<!-- This defines instructions described in PowerISA Version 3.0 B Book 1 -->

<!-- This defines instructions that load from RAM to a register -->

<!-- Note that these pages also define equivalent store instructions, -->
<!-- these are described in fixedstore.mdwn -->

<!-- Section 3.3.2 This defines the Fixed-Point Load Instructions pages 47 - 53 -->
<!-- Section 3.3.3 Fixed-Point Store Instructions pages 54 - 56 -->
<!-- Section 3.3.3.1 64-bit Fixed-Point Store Instructions pages 57 -->
<!-- Section 3.3.4 Fixed Point Load and Store Quadword Instructions pages 58 - 59 -->
<!-- Section 3.3.5 Fixed-Point Load and Store with Byte Reversal Instructions page 60 -->
<!-- Section 3.3.5.1 64-Bit Load and Store with Byte Reversal Instructions page 61 -->
<!-- Section 3.3.6 Fixed-Point Load and Store Multiple Instructions page 62 -->


<!-- Section 3.3.2 This defines the Fixed-Point Load Instructions pages 47 - 53 -->

<!-- The byte, halfword, word, or doubleword in storage addressed by EA is loaded -->
<!-- into register RT. -->

<!-- Many of the Load instructions have an “update” form, in which register RA is -->
<!-- updated with the effective address. For these forms, if RA!=0 and RA!=RT, the -->
<!-- effective address is placed into register RA and the storage element (byte, -->
<!-- halfword, word, or doubleword) addressed by EA is loaded into RT. -->


# Load Byte and Zero Shifted Indexed

X-Form

* lbzsx RT,RA,RB,sm

Pseudo-code:

    b <- (RA|0)
    EA <- b + (RB) << (sm+1)
    RT <- ([0] * (XLEN-8)) || MEM(EA, 1)

Special Registers Altered:

    None

# Load Byte and Zero Shifted with Update Indexed

X-Form

* lbzsux RT,RA,RB,sm

Pseudo-code:

    EA <- (RA) + (RB) << (sm+1)
    RT <- ([0] * (XLEN-8)) || MEM(EA, 1)
    RA <- EA

Special Registers Altered:

    None

# Load Halfword and Zero Shifted Indexed

X-Form

* lhzsx RT,RA,RB,sm

Pseudo-code:

    b <- (RA|0)
    EA <- b + (RB) << (sm+1)
    RT <- ([0] * (XLEN-16)) || MEM(EA, 2)

Special Registers Altered:

    None

# Load Halfword and Zero Shifted with Update Indexed

X-Form

* lhzsux RT,RA,RB,sm

Pseudo-code:

    EA <- (RA) + (RB) << (sm+1)
    RT <- ([0] * (XLEN-16)) || MEM(EA, 2)
    RA <- EA

Special Registers Altered:

    None

# Load Halfword Algebraic Shifted Indexed

X-Form

* lhasx RT,RA,RB,sm

Pseudo-code:

    b <- (RA|0)
    EA <- b + (RB) << (sm+1)
    RT <- EXTS(MEM(EA, 2))

Special Registers Altered:

    None

# Load Halfword Algebraic Shifted with Update Indexed

X-Form

* lhasux RT,RA,RB,sm

Pseudo-code:

    EA <- (RA) + (RB) << (sm+1)
    RT <- EXTS(MEM(EA, 2))
    RA <- EA

Special Registers Altered:

    None

# Load Word and Zero Indexed

X-Form

* lwzx RT,RA,RB

Pseudo-code:

    b <- (RA|0)
    EA <- b + (RB)
    RT <- [0] * 32 || MEM(EA, 4)

Special Registers Altered:

    None

# Load Word and Zero with Update Indexed

X-Form

* lwzux RT,RA,RB

Pseudo-code:

    EA <- (RA) + (RB)
    RT <- [0] * 32 || MEM(EA, 4)
    RA <- EA

Special Registers Altered:

    None

# Load Word Algebraic Indexed

X-Form

* lwax RT,RA,RB

Pseudo-code:

    b <- (RA|0)
    EA <- b + (RB)
    RT <- EXTS(MEM(EA, 4))

Special Registers Altered:

    None

# Load Word Algebraic with Update Indexed

X-Form

* lwaux RT,RA,RB

Pseudo-code:

    EA <- (RA) + (RB)
    RT <- EXTS(MEM(EA, 4))
    RA <- EA

Special Registers Altered:

    None

# Load Doubleword Indexed

X-Form

* ldx RT,RA,RB

Pseudo-code:

    b <- (RA|0)
    EA <- b + (RB)
    RT <- MEM(EA, 8)

Special Registers Altered:

    None

# Load Doubleword with Update Indexed

X-Form

* ldux RT,RA,RB

Pseudo-code:

    EA <- (RA) + (RB)
    RT <- MEM(EA, 8)
    RA <- EA

Special Registers Altered:

    None

<!-- byte-reverse shifted -->

# Load Halfword Byte-Reverse Indexed

X-Form

* lhbrx RT,RA,RB

Pseudo-code:

    b <- (RA|0)
    EA <- b + (RB)
    load_data <- MEM(EA, 2)
    RT <- [0]*48 || load_data[8:15] || load_data[0:7]

Special Registers Altered:

    None

# Load Word Byte-Reverse Indexed

X-Form

* lwbrx RT,RA,RB

Pseudo-code:

    b <- (RA|0)
    EA <- b + (RB)
    load_data <- MEM(EA, 4)
    RT <- ([0] * 32 || load_data[24:31] || load_data[16:23]
                    || load_data[8:15]  || load_data[0:7])

Special Registers Altered:

    None


<!-- Section 3.3.5.1 64-Bit Load and Store with Byte Reversal Instructions page 61 -->

# Load Doubleword Byte-Reverse Indexed

X-Form

* ldbrx RT,RA,RB

Pseudo-code:

    b <- (RA|0)
    EA <- b + (RB)
    load_data <- MEM(EA, 8)
    RT <- (load_data[56:63] || load_data[48:55]
        || load_data[40:47] || load_data[32:39]
        || load_data[24:31] || load_data[16:23]
        || load_data[8:15]  || load_data[0:7])

Special Registers Altered:

    None