Index

SUBPS

Subtract Pointer, setting Flags subtracts the 56-bit address held in the second source register from the 56-bit address held in the first source register, sign-extends the result to 64-bits, and writes the result to the destination register. It updates the condition flags based on the result of the subtraction.

This instruction is used by the alias CMPP.

Integer
(FEAT_MTE)

31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
1 0 1 1 1 0 1 0 1 1 0 Xm 0 0 0 0 0 0 Xn Xd

SUBPS <Xd>, <Xn|SP>, <Xm|SP>

if !IsFeatureImplemented(FEAT_MTE) then UNDEFINED;
integer d = UInt(Xd);
integer n = UInt(Xn);
integer m = UInt(Xm);

Assembler Symbols

<Xd>

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

Is the 64-bit name of the first source general-purpose register or stack pointer, encoded in the "Xn" field.
<Xm|SP>

Is the 64-bit name of the second general-purpose source register or stack pointer, encoded in the "Xm" field.

Alias Conditions

Alias Is preferred when
CMPP S == '1' && Xd == '11111'

Operation

bits(64) operand1 = if n == 31 then SP[] else X[n, 64];
bits(64) operand2 = if m == 31 then SP[] else X[m, 64];
operand1 = SignExtend(operand1<55:0>, 64);
operand2 = SignExtend(operand2<55:0>, 64);

bits(64) result;
bits(4) nzcv;

operand2 = NOT(operand2);
(result, nzcv) = AddWithCarry(operand1, operand2, '1');

PSTATE.<N,Z,C,V> = nzcv;
X[d, 64] = result;