dcbtst

Data Cache Block Touch for Store

dcbtst TH, RA, RB

Provides a hint that describes a block or data stream to which the program may perform a store access.

Details

The dcbtst instruction provides a hint that describes a block or data stream to which the program may perform a store access, or indicates the expected use thereof. The effective address (EA) is the sum of RA and RB.

Pseudocode Operation

Let the effective address (EA) be the sum (RA|0)+(RB).

The dcbtst instruction provides a hint that describes a block or data stream to which the program may perform store access. The instruction is also used to indicate imminent access or end of access to described store data streams.

Programming Note

See the Programming Notes at the beginning of this section.

Extended Mnemonics

Extended Mnemonic Equivalent Instruction
dcbtstds RA,RB,TH
dcbtstt RA,RB

Example

dcbtst 0, r4, r5

Encoding

Binary Layout
31
0
TH
6
RA
11
RB
16
246
/
 
Format X-form
Opcode 0x7C0001EC
Extension Base

Operands

  • TH
    Hint
  • RA
    Base
  • RB
    Index