The Exclusive Or Register instruction performs a logical bit by bit “exclusive or” between two registers. Operand 1, the target, is a register and Operand 2, the source, also specifies a register. The fullword in Operand 1 is exclusive or-ed internally with the fullword in Operand 2, and the result is placed in Operand 1. The table below shows the results of “exclusive or-ing” two bits together.

Bit 1 Bit 2 Result

0 0 0

0 1 1

1 0 1

1 1 0

This instruction sets the condition code as follows:

0 if all target bits are set to 0. Test this condition with BZ or BNZ.

1 if any target bit is set to 1. Test this condition with BM or BNM.

Some Unrelated Exclusive Or Registers

R4 = X’FFFFFFFF’ ALL 1’S

R5 = X’00000000’ ALL 0’S

R6 = X’0000148C’ 00000000000000000001010010001100

R7 = X’000014AB’ 00000000000000000001010010101011

XR R4,R4 R4 = X’00000000’ Condition Code = 0

XR R4,R5 R4 = X’FFFFFFFF’ Condition Code = 1

XR R4,R6 R4 = X’FFFFEB73’ Condition Code = 1

XR R4,R7 R4 = X’FFFFEB54’ Condition Code = 1

XR R5,R6 R5 = X’0000148C’ Condition Code = 1

XR R5,R7 R5 = X’000014AB’ Condition Code = 1

XR R6,R7 R6 = X’00000027’ Condition Code = 1

XR R7,R7 R7 = X’00000000’ Condition Code = 0