<!-- Instructions here described in PowerISA Version 3.0 B Book 1 -->

<!-- Section 3.3.7 Fixed-Point Move Assist Instructions [Phased Out] pages 63 - 65 -->

<!-- The Move Assist instructions allow movement of an arbitrary sequence of bytes -->
<!-- from storage to registers or from registers to storage without concern for -->
<!-- alignment. These instructions can be used for a short move between arbitrary -->
<!-- storage locations or to initiate a long move between unaligned storage fields. -->


# Load String Word Immediate

X-Form

* lswi RT,RA,NB

Pseudo-code:

    EA <- (RA|0)
    if NB = 0 then n <-  32
    else           n <-  NB
    r <- RT - 1
    i <- 32
    do while n > 0
        if i = 32 then
            r <- (r + 1) % 32
            GPR(r) <- 0
        GPR(r)[i:i+7] <- MEM(EA, 1)
        i <- i + 8
        if i = 64 then i <- 32
        EA <- EA + 1
        n <- n - 1

Special Registers Altered:

    None

# Load String Word Indexed

X-Form

* lswx RT,RA,RB

Pseudo-code:

    b <- (RA|0)
    EA <- b + (RB)
    n <- XER[57:63]
    r <- RT - 1
    i <- 32
    RT <- undefined([0]*64)
    do while n > 0
        if i = 32 then
            r <-  (r + 1) % 32
            GPR(r) <- 0
        GPR(r)[i:i+7] <- MEM(EA, 1)
        i <-  i + 8
        if i = 64 then i <- 32
        EA <-  EA + 1
        n <- n - 1

Special Registers Altered:

    None

# Store String Word Immediate

X-Form

* stswi RS,RA,NB

Pseudo-code:

    EA <- (RA|0)
    if NB = 0 then n <-  32
    else           n <-  NB
    r <- RS - 1
    i <- 32
    do while n > 0
      if i = 32 then r <-  (r + 1) % 32
      MEM(EA, 1) <-  GPR(r)[i:i+7]
      i <-  i + 8
      if i = 64 then i <-  32
      EA <-  EA + 1
      n <- n - 1

Special Registers Altered:

    None

# Store String Word Indexed

X-Form

* stswx RS,RA,RB

Pseudo-code:

    b <- (RA|0)
    EA <- b + (RB)
    n <- XER[57:63]
    r <- RS - 1
    i <- 32
    do while n > 0
      if i = 32 then r <- (r + 1) % 32
      MEM(EA, 1) <- GPR(r)[i:i+7]
      i <-  i + 8
      if i = 64 then i <- 32
      EA <-  EA + 1
      n <- n - 1

Special Registers Altered:

    None

<!-- Checked March 2021 -->