VMULL (by scalar)

Vector Multiply Long multiplies each element in a vector by a scalar, and places the results in a second vector. The destination vector elements are twice as long as the elements that are multiplied.

For more information about scalars see Advanced SIMD scalars.

Depending on settings in the CPACR, NSACR, and HCPTR registers, and the Security state and PE mode in which the instruction is executed, an attempt to execute the instruction might be undefined, or trapped to Hyp mode. For more information see Enabling Advanced SIMD and floating-point support.

It has encodings from the following instruction sets: A32 ( A1 ) and T32 ( T1 ) .

A1

313029282726252423222120191817161514131211109876543210
1111001U1D!= 11VnVd1010N1M0Vm
size

A1

VMULL{<c>}{<q>}.<dt> <Qd>, <Dn>, <Dm>[<index>]

if size == '11' then SEE "Related encodings"; if size == '00' || Vd<0> == '1' then UNDEFINED; unsigned = (U == '1'); long_destination = TRUE; floating_point = FALSE; d = UInt(D:Vd); n = UInt(N:Vn); regs = 1; integer esize; integer elements; integer index; integer m; if size == '01' then esize = 16; elements = 4; m = UInt(Vm<2:0>); index = UInt(M:Vm<3>); if size == '10' then esize = 32; elements = 2; m = UInt(Vm); index = UInt(M);

T1

15141312111098765432101514131211109876543210
111U11111D!= 11VnVd1010N1M0Vm
size

T1

VMULL{<c>}{<q>}.<dt> <Qd>, <Dn>, <Dm>[<index>]

if size == '11' then SEE "Related encodings"; if size == '00' || Vd<0> == '1' then UNDEFINED; unsigned = (U == '1'); long_destination = TRUE; floating_point = FALSE; d = UInt(D:Vd); n = UInt(N:Vn); regs = 1; integer esize; integer elements; integer index; integer m; if size == '01' then esize = 16; elements = 4; m = UInt(Vm<2:0>); index = UInt(M:Vm<3>); if size == '10' then esize = 32; elements = 2; m = UInt(Vm); index = UInt(M);

Related encodings: See Advanced SIMD data-processing for the T32 instruction set, or Advanced SIMD data-processing for the A32 instruction set.

Assembler Symbols

<c>

For encoding A1: see Standard assembler syntax fields. This encoding must be unconditional.

For encoding T1: see Standard assembler syntax fields.

<q>

See Standard assembler syntax fields.

<dt>

Is the data type for the scalar and the elements of the operand vector, encoded in U:size:

U size <dt>
0 01 S16
0 10 S32
1 01 U16
1 10 U32
<Qd>

Is the 128-bit name of the SIMD&FP destination register, encoded in the "D:Vd" field as <Qd>*2.

<Dn>

Is the 64-bit name of the first SIMD&FP source register, encoded in the "N:Vn" field.

<Dm>

Is the 64-bit name of the second SIMD&FP source register, encoded in the "Vm<2:0>" field when <dt> is S16 or U16, otherwise the "Vm" field.

<index>

Is the element index in the range 0 to 3, encoded in the "M:Vm<3>" field when <dt> is S16 or U16, otherwise in range 0 to 1, encoded in the "M" field.

Operation

if ConditionPassed() then EncodingSpecificOperations(); CheckAdvSIMDEnabled(); op2 = Elem[Din[m],index,esize]; op2val = Int(op2, unsigned); for r = 0 to regs-1 for e = 0 to elements-1 op1 = Elem[Din[n+r],e,esize]; op1val = Int(op1, unsigned); if floating_point then Elem[D[d+r],e,esize] = FPMul(op1, op2, StandardFPSCRValue()); else if long_destination then Elem[Q[d>>1],e,2*esize] = (op1val*op2val)<2*esize-1:0>; else Elem[D[d+r],e,esize] = (op1val*op2val)<esize-1:0>;


Internal version only: isa v01_31, pseudocode v2023-06_rel, sve v2023-06_rel ; Build timestamp: 2023-07-04T18:06

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