OpenGL Programming Guide: The Official Guide to Learning OpenGL, Version 4.3, Eighth Edition

Integer Functions

For these functions, the notation [a, b] means the set of bits from bit-number a through bit-number b, inclusive. The lowest-order bit is bit 0. “Bit number” will always refer to counting up from the lowest-order bit as bit 0.

genUType uaddCarry(genUType x, genUType y,                         out genUType carry);

Adds 32-bit unsigned integer x and y, returning the sum modulo 2³². The value carry is set to 0 if the sum was less than 2³², or to 1 otherwise.

genUType usubBorrow(genUType x, genUType y,                         out genUType borrow);

Subtracts the 32-bit unsigned integer y from x, returning the difference if nonnegative, or 2³² plus the difference otherwise. The value borrow is set to 0 if x ≥ y, or to 1 otherwise. ...