Only push a first instruction thread when on a potential start

There is no need to push threads for each codepoint when we know
they will fail as the current codepoint is not a start candidate.
This commit is contained in:
Maxime Coste 2024-03-16 11:22:01 +11:00
parent c3856ad3d9
commit ee364d911f

View File

@ -269,7 +269,7 @@ public:
{
if (search)
{
to_next_start(start, config, *start_desc);
start = find_next_start(start, config, *start_desc);
if (start == config.end) // If start_desc is not null, it means we consume at least one char
return false;
}
@ -479,6 +479,7 @@ private:
m_threads.push_current({first_inst, -1});
const auto& start_desc = forward ? m_program.forward_start_desc : m_program.backward_start_desc;
auto next_start = pos;
constexpr bool search = mode & RegexMode::Search;
constexpr bool any_match = mode & RegexMode::AnyMatch;
@ -513,38 +514,43 @@ private:
return m_found_match;
}
pos = next;
if (search and not m_found_match)
{
if (start_desc and m_threads.next_is_empty())
to_next_start(pos, config, *start_desc);
if (start_desc)
{
if (pos == next_start)
next_start = find_next_start(next, config, *start_desc);
if (m_threads.next_is_empty())
next = next_start;
}
if (not start_desc or next == next_start)
m_threads.push_next({first_inst, -1});
}
pos = next;
m_threads.swap_next();
}
}
static void to_next_start(Iterator& start, const ExecConfig& config, const StartDesc& start_desc)
static Iterator find_next_start(Iterator pos, const ExecConfig& config, const StartDesc& start_desc)
{
while (start != config.end)
while (pos != config.end)
{
static_assert(StartDesc::count <= 256, "start desc should be ascii only");
if constexpr (forward)
{
const unsigned char c = *start;
if (start_desc.map[c])
return;
++start;
if (start_desc.map[static_cast<unsigned char>(*pos)])
return pos;
++pos;
}
else
{
auto prev = utf8::previous(start, config.end);
const unsigned char c = *prev;
if (start_desc.map[c])
return;
start = prev;
auto prev = utf8::previous(pos, config.end);
if (start_desc.map[static_cast<unsigned char>(*prev)])
return pos;
pos = prev;
}
}
return pos;
}
bool lookaround(CompiledRegex::Param::Lookaround param, Iterator pos, const ExecConfig& config) const