UMAX (immediate)

Unsigned maximum with immediate (unpredicated)

Determine the unsigned maximum of an immediate and each element of the source vector, and destructively place the results in the corresponding elements of the source vector. The immediate is an unsigned 8-bit value in the range 0 to 255, inclusive. This instruction is unpredicated.

313029282726252423222120191817161514131211109876543210
00100101size101001110imm8Zdn
U

UMAX <Zdn>.<T>, <Zdn>.<T>, #<imm>

if !HaveSVE() && !HaveSME() then UNDEFINED; constant integer esize = 8 << UInt(size); integer dn = UInt(Zdn); boolean unsigned = TRUE; integer imm = Int(imm8, unsigned);

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 B
01 H
10 S
11 D
<imm>

Is the unsigned immediate operand, in the range 0 to 255, encoded in the "imm8" field.

Operation

CheckSVEEnabled(); constant integer VL = CurrentVL; constant integer elements = VL DIV esize; bits(VL) operand1 = Z[dn, VL]; bits(VL) result; for e = 0 to elements-1 integer element1 = Int(Elem[operand1, e, esize], unsigned); Elem[result, e, esize] = Max(element1, imm)<esize-1:0>; Z[dn, VL] = result;

Operational information

If FEAT_SVE2 is implemented or FEAT_SME is implemented, then if PSTATE.DIT is 1:

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:


Internal version only: aarchmrs v2023-12_rel, pseudocode v2023-12_rel, sve v2023-12_rel ; Build timestamp: 2023-12-15T16:46

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