[LLVMdev] Should repetitive basic blocks be removed in the results of LoopBase::getExitBlocks()?

[xiaoming gu]

Hi, all. I'm using void LoopBase::getExitBlocks (SmallVectorImpl< BlockT *
> &ExitBlocks) const to get all
exit blocks for a loop. The problem I find with this API is that it returns
repetitive basic blocks in certain
situations. Should repetitive basic blocks be removed?

I have an example to show the problem. Following is the source code and the
CFG is enclosed.
int main()
{
  int i = rand()%10;

  while ( i < 20 )
    {
      i++;
      if ( i == 5)
return 21;
      if ( i == 9)
continue;
      else if ( i == 10)
break;
    }
  return i;
}

If you use getExitBlocks() to get the exit basic blocks for the loop, the
block "10" will show up twice in the
results.

Xiaoming
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