VMS Help MACRO, VAX MACRO Assembler, Vector Instructions, VGATH  *Conan The Librarian (sorry for the slow response - running on an old VAX)

    Gather Memory Data into Vector Register

    Format:

      VGATHL   [/M[0|1]]    base, Vb, Vc

      VGATHQ   [/M[0|1]]    base, Vb, Vc

    Architecture

    Format
    opcode   cntrl.rw, base.ab
    opcodes

    35FD    VGATHL    Gather Longword Vector from Memory to Vector
                      Register

    37FD    VGATHQ    Gather Quadword Vector from Memory to Vector
                      Register

    vector_control_word

             1 1 1 1 1
             5 4 3 2 1     8 7     4 3     0
            +-+-+-+-+-------+-------+-------+
            |M|M|M| |       |       |       |
            |O|T|I|0|   0   |  Vb   |  Vc   |
            |E|F| | |       |       |       |
            +-+-+-+-+-------+-------+-------+
    exceptions

       access control violation
       translation not valid
       vector alignment

    operation
      FOR i <- 0 TO VLR-1
        BEGIN
          addr <- base + Vb[i]<31:0>
          IF {{MOE EQL 0} OR {{MOE EQL 1} AND {VMR<i> EQL MTF}}} THEN
            BEGIN
              IF {addr unaligned} THEN
                 {Vector Alignment Exception}

              IF VGATHL THEN
                 Vc[i] <- (addr)<31:0>
              IF VGATHQ THEN
                 Vc[i] <- (addr)<63:0>
            END
        END