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SMULWB, SMULWT

Signed Multiply (word by halfword) multiplies a signed 32-bit quantity and a signed 16-bit quantity. The signed 16-bit quantity is taken from either the bottom or the top half of its source register. The other half of the second source register is ignored. The top 32 bits of the 48-bit product are written to the destination register. The bottom 16 bits of the 48-bit product are ignored. No overflow is possible during this instruction.

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

A1

Decode for all variants of this encoding

let d : integer = UInt(Rd); let n : integer = UInt(Rn); let m : integer = UInt(Rm); let m_high : boolean = (M == '1'); if d == 15 || n == 15 || m == 15 then UnpredictableProcedure(); end;

T1

Decode for all variants of this encoding

let d : integer = UInt(Rd); let n : integer = UInt(Rn); let m : integer = UInt(Rm); let m_high : boolean = (M == '1'); // Armv8-A removes UNPREDICTABLE for R13 if d == 15 || n == 15 || m == 15 then UnpredictableProcedure(); end;

Assembler Symbols