xxmtacc

VSX Move to Accumulator

xxmtacc AT

Copies data from 4 adjacent VSRs into an Accumulator.

Details

Copies data from four consecutive VSRs (VSR[4×AT], VSR[4×AT+1], VSR[4×AT+2], VSR[4×AT+3]) into the 512-bit accumulator AT. This instruction transfers vector data from the VSR file into MMA accumulator state. This instruction requires MMA support and does not affect any condition registers or status fields.

Pseudocode Operation

ACC[AT][0:127] ← VSR[4×AT]
ACC[AT][128:255] ← VSR[4×AT+1]
ACC[AT][256:383] ← VSR[4×AT+2]
ACC[AT][384:511] ← VSR[4×AT+3]

Programming Note

Ensure VSX is enabled in the MSR before using xxmtacc; otherwise, a VSX_Unavailable exception will occur. This instruction moves data from four consecutive vector scalar registers into the accumulator, so verify register allocation to avoid unintended data movement.

Example

xxmtacc acc0

Encoding

Binary Layout
31
0
/
6
/
9
AT
11
153
/
 
Format X-form
Opcode 0x7C000131
Extension MMA
Registers Altered MSR

Operands

  • AT
    Target ACC