libdevice User's Guide (PDF) - CUDA Toolkit v5.5 (older) - Last updated May 11, 2013 - Send Feedback

3.119. __nv_ffs

Prototype:

i32 @__nv_ffs(i32 %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 32 inclusive representing the position of the first bit set.
  • __nv_ffs(0) returns 0.

Library Availability:

Compute 2.0: Yes

Compute 3.0: Yes

Compute 3.5: Yes


libdevice User's Guide (PDF) - CUDA Toolkit v5.5 (older) - Last updated May 11, 2013 - Send Feedback