fre.

Reciprocal Estimate

fre. RT,RA

Estimates the reciprocal of a floating-point number.

Details

The fre. instruction estimates the reciprocal of the contents of register RA and places the result into register RT.

Pseudocode Operation

if 'fre.' then
    RT <- estimate_reciprocal(RA)

Programming Note

The fre. instruction provides a fast, approximate reciprocal value, useful for performance-critical applications like graphics or scientific computing where precision can be traded for speed. Ensure that the input register RA contains a non-zero value to avoid undefined behavior; otherwise, consider adding checks to handle zero inputs gracefully.

Example

fre. r3, r4

Encoding

Binary Layout
18
0
LI
6
AA
30
LK
31
 
Format XO-form
Opcode 0xFC000031
Extension Floating-Point

Operands

  • RT
    Target Floating-Point Register
  • RA
    Source Floating-Point Register