How many number of basic blocks will be there for this given snippet of code

Question

i=1,

j=1;

For this code how many different basic blocks are there?

Do we have to add begin and exit as two separate blocks?

In some test series for above two lines

i=1 is taken as one block and j=1 is taken as another block,whereas I have taken it as two blocks

This is not the full question of the actual test series I have just focussed on the part which I have a doubt on

Edit 1 based on comment of the question

pseudo code is this

for i=1 to 10

  for j=1 to 10

    a[i,j]=10

end

end

for i=1 to 10

    some operation

end

I think this question is there in Compiler Design by Venkatesh under Code Optimization but isn’t code optimization not part of the syllabus this year?

Comments

I think it should be taken as a single block..

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without getting the full question its really tough to say that why they have used tow separate blocks for above two lines. its better to provide full question

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If the goto points to some specific initialization then it should be in a separate block?

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@sripo target of any goto is another block

 

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@Shubhgupta can u plz tell whether we should use start and end blocks or not??

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@anjali007, yes we need to always consider entry and exit block in data flow graph.

"an ENTRY node, which represents the starting point of the graph, and an EXIT node to which all exits out of the graph go."

@sripo, because in the loop we have condition and every condition will have goto statement so that's why in this code they are using 2 separate block because target of first loop is second loop and target of second loop is 3rd statement.

If the goto points to some specific initialization then it should be in a separate block?

As anjali said, target of any goto is a leader and statement that follows goto is also a leader.

Moreover, I think code optimization is not part of the syllabus.

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@Shubhgupta thanks..:)

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I think one of the blocks point to j=1 in the goto label hence j=1 is a separate block.

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yes