MIPS Assembly Language Programming

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MIPS Assembly Language Programming
CDA 3101 Discussion Section 06
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Problem 1

• Write a function MinMax(X, N) to find the
  minimum and
• maximum of an array X of N integers. The address
  of the
• array is passed in a0, and the number of words
  in the array
• is passed in a1. The minimum and maximum are
  returned in
• registers v0 and v1 respectively.
• Also, write a short main program that
• Prompts the user for the value of N.
• Dynamically allocates memory for storing array X
  of N integers. (Remember, 4 bytes per integer!)
• Prompts user to enter N integers one by one to
  fill the array X.
• Calls the MinMax function to find and return the
  minimum and maximum of the array X.
• Prints the minimum and the maximum value.

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Problem 1

• Write a function MinMax(X, N) to find the
  minimum and
• maximum of an array X of N integers. The address
  of the
• array is passed in a0, and the number of words
  in the array
• is passed in a1. The minimum and maximum are
  returned in
• registers v0 and v1 respectively.
• Also, write a short main program that
• Prompts the user for the value of N.
• Dynamically allocates memory for storing array X
  of N integers. (Remember, 4 bytes per integer!)
• Prompts user to enter N integers one by one to
  fill the array X.
• Calls the MinMax function to find and return the
  minimum and maximum of the array X.
• Prints the minimum and the maximum value.

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Problem 2

• Implement a recursive function fib(n) to compute
  Fibonacci numbers. Also write a short main
  function that prompts the user to enter the
  integer N, calls the function fib(N) and prints
  the value returned by the fib(N) function.Note
  that
• fib(0)0 fib(1)1
• fib(n)fib(n-1) fib(n-2), ngt1.

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Problem 2

• Implement a recursive function fib(n) to compute
  Fibonacci numbers. Also write a short main
  function that prompts the user to enter the
  integer N, calls the function fib(N) and prints
  the value returned by the fib(N) function.
• int fib(int N)
• if(N 0) return 0
• else if(N 1) return 1
• else return fib(N-1) fib(N-2)

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Key Points

• Dynamically allocate memory
• li v0, 9 Memory allocation service
• li a0, ltintgt Allocate ltintgt bytes of
  mem.
• syscall
• move t0, v0 Move address of array to
  safety.
• Recursion
• self
• addi sp, sp, -4 Allocate stack space
• sw ra, 0(sp) Save old return
  address
• jal self Jump to self
• lw ra, 0(sp) Load old return address
• addi sp, sp, 4 Restore stack to old state