Prototype:

i32 @__nv_clzll(i64 %x) 

Description:

Count the number of consecutive leading zero bits, starting at the most significant bit (bit 63) of x.

Returns:

Returns a value between 0 and 64 inclusive representing the number of zero bits.

Library Availability:

Compute 2.0: Yes

Compute 3.0: Yes

Compute 3.5: Yes