+ Reference node's children

[sudmit0802]

According to Issue #1356 a child for reference node obviously exists on AST graph, but it doesn't exists in vector with children, so it looks like incorrect work of API for interacting with ASTs.

There were two ways to solve this:
1.) I always have to cast SharedAbstractNode to ReferenceNode then getSymbolicExpresssion from it and then getAst from it again to finally get a real node with children. (jungles)
2.) Use AstContext::unroll(ast_node) to get a real node with children. (cannon)

In this PR I add a real node with its children as a child of Reference node in Constructor. The lifetime of a real node will not change from this, and the API will become consistent and convenient without unnecessary static_cast.

[JonathanSalwan]

thx. let me few days to really check if doesn't break anything :)

[sudmit0802]

Did it break everything? :)

[JonathanSalwan]

CIs are ok but they do not really fully test the library :). To be honest, it's quite surprising, and it's a good news, that it did not break the CI :).

However, I have to double check all these following lines (the list is probably not exhaustive). My feeling is that for all references to REFERENCE_NODE, the code is now useless? and for all references to getChildren(), I have to check if it's okay to go through children of a ReferenceNode.

Triton/src/libtriton/ast/ast.cpp

Line 3573 in ae652c8

return triton::ast::shallowCopy(reinterpret_cast<ReferenceNode*>(node)->getSymbolicExpression()->getAst().get(), unroll);

Triton/src/libtriton/ast/ast.cpp

Lines 3683 to 3688 in ae652c8

	if (unroll && ast->getType() == REFERENCE_NODE) {
	const SharedAbstractNode& ref = reinterpret_cast<ReferenceNode*>(ast.get())->getSymbolicExpression()->getAst();
	if (visited.find(ref.get()) == visited.end()) {
	worklist.push({ref, false});
	}
	}

Triton/src/libtriton/ast/ast.cpp

Lines 3729 to 3731 in ae652c8

	if (current->getType() == REFERENCE_NODE) {
	worklist.push(reinterpret_cast<triton::ast::ReferenceNode*>(current)->getSymbolicExpression()->getAst().get());
	}

Triton/src/libtriton/ast/ast.cpp

Line 3743 in ae652c8

SharedAbstractNode dereference(const SharedAbstractNode& node) {

Triton/src/libtriton/engines/symbolic/symbolicEngine.cpp

Lines 498 to 502 in ae652c8

	if (n->getType() == triton::ast::REFERENCE_NODE) {
	auto expr = reinterpret_cast<triton::ast::ReferenceNode*>(n.get())->getSymbolicExpression();
	auto eid = expr->getId();
	exprs[eid] = expr;
	}

Triton/src/libtriton/engines/symbolic/symbolicSimplification.cpp

Lines 267 to 282 in ae652c8

	for (const auto& x : access) {
	auto refs = triton::ast::search(x.second, triton::ast::REFERENCE_NODE);
	for (const auto& ref : refs) {
	auto expr = reinterpret_cast<triton::ast::ReferenceNode*>(ref.get())->getSymbolicExpression();
	auto eid = expr->getId();
	lifetime[eid] = expr;
	}
	if (x.first.getLeaAst()) {
	auto refs = triton::ast::search(x.first.getLeaAst(), triton::ast::REFERENCE_NODE);
	for (const auto& ref : refs) {
	auto expr = reinterpret_cast<triton::ast::ReferenceNode*>(ref.get())->getSymbolicExpression();
	auto eid = expr->getId();
	lifetime[eid] = expr;
	}
	}
	}

Triton/src/libtriton/engines/synthesis/synthesizer.cpp

Lines 350 to 352 in ae652c8

	if (current->getType() == triton::ast::REFERENCE_NODE) {
	worklist.push(reinterpret_cast<triton::ast::ReferenceNode*>(current)->getSymbolicExpression()->getAst().get());
	}

Triton/src/libtriton/engines/synthesis/synthesizer.cpp

Lines 422 to 424 in ae652c8

	if (current->getType() == triton::ast::REFERENCE_NODE) {
	worklist.push(reinterpret_cast<triton::ast::ReferenceNode*>(current)->getSymbolicExpression()->getAst().get());
	}

Triton/src/libtriton/engines/symbolic/symbolicSimplification.cpp

Line 201 in ae652c8

for (triton::uint32 index = 0; index < ast->getChildren().size(); index++) {

Triton/src/libtriton/engines/lifters/liftingToDot.cpp

Line 407 in ae652c8

for (auto const& child : node->getChildren()) {

Triton/src/libtriton/engines/lifters/liftingToSMT.cpp

Line 182 in ae652c8

for (const auto& child : n->getChildren()) {

Triton/src/libtriton/ast/llvm/tritonToLLVM.cpp

Line 121 in ae652c8

for (auto&& n : node->getChildren()) {

Triton/src/libtriton/ast/bitwuzla/tritonToBitwuzla.cpp

Line 60 in ae652c8

for (auto&& n : node->getChildren()) {

Triton/src/libtriton/ast/z3/tritonToZ3.cpp

Line 59 in ae652c8

for (auto&& n : node->getChildren()) {

Triton/src/libtriton/ast/ast.cpp

Lines 3604 to 3623 in ae652c8

	SharedAbstractNode newInstance(AbstractNode* node, bool unroll) {
	std::unordered_map<AbstractNode*, SharedAbstractNode> exprs;
	auto nodes = childrenExtraction(node->shared_from_this(), unroll, true);
	for (auto&& n : nodes) {
	/* Do a copy of all children */
	const auto& newNode = shallowCopy(n.get(), unroll);
	exprs[n.get()] = newNode;
	/* For each child, set its parent */
	auto& children = newNode->getChildren();
	for (auto& child : children) {
	child = exprs[child.get()];
	child->setParent(newNode.get());
	}
	}
	/* Return the root node */
	return exprs.at(node);
	}