The shift
method also supports an enabled input, allowing the shift process to be controlled and enabled by a variable.
// Include the Class
#include "ap_shift_reg.h"
// Define a variable of type ap_shift_reg<type, depth>
// - Sreg must use the static qualifier
// - Sreg will hold integer data types
// - Sreg will hold 4 data values
static ap_shift_reg<int, 4> Sreg;
int var1, In1;
bool En;
// Read location 3 of Sreg into var1
// THEN if En=1
// Shift all values up one and load In1 into location 0
var1 = Sreg.shift(In1,3,En);
When using the ap_shift_reg
class, Vitis HLS creates a unique RTL component for
each shifter. When logic synthesis is performed, this component is synthesized into
an SRL resource.