General Description: When I generate the 8x8 or 12x12 Speed Optimized Multiplier with "Verilog behavioral model" selected as the desired output, warnings similar to the following appear (the 12x12 multiplier warnings are shown here):
"WARNING: Core 12x12_Multiplier did not generate product VerilogSim. WARNING: Warnings and/or errors encountered while generating 12x12_Multiplier (12x12_Multiplier 1.0) All output products requested may not have been generated."
The warning is seen because Verilog behavioral models are not available for the M8x8 and M12x12 speed-optimized multipliers.
To work around this problem, perform a post-NGDBUILD Verilog functional simulation of the module. Please see (Xilinx Answer 8065) for more information on how to generate a post-NGDBUILD Verilog simulation netlist.