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VQDMULH

Vector Saturating Doubling Multiply Returning High Half multiplies corresponding elements in two vectors, doubles the results, and places the most significant half of the final results in the destination vector. The results are truncated, for rounded results see VQRDMULH.

The second operand can be a scalar instead of a vector. For more information about scalars see Advanced SIMD scalars.

If any of the results overflow, they are saturated. The cumulative saturation bit, FPSCR.QC, is set if saturation occurs. For details see Pseudocode details of saturation.

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 A2 ) and T32 ( T1 and T2 ) .

A1

Decode for all variants of this encoding

if Q == '1' && (Vd[0] == '1' || Vn[0] == '1' || Vm[0] == '1') then Undefined(); end; if size == '00' || size == '11' then Undefined(); end; let scalar_form : boolean = FALSE; let esize : integer{} = 8 << UInt(size); let elements : integer = 64 DIV esize; let d : integer = UInt(D::Vd); let n : integer = UInt(N::Vn); let m : integer = UInt(M::Vm); let regs : integer = if Q == '0' then 1 else 2; let index : integer = ARBITRARY : integer;

A2

Decode for all variants of this encoding

if size == '11' then See("Related encodings"); end; if size == '00' then Undefined(); end; if Q == '1' && (Vd[0] == '1' || Vn[0] == '1') then Undefined(); end; let scalar_form : boolean = TRUE; let d : integer = UInt(D::Vd); let n : integer = UInt(N::Vn); let m : integer = if size == '01' then UInt(Vm[2:0]) else UInt(Vm); let index : integer = if size == '01' then UInt(M::Vm[3]) else UInt(M); let regs : integer = if Q == '0' then 1 else 2; let esize : integer{} = 8 << UInt(size); let elements : integer = 64 DIV esize;

T1

Decode for all variants of this encoding

if Q == '1' && (Vd[0] == '1' || Vn[0] == '1' || Vm[0] == '1') then Undefined(); end; if size == '00' || size == '11' then Undefined(); end; let scalar_form : boolean = FALSE; let esize : integer{} = 8 << UInt(size); let elements : integer = 64 DIV esize; let d : integer = UInt(D::Vd); let n : integer = UInt(N::Vn); let m : integer = UInt(M::Vm); let regs : integer = if Q == '0' then 1 else 2; let index : integer = ARBITRARY : integer;

T2

Decode for all variants of this encoding

if size == '11' then See("Related encodings"); end; if size == '00' then Undefined(); end; if Q == '1' && (Vd[0] == '1' || Vn[0] == '1') then Undefined(); end; let scalar_form : boolean = TRUE; let d : integer = UInt(D::Vd); let n : integer = UInt(N::Vn); let m : integer = if size == '01' then UInt(Vm[2:0]) else UInt(Vm); let index : integer = if size == '01' then UInt(M::Vm[3]) else UInt(M); let regs : integer = if Q == '0' then 1 else 2; let esize : integer{} = 8 << UInt(size); let elements : integer = 64 DIV esize;

Assembler Symbols