tclcompile.c

tcl是工具命令语言

    
    p = (unsigned char *) ckalloc((size_t) structureSize);
    codePtr = (ByteCode *) p;
    codePtr->interpHandle = TclHandlePreserve(iPtr->handle);
    codePtr->compileEpoch = iPtr->compileEpoch;
    codePtr->nsPtr = namespacePtr;
    codePtr->nsEpoch = namespacePtr->resolverEpoch;
    codePtr->refCount = 1;
    codePtr->flags = 0;
    codePtr->source = envPtr->source;
    codePtr->procPtr = envPtr->procPtr;

    codePtr->numCommands = envPtr->numCommands;
    codePtr->numSrcBytes = envPtr->numSrcBytes;
    codePtr->numCodeBytes = codeBytes;
    codePtr->numLitObjects = numLitObjects;
    codePtr->numExceptRanges = envPtr->exceptArrayNext;
    codePtr->numAuxDataItems = envPtr->auxDataArrayNext;
    codePtr->numCmdLocBytes = cmdLocBytes;
    codePtr->maxExceptDepth = envPtr->maxExceptDepth;
    codePtr->maxStackDepth = envPtr->maxStackDepth;

    p += sizeof(ByteCode);
    codePtr->codeStart = p;
    memcpy((VOID *) p, (VOID *) envPtr->codeStart, (size_t) codeBytes);
    
    p += TCL_ALIGN(codeBytes);	      /* align object array */
    codePtr->objArrayPtr = (Tcl_Obj **) p;
    for (i = 0;  i < numLitObjects;  i++) {
	codePtr->objArrayPtr[i] = envPtr->literalArrayPtr[i].objPtr;
    }

    p += TCL_ALIGN(objArrayBytes);    /* align exception range array */
    if (exceptArrayBytes > 0) {
	codePtr->exceptArrayPtr = (ExceptionRange *) p;
	memcpy((VOID *) p, (VOID *) envPtr->exceptArrayPtr,
	        (size_t) exceptArrayBytes);
    } else {
	codePtr->exceptArrayPtr = NULL;
    }
    
    p += TCL_ALIGN(exceptArrayBytes); /* align AuxData array */
    if (auxDataArrayBytes > 0) {
	codePtr->auxDataArrayPtr = (AuxData *) p;
	memcpy((VOID *) p, (VOID *) envPtr->auxDataArrayPtr,
	        (size_t) auxDataArrayBytes);
    } else {
	codePtr->auxDataArrayPtr = NULL;
    }

    p += auxDataArrayBytes;
    nextPtr = EncodeCmdLocMap(envPtr, codePtr, (unsigned char *) p);
#ifdef TCL_COMPILE_DEBUG
    if (((size_t)(nextPtr - p)) != cmdLocBytes) {	
	panic("TclInitByteCodeObj: encoded cmd location bytes %d != expected size %d\n", (nextPtr - p), cmdLocBytes);
    }
#endif
    
    /*
     * Record various compilation-related statistics about the new ByteCode
     * structure. Don't include overhead for statistics-related fields.
     */

#ifdef TCL_COMPILE_STATS
    codePtr->structureSize = structureSize
	    - (sizeof(size_t) + sizeof(Tcl_Time));
    Tcl_GetTime(&(codePtr->createTime));
    
    RecordByteCodeStats(codePtr);
#endif /* TCL_COMPILE_STATS */
    
    /*
     * Free the old internal rep then convert the object to a
     * bytecode object by making its internal rep point to the just
     * compiled ByteCode.
     */
	    
    if ((objPtr->typePtr != NULL) &&
	    (objPtr->typePtr->freeIntRepProc != NULL)) {
	(*objPtr->typePtr->freeIntRepProc)(objPtr);
    }
    objPtr->internalRep.otherValuePtr = (VOID *) codePtr;
    objPtr->typePtr = &tclByteCodeType;
}

/*
 *----------------------------------------------------------------------
 *
 * LogCompilationInfo --
 *
 *	This procedure is invoked after an error occurs during compilation.
 *	It adds information to the "errorInfo" variable to describe the
 *	command that was being compiled when the error occurred.
 *
 * Results:
 *	None.
 *
 * Side effects:
 *	Information about the command is added to errorInfo and the
 *	line number stored internally in the interpreter is set.  If this
 *	is the first call to this procedure or Tcl_AddObjErrorInfo since
 *	an error occurred, then old information in errorInfo is
 *	deleted.
 *
 *----------------------------------------------------------------------
 */

static void
LogCompilationInfo(interp, script, command, length)
    Tcl_Interp *interp;		/* Interpreter in which to log the
				 * information. */
    CONST char *script;		/* First character in script containing
				 * command (must be <= command). */
    CONST char *command;	/* First character in command that
				 * generated the error. */
    int length;			/* Number of bytes in command (-1 means
				 * use all bytes up to first null byte). */
{
    char buffer[200];
    register CONST char *p;
    char *ellipsis = "";
    Interp *iPtr = (Interp *) interp;

    if (iPtr->flags & ERR_ALREADY_LOGGED) {
	/*
	 * Someone else has already logged error information for this
	 * command; we shouldn't add anything more.
	 */

	return;
    }

    /*
     * Compute the line number where the error occurred.
     */

    iPtr->errorLine = 1;
    for (p = script; p != command; p++) {
	if (*p == '\n') {
	    iPtr->errorLine++;
	}
    }

    /*
     * Create an error message to add to errorInfo, including up to a
     * maximum number of characters of the command.
     */

    if (length < 0) {
	length = strlen(command);
    }
    if (length > 150) {
	length = 150;
	ellipsis = "...";
    }
    sprintf(buffer, "\n    while compiling\n\"%.*s%s\"",
	    length, command, ellipsis);
    Tcl_AddObjErrorInfo(interp, buffer, -1);
}

/*
 *----------------------------------------------------------------------
 *
 * TclFindCompiledLocal --
 *
 *	This procedure is called at compile time to look up and optionally
 *	allocate an entry ("slot") for a variable in a procedure's array of
 *	local variables. If the variable's name is NULL, a new temporary
 *	variable is always created. (Such temporary variables can only be
 *	referenced using their slot index.)
 *
 * Results:
 *	If create is 0 and the name is non-NULL, then if the variable is
 *	found, the index of its entry in the procedure's array of local
 *	variables is returned; otherwise -1 is returned. If name is NULL,
 *	the index of a new temporary variable is returned. Finally, if
 *	create is 1 and name is non-NULL, the index of a new entry is
 *	returned.
 *
 * Side effects:
 *	Creates and registers a new local variable if create is 1 and
 *	the variable is unknown, or if the name is NULL.
 *
 *----------------------------------------------------------------------
 */

int
TclFindCompiledLocal(name, nameBytes, create, flags, procPtr)
    register CONST char *name;	/* Points to first character of the name of
				 * a scalar or array variable. If NULL, a
				 * temporary var should be created. */
    int nameBytes;		/* Number of bytes in the name. */
    int create;			/* If 1, allocate a local frame entry for
				 * the variable if it is new. */
    int flags;			/* Flag bits for the compiled local if
				 * created. Only VAR_SCALAR, VAR_ARRAY, and
				 * VAR_LINK make sense. */
    register Proc *procPtr;	/* Points to structure describing procedure
				 * containing the variable reference. */
{
    register CompiledLocal *localPtr;
    int localVar = -1;
    register int i;

    /*
     * If not creating a temporary, does a local variable of the specified
     * name already exist?
     */

    if (name != NULL) {	
	int localCt = procPtr->numCompiledLocals;
	localPtr = procPtr->firstLocalPtr;
	for (i = 0;  i < localCt;  i++) {
	    if (!TclIsVarTemporary(localPtr)) {
		char *localName = localPtr->name;
		if ((nameBytes == localPtr->nameLength)
	                && (strncmp(name, localName, (unsigned) nameBytes) == 0)) {
		    return i;
		}
	    }
	    localPtr = localPtr->nextPtr;
	}
    }

    /*
     * Create a new variable if appropriate.
     */
    
    if (create || (name == NULL)) {
	localVar = procPtr->numCompiledLocals;
	localPtr = (CompiledLocal *) ckalloc((unsigned) 
	        (sizeof(CompiledLocal) - sizeof(localPtr->name)
		+ nameBytes+1));
	if (procPtr->firstLocalPtr == NULL) {
	    procPtr->firstLocalPtr = procPtr->lastLocalPtr = localPtr;
	} else {
	    procPtr->lastLocalPtr->nextPtr = localPtr;
	    procPtr->lastLocalPtr = localPtr;
	}
	localPtr->nextPtr = NULL;
	localPtr->nameLength = nameBytes;
	localPtr->frameIndex = localVar;
	localPtr->flags = flags | VAR_UNDEFINED;
	if (name == NULL) {
	    localPtr->flags |= VAR_TEMPORARY;
	}
	localPtr->defValuePtr = NULL;
	localPtr->resolveInfo = NULL;

	if (name != NULL) {
	    memcpy((VOID *) localPtr->name, (VOID *) name,
	            (size_t) nameBytes);
	}
	localPtr->name[nameBytes] = '\0';
	procPtr->numCompiledLocals++;
    }
    return localVar;
}

/*
 *----------------------------------------------------------------------
 *
 * TclInitCompiledLocals --
 *
 *	This routine is invoked in order to initialize the compiled
 *	locals table for a new call frame.
 *
 * Results:
 *	None.
 *
 * Side effects:
 *	May invoke various name resolvers in order to determine which
 *	variables are being referenced at runtime.
 *
 *----------------------------------------------------------------------
 */

void
TclInitCompiledLocals(interp, framePtr, nsPtr)
    Tcl_Interp *interp;		/* Current interpreter. */
    CallFrame *framePtr;	/* Call frame to initialize. */
    Namespace *nsPtr;		/* Pointer to current namespace. */
{
    register CompiledLocal *localPtr;
    Interp *iPtr = (Interp*) interp;
    Tcl_ResolvedVarInfo *vinfo, *resVarInfo;
    Var *varPtr = framePtr->compiledLocals;
    Var *resolvedVarPtr;
    ResolverScheme *resPtr;
    int result;

    /*
     * Initialize the array of local variables stored in the call frame.
     * Some variables may have special resolution rules.  In that case,
     * we call their "resolver" procs to get our hands on the variable,
     * and we make the compiled local a link to the real variable.
     */

    for (localPtr = framePtr->procPtr->firstLocalPtr;
	 localPtr != NULL;
	 localPtr = localPtr->nextPtr) {

	/*
	 * Check to see if this local is affected by namespace or
	 * interp resolvers.  The resolver to use is cached for the
	 * next invocation of the procedure.
	 */

	if (!(localPtr->flags & (VAR_ARGUMENT|VAR_TEMPORARY|VAR_RESOLVED))
		&& (nsPtr->compiledVarResProc || iPtr->resolverPtr)) {
	    resPtr = iPtr->resolverPtr;

	    if (nsPtr->compiledVarResProc) {
		result = (*nsPtr->compiledVarResProc)(nsPtr->interp,
			localPtr->name, localPtr->nameLength,
			(Tcl_Namespace *) nsPtr, &vinfo);
	    } else {
		result = TCL_CONTINUE;
	    }

	    while ((result == TCL_CONTINUE) && resPtr) {
		if (resPtr->compiledVarResProc) {
		    result = (*resPtr->compiledVarResProc)(nsPtr->interp,
			    localPtr->name, localPtr->nameLength,
			    (Tcl_Namespace *) nsPtr, &vinfo);
		}
		resPtr = resPtr->nextPtr;
	    }
	    if (result == TCL_OK) {
		localPtr->resolveInfo = vinfo;
		localPtr->flags |= VAR_RESOLVED;
	    }
	}

	/*
	 * Now invoke the resolvers to determine the exact variables that
	 * should be used.
	 */

        resVarInfo = localPtr->resolveInfo;
        resolvedVarPtr = NULL;

        if (resVarInfo && resVarInfo->fetchProc) {
            resolvedVarPtr = (Var*) (*resVarInfo->fetchProc)(interp,
		    resVarInfo);
        }

        if (resolvedVarPtr) {
	    varPtr->name = localPtr->name; /* will be just '\0' if temp var */
	    varPtr->nsPtr = NULL;
	    varPtr->hPtr = NULL;
	    varPtr->refCount = 0;
	    varPtr->tracePtr = NULL;
	    varPtr->searchPtr = NULL;
	    varPtr->flags = 0;
            TclSetVarLink(varPtr);
            varPtr->value.linkPtr = resolvedVarPtr;
            resolvedVarPtr->refCount++;
        } else {
	    varPtr->value.objPtr = NULL;
	    varPtr->name = localPtr->name; /* will be just '\0' if temp var */
	    varPtr->nsPtr = NULL;
	    varPtr->hPtr = NULL;
	    varPtr->refCount = 0;
	    varPtr->tracePtr = NULL;
	    varPtr->searchPtr = NULL;
	    varPtr->flags = localPtr->flags;
        }
	varPtr++;
    }
}

/*
 *----------------------------------------------------------------------
 *
 * TclExpandCodeArray --
 *
 *	Procedure that uses malloc to allocate more storage for a
 *	CompileEnv's code array.
 *
 * Results:
 *	None. 
 *
 * Side effects:
 *	The byte code array in *envPtr is reallocated to a new array of
 *	double the size, and if envPtr->mallocedCodeArray is non-zero the
 *	old array is freed. Byte codes are copied from the old array to the
 *	new one.
 *
 *----------------------------------------------------------------------
 */