5.7.2. FADD and FSUB

Floating-point add and subtract.

FADD and FSUB can be scalar, vector, or mixed (see Vector and scalar operations).

Syntax

FADD<precision>{cond} Fd, Fn, Fm
FSUB<precision>{cond} Fd, Fn, Fm

where:

<precision>

must be either S for single-precision, or D for double-precision.

cond

is an optional condition code (see VFP and condition codes).

Fd

is the VFP register for the result.

Fn

is the VFP register holding the first operand.

Fm

is the VFP register holding the second operand.

The precision of Fd, Fn and Fm must match the precision specified in <precision>.

Usage

The FADD instruction adds the values in Fn and Fm and places the result in Fd.

The FSUB instruction subtracts the value in Fm from the value in Fn and places the result in Fd.

Exceptions

FADD and FSUB instructions can produce Invalid Operation, Overflow, or Inexact exceptions.

Examples

    FSUBSEQ     s2, s4, s17
    FADDDGT     d4, d0, d12
    FSUBD       d0, d0, d12
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