Martin Liška <mli...@suse.cz> writes:
> On 6/12/20 12:46 PM, Richard Sandiford wrote:
>> Martin Liška <mli...@suse.cz> writes:
>>> Hello.
>>>
>>> I'm working one extension of SLP which will allow to vectorize multiple
>>> BBs. This is a first step where I abstract _bb_vec_info::region_begin and
>>> _bb_vec_info::region end by providing an iterator.
>>
>> Nice.
>>
>>> diff --git a/gcc/tree-vectorizer.h b/gcc/tree-vectorizer.h
>>> index 6c830ad09f4..542d49402d2 100644
>>> --- a/gcc/tree-vectorizer.h
>>> +++ b/gcc/tree-vectorizer.h
>>> @@ -787,12 +787,46 @@ loop_vec_info_for_loop (class loop *loop)
>>> typedef class _bb_vec_info : public vec_info
>>> {
>>> public:
>>> + struct const_iterator
>>> + {
>>> + const_iterator (gimple_stmt_iterator _gsi): gsi (_gsi)
>>> + {
>>> + }
>>> +
>>> + const_iterator &
>>> + operator++ (int)
>>> + {
>>> + gsi_next (&gsi); return *this;
>>> + }
>>
>> Isn't this really operator++()?
>
> It is, but post-increment ++ operators have one integer argument (so that
> one can distinguish them from pre-increment operators:
> https://en.cppreference.com/w/cpp/language/operator_incdec)
Sure, but what I mean by:
>> I.e. it returns a reference to the
>> modified iterator instead of the value at the original iterator.
is that the above implements the semantics of a preincrement, not a
postincrement, so it should be operator++() rather than operator++(int).
In other words, the function (rightly) implements “++it” rather than “it++”.
With that fixed, it seems like a range-based for loop should work.
Thanks,
Richard
