Claims:WE CLAIM:

1. An apparatus comprising:
a matrix operations accelerator circuit comprising a two-dimensional grid of fused multiply accumulate circuits;
a first plurality of registers that represents at least one first input two-dimensional matrix coupled to the matrix operations accelerator circuit;
a second plurality of registers that represents at least one second input two-dimensional matrix coupled to the matrix operations accelerator circuit;
a decoder, of a core coupled to the matrix operations accelerator circuit, to decode a single instruction into a decoded single instruction, the single instruction including a field that identifies a resultant storage; and
an execution circuit of the core to execute the decoded single instruction to:
switch the matrix operations accelerator circuit from a first mode where a respective output of each of a first proper subset of fused multiply accumulate circuits of the two-dimensional grid is transmitted downstream to a respective input of each of a second proper subset of fused multiply accumulate circuits of the two-dimensional grid to form output values from the at least one first input two-dimensional matrix and the at least one second input two-dimensional matrix, and store the output values in the resultant storage, to a second mode where the respective output of each of the first proper subset of fused multiply accumulate circuits of the two-dimensional grid form first output values from a first subset of the at least one first input two-dimensional matrix and the at least one second input two-dimensional matrix, and store the first output values in the resultant storage, and a respective output of each of the second proper subset of fused multiply accumulate circuits of the two-dimensional grid form second output values from a second subset of the at least one first input two-dimensional matrix and the at least one second input two-dimensional matrix, and store the second output values in the resultant storage.

2. The apparatus of claim 1, wherein the single instruction comprises a second field to indicate the matrix operations accelerator circuit is to execute in the first mode when the second field is a first value and in the second mode when the second field is a second value.

3. The apparatus of claim 2, wherein the second field is an immediate of the single instruction.

4. The apparatus of claim 1, wherein the resultant storage is a third plurality of registers that represents at least one output two-dimensional matrix formed by execution of the decoded single instruction.

5. The apparatus of claim 4, wherein the execution of the decoded single instruction is to:
in the first mode, add values from the third plurality of registers that represents at least one third input two-dimensional matrix initially stored in the third plurality of registers to the output values to form updated output values and store the updated output values, instead of the output values, into the resultant storage, and
in the second mode, add values from the at least one third input two-dimensional matrix initially stored in the third plurality of registers to the first output values and the second output values to form updated first output values and updated second output values and store the updated first output values and updated second output values, instead of the first output values and the second output values, into the resultant storage.

6. The apparatus of claim 1, wherein the execution of the decoded single instruction is to:
in the first mode, add values from at least one third input two-dimensional matrix initially stored in a third plurality of registers to the output values to form updated output values and store the updated output values, instead of the output values, into the resultant storage, and
in the second mode, add values from the at least one third input two-dimensional matrix initially stored in the third plurality of registers to the first output values and the second output values to form updated first output values and updated second output values and store the updated first output values and updated second output values, instead of the first output values and the second output values, into the resultant storage.

7. The apparatus of claim 1, wherein the resultant storage is a third plurality of registers that represents a plurality of output two-dimensional matrices formed by execution of the decoded single instruction.

8. The apparatus of any one of claims 1-7, wherein the first proper subset of fused multiply accumulate circuits is one of a row or a column of the two-dimensional grid of fused multiply accumulate circuits and the second proper subset of fused multiply accumulate circuits is another of the one of the row or the column of the two-dimensional grid of fused multiply accumulate circuits.

9. A method comprising:
decoding, with a decoder of a processor core, a single instruction into a decoded single instruction, wherein the processor core is coupled to a matrix operations accelerator circuit comprising a two-dimensional grid of fused multiply accumulate circuits, the matrix operations accelerator circuit is coupled to a first plurality of registers that represents at least one first input two-dimensional matrix and a second plurality of registers that represents at least one second input two-dimensional matrix, and the single instruction includes a field that identifies a resultant storage; and
executing the decoded single instruction with an execution circuit of the processor core to:
switch the matrix operations accelerator circuit from a first mode where a respective output of each of a first proper subset of fused multiply accumulate circuits of the two-dimensional grid is transmitted downstream to a respective input of each of a second proper subset of fused multiply accumulate circuits of the two-dimensional grid to form output values from the at least one first input two-dimensional matrix and the at least one second input two-dimensional matrix, and store the output values in the resultant storage, to a second mode where the respective output of each of the first proper subset of fused multiply accumulate circuits of the two-dimensional grid form first output values from a first subset of the at least one first input two-dimensional matrix and the at least one second input two-dimensional matrix, and store the first output values in the resultant storage, and a respective output of each of the second proper subset of fused multiply accumulate circuits of the two-dimensional grid form second output values from a second subset of the at least one first input two-dimensional matrix and the at least one second input two-dimensional matrix, and store the second output values in the resultant storage.

10. The method of claim 9, wherein the single instruction comprises a second field indicating that the matrix operations accelerator circuit is to execute in the first mode when the second field is a first value and in the second mode when the second field is a second value.

11. The method of claim 10, wherein the second field is an immediate of the single instruction.

12. The method of claim 9, wherein the resultant storage is a third plurality of registers that represents at least one output two-dimensional matrix formed by execution of the decoded single instruction.

13. The method of claim 12, wherein the executing the decoded single instruction is to:
in the first mode, add values from the third plurality of registers that represents at least one third input two-dimensional matrix initially stored in the third plurality of registers to the output values to form updated output values and store the updated output values, instead of the output values, into the resultant storage, and
in the second mode, add values from the at least one third input two-dimensional matrix initially stored in the third plurality of registers to the first output values and the second output values to form updated first output values and updated second output values and store the updated first output values and updated second output values, instead of the first output values and the second output values, into the resultant storage.

14. The method of claim 9, wherein the executing the decoded single instruction is to:
in the first mode, add values from at least one third input two-dimensional matrix initially stored in a third plurality of registers to the output values to form updated output values and store the updated output values, instead of the output values, into the resultant storage, and
in the second mode, add values from the at least one third input two-dimensional matrix initially stored in the third plurality of registers to the first output values and the second output values to form updated first output values and updated second output values and store the updated first output values and updated second output values, instead of the first output values and the second output values, into the resultant storage.

15. The method of claim 9, wherein the resultant storage is a third plurality of registers that represents a plurality of output two-dimensional matrices formed by execution of the decoded single instruction.

16. The method of any one of claims 9-15, wherein the first proper subset of fused multiply accumulate circuits is one of a row or a column of the two-dimensional grid of fused multiply accumulate circuits and the second proper subset of fused multiply accumulate circuits is another of the one of the row or the column of the two-dimensional grid of fused multiply accumulate circuits.