Index

CSEL

If the condition is true, Conditional Select writes the value of the first source register to the destination register. If the condition is false, it writes the value of the second source register 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
sf 0 0 1 1 0 1 0 1 0 0 Rm cond 0 0 Rn Rd
op o2

32-bit (sf == 0)

CSEL <Wd>, <Wn>, <Wm>, <cond>

64-bit (sf == 1)

CSEL <Xd>, <Xn>, <Xm>, <cond>

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.
<cond>

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

Operation

bits(datasize) result;
if ConditionHolds(cond) then
    result = X[n, datasize];
else
    result = X[m, datasize];

X[d, datasize] = result;

Operational information

If PSTATE.DIT is 1: