Base Instructions | SIMD&FP Instructions | SVE Instructions | SME Instructions | Index by Encoding | Shared Pseudocode | Proprietary Notice

## FADD (immediate)

Floating-point add immediate (predicated)

Add an immediate to each active floating-point element of the source vector, and destructively place the results in the corresponding elements of the source vector. The immediate may take the value +0.5 or +1.0 only. Inactive elements in the destination vector register remain unmodified.

31 | 30 | 29 | 28 | 27 | 26 | 25 | 24 | 23 | 22 | 21 | 20 | 19 | 18 | 17 | 16 | 15 | 14 | 13 | 12 | 11 | 10 | 9 | 8 | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0
0 | 1 | 1 | 0 | 0 | 1 | 0 | 1 | size | 0 | 1 | 1 | 0 | 0 | 0 | 1 | 0 | 0 | Pg | 0 | 0 | 0 | 0 | i1 | Zdn

####

FADD <Zdn>.<T>, <Pg>/M, <Zdn>.<T>, <const>

if !HaveSVE() && !HaveSME() then UNDEFINED; if size == '00' then UNDEFINED; constant integer esize = 8 << UInt(size); integer g = UInt(Pg); integer dn = UInt(Zdn); bits(esize) imm = if i1 == '0' then FPPointFive('0', esize) else FPOne('0', esize);

### Assembler Symbols

<Zdn> | Is the name of the source and destination scalable vector register, encoded in the "Zdn" field.

<T> | Is the size specifier, encoded in size:
size | <T>
--- | ---
00 | RESERVED
01 | H
10 | S
11 | D

<Pg> | Is the name of the governing scalable predicate register P0-P7, encoded in the "Pg" field.

<const> | Is the floating-point immediate value, encoded in i1:
i1 | <const>
--- | ---
0 | #0.5
1 | #1.0

### Operation

CheckSVEEnabled(); constant integer VL = CurrentVL; constant integer PL = VL DIV 8; constant integer elements = VL DIV esize; bits(PL) mask = P[g, PL]; bits(VL) operand1 = Z[dn, VL]; bits(VL) result; for e = 0 to elements-1 bits(esize) element1 = Elem[operand1, e, esize]; if ActivePredicateElement(mask, e, esize) then Elem[result, e, esize] = FPAdd(element1, imm, FPCR[]); else Elem[result, e, esize] = element1; Z[dn, VL] = result;

### Operational information

This instruction might be immediately preceded in program order by a MOVPRFX instruction. The MOVPRFX instruction must conform to all of the following requirements, otherwise the behavior of the MOVPRFX and this instruction is unpredictable:

- The MOVPRFX instruction must be unpredicated, or be predicated using the same governing predicate register and source element size as this instruction.
- The MOVPRFX instruction must specify the same destination register as this instruction.
- The destination register must not refer to architectural register state referenced by any other source operand register of this instruction.

Base Instructions | SIMD&FP Instructions | SVE Instructions | SME Instructions | Index by Encoding | Shared Pseudocode | Proprietary Notice

Internal version only: isa v33.64, AdvSIMD v29.12, pseudocode v2023-06_rel, sve v2023-06_rel ; Build timestamp: 2023-07-04T19:42

Copyright © 2010-2023 Arm Limited or its affiliates. All rights reserved. This document is Non-Confidential.