Test Bits Under Mask (TSTBUM)


Op Code (Hex) Extender Operand 1 Operand 2 Operand 3 [4, 5]
TSTBUMB 1C2A Branch options Source Mask Branch targets


TSTBUMI 182A Indicator options Source Mask Indicator targets

Operand 1: Character variable scalar or numeric variable scalar.

Operand 2: Character scalar or numeric scalar.

Operand 3 [4, 5]

Description  Selected bits from the leftmost byte of the source operand are tested to determine their bit values.

Based on the test, the resulting condition is used with the extender field to:

The source and the mask operands can be character or numeric. The leftmost byte of each of the operands is used in the operands. The operands are interpreted as bit strings. The testing is performed bit by bit with only those bits indicated by the mask operand being tested. A 1-bit in the mask operand specifies that the corresponding bit in the source value is to be tested. A 0-bit in the mask operand specifies that the corresponding bit in the source value is to be ignored.

Resultant Conditions  The selected bits of the bit string source operand are all zeros, all ones, or mixed ones and zeros. A mask operand of all zeros causes a zero resultant condition.

Authorization Required

Lock Enforcement

Exceptions

06 Addressing

08 Argument/Parameter

10 Damage Encountered

1C Machine-Dependent

20 Machine Support

22 Object Access

24 Pointer Specification

2C Program Execution

2E Resource Control Limit

36 Space Management

44 Protection Violation