ran dos2unix on this file--Irix couldn't build Tcl because it detected strange

chars at the end of each line.

1 files changed, 1062 insertions, 1062 deletions

diff --git a/generic/tclLiteral.c b/generic/tclLiteral.c
index 99e46ae..37c9be9 100644
--- a/generic/tclLiteral.c
+++ b/generic/tclLiteral.c
@@ -1,1062 +1,1062 @@
-/* 

- * tclLiteral.c --

- *

- *	Implementation of the global and ByteCode-local literal tables

- *	used to manage the Tcl objects created for literal values during

- *	compilation of Tcl scripts. This implementation borrows heavily

- *	from the more general hashtable implementation of Tcl hash tables

- *	that appears in tclHash.c.

- *

- * Copyright (c) 1997-1998 Sun Microsystems, Inc.

- *

- * See the file "license.terms" for information on usage and redistribution

- * of this file, and for a DISCLAIMER OF ALL WARRANTIES.

- *

- * RCS: @(#) $Id: tclLiteral.c,v 1.5 1999/05/05 00:35:41 surles Exp $

- */

-

-#include "tclInt.h"

-#include "tclCompile.h"

-#include "tclPort.h"

-/*

- * When there are this many entries per bucket, on average, rebuild

- * a literal's hash table to make it larger.

- */

-

-#define REBUILD_MULTIPLIER	3

-

-/*

- * Procedure prototypes for static procedures in this file:

- */

-

-static int		AddLocalLiteralEntry _ANSI_ARGS_((

-			    CompileEnv *envPtr, LiteralEntry *globalPtr,

-			    int localHash));

-static void		ExpandLocalLiteralArray _ANSI_ARGS_((

-			    CompileEnv *envPtr));

-static unsigned int	HashString _ANSI_ARGS_((CONST char *bytes,

-			    int length));

-static void		RebuildLiteralTable _ANSI_ARGS_((

-			    LiteralTable *tablePtr));

-

-/*

- *----------------------------------------------------------------------

- *

- * TclInitLiteralTable --

- *

- *	This procedure is called to initialize the fields of a literal table

- *	structure for either an interpreter or a compilation's CompileEnv

- *	structure.

- *

- * Results:

- *	None.

- *

- * Side effects: 

- *	The literal table is made ready for use.

- *

- *----------------------------------------------------------------------

- */

-

-void

-TclInitLiteralTable(tablePtr)

-    register LiteralTable *tablePtr; /* Pointer to table structure, which

-				      * is supplied by the caller. */

-{

-#if (TCL_SMALL_HASH_TABLE != 4) 

-    panic("TclInitLiteralTable: TCL_SMALL_HASH_TABLE is %d, not 4\n",

-	    TCL_SMALL_HASH_TABLE);

-#endif

-    

-    tablePtr->buckets = tablePtr->staticBuckets;

-    tablePtr->staticBuckets[0] = tablePtr->staticBuckets[1] = 0;

-    tablePtr->staticBuckets[2] = tablePtr->staticBuckets[3] = 0;

-    tablePtr->numBuckets = TCL_SMALL_HASH_TABLE;

-    tablePtr->numEntries = 0;

-    tablePtr->rebuildSize = TCL_SMALL_HASH_TABLE*REBUILD_MULTIPLIER;

-    tablePtr->mask = 3;

-}

-

-/*

- *----------------------------------------------------------------------

- *

- * TclDeleteLiteralTable --

- *

- *	This procedure frees up everything associated with a literal table

- *	except for the table's structure itself.

- *

- * Results:

- *	None.

- *

- * Side effects:

- *	Each literal in the table is released: i.e., its reference count

- *	in the global literal table is decremented and, if it becomes zero,

- *	the literal is freed. In addition, the table's bucket array is

- *	freed.

- *

- *----------------------------------------------------------------------

- */

-

-void

-TclDeleteLiteralTable(interp, tablePtr)

-    Tcl_Interp *interp;		/* Interpreter containing shared literals

-				 * referenced by the table to delete. */

-    LiteralTable *tablePtr;	/* Points to the literal table to delete. */

-{

-    LiteralEntry *entryPtr;

-    int i, start;

-

-    /*

-     * Release remaining literals in the table. Note that releasing a

-     * literal might release other literals, modifying the table, so we

-     * restart the search from the bucket chain we last found an entry.

-     */

-

-#ifdef TCL_COMPILE_DEBUG

-    TclVerifyGlobalLiteralTable((Interp *) interp);

-#endif /*TCL_COMPILE_DEBUG*/

-

-    start = 0;

-    while (tablePtr->numEntries > 0) {

-	for (i = start;  i < tablePtr->numBuckets;  i++) {

-	    entryPtr = tablePtr->buckets[i];

-	    if (entryPtr != NULL) {

-		TclReleaseLiteral(interp, entryPtr->objPtr);

-		start = i;

-		break;

-	    }

-	}

-    }

-

-    /*

-     * Free up the table's bucket array if it was dynamically allocated.

-     */

-

-    if (tablePtr->buckets != tablePtr->staticBuckets) {

-	ckfree((char *) tablePtr->buckets);

-    }

-}

-

-/*

- *----------------------------------------------------------------------

- *

- * TclRegisterLiteral --

- *

- *	Find, or if necessary create, an object in a CompileEnv literal

- *	array that has a string representation matching the argument string.

- *

- * Results:

- *	The index in the CompileEnv's literal array that references a

- *	shared literal matching the string. The object is created if

- *	necessary.

- *

- * Side effects:

- *	To maximize sharing, we look up the string in the interpreter's

- *	global literal table. If not found, we create a new shared literal

- *	in the global table. We then add a reference to the shared

- *	literal in the CompileEnv's literal array. 

- *

- *	If onHeap is 1, this procedure is given ownership of the string: if

- *	an object is created then its string representation is set directly

- *	from string, otherwise the string is freed. Typically, a caller sets

- *	onHeap 1 if "string" is an already heap-allocated buffer holding the

- *	result of backslash substitutions.

- *

- *----------------------------------------------------------------------

- */

-

-int

-TclRegisterLiteral(envPtr, bytes, length, onHeap)

-    CompileEnv *envPtr;		/* Points to the CompileEnv in whose object

-				 * array an object is found or created. */

-    register char *bytes;	/* Points to string for which to find or

-				 * create an object in CompileEnv's object

-				 * array. */

-    int length;			/* Number of bytes in the string. If < 0,

-				 * the string consists of all bytes up to

-				 * the first null character. */

-    int onHeap;			/* If 1 then the caller already malloc'd

-				 * bytes and ownership is passed to this

-				 * procedure. */

-{

-    Interp *iPtr = envPtr->iPtr;

-    LiteralTable *globalTablePtr = &(iPtr->literalTable);

-    LiteralTable *localTablePtr = &(envPtr->localLitTable);

-    register LiteralEntry *globalPtr, *localPtr;

-    register Tcl_Obj *objPtr;

-    unsigned int hash;

-    int localHash, globalHash, objIndex;

-    long n;

-    char buf[TCL_INTEGER_SPACE];

-

- 

-    if (length < 0) {

-	length = (bytes? strlen(bytes) : 0);

-    }

-    hash = HashString(bytes, length);

-

-    /*

-     * Is the literal already in the CompileEnv's local literal array?

-     * If so, just return its index.

-     */

-

-    localHash = (hash & localTablePtr->mask);

-    for (localPtr = localTablePtr->buckets[localHash];

-	  localPtr != NULL;  localPtr = localPtr->nextPtr) {

-	objPtr = localPtr->objPtr;

-	if ((objPtr->length == length) && ((length == 0)

-		|| ((objPtr->bytes[0] == bytes[0])

-			&& (memcmp(objPtr->bytes, bytes, (unsigned) length)

-				== 0)))) {

-	    if (onHeap) {

-		ckfree(bytes);

-	    }

-	    objIndex = (localPtr - envPtr->literalArrayPtr);

-#ifdef TCL_COMPILE_DEBUG

-	    TclVerifyLocalLiteralTable(envPtr);

-#endif /*TCL_COMPILE_DEBUG*/

-

-	    return objIndex;

-	}

-    }

-

-    /*

-     * The literal is new to this CompileEnv. Is it in the interpreter's

-     * global literal table?

-     */

-

-    globalHash = (hash & globalTablePtr->mask);

-    for (globalPtr = globalTablePtr->buckets[globalHash];

-	 globalPtr != NULL;  globalPtr = globalPtr->nextPtr) {

-	objPtr = globalPtr->objPtr;

-	if ((objPtr->length == length) && ((length == 0)

-		|| ((objPtr->bytes[0] == bytes[0])

-			&& (memcmp(objPtr->bytes, bytes, (unsigned) length)

-				== 0)))) {

-	    /*

-	     * A global literal was found. Add an entry to the CompileEnv's

-	     * local literal array.

-	     */

-	    

-	    if (onHeap) {

-		ckfree(bytes);

-	    }

-	    objIndex = AddLocalLiteralEntry(envPtr, globalPtr, localHash);

-#ifdef TCL_COMPILE_DEBUG

-	    if (globalPtr->refCount < 1) {

-		panic("TclRegisterLiteral: global literal \"%.*s\" had bad refCount %d",

-			(length>60? 60 : length), bytes,

-			globalPtr->refCount);

-	    }

-	    TclVerifyLocalLiteralTable(envPtr);

-#endif /*TCL_COMPILE_DEBUG*/ 

-	    return objIndex;

-	}

-    }

-

-    /*

-     * The literal is new to the interpreter. Add it to the global literal

-     * table then add an entry to the CompileEnv's local literal array.

-     * Convert the object to an integer object if possible.

-     */

-

-    TclNewObj(objPtr);

-    Tcl_IncrRefCount(objPtr);

-    if (onHeap) {

-	objPtr->bytes = bytes;

-	objPtr->length = length;

-    } else {

-	TclInitStringRep(objPtr, bytes, length);

-    }

-

-    if (TclLooksLikeInt(bytes, length)) {

-	if (TclGetLong((Tcl_Interp *) NULL, bytes, &n) == TCL_OK) {

-	    TclFormatInt(buf, n);

-	    if (strcmp(bytes, buf) == 0) {

-		objPtr->internalRep.longValue = n;

-		objPtr->typePtr = &tclIntType;

-	    }

-	}

-    }

-    

-#ifdef TCL_COMPILE_DEBUG

-    if (TclLookupLiteralEntry((Tcl_Interp *) iPtr, objPtr) != NULL) {

-	panic("TclRegisterLiteral: literal \"%.*s\" found globally but shouldn't be",

-	        (length>60? 60 : length), bytes);

-    }

-#endif

-

-    globalPtr = (LiteralEntry *) ckalloc((unsigned) sizeof(LiteralEntry));

-    globalPtr->objPtr = objPtr;

-    globalPtr->refCount = 0;

-    globalPtr->nextPtr = globalTablePtr->buckets[globalHash];

-    globalTablePtr->buckets[globalHash] = globalPtr;

-    globalTablePtr->numEntries++;

-

-    /*

-     * If the global literal table has exceeded a decent size, rebuild it

-     * with more buckets.

-     */

-

-    if (globalTablePtr->numEntries >= globalTablePtr->rebuildSize) {

-	RebuildLiteralTable(globalTablePtr);

-    }

-    

-    objIndex = AddLocalLiteralEntry(envPtr, globalPtr, localHash);

-

-#ifdef TCL_COMPILE_DEBUG

-    TclVerifyGlobalLiteralTable(iPtr);

-    TclVerifyLocalLiteralTable(envPtr);

-    {

-	LiteralEntry *entryPtr;

-	int found, i;

-	found = 0;

-	for (i = 0;  i < globalTablePtr->numBuckets;  i++) {

-	    for (entryPtr = globalTablePtr->buckets[i];

-		    entryPtr != NULL;  entryPtr = entryPtr->nextPtr) {

-		if ((entryPtr == globalPtr)

-		        && (entryPtr->objPtr == objPtr)) {

-		    found = 1;

-		}

-	    }

-	}

-	if (!found) {

-	    panic("TclRegisterLiteral: literal \"%.*s\" wasn't global",

-	            (length>60? 60 : length), bytes);

-	}

-    }

-#endif /*TCL_COMPILE_DEBUG*/

-#ifdef TCL_COMPILE_STATS   

-    iPtr->stats.numLiteralsCreated++;

-    iPtr->stats.totalLitStringBytes   += (double) (length + 1);

-    iPtr->stats.currentLitStringBytes += (double) (length + 1);

-    iPtr->stats.literalCount[TclLog2(length)]++;

-#endif /*TCL_COMPILE_STATS*/

-    return objIndex;

-}

-

-/*

- *----------------------------------------------------------------------

- *

- * TclLookupLiteralEntry --

- *

- *	Finds the LiteralEntry that corresponds to a literal Tcl object

- *      holding a literal.

- *

- * Results:

- *      Returns the matching LiteralEntry if found, otherwise NULL.

- *

- * Side effects:

- *      None.

- *

- *----------------------------------------------------------------------

- */

-

-LiteralEntry *

-TclLookupLiteralEntry(interp, objPtr)

-    Tcl_Interp *interp;		/* Interpreter for which objPtr was created

-                                 * to hold a literal. */

-    register Tcl_Obj *objPtr;	/* Points to a Tcl object holding a

-                                 * literal that was previously created by a

-                                 * call to TclRegisterLiteral. */

-{

-    Interp *iPtr = (Interp *) interp;

-    LiteralTable *globalTablePtr = &(iPtr->literalTable);

-    register LiteralEntry *entryPtr;

-    char *bytes;

-    int length, globalHash;

-

-    bytes = Tcl_GetStringFromObj(objPtr, &length);

-    globalHash = (HashString(bytes, length) & globalTablePtr->mask);

-    for (entryPtr = globalTablePtr->buckets[globalHash];

-            entryPtr != NULL;  entryPtr = entryPtr->nextPtr) {

-        if (entryPtr->objPtr == objPtr) {

-            return entryPtr;

-        }

-    }

-    return NULL;

-}

-

-/*

- *----------------------------------------------------------------------

- *

- * TclHideLiteral --

- *

- *	Remove a literal entry from the literal hash tables, leaving it in

- *	the literal array so existing references continue to function.

- *	This makes it possible to turn a shared literal into a private

- *	literal that cannot be shared.

- *

- * Results:

- *	None.

- *

- * Side effects:

- *	Removes the literal from the local hash table and decrements the

- *	global hash entry's reference count.

- *

- *----------------------------------------------------------------------

- */

-

-void

-TclHideLiteral(interp, envPtr, index)

-    Tcl_Interp *interp;		 /* Interpreter for which objPtr was created

-                                  * to hold a literal. */

-    register CompileEnv *envPtr; /* Points to CompileEnv whose literal array

-				  * contains the entry being hidden. */

-    int index;			 /* The index of the entry in the literal

-				  * array. */

-{

-    LiteralEntry **nextPtrPtr, *entryPtr, *lPtr;

-    LiteralTable *localTablePtr = &(envPtr->localLitTable);

-    int localHash, length;

-    char *bytes;

-    Tcl_Obj *newObjPtr;

-

-    lPtr = &(envPtr->literalArrayPtr[index]);

-

-    /*

-     * To avoid unwanted sharing we need to copy the object and remove it from

-     * the local and global literal tables.  It still has a slot in the literal

-     * array so it can be referred to by byte codes, but it will not be matched

-     * by literal searches.

-     */

-

-    newObjPtr = Tcl_DuplicateObj(lPtr->objPtr);

-    Tcl_IncrRefCount(newObjPtr);

-    TclReleaseLiteral(interp, lPtr->objPtr);

-    lPtr->objPtr = newObjPtr;

-

-    bytes = Tcl_GetStringFromObj(newObjPtr, &length);

-    localHash = (HashString(bytes, length) & localTablePtr->mask);

-    nextPtrPtr = &localTablePtr->buckets[localHash];

-

-    for (entryPtr = *nextPtrPtr; entryPtr != NULL; entryPtr = *nextPtrPtr) {

-	if (entryPtr == lPtr) {

-	    *nextPtrPtr = lPtr->nextPtr;

-	    lPtr->nextPtr = NULL;

-	    localTablePtr->numEntries--;

-	    break;

-	}

-	nextPtrPtr = &entryPtr->nextPtr;

-    }

-}

-

-/*

- *----------------------------------------------------------------------

- *

- * TclAddLiteralObj --

- *

- *	Add a single literal object to the literal array.  This

- *	function does not add the literal to the local or global

- *	literal tables.  The caller is expected to add the entry

- *	to whatever tables are appropriate.

- *

- * Results:

- *	The index in the CompileEnv's literal array that references the

- *	literal.  Stores the pointer to the new literal entry in the

- *	location referenced by the localPtrPtr argument.

- *

- * Side effects:

- *	Expands the literal array if necessary.  Increments the refcount

- *	on the literal object.

- *

- *----------------------------------------------------------------------

- */

-

-int

-TclAddLiteralObj(envPtr, objPtr, litPtrPtr)

-    register CompileEnv *envPtr; /* Points to CompileEnv in whose literal

-				  * array the object is to be inserted. */

-    Tcl_Obj *objPtr;		 /* The object to insert into the array. */

-    LiteralEntry **litPtrPtr;	 /* The location where the pointer to the

-				  * new literal entry should be stored.

-				  * May be NULL. */

-{

-    register LiteralEntry *lPtr;

-    int objIndex;

-

-    if (envPtr->literalArrayNext >= envPtr->literalArrayEnd) {

-	ExpandLocalLiteralArray(envPtr);

-    }

-    objIndex = envPtr->literalArrayNext;

-    envPtr->literalArrayNext++;

-

-    lPtr = &(envPtr->literalArrayPtr[objIndex]);

-    lPtr->objPtr = objPtr;

-    Tcl_IncrRefCount(objPtr);

-    lPtr->refCount = -1;	/* i.e., unused */

-    lPtr->nextPtr = NULL;

-

-    if (litPtrPtr) {

-	*litPtrPtr = lPtr;

-    }

-

-    return objIndex;

-}

-

-/*

- *----------------------------------------------------------------------

- *

- * AddLocalLiteralEntry --

- *

- *	Insert a new literal into a CompileEnv's local literal array.

- *

- * Results:

- *	The index in the CompileEnv's literal array that references the

- *	literal.

- *

- * Side effects:

- *	Increments the ref count of the global LiteralEntry since the

- *	CompileEnv now refers to the literal. Expands the literal array

- *	if necessary. May rebuild the hash bucket array of the CompileEnv's

- *	literal array if it becomes too large.

- *

- *----------------------------------------------------------------------

- */

-

-static int

-AddLocalLiteralEntry(envPtr, globalPtr, localHash)

-    register CompileEnv *envPtr; /* Points to CompileEnv in whose literal

-				  * array the object is to be inserted. */

-    LiteralEntry *globalPtr;	 /* Points to the global LiteralEntry for

-				  * the literal to add to the CompileEnv. */

-    int localHash;		 /* Hash value for the literal's string. */

-{

-    register LiteralTable *localTablePtr = &(envPtr->localLitTable);

-    LiteralEntry *localPtr;

-    int objIndex;

-    

-    objIndex = TclAddLiteralObj(envPtr, globalPtr->objPtr, &localPtr);

-

-    /*

-     * Add the literal to the local table.

-     */

-

-    localPtr->nextPtr = localTablePtr->buckets[localHash];

-    localTablePtr->buckets[localHash] = localPtr;

-    localTablePtr->numEntries++;

-

-    globalPtr->refCount++;

-

-    /*

-     * If the CompileEnv's local literal table has exceeded a decent size,

-     * rebuild it with more buckets.

-     */

-

-    if (localTablePtr->numEntries >= localTablePtr->rebuildSize) {

-	RebuildLiteralTable(localTablePtr);

-    }

-

-#ifdef TCL_COMPILE_DEBUG

-    TclVerifyLocalLiteralTable(envPtr);

-    {

-	char *bytes;

-	int length, found, i;

-	found = 0;

-	for (i = 0;  i < localTablePtr->numBuckets;  i++) {

-	    for (localPtr = localTablePtr->buckets[i];

-		    localPtr != NULL;  localPtr = localPtr->nextPtr) {

-		if (localPtr->objPtr == globalPtr->objPtr) {

-		    found = 1;

-		}

-	    }

-	}

-	if (!found) {

-	    bytes = Tcl_GetStringFromObj(globalPtr->objPtr, &length);

-	    panic("AddLocalLiteralEntry: literal \"%.*s\" wasn't found locally",

-	            (length>60? 60 : length), bytes);

-	}

-    }

-#endif /*TCL_COMPILE_DEBUG*/

-    return objIndex;

-}

-

-/*

- *----------------------------------------------------------------------

- *

- * ExpandLocalLiteralArray --

- *

- *	Procedure that uses malloc to allocate more storage for a

- *	CompileEnv's local literal array.

- *

- * Results:

- *	None.

- *

- * Side effects:

- *	The literal array in *envPtr is reallocated to a new array of

- *	double the size, and if envPtr->mallocedLiteralArray is non-zero

- *	the old array is freed. Entries are copied from the old array

- *	to the new one. The local literal table is updated to refer to

- *	the new entries.

- *

- *----------------------------------------------------------------------

- */

-

-static void

-ExpandLocalLiteralArray(envPtr)

-    register CompileEnv *envPtr; /* Points to the CompileEnv whose object

-				  * array must be enlarged. */

-{

-    /*

-     * The current allocated local literal entries are stored between

-     * elements 0 and (envPtr->literalArrayNext - 1) [inclusive].

-     */

-

-    LiteralTable *localTablePtr = &(envPtr->localLitTable);

-    int currElems = envPtr->literalArrayNext;

-    size_t currBytes = (currElems * sizeof(LiteralEntry));

-    register LiteralEntry *currArrayPtr = envPtr->literalArrayPtr;

-    register LiteralEntry *newArrayPtr =

-	    (LiteralEntry *) ckalloc((unsigned) (2 * currBytes));

-    int i;

-    

-    /*

-     * Copy from the old literal array to the new, then update the local

-     * literal table's bucket array.

-     */

-

-    memcpy((VOID *) newArrayPtr, (VOID *) currArrayPtr, currBytes);

-    for (i = 0;  i < currElems;  i++) {

-	if (currArrayPtr[i].nextPtr == NULL) {

-	    newArrayPtr[i].nextPtr = NULL;

-	} else {

-	    newArrayPtr[i].nextPtr = newArrayPtr

-		    + (currArrayPtr[i].nextPtr - currArrayPtr);

-	}

-    }

-    for (i = 0;  i < localTablePtr->numBuckets;  i++) {

-	if (localTablePtr->buckets[i] != NULL) {

-	    localTablePtr->buckets[i] = newArrayPtr

-	            + (localTablePtr->buckets[i] - currArrayPtr);

-	}

-    }

-

-    /*

-     * Free the old literal array if needed, and mark the new literal

-     * array as malloced.

-     */

-    

-    if (envPtr->mallocedLiteralArray) {

-	ckfree((char *) currArrayPtr);

-    }

-    envPtr->literalArrayPtr = newArrayPtr;

-    envPtr->literalArrayEnd = (2 * currElems);

-    envPtr->mallocedLiteralArray = 1;

-}

-

-/*

- *----------------------------------------------------------------------

- *

- * TclReleaseLiteral --

- *

- *	This procedure releases a reference to one of the shared Tcl objects

- *	that hold literals. It is called to release the literals referenced

- *	by a ByteCode that is being destroyed, and it is also called by

- *	TclDeleteLiteralTable.

- *

- * Results:

- *	None.

- *

- * Side effects:

- *	The reference count for the global LiteralTable entry that 

- *	corresponds to the literal is decremented. If no other reference

- *	to a global literal object remains, it is freed.

- *

- *----------------------------------------------------------------------

- */

-

-void

-TclReleaseLiteral(interp, objPtr)

-    Tcl_Interp *interp;		/* Interpreter for which objPtr was created

-				 * to hold a literal. */

-    register Tcl_Obj *objPtr;	/* Points to a literal object that was

-				 * previously created by a call to

-				 * TclRegisterLiteral. */

-{

-    Interp *iPtr = (Interp *) interp;

-    LiteralTable *globalTablePtr = &(iPtr->literalTable);

-    register LiteralEntry *entryPtr, *prevPtr;

-    ByteCode* codePtr;

-    char *bytes;

-    int length, index;

-

-    bytes = Tcl_GetStringFromObj(objPtr, &length);

-    index = (HashString(bytes, length) & globalTablePtr->mask);

-

-    /*

-     * Check to see if the object is in the global literal table and 

-     * remove this reference.  The object may not be in the table if

-     * it is a hidden local literal.

-     */

-

-    for (prevPtr = NULL, entryPtr = globalTablePtr->buckets[index];

-	    entryPtr != NULL;

-	    prevPtr = entryPtr, entryPtr = entryPtr->nextPtr) {

-	if (entryPtr->objPtr == objPtr) {

-	    entryPtr->refCount--;

-

-	    /*

-	     * We found the matching LiteralEntry. Check if it's only being

-	     * kept alive only by a circular reference from a ByteCode

-	     * stored as its internal rep.

-	     */

-	    

-	    if ((entryPtr->refCount == 1)

-		    && (objPtr->typePtr == &tclByteCodeType)) {

-		codePtr = (ByteCode *) objPtr->internalRep.otherValuePtr;

-		if ((codePtr->numLitObjects == 1)

-		        && (codePtr->objArrayPtr[0] == objPtr)) {

-		    entryPtr->refCount = 0;

-

-		    /*

-		     * Set the ByteCode object array entry NULL to signal

-		     * to TclCleanupByteCode to not try to release this

-		     * about to be freed literal again.

-		     */

-

-		    codePtr->objArrayPtr[0] = NULL;

-		}

-	    }

-

-	    /*

-	     * If the literal is no longer being used by any ByteCode,

-	     * delete the entry then decrement the ref count of its object.

-	     */

-		

-	    if (entryPtr->refCount == 0) {

-		if (prevPtr == NULL) {

-		    globalTablePtr->buckets[index] = entryPtr->nextPtr;

-		} else {

-		    prevPtr->nextPtr = entryPtr->nextPtr;

-		}

-#ifdef TCL_COMPILE_STATS

-		iPtr->stats.currentLitStringBytes -= (double) (length + 1);

-#endif /*TCL_COMPILE_STATS*/

-		ckfree((char *) entryPtr);

-		globalTablePtr->numEntries--;

-

-		/*

-		 * Remove the reference corresponding to the global 

-		 * literal table entry.

-		 */

-

-		TclDecrRefCount(objPtr);

-	    }

-	    break;

-	}

-    }

-

-    /*

-     * Remove the reference corresponding to the local literal table

-     * entry.

-     */

-

-    Tcl_DecrRefCount(objPtr);

-}

-

-/*

- *----------------------------------------------------------------------

- *

- * HashString --

- *

- *	Compute a one-word summary of a text string, which can be

- *	used to generate a hash index.

- *

- * Results:

- *	The return value is a one-word summary of the information in

- *	string.

- *

- * Side effects:

- *	None.

- *

- *----------------------------------------------------------------------

- */

-

-static unsigned int

-HashString(bytes, length)

-    register CONST char *bytes; /* String for which to compute hash

-				 * value. */

-    int length;			/* Number of bytes in the string. */

-{

-    register unsigned int result;

-    register int i;

-

-    /*

-     * I tried a zillion different hash functions and asked many other

-     * people for advice.  Many people had their own favorite functions,

-     * all different, but no-one had much idea why they were good ones.

-     * I chose the one below (multiply by 9 and add new character)

-     * because of the following reasons:

-     *

-     * 1. Multiplying by 10 is perfect for keys that are decimal strings,

-     *    and multiplying by 9 is just about as good.

-     * 2. Times-9 is (shift-left-3) plus (old).  This means that each

-     *    character's bits hang around in the low-order bits of the

-     *    hash value for ever, plus they spread fairly rapidly up to

-     *    the high-order bits to fill out the hash value.  This seems

-     *    works well both for decimal and non-decimal strings.

-     */

-

-    result = 0;

-    for (i = 0;  i < length;  i++) {

-	result += (result<<3) + *bytes++;

-    }

-    return result;

-}

-

-/*

- *----------------------------------------------------------------------

- *

- * RebuildLiteralTable --

- *

- *	This procedure is invoked when the ratio of entries to hash buckets

- *	becomes too large in a local or global literal table. It allocates

- *	a larger bucket array and moves the entries into the new buckets.

- *

- * Results:

- *	None.

- *

- * Side effects:

- *	Memory gets reallocated and entries get rehashed into new buckets.

- *

- *----------------------------------------------------------------------

- */

-

-static void

-RebuildLiteralTable(tablePtr)

-    register LiteralTable *tablePtr; /* Local or global table to enlarge. */

-{

-    LiteralEntry **oldBuckets;

-    register LiteralEntry **oldChainPtr, **newChainPtr;

-    register LiteralEntry *entryPtr;

-    LiteralEntry **bucketPtr;

-    char *bytes;

-    int oldSize, count, index, length;

-

-    oldSize = tablePtr->numBuckets;

-    oldBuckets = tablePtr->buckets;

-

-    /*

-     * Allocate and initialize the new bucket array, and set up

-     * hashing constants for new array size.

-     */

-

-    tablePtr->numBuckets *= 4;

-    tablePtr->buckets = (LiteralEntry **) ckalloc((unsigned)

-	    (tablePtr->numBuckets * sizeof(LiteralEntry *)));

-    for (count = tablePtr->numBuckets, newChainPtr = tablePtr->buckets;

-	    count > 0;

-	    count--, newChainPtr++) {

-	*newChainPtr = NULL;

-    }

-    tablePtr->rebuildSize *= 4;

-    tablePtr->mask = (tablePtr->mask << 2) + 3;

-

-    /*

-     * Rehash all of the existing entries into the new bucket array.

-     */

-

-    for (oldChainPtr = oldBuckets;

-	    oldSize > 0;

-	    oldSize--, oldChainPtr++) {

-	for (entryPtr = *oldChainPtr;  entryPtr != NULL;

-	        entryPtr = *oldChainPtr) {

-	    bytes = Tcl_GetStringFromObj(entryPtr->objPtr, &length);

-	    index = (HashString(bytes, length) & tablePtr->mask);

-	    

-	    *oldChainPtr = entryPtr->nextPtr;

-	    bucketPtr = &(tablePtr->buckets[index]);

-	    entryPtr->nextPtr = *bucketPtr;

-	    *bucketPtr = entryPtr;

-	}

-    }

-

-    /*

-     * Free up the old bucket array, if it was dynamically allocated.

-     */

-

-    if (oldBuckets != tablePtr->staticBuckets) {

-	ckfree((char *) oldBuckets);

-    }

-}

-

-#ifdef TCL_COMPILE_STATS

-/*

- *----------------------------------------------------------------------

- *

- * TclLiteralStats --

- *

- *	Return statistics describing the layout of the hash table

- *	in its hash buckets.

- *

- * Results:

- *	The return value is a malloc-ed string containing information

- *	about tablePtr.  It is the caller's responsibility to free

- *	this string.

- *

- * Side effects:

- *	None.

- *

- *----------------------------------------------------------------------

- */

-

-char *

-TclLiteralStats(tablePtr)

-    LiteralTable *tablePtr;	/* Table for which to produce stats. */

-{

-#define NUM_COUNTERS 10

-    int count[NUM_COUNTERS], overflow, i, j;

-    double average, tmp;

-    register LiteralEntry *entryPtr;

-    char *result, *p;

-

-    /*

-     * Compute a histogram of bucket usage. For each bucket chain i,

-     * j is the number of entries in the chain.

-     */

-

-    for (i = 0;  i < NUM_COUNTERS;  i++) {

-	count[i] = 0;

-    }

-    overflow = 0;

-    average = 0.0;

-    for (i = 0;  i < tablePtr->numBuckets;  i++) {

-	j = 0;

-	for (entryPtr = tablePtr->buckets[i];  entryPtr != NULL;

-	        entryPtr = entryPtr->nextPtr) {

-	    j++;

-	}

-	if (j < NUM_COUNTERS) {

-	    count[j]++;

-	} else {

-	    overflow++;

-	}

-	tmp = j;

-	average += (tmp+1.0)*(tmp/tablePtr->numEntries)/2.0;

-    }

-

-    /*

-     * Print out the histogram and a few other pieces of information.

-     */

-

-    result = (char *) ckalloc((unsigned) ((NUM_COUNTERS*60) + 300));

-    sprintf(result, "%d entries in table, %d buckets\n",

-	    tablePtr->numEntries, tablePtr->numBuckets);

-    p = result + strlen(result);

-    for (i = 0; i < NUM_COUNTERS; i++) {

-	sprintf(p, "number of buckets with %d entries: %d\n",

-		i, count[i]);

-	p += strlen(p);

-    }

-    sprintf(p, "number of buckets with %d or more entries: %d\n",

-	    NUM_COUNTERS, overflow);

-    p += strlen(p);

-    sprintf(p, "average search distance for entry: %.1f", average);

-    return result;

-}

-#endif /*TCL_COMPILE_STATS*/

-

-#ifdef TCL_COMPILE_DEBUG

-/*

- *----------------------------------------------------------------------

- *

- * TclVerifyLocalLiteralTable --

- *

- *	Check a CompileEnv's local literal table for consistency.

- *

- * Results:

- *	None.

- *

- * Side effects:

- *	Panics if problems are found.

- *

- *----------------------------------------------------------------------

- */

-

-void

-TclVerifyLocalLiteralTable(envPtr)

-    CompileEnv *envPtr;		/* Points to CompileEnv whose literal

-				 * table is to be validated. */

-{

-    register LiteralTable *localTablePtr = &(envPtr->localLitTable);

-    register LiteralEntry *localPtr;

-    char *bytes;

-    register int i;

-    int length, count;

-

-    count = 0;

-    for (i = 0;  i < localTablePtr->numBuckets;  i++) {

-	for (localPtr = localTablePtr->buckets[i];

-	        localPtr != NULL;  localPtr = localPtr->nextPtr) {

-	    count++;

-	    if (localPtr->refCount != -1) {

-		bytes = Tcl_GetStringFromObj(localPtr->objPtr, &length);

-		panic("TclVerifyLocalLiteralTable: local literal \"%.*s\" had bad refCount %d",

-		        (length>60? 60 : length), bytes,

-		        localPtr->refCount);

-	    }

-	    if (TclLookupLiteralEntry((Tcl_Interp *) envPtr->iPtr,

-		    localPtr->objPtr) == NULL) {

-		bytes = Tcl_GetStringFromObj(localPtr->objPtr, &length);

-		panic("TclVerifyLocalLiteralTable: local literal \"%.*s\" is not global",

-		         (length>60? 60 : length), bytes);

-	    }

-	    if (localPtr->objPtr->bytes == NULL) {

-		panic("TclVerifyLocalLiteralTable: literal has NULL string rep");

-	    }

-	}

-    }

-    if (count != localTablePtr->numEntries) {

-	panic("TclVerifyLocalLiteralTable: local literal table had %d entries, should be %d",

-	      count, localTablePtr->numEntries);

-    }

-}

-

-/*

- *----------------------------------------------------------------------

- *

- * TclVerifyGlobalLiteralTable --

- *

- *	Check an interpreter's global literal table literal for consistency.

- *

- * Results:

- *	None.

- *

- * Side effects:

- *	Panics if problems are found.

- *

- *----------------------------------------------------------------------

- */

-

-void

-TclVerifyGlobalLiteralTable(iPtr)

-    Interp *iPtr;		/* Points to interpreter whose global

-				 * literal table is to be validated. */

-{

-    register LiteralTable *globalTablePtr = &(iPtr->literalTable);

-    register LiteralEntry *globalPtr;

-    char *bytes;

-    register int i;

-    int length, count;

-

-    count = 0;

-    for (i = 0;  i < globalTablePtr->numBuckets;  i++) {

-	for (globalPtr = globalTablePtr->buckets[i];

-	        globalPtr != NULL;  globalPtr = globalPtr->nextPtr) {

-	    count++;

-	    if (globalPtr->refCount < 1) {

-		bytes = Tcl_GetStringFromObj(globalPtr->objPtr, &length);

-		panic("TclVerifyGlobalLiteralTable: global literal \"%.*s\" had bad refCount %d",

-		        (length>60? 60 : length), bytes,

-		        globalPtr->refCount);

-	    }

-	    if (globalPtr->objPtr->bytes == NULL) {

-		panic("TclVerifyGlobalLiteralTable: literal has NULL string rep");

-	    }

-	}

-    }

-    if (count != globalTablePtr->numEntries) {

-	panic("TclVerifyGlobalLiteralTable: global literal table had %d entries, should be %d",

-	      count, globalTablePtr->numEntries);

-    }

-}

-#endif /*TCL_COMPILE_DEBUG*/

+/* 
+ * tclLiteral.c --
+ *
+ *	Implementation of the global and ByteCode-local literal tables
+ *	used to manage the Tcl objects created for literal values during
+ *	compilation of Tcl scripts. This implementation borrows heavily
+ *	from the more general hashtable implementation of Tcl hash tables
+ *	that appears in tclHash.c.
+ *
+ * Copyright (c) 1997-1998 Sun Microsystems, Inc.
+ *
+ * See the file "license.terms" for information on usage and redistribution
+ * of this file, and for a DISCLAIMER OF ALL WARRANTIES.
+ *
+ * RCS: @(#) $Id: tclLiteral.c,v 1.6 1999/05/06 02:34:42 hershey Exp $
+ */
+
+#include "tclInt.h"
+#include "tclCompile.h"
+#include "tclPort.h"
+/*
+ * When there are this many entries per bucket, on average, rebuild
+ * a literal's hash table to make it larger.
+ */
+
+#define REBUILD_MULTIPLIER	3
+
+/*
+ * Procedure prototypes for static procedures in this file:
+ */
+
+static int		AddLocalLiteralEntry _ANSI_ARGS_((
+			    CompileEnv *envPtr, LiteralEntry *globalPtr,
+			    int localHash));
+static void		ExpandLocalLiteralArray _ANSI_ARGS_((
+			    CompileEnv *envPtr));
+static unsigned int	HashString _ANSI_ARGS_((CONST char *bytes,
+			    int length));
+static void		RebuildLiteralTable _ANSI_ARGS_((
+			    LiteralTable *tablePtr));
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * TclInitLiteralTable --
+ *
+ *	This procedure is called to initialize the fields of a literal table
+ *	structure for either an interpreter or a compilation's CompileEnv
+ *	structure.
+ *
+ * Results:
+ *	None.
+ *
+ * Side effects: 
+ *	The literal table is made ready for use.
+ *
+ *----------------------------------------------------------------------
+ */
+
+void
+TclInitLiteralTable(tablePtr)
+    register LiteralTable *tablePtr; /* Pointer to table structure, which
+				      * is supplied by the caller. */
+{
+#if (TCL_SMALL_HASH_TABLE != 4) 
+    panic("TclInitLiteralTable: TCL_SMALL_HASH_TABLE is %d, not 4\n",
+	    TCL_SMALL_HASH_TABLE);
+#endif
+    
+    tablePtr->buckets = tablePtr->staticBuckets;
+    tablePtr->staticBuckets[0] = tablePtr->staticBuckets[1] = 0;
+    tablePtr->staticBuckets[2] = tablePtr->staticBuckets[3] = 0;
+    tablePtr->numBuckets = TCL_SMALL_HASH_TABLE;
+    tablePtr->numEntries = 0;
+    tablePtr->rebuildSize = TCL_SMALL_HASH_TABLE*REBUILD_MULTIPLIER;
+    tablePtr->mask = 3;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * TclDeleteLiteralTable --
+ *
+ *	This procedure frees up everything associated with a literal table
+ *	except for the table's structure itself.
+ *
+ * Results:
+ *	None.
+ *
+ * Side effects:
+ *	Each literal in the table is released: i.e., its reference count
+ *	in the global literal table is decremented and, if it becomes zero,
+ *	the literal is freed. In addition, the table's bucket array is
+ *	freed.
+ *
+ *----------------------------------------------------------------------
+ */
+
+void
+TclDeleteLiteralTable(interp, tablePtr)
+    Tcl_Interp *interp;		/* Interpreter containing shared literals
+				 * referenced by the table to delete. */
+    LiteralTable *tablePtr;	/* Points to the literal table to delete. */
+{
+    LiteralEntry *entryPtr;
+    int i, start;
+
+    /*
+     * Release remaining literals in the table. Note that releasing a
+     * literal might release other literals, modifying the table, so we
+     * restart the search from the bucket chain we last found an entry.
+     */
+
+#ifdef TCL_COMPILE_DEBUG
+    TclVerifyGlobalLiteralTable((Interp *) interp);
+#endif /*TCL_COMPILE_DEBUG*/
+
+    start = 0;
+    while (tablePtr->numEntries > 0) {
+	for (i = start;  i < tablePtr->numBuckets;  i++) {
+	    entryPtr = tablePtr->buckets[i];
+	    if (entryPtr != NULL) {
+		TclReleaseLiteral(interp, entryPtr->objPtr);
+		start = i;
+		break;
+	    }
+	}
+    }
+
+    /*
+     * Free up the table's bucket array if it was dynamically allocated.
+     */
+
+    if (tablePtr->buckets != tablePtr->staticBuckets) {
+	ckfree((char *) tablePtr->buckets);
+    }
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * TclRegisterLiteral --
+ *
+ *	Find, or if necessary create, an object in a CompileEnv literal
+ *	array that has a string representation matching the argument string.
+ *
+ * Results:
+ *	The index in the CompileEnv's literal array that references a
+ *	shared literal matching the string. The object is created if
+ *	necessary.
+ *
+ * Side effects:
+ *	To maximize sharing, we look up the string in the interpreter's
+ *	global literal table. If not found, we create a new shared literal
+ *	in the global table. We then add a reference to the shared
+ *	literal in the CompileEnv's literal array. 
+ *
+ *	If onHeap is 1, this procedure is given ownership of the string: if
+ *	an object is created then its string representation is set directly
+ *	from string, otherwise the string is freed. Typically, a caller sets
+ *	onHeap 1 if "string" is an already heap-allocated buffer holding the
+ *	result of backslash substitutions.
+ *
+ *----------------------------------------------------------------------
+ */
+
+int
+TclRegisterLiteral(envPtr, bytes, length, onHeap)
+    CompileEnv *envPtr;		/* Points to the CompileEnv in whose object
+				 * array an object is found or created. */
+    register char *bytes;	/* Points to string for which to find or
+				 * create an object in CompileEnv's object
+				 * array. */
+    int length;			/* Number of bytes in the string. If < 0,
+				 * the string consists of all bytes up to
+				 * the first null character. */
+    int onHeap;			/* If 1 then the caller already malloc'd
+				 * bytes and ownership is passed to this
+				 * procedure. */
+{
+    Interp *iPtr = envPtr->iPtr;
+    LiteralTable *globalTablePtr = &(iPtr->literalTable);
+    LiteralTable *localTablePtr = &(envPtr->localLitTable);
+    register LiteralEntry *globalPtr, *localPtr;
+    register Tcl_Obj *objPtr;
+    unsigned int hash;
+    int localHash, globalHash, objIndex;
+    long n;
+    char buf[TCL_INTEGER_SPACE];
+
+ 
+    if (length < 0) {
+	length = (bytes? strlen(bytes) : 0);
+    }
+    hash = HashString(bytes, length);
+
+    /*
+     * Is the literal already in the CompileEnv's local literal array?
+     * If so, just return its index.
+     */
+
+    localHash = (hash & localTablePtr->mask);
+    for (localPtr = localTablePtr->buckets[localHash];
+	  localPtr != NULL;  localPtr = localPtr->nextPtr) {
+	objPtr = localPtr->objPtr;
+	if ((objPtr->length == length) && ((length == 0)
+		|| ((objPtr->bytes[0] == bytes[0])
+			&& (memcmp(objPtr->bytes, bytes, (unsigned) length)
+				== 0)))) {
+	    if (onHeap) {
+		ckfree(bytes);
+	    }
+	    objIndex = (localPtr - envPtr->literalArrayPtr);
+#ifdef TCL_COMPILE_DEBUG
+	    TclVerifyLocalLiteralTable(envPtr);
+#endif /*TCL_COMPILE_DEBUG*/
+
+	    return objIndex;
+	}
+    }
+
+    /*
+     * The literal is new to this CompileEnv. Is it in the interpreter's
+     * global literal table?
+     */
+
+    globalHash = (hash & globalTablePtr->mask);
+    for (globalPtr = globalTablePtr->buckets[globalHash];
+	 globalPtr != NULL;  globalPtr = globalPtr->nextPtr) {
+	objPtr = globalPtr->objPtr;
+	if ((objPtr->length == length) && ((length == 0)
+		|| ((objPtr->bytes[0] == bytes[0])
+			&& (memcmp(objPtr->bytes, bytes, (unsigned) length)
+				== 0)))) {
+	    /*
+	     * A global literal was found. Add an entry to the CompileEnv's
+	     * local literal array.
+	     */
+	    
+	    if (onHeap) {
+		ckfree(bytes);
+	    }
+	    objIndex = AddLocalLiteralEntry(envPtr, globalPtr, localHash);
+#ifdef TCL_COMPILE_DEBUG
+	    if (globalPtr->refCount < 1) {
+		panic("TclRegisterLiteral: global literal \"%.*s\" had bad refCount %d",
+			(length>60? 60 : length), bytes,
+			globalPtr->refCount);
+	    }
+	    TclVerifyLocalLiteralTable(envPtr);
+#endif /*TCL_COMPILE_DEBUG*/ 
+	    return objIndex;
+	}
+    }
+
+    /*
+     * The literal is new to the interpreter. Add it to the global literal
+     * table then add an entry to the CompileEnv's local literal array.
+     * Convert the object to an integer object if possible.
+     */
+
+    TclNewObj(objPtr);
+    Tcl_IncrRefCount(objPtr);
+    if (onHeap) {
+	objPtr->bytes = bytes;
+	objPtr->length = length;
+    } else {
+	TclInitStringRep(objPtr, bytes, length);
+    }
+
+    if (TclLooksLikeInt(bytes, length)) {
+	if (TclGetLong((Tcl_Interp *) NULL, bytes, &n) == TCL_OK) {
+	    TclFormatInt(buf, n);
+	    if (strcmp(bytes, buf) == 0) {
+		objPtr->internalRep.longValue = n;
+		objPtr->typePtr = &tclIntType;
+	    }
+	}
+    }
+    
+#ifdef TCL_COMPILE_DEBUG
+    if (TclLookupLiteralEntry((Tcl_Interp *) iPtr, objPtr) != NULL) {
+	panic("TclRegisterLiteral: literal \"%.*s\" found globally but shouldn't be",
+	        (length>60? 60 : length), bytes);
+    }
+#endif
+
+    globalPtr = (LiteralEntry *) ckalloc((unsigned) sizeof(LiteralEntry));
+    globalPtr->objPtr = objPtr;
+    globalPtr->refCount = 0;
+    globalPtr->nextPtr = globalTablePtr->buckets[globalHash];
+    globalTablePtr->buckets[globalHash] = globalPtr;
+    globalTablePtr->numEntries++;
+
+    /*
+     * If the global literal table has exceeded a decent size, rebuild it
+     * with more buckets.
+     */
+
+    if (globalTablePtr->numEntries >= globalTablePtr->rebuildSize) {
+	RebuildLiteralTable(globalTablePtr);
+    }
+    
+    objIndex = AddLocalLiteralEntry(envPtr, globalPtr, localHash);
+
+#ifdef TCL_COMPILE_DEBUG
+    TclVerifyGlobalLiteralTable(iPtr);
+    TclVerifyLocalLiteralTable(envPtr);
+    {
+	LiteralEntry *entryPtr;
+	int found, i;
+	found = 0;
+	for (i = 0;  i < globalTablePtr->numBuckets;  i++) {
+	    for (entryPtr = globalTablePtr->buckets[i];
+		    entryPtr != NULL;  entryPtr = entryPtr->nextPtr) {
+		if ((entryPtr == globalPtr)
+		        && (entryPtr->objPtr == objPtr)) {
+		    found = 1;
+		}
+	    }
+	}
+	if (!found) {
+	    panic("TclRegisterLiteral: literal \"%.*s\" wasn't global",
+	            (length>60? 60 : length), bytes);
+	}
+    }
+#endif /*TCL_COMPILE_DEBUG*/
+#ifdef TCL_COMPILE_STATS   
+    iPtr->stats.numLiteralsCreated++;
+    iPtr->stats.totalLitStringBytes   += (double) (length + 1);
+    iPtr->stats.currentLitStringBytes += (double) (length + 1);
+    iPtr->stats.literalCount[TclLog2(length)]++;
+#endif /*TCL_COMPILE_STATS*/
+    return objIndex;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * TclLookupLiteralEntry --
+ *
+ *	Finds the LiteralEntry that corresponds to a literal Tcl object
+ *      holding a literal.
+ *
+ * Results:
+ *      Returns the matching LiteralEntry if found, otherwise NULL.
+ *
+ * Side effects:
+ *      None.
+ *
+ *----------------------------------------------------------------------
+ */
+
+LiteralEntry *
+TclLookupLiteralEntry(interp, objPtr)
+    Tcl_Interp *interp;		/* Interpreter for which objPtr was created
+                                 * to hold a literal. */
+    register Tcl_Obj *objPtr;	/* Points to a Tcl object holding a
+                                 * literal that was previously created by a
+                                 * call to TclRegisterLiteral. */
+{
+    Interp *iPtr = (Interp *) interp;
+    LiteralTable *globalTablePtr = &(iPtr->literalTable);
+    register LiteralEntry *entryPtr;
+    char *bytes;
+    int length, globalHash;
+
+    bytes = Tcl_GetStringFromObj(objPtr, &length);
+    globalHash = (HashString(bytes, length) & globalTablePtr->mask);
+    for (entryPtr = globalTablePtr->buckets[globalHash];
+            entryPtr != NULL;  entryPtr = entryPtr->nextPtr) {
+        if (entryPtr->objPtr == objPtr) {
+            return entryPtr;
+        }
+    }
+    return NULL;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * TclHideLiteral --
+ *
+ *	Remove a literal entry from the literal hash tables, leaving it in
+ *	the literal array so existing references continue to function.
+ *	This makes it possible to turn a shared literal into a private
+ *	literal that cannot be shared.
+ *
+ * Results:
+ *	None.
+ *
+ * Side effects:
+ *	Removes the literal from the local hash table and decrements the
+ *	global hash entry's reference count.
+ *
+ *----------------------------------------------------------------------
+ */
+
+void
+TclHideLiteral(interp, envPtr, index)
+    Tcl_Interp *interp;		 /* Interpreter for which objPtr was created
+                                  * to hold a literal. */
+    register CompileEnv *envPtr; /* Points to CompileEnv whose literal array
+				  * contains the entry being hidden. */
+    int index;			 /* The index of the entry in the literal
+				  * array. */
+{
+    LiteralEntry **nextPtrPtr, *entryPtr, *lPtr;
+    LiteralTable *localTablePtr = &(envPtr->localLitTable);
+    int localHash, length;
+    char *bytes;
+    Tcl_Obj *newObjPtr;
+
+    lPtr = &(envPtr->literalArrayPtr[index]);
+
+    /*
+     * To avoid unwanted sharing we need to copy the object and remove it from
+     * the local and global literal tables.  It still has a slot in the literal
+     * array so it can be referred to by byte codes, but it will not be matched
+     * by literal searches.
+     */
+
+    newObjPtr = Tcl_DuplicateObj(lPtr->objPtr);
+    Tcl_IncrRefCount(newObjPtr);
+    TclReleaseLiteral(interp, lPtr->objPtr);
+    lPtr->objPtr = newObjPtr;
+
+    bytes = Tcl_GetStringFromObj(newObjPtr, &length);
+    localHash = (HashString(bytes, length) & localTablePtr->mask);
+    nextPtrPtr = &localTablePtr->buckets[localHash];
+
+    for (entryPtr = *nextPtrPtr; entryPtr != NULL; entryPtr = *nextPtrPtr) {
+	if (entryPtr == lPtr) {
+	    *nextPtrPtr = lPtr->nextPtr;
+	    lPtr->nextPtr = NULL;
+	    localTablePtr->numEntries--;
+	    break;
+	}
+	nextPtrPtr = &entryPtr->nextPtr;
+    }
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * TclAddLiteralObj --
+ *
+ *	Add a single literal object to the literal array.  This
+ *	function does not add the literal to the local or global
+ *	literal tables.  The caller is expected to add the entry
+ *	to whatever tables are appropriate.
+ *
+ * Results:
+ *	The index in the CompileEnv's literal array that references the
+ *	literal.  Stores the pointer to the new literal entry in the
+ *	location referenced by the localPtrPtr argument.
+ *
+ * Side effects:
+ *	Expands the literal array if necessary.  Increments the refcount
+ *	on the literal object.
+ *
+ *----------------------------------------------------------------------
+ */
+
+int
+TclAddLiteralObj(envPtr, objPtr, litPtrPtr)
+    register CompileEnv *envPtr; /* Points to CompileEnv in whose literal
+				  * array the object is to be inserted. */
+    Tcl_Obj *objPtr;		 /* The object to insert into the array. */
+    LiteralEntry **litPtrPtr;	 /* The location where the pointer to the
+				  * new literal entry should be stored.
+				  * May be NULL. */
+{
+    register LiteralEntry *lPtr;
+    int objIndex;
+
+    if (envPtr->literalArrayNext >= envPtr->literalArrayEnd) {
+	ExpandLocalLiteralArray(envPtr);
+    }
+    objIndex = envPtr->literalArrayNext;
+    envPtr->literalArrayNext++;
+
+    lPtr = &(envPtr->literalArrayPtr[objIndex]);
+    lPtr->objPtr = objPtr;
+    Tcl_IncrRefCount(objPtr);
+    lPtr->refCount = -1;	/* i.e., unused */
+    lPtr->nextPtr = NULL;
+
+    if (litPtrPtr) {
+	*litPtrPtr = lPtr;
+    }
+
+    return objIndex;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * AddLocalLiteralEntry --
+ *
+ *	Insert a new literal into a CompileEnv's local literal array.
+ *
+ * Results:
+ *	The index in the CompileEnv's literal array that references the
+ *	literal.
+ *
+ * Side effects:
+ *	Increments the ref count of the global LiteralEntry since the
+ *	CompileEnv now refers to the literal. Expands the literal array
+ *	if necessary. May rebuild the hash bucket array of the CompileEnv's
+ *	literal array if it becomes too large.
+ *
+ *----------------------------------------------------------------------
+ */
+
+static int
+AddLocalLiteralEntry(envPtr, globalPtr, localHash)
+    register CompileEnv *envPtr; /* Points to CompileEnv in whose literal
+				  * array the object is to be inserted. */
+    LiteralEntry *globalPtr;	 /* Points to the global LiteralEntry for
+				  * the literal to add to the CompileEnv. */
+    int localHash;		 /* Hash value for the literal's string. */
+{
+    register LiteralTable *localTablePtr = &(envPtr->localLitTable);
+    LiteralEntry *localPtr;
+    int objIndex;
+    
+    objIndex = TclAddLiteralObj(envPtr, globalPtr->objPtr, &localPtr);
+
+    /*
+     * Add the literal to the local table.
+     */
+
+    localPtr->nextPtr = localTablePtr->buckets[localHash];
+    localTablePtr->buckets[localHash] = localPtr;
+    localTablePtr->numEntries++;
+
+    globalPtr->refCount++;
+
+    /*
+     * If the CompileEnv's local literal table has exceeded a decent size,
+     * rebuild it with more buckets.
+     */
+
+    if (localTablePtr->numEntries >= localTablePtr->rebuildSize) {
+	RebuildLiteralTable(localTablePtr);
+    }
+
+#ifdef TCL_COMPILE_DEBUG
+    TclVerifyLocalLiteralTable(envPtr);
+    {
+	char *bytes;
+	int length, found, i;
+	found = 0;
+	for (i = 0;  i < localTablePtr->numBuckets;  i++) {
+	    for (localPtr = localTablePtr->buckets[i];
+		    localPtr != NULL;  localPtr = localPtr->nextPtr) {
+		if (localPtr->objPtr == globalPtr->objPtr) {
+		    found = 1;
+		}
+	    }
+	}
+	if (!found) {
+	    bytes = Tcl_GetStringFromObj(globalPtr->objPtr, &length);
+	    panic("AddLocalLiteralEntry: literal \"%.*s\" wasn't found locally",
+	            (length>60? 60 : length), bytes);
+	}
+    }
+#endif /*TCL_COMPILE_DEBUG*/
+    return objIndex;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * ExpandLocalLiteralArray --
+ *
+ *	Procedure that uses malloc to allocate more storage for a
+ *	CompileEnv's local literal array.
+ *
+ * Results:
+ *	None.
+ *
+ * Side effects:
+ *	The literal array in *envPtr is reallocated to a new array of
+ *	double the size, and if envPtr->mallocedLiteralArray is non-zero
+ *	the old array is freed. Entries are copied from the old array
+ *	to the new one. The local literal table is updated to refer to
+ *	the new entries.
+ *
+ *----------------------------------------------------------------------
+ */
+
+static void
+ExpandLocalLiteralArray(envPtr)
+    register CompileEnv *envPtr; /* Points to the CompileEnv whose object
+				  * array must be enlarged. */
+{
+    /*
+     * The current allocated local literal entries are stored between
+     * elements 0 and (envPtr->literalArrayNext - 1) [inclusive].
+     */
+
+    LiteralTable *localTablePtr = &(envPtr->localLitTable);
+    int currElems = envPtr->literalArrayNext;
+    size_t currBytes = (currElems * sizeof(LiteralEntry));
+    register LiteralEntry *currArrayPtr = envPtr->literalArrayPtr;
+    register LiteralEntry *newArrayPtr =
+	    (LiteralEntry *) ckalloc((unsigned) (2 * currBytes));
+    int i;
+    
+    /*
+     * Copy from the old literal array to the new, then update the local
+     * literal table's bucket array.
+     */
+
+    memcpy((VOID *) newArrayPtr, (VOID *) currArrayPtr, currBytes);
+    for (i = 0;  i < currElems;  i++) {
+	if (currArrayPtr[i].nextPtr == NULL) {
+	    newArrayPtr[i].nextPtr = NULL;
+	} else {
+	    newArrayPtr[i].nextPtr = newArrayPtr
+		    + (currArrayPtr[i].nextPtr - currArrayPtr);
+	}
+    }
+    for (i = 0;  i < localTablePtr->numBuckets;  i++) {
+	if (localTablePtr->buckets[i] != NULL) {
+	    localTablePtr->buckets[i] = newArrayPtr
+	            + (localTablePtr->buckets[i] - currArrayPtr);
+	}
+    }
+
+    /*
+     * Free the old literal array if needed, and mark the new literal
+     * array as malloced.
+     */
+    
+    if (envPtr->mallocedLiteralArray) {
+	ckfree((char *) currArrayPtr);
+    }
+    envPtr->literalArrayPtr = newArrayPtr;
+    envPtr->literalArrayEnd = (2 * currElems);
+    envPtr->mallocedLiteralArray = 1;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * TclReleaseLiteral --
+ *
+ *	This procedure releases a reference to one of the shared Tcl objects
+ *	that hold literals. It is called to release the literals referenced
+ *	by a ByteCode that is being destroyed, and it is also called by
+ *	TclDeleteLiteralTable.
+ *
+ * Results:
+ *	None.
+ *
+ * Side effects:
+ *	The reference count for the global LiteralTable entry that 
+ *	corresponds to the literal is decremented. If no other reference
+ *	to a global literal object remains, it is freed.
+ *
+ *----------------------------------------------------------------------
+ */
+
+void
+TclReleaseLiteral(interp, objPtr)
+    Tcl_Interp *interp;		/* Interpreter for which objPtr was created
+				 * to hold a literal. */
+    register Tcl_Obj *objPtr;	/* Points to a literal object that was
+				 * previously created by a call to
+				 * TclRegisterLiteral. */
+{
+    Interp *iPtr = (Interp *) interp;
+    LiteralTable *globalTablePtr = &(iPtr->literalTable);
+    register LiteralEntry *entryPtr, *prevPtr;
+    ByteCode* codePtr;
+    char *bytes;
+    int length, index;
+
+    bytes = Tcl_GetStringFromObj(objPtr, &length);
+    index = (HashString(bytes, length) & globalTablePtr->mask);
+
+    /*
+     * Check to see if the object is in the global literal table and 
+     * remove this reference.  The object may not be in the table if
+     * it is a hidden local literal.
+     */
+
+    for (prevPtr = NULL, entryPtr = globalTablePtr->buckets[index];
+	    entryPtr != NULL;
+	    prevPtr = entryPtr, entryPtr = entryPtr->nextPtr) {
+	if (entryPtr->objPtr == objPtr) {
+	    entryPtr->refCount--;
+
+	    /*
+	     * We found the matching LiteralEntry. Check if it's only being
+	     * kept alive only by a circular reference from a ByteCode
+	     * stored as its internal rep.
+	     */
+	    
+	    if ((entryPtr->refCount == 1)
+		    && (objPtr->typePtr == &tclByteCodeType)) {
+		codePtr = (ByteCode *) objPtr->internalRep.otherValuePtr;
+		if ((codePtr->numLitObjects == 1)
+		        && (codePtr->objArrayPtr[0] == objPtr)) {
+		    entryPtr->refCount = 0;
+
+		    /*
+		     * Set the ByteCode object array entry NULL to signal
+		     * to TclCleanupByteCode to not try to release this
+		     * about to be freed literal again.
+		     */
+
+		    codePtr->objArrayPtr[0] = NULL;
+		}
+	    }
+
+	    /*
+	     * If the literal is no longer being used by any ByteCode,
+	     * delete the entry then decrement the ref count of its object.
+	     */
+		
+	    if (entryPtr->refCount == 0) {
+		if (prevPtr == NULL) {
+		    globalTablePtr->buckets[index] = entryPtr->nextPtr;
+		} else {
+		    prevPtr->nextPtr = entryPtr->nextPtr;
+		}
+#ifdef TCL_COMPILE_STATS
+		iPtr->stats.currentLitStringBytes -= (double) (length + 1);
+#endif /*TCL_COMPILE_STATS*/
+		ckfree((char *) entryPtr);
+		globalTablePtr->numEntries--;
+
+		/*
+		 * Remove the reference corresponding to the global 
+		 * literal table entry.
+		 */
+
+		TclDecrRefCount(objPtr);
+	    }
+	    break;
+	}
+    }
+
+    /*
+     * Remove the reference corresponding to the local literal table
+     * entry.
+     */
+
+    Tcl_DecrRefCount(objPtr);
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * HashString --
+ *
+ *	Compute a one-word summary of a text string, which can be
+ *	used to generate a hash index.
+ *
+ * Results:
+ *	The return value is a one-word summary of the information in
+ *	string.
+ *
+ * Side effects:
+ *	None.
+ *
+ *----------------------------------------------------------------------
+ */
+
+static unsigned int
+HashString(bytes, length)
+    register CONST char *bytes; /* String for which to compute hash
+				 * value. */
+    int length;			/* Number of bytes in the string. */
+{
+    register unsigned int result;
+    register int i;
+
+    /*
+     * I tried a zillion different hash functions and asked many other
+     * people for advice.  Many people had their own favorite functions,
+     * all different, but no-one had much idea why they were good ones.
+     * I chose the one below (multiply by 9 and add new character)
+     * because of the following reasons:
+     *
+     * 1. Multiplying by 10 is perfect for keys that are decimal strings,
+     *    and multiplying by 9 is just about as good.
+     * 2. Times-9 is (shift-left-3) plus (old).  This means that each
+     *    character's bits hang around in the low-order bits of the
+     *    hash value for ever, plus they spread fairly rapidly up to
+     *    the high-order bits to fill out the hash value.  This seems
+     *    works well both for decimal and non-decimal strings.
+     */
+
+    result = 0;
+    for (i = 0;  i < length;  i++) {
+	result += (result<<3) + *bytes++;
+    }
+    return result;
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * RebuildLiteralTable --
+ *
+ *	This procedure is invoked when the ratio of entries to hash buckets
+ *	becomes too large in a local or global literal table. It allocates
+ *	a larger bucket array and moves the entries into the new buckets.
+ *
+ * Results:
+ *	None.
+ *
+ * Side effects:
+ *	Memory gets reallocated and entries get rehashed into new buckets.
+ *
+ *----------------------------------------------------------------------
+ */
+
+static void
+RebuildLiteralTable(tablePtr)
+    register LiteralTable *tablePtr; /* Local or global table to enlarge. */
+{
+    LiteralEntry **oldBuckets;
+    register LiteralEntry **oldChainPtr, **newChainPtr;
+    register LiteralEntry *entryPtr;
+    LiteralEntry **bucketPtr;
+    char *bytes;
+    int oldSize, count, index, length;
+
+    oldSize = tablePtr->numBuckets;
+    oldBuckets = tablePtr->buckets;
+
+    /*
+     * Allocate and initialize the new bucket array, and set up
+     * hashing constants for new array size.
+     */
+
+    tablePtr->numBuckets *= 4;
+    tablePtr->buckets = (LiteralEntry **) ckalloc((unsigned)
+	    (tablePtr->numBuckets * sizeof(LiteralEntry *)));
+    for (count = tablePtr->numBuckets, newChainPtr = tablePtr->buckets;
+	    count > 0;
+	    count--, newChainPtr++) {
+	*newChainPtr = NULL;
+    }
+    tablePtr->rebuildSize *= 4;
+    tablePtr->mask = (tablePtr->mask << 2) + 3;
+
+    /*
+     * Rehash all of the existing entries into the new bucket array.
+     */
+
+    for (oldChainPtr = oldBuckets;
+	    oldSize > 0;
+	    oldSize--, oldChainPtr++) {
+	for (entryPtr = *oldChainPtr;  entryPtr != NULL;
+	        entryPtr = *oldChainPtr) {
+	    bytes = Tcl_GetStringFromObj(entryPtr->objPtr, &length);
+	    index = (HashString(bytes, length) & tablePtr->mask);
+	    
+	    *oldChainPtr = entryPtr->nextPtr;
+	    bucketPtr = &(tablePtr->buckets[index]);
+	    entryPtr->nextPtr = *bucketPtr;
+	    *bucketPtr = entryPtr;
+	}
+    }
+
+    /*
+     * Free up the old bucket array, if it was dynamically allocated.
+     */
+
+    if (oldBuckets != tablePtr->staticBuckets) {
+	ckfree((char *) oldBuckets);
+    }
+}
+
+#ifdef TCL_COMPILE_STATS
+/*
+ *----------------------------------------------------------------------
+ *
+ * TclLiteralStats --
+ *
+ *	Return statistics describing the layout of the hash table
+ *	in its hash buckets.
+ *
+ * Results:
+ *	The return value is a malloc-ed string containing information
+ *	about tablePtr.  It is the caller's responsibility to free
+ *	this string.
+ *
+ * Side effects:
+ *	None.
+ *
+ *----------------------------------------------------------------------
+ */
+
+char *
+TclLiteralStats(tablePtr)
+    LiteralTable *tablePtr;	/* Table for which to produce stats. */
+{
+#define NUM_COUNTERS 10
+    int count[NUM_COUNTERS], overflow, i, j;
+    double average, tmp;
+    register LiteralEntry *entryPtr;
+    char *result, *p;
+
+    /*
+     * Compute a histogram of bucket usage. For each bucket chain i,
+     * j is the number of entries in the chain.
+     */
+
+    for (i = 0;  i < NUM_COUNTERS;  i++) {
+	count[i] = 0;
+    }
+    overflow = 0;
+    average = 0.0;
+    for (i = 0;  i < tablePtr->numBuckets;  i++) {
+	j = 0;
+	for (entryPtr = tablePtr->buckets[i];  entryPtr != NULL;
+	        entryPtr = entryPtr->nextPtr) {
+	    j++;
+	}
+	if (j < NUM_COUNTERS) {
+	    count[j]++;
+	} else {
+	    overflow++;
+	}
+	tmp = j;
+	average += (tmp+1.0)*(tmp/tablePtr->numEntries)/2.0;
+    }
+
+    /*
+     * Print out the histogram and a few other pieces of information.
+     */
+
+    result = (char *) ckalloc((unsigned) ((NUM_COUNTERS*60) + 300));
+    sprintf(result, "%d entries in table, %d buckets\n",
+	    tablePtr->numEntries, tablePtr->numBuckets);
+    p = result + strlen(result);
+    for (i = 0; i < NUM_COUNTERS; i++) {
+	sprintf(p, "number of buckets with %d entries: %d\n",
+		i, count[i]);
+	p += strlen(p);
+    }
+    sprintf(p, "number of buckets with %d or more entries: %d\n",
+	    NUM_COUNTERS, overflow);
+    p += strlen(p);
+    sprintf(p, "average search distance for entry: %.1f", average);
+    return result;
+}
+#endif /*TCL_COMPILE_STATS*/
+
+#ifdef TCL_COMPILE_DEBUG
+/*
+ *----------------------------------------------------------------------
+ *
+ * TclVerifyLocalLiteralTable --
+ *
+ *	Check a CompileEnv's local literal table for consistency.
+ *
+ * Results:
+ *	None.
+ *
+ * Side effects:
+ *	Panics if problems are found.
+ *
+ *----------------------------------------------------------------------
+ */
+
+void
+TclVerifyLocalLiteralTable(envPtr)
+    CompileEnv *envPtr;		/* Points to CompileEnv whose literal
+				 * table is to be validated. */
+{
+    register LiteralTable *localTablePtr = &(envPtr->localLitTable);
+    register LiteralEntry *localPtr;
+    char *bytes;
+    register int i;
+    int length, count;
+
+    count = 0;
+    for (i = 0;  i < localTablePtr->numBuckets;  i++) {
+	for (localPtr = localTablePtr->buckets[i];
+	        localPtr != NULL;  localPtr = localPtr->nextPtr) {
+	    count++;
+	    if (localPtr->refCount != -1) {
+		bytes = Tcl_GetStringFromObj(localPtr->objPtr, &length);
+		panic("TclVerifyLocalLiteralTable: local literal \"%.*s\" had bad refCount %d",
+		        (length>60? 60 : length), bytes,
+		        localPtr->refCount);
+	    }
+	    if (TclLookupLiteralEntry((Tcl_Interp *) envPtr->iPtr,
+		    localPtr->objPtr) == NULL) {
+		bytes = Tcl_GetStringFromObj(localPtr->objPtr, &length);
+		panic("TclVerifyLocalLiteralTable: local literal \"%.*s\" is not global",
+		         (length>60? 60 : length), bytes);
+	    }
+	    if (localPtr->objPtr->bytes == NULL) {
+		panic("TclVerifyLocalLiteralTable: literal has NULL string rep");
+	    }
+	}
+    }
+    if (count != localTablePtr->numEntries) {
+	panic("TclVerifyLocalLiteralTable: local literal table had %d entries, should be %d",
+	      count, localTablePtr->numEntries);
+    }
+}
+
+/*
+ *----------------------------------------------------------------------
+ *
+ * TclVerifyGlobalLiteralTable --
+ *
+ *	Check an interpreter's global literal table literal for consistency.
+ *
+ * Results:
+ *	None.
+ *
+ * Side effects:
+ *	Panics if problems are found.
+ *
+ *----------------------------------------------------------------------
+ */
+
+void
+TclVerifyGlobalLiteralTable(iPtr)
+    Interp *iPtr;		/* Points to interpreter whose global
+				 * literal table is to be validated. */
+{
+    register LiteralTable *globalTablePtr = &(iPtr->literalTable);
+    register LiteralEntry *globalPtr;
+    char *bytes;
+    register int i;
+    int length, count;
+
+    count = 0;
+    for (i = 0;  i < globalTablePtr->numBuckets;  i++) {
+	for (globalPtr = globalTablePtr->buckets[i];
+	        globalPtr != NULL;  globalPtr = globalPtr->nextPtr) {
+	    count++;
+	    if (globalPtr->refCount < 1) {
+		bytes = Tcl_GetStringFromObj(globalPtr->objPtr, &length);
+		panic("TclVerifyGlobalLiteralTable: global literal \"%.*s\" had bad refCount %d",
+		        (length>60? 60 : length), bytes,
+		        globalPtr->refCount);
+	    }
+	    if (globalPtr->objPtr->bytes == NULL) {
+		panic("TclVerifyGlobalLiteralTable: literal has NULL string rep");
+	    }
+	}
+    }
+    if (count != globalTablePtr->numEntries) {
+	panic("TclVerifyGlobalLiteralTable: global literal table had %d entries, should be %d",
+	      count, globalTablePtr->numEntries);
+    }
+}
+#endif /*TCL_COMPILE_DEBUG*/