System and method for register renaming

A method for performing register renaming of source registers in a processor having a variable advance instruction window for storing a group of instructions to be executed by the processor, wherein new instructions are added to the variable advance instruction window when a location becomes available therein, the method comprising the steps of:

• (a) storing source and destination register addresses for the instructions in the variable advance instruction window;
• (b) assigning a tag to each instruction in the variable advance instruction window, wherein the tag of each retired instruction is assigned to the next new instruction to be added to the variable advance instruction window;
• (c) storing, in a temp buffer, results of instructions executed by the processor according to their corresponding tags to avoid output and anti-dependencies, said temp buffer permitting the processor to execute instructions out of order and in parallel;
• (d) performing data dependency checks for input dependencies for each new instruction added to the variable advance instruction window;
• (e) determining where operands are located in the temp buffer for the instructions having input dependencies as determined by step (d);
• (f) renaming source register addresses of the instructions having dependencies;
• and
• (g) storing said renamed source register addresses in a rename result register file.