The Or instruction performs a logical bit by bit “or” between a register and a fullword in memory. Operand 1, the target, is a register and Operand 2, the source, specifies a fullword in memory. The fullword in memory is or-ed internally with the fullword in the register and the result is placed in the register. The fullword in memory is not changed. The table below shows the results of “or-ing” two bits together.

Bit 1 Bit 2 Result

0 0 0

0 1 1

1 0 1

1 1 1

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 Ors

R4 = X’FFFFFFFF’ ALL 1’S

R5 = X’00000000’ ALL 0’S

R6 = X’0000148C’ 00000000000000000001010010001100

FIELD1 DC X’0000148C’

FIELD2 DC X’00000000’

FIELD3 DC X’FFFFFFFF’

FIELD4 DC X’12345678’

O R4,FIELD1 R4 = X’FFFFFFFF’ Condition Code = 1

O R4,FIELD2 R4 = X’FFFFFFFF’ Condition Code = 1

O R4,FIELD3 R4 = X’FFFFFFFF’ Condition Code = 1

O R4,FIELD4 R4 = X’FFFFFFFF’ Condition Code = 1

O R5,FIELD1 R5 = X’0000148C’ Condition Code = 1

O R5,FIELD2 R5 = X’00000000’ Condition Code = 0

O R5,FIELD3 R5 = X’FFFFFFFF’ Condition Code = 1

O R5,FIELD4 R5 = X’12345678’ Condition Code = 1

O R6,FIELD1 R6 = X’0000148C’ Condition Code = 1

O R6,FIELD2 R6 = X’0000148C’ Condition Code = 1

O R6,FIELD3 R6 = X’FFFFFFFF’ Condition Code = 1

O R6,FIELD4 R6 = X’123456FC’ Condition Code = 1