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What is .d2x in the instruction add.d2x?

It's clear what is .d2 in add . d2, but where could I read about .d2x?

  • Hi Stanislav,

    .d2x refer to the cross path for the register file.

    Extract from

    2.4 Register File Cross Paths

    Each functional unit reads directly from and writes directly to the register file within its own data path. That

    is, the .L1, .S1, .D1, and .M1 units write to register file A and the .L2, .S2, .D2, and .M2 units write to

    register file B. The register files are connected to the opposite-side register file's functional units via the 1X

    and 2X cross paths. These cross paths allow functional units from one data path to access a 32-bit

    operand from the opposite side register file. The 1X cross path allows the functional units of data path A to

    read their source from register file B, and the 2X cross path allows the functional units of data path B to

    read their source from register file A.

    || SUB .S2X B4,A4,B3 ; 2X cross paths using A4

    || AND .D2X B5,A4,B4 ; 2X cross paths using A4

    --------

  • Thank you very much!