(Last modified Thu Apr 17 22:42 2008)

Bring your work to class on the due date.  Class members will present parts of the analysis, and evaluate each other's work.

Calculate gen[S], kill[S], in[S], and out[S] for all the compound statements of the program below.

/*d1*/ i = m-1;
/*d2*/ j = n;
/*d3*/ a = u1;
       do
/*d4*/   i = i+1;
/*d5*/   j = j+1;
         if e1 then
/*d6*/     a = u2;
         else
/*d7*/     i = u3;
       while e2;

Use these compound statements (and any others you find necessary):

Sequence S1

/*d1*/ i = m-1;
/*d2*/ j = n;
/*d3*/ a = u1;

Sequence S2

/*d4*/   i = i+1;
/*d5*/   j = j+1;

Alternation S3

         if e1 then
/*d6*/     a = u2;
         else
/*d7*/     i = u3;

Iteration S4

       do
         /* S2 */
/*d4*/   i = i+1;
/*d5*/   j = j+1;
         /* S3 */
         if e1 then
/*d6*/     a = u2;
         else
/*d7*/     i = u3;
       while e2;

Sequence S5 (the entire program)

       /* S1 */
/*d1*/ i = m-1;
/*d2*/ j = n;
/*d3*/ a = u1;
       /* S4 */
       do
         /* S2 */
/*d4*/   i = i+1;
/*d5*/   j = j+1;
         /* S3 */
         if e1 then
/*d6*/     a = u2;
         else
/*d7*/     i = u3;
       while e2;

Thomas A. Alspaugh
Assistant Professor, Informatics Dept.
School of Information and Computer Sciences