Actually there is ONLY one program to convert from MATLAB LANGUAGE to VHDL and is ACCELCHIP.
But even in ACCELCHIP don't expect to convert evry single function of MATLAB to VHDL ..What happens is that MATLAB has internal functions that for speed sake are not IN MATLAB language .So there is no MATLAB SOURCE avalaible .
But if you what to do SIGNAL PROCESSING ..well then you can use SIMULINK, and there are a lot of OPTIONS now, that PRODUCE VHDL output from DSP blocksets from all the main DSP/FPGA technology SUPPLIERS !!!!