3. How DAG (directed acyclic graph) is different from syntax tree? a) Draw the DAG for...

  

Transcribed Image Text:

3. How DAG (directed acyclic graph) is different from syntax tree? a) Draw the DAG for given expression (a+b+c)+d+(a+b+c)-d+e b) Consider the following basic block- B10: S1=4x1 S2 = addr(A)-4 S3 S2[S1] S4 = 4 x 1 S5 addr(B) 4 S6 = S5[S4] S7 = S3 x S6 S8 = PROD + S7 PROD = S8 S9 = 1+1 1 = 59 If I 3. How DAG (directed acyclic graph) is different from syntax tree? a) Draw the DAG for given expression (a+b+c)+d+(a+b+c)-d+e b) Consider the following basic block- B10: S1=4x1 S2 = addr(A)-4 S3 S2[S1] S4 = 4 x 1 S5 addr(B) 4 S6 = S5[S4] S7 = S3 x S6 S8 = PROD + S7 PROD = S8 S9 = 1+1 1 = 59 If I