BEXT - RISC-V instruction reference

bextExtract bit 
Sets t1 to the value, 0 or 1, of the bit of t2 whose index is in the low bits of t3.
RISC-V manual: bext 
Forms  bext , ,   
Operands t1 Any integer register, x0 to x31, or its named alias, such as zero, t0 or t6. 
t2 An integer register. It may be the same register as t1. 
t3 An integer register. It may be the same register as t1. 
 .text
li t0, 13
li t1, 2
# t0=13, t1=2; bext writes 1 to t2.
bext t2, t0, t1