lw
Load word
Loads the 32-bit word at the address $t2 plus an offset into $t1; the address must be word-aligned.
Used in
- Loads, stores and immediatesMIPS assembly
- Arrays and stringsMIPS assembly
- The stack and $spMIPS assembly
- jal, jr, and the course calling conventionMIPS assembly
- The bitmap display and keyboard registersMIPS assembly
- Exceptions and coprocessor 0MIPS assembly
- Variables in memory and constantsMIPS assembly
- Sum of an arrayMIPS assembly
- The largest elementMIPS assembly
- Stack arguments and a stack frameMIPS assembly
Forms
lw , ()
Pseudo-instructions
The assembler turns these into one or more real instructions.
Set $t1 to contents of effective memory word address
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Set $t1 to contents of memory word at label's address
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Read from label's address, reached through the %hi already in $t2
Operands
$t1- Any general-purpose register,
$0to$31, using its numeric or named spelling, such as$8or$t0($zerois$0;$rais$31). imm16- A signed 16-bit immediate,
-32768to32767. $t2- A general-purpose register. It may be the same register as
$t1. imm- An immediate value: a signed 16-bit value (
-32768to32767), an unsigned 16-bit value (0to65535) or a 32-bit value (-2147483648to4294967295). The assembler chooses a supported encoding for the value and other operands; a pseudoinstruction may expand into several instructions. label- A named address in the program, such as the start of a loop or a variable in
.data. imm32- A 32-bit immediate,
-2147483648to4294967295. Pseudoinstruction expansion may overwrite$at, losing its previous value.
The address must be word-aligned (divisible by 4). Example: 'lw $t0,0($sp)' loads the value at the top of the stack.
.data
.align 2
word: .word 0x12345678
.text
# Load the initialized word. Inspect $t0: 0x12345678.
la $t1, word
lw $t0, 0($t1)