xenia/home
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Regex: Make the Split op only take a single offset parameter

Browse Source 
Split now creates a new thread and keep the current one running, as
all of its uses are compatible with this behaviour, which enable a
more compact compiled code.
This commit is contained in:
Maxime Coste 2017-09-17 20:08:10 +09:00
parent f9dc6774b9
commit 4010c44fc0
1 changed files with 27 additions and 43 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

70
src/regex_impl.cc
View File

@ -77,8 +77,7 @@ private:
AstNodePtr res = make_ast_node(Op::Alternation); AstNodePtr res = make_ast_node(Op::Alternation);
res->children.push_back(std::move(node)); res->children.push_back(std::move(node));
while (pos != end and *pos == '|') res->children.push_back(disjunction(++pos, end));
res->children.push_back(disjunction(++pos, end));
return res; return res;
} }
@ -162,24 +161,21 @@ RegexProgram::Offset compile_node(Vector<char>& program, const AstNodePtr& node)
quantifier == Quantifier::RepeatOneOrMore; quantifier == Quantifier::RepeatOneOrMore;
}; };
auto alloc_offsets = [](Vector<char>& instructions, int count) { auto alloc_offset = [](Vector<char>& instructions) {
auto pos = instructions.size(); auto pos = instructions.size();
instructions.resize(instructions.size() + count * sizeof(RegexProgram::Offset)); instructions.resize(instructions.size() + sizeof(RegexProgram::Offset));
return pos; return pos;
}; };
auto get_offset = [](Vector<char>& instructions, RegexProgram::Offset base, int index = 0) { auto get_offset = [](Vector<char>& instructions, RegexProgram::Offset base) -> RegexProgram::Offset& {
return reinterpret_cast<RegexProgram::Offset*>(&instructions[base]) + index; return *reinterpret_cast<RegexProgram::Offset*>(&instructions[base]);
}; };
RegexProgram::Offset optional_offset = -1; RegexProgram::Offset optional_offset = -1;
if (allow_none(node->quantifier)) if (allow_none(node->quantifier))
{ {
program.push_back(RegexProgram::Split); program.push_back(RegexProgram::Split);
program.push_back(2); optional_offset = alloc_offset(program);
auto offsets = alloc_offsets(program, 2);
*get_offset(program, offsets) = program.size();
optional_offset = offsets;
} }
Vector<RegexProgram::Offset> goto_end_offsets; Vector<RegexProgram::Offset> goto_end_offsets;
@ -199,22 +195,19 @@ RegexProgram::Offset compile_node(Vector<char>& program, const AstNodePtr& node)
break; break;
case Op::Alternation: case Op::Alternation:
{ {
const auto count = node->children.size(); auto& children = node->children;
if (count > 255) kak_assert(children.size() == 2);
throw runtime_error{"More than 255 elements in an alternation is not supported"};
program.push_back(RegexProgram::Split); program.push_back(RegexProgram::Split);
program.push_back(count); auto offset = alloc_offset(program);
auto offsets = alloc_offsets(program, count);
auto& children = node->children; compile_node(program, children[0]);
for (int i = 0; i < children.size(); ++i) program.push_back(RegexProgram::Jump);
{ goto_end_offsets.push_back(alloc_offset(program));
auto child_pos = compile_node(program, children[i]);
*get_offset(program, offsets, i) = child_pos; auto right_pos = compile_node(program, children[1]);
// Jump to end after executing that children get_offset(program, offset) = right_pos;
program.push_back(RegexProgram::Jump);
goto_end_offsets.push_back(alloc_offsets(program, 1));
}
break; break;
} }
case Op::LineStart: case Op::LineStart:
@ -226,19 +219,16 @@ RegexProgram::Offset compile_node(Vector<char>& program, const AstNodePtr& node)
} }
for (auto& offset : goto_end_offsets) for (auto& offset : goto_end_offsets)
*get_offset(program, offset) = program.size(); get_offset(program, offset) = program.size();
if (is_repeat(node->quantifier)) if (is_repeat(node->quantifier))
{ {
program.push_back(RegexProgram::Split); program.push_back(RegexProgram::Split);
program.push_back(2); get_offset(program, alloc_offset(program)) = content_pos;
auto offsets = alloc_offsets(program, 2);
*get_offset(program, offsets, 0) = content_pos;
*get_offset(program, offsets, 1) = program.size();
} }
if (optional_offset != -1) if (optional_offset != -1)
*get_offset(program, optional_offset, 1) = program.size(); get_offset(program, optional_offset) = program.size();
return pos; return pos;
} }
@ -279,12 +269,8 @@ void dump(ConstArrayView<char> program)
break; break;
case RegexProgram::Split: case RegexProgram::Split:
{ {
int count = program[pos++]; printf("split %zd\n", *reinterpret_cast<const RegexProgram::Offset*>(&program[pos]));
printf("split ["); pos += sizeof(RegexProgram::Offset);
for (int i = 0; i < count; ++i)
printf("%zd%s", reinterpret_cast<const RegexProgram::Offset*>(&program[pos])[i],
(i == count - 1) ? "]\n" : ", ");
pos += count * sizeof(RegexProgram::Offset);
break; break;
} }
case RegexProgram::LineStart: case RegexProgram::LineStart:
@ -328,11 +314,8 @@ struct ThreadedExecutor
break; break;
case RegexProgram::Split: case RegexProgram::Split:
{ {
const int count = *inst++; m_threads.push_back(m_program.begin() + *reinterpret_cast<const RegexProgram::Offset*>(inst));
auto* offsets = reinterpret_cast<const RegexProgram::Offset*>(inst); inst += sizeof(RegexProgram::Offset);
for (int o = 1; o < count; ++o)
m_threads.push_back(m_program.begin() + offsets[o]);
inst = m_program.begin() + offsets[0];
break; break;
} }
case RegexProgram::LineStart: case RegexProgram::LineStart:
@ -410,14 +393,15 @@ auto test_regex = UnitTest{[]{
kak_assert(not exec.match(program, "")); kak_assert(not exec.match(program, ""));
} }
{ {
StringView re = "^(foo|qux)+(bar)?baz$"; StringView re = "^(foo|qux|baz)+(bar)?baz$";
auto program = RegexCompiler::compile(re.begin(), re.end()); auto program = RegexCompiler::compile(re.begin(), re.end());
RegexProgram::dump(program); RegexProgram::dump(program);
Exec exec{program}; Exec exec{program};
kak_assert(exec.match(program, "fooquxbarbaz")); kak_assert(exec.match(program, "fooquxbarbaz"));
kak_assert(not exec.match(program, "fooquxbarbaze"));
kak_assert(not exec.match(program, "quxbar")); kak_assert(not exec.match(program, "quxbar"));
kak_assert(not exec.match(program, "blahblah")); kak_assert(not exec.match(program, "blahblah"));
kak_assert(exec.match(program, "foobaz")); kak_assert(exec.match(program, "bazbaz"));
kak_assert(exec.match(program, "quxbaz")); kak_assert(exec.match(program, "quxbaz"));
} }
}}; }};