3.180. __nv_ilogb

Prototype: 

i32 @__nv_ilogb(double %x)

Description:

Calculates the unbiased integer exponent of the input argument x.

Returns:

  • If successful, returns the unbiased exponent of the argument.

  • __nv_ilogb(0) returns INT_MIN.

  • __nv_ilogb(NaN) returns INT_MIN.

  • __nv_ilogb(x) returns INT_MAX if x is ∞ or the correct value is greater than INT_MAX.

  • __nv_ilogb(x) return INT_MIN if the correct value is less than INT_MIN.

Note:

For accuracy information see the CUDA C++ Programming Guide, Mathematical Functions Appendix, Double-Precision Floating-Point Functions section.

Library Availability:

Compute 2.0: Yes

Compute 3.0: Yes

Compute 3.5: Yes