Description
Preamble
In this lab you’ll get some more experience writing ARC assembly. You’ll use logical and
arithmetic instructions in new ways, you’ll practice branching, and jumping to/returning
from subroutines.
Lab Description
1) (3 marks) SPARC supports floating point numbers and arithmetic. ARC, the subset of
SPARC we are using, does not. For this question, you will write an assembly program
that loads a 32-bit word assumed to be in encoded in the format of a single precision
floating point number (IEEE-754)
Your program will extract the exponent portion of the number and subtract the bias
(127 in this case). Load the register from memory location [flt], and store the
exponent result at location [exp]. Use the code snippet below to get started.
.begin
.org 2048
prog: ! Your assembly code here
flt: 0xc14a0000 ! 32-bit float to load
exp: 0x0 ! store exponent as integer here
.end
2) (6 marks) In class, we saw an example of iterative multiplication using branching. For
this question, you will implement iterative exponentiation. Base and exponent values
will be found in memory at labels base: and exp: respectively. Your program should
calculate the exponentiation and store the result at memory location res.
The base and exponent values are assumed to be positive integers. Other than this,
make no assumptions. See the program snippet below to get you started.
.begin
.org 2048
prog: ! Your assembly code here
base: 4 ! Here, we’re calculating
exp: 7 ! 4 to the power of 7 (47)
res: 0 ! Should be 16384 when program is done
.end
3) (6 marks) In similar fashion to iterative multiplication and exponentiation, you will
implement integer division using branching (think of how achieving division would
differ…). In the code below, operands are stored at labels x: and y:. The integer result
is to be stored at label quot: and the remainder is to be stored at label rem:.
.begin
.org 2048
prog: ! Your assembly code here
x: 8 ! Here, we’re dividing 8/3
y: 3
quot: 0 ! Integer result would be 2 in this case
rem: 0 ! remainder would also be 2
.end
ARC Specifics
Aside from the specifications indicated in each of the above questions, there are no
restrictions on how you structure your code, or which registers you use. Use as many
registers as you need, as much extra memory as you need, etc. As long as the input and
results are found at the correct labels, you’re all set.
Submission
Labs are to be submitted individually!
Submit a single file containing all three of your programs. An assembly .asm file is fine, as is
a plain text file (.txt) containing your code. No PDFs, no word documents, etc. This is to
make it easy for me to copy/paste your code into ARCTools. Make sure each program is
clearly separated in your submission. Upload this file, containing all three programs, on D2L
under Lab #2.
