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MUL, MULS

Multiply multiplies two register values. The least significant 32 bits of the result are written to the destination register. These 32 bits do not depend on whether the source register values are considered to be signed values or unsigned values.

Optionally, it can update the condition flags based on the result. In the T32 instruction set, this option is limited to only a few forms of the instruction. Use of this option adversely affects performance on many implementations.

It has encodings from the following instruction sets: A32 ( A1 ) and T32 ( T1 and T2 ) .

A1

Decode for all variants of this encoding

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

T1

Decode for this encoding

let d : integer = UInt(Rdm); let n : integer = UInt(Rn); let m : integer = UInt(Rdm); let setflags : boolean = !InITBlock();

T2

Decode for this encoding

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

Assembler Symbols