Search all intrinsics
SIMD ISAReturn TypeNameArgumentsInstruction Group
Neonint64x2_tvmlsl_laneq_s32(int64x2_t a, int32x2_t b, int32x4_t v, const int lane)Scalar arithmetic / Vector multiply-subtract by scalar
Description
Signed Multiply-Subtract Long (vector, by element). This instruction multiplies each vector element in the lower or upper half of the first source SIMD&FP register by the specified vector element of the second source SIMD&FP register and subtracts the results from the vector elements of the destination SIMD&FP register. The destination vector elements are twice as long as the elements that are multiplied.
Results
Vd.2D result
This intrinsic compiles to the following instructions:

SMLSL Vd.2D,Vn.2S,Vm.S[lane]

Argument Preparation
a register: Vd.2Db register: Vn.2Sv register: Vm.4Slane minimum: 0; maximum: 3
Architectures
A64

Operation

CheckFPAdvSIMDEnabled64();
bits(datasize)   operand1 = Vpart[n, part];
bits(datasize)   operand2 = Vpart[m, part];
bits(2*datasize) operand3 = V[d];
bits(2*datasize) result;
integer element1;
integer element2;
bits(2*esize) product;
bits(2*esize) accum;

for e = 0 to elements-1
    element1 = Int(Elem[operand1, e, esize], unsigned);
    element2 = Int(Elem[operand2, e, esize], unsigned);
    product = (element1 * element2)<2*esize-1:0>;
    if sub_op then
        accum = Elem[operand3, e, 2*esize] - product;
    else
        accum = Elem[operand3, e, 2*esize] + product;
    Elem[result, e, 2*esize] = accum;

V[d] = result;