class LLVMGen:
builder: Optional[IRBuilder]
current_func: Optional[RIALFunction]
conditional_block: Optional[LLVMBlock]
end_block: Optional[LLVMBlock]
current_block: Optional[LLVMBlock]
current_struct: Optional[RIALIdentifiedStructType]
currently_unsafe: bool
def __init__(self):
self.current_block = None
self.conditional_block = None
self.end_block = None
self.current_func = None
self.builder = None
self.current_struct = None
self.currently_unsafe = False
def _get_by_identifier(self, identifier: str, variable: Optional = None) -> Optional:
if isinstance(variable, RIALVariable):
variable = variable.backing_value
if not variable is None and hasattr(variable, 'type') and isinstance(variable.type, PointerType):
if isinstance(variable.type.pointee, RIALIdentifiedStructType):
struct = ParserState.find_struct(variable.type.pointee.name)
if struct is None:
return None
if not self.check_struct_access_allowed(struct):
raise PermissionError(f"Tried accesssing struct {struct.name}")
prop = struct.definition.properties[identifier]
if prop is None:
return None
# Check property access
if not self.check_property_access_allowed(struct, prop[1]):
raise PermissionError(f"Tried to access property {prop[1].name} but it was not allowed!")
variable = self.builder.gep(variable, [ir.Constant(ir.IntType(32), 0),
ir.Constant(ir.IntType(32), prop[0])])
else:
# Search local variables
variable = self.current_block.get_named_value(identifier)
# Search for a global variable
if variable is None:
glob = ParserState.find_global(identifier)
# Check if in same module
if glob is not None:
if glob.backing_value.parent.name != ParserState.module().name:
glob_current_module = ParserState.module().get_global_safe(glob.name)
if glob_current_module is not None:
variable = glob_current_module
else:
# TODO: Check if global access is allowed
variable = self.gen_global(glob.name, None, glob.backing_value.type.pointee,
glob.access_modifier, "external",
glob.backing_value.global_constant)
else:
variable = glob.backing_value
# If variable is none, just do a full function search
if variable is None:
variable = ParserState.find_function(identifier)
if variable is None:
variable = ParserState.find_function(mangle_function_name(identifier, []))
# Check if in same module
if variable is not None:
if variable.module.name != ParserState.module().name:
variable_current_module = ParserState.module().get_global_safe(variable.name)
if variable_current_module is not None:
variable = variable_current_module
else:
variable = self.create_function_with_type(variable.name, variable.name, variable.function_type,
variable.linkage,
variable.calling_convention,
variable.definition)
return variable
def get_exact_definition(self, identifier: str):
identifiers = identifier.split('.')
variable = None
for ident in identifiers:
variable = self._get_by_identifier(ident, variable)
# Search for the full name
if variable is None:
variable = self._get_by_identifier(identifier, variable)
if variable is None:
return None
if isinstance(variable, RIALFunction):
return variable
if isinstance(variable, RIALVariable):
return variable
return RIALVariable(identifier, map_llvm_to_type(variable.type.pointee), variable)
def get_definition(self, identifier: str):
variable = self.get_exact_definition(identifier)
# Search with module specifier
if variable is None:
if ':' in identifier:
parts = identifier.split(':')
module_name = ':'.join(parts[0:-1])
if CompilationManager.check_module_already_compiled(module_name):
return None
if ParserState.add_dependency_and_wait(module_name):
return self.get_definition(identifier)
return None
return variable
def gen_integer(self, number: int, length: int, unsigned: bool = False):
return ir.Constant((unsigned and LLVMUIntType(length) or ir.IntType(length)), number)
def gen_half(self, number: float):
return ir.Constant(ir.HalfType(), number)
def gen_float(self, number: float):
return ir.Constant(ir.FloatType(), number)
def gen_double(self, number: float):
return ir.Constant(ir.DoubleType(), number)
def gen_global(self, name: str, value: Optional[ir.Constant], ty: Type, access_modifier: RIALAccessModifier,
linkage: str,
constant: bool):
rial_variable = ParserState.module().get_rial_variable(name)
if rial_variable is not None:
return rial_variable.backing_value
glob = ir.GlobalVariable(ParserState.module(), ty, name=name)
glob.linkage = linkage
glob.global_constant = constant
if value is not None:
glob.initializer = value
rial_variable = RIALVariable(name, map_llvm_to_type(ty), glob,
access_modifier)
ParserState.module().global_variables.append(rial_variable)
return glob
def gen_string_lit(self, name: str, value: str):
value = eval("'{}'".format(value))
# TODO: Remove the always-added \0 once we don't need that anymore
arr = bytearray(value.encode("utf-8") + b"\x00")
const_char_arr = ir.Constant(ir.ArrayType(ir.IntType(8), len(arr)), arr)
glob = self.gen_global(name, const_char_arr, const_char_arr.type, RIALAccessModifier.PRIVATE, "private", True)
return glob
def gen_load_if_necessary(self, value):
if isinstance(value, AllocaInstr) or isinstance(value, Argument) or isinstance(value, FormattedConstant) or (
hasattr(value, 'type') and isinstance(value.type, PointerType)):
return self.builder.load(value)
return value
def gen_var_if_necessary(self, value):
# Check if variable is not:
# - Pointer
# - Alloca (Variable), inherently pointer
# - Argument (always pointer)
# - Type is pointer (e.g. getelementptr instruction)
if not (isinstance(value, PointerType) or isinstance(value, AllocaInstr) or isinstance(value, Argument)
or isinstance(value.type, PointerType)):
allocad = self.builder.alloca(value.type)
self.builder.store(value, allocad)
return allocad
return value
def gen_addition(self, left, right):
left = self.gen_load_if_necessary(left)
right = self.gen_load_if_necessary(right)
if isinstance(left.type, ir.IntType):
return self.builder.add(left, right)
if isinstance(left.type, ir.FloatType) or isinstance(left.type, ir.DoubleType):
return self.builder.fadd(left, right)
return None
def gen_subtraction(self, left, right):
left = self.gen_load_if_necessary(left)
right = self.gen_load_if_necessary(right)
if isinstance(left.type, ir.IntType):
return self.builder.sub(left, right)
if isinstance(left.type, ir.FloatType) or isinstance(left.type, ir.DoubleType):
return self.builder.fsub(left, right)
return None
def gen_multiplication(self, left, right):
left = self.gen_load_if_necessary(left)
right = self.gen_load_if_necessary(right)
if isinstance(left.type, ir.IntType):
return self.builder.mul(left, right)
if isinstance(left.type, ir.FloatType) or isinstance(left.type, ir.DoubleType):
return self.builder.fmul(left, right)
return None
def gen_division(self, left, right):
left = self.gen_load_if_necessary(left)
right = self.gen_load_if_necessary(right)
if isinstance(left.type, LLVMUIntType):
return self.builder.udiv(left, right)
if isinstance(left.type, ir.IntType):
return self.builder.sdiv(left, right)
if isinstance(left.type, ir.FloatType) or isinstance(left.type, ir.DoubleType):
return self.builder.fdiv(left, right)
return None
def gen_comparison(self, comparison: str, left, right):
left = left
right = right
if isinstance(left.type, LLVMUIntType) or isinstance(left.type, ir.PointerType):
return self.builder.icmp_unsigned(comparison, left, right)
if isinstance(left.type, ir.IntType):
return self.builder.icmp_signed(comparison, left, right)
if isinstance(left.type, ir.FloatType) or isinstance(left.type, ir.DoubleType):
return self.builder.fcmp_ordered(comparison, left, right)
return None
def gen_shorthand(self, variable, value, operation):
loaded = self.builder.load(variable)
value = self.gen_load_if_necessary(value)
mathed = None
if operation == "+":
mathed = self.gen_addition(loaded, value)
elif operation == "-":
mathed = self.gen_subtraction(loaded, value)
elif operation == "*":
mathed = self.gen_multiplication(loaded, value)
elif operation == "/":
mathed = self.gen_division(loaded, value)
self.builder.store(mathed, variable)
return mathed
def gen_function_call(self, possible_function_names: List[str],
llvm_args: List) -> Optional[CallInstr]:
func = None
# Check if it's actually a local variable
for function_name in possible_function_names:
var = self.get_definition(function_name)
if var is not None:
func = var
# Try to find by function name
if func is None:
for function_name in possible_function_names:
func = ParserState.find_function(function_name)
if func is not None:
break
# Try to find by function name but enable canonical name
if func is None:
rial_arg_types = [map_llvm_to_type(arg.type) for arg in llvm_args]
for function_name in possible_function_names:
func = ParserState.find_function(function_name, rial_arg_types)
if func is not None:
break
if func is None:
return None
if isinstance(func, RIALVariable):
func = func.backing_value
if isinstance(func, ir.PointerType) and isinstance(func.pointee, RIALFunction):
func = func.pointee
elif isinstance(func, GlobalVariable) or isinstance(func, AllocaInstr):
loaded_func = self.builder.load(func)
call = self.builder.call(loaded_func, llvm_args)
return call
# Check if call is allowed
if not self.check_function_call_allowed(func):
raise PermissionError(f"Tried calling function {func.name} from {self.current_func.name}")
# Check if function is declared in current module
if ParserState.module().get_global_safe(func.name) is None:
func = self.create_function_with_type(func.name, func.canonical_name, func.function_type, func.linkage,
func.calling_convention, func.definition)
args = list()
# Gen a load if necessary
for i, arg in enumerate(llvm_args):
llvm_arg = func.definition.rial_args[i].llvm_type
if llvm_arg == arg.type:
args.append(arg)
continue
args.append(self.builder.load(arg))
# Check type matching
for i, arg in enumerate(args):
if len(func.args) > i and arg.type != func.args[i].type:
# Check for base types
ty = isinstance(arg.type, PointerType) and arg.type.pointee or arg.type
func_arg_type = isinstance(func.args[i].type, PointerType) and func.args[i].type.pointee or func.args[
i].type
if isinstance(ty, RIALIdentifiedStructType):
struct = ParserState.find_struct(ty.name)
if struct is not None:
found = False
# Check if a base struct matches the type expected
# TODO: Recursive check
for base_struct in struct.definition.base_structs:
if base_struct == func_arg_type.name:
args.remove(arg)
args.insert(i, self.builder.bitcast(arg, ir.PointerType(base_struct)))
found = True
break
if found:
continue
# TODO: SLOC information
raise TypeError(
f"Function {func.name} expects a {func.args[i].type} but got a {arg.type}")
# Gen call
return self.builder.call(func, args)
def gen_no_op(self):
self.gen_function_call(["rial:builtin:settings:nop_function"], [])
def check_function_call_allowed(self, func: RIALFunction):
# Unsafe in safe context is big no-no
if func.definition.unsafe and not self.currently_unsafe:
return False
# Public is always okay
if func.definition.access_modifier == RIALAccessModifier.PUBLIC:
return True
# Internal only when it's the same TLM
if func.definition.access_modifier == RIALAccessModifier.INTERNAL:
return func.module.name.split(':')[0] == ParserState.module().name.split(':')[0]
# Private is harder
if func.definition.access_modifier == RIALAccessModifier.PRIVATE:
# Allowed if not in struct and in current module
if func.definition.struct == "" and func.module.name == ParserState.module().name:
return True
# Allowed if in same struct irregardless of module
if self.current_struct is not None and self.current_struct.name == func.definition.struct:
return True
return False
def check_property_access_allowed(self, struct: RIALIdentifiedStructType, prop: RIALVariable):
# Same struct, anything goes
if self.current_struct is not None and self.current_struct.name == struct.name:
return True
# Unless it's private it's okay
if prop.access_modifier == RIALAccessModifier.PRIVATE:
return False
return True
def check_struct_access_allowed(self, struct: RIALIdentifiedStructType):
# Public is always okay
if struct.definition.access_modifier == RIALAccessModifier.PUBLIC:
return True
# Private and same module
if struct.definition.access_modifier == RIALAccessModifier.PRIVATE:
return struct.module_name == ParserState.module().name
# Internal and same TLM
if struct.definition.access_modifier == RIALAccessModifier.INTERNAL:
return struct.module_name.split(':')[0] == ParserState.module().name.split(':')[0]
return False
def declare_nameless_variable_from_rial_type(self, rial_type: str, value):
returned_type = ParserState.map_type_to_llvm_no_pointer(rial_type)
if isinstance(returned_type, ir.VoidType):
return value
returned_value = self.builder.alloca(returned_type)
if isinstance(ParserState.map_type_to_llvm(rial_type), PointerType):
self.builder.store(self.builder.load(value), returned_value)
else:
self.builder.store(value, returned_value)
return returned_value
def assign_non_constant_global_variable(self, glob: GlobalVariable, value):
if self.current_func.name != "global_ctor":
raise PermissionError()
if isinstance(value, AllocaInstr):
value = self.builder.load(value)
elif isinstance(value, PointerType):
value = self.builder.load(value.pointee)
elif isinstance(value, FormattedConstant):
value = self.builder.load(value)
self.builder.store(value, glob)
def declare_non_constant_global_variable(self, identifier: str, value, access_modifier: RIALAccessModifier,
linkage: str):
"""
Needs to be called with create_in_global_ctor or otherwise the store/load operations are going to fail.
:param identifier:
:param value:
:param access_modifier:
:param linkage:
:return:
"""
if ParserState.module().get_global_safe(identifier) is not None:
return None
if self.current_func.name != "global_ctor":
return None
if isinstance(value, AllocaInstr):
variable = self.gen_global(identifier, null(value.type.pointee), value.type.pointee, access_modifier,
linkage, False)
elif isinstance(value, PointerType):
variable = self.gen_global(identifier, null(value.pointee.type), value.pointee.type, access_modifier,
linkage, False)
elif isinstance(value, FormattedConstant) or isinstance(value, AllocaInstr):
variable = self.gen_global(identifier, null(value.type.pointee), value.type.pointee, access_modifier,
linkage, False)
elif isinstance(value, Constant):
variable = self.gen_global(identifier, null(value.type), value.type, access_modifier, linkage, False)
else:
variable = self.gen_global(identifier, null(value.type), value.type, access_modifier, linkage, False)
self.assign_non_constant_global_variable(variable, value)
return variable
def declare_variable(self, identifier: str, value) -> Optional[AllocaInstr]:
variable = self.current_block.get_named_value(identifier)
if variable is not None:
return None
if isinstance(value, AllocaInstr) or isinstance(value, PointerType):
variable = value
variable.name = identifier
elif isinstance(value, CastInstr) and value.opname == "inttoptr":
variable = self.builder.alloca(value.type.pointee)
variable.name = identifier
rial_type = f"{map_llvm_to_type(value.type)}"
variable.set_metadata('type',
ParserState.module().add_metadata((rial_type,)))
self.builder.store(self.builder.load(value), variable)
elif isinstance(value, FormattedConstant):
variable = self.builder.alloca(value.type.pointee)
variable.name = identifier
rial_type = f"{map_llvm_to_type(value.type)}"
variable.set_metadata('type',
ParserState.module().add_metadata((rial_type,)))
self.builder.store(self.builder.load(value), variable)
elif isinstance(value, Constant):
variable = self.builder.alloca(value.type)
variable.name = identifier
rial_type = f"{map_llvm_to_type(value.type)}"
variable.set_metadata('type',
ParserState.module().add_metadata((rial_type,)))
self.builder.store(value, variable)
else:
variable = self.builder.alloca(value.type)
variable.name = identifier
rial_type = f"{map_llvm_to_type(value.type)}"
variable.set_metadata('type', ParserState.module().add_metadata((rial_type,)))
self.builder.store(value, variable)
self.current_block.add_named_value(identifier, variable)
return variable
def assign_to_variable(self, identifier: Union[str, Any], value):
if isinstance(identifier, str):
variable = self.get_definition(identifier)
else:
variable = identifier
if variable is None:
return None
if isinstance(value, AllocaInstr):
value = self.builder.load(value)
elif isinstance(value, PointerType) and not isinstance(variable, PointerType):
value = self.builder.load(value.pointee)
self.builder.store(value, variable)
return variable
def create_block(self, block_name: str, parent: Optional[LLVMBlock] = None,
sibling: Optional[LLVMBlock] = None) -> \
Optional[LLVMBlock]:
if parent is None and sibling is None and block_name != "entry" and len(self.current_func.basic_blocks) > 0:
return None
block = self.builder.append_basic_block(block_name)
llvmblock = create_llvm_block(block, parent, sibling)
return llvmblock
def create_loop(self, base_block_name: str, parent: LLVMBlock):
(conditional_llvm_block, body_llvm_block, end_llvm_block) = self.create_conditional_block(base_block_name,
parent)
self.conditional_block = conditional_llvm_block
self.end_block = end_llvm_block
return conditional_llvm_block, body_llvm_block, end_llvm_block,
def create_switch_blocks(self, base_block_name: str, parent: LLVMBlock, count_of_cases: int,
default_case: bool) -> \
List[LLVMBlock]:
blocks = list()
for i in range(0, count_of_cases):
blocks.append(self.create_block(f"{base_block_name}.case.{i}", parent, None))
if default_case:
blocks.append(self.create_block(f"{base_block_name}.default", parent))
return blocks
def create_conditional_block(self, base_block_name: str, parent: LLVMBlock) -> Tuple[
LLVMBlock, LLVMBlock, LLVMBlock]:
# Create three blocks, one condition, one body, and one after the loop
conditional_llvm_block = self.create_block(f"{base_block_name}.condition", parent, None)
body_llvm_block = self.create_block(f"{base_block_name}.body", conditional_llvm_block, None)
end_llvm_block = self.create_block(f"{base_block_name}.end", None, parent)
return conditional_llvm_block, body_llvm_block, end_llvm_block,
def create_conditional_block_with_else(self, base_block_name: str, parent: LLVMBlock):
(conditional_block, body_block, else_block) = self.create_conditional_block(base_block_name, parent)
# Transform end block into else block
else_block.block.name = f"{base_block_name}.else"
else_block.sibling = None
else_block.parent = conditional_block
# Create new end block
end_block = self.create_block(f"{base_block_name}.if_else.end", None, conditional_block.parent)
return conditional_block, body_block, else_block, end_block
def create_jump_if_not_exists(self, target_block: LLVMBlock) -> Optional[Branch]:
if self.current_block.block.terminator is None:
return self.builder.branch(target_block.block)
return None
def create_conditional_jump(self, condition, true_block: LLVMBlock, false_block: LLVMBlock,
true_branch_weight: int = 50, false_branch_weight: int = 50) -> ConditionalBranch:
# Check if condition is a variable, we need to load that for LLVM
condition = self.gen_load_if_necessary(condition)
cbranch = self.builder.cbranch(condition, true_block.block, false_block.block)
cbranch.set_weights([true_branch_weight, false_branch_weight])
return cbranch
def create_jump(self, target_block: LLVMBlock):
return self.builder.branch(target_block.block)
def enter_block(self, llvmblock: LLVMBlock):
self.current_block = llvmblock
self.builder.position_at_start(self.current_block.block)
def enter_block_end(self, llvmblock: LLVMBlock):
self.current_block = llvmblock
self.builder.position_at_end(self.current_block.block)
def create_identified_struct(self, name: str, linkage: str,
rial_access_modifier: RIALAccessModifier,
base_llvm_structs: List[RIALIdentifiedStructType],
body: List[RIALVariable]) -> RIALIdentifiedStructType:
# Build normal struct and switch out with RIALStruct
struct = ParserState.module().context.get_identified_type(name)
rial_struct = RIALIdentifiedStructType(struct.context, struct.name, struct.packed)
ParserState.module().context.identified_types[struct.name] = rial_struct
struct = rial_struct
ParserState.module().structs.append(struct)
# Create metadata definition
struct_def = StructDefinition(rial_access_modifier)
# Build body and body definition
props_def = dict()
props = list()
prop_offset = 0
for deriv in base_llvm_structs:
for prop in deriv.definition.properties.values():
props.append(ParserState.map_type_to_llvm(prop[1].rial_type))
props_def[prop[1].name] = (prop_offset, prop[1])
prop_offset += 1
struct_def.base_structs.append(deriv.name)
for bod in body:
props.append(ParserState.map_type_to_llvm(bod.rial_type))
props_def[bod.name] = (prop_offset, bod)
prop_offset += 1
struct.set_body(*tuple(props))
struct.module_name = ParserState.module().name
self.current_struct = struct
struct_def.properties = props_def
# Store def in metadata
struct.definition = struct_def
return struct
def finish_struct(self):
self.current_struct = None
self.current_func = None
self.current_block = None
def create_function_with_type(self, name: str, canonical_name: str, ty: FunctionType,
linkage: str,
calling_convention: str,
function_def: FunctionDefinition) -> RIALFunction:
"""
Creates an IR Function with the specified arguments. NOTHING MORE.
:param canonical_name:
:param canonical_name:
:param function_def:
:param name:
:param ty:
:param linkage:
:param calling_convention:
:return:
"""
# Create function with specified linkage (internal -> module only)
func = RIALFunction(ParserState.module(), ty, name=name, canonical_name=canonical_name)
func.linkage = linkage
func.calling_convention = calling_convention
func.definition = function_def
# Set argument names
for i, arg in enumerate(func.args):
arg.name = function_def.rial_args[i].name
ParserState.module().rial_functions.append(func)
return func
def create_function_body(self, func: RIALFunction, rial_arg_types: List[str]):
self.current_func = func
# Create entry block
bb = func.append_basic_block("entry")
llvm_bb = create_llvm_block(bb)
self.current_block = llvm_bb
if self.builder is None:
self.builder = IRBuilder(bb)
self.builder.position_at_start(bb)
# Allocate new variables for the passed arguments
for i, arg in enumerate(func.args):
# Don't copy variables that are a pointer
if isinstance(arg.type, PointerType):
variable = RIALVariable(arg.name, rial_arg_types[i], arg)
else:
allocated_arg = self.builder.alloca(arg.type)
self.builder.store(arg, allocated_arg)
variable = RIALVariable(arg.name, rial_arg_types[i], allocated_arg)
self.current_block.add_named_value(arg.name, variable)
def finish_current_block(self):
if self.current_block.block.terminator is None:
self.builder.position_at_end(self.current_block.block)
self.builder.ret_void()
self.current_block = self.current_block.parent
def finish_current_func(self):
# If we're in release mode
# Reorder all possible allocas to the start of the function
if CompilationManager.config.raw_opts.release:
entry: Block = self.current_func.entry_basic_block
pos = entry.instructions.index(
next((instr for instr in reversed(entry.instructions) if isinstance(instr, AllocaInstr)),
entry.terminator))
allocas: List[Tuple[AllocaInstr, Block]] = list()
for block in self.current_func.blocks:
block: Block
# Skip first block
if block == entry:
continue
for instr in block.instructions:
if isinstance(instr, AllocaInstr):
allocas.append((instr, block))
for instr_block in allocas:
if instr_block is not None:
instr_block[1].instructions.remove(instr_block[0])
entry.instructions.insert(pos, instr_block[0])
pos += 1
# Insert nop if block is empty
if len(instr_block[1].instructions) == 0:
self.builder.position_before(instr_block[1].terminator)
self.gen_no_op()
self.current_func = None
def create_return_statement(self, statement=VoidType()):
if isinstance(statement, VoidType):
return self.builder.ret_void()
return self.builder.ret(statement)
def finish_loop(self):
self.conditional_block = None
self.end_block = None
def create_function_type(self, llvm_return_type: Type, llvm_arg_types: List[Type], var_args: bool):
return ir.FunctionType(llvm_return_type, tuple(llvm_arg_types), var_arg=var_args)
@contextmanager
def create_in_global_ctor(self):
current_block = self.current_block
current_func = self.current_func
current_struct = self.current_struct
conditional_block = self.conditional_block
end_block = self.end_block
pos = self.builder is not None and self.builder._anchor or 0
func = ParserState.module().get_global_safe('global_ctor')
if func is None:
func_type = self.create_function_type(ir.VoidType(), [], False)
func = self.create_function_with_type('global_ctor', 'global_ctor', func_type, "internal", "ccc",
FunctionDefinition('void'))
self.create_function_body(func, [])
struct_type = ir.LiteralStructType([ir.IntType(32), func_type.as_pointer(), ir.IntType(8).as_pointer()])
glob_value = ir.Constant(ir.ArrayType(struct_type, 1), [ir.Constant.literal_struct(
[ir.Constant(ir.IntType(32), 65535), func, NULL])])
glob_type = ir.ArrayType(struct_type, 1)
self.gen_global("llvm.global_ctors", glob_value, glob_type, RIALAccessModifier.PRIVATE, "appending", False)
else:
self.builder.position_before(func.entry_basic_block.terminator)
self.current_func = func
self.current_block = create_llvm_block(func.entry_basic_block)
self.current_struct = None
self.conditional_block = None
self.end_block = None
yield
self.finish_current_block()
self.finish_current_func()
self.current_block = current_block
self.current_func = current_func
self.current_struct = current_struct
self.conditional_block = conditional_block
self.end_block = end_block
self.builder._anchor = pos
self.builder._block = self.current_block is not None and self.current_block.block or None
return
