Is there a more straightforward way to find $op_A where $op_A->sibling( $op_B ) when you have $op_B? I have B::Utils and B::Generate loaded. I am not using ->kids because it avoids null nodes but sometimes the node being searched from is a null node.

# Maybe find the opcode that thinks this opcode is its sibling by
# going to this opcode's parent and walking over the list of siblings
# until this one is reached. The previously visited opcode is the one
# we're after.
my $orig_reverse_sibling;
{
    my $prev;
    for ( my $sibling = $op->parent->first;
          $sibling;
          $sibling = $sibling->sibling )
    {
        if ( $sibling == $op )
        {
            $orig_reverse_sibling = $prev;
            last;
        }
        else
        {
            $prev = $sibling;
        }
    }
}

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In reply to Find opcode's reverse sibling? by diotalevi

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