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SMMLA, SMMLAR

Signed Most Significant Word Multiply Accumulate multiplies two signed 32-bit values, extracts the most significant 32 bits of the result, and adds an accumulate value.

Optionally, the instruction can specify that the result is rounded instead of being truncated. In this case, the constant 0x80000000 is added to the product before the high word is extracted.

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

A1

Decode for all variants of this encoding

if Ra == '1111' then See("SMMUL"); end; let d : integer = UInt(Rd); let n : integer = UInt(Rn); let m : integer = UInt(Rm); let a : integer = UInt(Ra); let round : boolean = (R == '1'); if d == 15 || n == 15 || m == 15 then UnpredictableProcedure(); end;

T1

Decode for all variants of this encoding

if Ra == '1111' then See("SMMUL"); end; let d : integer = UInt(Rd); let n : integer = UInt(Rn); let m : integer = UInt(Rm); let a : integer = UInt(Ra); let round : boolean = (R == '1'); // Armv8-A removes UNPREDICTABLE for R13 if d == 15 || n == 15 || m == 15 then UnpredictableProcedure(); end;

Assembler Symbols