Compare (immediate) subtracts an immediate value from a register value. It updates the condition flags based on the result, and discards the result.
It has encodings from the following instruction sets: A32 ( A1 ) and T32 ( T1 and T2 ) .
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 |
!= 1111 | 0 | 0 | 1 | 1 | 0 | 1 | 0 | 1 | Rn | (0) | (0) | (0) | (0) | imm12 | |||||||||||||||||
cond |
n = UInt(Rn); imm32 = A32ExpandImm(imm12);
15 | 14 | 13 | 12 | 11 | 10 | 9 | 8 | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 |
0 | 0 | 1 | 0 | 1 | Rn | imm8 |
n = UInt(Rn); imm32 = ZeroExtend(imm8, 32);
15 | 14 | 13 | 12 | 11 | 10 | 9 | 8 | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 | 15 | 14 | 13 | 12 | 11 | 10 | 9 | 8 | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 |
1 | 1 | 1 | 1 | 0 | i | 0 | 1 | 1 | 0 | 1 | 1 | Rn | 0 | imm3 | 1 | 1 | 1 | 1 | imm8 |
n = UInt(Rn); imm32 = T32ExpandImm(i:imm3:imm8); if n == 15 then UNPREDICTABLE;
For more information about the constrained unpredictable behavior, see Architectural Constraints on UNPREDICTABLE behaviors.
<c> |
<q> |
<imm8> |
Is a 8-bit unsigned immediate, in the range 0 to 255, encoded in the "imm8" field. |
if ConditionPassed() then EncodingSpecificOperations(); (result, nzcv) = AddWithCarry(R[n], NOT(imm32), '1'); PSTATE.<N,Z,C,V> = nzcv;
Internal version only: isa v00_81, pseudocode v34.2.2 ; Build timestamp: 2018-03-28T20:43
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