mirror of
https://github.com/RGBCube/serenity
synced 2025-10-31 04:52:45 +00:00
387df06385
The initial `ForkStay` is only needed if the looping block has a following block, if there's no following block or the following block does not attempt to match anything, we should not insert the ForkStay, otherwise we would be rewriting `a+` as `a*` by allowing the 'end' to be executed. Fixes #10952.
666 lines
29 KiB
C++
666 lines
29 KiB
C++
/*
|
|
* Copyright (c) 2021, Ali Mohammad Pur <mpfard@serenityos.org>
|
|
*
|
|
* SPDX-License-Identifier: BSD-2-Clause
|
|
*/
|
|
|
|
#include <AK/QuickSort.h>
|
|
#include <AK/RedBlackTree.h>
|
|
#include <AK/Stack.h>
|
|
#include <LibRegex/Regex.h>
|
|
#include <LibRegex/RegexBytecodeStreamOptimizer.h>
|
|
|
|
namespace regex {
|
|
|
|
using Detail::Block;
|
|
|
|
template<typename Parser>
|
|
void Regex<Parser>::run_optimization_passes()
|
|
{
|
|
parser_result.bytecode.flatten();
|
|
|
|
// Rewrite fork loops as atomic groups
|
|
// e.g. a*b -> (ATOMIC a*)b
|
|
attempt_rewrite_loops_as_atomic_groups(split_basic_blocks());
|
|
|
|
parser_result.bytecode.flatten();
|
|
}
|
|
|
|
template<typename Parser>
|
|
typename Regex<Parser>::BasicBlockList Regex<Parser>::split_basic_blocks()
|
|
{
|
|
BasicBlockList block_boundaries;
|
|
auto& bytecode = parser_result.bytecode;
|
|
size_t end_of_last_block = 0;
|
|
|
|
MatchState state;
|
|
state.instruction_position = 0;
|
|
auto check_jump = [&]<typename T>(OpCode const& opcode) {
|
|
auto& op = static_cast<T const&>(opcode);
|
|
ssize_t jump_offset = op.size() + op.offset();
|
|
if (jump_offset >= 0) {
|
|
block_boundaries.append({ end_of_last_block, state.instruction_position });
|
|
end_of_last_block = state.instruction_position + opcode.size();
|
|
} else {
|
|
// This op jumps back, see if that's within this "block".
|
|
if (jump_offset + state.instruction_position > end_of_last_block) {
|
|
// Split the block!
|
|
block_boundaries.append({ end_of_last_block, jump_offset + state.instruction_position });
|
|
block_boundaries.append({ jump_offset + state.instruction_position, state.instruction_position });
|
|
end_of_last_block = state.instruction_position + opcode.size();
|
|
} else {
|
|
// Nope, it's just a jump to another block
|
|
block_boundaries.append({ end_of_last_block, state.instruction_position });
|
|
end_of_last_block = state.instruction_position + opcode.size();
|
|
}
|
|
}
|
|
};
|
|
for (;;) {
|
|
auto& opcode = bytecode.get_opcode(state);
|
|
|
|
switch (opcode.opcode_id()) {
|
|
case OpCodeId::Jump:
|
|
check_jump.template operator()<OpCode_Jump>(opcode);
|
|
break;
|
|
case OpCodeId::JumpNonEmpty:
|
|
check_jump.template operator()<OpCode_JumpNonEmpty>(opcode);
|
|
break;
|
|
case OpCodeId::ForkJump:
|
|
check_jump.template operator()<OpCode_ForkJump>(opcode);
|
|
break;
|
|
case OpCodeId::ForkStay:
|
|
check_jump.template operator()<OpCode_ForkStay>(opcode);
|
|
break;
|
|
case OpCodeId::FailForks:
|
|
block_boundaries.append({ end_of_last_block, state.instruction_position });
|
|
end_of_last_block = state.instruction_position + opcode.size();
|
|
break;
|
|
case OpCodeId::Repeat: {
|
|
// Repeat produces two blocks, one containing its repeated expr, and one after that.
|
|
auto repeat_start = state.instruction_position - static_cast<OpCode_Repeat const&>(opcode).offset();
|
|
if (repeat_start > end_of_last_block)
|
|
block_boundaries.append({ end_of_last_block, repeat_start });
|
|
block_boundaries.append({ repeat_start, state.instruction_position });
|
|
end_of_last_block = state.instruction_position + opcode.size();
|
|
break;
|
|
}
|
|
default:
|
|
break;
|
|
}
|
|
|
|
auto next_ip = state.instruction_position + opcode.size();
|
|
if (next_ip < bytecode.size())
|
|
state.instruction_position = next_ip;
|
|
else
|
|
break;
|
|
}
|
|
|
|
if (end_of_last_block < bytecode.size())
|
|
block_boundaries.append({ end_of_last_block, bytecode.size() });
|
|
|
|
quick_sort(block_boundaries, [](auto& a, auto& b) { return a.start < b.start; });
|
|
|
|
return block_boundaries;
|
|
}
|
|
|
|
enum class AtomicRewritePreconditionResult {
|
|
SatisfiedWithProperHeader,
|
|
SatisfiedWithEmptyHeader,
|
|
NotSatisfied,
|
|
};
|
|
static AtomicRewritePreconditionResult block_satisfies_atomic_rewrite_precondition(ByteCode const& bytecode, Block const& repeated_block, Block const& following_block)
|
|
{
|
|
Vector<Vector<CompareTypeAndValuePair>> repeated_values;
|
|
HashTable<size_t> active_capture_groups;
|
|
MatchState state;
|
|
for (state.instruction_position = repeated_block.start; state.instruction_position < repeated_block.end;) {
|
|
auto& opcode = bytecode.get_opcode(state);
|
|
switch (opcode.opcode_id()) {
|
|
case OpCodeId::Compare: {
|
|
auto compares = static_cast<OpCode_Compare const&>(opcode).flat_compares();
|
|
if (repeated_values.is_empty() && any_of(compares, [](auto& compare) { return compare.type == CharacterCompareType::AnyChar; }))
|
|
return AtomicRewritePreconditionResult::NotSatisfied;
|
|
repeated_values.append(move(compares));
|
|
break;
|
|
}
|
|
case OpCodeId::CheckBegin:
|
|
case OpCodeId::CheckEnd:
|
|
if (repeated_values.is_empty())
|
|
return AtomicRewritePreconditionResult::SatisfiedWithProperHeader;
|
|
break;
|
|
case OpCodeId::CheckBoundary:
|
|
// FIXME: What should we do with these? for now, let's fail.
|
|
return AtomicRewritePreconditionResult::NotSatisfied;
|
|
case OpCodeId::Restore:
|
|
case OpCodeId::GoBack:
|
|
return AtomicRewritePreconditionResult::NotSatisfied;
|
|
case OpCodeId::SaveRightCaptureGroup:
|
|
active_capture_groups.set(static_cast<OpCode_SaveRightCaptureGroup const&>(opcode).id());
|
|
break;
|
|
case OpCodeId::SaveLeftCaptureGroup:
|
|
active_capture_groups.set(static_cast<OpCode_SaveLeftCaptureGroup const&>(opcode).id());
|
|
break;
|
|
default:
|
|
break;
|
|
}
|
|
|
|
state.instruction_position += opcode.size();
|
|
}
|
|
dbgln_if(REGEX_DEBUG, "Found {} entries in reference", repeated_values.size());
|
|
dbgln_if(REGEX_DEBUG, "Found {} active capture groups", active_capture_groups.size());
|
|
|
|
bool following_block_has_at_least_one_compare = false;
|
|
// Find the first compare in the following block, it must NOT match any of the values in `repeated_values'.
|
|
for (state.instruction_position = following_block.start; state.instruction_position < following_block.end;) {
|
|
auto& opcode = bytecode.get_opcode(state);
|
|
switch (opcode.opcode_id()) {
|
|
// Note: These have to exist since we're effectively repeating the following block as well
|
|
case OpCodeId::SaveRightCaptureGroup:
|
|
active_capture_groups.set(static_cast<OpCode_SaveRightCaptureGroup const&>(opcode).id());
|
|
break;
|
|
case OpCodeId::SaveLeftCaptureGroup:
|
|
active_capture_groups.set(static_cast<OpCode_SaveLeftCaptureGroup const&>(opcode).id());
|
|
break;
|
|
case OpCodeId::Compare: {
|
|
following_block_has_at_least_one_compare = true;
|
|
// We found a compare, let's see what it has.
|
|
auto compares = static_cast<OpCode_Compare const&>(opcode).flat_compares();
|
|
if (compares.is_empty())
|
|
break;
|
|
|
|
if (any_of(compares, [&](auto& compare) {
|
|
return compare.type == CharacterCompareType::AnyChar
|
|
|| (compare.type == CharacterCompareType::Reference && active_capture_groups.contains(compare.value));
|
|
}))
|
|
return AtomicRewritePreconditionResult::NotSatisfied;
|
|
|
|
for (auto& repeated_value : repeated_values) {
|
|
// FIXME: This is too naive!
|
|
if (any_of(repeated_value, [](auto& compare) { return compare.type == CharacterCompareType::AnyChar; }))
|
|
return AtomicRewritePreconditionResult::NotSatisfied;
|
|
|
|
for (auto& repeated_compare : repeated_value) {
|
|
// FIXME: This is too naive! it will miss _tons_ of cases since it doesn't check ranges!
|
|
if (any_of(compares, [&](auto& compare) { return compare.type == repeated_compare.type && compare.value == repeated_compare.value; }))
|
|
return AtomicRewritePreconditionResult::NotSatisfied;
|
|
}
|
|
}
|
|
return AtomicRewritePreconditionResult::SatisfiedWithProperHeader;
|
|
}
|
|
case OpCodeId::CheckBegin:
|
|
case OpCodeId::CheckEnd:
|
|
return AtomicRewritePreconditionResult::SatisfiedWithProperHeader; // Nothing can match the end!
|
|
case OpCodeId::CheckBoundary:
|
|
// FIXME: What should we do with these? For now, consider them a failure.
|
|
return AtomicRewritePreconditionResult::NotSatisfied;
|
|
default:
|
|
break;
|
|
}
|
|
|
|
state.instruction_position += opcode.size();
|
|
}
|
|
|
|
if (following_block_has_at_least_one_compare)
|
|
return AtomicRewritePreconditionResult::SatisfiedWithProperHeader;
|
|
return AtomicRewritePreconditionResult::SatisfiedWithEmptyHeader;
|
|
}
|
|
|
|
template<typename Parser>
|
|
void Regex<Parser>::attempt_rewrite_loops_as_atomic_groups(BasicBlockList const& basic_blocks)
|
|
{
|
|
auto& bytecode = parser_result.bytecode;
|
|
if constexpr (REGEX_DEBUG) {
|
|
RegexDebug dbg;
|
|
dbg.print_bytecode(*this);
|
|
for (auto& block : basic_blocks)
|
|
dbgln("block from {} to {}", block.start, block.end);
|
|
}
|
|
|
|
// A pattern such as:
|
|
// bb0 | RE0
|
|
// | ForkX bb0
|
|
// -------------------------
|
|
// bb1 | RE1
|
|
// can be rewritten as:
|
|
// loop.hdr | ForkStay bb1 (if RE1 matches _something_, empty otherwise)
|
|
// -------------------------
|
|
// bb0 | RE0
|
|
// | ForkReplaceX bb0
|
|
// -------------------------
|
|
// bb1 | RE1
|
|
// provided that first(RE1) not-in end(RE0), which is to say
|
|
// that RE1 cannot start with whatever RE0 has matched (ever).
|
|
//
|
|
// Alternatively, a second form of this pattern can also occur:
|
|
// bb0 | *
|
|
// | ForkX bb2
|
|
// ------------------------
|
|
// bb1 | RE0
|
|
// | Jump bb0
|
|
// ------------------------
|
|
// bb2 | RE1
|
|
// which can be transformed (with the same preconditions) to:
|
|
// bb0 | *
|
|
// | ForkReplaceX bb2
|
|
// ------------------------
|
|
// bb1 | RE0
|
|
// | Jump bb0
|
|
// ------------------------
|
|
// bb2 | RE1
|
|
|
|
enum class AlternateForm {
|
|
DirectLoopWithoutHeader, // loop without proper header, a block forking to itself. i.e. the first form.
|
|
DirectLoopWithoutHeaderAndEmptyFollow, // loop without proper header, a block forking to itself. i.e. the first form but with RE1 being empty.
|
|
DirectLoopWithHeader, // loop with proper header, i.e. the second form.
|
|
};
|
|
struct CandidateBlock {
|
|
Block forking_block;
|
|
Optional<Block> new_target_block;
|
|
AlternateForm form;
|
|
};
|
|
Vector<CandidateBlock> candidate_blocks;
|
|
|
|
auto is_an_eligible_jump = [](OpCode const& opcode, size_t ip, size_t block_start, AlternateForm alternate_form) {
|
|
switch (opcode.opcode_id()) {
|
|
case OpCodeId::JumpNonEmpty: {
|
|
auto& op = static_cast<OpCode_JumpNonEmpty const&>(opcode);
|
|
auto form = op.form();
|
|
if (form != OpCodeId::Jump && alternate_form == AlternateForm::DirectLoopWithHeader)
|
|
return false;
|
|
if (form != OpCodeId::ForkJump && form != OpCodeId::ForkStay && alternate_form == AlternateForm::DirectLoopWithoutHeader)
|
|
return false;
|
|
return op.offset() + ip + opcode.size() == block_start;
|
|
}
|
|
case OpCodeId::ForkJump:
|
|
if (alternate_form == AlternateForm::DirectLoopWithHeader)
|
|
return false;
|
|
return static_cast<OpCode_ForkJump const&>(opcode).offset() + ip + opcode.size() == block_start;
|
|
case OpCodeId::ForkStay:
|
|
if (alternate_form == AlternateForm::DirectLoopWithHeader)
|
|
return false;
|
|
return static_cast<OpCode_ForkStay const&>(opcode).offset() + ip + opcode.size() == block_start;
|
|
case OpCodeId::Jump:
|
|
// Infinite loop does *not* produce forks.
|
|
if (alternate_form == AlternateForm::DirectLoopWithoutHeader)
|
|
return false;
|
|
if (alternate_form == AlternateForm::DirectLoopWithHeader)
|
|
return static_cast<OpCode_Jump const&>(opcode).offset() + ip + opcode.size() == block_start;
|
|
VERIFY_NOT_REACHED();
|
|
default:
|
|
return false;
|
|
}
|
|
};
|
|
for (size_t i = 0; i < basic_blocks.size(); ++i) {
|
|
auto forking_block = basic_blocks[i];
|
|
Optional<Block> fork_fallback_block;
|
|
if (i + 1 < basic_blocks.size())
|
|
fork_fallback_block = basic_blocks[i + 1];
|
|
MatchState state;
|
|
// Check if the last instruction in this block is a jump to the block itself:
|
|
{
|
|
state.instruction_position = forking_block.end;
|
|
auto& opcode = bytecode.get_opcode(state);
|
|
if (is_an_eligible_jump(opcode, state.instruction_position, forking_block.start, AlternateForm::DirectLoopWithoutHeader)) {
|
|
// We've found RE0 (and RE1 is just the following block, if any), let's see if the precondition applies.
|
|
// if RE1 is empty, there's no first(RE1), so this is an automatic pass.
|
|
if (!fork_fallback_block.has_value() || fork_fallback_block->end == fork_fallback_block->start) {
|
|
candidate_blocks.append({ forking_block, fork_fallback_block, AlternateForm::DirectLoopWithoutHeader });
|
|
break;
|
|
}
|
|
|
|
auto precondition = block_satisfies_atomic_rewrite_precondition(bytecode, forking_block, *fork_fallback_block);
|
|
if (precondition == AtomicRewritePreconditionResult::SatisfiedWithProperHeader) {
|
|
candidate_blocks.append({ forking_block, fork_fallback_block, AlternateForm::DirectLoopWithoutHeader });
|
|
break;
|
|
}
|
|
if (precondition == AtomicRewritePreconditionResult::SatisfiedWithEmptyHeader) {
|
|
candidate_blocks.append({ forking_block, fork_fallback_block, AlternateForm::DirectLoopWithoutHeaderAndEmptyFollow });
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
// Check if the last instruction in the last block is a direct jump to this block
|
|
if (fork_fallback_block.has_value()) {
|
|
state.instruction_position = fork_fallback_block->end;
|
|
auto& opcode = bytecode.get_opcode(state);
|
|
if (is_an_eligible_jump(opcode, state.instruction_position, forking_block.start, AlternateForm::DirectLoopWithHeader)) {
|
|
// We've found bb1 and bb0, let's just make sure that bb0 forks to bb2.
|
|
state.instruction_position = forking_block.end;
|
|
auto& opcode = bytecode.get_opcode(state);
|
|
if (opcode.opcode_id() == OpCodeId::ForkJump || opcode.opcode_id() == OpCodeId::ForkStay) {
|
|
Optional<Block> block_following_fork_fallback;
|
|
if (i + 2 < basic_blocks.size())
|
|
block_following_fork_fallback = basic_blocks[i + 2];
|
|
if (!block_following_fork_fallback.has_value()
|
|
|| block_satisfies_atomic_rewrite_precondition(bytecode, *fork_fallback_block, *block_following_fork_fallback) != AtomicRewritePreconditionResult::NotSatisfied) {
|
|
candidate_blocks.append({ forking_block, {}, AlternateForm::DirectLoopWithHeader });
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
dbgln_if(REGEX_DEBUG, "Found {} candidate blocks", candidate_blocks.size());
|
|
if (candidate_blocks.is_empty()) {
|
|
dbgln_if(REGEX_DEBUG, "Failed to find anything for {}", pattern_value);
|
|
return;
|
|
}
|
|
|
|
RedBlackTree<size_t, size_t> needed_patches;
|
|
|
|
// Reverse the blocks, so we can patch the bytecode without messing with the latter patches.
|
|
quick_sort(candidate_blocks, [](auto& a, auto& b) { return b.forking_block.start > a.forking_block.start; });
|
|
for (auto& candidate : candidate_blocks) {
|
|
// Note that both forms share a ForkReplace patch in forking_block.
|
|
// Patch the ForkX in forking_block to be a ForkReplaceX instead.
|
|
auto& opcode_id = bytecode[candidate.forking_block.end];
|
|
if (opcode_id == (ByteCodeValueType)OpCodeId::ForkStay) {
|
|
opcode_id = (ByteCodeValueType)OpCodeId::ForkReplaceStay;
|
|
} else if (opcode_id == (ByteCodeValueType)OpCodeId::ForkJump) {
|
|
opcode_id = (ByteCodeValueType)OpCodeId::ForkReplaceJump;
|
|
} else if (opcode_id == (ByteCodeValueType)OpCodeId::JumpNonEmpty) {
|
|
auto& jump_opcode_id = bytecode[candidate.forking_block.end + 3];
|
|
if (jump_opcode_id == (ByteCodeValueType)OpCodeId::ForkStay)
|
|
jump_opcode_id = (ByteCodeValueType)OpCodeId::ForkReplaceStay;
|
|
else if (jump_opcode_id == (ByteCodeValueType)OpCodeId::ForkJump)
|
|
jump_opcode_id = (ByteCodeValueType)OpCodeId::ForkReplaceJump;
|
|
else
|
|
VERIFY_NOT_REACHED();
|
|
} else {
|
|
VERIFY_NOT_REACHED();
|
|
}
|
|
|
|
if (candidate.form == AlternateForm::DirectLoopWithoutHeader) {
|
|
if (candidate.new_target_block.has_value()) {
|
|
// Insert a fork-stay targeted at the second block.
|
|
bytecode.insert(candidate.forking_block.start, (ByteCodeValueType)OpCodeId::ForkStay);
|
|
bytecode.insert(candidate.forking_block.start + 1, candidate.new_target_block->start - candidate.forking_block.start);
|
|
needed_patches.insert(candidate.forking_block.start, 2u);
|
|
}
|
|
}
|
|
}
|
|
|
|
if (!needed_patches.is_empty()) {
|
|
MatchState state;
|
|
state.instruction_position = 0;
|
|
struct Patch {
|
|
ssize_t value;
|
|
size_t offset;
|
|
bool should_negate { false };
|
|
};
|
|
for (;;) {
|
|
if (state.instruction_position >= bytecode.size())
|
|
break;
|
|
|
|
auto& opcode = bytecode.get_opcode(state);
|
|
Stack<Patch, 2> patch_points;
|
|
|
|
switch (opcode.opcode_id()) {
|
|
case OpCodeId::Jump:
|
|
patch_points.push({ static_cast<OpCode_Jump const&>(opcode).offset(), state.instruction_position + 1 });
|
|
break;
|
|
case OpCodeId::JumpNonEmpty:
|
|
patch_points.push({ static_cast<OpCode_JumpNonEmpty const&>(opcode).offset(), state.instruction_position + 1 });
|
|
patch_points.push({ static_cast<OpCode_JumpNonEmpty const&>(opcode).checkpoint(), state.instruction_position + 2 });
|
|
break;
|
|
case OpCodeId::ForkJump:
|
|
patch_points.push({ static_cast<OpCode_ForkJump const&>(opcode).offset(), state.instruction_position + 1 });
|
|
break;
|
|
case OpCodeId::ForkStay:
|
|
patch_points.push({ static_cast<OpCode_ForkStay const&>(opcode).offset(), state.instruction_position + 1 });
|
|
break;
|
|
case OpCodeId::Repeat:
|
|
patch_points.push({ -(ssize_t) static_cast<OpCode_Repeat const&>(opcode).offset(), state.instruction_position + 1, true });
|
|
break;
|
|
default:
|
|
break;
|
|
}
|
|
|
|
while (!patch_points.is_empty()) {
|
|
auto& patch_point = patch_points.top();
|
|
auto target_offset = patch_point.value + state.instruction_position + opcode.size();
|
|
|
|
constexpr auto do_patch = [](auto& patch_it, auto& patch_point, auto& target_offset, auto& bytecode, auto ip) {
|
|
if (patch_it.key() == ip)
|
|
return;
|
|
|
|
if (patch_point.value < 0 && target_offset < patch_it.key() && ip > patch_it.key())
|
|
bytecode[patch_point.offset] += (patch_point.should_negate ? 1 : -1) * (*patch_it);
|
|
else if (patch_point.value > 0 && target_offset > patch_it.key() && ip < patch_it.key())
|
|
bytecode[patch_point.offset] += (patch_point.should_negate ? -1 : 1) * (*patch_it);
|
|
};
|
|
|
|
if (auto patch_it = needed_patches.find_largest_not_above_iterator(target_offset); !patch_it.is_end())
|
|
do_patch(patch_it, patch_point, target_offset, bytecode, state.instruction_position);
|
|
else if (auto patch_it = needed_patches.find_largest_not_above_iterator(state.instruction_position); !patch_it.is_end())
|
|
do_patch(patch_it, patch_point, target_offset, bytecode, state.instruction_position);
|
|
|
|
patch_points.pop();
|
|
}
|
|
|
|
state.instruction_position += opcode.size();
|
|
}
|
|
}
|
|
|
|
if constexpr (REGEX_DEBUG) {
|
|
warnln("Transformed to:");
|
|
RegexDebug dbg;
|
|
dbg.print_bytecode(*this);
|
|
}
|
|
}
|
|
|
|
void Optimizer::append_alternation(ByteCode& target, ByteCode&& left, ByteCode&& right)
|
|
{
|
|
auto left_is_empty = left.is_empty();
|
|
auto right_is_empty = right.is_empty();
|
|
if (left_is_empty || right_is_empty) {
|
|
if (left_is_empty && right_is_empty)
|
|
return;
|
|
|
|
// ForkJump right (+ left.size() + 2 + right.size())
|
|
// (left)
|
|
// Jump end (+ right.size())
|
|
// (right)
|
|
// LABEL end
|
|
target.append(static_cast<ByteCodeValueType>(OpCodeId::ForkJump));
|
|
target.append(left.size() + 2 + right.size());
|
|
target.extend(move(left));
|
|
target.append(static_cast<ByteCodeValueType>(OpCodeId::Jump));
|
|
target.append(right.size());
|
|
target.extend(move(right));
|
|
return;
|
|
}
|
|
|
|
size_t left_skip = 0;
|
|
MatchState state;
|
|
for (state.instruction_position = 0; state.instruction_position < left.size() && state.instruction_position < right.size();) {
|
|
auto left_size = left.get_opcode(state).size();
|
|
auto right_size = right.get_opcode(state).size();
|
|
if (left_size != right_size)
|
|
break;
|
|
|
|
if (left.spans().slice(state.instruction_position, left_size) == right.spans().slice(state.instruction_position, right_size))
|
|
left_skip = state.instruction_position + left_size;
|
|
else
|
|
break;
|
|
|
|
state.instruction_position += left_size;
|
|
}
|
|
|
|
dbgln_if(REGEX_DEBUG, "Skipping {}/{} bytecode entries from {}/{}", left_skip, 0, left.size(), right.size());
|
|
|
|
if (left_skip) {
|
|
target.extend(left.release_slice(0, left_skip));
|
|
right = right.release_slice(left_skip);
|
|
}
|
|
|
|
auto left_size = left.size();
|
|
|
|
target.empend(static_cast<ByteCodeValueType>(OpCodeId::ForkJump));
|
|
target.empend(right.size() + (left_size ? 2 : 0)); // Jump to the _ALT label
|
|
|
|
target.extend(move(right));
|
|
|
|
if (left_size != 0) {
|
|
target.empend(static_cast<ByteCodeValueType>(OpCodeId::Jump));
|
|
target.empend(left.size()); // Jump to the _END label
|
|
}
|
|
|
|
// LABEL _ALT = bytecode.size() + 2
|
|
|
|
target.extend(move(left));
|
|
|
|
// LABEL _END = alterantive_bytecode.size
|
|
}
|
|
|
|
enum class LookupTableInsertionOutcome {
|
|
Successful,
|
|
ReplaceWithAnyChar,
|
|
TemporaryInversionNeeded,
|
|
PermanentInversionNeeded,
|
|
CannotPlaceInTable,
|
|
};
|
|
static LookupTableInsertionOutcome insert_into_lookup_table(RedBlackTree<ByteCodeValueType, CharRange>& table, CompareTypeAndValuePair pair)
|
|
{
|
|
switch (pair.type) {
|
|
case CharacterCompareType::Inverse:
|
|
return LookupTableInsertionOutcome::PermanentInversionNeeded;
|
|
case CharacterCompareType::TemporaryInverse:
|
|
return LookupTableInsertionOutcome::TemporaryInversionNeeded;
|
|
case CharacterCompareType::AnyChar:
|
|
return LookupTableInsertionOutcome::ReplaceWithAnyChar;
|
|
case CharacterCompareType::CharClass:
|
|
return LookupTableInsertionOutcome::CannotPlaceInTable;
|
|
case CharacterCompareType::Char:
|
|
table.insert(pair.value, { (u32)pair.value, (u32)pair.value });
|
|
break;
|
|
case CharacterCompareType::CharRange: {
|
|
CharRange range { pair.value };
|
|
table.insert(range.from, range);
|
|
break;
|
|
}
|
|
case CharacterCompareType::Reference:
|
|
case CharacterCompareType::Property:
|
|
case CharacterCompareType::GeneralCategory:
|
|
case CharacterCompareType::Script:
|
|
case CharacterCompareType::ScriptExtension:
|
|
return LookupTableInsertionOutcome::CannotPlaceInTable;
|
|
case CharacterCompareType::Undefined:
|
|
case CharacterCompareType::RangeExpressionDummy:
|
|
case CharacterCompareType::String:
|
|
case CharacterCompareType::LookupTable:
|
|
VERIFY_NOT_REACHED();
|
|
}
|
|
|
|
return LookupTableInsertionOutcome::Successful;
|
|
}
|
|
|
|
void Optimizer::append_character_class(ByteCode& target, Vector<CompareTypeAndValuePair>&& pairs)
|
|
{
|
|
ByteCode arguments;
|
|
size_t argument_count = 0;
|
|
|
|
if (pairs.size() <= 1) {
|
|
for (auto& pair : pairs) {
|
|
arguments.append(to_underlying(pair.type));
|
|
if (pair.type != CharacterCompareType::AnyChar && pair.type != CharacterCompareType::TemporaryInverse && pair.type != CharacterCompareType::Inverse)
|
|
arguments.append(pair.value);
|
|
++argument_count;
|
|
}
|
|
} else {
|
|
RedBlackTree<ByteCodeValueType, CharRange> table;
|
|
RedBlackTree<ByteCodeValueType, CharRange> inverted_table;
|
|
auto* current_table = &table;
|
|
auto* current_inverted_table = &inverted_table;
|
|
bool invert_for_next_iteration = false;
|
|
bool is_currently_inverted = false;
|
|
|
|
for (auto& value : pairs) {
|
|
auto should_invert_after_this_iteration = invert_for_next_iteration;
|
|
invert_for_next_iteration = false;
|
|
|
|
auto insertion_result = insert_into_lookup_table(*current_table, value);
|
|
switch (insertion_result) {
|
|
case LookupTableInsertionOutcome::Successful:
|
|
break;
|
|
case LookupTableInsertionOutcome::ReplaceWithAnyChar: {
|
|
table.clear();
|
|
inverted_table.clear();
|
|
arguments.append(to_underlying(CharacterCompareType::AnyChar));
|
|
++argument_count;
|
|
break;
|
|
}
|
|
case LookupTableInsertionOutcome::TemporaryInversionNeeded:
|
|
swap(current_table, current_inverted_table);
|
|
invert_for_next_iteration = true;
|
|
is_currently_inverted = !is_currently_inverted;
|
|
break;
|
|
case LookupTableInsertionOutcome::PermanentInversionNeeded:
|
|
swap(current_table, current_inverted_table);
|
|
is_currently_inverted = !is_currently_inverted;
|
|
break;
|
|
case LookupTableInsertionOutcome::CannotPlaceInTable:
|
|
if (is_currently_inverted) {
|
|
arguments.append(to_underlying(CharacterCompareType::TemporaryInverse));
|
|
++argument_count;
|
|
}
|
|
arguments.append(to_underlying(value.type));
|
|
arguments.append(value.value);
|
|
++argument_count;
|
|
break;
|
|
}
|
|
|
|
if (should_invert_after_this_iteration) {
|
|
swap(current_table, current_inverted_table);
|
|
is_currently_inverted = !is_currently_inverted;
|
|
}
|
|
}
|
|
auto append_table = [&](auto& table) {
|
|
++argument_count;
|
|
arguments.append(to_underlying(CharacterCompareType::LookupTable));
|
|
auto size_index = arguments.size();
|
|
arguments.append(0);
|
|
Optional<CharRange> active_range;
|
|
size_t range_count = 0;
|
|
for (auto& range : table) {
|
|
if (!active_range.has_value()) {
|
|
active_range = range;
|
|
continue;
|
|
}
|
|
|
|
if (range.from <= active_range->to + 1 && range.to + 1 >= active_range->from) {
|
|
active_range = CharRange { min(range.from, active_range->from), max(range.to, active_range->to) };
|
|
} else {
|
|
++range_count;
|
|
arguments.append(active_range.release_value());
|
|
active_range = range;
|
|
}
|
|
}
|
|
if (active_range.has_value()) {
|
|
++range_count;
|
|
arguments.append(active_range.release_value());
|
|
}
|
|
arguments[size_index] = range_count;
|
|
};
|
|
|
|
if (!table.is_empty())
|
|
append_table(table);
|
|
|
|
if (!inverted_table.is_empty()) {
|
|
++argument_count;
|
|
arguments.append(to_underlying(CharacterCompareType::TemporaryInverse));
|
|
append_table(inverted_table);
|
|
}
|
|
}
|
|
|
|
target.empend(static_cast<ByteCodeValueType>(OpCodeId::Compare));
|
|
target.empend(argument_count); // number of arguments
|
|
target.empend(arguments.size()); // size of arguments
|
|
target.extend(move(arguments));
|
|
}
|
|
|
|
template void Regex<PosixBasicParser>::run_optimization_passes();
|
|
template void Regex<PosixExtendedParser>::run_optimization_passes();
|
|
template void Regex<ECMA262Parser>::run_optimization_passes();
|
|
}
|