3.118. __nv_ffsll

Prototype:

i32 @__nv_ffsll(i64 %x) 

Description:

Find the position of the first (least significant) bit set to 1 in x, where the least significant bit position is 1.

Returns:

Returns a value between 0 and 64 inclusive representing the position of the first bit set.
  • __nv_ffsll(0) returns 0.

Library Availability:

Compute 2.0: Yes

Compute 3.0: Yes

Compute 3.5: Yes