46. Stack in MIPS assembly

• The stack pointer is in register $sp

  • $sp contains the address of the top of the stack

  • OS loader initializes $sp when the program is loaded

  • At runtime, $sp is your responsibility!

• For example, stack frames in procedures are managed like this:

  
      addiu $sp, $sp, -24      # allocate 6 words on the stack
      ...
      sw    $t0, 16($sp)       # save $t0 in stack frame
      ...
      lw    $t0, 16($sp)       # restore $t0 from the stack frame
      ...
      addiu $sp, $sp, 24       # deallocate 6 words on the stack