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13.130 SMULWy

Signed Multiply Wide, with one 32-bit and one 16-bit operand, providing the top 32 bits of the result.


SMULW<y>{cond} {Rd}, Rn, Rm



is either B or T. B meansuse the bottom half (bits [15:0]) of Rm, T meansuse the top half (bits [31:16]) of Rm.


is an optional condition code.


is the destination register.

Rn, Rm

are the registers holding the values to be multiplied.


SMULWy multiplies the signed integerfrom the selected half of Rm bythe signed integer from Rn, andplaces the upper 32-bits of the 48-bit result in Rd.

Register restrictions

You cannot use PC for any operand.

You can use SP in A32 instructions but this is deprecated. You cannot use SP in T32 instructions.

Condition flags

This instruction does not affect the N, Z, C, or V flags.


The 32-bit instruction is available in A32 and T32.

There is no 16-bit version of this instruction in T32.