This
	 * code is #def'ed out because [info body] was changed to never
	 * return a bytecode type object, which should obviate us from
	 * the extra checks here.
	 */
	codePtr = (ByteCode *) objPtr->internalRep.otherValuePtr;
	if (((Interp *) *codePtr->interpHandle != iPtr)
	        || (codePtr->compileEpoch != iPtr->compileEpoch)
#ifdef CHECK_PROC_ORIGINATION	/* [Bug: 3412 Pedantic] */
		|| (codePtr->procPtr != NULL && !(iPtr->varFramePtr &&
			iPtr->varFramePtr->procPtr == codePtr->procPtr))
#endif
	        || (codePtr->nsPtr != namespacePtr)
	        || (codePtr->nsEpoch != namespacePtr->resolverEpoch)) {
            if (codePtr->flags & TCL_BYTECODE_PRECOMPILED) {
                if ((Interp *) *codePtr->interpHandle != iPtr) {
                    panic("Tcl_EvalObj: compiled script jumped interps");
                }
	        codePtr->compileEpoch = iPtr->compileEpoch;
            } else {
		/*
		 * This byteCode is invalid: free it and recompile
		 */
                tclByteCodeType.freeIntRepProc(objPtr);
		goto recompileObj;
	    }
	}
    }

    /*
     * Execute the commands. If the code was compiled from an empty string,
     * don't bother executing the code.
     */

    numSrcBytes = codePtr->numSrcBytes;
    if ((numSrcBytes > 0) || (codePtr->flags & TCL_BYTECODE_PRECOMPILED)) {
	/*
	 * Increment the code's ref count while it is being executed. If
	 * afterwards no references to it remain, free the code.
	 */
	
	codePtr->refCount++;
	result = TclExecuteByteCode(interp, codePtr);
	codePtr->refCount--;
	if (codePtr->refCount <= 0) {
	    TclCleanupByteCode(codePtr);
	}
    } else {
	result = TCL_OK;
    }
    iPtr->numLevels--;


    /*
     * If no commands at all were executed, check for asynchronous
     * handlers so that they at least get one change to execute.
     * This is needed to handle event loops written in Tcl with
     * empty bodies.
     */

    if ((oldCount == iPtr->cmdCount) && Tcl_AsyncReady()) {
	result = Tcl_AsyncInvoke(interp, result);
    

	/*
	 * If an error occurred, record information about what was being
	 * executed when the error occurred.
	 */
	
	if ((result == TCL_ERROR) && !(iPtr->flags & ERR_ALREADY_LOGGED)) {
	    script = Tcl_GetStringFromObj(objPtr, &numSrcBytes);
	    Tcl_LogCommandInfo(interp, script, script, numSrcBytes);
	}
    }

    /*
     * Set the interpreter's termOffset member to the offset of the
     * character just after the last one executed. We approximate the offset
     * of the last character executed by using the number of characters
     * compiled. 
     */

    iPtr->termOffset = numSrcBytes;
    iPtr->flags &= ~ERR_ALREADY_LOGGED;

    return result;
}

/*
 *----------------------------------------------------------------------
 *
 * TclExecuteByteCode --
 *
 *	This procedure executes the instructions of a ByteCode structure.
 *	It returns when a "done" instruction is executed or an error occurs.
 *
 * Results:
 *	The return value is one of the return codes defined in tcl.h
 *	(such as TCL_OK), and interp->objResultPtr refers to a Tcl object
 *	that either contains the result of executing the code or an
 *	error message.
 *
 * Side effects:
 *	Almost certainly, depending on the ByteCode's instructions.
 *
 *----------------------------------------------------------------------
 */
 
static int
TclExecuteByteCode(interp, codePtr)
    Tcl_Interp *interp;		/* Token for command interpreter. */
    ByteCode *codePtr;		/* The bytecode sequence to interpret. */
{
    Interp *iPtr = (Interp *) interp;
    ExecEnv *eePtr = iPtr->execEnvPtr;
    				/* Points to the execution environment. */
    register Tcl_Obj **stackPtr = eePtr->stackPtr;
    				/* Cached evaluation stack base pointer. */
    register int stackTop = eePtr->stackTop;
    				/* Cached top index of evaluation stack. */
    register unsigned char *pc = codePtr->codeStart;
				/* The current program counter. */
    int opnd;			/* Current instruction's operand byte(s). */
    int pcAdjustment;		/* Hold pc adjustment after instruction. */
    int initStackTop = stackTop;/* Stack top at start of execution. */
    ExceptionRange *rangePtr;	/* Points to closest loop or catch exception
				 * range enclosing the pc. Used by various
				 * instructions and processCatch to
				 * process break, continue, and errors. */
    int result = TCL_OK;	/* Return code returned after execution. */
    int storeFlags;
    Tcl_Obj *valuePtr, *value2Ptr, *objPtr;
    char *bytes;
    int length;
    long i = 0;			/* Init. avoids compiler warning. */
    Tcl_WideInt w;
    register int cleanup;
    Tcl_Obj *objResultPtr;
    char *part1, *part2;
    Var *varPtr, *arrayPtr;
    CallFrame *varFramePtr = iPtr->varFramePtr;
#ifdef TCL_COMPILE_DEBUG
    int traceInstructions = (tclTraceExec == 3);
    char cmdNameBuf[21];
#endif

    /*
     * This procedure uses a stack to hold information about catch commands.
     * This information is the current operand stack top when starting to
     * execute the code for each catch command. It starts out with stack-
     * allocated space but uses dynamically-allocated storage if needed.
     */

#define STATIC_CATCH_STACK_SIZE 4
    int (catchStackStorage[STATIC_CATCH_STACK_SIZE]);
    int *catchStackPtr = catchStackStorage;
    int catchTop = -1;

#ifdef TCL_COMPILE_DEBUG
    if (tclTraceExec >= 2) {
	PrintByteCodeInfo(codePtr);
	fprintf(stdout, "  Starting stack top=%d\n", eePtr->stackTop);
	fflush(stdout);
    }
    opnd = 0;			/* Init. avoids compiler warning. */       
#endif
    
#ifdef TCL_COMPILE_STATS
    iPtr->stats.numExecutions++;
#endif

    /*
     * Make sure the catch stack is large enough to hold the maximum number
     * of catch commands that could ever be executing at the same time. This
     * will be no more than the exception range array's depth.
     */

    if (codePtr->maxExceptDepth > STATIC_CATCH_STACK_SIZE) {
	catchStackPtr = (int *)
	        ckalloc(codePtr->maxExceptDepth * sizeof(int));
    }

    /*
     * Make sure the stack has enough room to execute this ByteCode.
     */

    while ((stackTop + codePtr->maxStackDepth) > eePtr->stackEnd) {
        GrowEvaluationStack(eePtr); 
        stackPtr = eePtr->stackPtr;
    }

    /*
     * 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 cleanup.
     */
    
    cleanupV_pushObjResultPtr:
    switch (cleanup) {
        case 0:
	    stackPtr[++stackTop] = (objResultPtr);
	    goto cleanup0;
        default:
	    cleanup -= 2;
	    while (cleanup--) {
		valuePtr = POP_OBJECT();
		TclDecrRefCount(valuePtr);
	    }
        case 2: 
        cleanup2_pushObjResultPtr:
	    valuePtr = POP_OBJECT();
	    TclDecrRefCount(valuePtr);
        case 1: 
        cleanup1_pushObjResultPtr:
	    valuePtr = stackPtr[stackTop];
	    TclDecrRefCount(valuePtr);
    }
    stackPtr[stackTop] = objResultPtr;
    goto cleanup0;
    
    cleanupV:
    switch (cleanup) {
        default:
	    cleanup -= 2;
	    while (cleanup--) {
		valuePtr = POP_OBJECT();
		TclDecrRefCount(valuePtr);
	    }
        case 2: 
        cleanup2:
	    valuePtr = POP_OBJECT();
	    TclDecrRefCount(valuePtr);
        case 1: 
        cleanup1:
	    valuePtr = POP_OBJECT();
	    TclDecrRefCount(valuePtr);
        case 0:
	    /*
	     * We really want to do nothing now, but this is needed
	     * for some compilers (SunPro CC)
	     */
	    break;
    }

    cleanup0:
    
#ifdef TCL_COMPILE_DEBUG
    ValidatePcAndStackTop(codePtr, pc, stackTop, initStackTop);
    if (traceInstructions) {
	fprintf(stdout, "%2d: %2d ", iPtr->numLevels, stackTop);
	TclPrintInstruction(codePtr, pc);
	fflush(stdout);
    }
#endif /* TCL_COMPILE_DEBUG */
    
#ifdef TCL_COMPILE_STATS    
    iPtr->stats.instructionCount[*pc]++;
#endif
    switch (*pc) {
    case INST_DONE:
	if (stackTop <= initStackTop) {
	    stackTop--;
	    goto abnormalReturn;
	}
	
	/*
	 * Set the interpreter's object result to point to the 
	 * topmost object from the stack, and check for a possible
	 * [catch]. The stackTop's level and refCount will be handled 
	 * by "processCatch" or "abnormalReturn".
	 */

	valuePtr = stackPtr[stackTop];
	Tcl_SetObjResult(interp, valuePtr);
#ifdef TCL_COMPILE_DEBUG	    
	TRACE_WITH_OBJ(("=> return code=%d, result=", result),
	        iPtr->objResultPtr);
	if (traceInstructions) {
	    fprintf(stdout, "\n");
	}
#endif
	goto checkForCatch;
	
    case INST_PUSH1:
	objResultPtr = codePtr->objArrayPtr[TclGetUInt1AtPtr(pc+1)];
	TRACE_WITH_OBJ(("%u => ", TclGetInt1AtPtr(pc+1)), objResultPtr);
	NEXT_INST_F(2, 0, 1);

    case INST_PUSH4:
	objResultPtr = codePtr->objArrayPtr[TclGetUInt4AtPtr(pc+1)];
	TRACE_WITH_OBJ(("%u => ", TclGetUInt4AtPtr(pc+1)), objResultPtr);
	NEXT_INST_F(5, 0, 1);

    case INST_POP:
	TRACE_WITH_OBJ(("=> discarding "), stackPtr[stackTop]);
	valuePtr = POP_OBJECT();
	TclDecrRefCount(valuePtr);
	NEXT_INST_F(1, 0, 0);
	
    case INST_DUP:
	objResultPtr = stackPtr[stackTop];
	TRACE_WITH_OBJ(("=> "), objResultPtr);
	NEXT_INST_F(1, 0, 1);

    case INST_OVER:
	opnd = TclGetUInt4AtPtr( pc+1 );
	objResultPtr = stackPtr[ stackTop - opnd ];
	TRACE_WITH_OBJ(("=> "), objResultPtr);
	NEXT_INST_F(5, 0, 1);

    case INST_CONCAT1:
	opnd = TclGetUInt1AtPtr(pc+1);
	{
	    int totalLen = 0;
	    
	    /*
	     * Concatenate strings (with no separators) from the top
	     * opnd items on the stack starting with the deepest item.
	     * First, determine how many characters are needed.
	     */

	    for (i = (stackTop - (opnd-1));  i <= stackTop;  i++) {
		bytes = Tcl_GetStringFromObj(stackPtr[i], &length);
		if (bytes != NULL) {
		    totalLen += length;
		}
	    }

	    /*
	     * Initialize the new append string object by appending the
	     * strings of the opnd stack objects. Also pop the objects. 
	     */

	    TclNewObj(objResultPtr);
	    if (totalLen > 0) {
		char *p = (char *) ckalloc((unsigned) (totalLen + 1));
		objResultPtr->bytes = p;
		objResultPtr->length = totalLen;
		for (i = (stackTop - (opnd-1));  i <= stackTop;  i++) {
		    valuePtr = stackPtr[i];
		    bytes = Tcl_GetStringFromObj(valuePtr, &length);
		    if (bytes != NULL) {
			memcpy((VOID *) p, (VOID *) bytes,
			       (size_t) length);
			p += length;
		    }
		}
		*p = '\0';
	    }
		
	    TRACE_WITH_OBJ(("%u => ", opnd), objResultPtr);
	    NEXT_INST_V(2, opnd, 1);
	}
	    
    case INST_INVOKE_STK4:
	opnd = TclGetUInt4AtPtr(pc+1);
	pcAdjustment = 5;
	goto doInvocation;

    case INST_INVOKE_STK1:
	opnd = TclGetUInt1AtPtr(pc+1);
	pcAdjustment = 2;
	    
    doInvocation:
	{
	    int objc = opnd; /* The number of arguments. */
	    Tcl_Obj **objv;	 /* The array of argument objects. */

	    /*
	     * We keep the stack reference count as a (char *), as that
	     * works nicely as a portable pointer-sized counter.
	     */

	    char **preservedStackRefCountPtr;
	    
	    /* 
	     * Reference to memory block containing
	     * objv array (must be kept live throughout
	     * trace and command invokations.) 
	     */

	    objv = &(stackPtr[stackTop - (objc-1)]);

#ifdef TCL_COMPILE_DEBUG
	    if (tclTraceExec >= 2) {
		if (traceInstructions) {
		    strncpy(cmdNameBuf, TclGetString(objv[0]), 20);
		    TRACE(("%u => call ", objc));
		} else {
		    fprintf(stdout, "%d: (%u) invoking ",
			    iPtr->numLevels,
			    (unsigned int)(pc - codePtr->codeStart));
		}
		for (i = 0;  i < objc;  i++) {
		    TclPrintObject(stdout, objv[i], 15);
		    fprintf(stdout, " ");
		}
		fprintf(stdout, "\n");
		fflush(stdout);
	    }
#endif /*TCL_COMPILE_DEBUG*/

	    /* 
	     * If trace procedures will be called, we need a
	     * command string to pass to TclEvalObjvInternal; note 
	     * that a copy of the string will be made there to 
	     * include the ending \0.
	     */

	    bytes = NULL;
	    length = 0;
	    if (iPtr->tracePtr != NULL) {
		Trace *tracePtr, *nextTracePtr;
		    
		for (tracePtr = iPtr->tracePtr;  tracePtr != NULL;
		     tracePtr = nextTracePtr) {
		    nextTracePtr = tracePtr->nextPtr;
		    if (tracePtr->level == 0 ||
			iPtr->numLevels <= tracePtr->level) {
			/*
			 * Traces will be called: get command string
			 */

			bytes = GetSrcInfoForPc(pc, codePtr, &length);
			break;
		    }
		}
	    } else {		
		Command *cmdPtr;
		cmdPtr = (Command *) Tcl_GetCommandFromObj(interp, objv[0]);
		if ((cmdPtr != NULL) && (cmdPtr->flags & CMD_HAS_EXEC_TRACES)) {
		    bytes = GetSrcInfoForPc(pc, codePtr, &length);
		}
	    }		

	    /*
	     * A reference to part of the stack vector itself
	     * escapes our control: increase its refCount
	     * to stop it from being deallocated by a recursive
	     * call to ourselves.  The extra variable is needed
	     * because all others are liable to change due to the
	     * trace procedures.
	     */

	    preservedStackRefCountPtr = (char **) (stackPtr-1);
	    ++*preservedStackRefCountPtr;

	    /*
	     * Finally, let TclEvalObjvInternal handle the command. 
	     */

	    DECACHE_STACK_INFO();
	    Tcl_ResetResult(interp);
	    result = TclEvalObjvInternal(interp, objc, objv, bytes, length, 0);
	    CACHE_STACK_INFO();

	    /*
	     * If the old stack is going to be released, it is
	     * safe to do so now, since no references to objv are
	     * going to be used from now on.
	     */

	    --*preservedStackRefCountPtr;
	    if (*preservedStackRefCountPtr == (char *) 0) {
		ckfree((VOID *) preservedStackRefCountPtr);
	    }	    

	    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=",
		        objc, cmdNameBuf), Tcl_GetObjResult(interp));

		objResultPtr = Tcl_GetObjResult(interp);

		/*
		 * Reset the interp's result to avoid possible duplications
		 * of large objects [Bug 781585]. We do not call
		 * Tcl_ResetResult() to avoid any side effects caused by
		 * the resetting of errorInfo and errorCode [Bug 804681], 
		 * which are not needed here. We chose instead to manipulate
		 * the interp's object result directly.
		 *
		 * Note that the result object is now in objResultPtr, it
		 * keeps the refCount it had in its role of iPtr->objResultPtr.
		 */
		{
		    Tcl_Obj *newObjResultPtr;
		    TclNewObj(newObjResultPtr);
		    Tcl_IncrRefCount(newObjResultPtr);
		    iPtr->objResultPtr = newObjResultPtr;
		}

		NEXT_INST_V(pcAdjustment, opnd, -1);
	    } else {
		cleanup = opnd;
		goto processExceptionReturn;
	    }
	}

    case INST_EVAL_STK:
	/*
	 * Note to maintainers: it is important that INST_EVAL_STK
	 * pop its argument from the stack before jumping to
	 * checkForCatch! DO NOT OPTIMISE!
	 */

	objPtr = stackPtr[stackTop];
	DECACHE_STACK_INFO();
	result = TclCompEvalObj(interp, objPtr);
	CACHE_STACK_INFO();
	if (result == TCL_OK) {
	    /*
	     * Normal return; push the eval's object result.
	     */

	    objResultPtr = Tcl_GetObjResult(interp);
	    TRACE_WITH_OBJ(("\"%.30s\" => ", O2S(objPtr)),
			   Tcl_GetObjResult(interp));

	    /*
	     * Reset the interp's result to avoid possible duplications
	     * of large objects [Bug 781585]. We do not call
	     * Tcl_ResetResult() to avoid any side effects caused by
	     * the resetting of errorInfo and errorCode [Bug 804681], 
	     * which are not needed here. We chose instead to manipulate
	     * the interp's object result directly.
	     *
	     * Note that the result object is now in objResultPtr, it
	     * keeps the refCount it had in its role of iPtr->objResultPtr.
	     */
	    {
	        Tcl_Obj *newObjResultPtr;
		TclNewObj(newObjResultPtr);
		Tcl_IncrRefCount(newObjResultPtr);
		iPtr->objResultPtr = newObjResultPtr;
	    }

	    NEXT_INST_F(1, 1, -1);
	} else {
	    cleanup = 1;
	    goto processExceptionReturn;
	}

    case INST_EXPR_STK:
	objPtr = stackPtr[stackTop];
	DECACHE_STACK_INFO();
	Tcl_ResetResult(interp);
	result = Tcl_ExprObj(interp, objPtr, &valuePtr);
	CACHE_STACK_INFO();
	if (result != TCL_OK) {
	    TRACE_WITH_OBJ(("\"%.30s\" => ERROR: ", 
	        O2S(objPtr)), Tcl_GetObjResult(interp));
	    goto checkForCatch;
	}
	objResultPtr = valuePtr;
	TRACE_WITH_OBJ(("\"%.30s\" => ", O2S(objPtr)), valuePtr);
	NEXT_INST_F(1, 1, -1); /* already has right refct */

    /*
     * ---------------------------------------------------------
     *     Start of INST_LOAD instructions.
     *
     * WARNING: more 'goto' here than your doctor recommended!
     * The different instructions set the value of some variables
     * and then jump to somme common execution code.
     */

    case INST_LOAD_SCALAR1:
	opnd = TclGetUInt1AtPtr(pc+1);
	varPtr = &(varFramePtr->compiledLocals[opnd]);
	part1 = varPtr->name;
	while (TclIsVarLink(varPtr)) {
	    varPtr = varPtr->value.linkPtr;
	}
	TRACE(("%u => ", opnd));
	if (TclIsVarScalar(varPtr) && !TclIsVarUndefined(varPtr) 
	        && (varPtr->tracePtr == NULL)) {
	    /*
	     * No errors, no traces: just get the value.
	     */
	    objResultPtr = varPtr->value.objPtr;
	    TRACE_APPEND(("%.30s\n", O2S(objResultPtr)));
	    NEXT_INST_F(2, 0, 1);
	}
	pcAdjustment = 2;
	cleanup = 0;
	arrayPtr = NULL;
	part2 = NULL;
	goto doCallPtrGetVar;

    case INST_LOAD_SCALAR4:
	opnd = TclGetUInt4AtPtr(pc+1);
	varPtr = &(varFramePtr->compiledLocals[opnd]);
	part1 = varPtr->name;
	while (TclIsVarLink(varPtr)) {
	    varPtr = varPtr->value.linkPtr;
	}
	TRACE(("%u => ", opnd));
	if (TclIsVarScalar(varPtr) && !TclIsVarUndefined(varPtr) 
	        && (varPtr->tracePtr == NULL)) {
	    /*
	     * No errors, no traces: just get the value.
	     */
	    objResultPtr = varPtr->value.objPtr;
	    TRACE_APPEND(("%.30s\n", O2S(objResultPtr)));
	    NEXT_INST_F(5, 0, 1);
	}
	pcAdjustment = 5;
	cleanup = 0;
	arrayPtr = NULL;
	part2 = NULL;
	goto doCallPtrGetVar;

    case INST_LOAD_ARRAY_STK:
	cleanup = 2;
	part2 = Tcl_GetString(stackPtr[stackTop]);  /* element name */
	objPtr = stackPtr[stackTop-1]; /* array name */
	TRACE(("\"%.30s(%.30s)\" => ", O2S(objPtr), part2));
	goto doLoadStk;

    case INST_LOAD_STK:
    case INST_LOAD_SCALAR_STK:
	cleanup = 1;
	part2 = NULL;
	objPtr = stackPtr[stackTop]; /* variable name */
	TRACE(("\"%.30s\" => ", O2S(objPtr)));

    doLoadStk:
	part1 = TclGetString(objPtr);
	varPtr = TclObjLookupVar(interp, objPtr, part2, 
	         TCL_LEAVE_ERR_MSG, "read",
                 /*createPart1*/ 0,
	         /*createPart2*/ 1, &arrayPtr);
	if (varPtr == NULL) {
	    TRACE_APPEND(("ERROR: %.30s\n", O2S(Tcl_GetObjResult(interp))));
	    result = TCL_ERROR;
	    goto checkForCatch;
	}
	if (TclIsVarScalar(varPtr) && !TclIsVarUndefined(varPtr) 
	        && (varPtr->tracePtr == NULL)
	        && ((arrayPtr == NULL) 
		        || (arrayPtr->tracePtr == NULL))) {
	    /*
	     * No errors, no traces: just get the value.
	     */
	    objResultPtr = varPtr->value.objPtr;
	    TRACE_APPEND(("%.30s\n", O2S(objResultPtr)));
	    NEXT_INST_V(1, cleanup, 1);
	}
	pcAdjustment = 1;
	goto doCallPtrGetVar;

    case INST_LOAD_ARRAY4:
	opnd = TclGetUInt4AtPtr(pc+1);
	pcAdjustment = 5;
	goto doLoadArray;

    case INST_LOAD_ARRAY1:
	opnd = TclGetUInt1AtPtr(pc+1);
	pcAdjustment = 2;
    
    doLoadArray:
	part2 = TclGetString(stackPtr[stackTop]);
	arrayPtr = &(varFramePtr->compiledLocals[opnd]);
	part1 = arrayPtr->name;
	while (TclIsVarLink(arrayPtr)) {
	    arrayPtr = arrayPtr->value.linkPtr;
	}
	TRACE(("%u \"%.30s\" => ", opnd, part2));
	varPtr = TclLookupArrayElement(interp, part1, part2, 
	        TCL_LEAVE_ERR_MSG, "read", 0, 1, arrayPtr);
	if (varPtr == NULL) {
	    TRACE_APPEND(("ERROR: %.30s\n", O2S(Tcl_GetObjResult(interp))));
	    result = TCL_ERROR;
	    goto checkForCatch;
	}
	if (TclIsVarScalar(varPtr) && !TclIsVarUndefined(varPtr) 
	        && (varPtr->tracePtr == NULL)
	        && ((arrayPtr == NULL) 
		        || (arrayPtr->tracePtr == NULL))) {
	    /*
	     * No errors, no traces: just get the value.
	     */
	    objResultPtr = varPtr->value.objPtr;
	    TRACE_APPEND(("%.30s\n", O2S(objResultPtr)));
	    NEXT_INST_F(pcAdjustment, 1, 1);
	}
	cleanup = 1;
	goto doCallPtrGetVar;

    doCallPtrGetVar:
	/*
	 * There are either errors or the variable is traced:
	 * call TclPtrGetVar to process fully.
	 */

	DECACHE_STACK_INFO();
	objResultPtr = TclPtrGetVar(interp, varPtr, arrayPtr, part1, 
	        part2, TCL_LEAVE_ERR_MSG);
	CACHE_STACK_INFO();
	if (objResultPtr == NULL) {
	    TRACE_APPEND(("ERROR: %.30s\n", O2S(Tcl_GetObjResult(interp))));
	    result = TCL_ERROR;
	    goto checkForCatch;
	}
	TRACE_APPEND(("%.30s\n", O2S(objResultPtr)));
	NEXT_INST_V(pcAdjustment, cleanup, 1);

    /*
     *     End of INST_LOAD instructions.
     * ---------------------------------------------------------
     */

    /*
     * ---------------------------------------------------------
     *     Start of INST_STORE and related instructions.
     *
     * WARNING: more 'goto' here than your doctor recommended!
     * The different instructions set the value of some variables
     * and then jump to somme common execution code.
     */

    case INST_LAPPEND_STK:
	valuePtr = stackPtr[stackTop]; /* value to append */
	part2 = NULL;
	storeFlags = (TCL_LEAVE_ERR_MSG | TCL_APPEND_VALUE 
		      | TCL_LIST_ELEMENT | TCL_TRACE_READS);
	goto doStoreStk;

    case INST_LAPPEND_ARRAY_STK:
	valuePtr = stackPtr[stackTop]; /* value to append */
	part2 = TclGetString(stackPtr[stackTop - 1]);
	storeFlags = (TCL_LEAVE_ERR_MSG | TCL_APPEND_VALUE 
		      | TCL_LIST_ELEMENT | TCL_TRACE_READS);
	goto doStoreStk;

    case INST_APPEND_STK:
	valuePtr = stackPtr[stackTop]; /* value to append */
	part2 = NULL;
	storeFlags = (TCL_LEAVE_ERR_MSG | TCL_APPEND_VALUE);
	goto doStoreStk;

    case INST_APPEND_ARRAY_STK:
	valuePtr = stackPtr[stackTop]; /* value to append */
	part2 = TclGetString(stackPtr[stackTop - 1]);
	storeFlags = (TCL_LEAVE_ERR_MSG | TCL_APPEND_VALUE);
	goto doStoreStk;

    case INST_STORE_ARRAY_STK:
	valuePtr = stackPtr[stackTop];
	part2 = TclGetString(stackPtr[stackTop - 1]);
	storeFlags = TCL_LEAVE_ERR_MSG;
	goto doStoreStk;

    case INST_STORE_STK:
    case INST_STORE_SCALAR_STK:
	valuePtr = stackPtr[stackTop];
	part2 = NULL;
	storeFlags = TCL_LEAVE_ERR_MSG;

    doStoreStk:
	objPtr = stackPtr[stackTop - 1 - (part2 != NULL)]; /* variable name */
	part1 = TclGetString(objPtr);
#ifdef TCL_COMPILE_DEBUG
	if (part2 == NULL) {
	    TRACE(("\"%.30s\" <- \"%.30s\" =>", 
	            part1, O2S(valuePtr)));
	} else {
	    TRACE(("\"%.30s(%.30s)\" <- \"%.30s\" => ",
		    part1, part2, O2S(valuePtr)));
	}
#endif
	varPtr = TclObjLookupVar(interp, objPtr, part2, 
	         TCL_LEAVE_ERR_MSG, "set",
                 /*createPart1*/ 1,
	         /*createPart2*/ 1, &arrayPtr);
	if (varPtr == NULL) {
	    TRACE_APPEND(("ERROR: %.30s\n", O2S(Tcl_GetObjResult(interp))));
	    result = TCL_ERROR;
	    goto checkForCatch;
	}
	cleanup = ((part2 == NULL)? 2 : 3);
	pcAdjustment = 1;
	goto doCallPtrSetVar;

    case INST_LAPPEND_ARRAY4:
	opnd = TclGetUInt4AtPtr(pc+1);
	pcAdjustment = 5;
	storeFlags = (TCL_LEAVE_ERR_MSG | TCL_APPEND_VALUE 
		      | TCL_LIST_ELEMENT | TCL_TRACE_READS);
	goto doStoreArray;

    case INST_LAPPEND_ARRAY1:
	opnd = TclGetUInt1AtPtr(pc+1);
	pcAdjustment = 2;
	storeFlags = (TCL_LEAVE_ERR_MSG | TCL_APPEND_VALUE 
		      | TCL_LIST_ELEMENT | TCL_TRACE_READS);
	goto doStoreArray;

    case INST_APPEND_ARRAY4:
	opnd = TclGetUInt4AtPtr(pc+1);
	pcAdjustment = 5;
	storeFlags = (TCL_LEAVE_ERR_MSG | TCL_APPEND_VALUE);
	goto doStoreArray;

    case INST_APPEND_ARRAY1:
	opnd = TclGetUInt1AtPtr(pc+1);
	pcAdjustment = 2;
	storeFlags = (TCL_LEAVE_ERR_MSG | TCL_APPEND_VALUE);
	goto doStoreArray;

    case INST_STORE_ARRAY4:
	opnd = TclGetUInt4AtPtr(pc+1);
	pcAdjustment = 5;
	storeFlags = TCL_LEAVE_ERR_MSG;
	goto doStoreArray;

    case INST_STORE_ARRAY1:
	opnd = TclGetUInt1AtPtr(pc+1);
	pcAdjustment = 2;
	storeFlags = TCL_LEAVE_ERR_MSG;
	    
    doStoreArray:
	valuePtr = stackPtr[stackTop];
	part2 = TclGetString(stackPtr[stackTop - 1]);
	arrayPtr = &(varFramePtr->compiledLocals[opnd]);
	part1 = arrayPtr->name;
	TRACE(("%u \"%.30s\" <- \"%.30s\" => ",
		    opnd, part2, O2S(valuePtr)));
	while (TclIsVarLink(arrayPtr)) {
	    arrayPtr = arrayPtr->value.linkPtr;
	}
	varPtr = TclLookupArrayElement(interp, part1, part2, 
	        TCL_LEAVE_ERR_MSG, "set", 1, 1, arrayPtr);
	if (varPtr == NULL) {
	    TRACE_APPEND(("ERROR: %.30s\n", O2S(Tcl_GetObjResult(interp))));
	    result = TCL_ERROR;
	    goto checkForCatch;
	}
	cleanup = 2;
	goto doCallPtrSetVar;

    case INST_LAPPEND_SCALAR4:
	opnd = TclGetUInt4AtPtr(pc+1);
	pcAdjustment = 5;
	storeFlags = (TCL_LEAVE_ERR_MSG | TCL_APPEND_VALUE 
		      | TCL_LIST_ELEMENT | TCL_TRACE_READS);
	goto doStoreScalar;

    case INST_LAPPEND_SCALAR1:
	opnd = TclGetUInt1AtPtr(pc+1);
	pcAdjustment = 2;	    
	storeFlags = (TCL_LEAVE_ERR_MSG | TCL_APPEND_VALUE 
		      | TCL_LIST_ELEMENT | TCL_TRACE_READS);
	goto doStoreScalar;

    case INST_APPEND_SCALAR4:
	opnd = TclGetUInt4AtPtr(pc+1);
	pcAdjustment = 5;
	storeFlags = (TCL_LEAVE_ERR_MSG | TCL_APPEND_VALUE);
	goto doStoreScalar;

    case INST_APPEND_SCALAR1:
	opnd = TclGetUInt1AtPtr(pc+1);
	pcAdjustment = 2;	    
	storeFlags = (TCL_LEAVE_ERR_MSG | TCL_APPEND_VALUE);
	goto doStoreScalar;

    case INST_STORE_SCALAR4:
	opnd = TclGetUInt4AtPtr(pc+1);
	pcAdjustment = 5;
	storeFlags = TCL_LEAVE_ERR_MSG;
	goto doStoreScalar;

    case INST_STORE_SCALAR1:
	opnd = TclGetUInt1AtPtr(pc+1);
	pcAdjustment = 2;
	storeFlags = TCL_LEAVE_ERR_MSG;

    doStoreScalar:
	valuePtr = stackPtr[stackTop];
	varPtr = &(varFramePtr->compiledLocals[opnd]);
	part1 = varPtr->name;
	TRACE(("%u <- \"%.30s\" => ", opnd, O2S(valuePtr)));
	while (TclIsVarLink(varPtr)) {
	    varPtr = varPtr->value.linkPtr;
	}
	cleanup = 1;
	arrayPtr = NULL;
	part2 = NULL;

    doCallPtrSetVar:
	if ((storeFlags == TCL_LEAVE_ERR_MSG)
	        && !((varPtr->flags & VAR_IN_HASHTABLE) 
		        && (varPtr->hPtr == NULL))
	        && (varPtr->tracePtr == NULL)
	        && (TclIsVarScalar(varPtr) 
		        || TclIsVarUndefined(varPtr))
	        && ((arrayPtr == NULL) 
		        || (arrayPtr->tracePtr == NULL))) {
	    /*
	     * No traces, no errors, plain 'set': we can safely inline.
	     * The value *will* be set to what's requested, so that 
	     * the stack top remains pointing to the same Tcl_Obj.
	     */
	    valuePtr = varPtr->value.objPtr;
	    objResultPtr = stackPtr[stackTop];
	    if (valuePtr != objResultPtr) {
		if (valuePtr != NULL) {
		    TclDecrRefCount(valuePtr);
		} else {
		    TclSetVarScalar(varPtr);
		    TclClearVarUndefined(varPtr);
		}
		varPtr->value.objPtr = objResultPtr;
		Tcl_IncrRefCount(objResultPtr);
	    }
#ifndef TCL_COMPILE_DEBUG
	    if (*(pc+pcAdjustment) == INST_POP) {
		NEXT_INST_V((pcAdjustment+1), cleanup, 0);
	    }
#else
	TRACE_APPEND(("%.30s\n", O2S(objResultPtr)));
#endif
	    NEXT_INST_V(pcAdjustment, cleanup, 1);
	} else {
	    DECACHE_STACK_INFO();
	    objResultPtr = TclPtrSetVar(interp, varPtr, arrayPtr, 
	            part1, part2, valuePtr, storeFlags);
	    CACHE_STACK_INFO();
	    if (objResultPtr == NULL) {
		TRACE_APPEND(("ERROR: %.30s\n", O2S(Tcl_GetObjResult(interp))));
		result = TCL_ERROR;
		goto checkForCatch;
	    }
	}
#ifndef TCL_COMPILE_DEBUG
	if (*(pc+pcAdjustment) == INST_POP) {
	    NEXT_INST_V((pcAdjustment+1), cleanup, 0);
	}
#endif
	TRACE_APPEND(("%.30s\n", O2S(objResultPtr)));
	NEXT_INST_V(pcAdjustment, cleanup, 1);


    /*
     *     End of INST_STORE and related instructions.
     * ---------------------------------------------------------
     */

    /*
     * ---------------------------------------------------------
     *     Start of INST_INCR instructions.
     *
     * WARNING: more 'goto' here than your doctor recommended!
     * The different instructions set the value of some variables
     * and then jump to somme common execution code.
     */

    case INST_INCR_SCALAR1:
    case INST_INCR_ARRAY1:
    case INST_INCR_ARRAY_STK:
    case INST_INCR_SCALAR_STK:
    case INST_INCR_STK:
	opnd = TclGetUInt1AtPtr(pc+1);
	valuePtr = stackPtr[stackTop];
	if (valuePtr->typePtr == &tclIntType) {
	    i = valuePtr->internalRep.longValue;
	} else if (valuePtr->typePtr == &tclWideIntType) {
	    TclGetLongFromWide(i,valuePtr);
	} else {
	    REQUIRE_WIDE_OR_INT(result, valuePtr, i, w);
	    if (result != TCL_OK) {
		TRACE_WITH_OBJ(("%u (by %s) => ERROR converting increment amount to int: ",
		        opnd, O2S(valuePtr)), Tcl_GetObjResult(interp));
		DECACHE_STACK_INFO();
		Tcl_AddErrorInfo(interp, "\n    (reading increment)");
		CACHE_STACK_INFO();
		goto checkForCatch;
	    }
	    FORCE_LONG(valuePtr, i, w);
	}
	stackTop--;
	TclDecrRefCount(valuePtr);
	switch (*pc) {
	    case INST_INCR_SCALAR1:
		pcAdjustment = 2;
		goto doIncrScalar;
	    case INST_INCR_ARRAY1:
		pcAdjustment = 2;
		goto doIncrArray;
	    default:
		pcAdjustment = 1;
		goto doIncrStk;
	}

    case INST_INCR_ARRAY_STK_IMM:
    case INST_INCR_SCALAR_STK_IMM:
    case INST_INCR_STK_IMM:
	i = TclGetInt1AtPtr(pc+1);
	pcAdjustment = 2;
	    
    doIncrStk:
	if ((*pc == INST_INCR_ARRAY_STK_IMM) 
	        || (*pc == INST_INCR_ARRAY_STK)) {
	    part2 = TclGetString(stackPtr[stackTop]);
	    objPtr = stackPtr[stackTop - 1];
	    TRACE(("\"%.30s(%.30s)\" (by %ld) => ",
		    O2S(objPtr), part2, i));
	} else {
	    part2 = NULL;
	    objPtr = stackPtr[stackTop];
	    TRACE(("\"%.30s\" (by %ld) => ", O2S(objPtr), i));
	}
	part1 = TclGetString(objPtr);

	varPtr = TclObjLookupVar(interp, objPtr, part2, 
	        TCL_LEAVE_ERR_MSG, "read", 0, 1, &arrayPtr);
	if (varPtr == NULL) {
	    DECACHE_STACK_INFO();
	    Tcl_AddObjErrorInfo(interp,
	            "\n    (reading value of variable to increment)", -1);
	    CACHE_STACK_INFO();
	    TRACE_APPEND(("ERROR: %.30s\n", O2S(Tcl_GetObjResult(interp))));
	    result = TCL_ERROR;
	    goto checkForCatch;
	}
	cleanup = ((part2 == NULL)? 1 : 2);
	goto doIncrVar;

    case INST_INCR_ARRAY1_IMM:
	opnd = TclGetUInt1AtPtr(pc+1);
	i = TclGetInt1AtPtr(pc+2);
	pcAdjustment = 3;

    doIncrArray:
	part2 = TclGetString(stackPtr[stackTop]);
	arrayPtr = &(varFramePtr->compiledLocals[opnd]);
	part1 = arrayPtr->name;
	while (TclIsVarLink(arrayPtr)) {
	    arrayPtr = arrayPtr->value.linkPtr;
	}
	TRACE(("%u \"%.30s\" (by %ld) => ",
		    opnd, part2, i));
	varPtr = TclLookupArrayElement(interp, part1, part2, 
	        TCL_LEAVE_ERR_MSG, "read", 0, 1, arrayPtr);
	if (varPtr == NULL) {
	    TRACE_APPEND(("ERROR: %.30s\n", O2S(Tcl_GetObjResult(interp))));
	    result = TCL_ERROR;
	    goto checkForCatch;
	}
	cleanup = 1;
	goto doIncrVar;

    case INST_INCR_SCALAR1_IMM:
	opnd = TclGetUInt1AtPtr(pc+1);
	i = TclGetInt1AtPtr(pc+2);
	pcAdjustment = 3;

    doIncrScalar:
	varPtr = &(varFramePtr->compiledLocals[opnd]);
	part1 = varPtr->name;
	while (TclIsVarLink(varPtr)) {
	    varPtr = varPtr->value.linkPtr;
	}
	arrayPtr = NULL;
	part2 = NULL;
	cleanup = 0;
	TRACE(("%u %ld => ", opnd, i));


    doIncrVar:
	objPtr = varPtr->value.objPtr;
	if (TclIsVarScalar(varPtr)
	        && !TclIsVarUndefined(varPtr) 
	        && (varPtr->tracePtr == NULL)
	        && ((arrayPtr == NULL) 
		        || (arrayPtr->tracePtr == NULL))
	        && (objPtr->typePtr == &tclIntType)) {
	    /*
	     * No errors, no traces, the variable already has an
	     * integer value: inline processing.
	     */

	    i += objPtr->internalRep.longValue;
	    if (Tcl_IsShared(objPtr)) {
		objResultPtr = Tcl_NewLongObj(i);
		TclDecrRefCount(objPtr);
		Tcl_IncrRefCount(objResultPtr);
		varPtr->value.objPtr = objResultPtr;
	    } else {
		Tcl_SetLongObj(objPtr, i);
		objResultPtr = objPtr;
	    }
	    TRACE_APPEND(("%.30s\n", O2S(objResultPtr)));
	} else {
	    DECACHE_STACK_INFO();
	    objResultPtr = TclPtrIncrVar(interp, varPtr, arrayPtr, part1, 
                    part2, i, TCL_LEAVE_ERR_MSG);
	    CACHE_STACK_INFO();
	    if (objResultPtr == NULL) {
		TRACE_APPEND(("ERROR: %.30s\n", O2S(Tcl_GetObjResult(interp))));
		result = TCL_ERROR;
		goto checkForCatch;
	    }
	}
	TRACE_APPEND(("%.30s\n", O2S(objResultPtr)));
#ifndef TCL_COMPILE_DEBUG
	if (*(pc+pcAdjustment) == INST_POP) {
	    NEXT_INST_V((pcAdjustment+1), cleanup, 0);
	}
#endif
	NEXT_INST_V(pcAdjustment, cleanup, 1);
	    	    
    /*
     *     End of INST_INCR instructions.
     * ---------------------------------------------------------
     */


    case INST_JUMP1:
	opnd = TclGetInt1AtPtr(pc+1);
	TRACE(("%d => new pc %u\n", opnd,
	        (unsigned int)(pc + opnd - codePtr->codeStart)));
	NEXT_INST_F(opnd, 0, 0);

    case INST_JUMP4:
	opnd = TclGetInt4AtPtr(pc+1);
	TRACE(("%d => new pc %u\n", opnd,
	        (unsigned int)(pc + opnd - codePtr->codeStart)));
	NEXT_INST_F(opnd, 0, 0);

    case INST_JUMP_FALSE4:
	opnd = 5;                             /* TRUE */
	pcAdjustment = TclGetInt4AtPtr(pc+1); /* FALSE */
	goto doJumpTrue;

    case INST_JUMP_TRUE4:
	opnd = TclGetInt4AtPtr(pc+1);         /* TRUE */
	pcAdjustment = 5;                     /* FALSE */
	goto doJumpTrue;

    case INST_JUMP_FALSE1:
	opnd = 2;                             /* TRUE */
	pcAdjustment = TclGetInt1AtPtr(pc+1); /* FALSE */
	goto doJumpTrue;

    case INST_JUMP_TRUE1:
	opnd = TclGetInt1AtPtr(pc+1);          /* TRUE */
	pcAdjustment = 2;                      /* FALSE */
	    
    doJumpTrue:
	{
	    int b;
		
	    valuePtr = stackPtr[stackTop];
	    if (valuePtr->typePtr == &tclIntType) {
		b = (valuePtr->internalRep.longValue != 0);
	    } else if (valuePtr->typePtr == &tclDoubleType) {
		b = (valuePtr->internalRep.doubleValue != 0.0);
	    } else if (valuePtr->typePtr == &tclWideIntType) {
		TclGetWide(w,valuePtr);
		b = (w != W0);
	    } else {
		result = Tcl_GetBooleanFromObj(interp, valuePtr, &b);
		if (result != TCL_OK) {
		    TRACE_WITH_OBJ(("%d => ERROR: ", opnd), Tcl_GetObjResult(interp));
		    goto checkForCatch;
		}
	    }
#ifndef TCL_COMPILE_DEBUG
	    NEXT_INST_F((b? opnd : pcAdjustment), 1, 0);
#else
	    if (b) {
		if ((*pc == INST_JUMP_TRUE1) || (*pc == INST_JUMP_TRUE1)) {
		    TRACE(("%d => %.20s true, new pc %u\n", opnd, O2S(valuePtr),
		            (unsigned int)(pc+opnd - codePtr->codeStart)));
		} else {
		    TRACE(("%d => %.20s true\n", pcAdjustment, O2S(valuePtr)));
		}
		NEXT_INST_F(opnd, 1, 0);
	    } else {
		if ((*pc == INST_JUMP_TRUE1) || (*pc == INST_JUMP_TRUE1)) {
		    TRACE(("%d => %.20s false\n", opnd, O2S(valuePtr)));
		} else {
		    opnd = pcAdjustment;
		    TRACE(("%d => %.20s false, new pc %u\n", opnd, O2S(valuePtr),
		            (unsigned int)(pc + opnd - codePtr->codeStart)));
		}
		NEXT_INST_F(pcAdjustment, 1, 0);
	    }
#endif
	}
	    	    
    case INST_LOR:
    case INST_LAND:
    {
	/*
	 * Operands must be boolean or numeric. No int->double
	 * conversions are performed.
	 */
		
	int i1, i2;
	int iResult;
	char *s;
	Tcl_ObjType *t1Ptr, *t2Ptr;

	value2Ptr = stackPtr[stackTop];
	valuePtr  = stackPtr[stackTop - 1];;
	t1Ptr = valuePtr->typePtr;
	t2Ptr = value2Ptr->typePtr;

	if ((t1Ptr == &tclIntType) || (t1Ptr == &tclBooleanType)) {
	    i1 = (valuePtr->internalRep.longValue != 0);
	} else if (t1Ptr == &tclWideIntType) {
	    TclGetWide(w,valuePtr);
	    i1 = (w != W0);
	} else if (t1Ptr == &tclDoubleType) {
	    i1 = (valuePtr->internalRep.doubleValue != 0.0);
	} else {
	    s = Tcl_GetStringFromObj(valuePtr, &length);
	    if (TclLooksLikeInt(s, length)) {
		GET_WIDE_OR_INT(result, valuePtr, i, w);
		if (valuePtr->typePtr == &tclIntType) {
		    i1 = (i != 0);
		} else {
		    i1 = (w != W0);
		}
	    } else {
		result = Tcl_GetBooleanFromObj((Tcl_Interp *) NULL,
					       valuePtr, &i1);
		i1 = (i1 != 0);
	    }
	    if (result != TCL_OK) {
		TRACE(("\"%.20s\" => ILLEGAL TYPE %s \n", O2S(valuePtr),
		        (t1Ptr? t1Ptr->name : "null")));
		DECACHE_STACK_INFO();
		IllegalExprOperandType(interp, pc, valuePtr);
		CACHE_STACK_INFO();
		goto checkForCatch;
	    }
	}
		
	if ((t2Ptr == &tclIntType) || (t2Ptr == &tclBooleanType)) {
	    i2 = (value2Ptr->internalRep.longValue != 0);
	} else if (t2Ptr == &tclWideIntType) {
	    TclGetWide(w,value2Ptr);
	    i2 = (w != W0);
	} else if (t2Ptr == &tclDoubleType) {
	    i2 = (value2Ptr->internalRep.doubleValue != 0.0);
	} else {
	    s = Tcl_GetStringFromObj(value2Ptr, &length);
	    if (TclLooksLikeInt(s, length)) {
		GET_WIDE_OR_INT(result, value2Ptr, i, w);
		if (value2Ptr->typePtr == &tclIntType) {
		    i2 = (i != 0);
		} else {
		    i2 = (w != W0);
		}
	    } else {
		result = Tcl_GetBooleanFromObj((Tcl_Interp *) NULL, value2Ptr, &i2);
	    }
	    if (result != TCL_OK) {
		TRACE(("\"%.20s\" => ILLEGAL TYPE %s \n", O2S(value2Ptr),
		        (t2Ptr? t2Ptr->name : "null")));
		DECACHE_STACK_INFO();
		IllegalExprOperandType(interp, pc, value2Ptr);
		CACHE_STACK_INFO();
		goto checkForCatch;
	    }
	}

	/*
	 * Reuse the valuePtr object already on stack if possible.
	 */
	
	if (*pc == INST_LOR) {
	    iResult = (i1 || i2);
	} else {
	    iResult = (i1 && i2);
	}
	if (Tcl_IsShared(valuePtr)) {
	    objResultPtr = Tcl_NewLongObj(iResult);
	    TRACE(("%.20s %.20s => %d\n", O2S(valuePtr), O2S(value2Ptr), iResult));
	    NEXT_INST_F(1, 2, 1);
	} else {	/* reuse the valuePtr object */
	    TRACE(("%.20s %.20s => %d\n", O2S(valuePtr), O2S(value2Ptr), iResult));
	    Tcl_SetLongObj(valuePtr, iResult);
	    NEXT_INST_F(1, 1, 0);
	}
    }

    /*
     * ---------------------------------------------------------
     *     Start of INST_LIST and related instructions.
     */

    case INST_LIST:
	/*
	 * Pop the opnd (objc) top stack elements into a new list obj
	 * and then decrement their ref counts. 
	 */

	opnd = TclGetUInt4AtPtr(pc+1);
	objResultPtr = Tcl_NewListObj(opnd, &(stackPtr[stackTop - (opnd-1)]));
	TRACE_WITH_OBJ(("%u => ", opnd), objResultPtr);
	NEXT_INST_V(5, opnd, 1);

    case INST_LIST_LENGTH:
	valuePtr = stackPtr[stackTop];

	result = Tcl_ListObjLength(interp, valuePtr, &length);
	if (result != TCL_OK) {
	    TRACE_WITH_OBJ(("%.30s => ERROR: ", O2S(valuePtr)),
	            Tcl_GetObjResult(interp));
	    goto checkForCatch;
	}
	objResultPtr = Tcl_NewIntObj(length);
	TRACE(("%.20s => %d\n", O2S(valuePtr), length));
	NEXT_INST_F(1, 1, 1);
	    
    case INST_LIST_INDEX:
	/*** lindex with objc == 3 ***/
		
	/*
	 * Pop the two operands
	 */
	value2Ptr = stackPtr[stackTop];
	valuePtr  = stackPtr[stackTop- 1];

	/*
	 * Extract the desired list element
	 */
	objResultPtr = TclLindexList(interp, valuePtr, value2Ptr);
	if (objResultPtr == NULL) {
	    TRACE_WITH_OBJ(("%.30s %.30s => ERROR: ", O2S(valuePtr), O2S(value2Ptr)),
	            Tcl_GetObjResult(interp));
	    result = TCL_ERROR;
	    goto checkForCatch;
	}

	/*
	 * Stash the list element on the stack
	 */
	TRACE(("%.20s %.20s => %s\n",
	        O2S(valuePtr), O2S(value2Ptr), O2S(objResultPtr)));
	NEXT_INST_F(1, 2, -1); /* already has the correct refCount */

    case INST_LIST_INDEX_MULTI:
    {
	/*
	 * 'lindex' with multiple index args:
	 *
	 * Determine the count of index args.
	 */

	int numIdx;

	opnd = TclGetUInt4AtPtr(pc+1);
	numIdx = opnd-1;

	/*
	 * Do the 'lindex' operation.
	 */
	objResultPtr = TclLindexFlat(interp, stackPtr[stackTop - numIdx],
	        numIdx, stackPtr + stackTop - numIdx + 1);

	/*
	 * Check for errors
	 */
	if (objResultPtr == NULL) {
	    TRACE_WITH_OBJ(("%d => ERROR: ", opnd), Tcl_GetObjResult(interp));
	    result = TCL_ERROR;
	    goto checkForCatch;
	}

	/*
	 * Set result
	 */
	TRACE(("%d => %s\n", opnd, O2S(objResultPtr)));
	NEXT_INST_V(5, opnd, -1);
    }

    case INST_LSET_FLAT:
    {
	/*
	 * Lset with 3, 5, or more args.  Get the number
	 * of index args.
	 */
	int numIdx;

	opnd = TclGetUInt4AtPtr( pc + 1 );
	numIdx = opnd - 2;

	/*
	 * Get the old value of variable, and remove the stack ref.
	 * This is safe because the variable still references the
	 * object; the ref count will never go zero here.
	 */
	value2Ptr = POP_OBJECT();
	TclDecrRefCount(value2Ptr); /* This one should be done here */

	/*
	 * Get the new element value.
	 */
	valuePtr = stackPtr[stackTop];

	/*
	 * Compute the new variable value
	 */
	objResultPtr = TclLsetFlat(interp, value2Ptr, numIdx,
	        stackPtr + stackTop - numIdx, valuePtr);


	/*
	 * Check for errors
	 */
	if (objResultPtr == NULL) {
	    TRACE_WITH_OBJ(("%d => ERROR: ", opnd), Tcl_GetObjResult(interp));
	    result = TCL_ERROR;
	    goto checkForCatch;
	}

	/*
	 * Set result
	 */
	TRACE(("%d => %s\n", opnd, O2S(objResultPtr)));
	NEXT_INST_V(5, (numIdx+1), -1);
    }

    case INST_LSET_LIST:
	/*
	 * 'lset' with 4 args.
	 *
	 * Get the old value of variable, and remove the stack ref.
	 * This is safe because the variable still references the
	 * object; the ref count will never go zero here.
	 */
	objPtr = POP_OBJECT(); 
	TclDecrRefCount(objPtr); /* This one should be done here */
	
	/*
	 * Get the new element value, and the index list
	 */
	valuePtr = stackPtr[stackTop];
	value2Ptr = stackPtr[stackTop - 1];
	
	/*
	 * Compute the new variable value
	 */
	objResultPtr = TclLsetList(interp, objPtr, value2Ptr, valuePtr);

	/*
	 * Check for errors
	 */
	if (objResultPtr == NULL) {
	    TRACE_WITH_OBJ(("\"%.30s\" => ERROR: ", O2S(value2Ptr)),
	            Tcl_GetObjResult(interp));
	    result = TCL_ERROR;
	    goto checkForCatch;
	}

	/*
	 * Set result
	 */
	TRACE(("=> %s\n", O2S(objResultPtr)));
	NEXT_INST_F(1, 2, -1);

    /*
     *     End of INST_LIST and related instructions.
     * ---------------------------------------------------------
     */

    case INST_STR_EQ:
    case INST_STR_NEQ:
    {
	/*
	 * String (in)equality check
	 */
	int iResult;

	value2Ptr = stackPtr[stackTop];
	valuePtr = stackPtr[stackTop - 1];

	if (valuePtr == value2Ptr) {
	    /*
	     * On the off-chance that the objects are the same,
	     * we don't really have to think hard about equality.
	     */
	    iResult = (*pc == INST_STR_EQ);
	} else {
	    char *s1, *s2;
	    int s1len, s2len;

	    s1 = Tcl_GetStringFromObj(valuePtr, &s1len);
	    s2 = Tcl_GetStringFromObj(value2Ptr, &s2len);
	    if (s1len == s2len) {
		/*
		 * We only need to check (in)equality when
		 * we have equal length strings.
		 */
		if (*pc == INST_STR_NEQ) {
		    iResult = (strcmp(s1, s2) != 0);
		} else {
		    /* INST_STR_EQ */
		    iResult = (strcmp(s1, s2) == 0);
		}
	    } else {
		iResult = (*pc == INST_STR_NEQ);
	    }
	}

	TRACE(("%.20s %.20s => %d\n", O2S(valuePtr), O2S(value2Ptr), iResult));

	/*
	 * Peep-hole optimisation: if you're about to jump, do jump
	 * from here.
	 */

	pc++;
#ifndef TCL_COMPILE_DEBUG
	switch (*pc) {
	    case INST_JUMP_FALSE1:
		NEXT_INST_F((iResult? 2 : TclGetInt1AtPtr(pc+1)), 2, 0);
	    case INST_JUMP_TRUE1:
		NEXT_INST_F((iResult? TclGetInt1AtPtr(pc+1) : 2), 2, 0);
	    case INST_JUMP_FALSE4:
		NEXT_INST_F((iResult? 5 : TclGetInt4AtPtr(pc+1)), 2, 0);
	    case INST_JUMP_TRUE4:
		NEXT_INST_F((iResult? TclGetInt4AtPtr(pc+1) : 5), 2, 0);
	}
#endif
	objResultPtr = Tcl_NewIntObj(iResult);
	NEXT_INST_F(0, 2, 1);
    }

    case INST_STR_CMP:
    {
	/*
	 * String compare
	 */
	CONST char *s1, *s2;
	int s1len, s2len, iResult;

	value2Ptr = stackPtr[stackTop];
	valuePtr = stackPtr[stackTop - 1];

	/*
	 * The comparison function should compare up to the
	 * minimum byte length only.
	 */
	if (valuePtr == value2Ptr) {
	    /*
	     * In the pure equality case, set lengths too for
	     * the checks below (or we could goto beyond it).
	     */
	    iResult = s1len = s2len = 0;
	} else if ((valuePtr->typePtr == &tclByteArrayType)
	        && (value2Ptr->typePtr == &tclByteArrayType)) {
	    s1 = (char *) Tcl_GetByteArrayFromObj(valuePtr, &s1len);
	    s2 = (char *) Tcl_GetByteArrayFromObj(value2Ptr, &s2len);
	    iResult = memcmp(s1, s2, 
	            (size_t) ((s1len < s2len) ? s1len : s2len));
	} else if (((valuePtr->typePtr == &tclStringType)
	        && (value2Ptr->typePtr == &tclStringType))) {
	    /*
	     * Do a unicode-specific comparison if both of the args are of
	     * String type.  If the char length == byte length, we can do a
	     * memcmp.  In benchmark testing this proved the most efficient
	     * check between the unicode and string comparison operations.
	     */

	    s1len = Tcl_GetCharLength(valuePtr);
	    s2len = Tcl_GetCharLength(value2Ptr);
	    if ((s1len == valuePtr->length) && (s2len == value2Ptr->length)) {
		iResult = memcmp(valuePtr->bytes, value2Ptr->bytes,
			(unsigned) ((s1len < s2len) ? s1len : s2len));
	    } else {
		iResult = TclUniCharNcmp(Tcl_GetUnicode(valuePtr),
			Tcl_GetUnicode(value2Ptr),
			(unsigned) ((s1len < s2len) ? s1len : s2len));
	    }
	} else {
	    /*
	     * We can't do a simple memcmp in order to handle the
	     * special Tcl \xC0\x80 null encoding for utf-8.
	     */
	    s1 = Tcl_GetStringFromObj(valuePtr, &s1len);
	    s2 = Tcl_GetStringFromObj(value2Ptr, &s2len);
	    iResult = TclpUtfNcmp2(s1, s2,
	            (size_t) ((s1len < s2len) ? s1len : s2len));
	}

	/*
	 * Make sure only -1,0,1 is returned
	 */
	if (iResult == 0) {
	    iResult = s1len - s2len;
	}
	if (iResult < 0) {
	    iResult = -1;
	} else if (iResult > 0) {
	    iResult = 1;
	}

	objResultPtr = Tcl_NewIntObj(iResult);
	TRACE(("%.20s %.20s => %d\n", O2S(valuePtr), O2S(value2Ptr), iResult));
	NEXT_INST_F(1, 2, 1);
    }

    case INST_STR_LEN:
    {
	int length1;
		 
	valuePtr = stackPtr[stackTop];

	if (valuePtr->typePtr == &tclByteArrayType) {
	    (void) Tcl_GetByteArrayFromObj(valuePtr, &length1);
	} else {
	    length1 = Tcl_GetCharLength(valuePtr);
	}
	objResultPtr = Tcl_NewIntObj(length1);
	TRACE(("%.20s => %d\n", O2S(valuePtr), length1));
	NEXT_INST_F(1, 1, 1);
    }
	    
    case INST_STR_INDEX:
    {
	/*
	 * String compare
	 */
	int index;
	bytes = NULL; /* lint */

	value2Ptr = stackPtr[stackTop];
	valuePtr = stackPtr[stackTop - 1];

	/*
	 * If we have a ByteArray object, avoid indexing in the
	 * Utf string since the byte array contains one byte per
	 * character.  Otherwise, use the Unicode string rep to
	 * get the index'th char.
	 */

	if (valuePtr->typePtr == &tclByteArrayType) {
	    bytes = (char *)Tcl_GetByteArrayFromObj(valuePtr, &length);
	} else {
	    /*
	     * Get Unicode char length to calulate what 'end' means.
	     */
	    length = Tcl_GetCharLength(valuePtr);
	}

	result = TclGetIntForIndex(interp, value2Ptr, length - 1, &index);
	if (result != TCL_OK) {
	    goto checkForCatch;
	}

	if ((index >= 0) && (index < length)) {
	    if (valuePtr->typePtr == &tclByteArrayType) {
		objResultPtr = Tcl_NewByteArrayObj((unsigned char *)
		        (&bytes[index]), 1);
	    } else if (valuePtr->bytes && length == valuePtr->length) {
		objResultPtr = Tcl_NewStringObj((CONST char *)
		        (&valuePtr->bytes[index]), 1);
	    } else {
		char buf[TCL_UTF_MAX];
		Tcl_UniChar ch;

		ch = Tcl_GetUniChar(valuePtr, index);
		/*
		 * This could be:
		 * Tcl_NewUnicodeObj((CONST Tcl_UniChar *)&ch, 1)
		 * but creating the object as a string seems to be
		 * faster in practical use.
		 */
		length = Tcl_UniCharToUtf(ch, buf);
		objResultPtr = Tcl_NewStringObj(buf, length);
	    }
	} else {
	    TclNewObj(objResultPtr);
	}

	TRACE(("%.20s %.20s => %s\n", O2S(valuePtr), O2S(value2Ptr), 
	        O2S(objResultPtr)));
	NEXT_INST_F(1, 2, 1);
    }

    case INST_STR_MATCH:
    {
	int nocase, match;

	nocase    = TclGetInt1AtPtr(pc+1);
	valuePtr  = stackPtr[stackTop];	        /* String */
	value2Ptr = stackPtr[stackTop - 1];	/* Pattern */

	/*
	 * Check that at least one of the objects is Unicode before
	 * promoting both.
	 */

	if ((valuePtr->typePtr == &tclStringType)
	        || (value2Ptr->typePtr == &tclStringType)) {
	    Tcl_UniChar *ustring1, *ustring2;
	    int length1, length2;

	    ustring1 = Tcl_GetUnicodeFromObj(valuePtr, &length1);
	    ustring2 = Tcl_GetUnicodeFromObj(value2Ptr, &length2);
	    match = TclUniCharMatch(ustring1, length1, ustring2, length2,
		    nocase);
	} else {
	    match = Tcl_StringCaseMatch(TclGetString(valuePtr),
		    TclGetString(value2Ptr), nocase);
	}

	/*
	 * Reuse value2Ptr object already on stack if possible.
	 * Adjustment is 2 due to the nocase byte
	 */

	TRACE(("%.20s %.20s => %d\n", O2S(valuePtr), O2S(value2Ptr), match));
	if (Tcl_IsShared(value2Ptr)) {
	    objResultPtr = Tcl_NewIntObj(match);
	    NEXT_INST_F(2, 2, 1);
	} else {	/* reuse the valuePtr object */
	    Tcl_SetIntObj(value2Ptr, match);
	    NEXT_INST_F(2, 1, 0);
	}
    }

    case INST_EQ:
    case INST_NEQ:
    case INST_LT:
    case INST_GT:
    case INST_LE:
    case INST_GE:
    {
	/*
	 * Any type is allowed but the two operands must have the
	 * same type. We will compute value op value2.
	 */

	Tcl_ObjType *t1Ptr, *t2Ptr;
	char *s1 = NULL;	/* Init. avoids compiler warning. */
	char *s2 = NULL;	/* Init. avoids compiler warning. */
	long i2 = 0;		/* Init. avoids compiler warning. */
	double d1 = 0.0;	/* Init. avoids compiler warning. */
	double d2 = 0.0;	/* Init. avoids compiler warning. */
	long iResult = 0;	/* Init. avoids compiler warning. */

	value2Ptr = stackPtr[stackTop];
	valuePtr  = stackPtr[stackTop - 1];

	if (valuePtr == value2Ptr) {
	    /*
	     * Optimize the equal object case.
	     */
	    switch (*pc) {
	        case INST_EQ:
	        case INST_LE:
	        case INST_GE:
		    iResult = 1;
		    break;
	        case INST_NEQ:
	        case INST_LT:
	        case INST_GT:
		    iResult = 0;
		    break;
	    }
	    goto foundResult;
	}

	t1Ptr = valuePtr->typePtr;
	t2Ptr = value2Ptr->typePtr;

	/*
	 * We only want to coerce numeric validation if neither type
	 * is NULL.  A NULL type means the arg is essentially an empty
	 * object ("", {} or [list]).
	 */
	if (!(     (!t1Ptr && !valuePtr->bytes)
	        || (valuePtr->bytes && !valuePtr->length)
		   || (!t2Ptr && !value2Ptr->bytes)
		   || (value2Ptr->bytes && !value2Ptr->length))) {
	    if (!IS_NUMERIC_TYPE(t1Ptr)) {
		s1 = Tcl_GetStringFromObj(valuePtr, &length);
		if (TclLooksLikeInt(s1, length)) {
		    GET_WIDE_OR_INT(iResult, valuePtr, i, w);
		} else {
		    (void) Tcl_GetDoubleFromObj((Tcl_Interp *) NULL, 
		            valuePtr, &d1);
		}
		t1Ptr = valuePtr->typePtr;
	    }
	    if (!IS_NUMERIC_TYPE(t2Ptr)) {
		s2 = Tcl_GetStringFromObj(value2Ptr, &length);
		if (TclLooksLikeInt(s2, length)) {
		    GET_WIDE_OR_INT(iResult, value2Ptr, i2, w);
		} else {
		    (void) Tcl_GetDoubleFromObj((Tcl_Interp *) NULL,
		            value2Ptr, &d2);
		}
		t2Ptr = value2Ptr->typePtr;
	    }
	}
	if (!IS_NUMERIC_TYPE(t1Ptr) || !IS_NUMERIC_TYPE(t2Ptr)) {
	    /*
	     * One operand is not numeric. Compare as strings.  NOTE:
	     * strcmp is not correct for \x00 < \x01, but that is
	     * unlikely to occur here.  We could use the TclUtfNCmp2
	     * to handle this.
	     */
	    int s1len, s2len;
	    s1 = Tcl_GetStringFromObj(valuePtr, &s1len);
	    s2 = Tcl_GetStringFromObj(value2Ptr, &s2len);
	    switch (*pc) {
	        case INST_EQ:
		    if (s1len == s2len) {
			iResult = (strcmp(s1, s2) == 0);
		    } else {
			iResult = 0;
		    }
		    break;
	        case INST_NEQ:
		    if (s1len == s2len) {
			iResult = (strcmp(s1, s2) != 0);
		    } else {
			iResult = 1;
		    }
		    break;
	        case INST_LT:
		    iResult = (strcmp(s1, s2) < 0);
		    break;
	        case INST_GT:
		    iResult = (strcmp(s1, s2) > 0);
		    break;
	        case INST_LE:
		    iResult = (strcmp(s1, s2) <= 0);
		    break;
	        case INST_GE:
		    iResult = (strcmp(s1, s2) >= 0);
		    break;
	    }
	} else if ((t1Ptr == &tclDoubleType)
		   || (t2Ptr == &tclDoubleType)) {
	    /*
	     * Compare as doubles.
	     */
	    if (t1Ptr == &tclDoubleType) {
		d1 = valuePtr->internalRep.doubleValue;
		GET_DOUBLE_VALUE(d2, value2Ptr, t2Ptr);
	    } else {	/* t1Ptr is integer, t2Ptr is double */
		GET_DOUBLE_VALUE(d1, valuePtr, t1Ptr);
		d2 = value2Ptr->internalRep.doubleValue;
	    }
	    switch (*pc) {
	        case INST_EQ:
		    iResult = d1 == d2;
		    break;
	        case INST_NEQ:
		    iResult = d1 != d2;
		    break;
	        case INST_LT:
		    iResult = d1 < d2;
		    break;
	        case INST_GT:
		    iResult = d1 > d2;
		    break;
	        case INST_LE:
		    iResult = d1 <= d2;
		    break;
	        case INST_GE:
		    iResult = d1 >= d2;
		    break;
	    }
	} else if ((t1Ptr == &tclWideIntType)
	        || (t2Ptr == &tclWideIntType)) {
	    Tcl_WideInt w2;
	    /*
	     * Compare as wide ints (neither are doubles)
	     */
	    if (t1Ptr == &tclIntType) {
		w  = Tcl_LongAsWide(valuePtr->internalRep.longValue);
		TclGetWide(w2,value2Ptr);
	    } else if (t2Ptr == &tclIntType) {
		TclGetWide(w,valuePtr);
		w2 = Tcl_LongAsWide(value2Ptr->internalRep.longValue);
	    } else {
		TclGetWide(w,valuePtr);
		TclGetWide(w2,value2Ptr);
	    }
	    switch (*pc) {
	        case INST_EQ:
		    iResult = w == w2;
		    break;
	        case INST_NEQ:
		    iResult = w != w2;
		    break;
	        case INST_LT:
		    iResult = w < w2;
		    break;
	        case INST_GT:
		    iResult = w > w2;
		    break;
	        case INST_LE:
		    iResult = w <= w2;
		    break;
	        case INST_GE:
		    iResult = w >= w2;
		    break;
	    }
	} else {
	    /*
	     * Compare as ints.
	     */
	    i  = valuePtr->internalRep.longValue;
	    i2 = value2Ptr->internalRep.longValue;
	    switch (*pc) {
	        case INST_EQ:
		    iResult = i == i2;
		    break;
	        case INST_NEQ:
		    iResult = i != i2;
		    break;
	        case INST_LT:
		    iResult = i < i2;
		    break;
	        case INST_GT:
		    iResult = i > i2;
		    break;
	        case INST_LE:
		    iResult = i <= i2;
		    break;
	        case INST_GE:
		    iResult = i >= i2;
		    break;
	    }
	}

    foundResult:
	TRACE(("%.20s %.20s => %ld\n", O2S(valuePtr), O2S(value2Ptr), iResult));

	/*
	 * Peep-hole optimisation: if you're about to jump, do jump
	 * from here.
	 */

	pc++;
#ifndef TCL_COMPILE_DEBUG
	switch (*pc) {
	    case INST_JUMP_FALSE1:
		NEXT_INST_F((iResult? 2 : TclGetInt1AtPtr(pc+1)), 2, 0);
	    case INST_JUMP_TRUE1:
		NEXT_INST_F((iResult? TclGetInt1AtPtr(pc+1) : 2), 2, 0);
	    case INST_JUMP_FALSE4:
		NEXT_INST_F((iResult? 5 : TclGetInt4AtPtr(pc+1)), 2, 0);
	    case INST_JUMP_TRUE4:
		NEXT_INST_F((iResult? TclGetInt4AtPtr(pc+1) : 5), 2, 0);
	}
#endif
	objResultPtr = Tcl_NewIntObj(iResult);
	NEXT_INST_F(0, 2, 1);
    }

    case INST_MOD:
    case INST_LSHIFT:
    case INST_RSHIFT:
    case INST_BITOR:
    case INST_BITXOR:
    case INST_BITAND:
    {
	/*
	 * Only integers are allowed. We compute value op value2.
	 */

	long i2 = 0, rem, negative;
	long iResult = 0; /* Init. avoids compiler warning. */
	Tcl_WideInt w2, wResult = W0;
	int doWide = 0;

	value2Ptr = stackPtr[stackTop];
	valuePtr  = stackPtr[stackTop - 1]; 
	if (valuePtr->typePtr == &tclIntType) {
	    i = valuePtr->internalRep.longValue;
	} else if (valuePtr->typePtr == &tclWideIntType) {
	    TclGetWide(w,valuePtr);
	} else {	/* try to convert to int */
	    REQUIRE_WIDE_OR_INT(result, valuePtr, i, w);
	    if (result != TCL_OK) {
		TRACE(("%.20s %.20s => ILLEGAL 1st TYPE %s\n",
		        O2S(valuePtr), O2S(value2Ptr), 
		        (valuePtr->typePtr? 
			     valuePtr->typePtr->name : "null")));
		DECACHE_STACK_INFO();
		IllegalExprOperandType(interp, pc, valuePtr);
		CACHE_STACK_INFO();
		goto checkForCatch;
	    }
	}
	if (value2Ptr->typePtr == &tclIntType) {
	    i2 = value2Ptr->internalRep.longValue;
	} else if (value2Ptr->typePtr == &tclWideIntType) {
	    TclGetWide(w2,value2Ptr);
	} else {
	    REQUIRE_WIDE_OR_INT(result, value2Ptr, i2, w2);
	    if (result != TCL_OK) {
		TRACE(("%.20s %.20s => ILLEGAL 2nd TYPE %s\n",
		        O2S(valuePtr), O2S(value2Ptr),
		        (value2Ptr->typePtr?
			    value2Ptr->typePtr->name : "null")));
		DECACHE_STACK_INFO();
		IllegalExprOperandType(interp, pc, value2Ptr);
		CACHE_STACK_INFO();
		goto checkForCatch;
	    }
	}

	switch (*pc) {
	case INST_MOD:
	    /*
	     * This code is tricky: C doesn't guarantee much about
	     * the quotient or remainder, but Tcl does. The
	     * remainder always has the same sign as the divisor and
	     * a smaller absolute value.
	     */
	    if (value2Ptr->typePtr == &tclWideIntType && w2 == W0) {
		if (valuePtr->typePtr == &tclIntType) {
		    TRACE(("%ld "LLD" => DIVIDE BY ZERO\n", i, w2));
		} else {
		    TRACE((LLD" "LLD" => DIVIDE BY ZERO\n", w, w2));
		}
		goto divideByZero;
	    }
	    if (value2Ptr->typePtr == &tclIntType && i2 == 0) {
		if (valuePtr->typePtr == &tclIntType) {
		    TRACE(("%ld %ld => DIVIDE BY ZERO\n", i, i2));
		} else {
		    TRACE((LLD" %ld => DIVIDE BY ZERO\n", w, i2));
		}
		goto divideByZero;
	    }
	    negative = 0;
	    if (valuePtr->typePtr == &tclWideIntType
		|| value2Ptr->typePtr == &tclWideIntType) {
		Tcl_WideInt wRemainder;
		/*
		 * Promote to wide
		 */
		if (valuePtr->typePtr == &tclIntType) {
		    w = Tcl_LongAsWide(i);
		} else if (value2Ptr->typePtr == &tclIntType) {
		    w2 = Tcl_LongAsWide(i2);
		}
		if (w2 < 0) {
		    w2 = -w2;
		    w = -w;
		    negative = 1;
		}
		wRemainder  = w % w2;
		if (wRemainder < 0) {
		    wRemainder += w2;
		}
		if (negative) {
		    wRemainder = -wRemainder;
		}
		wResult = wRemainder;
		doWide = 1;
		break;
	    }
	    if (i2 < 0) {
		i2 = -i2;
		i = -i;
		negative = 1;
	    }
	    rem  = i % i2;
	    if (rem < 0) {
		rem += i2;
	    }
	    if (negative) {
		rem = -rem;
	    }
	    iResult = rem;
	    break;
	case INST_LSHIFT:
	    /*
	     * Shifts are never usefully 64-bits wide!
	     */
	    FORCE_LONG(value2Ptr, i2, w2);
	    if (valuePtr->typePtr == &tclWideIntType) {
#ifdef TCL_COMPILE_DEBUG
		w2 = Tcl_LongAsWide(i2);
#endif /* TCL_COMPILE_DEBUG */
		wResult = w << i2;
		doWide = 1;
		break;
	    }
	    iResult = i << i2;
	    break;
	case INST_RSHIFT:
	    /*
	     * The following code is a bit tricky: it ensures that
	     * right shifts propagate the sign bit even on machines
	     * where ">>" won't do it by default.
	     */
	    /*
	     * Shifts are never usefully 64-bits wide!
	     */
	    FORCE_LONG(value2Ptr, i2, w2);
	    if (valuePtr->typePtr == &tclWideIntType) {
#ifdef TCL_COMPILE_DEBUG
		w2 = Tcl_LongAsWide(i2);
#endif /* TCL_COMPILE_DEBUG */
		if (w < 0) {
		    wResult = ~((~w) >> i2);
		} else {
		    wResult = w >> i2;
		}
		doWide = 1;
		break;
	    }
	    if (i < 0) {
		iResult = ~((~i) >> i2);
	    } else {
		iResult = i >> i2;
	    }
	    break;
	case INST_BITOR:
	    if (valuePtr->typePtr == &tclWideIntType
		|| value2Ptr->typePtr == &tclWideIntType) {
		/*
		 * Promote to wide
		 */
		if (valuePtr->typePtr == &tclIntType) {
		    w = Tcl_LongAsWide(i);
		} else if (value2Ptr->typePtr == &tclIntType) {
		    w2 = Tcl_LongAsWide(i2);
		}
		wResult = w | w2;
		doWide = 1;
		break;
	    }
	    iResult = i | i2;
	    break;
	case INST_BITXOR:
	    if (valuePtr->typePtr == &tclWideIntType
		|| value2Ptr->typePtr == &tclWideIntType) {
		/*
		 * Promote to wide
		 */
		if (valuePtr->typePtr == &tclIntType) {
		    w = Tcl_LongAsWide(i);
		} else if (value2Ptr->typePtr == &tclIntType) {
		    w2 = Tcl_LongAsWide(i2);
		}
		wResult = w ^ w2;
		doWide = 1;
		break;
	    }
	    iResult = i ^ i2;
	    break;
	case INST_BITAND:
	    if (valuePtr->typePtr == &tclWideIntType
		|| value2Ptr->typePtr == &tclWideIntType) {
		/*
		 * Promote to wide
		 */
		if (valuePtr->typePtr == &tclIntType) {
		    w = Tcl_LongAsWide(i);
		} else if (value2Ptr->typePtr == &tclIntType) {
		    w2 = Tcl_LongAsWide(i2);
		}
		wResult = w & w2;
		doWide = 1;
		break;
	    }
	    iResult = i & i2;
	    break;
	}

	/*
	 * Reuse the valuePtr object already on stack if possible.
	 */
		
	if (Tcl_IsShared(valuePtr)) {
	    if (doWide) {
		objResultPtr = Tcl_NewWideIntObj(wResult);
		TRACE((LLD" "LLD" => "LLD"\n", w, w2, wResult));
	    } else {
		objResultPtr = Tcl_NewLongObj(iResult);
		TRACE(("%ld %ld => %ld\n", i, i2, iResult));
	    }
	    NEXT_INST_F(1, 2, 1);
	} else {	/* reuse the valuePtr object */
	    if (doWide) {
		TRACE((LLD" "LLD" => "LLD"\n", w, w2, wResult));
		Tcl_SetWideIntObj(valuePtr, wResult);
	    } else {
		TRACE(("%ld %ld => %ld\n", i, i2, iResult));
		Tcl_SetLongObj(valuePtr, iResult);
	    }
	    NEXT_INST_F(1, 1, 0);
	}
    }

    case INST_ADD:
    case INST_SUB:
    case INST_MULT:
    case INST_DIV:
    {
	/*
	 * Operands must be numeric and ints get converted to floats
	 * if necessary. We compute value op value2.
	 */

	Tcl_ObjType *t1Ptr, *t2Ptr;
	long i2 = 0, quot, rem;	/* Init. avoids compiler warning. */
	double d1, d2;
	long iResult = 0;	/* Init. avoids compiler warning. */
	double dResult = 0.0;	/* Init. avoids compiler warning. */
	int doDouble = 0;	/* 1 if doing floating arithmetic */
	Tcl_WideInt w2, wquot, wrem;
	Tcl_WideInt wResult = W0; /* Init. avoids compiler warning. */
	int doWide = 0;		/* 1 if doing wide arithmetic. */

	value2Ptr = stackPtr[stackTop];
	valuePtr  = stackPtr[stackTop - 1];
	t1Ptr = valuePtr->typePtr;
	t2Ptr = value2Ptr->typePtr;
		
	if (t1Ptr == &tclIntType) {
	    i = valuePtr->internalRep.longValue;
	} else if (t1Ptr == &tclWideIntType) {
	    TclGetWide(w,valuePtr);
	} else if ((t1Ptr == &tclDoubleType)
		   && (valuePtr->bytes == NULL)) {
	    /*
	     * We can only use the internal rep directly if there is
	     * no string rep.  Otherwise the string rep might actually
	     * look like an integer, which is preferred.
	     */

	    d1 = valuePtr->internalRep.doubleValue;
	} else {
	    char *s = Tcl_GetStringFromObj(valuePtr, &length);
	    if (TclLooksLikeInt(s, length)) {
		GET_WIDE_OR_INT(result, valuePtr, i, w);
	    } else {
		result = Tcl_GetDoubleFromObj((Tcl_Interp *) NULL,
					      valuePtr, &d1);
	    }
	    if (result != TCL_OK) {
		TRACE(("%.20s %.20s => ILLEGAL 1st TYPE %s\n",
		        s, O2S(valuePtr),
		        (valuePtr->typePtr?
			    valuePtr->typePtr->name : "null")));
		DECACHE_STACK_INFO();
		IllegalExprOperandType(interp, pc, valuePtr);
		CACHE_STACK_INFO();
		goto checkForCatch;
	    }
	    t1Ptr = valuePtr->typePtr;
	}

	if (t2Ptr == &tclIntType) {
	    i2 = value2Ptr->internalRep.longValue;
	} else if (t2Ptr == &tclWideIntType) {
	    TclGetWide(w2,value2Ptr);
	} else if ((t2Ptr == &tclDoubleType)
		   && (value2Ptr->bytes == NULL)) {
	    /*
	     * We can only use the internal rep directly if there is
	     * no string rep.  Otherwise the string rep might actually
	     * look like an integer, which is preferred.
	     */

	    d2 = value2Ptr->internalRep.doubleValue;
	} else {
	    char *s = Tcl_GetStringFromObj(value2Ptr, &length);
	    if (TclLooksLikeInt(s, length)) {
		GET_WIDE_OR_INT(result, value2Ptr, i2, w2);
	    } else {
		result = Tcl_GetDoubleFromObj((Tcl_Interp *) NULL,
		        value2Ptr, &d2);
	    }
	    if (result != TCL_OK) {
		TRACE(("%.20s %.20s => ILLEGAL 2nd TYPE %s\n",
		        O2S(value2Ptr), s,
		        (value2Ptr->typePtr?
			    value2Ptr->typePtr->name : "null")));
		DECACHE_STACK_INFO();
		IllegalExprOperandType(interp, pc, value2Ptr);
		CACHE_STACK_INFO();
		goto checkForCatch;
	    }
	    t2Ptr = value2Ptr->typePtr;
	}

	if ((t1Ptr == &tclDoubleType) || (t2Ptr == &tclDoubleType)) {
	    /*
	     * Do double arithmetic.
	     */
	    doDouble = 1;
	    if (t1Ptr == &tclIntType) {
		d1 = i;       /* promote value 1 to double */
	    } else if (t2Ptr == &tclIntType) {
		d2 = i2;      /* promote value 2 to double */
	    } else if (t1Ptr == &tclWideIntType) {
		d1 = Tcl_WideAsDouble(w);
	    } else if (t2Ptr == &tclWideIntType) {
		d2 = Tcl_WideAsDouble(w2);
	    }
	    switch (*pc) {
	        case INST_ADD:
		    dResult = d1 + d2;
		    break;
	        case INST_SUB:
		    dResult = d1 - d2;
		    break;
	        case INST_MULT:
		    dResult = d1 * d2;
		    break;
	        case INST_DIV:
		    if (d2 == 0.0) {
			TRACE(("%.6g %.6g => DIVIDE BY ZERO\n", d1, d2));
			goto divideByZero;
		    }
		    dResult = d1 / d2;
		    break;
	    }
		    
	    /*
	     * Check now for IEEE floating-point error.
	     */
		    
	    if (IS_NAN(dResult) || IS_INF(dResult)) {
		TRACE(("%.20s %.20s => IEEE FLOATING PT ERROR\n",
		        O2S(valuePtr), O2S(value2Ptr)));
		DECACHE_STACK_INFO();
		TclExprFloatError(interp, dResult);
		CACHE_STACK_INFO();
		result = TCL_ERROR;
		goto checkForCatch;
	    }
	} else if ((t1Ptr == &tclWideIntType) 
		   || (t2Ptr == &tclWideIntType)) {
	    /*
	     * Do wide integer arithmetic.
	     */
	    doWide = 1;
	    if (t1Ptr == &tclIntType) {
		w = Tcl_LongAsWide(i);
	    } else if (t2Ptr == &tclIntType) {
		w2 = Tcl_LongAsWide(i2);
	    }
	    switch (*pc) {
	        case INST_ADD:
		    wResult = w + w2;
		    break;
	        case INST_SUB:
		    wResult = w - w2;
		    break;
	        case INST_MULT:
		    wResult = w * w2;
		    break;
	        case INST_DIV:
		    /*
		     * This code is tricky: C doesn't guarantee much
		     * about the quotient or remainder, but Tcl does.
		     * The remainder always has the same sign as the
		     * divisor and a smaller absolute value.
		     */
		    if (w2 == W0) {
			TRACE((LLD" "LLD" => DIVIDE BY ZERO\n", w, w2));
			goto divideByZero;
		    }
		    if (w2 < 0) {
			w2 = -w2;
			w = -w;
		    }
		    wquot = w / w2;
		    wrem  = w % w2;
		    if (wrem < W0) {
			wquot -= 1;
		    }
		    wResult = wquot;
		    break;
	    }
	} else {
	    /*
		     * Do integer arithmetic.
		     */
	    switch (*pc) {
	        case INST_ADD:
		    iResult = i + i2;
		    break;
	        case INST_SUB:
		    iResult = i - i2;
		    break;
	        case INST_MULT:
		    iResult = i * i2;
		    break;
	        case INST_DIV:
		    /*
		     * This code is tricky: C doesn't guarantee much
		     * about the quotient or remainder, but Tcl does.
		     * The remainder always has the same sign as the
		     * divisor and a smaller absolute value.
		     */
		    if (i2 == 0) {
			TRACE(("%ld %ld => DIVIDE BY ZERO\n", i, i2));
			goto divideByZero;
		    }
		    if (i2 < 0) {
			i2 = -i2;
			i = -i;
		    }
		    quot = i / i2;
		    rem  = i % i2;
		    if (rem < 0) {
			quot -= 1;
		    }
		    iResult = quot;
		    break;
	    }
	}

	/*
	 * Reuse the valuePtr object already on stack if possible.
	 */
		
	if (Tcl_IsShared(valuePtr)) {
	    if (doDouble) {
		objResultPtr = Tcl_NewDoubleObj(dResult);
		TRACE(("%.6g %.6g => %.6g\n", d1, d2, dResult));
	    } else if (doWide) {
		objResultPtr = Tcl_NewWideIntObj(wResult);
		TRACE((LLD" "LLD" => "LLD"\n", w, w2, wResult));
	    } else {
		objResultPtr = Tcl_NewLongObj(iResult);
		TRACE(("%ld %ld => %ld\n", i, i2, iResult));
	    } 
	    NEXT_INST_F(1, 2, 1);
	} else {	    /* reuse the valuePtr object */
	    if (doDouble) { /* NB: stack top is off by 1 */
		TRACE(("%.6g %.6g => %.6g\n", d1, d2, dResult));
		Tcl_SetDoubleObj(valuePtr, dResult);
	    } else if (doWide) {
		TRACE((LLD" "LLD" => "LLD"\n", w, w2, wResult));
		Tcl_SetWideIntObj(valuePtr, wResult);
	    } else {
		TRACE(("%ld %ld => %ld\n", i, i2, iResult));
		Tcl_SetLongObj(valuePtr, iResult);
	    }
	    NEXT_INST_F(1, 1, 0);
	}
    }

    case INST_UPLUS:
    {
	/*
	 * Operand must be numeric.
	 */

	double d;
	Tcl_ObjType *tPtr;
		
	valuePtr = stackPtr[stackTop];
	tPtr = valuePtr->typePtr;
	if (!IS_INTEGER_TYPE(tPtr) && ((tPtr != &tclDoubleType) 
                || (valuePtr->bytes != NULL))) {
	    char *s = Tcl_GetStringFromObj(valuePtr, &length);
	    if (TclLooksLikeInt(s, length)) {
		GET_WIDE_OR_INT(result, valuePtr, i, w);
	    } else {
		result = Tcl_GetDoubleFromObj((Tcl_Interp *) NULL, valuePtr, &d);
	    }
	    if (result != TCL_OK) { 
		TRACE(("\"%.20s\" => ILLEGAL TYPE %s \n",
		        s, (tPtr? tPtr->name : "null")));
		DECACHE_STACK_INFO();
		IllegalExprOperandType(interp, pc, valuePtr);
		CACHE_STACK_INFO();
		goto checkForCatch;
	    }
	    tPtr = valuePtr->typePtr;
	}

	/*
	 * Ensure that the operand's string rep is the same as the
	 * formatted version of its internal rep. This makes sure
	 * that "expr +000123" yields "83", not "000123". We
	 * implement this by _discarding_ the string rep since we
	 * know it will be regenerated, if needed later, by
	 * formatting the internal rep's value.
	 */

	if (Tcl_IsShared(valuePtr)) {
	    if (tPtr == &tclIntType) {
		i = valuePtr->internalRep.longValue;
		objResultPtr = Tcl_NewLongObj(i);
	    } else if (tPtr == &tclWideIntType) {
		TclGetWide(w,valuePtr);
		objResultPtr = Tcl_NewWideIntObj(w);
	    } else {
		d = valuePtr->internalRep.doubleValue;
		objResultPtr = Tcl_NewDoubleObj(d);
	    }
	    TRACE_WITH_OBJ(("%s => ", O2S(objResultPtr)), objResultPtr);
	    NEXT_INST_F(1, 1, 1);
	} else {
	    Tcl_InvalidateStringRep(valuePtr);
	    TRACE_WITH_OBJ(("%s => ", O2S(valuePtr)), valuePtr);
	    NEXT_INST_F(1, 0, 0);
	}
    }
	    
    case INST_UMINUS:
    case INST_LNOT:
    {
	/*
	 * The operand must be numeric or a boolean string as
	 * accepted by Tcl_GetBooleanFromObj(). If the operand
	 * object is unshared modify it directly, otherwise
	 * create a copy to modify: this is "copy on write".
	 * Free any old string representation since it is now
	 * invalid.
	 */

	double d;
	int boolvar;
	Tcl_ObjType *tPtr;

	valuePtr = stackPtr[stackTop];
	tPtr = valuePtr->typePtr;
	if (!IS_INTEGER_TYPE(tPtr) && ((tPtr != &tclDoubleType)
	        || (valuePtr->bytes != NULL))) {
	    if ((tPtr == &tclBooleanType) && (valuePtr->bytes == NULL)) {
		valuePtr->typePtr = &tclIntType;
	    } else {
		char *s = Tcl_GetStringFromObj(valuePtr, &length);
		if (TclLooksLikeInt(s, length)) {
		    GET_WIDE_OR_INT(result, valuePtr, i, w);
		} else {
		    result = Tcl_GetDoubleFromObj((Tcl_Interp *) NULL,
		            valuePtr, &d);
		}
		if (result == TCL_ERROR && *pc == INST_LNOT) {
		    result = Tcl_GetBooleanFromObj((Tcl_Interp *)NULL,
		            valuePtr, &boolvar);
		    i = (long)boolvar; /* i is long, not int! */
		}
		if (result != TCL_OK) {
		    TRACE(("\"%.20s\" => ILLEGAL TYPE %s\n",
		            s, (tPtr? tPtr->name : "null")));
		    DECACHE_STACK_INFO();
		    IllegalExprOperandType(interp, pc, valuePtr);
		    CACHE_STACK_INFO();
		    goto checkForCatch;
		}
	    }
	    tPtr = valuePtr->typePtr;
	}

	if (Tcl_IsShared(valuePtr)) {
	    /*
	     * Create a new object.
	     */
	    if ((tPtr == &tclIntType) || (tPtr == &tclBooleanType)) {
		i = valuePtr->internalRep.longValue;
		objResultPtr = Tcl_NewLongObj(
		    (*pc == INST_UMINUS)? -i : !i);
		TRACE_WITH_OBJ(("%ld => ", i), objResultPtr);
	    } else if (tPtr == &tclWideIntType) {
		TclGetWide(w,valuePtr);
		if (*pc == INST_UMINUS) {
		    objResultPtr = Tcl_NewWideIntObj(-w);
		} else {
		    objResultPtr = Tcl_NewLongObj(w == W0);
		}
		TRACE_WITH_OBJ((LLD" => ", w), objResultPtr);
	    } else {
		d = valuePtr->internalRep.doubleValue;
		if (*pc == INST_UMINUS) {
		    objResultPtr = Tcl_NewDoubleObj(-d);
		} else {
		    /*
		     * Should be able to use "!d", but apparently
		     * some compilers can't handle it.
		     */
		    objResultPtr = Tcl_NewLongObj((d==0.0)? 1 : 0);
		}
		TRACE_WITH_OBJ(("%.6g => ", d), objResultPtr);
	    }
	    NEXT_INST_F(1, 1, 1);
	} else {
	    /*
	     * valuePtr is unshared. Modify it directly.
	     */
	    if ((tPtr == &tclIntType) || (tPtr == &tclBooleanType)) {
		i = valuePtr->internalRep.longValue;
		Tcl_SetLongObj(valuePtr,
	                (*pc == INST_UMINUS)? -i : !i);
		TRACE_WITH_OBJ(("%ld => ", i), valuePtr);
	    } else if (tPtr == &tclWideIntType) {
		TclGetWide(w,valuePtr);
		if (*pc == INST_UMINUS) {
		    Tcl_SetWideIntObj(valuePtr, -w);
		} else {
		    Tcl_SetLongObj(valuePtr, w == W0);
		}
		TRACE_WITH_OBJ((LLD" => ", w), valuePtr);
	    } else {
		d = valuePtr->internalRep.doubleValue;
		if (*pc == INST_UMINUS) {
		    Tcl_SetDoubleObj(valuePtr, -d);
		} else {
		    /*
		     * Should be able to use "!d", but apparently
		     * some compilers can't handle it.
		     */
		    Tcl_SetLongObj(valuePtr, (d==0.0)? 1 : 0);
		}
		TRACE_WITH_OBJ(("%.6g => ", d), valuePtr);
	    }
	    NEXT_INST_F(1, 0, 0);
	}
    }

    case INST_BITNOT:
    {
	/*
	 * The operand must be an integer. If the operand object is
	 * unshared modify it directly, otherwise modify a copy. 
	 * Free any old string representation since it is now
	 * invalid.
	 */
		
	Tcl_ObjType *tPtr;
		
	valuePtr = stackPtr[stackTop];
	tPtr = valuePtr->typePtr;
	if (!IS_INTEGER_TYPE(tPtr)) {
	    REQUIRE_WIDE_OR_INT(result, valuePtr, i, w);
	    if (result != TCL_OK) {   /* try to convert to double */
		TRACE(("\"%.20s\" => ILLEGAL TYPE %s\n",
		        O2S(valuePtr), (tPtr? tPtr->name : "null")));
		DECACHE_STACK_INFO();
		IllegalExprOperandType(interp, pc, valuePtr);
		CACHE_STACK_INFO();
		goto checkForCatch;
	    }
	}
		
	if (valuePtr->typePtr == &tclWideIntType) {
	    TclGetWide(w,valuePtr);
	    if (Tcl_IsShared(valuePtr)) {
		objResultPtr = Tcl_NewWideIntObj(~w);
		TRACE(("0x%llx => (%llu)\n", w, ~w));
		NEXT_INST_F(1, 1, 1);
	    } else {
		/*
		 * valuePtr is unshared. Modify it directly.
		 */
		Tcl_SetWideIntObj(valuePtr, ~w);
		TRACE(("0x%llx => (%llu)\n", w, ~w));
		NEXT_INST_F(1, 0, 0);
	    }
	} else {
	    i = valuePtr->internalRep.longValue;
	    if (Tcl_IsShared(valuePtr)) {
		objResultPtr = Tcl_NewLongObj(~i);
		TRACE(("0x%lx => (%lu)\n", i, ~i));
		NEXT_INST_F(1, 1, 1);
	    } else {
		/*
		 * valuePtr is unshared. Modify it directly.
		 */
		Tcl_SetLongObj(valuePtr, ~i);
		TRACE(("0x%lx => (%lu)\n", i, ~i));
		NEXT_INST_F(1, 0, 0);
	    }
	}
    }

    case INST_CALL_BUILTIN_FUNC1:
	opnd = TclGetUInt1AtPtr(pc+1);
	{
	    /*
	     * Call one of the built-in Tcl math functions.
	     */

	    BuiltinFunc *mathFuncPtr;

	    if ((opnd < 0) || (opnd > LAST_BUILTIN_FUNC)) {
		TRACE(("UNRECOGNIZED BUILTIN FUNC CODE %d\n", opnd));
		panic("TclExecuteByteCode: unrecognized builtin function code %d", opnd);
	    }
	    mathFuncPtr = &(tclBuiltinFuncTable[opnd]);
	    DECACHE_STACK_INFO();
	    result = (*mathFuncPtr->proc)(interp, eePtr,
	            mathFuncPtr->clientData);
	    CACHE_STACK_INFO();
	    if (result != TCL_OK) {
		goto checkForCatch;
	    }
	    TRACE_WITH_OBJ(("%d => ", opnd), stackPtr[stackTop]);
	}
	NEXT_INST_F(2, 0, 0);
		    
    case INST_CALL_FUNC1:
	opnd = TclGetUInt1AtPtr(pc+1);
	{
	    /*
	     * Call a non-builtin Tcl math function previously
	     * registered by a call to Tcl_CreateMathFunc.
	     */
		
	    int objc = opnd;   /* Number of arguments. The function name
				* is the 0-th argument. */
	    Tcl_Obj **objv;    /* The array of arguments. The function
				* name is objv[0]. */

	    objv = &(stackPtr[stackTop - (objc-1)]); /* "objv[0]" */
	    DECACHE_STACK_INFO();
	    result = ExprCallMathFunc(interp, eePtr, objc, objv);
	    CACHE_STACK_INFO();
	    if (result != TCL_OK) {
		goto checkForCatch;
	    }
	    TRACE_WITH_OBJ(("%d => ", objc), stackPtr[stackTop]);
	}
	NEXT_INST_F(2, 0, 0);

    case INST_TRY_CVT_TO_NUMERIC:
    {
	/*
	 * Try to convert the topmost stack object to an int or
	 * double object. This is done in order to support Tcl's
	 * policy of interpreting operands if at all possible as
	 * first integers, else floating-point numbers.
	 */
		
	double d;
	char *s;
	Tcl_ObjType *tPtr;
	int converted, needNew;

	valuePtr = stackPtr[stackTop];
	tPtr = valuePtr->typePtr;
	converted = 0;
	if (!IS_INTEGER_TYPE(tPtr) && ((tPtr != &tclDoubleType)
	        || (valuePtr->bytes != NULL))) {
	    if ((tPtr == &tclBooleanType) && (valuePtr->bytes == NULL)) {
		valuePtr->typePtr = &tclIntType;
		converted = 1;
	    } else {
		s = Tcl_GetStringFromObj(valuePtr, &length);
		if (TclLooksLikeInt(s, length)) {
		    GET_WIDE_OR_INT(result, valuePtr, i, w);
		} else {
		    result = Tcl_GetDoubleFromObj((Tcl_Interp *) NULL,
		            valuePtr, &d);
		}
		if (result == TCL_OK) {
		    converted = 1;
		}
		result = TCL_OK; /* reset the result variable */
	    }
	    tPtr = valuePtr->typePtr;
	}

	/*
	 * Ensure that the topmost stack object, if numeric, has a
	 * string rep the same as the formatted version of its
	 * internal rep. This is used, e.g., to make sure that "expr
	 * {0001}" yields "1", not "0001". We implement this by
	 * _discarding_ the string rep since we know it will be
	 * regenerated, if needed later, by formatting the internal
	 * rep's value. Also check if there has been an IEEE
	 * floating point error.
	 */
	
	objResultPtr = valuePtr;
	needNew = 0;
	if (IS_NUMERIC_TYPE(tPtr)) {
	    if (Tcl_IsShared(valuePtr)) {
		if (valuePtr->bytes != NULL) {
		    /*
		     * We only need to make a copy of the object
		     * when it already had a string rep
		     */
		    needNew = 1;
		    if (tPtr == &tclIntType) {
			i = valuePtr->internalRep.longValue;
			objResultPtr = Tcl_NewLongObj(i);
		    } else if (tPtr == &tclWideIntType) {
			TclGetWide(w,valuePtr);
			objResultPtr = Tcl_NewWideIntObj(w);
		    } else {
			d = valuePtr->internalRep.doubleValue;
			objResultPtr = Tcl_NewDoubleObj(d);
		    }
		    tPtr = objResultPtr->typePtr;
		}
	    } else {
		Tcl_InvalidateStringRep(valuePtr);
	    }
		
	    if (tPtr == &tclDoubleType) {
		d = objResultPtr->internalRep.doubleValue;
		if (IS_NAN(d) || IS_INF(d)) {
		    TRACE(("\"%.20s\" => IEEE FLOATING PT ERROR\n",
		            O2S(objResultPtr)));
		    DECACHE_STACK_INFO();
		    TclExprFloatError(interp, d);
		    CACHE_STACK_INFO();
		    result = TCL_ERROR;
		    goto checkForCatch;
		}
	    }
	    converted = converted;  /* lint, converted not used. */
	    TRACE(("\"%.20s\" => numeric, %s, %s\n", O2S(valuePtr),
	            (converted? "converted" : "not converted"),
		    (needNew? "new Tcl_Obj" : "same Tcl_Obj")));
	} else {
	    TRACE(("\"%.20s\" => not numeric\n", O2S(valuePtr)));
	}
	if (needNew) {
	    NEXT_INST_F(1, 1, 1);
	} else {
	    NEXT_INST_F(1, 0, 0);
	}
    }
	
    case INST_BREAK:
	DECACHE_STACK_INFO();
	Tcl_ResetResult(interp);
	CACHE_STACK_INFO();
	result = TCL_BREAK;
	cleanup = 0;
	goto processExceptionReturn;

    case INST_CONTINUE:
	DECACHE_STACK_INFO();
	Tcl_ResetResult(interp);
	CACHE_STACK_INFO();
	result = TCL_CONTINUE;
	cleanup = 0;
	goto processExceptionReturn;

    case INST_FOREACH_START4:
	opnd = TclGetUInt4AtPtr(pc+1);
	{
	    /*
	     * Initialize the temporary local var that holds the count
	     * of the number of iterations of the loop body to -1.
	     */

	    ForeachInfo *infoPtr = (ForeachInfo *)
	            codePtr->auxDataArrayPtr[opnd].clientData;
	    int iterTmpIndex = infoPtr->loopCtTemp;
	    Var *compiledLocals = iPtr->varFramePtr->compiledLocals;
	    Var *iterVarPtr = &(compiledLocals[iterTmpIndex]);
	    Tcl_Obj *oldValuePtr = iterVarPtr->value.objPtr;

	    if (oldValuePtr == NULL) {
		iterVarPtr->value.objPtr = Tcl_NewLongObj(-1);
		Tcl_IncrRefCount(iterVarPtr->value.objPtr);
	    } else {
		Tcl_SetLongObj(oldValuePtr, -1);
	    }
	    TclSetVarScalar(iterVarPtr);
	    TclClearVarUndefined(iterVarPtr);
	    TRACE(("%u => loop iter count temp %d\n", 
		   opnd, iterTmpIndex));
	}
	    
#ifndef TCL_COMPILE_DEBUG
	/* 
	 * Remark that the compiler ALWAYS sets INST_FOREACH_STEP4
	 * immediately after INST_FOREACH_START4 - let us just fall
	 * through instead of jumping back to the top.
	 */

	pc += 5;
#else
	NEXT_INST_F(5, 0, 0);
#endif	
    case INST_FOREACH_STEP4:
	opnd = TclGetUInt4AtPtr(pc+1);
	{
	    /*
	     * "Step" a foreach loop (i.e., begin its next iteration) by
	     * assigning the next value list element to each loop var.
	     */

	    ForeachInfo *infoPtr = (ForeachInfo *)
	            codePtr->auxDataArrayPtr[opnd].clientData;
	    ForeachVarList *varListPtr;
	    int numLists = infoPtr->numLists;
	    Var *compiledLocals = iPtr->varFramePtr->compiledLocals;
	    Tcl_Obj *listPtr;
	    List *listRepPtr;
	    Var *iterVarPtr, *listVarPtr;
	    int iterNum, listTmpIndex, listLen, numVars;
	    int varIndex, valIndex, continueLoop, j;

	    /*
	     * Increment the temp holding the loop iteration number.
	     */

	    iterVarPtr = &(compiledLocals[infoPtr->loopCtTemp]);
	    valuePtr = iterVarPtr->value.objPtr;
	    iterNum = (valuePtr->internalRep.longValue + 1);
	    Tcl_SetLongObj(valuePtr, iterNum);
		
	    /*
	     * Check whether all value lists are exhausted and we should
	     * stop the loop.
	     */

	    continueLoop = 0;
	    listTmpIndex = infoPtr->firstValueTemp;
	    for (i = 0;  i < numLists;  i++) {
		varListPtr = infoPtr->varLists[i];
		numVars = varListPtr->numVars;
		    
		listVarPtr = &(compiledLocals[listTmpIndex]);
		listPtr = listVarPtr->value.objPtr;
		result = Tcl_ListObjLength(interp, listPtr, &listLen);
		if (result != TCL_OK) {
		    TRACE_WITH_OBJ(("%u => ERROR converting list %ld, \"%s\": ",
		            opnd, i, O2S(listPtr)), Tcl_GetObjResult(interp));
		    goto checkForCatch;
		}
		if (listLen > (iterNum * numVars)) {
		    continueLoop = 1;
		}
		listTmpIndex++;
	    }

	    /*
	     * If some var in some var list still has a remaining list
	     * element iterate one more time. Assign to var the next
	     * element from its value list. We already checked above
	     * that each list temp holds a valid list object.
	     */
		
	    if (continueLoop) {
		listTmpIndex = infoPtr->firstValueTemp;
		for (i = 0;  i < numLists;  i++) {
		    varListPtr = infoPtr->varLists[i];
		    numVars = varListPtr->numVars;

		    listVarPtr = &(compiledLocals[listTmpIndex]);
		    listPtr = listVarPtr->value.objPtr;
		    listRepPtr = (List *) listPtr->internalRep.twoPtrValue.ptr1;
		    listLen = listRepPtr->elemCount;
			
		    valIndex = (iterNum * numVars);
		    for (j = 0;  j < numVars;  j++) {
			int setEmptyStr = 0;
			if (valIndex >= listLen) {
			    setEmptyStr = 1;
			    TclNewObj(valuePtr);
			} else {
			    valuePtr = listRepPtr->elements[valIndex];
			}
			    
			varIndex = varListPtr->varIndexes[j];
			varPtr = &(varFramePtr->compiledLocals[varIndex]);
			part1 = varPtr->name;
			while (TclIsVarLink(varPtr)) {
			    varPtr = varPtr->value.linkPtr;
			}
			if (!((varPtr->flags & VAR_IN_HASHTABLE) && (varPtr->hPtr == NULL))
			        && (varPtr->tracePtr == NULL)
			        && (TclIsVarScalar(varPtr) || TclIsVarUndefined(varPtr))) {
			    value2Ptr = varPtr->value.objPtr;
			    if (valuePtr != value2Ptr) {
				if (value2Ptr != NULL) {
				    TclDecrRefCount(value2Ptr);
				} else {
				    TclSetVarScalar(varPtr);
				    TclClearVarUndefined(varPtr);
				}
				varPtr->value.objPtr = valuePtr;
				Tcl_IncrRefCount(valuePtr);
			    }
			} else {
			    DECACHE_STACK_INFO();
			    value2Ptr = TclPtrSetVar(interp, varPtr, NULL, part1, 
						     NULL, valuePtr, TCL_LEAVE_ERR_MSG);
			    CACHE_STACK_INFO();
			    if (value2Ptr == NULL) {
				TRACE_WITH_OBJ(("%u => ERROR init. index temp %d: ",
						opnd, varIndex),
					       Tcl_GetObjResult(interp));
				if (setEmptyStr) {
				    TclDecrRefCount(valuePtr);
				}
				result = TCL_ERROR;
				goto checkForCatch;
			    }
			}
			valIndex++;
		    }
		    listTmpIndex++;
		}
	    }
	    TRACE(("%u => %d lists, iter %d, %s loop\n", opnd, numLists, 
	            iterNum, (continueLoop? "continue" : "exit")));

	    /* 
	     * Run-time peep-hole optimisation: the compiler ALWAYS follows
	     * INST_FOREACH_STEP4 with an INST_JUMP_FALSE. We just skip that
	     * instruction and jump direct from here.
	     */

	    pc += 5;
	    if (*pc == INST_JUMP_FALSE1) {
		NEXT_INST_F((continueLoop? 2 : TclGetInt1AtPtr(pc+1)), 0, 0);
	    } else {
		NEXT_INST_F((continueLoop? 5 : TclGetInt4AtPtr(pc+1)), 0, 0);
	    }
	}

    case INST_BEGIN_CATCH4:
	/*
	 * Record start of the catch command with exception range index
	 * equal to the operand. Push the current stack depth onto the
	 * special catch stack.
	 */
	catchStackPtr[++catchTop] = stackTop;
	TRACE(("%u => catchTop=%d, stackTop=%d\n",
	       TclGetUInt4AtPtr(pc+1), catchTop, stackTop));
	NEXT_INST_F(5, 0, 0);

    case INST_END_CATCH:
	catchTop--;
	result = TCL_OK;
	TRACE(("=> catchTop=%d\n", catchTop));
	NEXT_INST_F(1, 0, 0);
	    
    case INST_PUSH_RESULT:
	objResultPtr = Tcl_GetObjResult(interp);
	TRACE_WITH_OBJ(("=> "), Tcl_GetObjResult(interp));

	/*
	 * See the comments at INST_INVOKE_STK
	 */
	{
	    Tcl_Obj *newObjResultPtr;
	    TclNewObj(newObjResultPtr);
	    Tcl_IncrRefCount(newObjResultPtr);
	    iPtr->objResultPtr = newObjResultPtr;
	}

	NEXT_INST_F(1, 0, -1);

    case INST_PUSH_RETURN_CODE:
	objResultPtr = Tcl_NewLongObj(result);
	TRACE(("=> %u\n", result));
	NEXT_INST_F(1, 0, 1);

    default:
	panic("TclExecuteByteCode: unrecognized opCode %u", *pc);
    } /* end of switch on opCode */

    /*
     * Division by zero in an expression. Control only reaches this
     * point by "goto divideByZero".
     */
	
 divideByZero:
    DECACHE_STACK_INFO();
    Tcl_ResetResult(interp);
    Tcl_AppendToObj(Tcl_GetObjResult(interp), "divide by zero", -1);
    Tcl_SetErrorCode(interp, "ARITH", "DIVZERO", "divide by zero",
            (char *) NULL);
    CACHE_STACK_INFO();

    result = TCL_ERROR;
    goto checkForCatch;
	
    /*
     * An external evaluation (INST_INVOKE or INST_EVAL) returned 
     * something different from TCL_OK, or else INST_BREAK or 
     * INST_CONTINUE were called.
     */

 processExceptionReturn:
#if TCL_COMPILE_DEBUG    
    switch (*pc) {
        case INST_INVOKE_STK1:
        case INST_INVOKE_STK4:
	    TRACE(("%u => ... after \"%.20s\": ", opnd, cmdNameBuf));
	    break;
        case INST_EVAL_STK:
	    /*
	     * Note that the object at stacktop has to be used
	     * before doing the cleanup.
	     */

	    TRACE(("\"%.30s\" => ", O2S(stackPtr[stackTop])));
	    break;
        default:
	    TRACE(("=> "));
    }		    
#endif	   
    if ((result == TCL_CONTINUE) || (result == TCL_BREAK)) {
	rangePtr = GetExceptRangeForPc(pc, /*catchOnly*/ 0, codePtr);
	if (rangePtr == NULL) {
	    TRACE_APPEND(("no encl. loop or catch, returning %s\n",
	            StringForResultCode(result)));
	    goto abnormalReturn;
	} 
	if (rangePtr->type == CATCH_EXCEPTION_RANGE) {
	    TRACE_APPEND(("%s ...\n", StringForResultCode(result)));
	    goto processCatch;
	}
	while (cleanup--) {
	    valuePtr = POP_OBJECT();
	    TclDecrRefCount(valuePtr);
	}
	if (result == TCL_BREAK) {
	    result = TCL_OK;
	    pc = (codePtr->codeStart + rangePtr->breakOffset);
	    TRACE_APPEND(("%s, range at %d, new pc %d\n",
		   StringForResultCode(result),
		   rangePtr->codeOffset, rangePtr->breakOffset));
	    NEXT_INST_F(0, 0, 0);
	} else {
	    if (rangePtr->continueOffset == -1) {
		TRACE_APPEND(("%s, loop w/o continue, checking for catch\n",
		        StringForResultCode(result)));
		goto checkForCatch;
	    } 
	    result = TCL_OK;
	    pc = (codePtr->codeStart + rangePtr->continueOffset);
	    TRACE_APPEND(("%s, range at %d, new pc %d\n",
		   StringForResultCode(result),
		   rangePtr->codeOffset, rangePtr->continueOffset));
	    NEXT_INST_F(0, 0, 0);
	}
#if TCL_COMPILE_DEBUG    
    } else if (traceInstructions) {
	if ((result != TCL_ERROR) && (result != TCL_RETURN))  {
	    objPtr = Tcl_GetObjResult(interp);
	    TRACE_APPEND(("OTHER RETURN CODE %d, result= \"%s\"\n ", 
		    result, O2S(objPtr)));
	} else {
	    objPtr = Tcl_GetObjResult(interp);
	    TRACE_APPEND(("%s, result= \"%s\"\n", 
	            StringForResultCode(result), O2S(objPtr)));
	}
#endif
    }
	    	
    /*
     * Execution has generated an "exception" such as TCL_ERROR. If the
     * exception is an error, record information about what was being
     * executed when the error occurred. Find the closest enclosing
     * catch range, if any. If no enclosing catch range is found, stop
     * execution and return the "exception" code.
     */
	
 checkForCatch:
    if ((result == TCL_ERROR) && !(iPtr->flags & ERR_ALREADY_LOGGED)) {
	bytes = GetSrcInfoForPc(pc, codePtr, &length);
	if (bytes != NULL) {
	    DECACHE_STACK_INFO();
	    Tcl_LogCommandInfo(interp, codePtr->source, bytes, length);
            CACHE_STACK_INFO();
	    iPtr->flags |= ERR_ALREADY_LOGGED;
	}
    }
    if (catchTop == -1) {
#ifdef TCL_COMPILE_DEBUG
	if (traceInstructions) {
	    fprintf(stdout, "   ... no enclosing catch, returning %s\n",
	            StringForResultCode(result));
	}
#endif
	goto abnormalReturn;
    }
    rangePtr = GetExceptRangeForPc(pc, /*catchOnly*/ 1, codePtr);
    if (rangePtr == NULL) {
	/*
	 * This is only possible when compiling a [catch] that sends its
	 * script to INST_EVAL. Cannot correct the compiler without 
	 * breakingcompat with previous .tbc compiled scripts.
	 */
#ifdef TCL_COMPILE_DEBUG
	if (traceInstructions) {
	    fprintf(stdout, "   ... no enclosing catch, returning %s\n",
	            StringForResultCode(result));
	}
#endif
	goto abnormalReturn;
    }

    /*
     * A catch exception range (rangePtr) was found to handle an
     * "exception". It was found either by checkForCatch just above or
     * by an instruction during break, continue, or error processing.
     * Jump to its catchOffset after unwinding the operand stack to
     * the depth it had when starting to execute the range's catch
     * command.
     */

 processCatch:
    while (stackTop > catchStackPtr[catchTop]) {
	valuePtr = POP_OBJECT();
	TclDecrRefCount(valuePtr);
    }
#ifdef TCL_COMPILE_DEBUG
    if (traceInstructions) {
	fprintf(stdout, "  ... found catch at %d, catchTop=%d, unwound to %d, new pc %u\n",
	        rangePtr->codeOffset, catchTop, catchStackPtr[catchTop],
	        (unsigned int)(rangePtr->catchOffset));
    }
#endif	
    pc = (codePtr->codeStart + rangePtr->catchOffset);
    NEXT_INST_F(0, 0, 0); /* restart the execution loop at pc */

    /* 
     * end of infinite loop dispatching on instructions.
     */

    /*
     * Abnormal return code. Restore the stack to state it had when starting
     * to execute the ByteCode. Panic if the stack is below the initial level.
     */

 abnormalReturn:
    while (stackTop > initStackTop) {
	valuePtr = POP_OBJECT();
	TclDecrRefCount(valuePtr);
    }
    if (stackTop < initStackTop) {
	fprintf(stderr, "\nTclExecuteByteCode: abnormal return at pc %u: stack top %d < entry stack top %d\n",
	        (unsigned int)(pc - codePtr->codeStart),
		(unsigned int) stackTop,
		(unsigned int) initStackTop);
	panic("TclExecuteByteCode execution failure: end stack top < start stack top");
    }
	
    /*
     * Free the catch stack array if malloc'ed storage was used.
     */

    if (catchStackPtr != catchStackStorage) {
	ckfree((char *) catchStackPtr);
    }
    eePtr->stackTop = initStackTop;
    return result;
#undef STATIC_CATCH_STACK_SIZE
}

#ifdef TCL_COMPILE_DEBUG
/*
 *----------------------------------------------------------------------
 *
 * PrintByteCodeInfo --
 *
 *	This procedure prints a summary about a bytecode object to stdout.
 *	It is called by TclExecuteByteCode when starting to execute the
 *	bytecode object if tclTraceExec has the value 2 or more.
 *
 * Results:
 *	None.
 *
 * Side effects:
 *	None.
 *
 *----------------------------------------------------------------------
 */

static void
PrintByteCodeInfo(codePtr)
    register ByteCode *codePtr;	/* The bytecode whose summary is printed
				 * to stdout. */
{
    Proc *procPtr = codePtr->procPtr;
    Interp *iPtr = (Interp *) *codePtr->interpHandle;

    fprintf(stdout, "\nExecuting ByteCode 0x%x, refCt %u, epoch %u, interp 0x%x (epoch %u)\n",
	    (unsigned int) codePtr, codePtr->refCount,
	    codePtr->compileEpoch, (unsigned int) iPtr,
	    iPtr->compileEpoch);
    
    fprintf(stdout, "  Source: ");
    TclPrintSource(stdout, codePtr->source, 60);

    fprintf(stdout, "\n  Cmds %d, src %d, inst %u, litObjs %u, aux %d, stkDepth %u, code/src %.2f\n",
            codePtr->numCommands, codePtr->numSrcBytes,
	    codePtr->numCodeBytes, codePtr->numLitObjects,
	    codePtr->numAuxDataItems, codePtr->maxStackDepth,
#ifdef TCL_COMPILE_STATS
	    (codePtr->numSrcBytes?
	            ((float)codePtr->structureSize)/((float)codePtr->numSrcBytes) : 0.0));
#else
	    0.0);
#endif
#ifdef TCL_COMPILE_STATS
    fprintf(stdout, "  Code %d = header %d+inst %d+litObj %d+exc %d+aux %d+cmdMap %d\n",
	    codePtr->structureSize,
	    (sizeof(ByteCode) - (sizeof(size_t) + sizeof(Tcl_Time))),
	    codePtr->numCodeBytes,
	    (codePtr->numLitObjects * sizeof(Tcl_Obj *)),
	    (codePtr->numExceptRanges * sizeof(ExceptionRange)),
	    (codePtr->numAuxDataItems * sizeof(AuxData)),
	    codePtr->numCmdLocBytes);
#endif /* TCL_COMPILE_STATS */
    if (procPtr != NULL) {
	fprintf(stdout,
		"  Proc 0x%x, refCt %d, args %d, compiled locals %d\n",
		(unsigned int) procPtr, procPtr->refCount,
		procPtr->numArgs, procPtr->numCompiledLocals);
    }
}
#endif /* TCL_COMPILE_DEBUG */

/*
 *----------------------------------------------------------------------
 *
 * ValidatePcAndStackTop --
 *
 *	This procedure is called by TclExecuteByteCode when debugging to
 *	verify that the program counter and stack top are valid during
 *	execution.
 *
 * Results:
 *	None.
 *
 * Side effects:
 *	Prints a message to stderr and panics if either the pc or stack
 *	top are invalid.
 *
 *----------------------------------------------------------------------
 */

#ifdef TCL_COMPILE_DEBUG
static void
ValidatePcAndStackTop(codePtr, pc, stackTop, stackLowerBound)
    register ByteCode *codePtr; /* The bytecode whose summary is printed
				 * to stdout. */
    unsigned char *pc;		/* Points to first byte of a bytecode
				 * instruction. The program counter. */
    int stackTop;		/* Current stack top. Must be between
				 * stackLowerBound and stackUpperBound
				 * (inclusive). */
    int stackLowerBound;	/* Smallest legal value for stackTop. */
{
    int stackUpperBound = stackLowerBound +  codePtr->maxStackDepth;	
                                /* Greatest legal value for stackTop. */
    unsigned int relativePc = (unsigned int) (pc - codePtr->codeStart);
    unsigned int codeStart = (unsigned int) codePtr->codeStart;
    unsigned int codeEnd = (unsigned int)
	    (codePtr->codeStart + codePtr->numCodeBytes);
    unsigned char opCode = *pc;

    if (((unsigned int) pc < codeStart) || ((unsigned int) pc > codeEnd)) {
	fprintf(stderr, "\nBad instruction pc 0x%x in TclExecuteByteCode\n",
		(unsigned int) pc);
	panic("TclExecuteByteCode execution failure: bad pc");
    }
    if ((unsigned int) opCode > LAST_INST_OPCODE) {
	fprintf(stderr, "\nBad opcode %d at pc %u in TclExecuteByteCode\n",
		(unsigned int) opCode, relativePc);
        panic("TclExecuteByteCode execution failure: bad opcode");
    }
    if ((stackTop < stackLowerBound) || (stackTop > stackUpperBound)) {
	int numChars;
	char *cmd = GetSrcInfoForPc(pc, codePtr, &numChars);
	char *ellipsis = "";
	
	fprintf(stderr, "\nBad stack top %d at pc %u in TclExecuteByteCode (min %i, max %i)",
		stackTop, relativePc, stackLowerBound, stackUpperBound);
	if (cmd != NULL) {
	    if (numChars > 100) {
		numChars = 100;
		ellipsis = "...";
	    }
	    fprintf(stderr, "\n executing %.*s%s\n", numChars, cmd,
		    ellipsis);
	} else {
	    fprintf(stderr, "\n");
	}
	panic("TclExecuteByteCode execution failure: bad stack top");
    }
}
#endif /* TCL_COMPILE_DEBUG */

/*
 *----------------------------------------------------------------------
 *
 * IllegalExprOperandType --
 *
 *	Used by TclExecuteByteCode to add an error message to errorInfo
 *	when an illegal operand type is detected by an expression
 *	instruction. The argument opndPtr holds the operand object in error.
 *
 * Results:
 *	None.
 *
 * Side effects:
 *	An error message is appended to errorInfo.
 *
 *----------------------------------------------------------------------
 */

static void
IllegalExprOperandType(interp, pc, opndPtr)
    Tcl_Interp *interp;		/* Interpreter to which error information
				 * pertains. */
    unsigned char *pc;		/* Points to the instruction being executed
				 * when the illegal type was found. */
    Tcl_Obj *opndPtr;		/* Points to the operand holding the value
				 * with the illegal type. */
{
    unsigned char opCode = *pc;
    
    Tcl_ResetResult(interp);
    if ((opndPtr->bytes == NULL) || (opndPtr->length == 0)) {
	Tcl_AppendStringsToObj(Tcl_GetObjResult(interp),
		"can't use empty string as operand of \"",
		operatorStrings[opCode - INST_LOR], "\"", (char *) NULL);
    } else {
	char *msg = "non-numeric string";
	char *s, *p;
	int length;
	int looksLikeInt = 0;

	s = Tcl_GetStringFromObj(opndPtr, &length);
	p = s;
	/*
	 * strtod() isn't at all consistent about detecting Inf and
	 * NaN between platforms.
	 */
	if (length == 3) {
	    if ((s[0]=='n' || s[0]=='N') && (s[1]=='a' || s[1]=='A') &&
		    (s[2]=='n' || s[2]=='N')) {
		msg = "non-numeric floating-point value";
		goto makeErrorMessage;
	    }
	    if ((s[0]=='i' || s[0]=='I') && (s[1]=='n' || s[1]=='N') &&
		    (s[2]=='f' || s[2]=='F')) {
		msg = "infinite floating-point value";
		goto makeErrorMessage;
	    }
	}

	/*
	 * We cannot use TclLooksLikeInt here because it passes strings
	 * like "10;" [Bug 587140]. We'll accept as "looking like ints"
	 * for the present purposes any string that looks formally like
	 * a (decimal|octal|hex) integer.
	 */

	while (length && isspace(UCHAR(*p))) {
	    length--;
	    p++;
	}
	if (length && ((*p == '+') || (*p == '-'))) {
	    length--;
	    p++;
	}
	if (length) {
	    if ((*p == '0') && ((*(p+1) == 'x') || (*(p+1) == 'X'))) {
		p += 2;
		length -= 2;
		looksLikeInt = ((length > 0) && isxdigit(UCHAR(*p)));
		if (looksLikeInt) {
		    length--;
		    p++;
		    while (length && isxdigit(UCHAR(*p))) {
			length--;
			p++;
		    }
		}
	    } else {
		looksLikeInt = (length && isdigit(UCHAR(*p)));
		if (looksLikeInt) {
		    length--;
		    p++;
		    while (length && isdigit(UCHAR(*p))) {
			length--;
			p++;
		    }
		}
	    }
	    while (length && isspace(UCHAR(*p))) {
		length--;
		p++;
	    }
	    looksLikeInt = !length;
	}
	if (looksLikeInt) {
	    /*
	     * If something that looks like an integer could not be
	     * converted, then it *must* be a bad octal or too large
	     * to represent [Bug 542588].
	     */

	    if (TclCheckBadOctal(NULL, s)) {
		msg = "invalid octal number";
	    } else {
		msg = "integer value too large to represent";
		Tcl_SetErrorCode(interp, "ARITH", "IOVERFLOW",
		    "integer value too large to represent", (char *) NULL);
	    }
	} else {
	    /*
	     * See if the operand can be interpreted as a double in
	     * order to improve the error message.
	     */

	    double d;

	    if (Tcl_GetDouble((Tcl_Interp *) NULL, s, &d) == TCL_OK) {
		msg = "floating-point value";
	    }
	}
      makeErrorMessage:
	Tcl_AppendStringsToObj(Tcl_GetObjResult(interp), "can't use ",
		msg, " as operand of \"", operatorStrings[opCode - INST_LOR],
		"\"", (char *) NULL);
    }
}

/*
 *----------------------------------------------------------------------
 *
 * GetSrcInfoForPc --
 *
 *	Given a program counter value, finds the closest command in the
 *	bytecode code unit's CmdLocation array and returns information about
 *	that command's source: a pointer to its first byte and the number of
 *	characters.
 *
 * Results:
 *	If a command is found that encloses the program counter value, a
 *	pointer to the command's source is returned and the length of the
 *	source is stored at *lengthPtr. If multiple commands resulted in
 *	code at pc, information about the closest enclosing command is
 *	returned. If no matching command is found, NULL is returned and
 *	*lengthPtr is unchanged.
 *
 * Side effects:
 *	None.
 *
 *----------------------------------------------------------------------
 */

static char *
GetSrcInfoForPc(pc, codePtr, lengthPtr)
    unsigned char *pc;		/* The program counter value for which to
				 * return the closest command's source info.
				 * This points to a bytecode instruction
				 * in codePtr's code. */
    ByteCode *codePtr;		/* The bytecode sequence in which to look
				 * up the command source for the pc. */
    int *lengthPtr;		/* If non-NULL, the location where the
				 * length of the command's source should be
				 * stored. If NULL, no length is stored. */
{
    register int pcOffset = (pc - codePtr->codeStart);
    int numCmds = codePtr->numCommands;
    unsigned char *codeDeltaNext, *codeLengthNext;
    unsigned char *srcDeltaNext, *srcLengthNext;
    int codeOffset, codeLen, codeEnd, srcOffset, srcLen, delta, i;
    int bestDist = INT_MAX;	/* Distance of pc to best cmd's start pc. */
    int bestSrcOffset = -1;	/* Initialized to avoid compiler warning. */
    int bestSrcLength = -1;	/* Initialized to avoid compiler warning. */

    if ((pcOffset < 0) || (pcOffset >= codePtr->numCodeBytes)) {
	return NULL;
    }

    /*
     * Decode the code and source offset and length for each command. The
     * closest enclosing command is the last one whose code started before
     * pcOffset.
     */

    codeDeltaNext = codePtr->codeDeltaStart;
    codeLengthNext = codePtr->codeLengthStart;
    srcDeltaNext  = codePtr->srcDeltaStart;
    srcLengthNext = codePtr->srcLengthStart;
    codeOffset = srcOffset = 0;
    for (i = 0;  i < numCmds;  i++) {
	if ((unsigned int) (*codeDeltaNext) == (unsigned int) 0xFF) {
	    codeDeltaNext++;
	    delta = TclGetInt4AtPtr(codeDeltaNext);
	    codeDeltaNext += 4;
	} else {
	    delta = TclGetInt1AtPtr(codeDeltaNext);
	    codeDeltaNext++;
	}
	codeOffset += delta;

	if ((unsigned int) (*codeLengthNext) == (unsigned int) 0xFF) {
	    codeLengthNext++;
	    codeLen = TclGetInt4AtPtr(codeLengthNext);
	    codeLengthNext += 4;
	} else {
	    codeLen = TclGetInt1AtPtr(codeLengthNext);
	    codeLengthNext++;
	}
	codeEnd = (codeOffset + codeLen - 1);

	if ((unsigned int) (*srcDeltaNext) == (unsigned int) 0xFF) {
	    srcDeltaNext++;
	    delta = TclGetInt4AtPtr(srcDeltaNext);
	    srcDeltaNext += 4;
	} else {
	    delta = TclGetInt1AtPtr(srcDeltaNext);
	    srcDeltaNext++;
	}
	srcOffset += delta;

	if ((unsigned int) (*srcLengthNext) == (unsigned int) 0xFF) {
	    srcLengthNext++;
	    srcLen = TclGetInt4AtPtr(srcLengthNext);
	    srcLengthNext += 4;
	} else {
	    srcLen = TclGetInt1AtPtr(srcLengthNext);
	    srcLengthNext++;
	}
	
	if (codeOffset > pcOffset) {      /* best cmd already found */
	    break;
	} else if (pcOffset <= codeEnd) { /* this cmd's code encloses pc */
	    int dist = (pcOffset - codeOffset);
	    if (dist <= bestDist) {
		bestDist = dist;
		bestSrcOffset = srcOffset;
		bestSrcLength = srcLen;
	    }
	}
    }

    if (bestDist == INT_MAX) {
	return NULL;
    }
    
    if (lengthPtr != NULL) {
	*lengthPtr = bestSrcLength;
    }
    return (codePtr->source + bestSrcOffset);
}

/*
 *----------------------------------------------------------------------
 *
 * GetExceptRangeForPc --
 *
 *	Given a program counter value, return the closest enclosing
 *	ExceptionRange.
 *
 * Results:
 *	In the normal case, catchOnly is 0 (false) and this procedure
 *	returns a pointer to the most closely enclosing ExceptionRange
 *	structure regardless of whether it is a loop or catch exception
 *	range. This is appropriate when processing a TCL_BREAK or
 *	TCL_CONTINUE, which will be "handled" either by a loop exception
 *	range or a closer catch range. If catchOnly is nonzero, this
 *	procedure ignores loop exception ranges and returns a pointer to the
 *	closest catch range. If no matching ExceptionRange is found that
 *	encloses pc, a NULL is returned.
 *
 * Side effects:
 *	None.
 *
 *----------------------------------------------------------------------
 */

static ExceptionRange *
GetExceptRangeForPc(pc, catchOnly, codePtr)
    unsigned char *pc;		/* The program counter value for which to
				 * search for a closest enclosing exception
				 * range. This points to a bytecode
				 * instruction in codePtr's code. */
    int catchOnly;		/* If 0, consider either loop or catch
				 * ExceptionRanges in search. If nonzero
				 * consider only catch ranges (and ignore
				 * any closer loop ranges). */
    ByteCode* codePtr;		/* Points to the ByteCode in which to search
				 * for the enclosing ExceptionRange. */
{
    ExceptionRange *rangeArrayPtr;
    int numRanges = codePtr->numExceptRanges;
    register ExceptionRange *rangePtr;
    int pcOffset = (pc - codePtr->codeStart);
    register int start;

    if (numRanges == 0) {
	return NULL;
    }

    /* 
     * This exploits peculiarities of our compiler: nested ranges
     * are always *after* their containing ranges, so that by scanning
     * backwards we are sure that the first matching range is indeed
     * the deepest.
     */

    rangeArrayPtr = codePtr->exceptArrayPtr;
    rangePtr = rangeArrayPtr + numRanges;
    while (--rangePtr >= rangeArrayPtr) {
	start = rangePtr->codeOffset;
	if ((start <= pcOffset) &&
	        (pcOffset < (start + rangePtr->numCodeBytes))) {
	    if ((!catchOnly)
		    || (rangePtr->type == CATCH_EXCEPTION_RANGE)) {
		return rangePtr;
	    }
	}
    }
    return NULL;
}

/*
 *----------------------------------------------------------------------
 *
 * GetOpcodeName --
 *
 *	This procedure is called by the TRACE and TRACE_WITH_OBJ macros
 *	used in TclExecuteByteCode when debugging. It returns the name of
 *	the bytecode instruction at a specified instruction pc.
 *
 * Results:
 *	A character string for the instruction.
 *
 * Side effects:
 *	None.
 *
 *----------------------------------------------------------------------
 */

#ifdef TCL_COMPILE_DEBUG
static char *
GetOpcodeName(pc)
    unsigned char *pc;		/* Points to the instruction whose name
				 * should be returned. */
{
    unsigned char opCode = *pc;
    
    return tclInstructionTable[opCode].name;
}
#endif /* TCL_COMPILE_DEBUG */

/*
 *----------------------------------------------------------------------
 *
 * VerifyExprObjType --
 *
 *	This procedure is called by the math functions to verify that
 *	the object is either an int or double, coercing it if necessary.
 *	If an error occurs during conversion, an error message is left
 *	in the interpreter's result unless "interp" is NULL.
 *
 * Results:
 *	TCL_OK if it was int or double, TCL_ERROR otherwise
 *
 * Side effects:
 *	objPtr is ensured to be of tclIntType, tclWideIntType or
 *	tclDoubleType.
 *
 *----------------------------------------------------------------------
 */

static int
VerifyExprObjType(interp, objPtr)
    Tcl_Interp *interp;		/* The interpreter in which to execute the
				 * function. */
    Tcl_Obj *objPtr;		/* Points to the object to type check. */
{
    if (IS_NUMERIC_TYPE(objPtr->typePtr)) {
	return TCL_OK;
    } else {
	int length, result = TCL_OK;
	char *s = Tcl_GetStringFromObj(objPtr, &length);
	
	if (TclLooksLikeInt(s, length)) {
	    long i;
	    Tcl_WideInt w;
	    GET_WIDE_OR_INT(result, objPtr, i, w);
	} else {
	    double d;
	    result = Tcl_GetDoubleFromObj((Tcl_Interp *) NULL, objPtr, &d);
	}
	if ((result != TCL_OK) && (interp != NULL)) {
	    Tcl_ResetResult(interp);
	    if (TclCheckBadOctal((Tcl_Interp *) NULL, s)) {
		Tcl_AppendToObj(Tcl_GetObjResult(interp),
			"argument to math function was an invalid octal number",
			-1);
	    } else {
		Tcl_AppendToObj(Tcl_GetObjResult(interp),
			"argument to math function didn't have numeric value",
			-1);
	    }
	}
	return result;
    }
}

/*
 *----------------------------------------------------------------------
 *
 * Math Functions --
 *
 *	This page contains the procedures that implement all of the
 *	built-in math functions for expressions.
 *
 * Results:
 *	Each procedure returns TCL_OK if it succeeds and pushes an
 *	Tcl object holding the result. If it fails it returns TCL_ERROR
 *	and leaves an error message in the interpreter's result.
 *
 * Side effects:
 *	None.
 *
 *----------------------------------------------------------------------
 */

static int
ExprUnaryFunc(interp, eePtr, clientData)
    Tcl_Interp *interp;		/* The interpreter in which to execute the
				 * function. */
    ExecEnv *eePtr;		/* Points to the environment for executing
				 * the function. */
    ClientData clientData;	/* Contains the address of a procedure that
				 * takes one double argument and returns a
				 * double result. */
{
    Tcl_Obj **stackPtr;		/* Cached evaluation stack base pointer. */
    register int stackTop;	/* Cached top index of evaluation stack. */
    register Tcl_Obj *valuePtr;
    double d, dResult;
    int result;
    
    double (*func) _ANSI_ARGS_((double)) =
	(double (*)_ANSI_ARGS_((double))) clientData;

    /*
     * Set stackPtr and stackTop from eePtr.
     */

    result = TCL_OK;
    CACHE_STACK_INFO();

    /*
     * Pop the function's argument from the evaluation stack. Convert it
     * to a double if necessary.
     */

    valuePtr = POP_OBJECT();

    if (VerifyExprObjType(interp, valuePtr) != TCL_OK) {
	result = TCL_ERROR;
	goto done;
    }

    GET_DOUBLE_VALUE(d, valuePtr, valuePtr->typePtr);

    errno = 0;
    dResult = (*func)(d);
    if ((errno != 0) || IS_NAN(dResult) || IS_INF(dResult)) {
	TclExprFloatError(interp, dResult);
	result = TCL_ERROR;
	goto done;
    }
    
    /*
     * Push a Tcl object holding the result.
     */

    PUSH_OBJECT(Tcl_NewDoubleObj(dResult));
    
    /*
     * Reflect the change to stackTop back in eePtr.
     */

    done:
    TclDecrRefCount(valuePtr);
    DECACHE_STACK_INFO();
    return result;
}

static int
ExprBinaryFunc(interp, eePtr, clientData)
    Tcl_Interp *interp;		/* The interpreter in which to execute the
				 * function. */
    ExecEnv *eePtr;		/* Points to the environment for executing
				 * the function. */
    ClientData clientData;	/* Contains the address of a procedure that
				 * takes two double arguments and
				 * returns a double result. */
{
    Tcl_Obj **stackPtr;        /* Cached evaluation stack base pointer. */
    register int stackTop;	/* Cached top index of evaluation stack. */
    register Tcl_Obj *valuePtr, *value2Ptr;
    double d1, d2, dResult;
    int result;
    
    double (*func) _ANSI_ARGS_((double, double))
	= (double (*)_ANSI_ARGS_((double, double))) clientData;

    /*
     * Set stackPtr and stackTop from eePtr.
     */

    result = TCL_OK;
    CACHE_STACK_INFO();

    /*
     * Pop the function's two arguments from the evaluation stack. Convert
     * them to doubles if necessary.
     */

    value2Ptr = POP_OBJECT();
    valuePtr  = POP_OBJECT();

    if ((VerifyExprObjType(interp, valuePtr) != TCL_OK) ||
	    (VerifyExprObjType(interp, value2Ptr) != TCL_OK)) {
	result = TCL_ERROR;
	goto done;
    }

    GET_DOUBLE_VALUE(d1, valuePtr, valuePtr->typePtr);
    GET_DOUBLE_VALUE(d2, value2Ptr, value2Ptr->typePtr);

    errno = 0;
    dResult = (*func)(d1, d2);
    if ((errno != 0) || IS_NAN(dResult) || IS_INF(dResult)) {
	TclExprFloatError(interp, dResult);
	result = TCL_ERROR;
	goto done;
    }

    /*
     * Push a Tcl object holding the result.
     */

    PUSH_OBJECT(Tcl_NewDoubleObj(dResult));
    
    /*
     * Reflect the change to stackTop back in eePtr.
     */

    done:
    TclDecrRefCount(valuePtr);
    TclDecrRefCount(value2Ptr);
    DECACHE_STACK_INFO();
    return result;
}

static int
ExprAbsFunc(interp, eePtr, clientData)
    Tcl_Interp *interp;		/* The interpreter in which to execute the
				 * function. */
    ExecEnv *eePtr;		/* Points to the environment for executing
				 * the function. */
    ClientData clientData;	/* Ignored. */
{
    Tcl_Obj **stackPtr;        /* Cached evaluation stack base pointer. */
    register int stackTop;	/* Cached top index of evaluation stack. */
    register Tcl_Obj *valuePtr;
    long i, iResult;
    double d, dResult;
    int result;

    /*
     * Set stackPtr and stackTop from eePtr.
     */

    result = TCL_OK;
    CACHE_STACK_INFO();

    /*
     * Pop the argument from the evaluation stack.
     */

    valuePtr = POP_OBJECT();

    if (VerifyExprObjType(interp, valuePtr) != TCL_OK) {
	result = TCL_ERROR;
	goto done;
    }

    /*
     * Push a Tcl object with the result.
     */
    if (valuePtr->typePtr == &tclIntType) {
	i = valuePtr->internalRep.longValue;
	if (i < 0) {
	    iResult = -i;
	    if (iResult < 0) {
		Tcl_ResetResult(interp);
		Tcl_AppendToObj(Tcl_GetObjResult(interp),
		        "integer value too large to represent", -1);
		Tcl_SetErrorCode(interp, "ARITH", "IOVERFLOW",
			"integer value too large to represent", (char *) NULL);
		result = TCL_ERROR;
		goto done;
	    }
	} else {
	    iResult = i;
	}	    
	PUSH_OBJECT(Tcl_NewLongObj(iResult));
    } else if (valuePtr->typePtr == &tclWideIntType) {
	Tcl_WideInt wResult, w;
	TclGetWide(w,valuePtr);
	if (w < W0) {
	    wResult = -w;
	    if (wResult < 0) {
		Tcl_ResetResult(interp);
		Tcl_AppendToObj(Tcl_GetObjResult(interp),
		        "integer value too large to represent", -1);
		Tcl_SetErrorCode(interp, "ARITH", "IOVERFLOW",
			"integer value too large to represent", (char *) NULL);
		result = TCL_ERROR;
		goto done;
	    }
	} else {
	    wResult = w;
	}	    
	PUSH_OBJECT(Tcl_NewWideIntObj(wResult));
    } else {
	d = valuePtr->internalRep.doubleValue;
	if (d < 0.0) {
	    dResult = -d;
	} else {
	    dResult = d;
	}
	if (IS_NAN(dResult) || IS_INF(dResult)) {
	    TclExprFloatError(interp, dResult);
	    result = TCL_ERROR;
	    goto done;
	}
	PUSH_OBJECT(Tcl_NewDoubleObj(dResult));
    }

    /*
     * Reflect the change to stackTop back in eePtr.
     */

    done:
    TclDecrRefCount(valuePtr);
    DECACHE_STACK_INFO();
    return result;
}

static int
ExprDoubleFunc(interp, eePtr, clientData)
    Tcl_Interp *interp;		/* The interpreter in which to execute the
				 * function. */
    ExecEnv *eePtr;		/* Points to the environment for executing
				 * the function. */
    ClientData clientData;	/* Ignored. */
{
    Tcl_Obj **stackPtr;        /* Cached evaluation stack base pointer. */
    register int stackTop;	/* Cached top index of evaluation stack. */
    register Tcl_Obj *valuePtr;
    double dResult;
    int result;

    /*
     * Set stackPtr and stackTop from eePtr.
     */

    result = TCL_OK;
    CACHE_STACK_INFO();

    /*
     * Pop the argument from the evaluation stack.
     */

    valuePtr = POP_OBJECT();

    if (VerifyExprObjType(interp, valuePtr) != TCL_OK) {
	result = TCL_ERROR;
	goto done;
    }

    GET_DOUBLE_VALUE(dResult, valuePtr, valuePtr->typePtr);

    /*
     * Push a Tcl object with the result.
     */

    PUSH_OBJECT(Tcl_NewDoubleObj(dResult));

    /*
     * Reflect the change to stackTop back in eePtr.
     */

    done:
    TclDecrRefCount(valuePtr);
    DECACHE_STACK_INFO();
    return result;
}

static int
ExprIntFunc(interp, eePtr, clientData)
    Tcl_Interp *interp;		/* The interpreter in which to execute the
				 * function. */
    ExecEnv *eePtr;		/* Points to the environment for executing
				 * the function. */
    ClientData clientData;	/* Ignored. */
{
    Tcl_Obj **stackPtr;        /* Cached evaluation stack base pointer. */
    register int stackTop;	/* Cached top index of evaluation stack. */
    register Tcl_Obj *valuePtr;
    long iResult;
    double d;
    int result;

    /*
     * Set stackPtr and stackTop from eePtr.
     */

    result = TCL_OK;
    CACHE_STACK_INFO();

    /*
     * Pop the argument from the evaluation stack.
     */

    valuePtr = POP_OBJECT();
    
    if (VerifyExprObjType(interp, valuePtr) != TCL_OK) {
	result = TCL_ERROR;
	goto done;
    }
    
    if (valuePtr->typePtr == &tclIntType) {
	iResult = valuePtr->internalRep.longValue;
    } else if (valuePtr->typePtr == &tclWideIntType) {
	TclGetLongFromWide(iResult,valuePtr);
    } else {
	d = valuePtr->internalRep.doubleValue;
	if (d < 0.0) {
	    if (d < (double) (long) LONG_MIN) {
		tooLarge:
		Tcl_ResetResult(interp);
		Tcl_AppendToObj(Tcl_GetObjResult(interp),
		        "integer value too large to represent", -1);
		Tcl_SetErrorCode(interp, "ARITH", "IOVERFLOW",
			"integer value too large to represent", (char *) NULL);
		result = TCL_ERROR;
		goto done;
	    }
	} else {
	    if (d > (double) LONG_MAX) {
		goto tooLarge;
	    }
	}
	if (IS_NAN(d) || IS_INF(d)) {
	    TclExprFloatError(interp, d);
	    result = TCL_ERROR;
	    goto done;
	}
	iResult = (long) d;
    }

    /*
     * Push a Tcl object with the result.
     */
    
    PUSH_OBJECT(Tcl_NewLongObj(iResult));

    /*
     * Reflect the change to stackTop back in eePtr.
     */

    done:
    TclDecrRefCount(valuePtr);
    DECACHE_STACK_INFO();
    return result;
}

static int
ExprWideFunc(interp, eePtr, clientData)
    Tcl_Interp *interp;		/* The interpreter in which to execute the
				 * function. */
    ExecEnv *eePtr;		/* Points to the environment for executing
				 * the function. */
    ClientData clientData;	/* Ignored. */
{
    Tcl_Obj **stackPtr;        /* Cached evaluation stack base pointer. */
    register int stackTop;	/* Cached top index of evaluation stack. */
    register Tcl_Obj *valuePtr;
    Tcl_WideInt wResult;
    double d;
    int result;

    /*
     * Set stackPtr and stackTop from eePtr.
     */

    result = TCL_OK;
    CACHE_STACK_INFO();

    /*
     * Pop the argument from the evaluation stack.
     */

    valuePtr = POP_OBJECT();
    
    if (VerifyExprObjType(interp, valuePtr) != TCL_OK) {
	result = TCL_ERROR;
	goto done;
    }
    
    if (valuePtr->typePtr == &tclWideIntType) {
	TclGetWide(wResult,valuePtr);
    } else if (valuePtr->typePtr == &tclIntType) {
	wResult = Tcl_LongAsWide(valuePtr->internalRep.longValue);
    } else {
	d = valuePtr->internalRep.doubleValue;
	if (d < 0.0) {
	    if (d < Tcl_WideAsDouble(LLONG_MIN)) {
		tooLarge:
		Tcl_ResetResult(interp);
		Tcl_AppendToObj(Tcl_GetObjResult(interp),
		        "integer value too large to represent", -1);
		Tcl_SetErrorCode(interp, "ARITH", "IOVERFLOW",
			"integer value too large to represent", (char *) NULL);
		result = TCL_ERROR;
		goto done;
	    }
	} else {
	    if (d > Tcl_WideAsDouble(LLONG_MAX)) {
		goto tooLarge;
	    }
	}
	if (IS_NAN(d) || IS_INF(d)) {
	    TclExprFloatError(interp, d);
	    result = TCL_ERROR;
	    goto done;
	}
	wResult = Tcl_DoubleAsWide(d);
    }

    /*
     * Push a Tcl object with the result.
     */
    
    PUSH_OBJECT(Tcl_NewWideIntObj(wResult));

    /*
     * Reflect the change to stackTop back in eePtr.
     */

    done:
    TclDecrRefCount(valuePtr);
    DECACHE_STACK_INFO();
    return result;
}

static int
ExprRandFunc(interp, eePtr, clientData)
    Tcl_Interp *interp;		/* The interpreter in which to execute the
				 * function. */
    ExecEnv *eePtr;		/* Points to the environment for executing
				 * the function. */
    ClientData clientData;	/* Ignored. */
{
    Tcl_Obj **stackPtr;        /* Cached evaluation stack base pointer. */
    register int stackTop;	/* Cached top index of evaluation stack. */
    Interp *iPtr = (Interp *) interp;
    double dResult;
    long tmp;			/* Algorithm assumes at least 32 bits.
				 * Only long guarantees that.  See below. */

    if (!(iPtr->flags & RAND_SEED_INITIALIZED)) {
	iPtr->flags |= RAND_SEED_INITIALIZED;
        
        /* 
	 * Take into consideration the thread this interp is running in order
	 * to insure different seeds in different threads (bug #416643)
	 */

	iPtr->randSeed = TclpGetClicks() + ((long)Tcl_GetCurrentThread()<<12);

	/*
	 * Make sure 1 <= randSeed <= (2^31) - 2.  See below.
	 */

        iPtr->randSeed &= (unsigned long) 0x7fffffff;
	if ((iPtr->randSeed == 0) || (iPtr->randSeed == 0x7fffffff)) {
	    iPtr->randSeed ^= 123459876;
	}
    }
    
    /*
     * Set stackPtr and stackTop from eePtr.
     */
    
    CACHE_STACK_INFO();

    /*
     * Generate the random number using the linear congruential
     * generator defined by the following recurrence:
     *		seed = ( IA * seed ) mod IM
     * where IA is 16807 and IM is (2^31) - 1.  The recurrence maps
     * a seed in the range [1, IM - 1] to a new seed in that same range.
     * The recurrence maps IM to 0, and maps 0 back to 0, so those two
     * values must not be allowed as initial values of seed.
     *
     * In order to avoid potential problems with integer overflow, the
     * recurrence is implemented in terms of additional constants
     * IQ and IR such that
     *		IM = IA*IQ + IR
     * None of the operations in the implementation overflows a 32-bit
     * signed integer, and the C type long is guaranteed to be at least
     * 32 bits wide.
     *
     * For more details on how this algorithm works, refer to the following
     * papers: 
     *
     *	S.K. Park & K.W. Miller, "Random number generators: good ones
     *	are hard to find," Comm ACM 31(10):1192-1201, Oct 1988
     *
     *	W.H. Press & S.A. Teukolsky, "Portable random number
     *	generators," Computers in Physics 6(5):522-524, Sep/Oct 1992.
     */

#define RAND_IA		16807
#define RAND_IM		2147483647
#define RAND_IQ		127773
#define RAND_IR		2836
#define RAND_MASK	123459876

    tmp = iPtr->randSeed/RAND_IQ;
    iPtr->randSeed = RAND_IA*(iPtr->randSeed - tmp*RAND_IQ) - RAND_IR*tmp;
    if (iPtr->randSeed < 0) {
	iPtr->randSeed += RAND_IM;
    }

    /*
     * Since the recurrence keeps seed values in the range [1, RAND_IM - 1],
     * dividing by RAND_IM yields a double in the range (0, 1).
     */

    dResult = iPtr->randSeed * (1.0/RAND_IM);

    /*
     * Push a Tcl object with the result.
     */

    PUSH_OBJECT(Tcl_NewDoubleObj(dResult));
    
    /*
     * Reflect the change to stackTop back in eePtr.
     */

    DECACHE_STACK_INFO();
    return TCL_OK;
}

static int
ExprRoundFunc(interp, eePtr, clientData)
    Tcl_Interp *interp;		/* The interpreter in which to execute the
				 * function. */
    ExecEnv *eePtr;		/* Points to the environment for executing
				 * the function. */
    ClientData clientData;	/* Ignored. */
{
    Tcl_Obj **stackPtr;        /* Cached evaluation stack base pointer. */
    register int stackTop;	/* Cached top index of evaluation stack. */
    Tcl_Obj *valuePtr, *resPtr;
    double d;
    int result;

    /*
     * Set stackPtr and stackTop from eePtr.
     */

    result = TCL_OK;
    CACHE_STACK_INFO();

    /*
     * Pop the argument from the evaluation stack.
     */

    valuePtr = POP_OBJECT();

    if (VerifyExprObjType(interp, valuePtr) != TCL_OK) {
	result = TCL_ERROR;
	goto done;
    }

    if ((valuePtr->typePtr == &tclIntType) ||
	    (valuePtr->typePtr == &tclWideIntType)) {
	result = TCL_OK;
	resPtr = valuePtr;
    } else {
	d = valuePtr->internalRep.doubleValue;
	if (d < 0.0) {
	    if (d <= Tcl_WideAsDouble(LLONG_MIN)-0.5) {
		goto tooLarge;
	    } else if (d <= (((double) (long) LONG_MIN) - 0.5)) {
		resPtr = Tcl_NewWideIntObj(Tcl_DoubleAsWide(d - 0.5));
	    } else {
		resPtr = Tcl_NewLongObj((long) (d - 0.5));
	    }			    
	} else {
	    if (d >= Tcl_WideAsDouble(LLONG_MAX)+0.5) {
		goto tooLarge;
	    } else if (d >= (((double) LONG_MAX + 0.5))) {
		resPtr = Tcl_NewWideIntObj(Tcl_DoubleAsWide(d + 0.5));
	    } else {
		resPtr = Tcl_NewLongObj((long) (d + 0.5));
	    }
	}
    }

    /*
     * Push the result object and free the argument Tcl_Obj.
     */

    PUSH_OBJECT(resPtr);
    
    done:
    TclDecrRefCount(valuePtr);
    DECACHE_STACK_INFO();
    return result;

    /*
     * Error return: result cannot be represented as an integer.
     */
    
    tooLarge:
    Tcl_ResetResult(interp);
    Tcl_AppendToObj(Tcl_GetObjResult(interp),
	    "integer value too large to represent", -1);
    Tcl_SetErrorCode(interp, "ARITH", "IOVERFLOW",
	    "integer value too large to represent",
	    (char *) NULL);
    result = TCL_ERROR;
    goto done;
}

static int
ExprSrandFunc(interp, eePtr, clientData)
    Tcl_Interp *interp;		/* The interpreter in which to execute the
				 * function. */
    ExecEnv *eePtr;		/* Points to the environment for executing
				 * the function. */
    ClientData clientData;	/* Ignored. */
{
    Tcl_Obj **stackPtr;        /* Cached evaluation stack base pointer. */
    register int stackTop;	/* Cached top index of evaluation stack. */
    Interp *iPtr = (Interp *) interp;
    Tcl_Obj *valuePtr;
    long i = 0;			/* Initialized to avoid compiler warning. */

    /*
     * Set stackPtr and stackTop from eePtr.
     */
    
    CACHE_STACK_INFO();

    /*
     * Pop the argument from the evaluation stack.  Use the value
     * to reset the random number seed.
     */

    valuePtr = POP_OBJECT();

    if (VerifyExprObjType(interp, valuePtr) != TCL_OK) {
	goto badValue;
    }

    if (valuePtr->typePtr == &tclIntType) {
	i = valuePtr->internalRep.longValue;
    } else if (valuePtr->typePtr == &tclWideIntType) {
	TclGetLongFromWide(i,valuePtr);
    } else {
	/*
	 * At this point, the only other possible type is double
	 */
	Tcl_ResetResult(interp);
	Tcl_AppendStringsToObj(Tcl_GetObjResult(interp),
		"can't use floating-point value as argument to srand",
		(char *) NULL);
	badValue:
	TclDecrRefCount(valuePtr);
	DECACHE_STACK_INFO();
	return TCL_ERROR;
    }
    
    /*
     * Reset the seed.  Make sure 1 <= randSeed <= 2^31 - 2.
     * See comments in ExprRandFunc() for more details.
     */

    iPtr->flags |= RAND_SEED_INITIALIZED;
    iPtr->randSeed = i;
    iPtr->randSeed &= (unsigned long) 0x7fffffff;
    if ((iPtr->randSeed == 0) || (iPtr->randSeed == 0x7fffffff)) {
	iPtr->randSeed ^= 123459876;
    }

    /*
     * To avoid duplicating the random number generation code we simply
     * clean up our state and call the real random number function. That
     * function will always succeed.
     */
    
    TclDecrRefCount(valuePtr);
    DECACHE_STACK_INFO();

    ExprRandFunc(interp, eePtr, clientData);
    return TCL_OK;
}

/*
 *----------------------------------------------------------------------
 *
 * ExprCallMathFunc --
 *
 *	This procedure is invoked to call a non-builtin math function
 *	during the execution of an expression. 
 *
 * Results:
 *	TCL_OK is returned if all went well and the function's value
 *	was computed successfully. If an error occurred, TCL_ERROR
 *	is returned and an error message is left in the interpreter's
 *	result.	After a successful return this procedure pushes a Tcl object
 *	holding the result. 
 *
 * Side effects:
 *	None, unless the called math function has side effects.
 *
 *----------------------------------------------------------------------
 */

static int
ExprCallMathFunc(interp, eePtr, objc, objv)
    Tcl_Interp *interp;		/* The interpreter in which to execute the
				 * function. */
    ExecEnv *eePtr;		/* Points to the environment for executing
				 * the function. */
    int objc;			/* Number of arguments. The function name is
				 * the 0-th argument. */
    Tcl_Obj **objv;		/* The array of arguments. The function name
				 * is objv[0]. */
{
    Interp *iPtr = (Interp *) interp;
    Tcl_Obj **stackPtr;		/* Cached evaluation stack base pointer. */
    register int stackTop;	/* Cached top index of evaluation stack. */
    char *funcName;
    Tcl_HashEntry *hPtr;
    MathFunc *mathFuncPtr;	/* Information about math function. */
    Tcl_Value args[MAX_MATH_ARGS]; /* Arguments for function call. */
    Tcl_Value funcResult;	/* Result of function call as Tcl_Value. */
    register Tcl_Obj *valuePtr;
    long i;
    double d;
    int j, k, result;

    Tcl_ResetResult(interp);

    /*
     * Set stackPtr and stackTop from eePtr.
     */
    
    CACHE_STACK_INFO();

    /*
     * Look up the MathFunc record for the function.
     */

    funcName = TclGetString(objv[0]);
    hPtr = Tcl_FindHashEntry(&iPtr->mathFuncTable, funcName);
    if (hPtr == NULL) {
	Tcl_AppendStringsToObj(Tcl_GetObjResult(interp),
		"unknown math function \"", funcName, "\"", (char *) NULL);
	result = TCL_ERROR;
	goto done;
    }
    mathFuncPtr = (MathFunc *) Tcl_GetHashValue(hPtr);
    if (mathFuncPtr->numArgs != (objc-1)) {
	panic("ExprCallMathFunc: expected number of args %d != actual number %d",
	        mathFuncPtr->numArgs, objc);
	result = TCL_ERROR;
	goto done;
    }

    /*
     * Collect the arguments for the function, if there are any, into the
     * array "args". Note that args[0] will have the Tcl_Value that
     * corresponds to objv[1].
     */

    for (j = 1, k = 0;  j < objc;  j++, k++) {
	valuePtr = objv[j];

	if (VerifyExprObjType(interp, valuePtr) != TCL_OK) {
	    result = TCL_ERROR;
	    goto done;
	}

	/*
	 * Copy the object's numeric value to the argument record,
	 * converting it if necessary. 
	 */

	if (valuePtr->typePtr == &tclIntType) {
	    i = valuePtr->internalRep.longValue;
	    if (mathFuncPtr->argTypes[k] == TCL_DOUBLE) {
		args[k].type = TCL_DOUBLE;
		args[k].doubleValue = i;
	    } else if (mathFuncPtr->argTypes[k] == TCL_WIDE_INT) {
		args[k].type = TCL_WIDE_INT;
		args[k].wideValue = Tcl_LongAsWide(i);
	    } else {
		args[k].type = TCL_INT;
		args[k].intValue = i;
	    }
	} else if (valuePtr->typePtr == &tclWideIntType) {
	    Tcl_WideInt w;
	    TclGetWide(w,valuePtr);
	    if (mathFuncPtr->argTypes[k] == TCL_DOUBLE) {
		args[k].type = TCL_DOUBLE;
		args[k].doubleValue = Tcl_WideAsDouble(w);
	    } else if (mathFuncPtr->argTypes[k] == TCL_INT) {
		args[k].type = TCL_INT;
		args[k].intValue = Tcl_WideAsLong(w);
	    } else {
		args[k].type = TCL_WIDE_INT;
		args[k].wideValue = w;
	    }
	} else {
	    d = valuePtr->internalRep.doubleValue;
	    if (mathFuncPtr->argTypes[k] == TCL_INT) {
		args[k].type = TCL_INT;
		args[k].intValue = (long) d;
	    } else if (mathFuncPtr->argTypes[k] == TCL_WIDE_INT) {
		args[k].type = TCL_WIDE_INT;
		args[k].wideValue = Tcl_DoubleAsWide(d);
	    } else {
		args[k].type = TCL_DOUBLE;
		args[k].doubleValue = d;
	    }
	}
    }

    /*
     * Invoke the function and copy its result back into valuePtr.
     */

    result = (*mathFuncPtr->proc)(mathFuncPtr->clientData, interp, args,
	    &funcResult);
    if (result != TCL_OK) {
	goto done;
    }

    /*
     * Pop the objc top stack elements and decrement their ref counts.
     */

    k = (stackTop - (objc-1));
    while (stackTop >= k) {
	valuePtr = POP_OBJECT();
	TclDecrRefCount(valuePtr);
    }
    
    /*
     * Push the call's object result.
     */
    
    if (funcResult.type == TCL_INT) {
	PUSH_OBJECT(Tcl_NewLongObj(funcResult.intValue));
    } else if (funcResult.type == TCL_WIDE_INT) {
	PUSH_OBJECT(Tcl_NewWideIntObj(funcResult.wideValue));
    } else {
	d = funcResult.doubleValue;
	if (IS_NAN(d) || IS_INF(d)) {
	    TclExprFloatError(interp, d);
	    result = TCL_ERROR;
	    goto done;
	}
	PUSH_OBJECT(Tcl_NewDoubleObj(d));
    }

    /*
     * Reflect the change to stackTop back in eePtr.
     */

    done:
    DECACHE_STACK_INFO();
    return result;
}

/*
 *----------------------------------------------------------------------
 *
 * TclExprFloatError --
 *
 *	This procedure is called when an error occurs during a
 *	floating-point operation. It reads errno and sets
 *	interp->objResultPtr accordingly.
 *
 * Results:
 *	interp->objResultPtr is set to hold an error message.
 *
 * Side effects:
 *	None.
 *
 *----------------------------------------------------------------------
 */

void
TclExprFloatError(interp, value)
    Tcl_Interp *interp;		/* Where to store error message. */
    double value;		/* Value returned after error;  used to
				 * distinguish underflows from overflows. */
{
    char *s;

    Tcl_ResetResult(interp);
    if ((errno == EDOM) || IS_NAN(value)) {
	s = "domain error: argument not in valid range";
	Tcl_AppendToObj(Tcl_GetObjResult(interp), s, -1);
	Tcl_SetErrorCode(interp, "ARITH", "DOMAIN", s, (char *) NULL);
    } else if ((errno == ERANGE) || IS_INF(value)) {
	if (value == 0.0) {
	    s = "floating-point value too small to represent";
	    Tcl_AppendToObj(Tcl_GetObjResult(interp), s, -1);
	    Tcl_SetErrorCode(interp, "ARITH", "UNDERFLOW", s, (char *) NULL);
	} else {
	    s = "floating-point value too large to represent";
	    Tcl_AppendToObj(Tcl_GetObjResult(interp), s, -1);
	    Tcl_SetErrorCode(interp, "ARITH", "OVERFLOW", s, (char *) NULL);
	}
    } else {
	char msg[64 + TCL_INTEGER_SPACE];
	
	sprintf(msg, "unknown floating-point error, errno = %d", errno);
	Tcl_AppendToObj(Tcl_GetObjResult(interp), msg, -1);
	Tcl_SetErrorCode(interp, "ARITH", "UNKNOWN", msg, (char *) NULL);
    }
}

#ifdef TCL_COMPILE_STATS
/*
 *----------------------------------------------------------------------
 *
 * TclLog2 --
 *
 *	Procedure used while collecting compilation statistics to determine
 *	the log base 2 of an integer.
 *
 * Results:
 *	Returns the log base 2 of the operand. If the argument is less
 *	than or equal to zero, a zero is returned.
 *
 * Side effects:
 *	None.
 *
 *----------------------------------------------------------------------
 */

int
TclLog2(value)
    register int value;		/* The integer for which to compute the
				 * log base 2. */
{
    register int n = value;
    register int result = 0;

    while (n > 1) {
	n = n >> 1;
	result++;
    }
    return result;
}

/*
 *----------------------------------------------------------------------
 *
 * EvalStatsCmd --
 *
 *	Implements the "evalstats" command that prints instruction execution
 *	counts to stdout.
 *
 * Results:
 *	Standard Tcl results.
 *
 * Side effects:
 *	None.
 *
 *----------------------------------------------------------------------
 */

static int
EvalStatsCmd(unused, interp, objc, objv)
    ClientData unused;		/* Unused. */
    Tcl_Interp *interp;		/* The current interpreter. */
    int objc;			/* The number of arguments. */
    Tcl_Obj *CONST objv[];	/* The argument strings. */
{
    Interp *iPtr = (Interp *) interp;
    LiteralTable *globalTablePtr = &(iPtr->literalTable);
    ByteCodeStats *statsPtr = &(iPtr->stats);
    double totalCodeBytes, currentCodeBytes;
    double totalLiteralBytes, currentLiteralBytes;
    double objBytesIfUnshared, strBytesIfUnshared, sharingBytesSaved;
    double strBytesSharedMultX, strBytesSharedOnce;
    double numInstructions, currentHeaderBytes;
    long numCurrentByteCodes, numByteCodeLits;
    long refCountSum, literalMgmtBytes, sum;
    int numSharedMultX, numSharedOnce;
    int decadeHigh, minSizeDecade, maxSizeDecade, length, i;
    char *litTableStats;
    LiteralEntry *entryPtr;

    numInstructions = 0.0;
    for (i = 0;  i < 256;  i++) {
        if (statsPtr->instructionCount[i] != 0) {
            numInstructions += statsPtr->instructionCount[i];
        }
    }

    totalLiteralBytes = sizeof(LiteralTable)
	    + iPtr->literalTable.numBuckets * sizeof(LiteralEntry *)
	    + (statsPtr->numLiteralsCreated * sizeof(LiteralEntry))
	    + (statsPtr->numLiteralsCreated * sizeof(Tcl_Obj))
	    + statsPtr->totalLitStringBytes;
    totalCodeBytes = statsPtr->totalByteCodeBytes + totalLiteralBytes;

    numCurrentByteCodes =
	    statsPtr->numCompilations - statsPtr->numByteCodesFreed;
    currentHeaderBytes = numCurrentByteCodes
	    * (sizeof(ByteCode) - (sizeof(size_t) + sizeof(Tcl_Time)));
    literalMgmtBytes = sizeof(LiteralTable)
	    + (iPtr->literalTable.numBuckets * sizeof(LiteralEntry *))
	    + (iPtr->literalTable.numEntries * sizeof(LiteralEntry));
    currentLiteralBytes = literalMgmtBytes
	    + iPtr->literalTable.numEntries * sizeof(Tcl_Obj)
	    + statsPtr->currentLitStringBytes;
    currentCodeBytes = statsPtr->currentByteCodeBytes + currentLiteralBytes;
    
    /*
     * Summary statistics, total and current source and ByteCode sizes.
     */

    fprintf(stdout, "\n----------------------------------------------------------------\n");
    fprintf(stdout,
	    "Compilation and execution statistics for interpreter 0x%x\n",
	    (unsigned int) iPtr);

    fprintf(stdout, "\nNumber ByteCodes executed	%ld\n",
	    statsPtr->numExecutions);
    fprintf(stdout, "Number ByteCodes compiled	%ld\n",
	    statsPtr->numCompilations);
    fprintf(stdout, "  Mean executions/compile	%.1f\n",
	    ((float)statsPtr->numExecutions) / ((float)statsPtr->numCompilations));
    
    fprintf(stdout, "\nInstructions executed		%.0f\n",
	    numInstructions);
    fprintf(stdout, "  Mean inst/compile		%.0f\n",
	    numInstructions / statsPtr->numCompilations);
    fprintf(stdout, "  Mean inst/execution		%.0f\n",
	    numInstructions / statsPtr->numExecutions);

    fprintf(stdout, "\nTotal ByteCodes			%ld\n",
	    statsPtr->numCompilations);
    fprintf(stdout, "  Source bytes			%.6g\n",
	    statsPtr->totalSrcBytes);
    fprintf(stdout, "  Code bytes			%.6g\n",
	    totalCodeBytes);
    fprintf(stdout, "    ByteCode bytes		%.6g\n",
	    statsPtr->totalByteCodeBytes);
    fprintf(stdout, "    Literal bytes		%.6g\n",
	    totalLiteralBytes);
    fprintf(stdout, "      table %d + bkts %d + entries %ld + objects %ld + strings %.6g\n",
	    sizeof(LiteralTable),
	    iPtr->literalTable.numBuckets * sizeof(LiteralEntry *),
	    statsPtr->numLiteralsCreated * sizeof(LiteralEntry),
	    statsPtr->numLiteralsCreated * sizeof(Tcl_Obj),
	    statsPtr->totalLitStringBytes);
    fprintf(stdout, "  Mean code/compile		%.1f\n",
	    totalCodeBytes / statsPtr->numCompilations);
    fprintf(stdout, "  Mean code/source		%.1f\n",
	    totalCodeBytes / statsPtr->totalSrcBytes);

    fprintf(stdout, "\nCurrent (active) ByteCodes	%ld\n",
	    numCurrentByteCodes);
    fprintf(stdout, "  Source bytes			%.6g\n",
	    statsPtr->currentSrcBytes);
    fprintf(stdout, "  Code bytes			%.6g\n",
	    currentCodeBytes);
    fprintf(stdout, "    ByteCode bytes		%.6g\n",
	    statsPtr->currentByteCodeBytes);
    fprintf(stdout, "    Literal bytes		%.6g\n",
	    currentLiteralBytes);
    fprintf(stdout, "      table %d + bkts %d + entries %d + objects %d + strings %.6g\n",
	    sizeof(LiteralTable),
	    iPtr->literalTable.numBuckets * sizeof(LiteralEntry *),
	    iPtr->literalTable.numEntries * sizeof(LiteralEntry),
	    iPtr->literalTable.numEntries * sizeof(Tcl_Obj),
	    statsPtr->currentLitStringBytes);
    fprintf(stdout, "  Mean code/source		%.1f\n",
	    currentCodeBytes / statsPtr->currentSrcBytes);
    fprintf(stdout, "  Code + source bytes		%.6g (%0.1f mean code/src)\n",
	    (currentCodeBytes + statsPtr->currentSrcBytes),
	    (currentCodeBytes / statsPtr->currentSrcBytes) + 1.0);

    /*
     * Tcl_IsShared statistics check
     *
     * This gives the refcount of each obj as Tcl_IsShared was called
     * for it.  Shared objects must be duplicated before they can be
     * modified.
     */

    numSharedMultX = 0;
    fprintf(stdout, "\nTcl_IsShared object check (all objects):\n");
    fprintf(stdout, "  Object had refcount <=1 (not shared)	%ld\n",
	    tclObjsShared[1]);
    for (i = 2;  i < TCL_MAX_SHARED_OBJ_STATS;  i++) {
	fprintf(stdout, "  refcount ==%d		%ld\n",
		i, tclObjsShared[i]);
	numSharedMultX += tclObjsShared[i];
    }
    fprintf(stdout, "  refcount >=%d		%ld\n",
	    i, tclObjsShared[0]);
    numSharedMultX += tclObjsShared[0];
    fprintf(stdout, "  Total shared objects			%d\n",
	    numSharedMultX);

    /*
     * Literal table statistics.
     */

    numByteCodeLits = 0;
    refCountSum = 0;
    numSharedMultX = 0;
    numSharedOnce  = 0;
    objBytesIfUnshared  = 0.0;
    strBytesIfUnshared  = 0.0;
    strBytesSharedMultX = 0.0;
    strBytesSharedOnce  = 0.0;
    for (i = 0;  i < globalTablePtr->numBuckets;  i++) {
	for (entryPtr = globalTablePtr->buckets[i];  entryPtr != NULL;
	        entryPtr = entryPtr->nextPtr) {
	    if (entryPtr->objPtr->typePtr == &tclByteCodeType) {
		numByteCodeLits++;
	    }
	    (void) Tcl_GetStringFromObj(entryPtr->objPtr, &length);
	    refCountSum += entryPtr->refCount;
	    objBytesIfUnshared += (entryPtr->refCount * sizeof(Tcl_Obj));
	    strBytesIfUnshared += (entryPtr->refCount * (length+1));
	    if (entryPtr->refCount > 1) {
		numSharedMultX++;
		strBytesSharedMultX += (length+1);
	    } else {
		numSharedOnce++;
		strBytesSharedOnce += (length+1);
	    }
	}
    }
    sharingBytesSaved = (objBytesIfUnshared + strBytesIfUnshared)
	    - currentLiteralBytes;

    fprintf(stdout, "\nTotal objects (all interps)	%ld\n",
	    tclObjsAlloced);
    fprintf(stdout, "Current objects			%ld\n",
	    (tclObjsAlloced - tclObjsFreed));
    fprintf(stdout, "Total literal objects		%ld\n",
	    statsPtr->numLiteralsCreated);

    fprintf(stdout, "\nCurrent literal objects		%d (%0.1f%% of current objects)\n",
	    globalTablePtr->numEntries,
	    (globalTablePtr->numEntries * 100.0) / (tclObjsAlloced-tclObjsFreed));
    fprintf(stdout, "  ByteCode literals	 	%ld (%0.1f%% of current literals)\n",
	    numByteCodeLits,
	    (numByteCodeLits * 100.0) / globalTablePtr->numEntries);
    fprintf(stdout, "  Literals reused > 1x	 	%d\n",
	    numSharedMultX);
    fprintf(stdout, "  Mean reference count	 	%.2f\n",
	    ((double) refCountSum) / globalTablePtr->numEntries);
    fprintf(stdout, "  Mean len, str reused >1x 	%.2f\n",
	    (numSharedMultX? (strBytesSharedMultX/numSharedMultX) : 0.0));
    fprintf(stdout, "  Mean len, str used 1x	 	%.2f\n",
	    (numSharedOnce? (strBytesSharedOnce/numSharedOnce) : 0.0));
    fprintf(stdout, "  Total sharing savings	 	%.6g (%0.1f%% of bytes if no sharing)\n",
	    sharingBytesSaved,
	    (sharingBytesSaved * 100.0) / (objBytesIfUnshared + strBytesIfUnshared));
    fprintf(stdout, "    Bytes with sharing		%.6g\n",
	    currentLiteralBytes);
    fprintf(stdout, "      table %d + bkts %d + entries %d + objects %d + strings %.6g\n",
	    sizeof(LiteralTable),
	    iPtr->literalTable.numBuckets * sizeof(LiteralEntry *),
	    iPtr->literalTable.numEntries * sizeof(LiteralEntry),
	    iPtr->literalTable.numEntries * sizeof(Tcl_Obj),
	    statsPtr->currentLitStringBytes);
    fprintf(stdout, "    Bytes if no sharing		%.6g = objects %.6g + strings %.6g\n",
	    (objBytesIfUnshared + strBytesIfUnshared),
	    objBytesIfUnshared, strBytesIfUnshared);
    fprintf(stdout, "  String sharing savings 	%.6g = unshared %.6g - shared %.6g\n",
	    (strBytesIfUnshared - statsPtr->currentLitStringBytes),
	    strBytesIfUnshared, statsPtr->currentLitStringBytes);
    fprintf(stdout, "  Literal mgmt overhead	 	%ld (%0.1f%% of bytes with sharing)\n",
	    literalMgmtBytes,
	    (literalMgmtBytes * 100.0) / currentLiteralBytes);
    fprintf(stdout, "    table %d + buckets %d + entries %d\n",
	    sizeof(LiteralTable),
	    iPtr->literalTable.numBuckets * sizeof(LiteralEntry *),
	    iPtr->literalTable.numEntries * sizeof(LiteralEntry));

    /*
     * Breakdown of current ByteCode space requirements.
     */
    
    fprintf(stdout, "\nBreakdown of current ByteCode requirements:\n");
    fprintf(stdout, "                         Bytes      Pct of    Avg per\n");
    fprintf(stdout, "                                     total    ByteCode\n");
    fprintf(stdout, "Total             %12.6g     100.00%%   %8.1f\n",
	    statsPtr->currentByteCodeBytes,
	    statsPtr->currentByteCodeBytes / numCurrentByteCodes);
    fprintf(stdout, "Header            %12.6g   %8.1f%%   %8.1f\n",
	    currentHeaderBytes,
	    ((currentHeaderBytes * 100.0) / statsPtr->currentByteCodeBytes),
	    currentHeaderBytes / numCurrentByteCodes);
    fprintf(stdout, "Instructions      %12.6g   %8.1f%%   %8.1f\n",
	    statsPtr->currentInstBytes,
	    ((statsPtr->currentInstBytes * 100.0) / statsPtr->currentByteCodeBytes),
	    statsPtr->currentInstBytes / numCurrentByteCodes);
    fprintf(stdout, "Literal ptr array %12.6g   %8.1f%%   %8.1f\n",
	    statsPtr->currentLitBytes,
	    ((statsPtr->currentLitBytes * 100.0) / statsPtr->currentByteCodeBytes),
	    statsPtr->currentLitBytes / numCurrentByteCodes);
    fprintf(stdout, "Exception table   %12.6g   %8.1f%%   %8.1f\n",
	    statsPtr->currentExceptBytes,
	    ((statsPtr->currentExceptBytes * 100.0) / statsPtr->currentByteCodeBytes),
	    statsPtr->currentExceptBytes / numCurrentByteCodes);
    fprintf(stdout, "Auxiliary data    %12.6g   %8.1f%%   %8.1f\n",
	    statsPtr->currentAuxBytes,
	    ((statsPtr->currentAuxBytes * 100.0) / statsPtr->currentByteCodeBytes),
	    statsPtr->currentAuxBytes / numCurrentByteCodes);
    fprintf(stdout, "Command map       %12.6g   %8.1f%%   %8.1f\n",
	    statsPtr->currentCmdMapBytes,
	    ((statsPtr->currentCmdMapBytes * 100.0) / statsPtr->currentByteCodeBytes),
	    statsPtr->currentCmdMapBytes / numCurrentByteCodes);

    /*
     * Detailed literal statistics.
     */
    
    fprintf(stdout, "\nLiteral string sizes:\n");
    fprintf(stdout, "	 Up to length		Percentage\n");
    maxSizeDecade = 0;
    for (i = 31;  i >= 0;  i--) {
        if (statsPtr->literalCount[i] > 0) {
            maxSizeDecade = i;
	    break;
        }
    }
    sum = 0;
    for (i = 0;  i <= maxSizeDecade;  i++) {
	decadeHigh = (1 << (i+1)) - 1;
	sum += statsPtr->literalCount[i];
        fprintf(stdout,	"	%10d		%8.0f%%\n",
		decadeHigh, (sum * 100.0) / statsPtr->numLiteralsCreated);
    }

    litTableStats = TclLiteralStats(globalTablePtr);
    fprintf(stdout, "\nCurrent literal table statistics:\n%s\n",
            litTableStats);
    ckfree((char *) litTableStats);

    /*
     * Source and ByteCode size distributions.
     */

    fprintf(stdout, "\nSource sizes:\n");
    fprintf(stdout, "	 Up to size		Percentage\n");
    minSizeDecade = maxSizeDecade = 0;
    for (i = 0;  i < 31;  i++) {
        if (statsPtr->srcCount[i] > 0) {
	    minSizeDecade = i;
	    break;
        }
    }
    for (i = 31;  i >= 0;  i--) {
        if (statsPtr->srcCount[i] > 0) {
            maxSizeDecade = i;
	    break;
        }
    }
    sum = 0;
    for (i = minSizeDecade;  i <= maxSizeDecade;  i++) {
	decadeHigh = (1 << (i+1)) - 1;
	sum += statsPtr->srcCount[i];
        fprintf(stdout,	"	%10d		%8.0f%%\n",
		decadeHigh, (sum * 100.0) / statsPtr->numCompilations);
    }

    fprintf(stdout, "\nByteCode sizes:\n");
    fprintf(stdout, "	 Up to size		Percentage\n");
    minSizeDecade = maxSizeDecade = 0;
    for (i = 0;  i < 31;  i++) {
        if (statsPtr->byteCodeCount[i] > 0) {
	    minSizeDecade = i;
	    break;
        }
    }
    for (i = 31;  i >= 0;  i--) {
        if (statsPtr->byteCodeCount[i] > 0) {
            maxSizeDecade = i;
	    break;
        }
    }
    sum = 0;
    for (i = minSizeDecade;  i <= maxSizeDecade;  i++) {
	decadeHigh = (1 << (i+1)) - 1;
	sum += statsPtr->byteCodeCount[i];
        fprintf(stdout,	"	%10d		%8.0f%%\n",
		decadeHigh, (sum * 100.0) / statsPtr->numCompilations);
    }

    fprintf(stdout, "\nByteCode longevity (excludes Current ByteCodes):\n");
    fprintf(stdout, "	       Up to ms		Percentage\n");
    minSizeDecade = maxSizeDecade = 0;
    for (i = 0;  i < 31;  i++) {
        if (statsPtr->lifetimeCount[i] > 0) {
	    minSizeDecade = i;
	    break;
        }
    }
    for (i = 31;  i >= 0;  i--) {
        if (statsPtr->lifetimeCount[i] > 0) {
            maxSizeDecade = i;
	    break;
        }
    }
    sum = 0;
    for (i = minSizeDecade;  i <= maxSizeDecade;  i++) {
	decadeHigh = (1 << (i+1)) - 1;
	sum += statsPtr->lifetimeCount[i];
        fprintf(stdout,	"	%12.3f		%8.0f%%\n",
		decadeHigh / 1000.0,
		(sum * 100.0) / statsPtr->numByteCodesFreed);
    }

    /*
     * Instruction counts.
     */

    fprintf(stdout, "\nInstruction counts:\n");
    for (i = 0;  i <= LAST_INST_OPCODE;  i++) {
        if (statsPtr->instructionCount[i]) {
            fprintf(stdout, "%20s %8ld %6.1f%%\n",
		    tclInstructionTable[i].name,
		    statsPtr->instructionCount[i],
		    (statsPtr->instructionCount[i]*100.0) / numInstructions);
        }
    }

    fprintf(stdout, "\nInstructions NEVER executed:\n");
    for (i = 0;  i <= LAST_INST_OPCODE;  i++) {
        if (statsPtr->instructionCount[i] == 0) {
            fprintf(stdout, "%20s\n", tclInstructionTable[i].name);
        }
    }

#ifdef TCL_MEM_DEBUG
    fprintf(stdout, "\nHeap Statistics:\n");
    TclDumpMemoryInfo(stdout);
#endif
    fprintf(stdout, "\n----------------------------------------------------------------\n");
    return TCL_OK;
}
#endif /* TCL_COMPILE_STATS */

#ifdef TCL_COMPILE_DEBUG
/*
 *----------------------------------------------------------------------
 *
 * StringForResultCode --
 *
 *	Procedure that returns a human-readable string representing a
 *	Tcl result code such as TCL_ERROR. 
 *
 * Results:
 *	If the result code is one of the standard Tcl return codes, the
 *	result is a string representing that code such as "TCL_ERROR".
 *	Otherwise, the result string is that code formatted as a
 *	sequence of decimal digit characters. Note that the resulting
 *	string must not be modified by the caller.
 *
 * Side effects:
 *	None.
 *
 *----------------------------------------------------------------------
 */

static char *
StringForResultCode(result)
    int result;			/* The Tcl result code for which to
				 * generate a string. */
{
    static char buf[TCL_INTEGER_SPACE];
    
    if ((result >= TCL_OK) && (result <= TCL_CONTINUE)) {
	return resultStrings[result];
    }
    TclFormatInt(buf, result);
    return buf;
}
#endif /* TCL_COMPILE_DEBUG */