Tcl Source Code

2011-05-17  Andreas Kupries  <[email protected]>

	* generic/tclCompile.c (TclFixupForwardJump): Tracked down and fixed
	* generic/tclBasic.c (TclArgumentBCEnter): the cause of a violation
	of my assertion that 'ePtr->nline == objc' in TclArgumentBCEnter.
	When a bytecode was grown during jump fixup the pc -> command line
	mapping was not updated. When things aligned just wrong the mapping
	would direct command A to the data for command B, with a different
	number of arguments.

2011-05-10  Don Porter  <[email protected]>

	* generic/tclInt.h:     New internal routines TclScanElement() and
	* generic/tclUtil.c:    TclConvertElement() are rewritten guts of
	machinery to produce string rep of lists.  The new routines avoid
	and correct [Bug 3173086].  See comments for much more detail.

	     * (1) ePtr->nline == objc
	     * (2) (ePtr->line[word] < 0) => !literal, for all words
	     * (3) (word == 0) => !literal
	     *
	     * Item (2) is why we can use objv to get the literals, and do not
	     * have to save them at compile time.
	     */

	    if (ePtr->nline != objc) {
		Tcl_Panic ("TIP 280 data structure inconsistency");
	    }

	    for (word = 1; word < objc; word++) {
		if (ePtr->line[word] >= 0) {
		    int isnew;
		    Tcl_HashEntry* hPtr =
			Tcl_CreateHashEntry (iPtr->lineLABCPtr,
					     (char*) objv[word], &isnew);

	    rangePtr->catchOffset += 3;
	    break;
	default:
	    Tcl_Panic("TclFixupForwardJump: bad ExceptionRange type %d",
		    rangePtr->type);
	}
    }

    /*
     * TIP #280: Adjust the mapping from PC values to the per-command
     * information about arguments and their line numbers.
     *
     * Note: We cannot simply remove an out-of-date entry and then reinsert
     * with the proper PC, because then we might overwrite another entry which
     * was at that location. Therefore we pull (copy + delete) all effected
     * entries (beyond the fixed PC) into an array, update them there, and at
     * last reinsert them all.
     */

    {
	ExtCmdLoc* eclPtr = envPtr->extCmdMapPtr;

	/* A helper structure */

	typedef struct {
	    int pc;
	    int cmd;
	} MAP;

	/*
	 * And the helper array. At most the whole hashtable is placed into
	 * this.
	 */

	MAP *map = (MAP*) ckalloc (sizeof(MAP) * eclPtr->litInfo.numEntries);

	Tcl_HashSearch hSearch;
	Tcl_HashEntry* hPtr;
	int n, k, isnew;

	/*
	 * Phase I: Locate the affected entries, and save them in adjusted
	 * form to the array. This removes them from the hash.
	 */

	for (n = 0, hPtr = Tcl_FirstHashEntry(&eclPtr->litInfo, &hSearch);
	     hPtr != NULL;
	     hPtr = Tcl_NextHashEntry(&hSearch)) {

	    map [n].cmd = PTR2INT(Tcl_GetHashValue(hPtr));
	    map [n].pc  = PTR2INT(Tcl_GetHashKey (&eclPtr->litInfo,hPtr));

	    if (map[n].pc >= (jumpFixupPtr->codeOffset + 2)) {
		Tcl_DeleteHashEntry(hPtr);
		map [n].pc += 3;
		n++;
	    }
	}

	/*
	 * Phase II: Re-insert the modified entries into the hash.
	 */

	for (k=0;k<n;k++) {
	    hPtr = Tcl_CreateHashEntry(&eclPtr->litInfo, INT2PTR(map[k].pc), &isnew);
	    Tcl_SetHashValue(hPtr, INT2PTR(map[k].cmd));
	}

	ckfree (map);
    }

    return 1;			/* the jump was grown */
}

/*
 *----------------------------------------------------------------------
 *
 * TclGetInstructionTable --