EON

Bitwise exclusive OR with inverted immediate (unpredicated)

Bitwise exclusive OR an inverted immediate with each 64-bit element of the source vector, and destructively place the results in the corresponding elements of the source vector. The immediate is a 64-bit value consisting of a single run of ones or zeros repeating every 2, 4, 8, 16, 32 or 64 bits. This instruction is unpredicated.

This is a pseudo-instruction of EOR (immediate). This means:

313029282726252423222120191817161514131211109876543210
00000101010000imm13Zdn

EON <Zdn>.<T>, <Zdn>.<T>, #<const>

is equivalent to

EOR <Zdn>.<T>, <Zdn>.<T>, #(-<const> - 1)

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 imm13<12>:imm13<5:0>:

imm13<12> imm13<5:0> <T>
0 0xxxxx S
0 10xxxx H
0 110xxx B
0 1110xx B
0 11110x B
0 111110 RESERVED
0 111111 RESERVED
1 xxxxxx D
<const>

Is a 64, 32, 16 or 8-bit bitmask consisting of replicated 2, 4, 8, 16, 32 or 64 bit fields, each field containing a rotated run of non-zero bits, encoded in the "imm13" field.

Operation

The description of EOR (immediate) gives the operational pseudocode for this instruction.

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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