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Merge pull request #43775 from vnen/gdscript-fix-stack

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GDScript: Fix mishandling of stack pointers
This commit is contained in:
Rémi Verschelde 2020-11-25 16:25:51 +01:00 committed by GitHub
commit a5ee8d881f
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GPG Key ID: 4AEE18F83AFDEB23
4 changed files with 104 additions and 35 deletions
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69
modules/gdscript/gdscript_byte_codegen.cpp
View File

@ -77,11 +77,22 @@ uint32_t GDScriptByteCodeGenerator::add_or_get_name(const StringName &p_name) {
uint32_t GDScriptByteCodeGenerator::add_temporary() {
current_temporaries++;
return increase_stack();
int idx = increase_stack();
#ifdef DEBUG_ENABLED
temp_stack.push_back(idx);
#endif
return idx;
}
void GDScriptByteCodeGenerator::pop_temporary() {
ERR_FAIL_COND(current_temporaries == 0);
current_stack_size--;
#ifdef DEBUG_ENABLED
if (temp_stack.back()->get() != current_stack_size) {
ERR_PRINT("Mismatched popping of temporary value");
}
temp_stack.pop_back();
#endif
current_temporaries--;
}
@ -111,6 +122,11 @@ void GDScriptByteCodeGenerator::write_start(GDScript *p_script, const StringName
}
GDScriptFunction *GDScriptByteCodeGenerator::write_end() {
#ifdef DEBUG_ENABLED
if (current_temporaries != 0) {
ERR_PRINT("Non-zero temporary variables at end of function: " + itos(current_temporaries));
}
#endif
append(GDScriptFunction::OPCODE_END, 0);
if (constant_map.size()) {
@ -905,23 +921,39 @@ void GDScriptByteCodeGenerator::write_endif() {
if_jmp_addrs.pop_back();
}
void GDScriptByteCodeGenerator::write_for(const Address &p_variable, const Address &p_list) {
int counter_pos = add_temporary() | (GDScriptFunction::ADDR_TYPE_STACK << GDScriptFunction::ADDR_BITS);
int container_pos = add_temporary() | (GDScriptFunction::ADDR_TYPE_STACK << GDScriptFunction::ADDR_BITS);
void GDScriptByteCodeGenerator::start_for(const GDScriptDataType &p_iterator_type, const GDScriptDataType &p_list_type) {
Address counter(Address::LOCAL_VARIABLE, add_local("@counter_pos", p_iterator_type), p_iterator_type);
Address container(Address::LOCAL_VARIABLE, add_local("@container_pos", p_list_type), p_list_type);
current_breaks_to_patch.push_back(List<int>());
// Store state.
for_counter_variables.push_back(counter);
for_container_variables.push_back(container);
}
void GDScriptByteCodeGenerator::write_for_assignment(const Address &p_variable, const Address &p_list) {
const Address &container = for_container_variables.back()->get();
// Assign container.
append(GDScriptFunction::OPCODE_ASSIGN, 2);
append(container_pos);
append(container);
append(p_list);
for_iterator_variables.push_back(p_variable);
}
void GDScriptByteCodeGenerator::write_for() {
const Address &iterator = for_iterator_variables.back()->get();
const Address &counter = for_counter_variables.back()->get();
const Address &container = for_container_variables.back()->get();
current_breaks_to_patch.push_back(List<int>());
GDScriptFunction::Opcode begin_opcode = GDScriptFunction::OPCODE_ITERATE_BEGIN;
GDScriptFunction::Opcode iterate_opcode = GDScriptFunction::OPCODE_ITERATE;
if (p_list.type.has_type) {
if (p_list.type.kind == GDScriptDataType::BUILTIN) {
switch (p_list.type.builtin_type) {
if (container.type.has_type) {
if (container.type.kind == GDScriptDataType::BUILTIN) {
switch (container.type.builtin_type) {
case Variant::INT:
begin_opcode = GDScriptFunction::OPCODE_ITERATE_BEGIN_INT;
iterate_opcode = GDScriptFunction::OPCODE_ITERATE_INT;
@ -1005,9 +1037,9 @@ void GDScriptByteCodeGenerator::write_for(const Address &p_variable, const Addre
// Begin loop.
append(begin_opcode, 3);
append(counter_pos);
append(container_pos);
append(p_variable);
append(counter);
append(container);
append(iterator);
for_jmp_addrs.push_back(opcodes.size());
append(0); // End of loop address, will be patched.
append(GDScriptFunction::OPCODE_JUMP, 0);
@ -1017,9 +1049,9 @@ void GDScriptByteCodeGenerator::write_for(const Address &p_variable, const Addre
int continue_addr = opcodes.size();
continue_addrs.push_back(continue_addr);
append(iterate_opcode, 3);
append(counter_pos);
append(container_pos);
append(p_variable);
append(counter);
append(container);
append(iterator);
for_jmp_addrs.push_back(opcodes.size());
append(0); // Jump destination, will be patched.
}
@ -1042,9 +1074,10 @@ void GDScriptByteCodeGenerator::write_endfor() {
}
current_breaks_to_patch.pop_back();
// Remove loop temporaries.
pop_temporary();
pop_temporary();
// Pop state.
for_iterator_variables.pop_back();
for_counter_variables.pop_back();
for_container_variables.pop_back();
}
void GDScriptByteCodeGenerator::start_while_condition() {

30
modules/gdscript/gdscript_byte_codegen.h
View File

@ -43,6 +43,7 @@ class GDScriptByteCodeGenerator : public GDScriptCodeGenerator {
Vector<int> opcodes;
List<Map<StringName, int>> stack_id_stack;
Map<StringName, int> stack_identifiers;
List<int> stack_identifiers_counts;
Map<StringName, int> local_constants;
List<GDScriptFunction::StackDebug> stack_debug;
@ -51,11 +52,16 @@ class GDScriptByteCodeGenerator : public GDScriptCodeGenerator {
int current_stack_size = 0;
int current_temporaries = 0;
int current_locals = 0;
int current_line = 0;
int stack_max = 0;
int instr_args_max = 0;
int ptrcall_max = 0;
#ifdef DEBUG_ENABLED
List<int> temp_stack;
#endif
HashMap<Variant, int, VariantHasher, VariantComparator> constant_map;
Map<StringName, int> name_map;
#ifdef TOOLS_ENABLED
@ -72,8 +78,12 @@ class GDScriptByteCodeGenerator : public GDScriptCodeGenerator {
Map<Variant::ValidatedConstructor, int> constructors_map;
Map<MethodBind *, int> method_bind_map;
List<int> if_jmp_addrs; // List since this can be nested.
// Lists since these can be nested.
List<int> if_jmp_addrs;
List<int> for_jmp_addrs;
List<Address> for_iterator_variables;
List<Address> for_counter_variables;
List<Address> for_container_variables;
List<int> while_jmp_addrs;
List<int> continue_addrs;
@ -89,6 +99,7 @@ class GDScriptByteCodeGenerator : public GDScriptCodeGenerator {
List<List<int>> match_continues_to_patch;
void add_stack_identifier(const StringName &p_id, int p_stackpos) {
current_locals++;
stack_identifiers[p_id] = p_stackpos;
if (debug_stack) {
block_identifiers[p_id] = p_stackpos;
@ -102,17 +113,26 @@ class GDScriptByteCodeGenerator : public GDScriptCodeGenerator {
}
void push_stack_identifiers() {
stack_identifiers_counts.push_back(current_locals);
stack_id_stack.push_back(stack_identifiers);
if (debug_stack) {
block_identifier_stack.push_back(block_identifiers);
Map<StringName, int> block_ids(block_identifiers);
block_identifier_stack.push_back(block_ids);
block_identifiers.clear();
}
}
void pop_stack_identifiers() {
current_locals = stack_identifiers_counts.back()->get();
stack_identifiers_counts.pop_back();
stack_identifiers = stack_id_stack.back()->get();
current_stack_size = stack_identifiers.size() + current_temporaries;
stack_id_stack.pop_back();
#ifdef DEBUG_ENABLED
if (current_temporaries != 0) {
ERR_PRINT("Leaving block with non-zero temporary variables: " + itos(current_temporaries));
}
#endif
current_stack_size = current_locals;
if (debug_stack) {
for (Map<StringName, int>::Element *E = block_identifiers.front(); E; E = E->next()) {
@ -397,7 +417,9 @@ public:
virtual void write_if(const Address &p_condition) override;
virtual void write_else() override;
virtual void write_endif() override;
virtual void write_for(const Address &p_variable, const Address &p_list) override;
virtual void start_for(const GDScriptDataType &p_iterator_type, const GDScriptDataType &p_list_type) override;
virtual void write_for_assignment(const Address &p_variable, const Address &p_list) override;
virtual void write_for() override;
virtual void write_endfor() override;
virtual void start_while_condition() override;
virtual void write_while(const Address &p_condition) override;

4
modules/gdscript/gdscript_codegen.h
View File

@ -139,7 +139,9 @@ public:
// virtual void write_elseif(const Address &p_condition) = 0; This kind of makes things more difficult for no real benefit.
virtual void write_else() = 0;
virtual void write_endif() = 0;
virtual void write_for(const Address &p_variable, const Address &p_list) = 0;
virtual void start_for(const GDScriptDataType &p_iterator_type, const GDScriptDataType &p_list_type) = 0;
virtual void write_for_assignment(const Address &p_variable, const Address &p_list) = 0;
virtual void write_for() = 0;
virtual void write_endfor() = 0;
virtual void start_while_condition() = 0; // Used to allow a jump to the expression evaluation.
virtual void write_while(const Address &p_condition) = 0;

36
modules/gdscript/gdscript_compiler.cpp
View File

@ -1474,13 +1474,27 @@ Error GDScriptCompiler::_parse_block(CodeGen &codegen, const GDScriptParser::Sui
codegen.start_block();
// Evaluate the match expression.
GDScriptCodeGenerator::Address value_local = codegen.add_local("@match_value", _gdtype_from_datatype(match->test->get_datatype()));
GDScriptCodeGenerator::Address value = _parse_expression(codegen, error, match->test);
if (error) {
return error;
}
// Assign to local.
// TODO: This can be improved by passing the target to parse_expression().
gen->write_assign(value_local, value);
if (value.mode == GDScriptCodeGenerator::Address::TEMPORARY) {
codegen.generator->pop_temporary();
}
// Then, let's save the type of the value in the stack too, so we can reuse for later comparisons.
GDScriptCodeGenerator::Address type = codegen.add_temporary();
GDScriptDataType typeof_type;
typeof_type.has_type = true;
typeof_type.kind = GDScriptDataType::BUILTIN;
typeof_type.builtin_type = Variant::INT;
GDScriptCodeGenerator::Address type = codegen.add_local("@match_type", typeof_type);
Vector<GDScriptCodeGenerator::Address> typeof_args;
typeof_args.push_back(value);
gen->write_call_builtin(type, GDScriptFunctions::TYPE_OF, typeof_args);
@ -1534,12 +1548,6 @@ Error GDScriptCompiler::_parse_block(CodeGen &codegen, const GDScriptParser::Sui
gen->write_endif();
}
gen->pop_temporary();
if (value.mode == GDScriptCodeGenerator::Address::TEMPORARY) {
codegen.generator->pop_temporary();
}
gen->end_match();
} break;
case GDScriptParser::Node::IF: {
@ -1577,12 +1585,20 @@ Error GDScriptCompiler::_parse_block(CodeGen &codegen, const GDScriptParser::Sui
codegen.start_block();
GDScriptCodeGenerator::Address iterator = codegen.add_local(for_n->variable->name, _gdtype_from_datatype(for_n->variable->get_datatype()));
gen->start_for(iterator.type, _gdtype_from_datatype(for_n->list->get_datatype()));
GDScriptCodeGenerator::Address list = _parse_expression(codegen, error, for_n->list);
if (error) {
return error;
}
gen->write_for(iterator, list);
gen->write_for_assignment(iterator, list);
if (list.mode == GDScriptCodeGenerator::Address::TEMPORARY) {
codegen.generator->pop_temporary();
}
gen->write_for();
error = _parse_block(codegen, for_n->loop);
if (error) {
@ -1591,10 +1607,6 @@ Error GDScriptCompiler::_parse_block(CodeGen &codegen, const GDScriptParser::Sui
gen->write_endfor();
if (list.mode == GDScriptCodeGenerator::Address::TEMPORARY) {
codegen.generator->pop_temporary();
}
codegen.end_block();
} break;
case GDScriptParser::Node::WHILE: {