CCMP (register)

Conditional Compare (register) sets the value of the condition flags to the result of the comparison of two registers if the condition is TRUE, and an immediate value otherwise.

313029282726252423222120191817161514131211109876543210
sf1111010010Rmcond00Rn0nzcv
op

32-bit (sf == 0)

CCMP <Wn>, <Wm>, #<nzcv>, <cond>

64-bit (sf == 1)

CCMP <Xn>, <Xm>, #<nzcv>, <cond>

integer n = UInt(Rn); integer m = UInt(Rm); integer datasize = if sf == '1' then 64 else 32; boolean sub_op = (op == '1'); bits(4) condition = cond; bits(4) flags = nzcv;

Assembler Symbols

<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.

<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.

<nzcv>

Is the flag bit specifier, an immediate in the range 0 to 15, giving the alternative state for the 4-bit NZCV condition flags, encoded in the "nzcv" field.

<cond>

Is one of the standard conditions, encoded in the "cond" field in the standard way.

Operation

if ConditionHolds(condition) then bits(datasize) operand1 = X[n]; bits(datasize) operand2 = X[m]; bit carry_in = '0'; if sub_op then operand2 = NOT(operand2); carry_in = '1'; (-, flags) = AddWithCarry(operand1, operand2, carry_in); PSTATE.<N,Z,C,V> = flags;

Operational information

If PSTATE.DIT is 1:


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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