Subtract Pointer 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.
| 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 | 0 | 1 | 1 | 0 | 1 | 0 | 1 | 1 | 0 | Xm | 0 | 0 | 0 | 0 | 0 | 0 | Xn | Xd | ||||||||||||
if !HaveMTEExt() then UNDEFINED; integer d = UInt(Xd); integer n = UInt(Xn); integer m = UInt(Xm); boolean setflags = FALSE;
| <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. |
bits(64) operand1 = if n == 31 then SP[] else X[n]; bits(64) operand2 = if m == 31 then SP[] else X[m]; 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'); if setflags then PSTATE.<N,Z,C,V> = nzcv; X[d] = result;
Internal version only: isa v33.11seprel, AdvSIMD v29.05, pseudocode v2021-09_rel, sve v2021-09_rc3d ; Build timestamp: 2021-10-06T11:41
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