It is a multiple of two. Such addresses have a zero in the low-order bit.
Only one store halfword instruction is needed. The low-order two bytes of the designated register are copied to memory, no matter what the upper two bytes are. Of course, the register is not changed when its data is copied to memory.
sh t,off(b) # Halfword at off+b <— low-order # two bytes from $t. # b is a base register. # off is 16-bit two's complement.
MIPS arithmetic instructions that use registers
always use full registers, regardless of
how data was
loaded into the register.
For example, an
instruction does a full 32-bit addition
even if one of the operand registers was loaded with
Perform these two addition problems:
0110 1110 0000 0000 0000 0000 0000 0000 0110 1110 1100 0110 0000 0000 0000 0000 0000 0000 1100 0110