VSMMLA

The widening integer matrix multiply-accumulate instruction multiplies the 2x8 matrix of signed 8-bit integer values held in the first source vector by the 8x2 matrix of signed 8-bit integer values in the second source vector. The resulting 2x2 32-bit integer matrix product is destructively added to the 32-bit integer matrix accumulator held in the destination vector. This is equivalent to performing an 8-way dot product per destination element.

From Armv8.2, this is an optional instruction. ID_ISAR6.I8MM indicates whether this instruction is supported in the T32 and A32 instruction sets.

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

A1
(FEAT_AA32I8MM)

if !HaveAArch32Int8MatMulExt() then UNDEFINED; boolean op1_unsigned; boolean op2_unsigned; case B:U of when '00' op1_unsigned = FALSE; op2_unsigned = FALSE; when '01' op1_unsigned = TRUE; op2_unsigned = TRUE; when '10' op1_unsigned = TRUE; op2_unsigned = FALSE; when '11' UNDEFINED; if Vd<0> == '1' || Vn<0> == '1' || Vm<0> == '1' then UNDEFINED; integer d = UInt(D:Vd); integer n = UInt(N:Vn); integer m = UInt(M:Vm);

T1
(FEAT_AA32I8MM)

if InITBlock() then UNPREDICTABLE; if !HaveAArch32Int8MatMulExt() then UNDEFINED; boolean op1_unsigned; boolean op2_unsigned; case B:U of when '00' op1_unsigned = FALSE; op2_unsigned = FALSE; when '01' op1_unsigned = TRUE; op2_unsigned = TRUE; when '10' op1_unsigned = TRUE; op2_unsigned = FALSE; when '11' UNDEFINED; if Vd<0> == '1' || Vn<0> == '1' || Vm<0> == '1' then UNDEFINED; integer d = UInt(D:Vd); integer n = UInt(N:Vn); integer m = UInt(M:Vm);