uminv

SVE Unsigned Minimum Reduction

UMINV <Vd>, <Pg>, <Zn>.<T>

Finds min unsigned element in vector.

Pseudocode Operation

bits(esize) result = ALL_ONES(esize);
for i = 0 to VL/esize - 1
  if Pg[i] == '1' then
    element = Zn[i*esize +: esize];
    if element < result (unsigned) then result = element;
Vd[0 +: esize] ← result;

Example

UMINV v0.4s, p0/m, z1.s.T

Encoding

Binary Layout

00000100

31:24

size

23:22

0010

21:18

1

17

1

16

001

15:13

Pg

12:10

Zn

9:5

Vd

4:0

 

Format SVE Reduction

Opcode 0x040B2000

Extension SVE

Operands

• Vd
  Dest Scalar
• Pg
  Mask
• Zn
  Vector

Related

Other forms of uminv

• uminv Vector Unsigned Minimum Across

More in SVE

Reference

View in Arm A64 ISA Reference ↗ Arm A64 ISA

Instruction Forms

Encoding	Instruction		ISA		Bit pattern
0x2E31A800	UMINV <V><d>, <Vn>.<T>		A64		0 | Q | 1 | 01110 | size | 11000 | 1 | 101010 | Rn | Rd
0x040B2000	UMINV <V><d>, <Pg>, <Zn>.<T>		A64		00000100 | size | 0010 | 1 | 1 | 001 | Pg | Zn | Vd

Description

Unsigned minimum horizontally across all lanes of a vector, and place the result in the SIMD&FP scalar destination register. Inactive elements in the source vector are treated as the maximum unsigned integer for the element size.

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) operand = if AnyActiveElement(mask, esize) then Z[n, VL] else Zeros(VL);
integer minimum = if unsigned then (2^esize - 1) else (2^(esize-1) - 1);

for e = 0 to elements-1
    if ActivePredicateElement(mask, e, esize) then
        integer element = Int(Elem[operand, e, esize], unsigned);
        minimum = Min(minimum, element);

V[d, esize] = minimum<esize-1:0>;