UMADDL -- A64

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UMADDL

This instruction multiplies two 32-bit register values, adds a 64-bit register value, and writes the result to the 64-bit destination register.

Decode for this encoding

let d : integer{} = UInt(Rd); let n : integer{} = UInt(Rn); let m : integer{} = UInt(Rm); let a : integer{} = UInt(Ra);

Assembler Symbols

<Xd>	Is the 64-bit name of the general-purpose destination register, encoded in the "Rd" field.

<Wn>	Is the 32-bit name of the first general-purpose source register holding the multiplicand, encoded in the "Rn" field.

<Wm>	Is the 32-bit name of the second general-purpose source register holding the multiplier, encoded in the "Rm" field.

<Xa>	Is the 64-bit name of the third general-purpose source register holding the addend, encoded in the "Ra" field.

Alias Conditions

Alias	Is preferred when
UMULL	Ra == '11111'

Operation

let operand1 : bits(32) = X{}(n); let operand2 : bits(32) = X{}(m); let operand3 : bits(64) = X{}(a); let result : integer = UInt(operand3) + (UInt(operand1) * UInt(operand2)); X{64}(d) = result[63:0];

Operational information

This instruction is a data-independent-time instruction as described in About PSTATE.DIT.

2025-09_rel_asl1 2026-03-12 12:57:38