why do we use barrel shifter

[fahum]

why do we use barrel shifter when we can simply shift the data using wire shift ? like this in VHDL :

B <= A(31 downto 0 ) & Zeros (31 downto 0) ;

 

[barry]

I'm assuming your code is trying to shift a 32-bit word left 32 bits into a 64-bit word, right?

A barrel shifter is a PHYSICAL realization IMPLIED by your VHDL code.

 

[dll_fpga]

I'm assuming your code is trying to shift a 32-bit word left 32 bits into a 64-bit word, right?

A barrel shifter is a PHYSICAL realization IMPLIED by your VHDL code.

barrel shifter is nothing but cascaded mux whose select can be controlled for almost any sort of shifts