Signed saturating Shift Left Unsigned (immediate). This instruction reads each signed integer value in the vector of the source SIMD&FP register, shifts each value by an immediate value, saturates the shifted result to an unsigned integer value, places the result in a vector, and writes the vector to the destination SIMD&FP register. The results are truncated. For rounded results, see UQRSHL.
If saturation occurs, the cumulative saturation bit FPSR.QC is set.
Depending on the settings in the CPACR_EL1, CPTR_EL2, and CPTR_EL3 registers, and the current Security state and Exception level, an attempt to execute the instruction might be trapped.
It has encodings from 2 classes: Scalar and Vector
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0 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 0 | != 0000 | immb | 0 | 1 | 1 | 0 | 0 | 1 | Rn | Rd | |||||||||||||
U | immh | op |
integer d = UInt(Rd); integer n = UInt(Rn); if immh == '0000' then UNDEFINED; integer esize = 8 << HighestSetBit(immh); integer datasize = esize; integer elements = 1; integer shift = UInt(immh:immb) - esize; boolean src_unsigned; boolean dst_unsigned; case op:U of when '00' UNDEFINED; when '01' src_unsigned = FALSE; dst_unsigned = TRUE; when '10' src_unsigned = FALSE; dst_unsigned = FALSE; when '11' src_unsigned = TRUE; dst_unsigned = TRUE;
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0 | Q | 1 | 0 | 1 | 1 | 1 | 1 | 0 | != 0000 | immb | 0 | 1 | 1 | 0 | 0 | 1 | Rn | Rd | |||||||||||||
U | immh | op |
integer d = UInt(Rd); integer n = UInt(Rn); if immh == '0000' then SEE(asimdimm); if immh<3>:Q == '10' then UNDEFINED; integer esize = 8 << HighestSetBit(immh); integer datasize = if Q == '1' then 128 else 64; integer elements = datasize DIV esize; integer shift = UInt(immh:immb) - esize; boolean src_unsigned; boolean dst_unsigned; case op:U of when '00' UNDEFINED; when '01' src_unsigned = FALSE; dst_unsigned = TRUE; when '10' src_unsigned = FALSE; dst_unsigned = FALSE; when '11' src_unsigned = TRUE; dst_unsigned = TRUE;
<V> |
Is a width specifier,
encoded in
|
<d> |
Is the number of the SIMD&FP destination register, in the "Rd" field. |
<n> |
Is the number of the first SIMD&FP source register, encoded in the "Rn" field. |
<Vd> |
Is the name of the SIMD&FP destination register, encoded in the "Rd" field. |
<T> |
Is an arrangement specifier,
encoded in
|
<Vn> |
Is the name of the SIMD&FP source register, encoded in the "Rn" field. |
<shift> |
For the scalar variant: is the left shift amount, in the range 0 to the operand width in bits minus 1,
encoded in
| ||||||||||||
For the vector variant: is the left shift amount, in the range 0 to the element width in bits minus 1,
encoded in
|
CheckFPAdvSIMDEnabled64(); bits(datasize) operand = V[n]; bits(datasize) result; integer element; boolean sat; for e = 0 to elements-1 element = Int(Elem[operand, e, esize], src_unsigned) << shift; (Elem[result, e, esize], sat) = SatQ(element, esize, dst_unsigned); if sat then FPSR.QC = '1'; V[d] = result;
Internal version only: isa v33.11seprel, AdvSIMD v29.05, pseudocode v2021-09_rel, sve v2021-09_rc3d ; Build timestamp: 2021-10-06T11:41
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