-Have to use multiplication instructions in the program code.
-There must be at least 20 I/O ports
-At least 5 MIPS
-Will work under high temperature and vibration
I used to use PIC, but this time I need a faster one with MUL instructions.
Waiting for any answer or suggestion.
If you are used to work with PICs I think the most suitable micro for you would be a dsPIC. This device is a hybrid between a conventional microcontroller and a DSP. It is actually a 16-bit micro with a DSP engine, so it will fit quite nicely in your requirements.
As you are used to PICs, you'll find it easy to understand.
In the other hand, if you don't mind learning new architecture, i would suggest the MSP430 family from Texas Instruments. These are more efficient and cheaper than the Microchip's ones.
I encourage you to take a look at their datasheet in TI's website: https://www.ti.com