MIPS Assembly/Pseudoinstructions

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MIPS Assembly

The MIPS instruction set is very small, so to do more complicated tasks we need to employ assembler macros called pseudoinstructions.

Contents 1 List of Pseudoinstructions 2 Branch Pseudoinstructions 3 Other Pseudoinstructions 4 $at Register

[edit] List of Pseudoinstructions

The following is a list of the standard MIPS instructions that are implemented as pseudoinstructions:

• blt
• bgt
• ble
• blt
• bge
• li
• move

[edit] Branch Pseudoinstructions

Branch if less than (blt)

The blt instruction compares 2 registers, treating them as signed integers, and takes a branch if one register is less than another.

blt $8, $9, 4

translates to

slt $1, $8, $9
bne $1, $0, 4

[edit] Other Pseudoinstructions

Load Immediate (li)

The li pseudo instruction loads an immediate value into a register.

li $1, 0x3BF20

translates to

lui $2, 0x0003
ori $1, $2, 0xBF20

Move (move)

The move pseudo instruction moves the contents of one register into another register.

move $1, $2

translates to

add $1, $2, $0

[edit] $at Register