Lab Exercise #8 -- SPARC Assembly Language

A. Examine the SPARC assembly language program which is contained in the file
named "~cse320/Labs/lab08.program.s" and answer the questions below.

1. Trace through the program, then complete the following to show the contents
of the indicated registers after the program executes.  Give a description
(variable name or algebraic term) for the contents of each register, and give
the value in the register as a decimal number and a hexadecimal number.  If
the program does not place a value into a given register, write "unknown" as
your description (and leave the value fields blank).

         description                 decimal value         hexadecimal value

   r16:  ________________________    __________________    __________________

   r17:  ________________________    __________________    __________________

   r18:  ________________________    __________________    __________________

   r19:  ________________________    __________________    __________________

   r20:  ________________________    __________________    __________________

   r21:  ________________________    __________________    __________________

   r22:  ________________________    __________________    __________________

   r23:  ________________________    __________________    __________________

   r24:  ________________________    __________________    __________________

   r25:  ________________________    __________________    __________________

   r26:  ________________________    __________________    __________________


2. What is the overall effect of the following pair of instructions?

   set      A, %r27
   ld       [%r27], %r16






3. What is the overall effect of the following pair of instructions?

   set      C, %r29
   st       %r21, [%r29]








4. What algebraic formula does this program compute?  Give your answer in
symbolic form (using "A" and "B").






5. Copy the source code into your account, then add calls to "memory" and
"iu_registers" to verify your answers.  See the source code in the file named
"Labs/lab08.sample.s" for examples of calls to those functions.

After revising the program, translate, link and execute the program using UNIX
commands similar to the following:

   <prompt> gcc your_file.s ~cse320/lib/reglib.o
   <prompt> a.out

Check your answers against the values displayed by the "reglib" functions.

6. Based on the values displayed by the "reglib" functions, what are the
addresses of each of the data items?  Give your answers in hexadecimal.

   A:  __________________

   B:  __________________

   C:  __________________



B. Design and implement the SPARC assembly language program specified below.

1. The program will compute the following function:

                   2             2
   f(x,y,z) = (x+3)  + 4xy - (2y)  + z

Assume that the values of "x", "y", and "z" will be supplied as data items in
the ".data" section of the program.

Use registers %r16 - %r29 for your intermediate results; do not use %r14,
%r15, %r30 or %r31 (those four registers are used by the run-time system).

Please note that you can re-use a particular register.  Once you no longer
need the value in that register, you can use it for a different purpose.

Suggestion:  copy the file containing your solution to Part A and edit the
resulting file to complete this experiment.

2. Use your program to compute the following values.

   f(2,6,3) =  ____________

   f(3,7,5) =  ____________

3. Compare the expected results (computed by hand) against the actual results
(displayed by the "reglib" functions) for both test cases.  Revise your
program, if necessary.