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

## URSHL (multiple and single vector)

Multi-vector unsigned rounding shift left by vector

Shift the unsigned elements of the two or four first source vectors by corresponding elements of the second source vector and destructively place the rounded results in the corresponding elements of the two or four first source vectors. A positive shift amount performs a left shift, otherwise a right shift by the negated shift amount is performed.

This instruction is unpredicated.

It has encodings from 2 classes: Two registers and Four registers

### Two registers
(FEAT_SME2)

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
1 | 1 | 0 | 0 | 0 | 0 | 0 | 1 | size | 1 | 0 | Zm | 1 | 0 | 1 | 0 | 0 | 0 | 1 | 0 | 0 | 0 | 1 | Zdn | 1
|  |  |  |  |  |  |  |  | U

####

URSHL { <Zdn1>.<T>-<Zdn2>.<T> }, { <Zdn1>.<T>-<Zdn2>.<T> }, <Zm>.<T>

if !IsFeatureImplemented(FEAT_SME2) then UNDEFINED; constant integer esize = 8 << UInt(size); constant integer dn = UInt(Zdn:'0'); constant integer m = UInt('0':Zm); constant integer nreg = 2;

### Four registers
(FEAT_SME2)

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
1 | 1 | 0 | 0 | 0 | 0 | 0 | 1 | size | 1 | 0 | Zm | 1 | 0 | 1 | 0 | 1 | 0 | 1 | 0 | 0 | 0 | 1 | Zdn | 0 | 1
|  |  |  |  |  |  |  |  |  | U

####

URSHL { <Zdn1>.<T>-<Zdn4>.<T> }, { <Zdn1>.<T>-<Zdn4>.<T> }, <Zm>.<T>

if !IsFeatureImplemented(FEAT_SME2) then UNDEFINED; constant integer esize = 8 << UInt(size); constant integer dn = UInt(Zdn:'00'); constant integer m = UInt('0':Zm); constant integer nreg = 4;

### Assembler Symbols

<Zdn1> | For the two registers variant: is the name of the first scalable vector register of the destination and first source multi-vector group, encoded as "Zdn" times 2.
| For the four registers variant: is the name of the first scalable vector register of the destination and first source multi-vector group, encoded as "Zdn" times 4.

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

<Zdn4> | Is the name of the fourth scalable vector register of the destination and first source multi-vector group, encoded as "Zdn" times 4 plus 3.

<Zdn2> | Is the name of the second scalable vector register of the destination and first source multi-vector group, encoded as "Zdn" times 2 plus 1.

<Zm> | Is the name of the second source scalable vector register Z0-Z15, encoded in the "Zm" field.

### Operation

CheckStreamingSVEEnabled(); constant integer VL = CurrentVL; constant integer elements = VL DIV esize; array [0..3] of bits(VL) results; for r = 0 to nreg-1 constant bits(VL) operand1 = Z[dn+r, VL]; constant bits(VL) operand2 = Z[m, VL]; for e = 0 to elements-1 constant integer element = UInt(Elem[operand1, e, esize]); integer shift = ShiftSat(SInt(Elem[operand2, e, esize]), esize); integer res; if shift >= 0 then res = element << shift; else shift = -shift; res = (element + (1 << (shift - 1))) >> shift; Elem[results[r], e, esize] = res<esize-1:0>; for r = 0 to nreg-1 Z[dn+r, VL] = results[r];

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

Internal version only: aarchmrs v2024-03_relA, pseudocode v2024-03_rel, sve v2024-03_rel ; Build timestamp: 2024-03-26T09:45

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