vqadd

Vector Saturating Add

VQADD<c>.<dt> <Qd>, <Qn>, <Qm>

Adds elements with saturation.

Pseudocode Operation

for i = 0 to elements-1
  Qd[i] ← SatQ(Qn[i] + Qm[i], dt)

Example

VQADD.dt q0, q1, q2

Encoding

Binary Layout

1111001

31:25

U

24

0

23

D

22

size

21:20

Vn

19:16

Vd

15:12

0000

11:8

N

7

0

6

M

5

1

4

Vm

3:0

 

Format NEON 3-Reg

Opcode 0xF2000010

Extension NEON (SIMD)

Operands

• Qd
  Destination 128-bit SIMD register
• Qn
  First source 128-bit SIMD register
• Qm
  Second source 128-bit SIMD register

Related

More in NEON (SIMD)

Reference

View in Arm A64 ISA Reference ↗ Arm AArch32 ISA

Instruction Forms

Encoding	Instruction		ISA		Bit pattern
0xF2000010	VQADD{<c>}{<q>}.<dt> {<Dd>,} <Dn>, <Dm>		A32		1111001 | U | 0 | D | size | Vn | Vd | 0000 | N | 0 | M | 1 | Vm
0xF2000050	VQADD{<c>}{<q>}.<dt> {<Qd>,} <Qn>, <Qm>		A32		1111001 | U | 0 | D | size | Vn | Vd | 0000 | N | 1 | M | 1 | Vm
0xEF000010	VQADD{<c>}{<q>}.<dt> {<Dd>,} <Dn>, <Dm>		T32		111 | U | 11110 | D | size | Vn | Vd | 0000 | N | 0 | M | 1 | Vm
0xEF000050	VQADD{<c>}{<q>}.<dt> {<Qd>,} <Qn>, <Qm>		T32		111 | U | 11110 | D | size | Vn | Vd | 0000 | N | 1 | M | 1 | Vm

Description

Vector Saturating Add adds the values of corresponding elements of two vectors, and places the results in the destination vector. If any of the results overflow, they are saturated. The cumulative saturation bit, FPSCR.QC, is set if saturation occurs. For details see Pseudocode details of saturation. Depending on settings in the CPACR, NSACR, and HCPTR registers, and the Security state and PE mode in which the instruction is executed, an attempt to execute the instruction might be undefined, or trapped to Hyp mode. For more information see Enabling Advanced SIMD and floating-point support.

Operation

if ConditionPassed() then
    EncodingSpecificOperations();  CheckAdvSIMDEnabled();
    for r = 0 to regs-1
        for e = 0 to elements-1
            sum = Int(Elem[D[n+r],e,esize], unsigned) + Int(Elem[D[m+r],e,esize], unsigned);
            boolean sat;
            (Elem[D[d+r],e,esize], sat) = SatQ(sum, esize, unsigned);
            if sat then FPSCR.QC = '1';