SBC

Subtract with Carry subtracts a register value and the value of NOT (Carry flag) from a register value, and writes the result to the destination register.

This instruction is used by the alias NGC.

313029282726252423222120191817161514131211109876543210
sf1011010000Rm000000RnRd
opS

32-bit (sf == 0)

SBC <Wd>, <Wn>, <Wm>

64-bit (sf == 1)

SBC <Xd>, <Xn>, <Xm>

integer d = UInt(Rd); integer n = UInt(Rn); integer m = UInt(Rm); constant integer datasize = 32 << UInt(sf);

Assembler Symbols

<Wd>

Is the 32-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, encoded in the "Rn" field.

<Wm>

Is the 32-bit name of the second general-purpose source register, encoded in the "Rm" field.

<Xd>

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

<Xn>

Is the 64-bit name of the first general-purpose source register, encoded in the "Rn" field.

<Xm>

Is the 64-bit name of the second general-purpose source register, encoded in the "Rm" field.

Alias Conditions

AliasIs preferred when
NGCRn == '11111'

Operation

bits(datasize) operand1 = X[n, datasize]; bits(datasize) operand2 = NOT(X[m, datasize]); bits(datasize) result; (result, -) = AddWithCarry(operand1, operand2, PSTATE.C); X[d, datasize] = result;

Operational information

If PSTATE.DIT is 1:


Internal version only: aarchmrs v2024-03_relA, pseudocode v2024-03_rel, sve v2024-03_rel ; Build timestamp: 2024-03-26T09:45

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