8 Stack and shit

procedure call instructions

• procedure return

  • jumps and likns registers
    • jalr x0 0(x1) commonly used
    • jalr rd, imm(rs1) general form
      • like jal, but jumps to rs1+imm instead of PC+2*imm
    • imm is a 12 bit immediate value offset

Memory layout

top is kernal space (os)

Reseverd memory

• bios
• device

local and global memory

• local memory will save the info into local

• global will save it into the stack

Stack and risc V

• to go to a specific point on the stack we need to do a “push and pop” using

  • addi sp, sp, -12 we are moving the stack to make room for 3 items (12 bites)
  • then we must do the opposite and add 12 to bring it back