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Fix find_end algorithm #597

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Merged
merged 2 commits into from
Apr 26, 2016
Merged

Fix find_end algorithm #597

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b18b5db
Fix test_find_end test
jszuppe Apr 24, 2016
940f379
Fix find_end algorithm
jszuppe Apr 24, 2016
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2 changes: 1 addition & 1 deletion include/boost/compute/algorithm/detail/search_all.hpp
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Original file line number Diff line number Diff line change
Expand Up @@ -48,7 +48,7 @@ class search_kernel : public meta_kernel

*this <<
"uint i = get_global_id(0);\n" <<
"uint i1 = i;\n" <<
"const uint i1 = i;\n" <<
"uint j;\n" <<
"for(j = 0; j<p_count; j++,i++)\n" <<
"{\n" <<
Expand Down
33 changes: 25 additions & 8 deletions include/boost/compute/algorithm/find_end.hpp
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Expand Up @@ -36,6 +36,7 @@ inline InputIterator find_end_helper(InputIterator first,
command_queue &queue)
{
typedef typename std::iterator_traits<InputIterator>::value_type value_type;
typedef typename std::iterator_traits<InputIterator>::difference_type difference_type;

size_t count = detail::iterator_range_size(first, last);
if(count == 0){
Expand Down Expand Up @@ -65,8 +66,13 @@ inline InputIterator find_end_helper(InputIterator first,
queue.enqueue_1d_range_kernel(kernel, 0, count, 0);

int result = static_cast<int>(index.read(queue));
if(result == -1) return last;
else return first + result;

if(result == -1){
return last;
}
else {
return first + static_cast<difference_type>(result);
}
}

} // end detail namespace
Expand All @@ -92,8 +98,13 @@ inline TextIterator find_end(TextIterator t_first,
command_queue &queue = system::default_queue())
{
const context &context = queue.get_context();
vector<uint_> matching_indices(detail::iterator_range_size(t_first, t_last),
context);

// there is no need to check if pattern starts at last n - 1 indices
vector<uint_> matching_indices(
detail::iterator_range_size(t_first, t_last)
+ 1 - detail::iterator_range_size(p_first, p_last),
context
);

detail::search_kernel<PatternIterator,
TextIterator,
Expand All @@ -105,10 +116,16 @@ inline TextIterator find_end(TextIterator t_first,
using boost::compute::_1;

vector<uint_>::iterator index =
detail::find_end_helper(matching_indices.begin(),
matching_indices.end(),
_1 == 1,
queue);
detail::find_end_helper(
matching_indices.begin(),
matching_indices.end(),
_1 == 1,
queue
);

// pattern was not found
if(index == matching_indices.end())
return t_last;

return t_first + detail::iterator_range_size(matching_indices.begin(), index);
}
Expand Down
20 changes: 10 additions & 10 deletions test/test_find_end.cpp
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Expand Up @@ -24,40 +24,40 @@ namespace bc = boost::compute;

BOOST_AUTO_TEST_CASE(find_end_int)
{
int data[] = {1, 4, 2, 6, 3, 2, 6, 3, 4, 6};
bc::int_ data[] = {1, 4, 2, 6, 3, 2, 6, 3, 4, 6};
bc::vector<bc::int_> vectort(data, data + 10, queue);

int datap[] = {2, 6};
bc::int_ datap[] = {2, 6};
bc::vector<bc::int_> vectorp(datap, datap + 2, queue);

bc::vector<bc::int_>::iterator iter =
bc::find_end(vectort.begin(), vectort.end(),
vectorp.begin(), vectorp.end(), queue);

BOOST_VERIFY(iter == vectort.begin() + 5);
BOOST_CHECK(iter == vectort.begin() + 5);

vectorp[1] = 9;
vectorp.insert(vectorp.begin() + 1, bc::int_(9), queue);

iter =
bc::find_end(vectort.begin(), vectort.end(),
vectorp.begin(), vectorp.end(), queue);
vectorp.begin(), vectorp.end(), queue);

BOOST_VERIFY(iter == vectort.begin() + 10);
BOOST_CHECK(iter == vectort.end());
}

BOOST_AUTO_TEST_CASE(find_end_string)
{
char text[] = "sdabababacabskjabacab";
bc::char_ text[] = "sdabababacabskjabacab";
bc::vector<bc::char_> vectort(text, text + 21, queue);

char pattern[] = "aba";
bc::char_ pattern[] = "aba";
bc::vector<bc::char_> vectorp(pattern, pattern + 3, queue);

bc::vector<bc::char_>::iterator iter =
bc::find_end(vectort.begin(), vectort.end(),
vectorp.begin(), vectorp.end(), queue);
vectorp.begin(), vectorp.end(), queue);

BOOST_VERIFY(iter == vectort.begin() + 15);
BOOST_CHECK(iter == (vectort.begin() + 15));
}

BOOST_AUTO_TEST_SUITE_END()