//MACRO     Avl.find  Anchor, Node, Key, CompMacro, NullLbl, WReg[], FieldDispl= 0
//--------------------------------------------------------------------------------------------------
//
//  @ CopyRight Roberti & Parau Enterprises, Inc.  2021-2023
//
//  This work is licensed under the Creative Commons Attribution-NoDerivatives 4.0 International License.
//  To view a copy of this license, visit http://creativecommons.org/licenses/by-nd/4.0/
//   or send a letter to Creative Commons, PO Box 1866, Mountain View, CA 94042, USA.
//
//--------------------------------------------------------------------------------------------------
//
    //
    //  Get load/store MIs and word length
    //
    eval(DVASM.getEnv()[4]);
    var ld= "L" + abiWID;
    var st= "S" + abiWID;
    var wl= abiWLen;

    var goRight= DVASM.getNewLabel();
    var matchLbl= DVASM.getNewLabel();
    var leftField= FieldDispl;
    var rightField= wl*2 + "+" + FieldDispl;
    
    if (WReg.length < 1)
    	return DVASM.putError("Number of working registers for macro [AVL.FIND] is " + WReg.length + 
    	" bu it must be at lease 1")
    
    //
    //  Set up registers and addresses
    //  
    var pFld= WReg[0];
    var next= WReg[0];
    
    //
    //  Generate code
    //
\#Label     #ld         #Node, #Anchor                    	// Load root node addr
\           IF          ( #Node == 0 ), GOTO, ID= #NullLbl	// Check if tree is empty
\			DO
\               #CompMacro  #Key, #Node, #goRight, #matchLbl, [#WReg]	// Compare keys
\				#ld			#Node, #leftField[#Node]			// Search left subtree
\				IF 			( #Node != 0 ), CONTINUE			// CHeck new node if it exists
\				GOTO		#NullLbl							// Done otherwise
\#goRight		#ld			#Node, #rightField[#Node]			// Search right subtree
\				IF 			( #Node != 0 ), CONTINUE			// CHeck new node if it exists
\				GOTO		#NullLbl							// Done otherwise
\				ENDDO
\#matchLbl	BYTE	0[0]