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all types are now expressions

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See #22
This commit is contained in:
Andrew Kelley
2016-01-13 18:15:51 -07:00
parent cb46d0b5b0
commit b28b7f63d1
26 changed files with 1632 additions and 1880 deletions
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355
src/codegen.cpp
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@@ -72,35 +72,35 @@ static LLVMValueRef gen_assign_raw(CodeGen *g, AstNode *source_node, BinOpType b
LLVMValueRef target_ref, LLVMValueRef value,
TypeTableEntry *op1_type, TypeTableEntry *op2_type);
static TypeTableEntry *get_type_for_type_node(CodeGen *g, AstNode *type_node) {
assert(type_node->type == NodeTypeType);
return type_node->data.type.entry;
static TypeTableEntry *get_type_for_type_node(AstNode *node) {
TypeTableEntry *meta_type_entry = get_resolved_expr(node)->type_entry;
assert(meta_type_entry->id == TypeTableEntryIdMetaType);
return meta_type_entry->data.meta_type.child_type;
}
static TypeTableEntry *fn_proto_type_from_type_node(CodeGen *g, AstNode *type_node) {
TypeTableEntry *type_entry = get_type_for_type_node(g, type_node);
TypeTableEntry *type_entry = get_type_for_type_node(type_node);
if (type_entry->id == TypeTableEntryIdStruct || type_entry->id == TypeTableEntryIdArray) {
return get_pointer_to_type(g, type_entry, true, true);
return get_pointer_to_type(g, type_entry, true);
} else {
return type_entry;
}
}
static LLVMZigDIType *to_llvm_debug_type(CodeGen *g, AstNode *type_node) {
TypeTableEntry *type_entry = get_type_for_type_node(g, type_node);
TypeTableEntry *type_entry = get_type_for_type_node(type_node);
return type_entry->di_type;
}
static bool type_is_unreachable(CodeGen *g, AstNode *type_node) {
return get_type_for_type_node(g, type_node)->id == TypeTableEntryIdUnreachable;
return get_type_for_type_node(type_node)->id == TypeTableEntryIdUnreachable;
}
static bool is_param_decl_type_void(CodeGen *g, AstNode *param_decl_node) {
assert(param_decl_node->type == NodeTypeParamDecl);
return get_type_for_type_node(g, param_decl_node->data.param_decl.type)->id == TypeTableEntryIdVoid;
return get_type_for_type_node(param_decl_node->data.param_decl.type)->id == TypeTableEntryIdVoid;
}
static int count_non_void_params(CodeGen *g, ZigList<AstNode *> *params) {
@@ -146,6 +146,32 @@ static TypeTableEntry *get_expr_type(AstNode *node) {
return expr->type_entry;
}
static LLVMValueRef gen_number_literal_raw(CodeGen *g, AstNode *source_node,
NumLitCodeGen *codegen_num_lit, AstNodeNumberLiteral *num_lit_node)
{
TypeTableEntry *type_entry = codegen_num_lit->resolved_type;
assert(type_entry);
// override the expression type for number literals
get_resolved_expr(source_node)->type_entry = type_entry;
if (type_entry->id == TypeTableEntryIdInt) {
// here the union has int64_t and uint64_t and we purposefully read
// the uint64_t value in either case, because we want the twos
// complement representation
return LLVMConstInt(type_entry->type_ref,
num_lit_node->data.x_uint,
type_entry->data.integral.is_signed);
} else if (type_entry->id == TypeTableEntryIdFloat) {
return LLVMConstReal(type_entry->type_ref,
num_lit_node->data.x_float);
} else {
zig_panic("bad number literal type");
}
}
static LLVMValueRef gen_builtin_fn_call_expr(CodeGen *g, AstNode *node) {
assert(node->type == NodeTypeFnCallExpr);
AstNode *fn_ref_expr = node->data.fn_call_expr.fn_ref_expr;
@@ -154,6 +180,7 @@ static LLVMValueRef gen_builtin_fn_call_expr(CodeGen *g, AstNode *node) {
switch (builtin_fn->id) {
case BuiltinFnIdInvalid:
case BuiltinFnIdTypeof:
zig_unreachable();
case BuiltinFnIdArithmeticWithOverflow:
{
@@ -238,6 +265,74 @@ static LLVMValueRef gen_builtin_fn_call_expr(CodeGen *g, AstNode *node) {
LLVMBuildCall(g->builder, builtin_fn->fn_val, params, 5, "");
return nullptr;
}
case BuiltinFnIdSizeof:
{
assert(node->data.fn_call_expr.params.length == 1);
AstNode *type_node = node->data.fn_call_expr.params.at(0);
TypeTableEntry *type_entry = get_type_for_type_node(type_node);
NumLitCodeGen *codegen_num_lit = get_resolved_num_lit(node);
AstNodeNumberLiteral num_lit_node;
num_lit_node.kind = NumLitU64; // this field isn't even read
num_lit_node.overflow = false;
num_lit_node.data.x_uint = type_entry->size_in_bits / 8;
return gen_number_literal_raw(g, node, codegen_num_lit, &num_lit_node);
}
case BuiltinFnIdMinValue:
{
assert(node->data.fn_call_expr.params.length == 1);
AstNode *type_node = node->data.fn_call_expr.params.at(0);
TypeTableEntry *type_entry = get_type_for_type_node(type_node);
if (type_entry->id == TypeTableEntryIdInt) {
if (type_entry->data.integral.is_signed) {
return LLVMConstInt(type_entry->type_ref, 1ULL << (type_entry->size_in_bits - 1), false);
} else {
return LLVMConstNull(type_entry->type_ref);
}
} else if (type_entry->id == TypeTableEntryIdFloat) {
zig_panic("TODO codegen min_value float");
} else {
zig_unreachable();
}
}
case BuiltinFnIdMaxValue:
{
assert(node->data.fn_call_expr.params.length == 1);
AstNode *type_node = node->data.fn_call_expr.params.at(0);
TypeTableEntry *type_entry = get_type_for_type_node(type_node);
if (type_entry->id == TypeTableEntryIdInt) {
if (type_entry->data.integral.is_signed) {
return LLVMConstInt(type_entry->type_ref, (1ULL << (type_entry->size_in_bits - 1)) - 1, false);
} else {
return LLVMConstAllOnes(type_entry->type_ref);
}
} else if (type_entry->id == TypeTableEntryIdFloat) {
zig_panic("TODO codegen max_value float");
} else {
zig_unreachable();
}
}
case BuiltinFnIdValueCount:
{
assert(node->data.fn_call_expr.params.length == 1);
AstNode *type_node = node->data.fn_call_expr.params.at(0);
TypeTableEntry *type_entry = get_type_for_type_node(type_node);
if (type_entry->id == TypeTableEntryIdEnum) {
NumLitCodeGen *codegen_num_lit = get_resolved_num_lit(node);
AstNodeNumberLiteral num_lit_node;
num_lit_node.kind = NumLitU64; // field ignored
num_lit_node.overflow = false;
num_lit_node.data.x_uint = type_entry->data.enumeration.field_count;
return gen_number_literal_raw(g, node, codegen_num_lit, &num_lit_node);
} else {
zig_unreachable();
}
}
}
zig_unreachable();
}
@@ -692,6 +787,10 @@ static LLVMValueRef gen_prefix_op_expr(CodeGen *g, AstNode *node) {
add_debug_source_node(g, node);
return LLVMBuildLoad(g->builder, expr, "");
}
case PrefixOpMaybe:
{
zig_panic("TODO codegen PrefixOpMaybe");
}
}
zig_unreachable();
}
@@ -1484,35 +1583,46 @@ static LLVMValueRef gen_null_literal(CodeGen *g, AstNode *node) {
return tmp_struct_ptr;
}
static LLVMValueRef gen_struct_val_expr(CodeGen *g, AstNode *node) {
assert(node->type == NodeTypeStructValueExpr);
static LLVMValueRef gen_container_init_expr(CodeGen *g, AstNode *node) {
assert(node->type == NodeTypeContainerInitExpr);
TypeTableEntry *type_entry = get_expr_type(node);
assert(type_entry->id == TypeTableEntryIdStruct);
if (type_entry->id == TypeTableEntryIdStruct) {
assert(node->data.container_init_expr.kind == ContainerInitKindStruct);
int field_count = type_entry->data.structure.field_count;
assert(field_count == node->data.struct_val_expr.fields.length);
int field_count = type_entry->data.structure.field_count;
assert(field_count == node->data.container_init_expr.entries.length);
StructValExprCodeGen *struct_val_expr_node = &node->data.struct_val_expr.codegen;
LLVMValueRef tmp_struct_ptr = struct_val_expr_node->ptr;
StructValExprCodeGen *struct_val_expr_node = &node->data.container_init_expr.resolved_struct_val_expr;
LLVMValueRef tmp_struct_ptr = struct_val_expr_node->ptr;
for (int i = 0; i < field_count; i += 1) {
AstNode *field_node = node->data.struct_val_expr.fields.at(i);
assert(field_node->type == NodeTypeStructValueField);
TypeStructField *type_struct_field = field_node->data.struct_val_field.type_struct_field;
if (type_struct_field->type_entry->id == TypeTableEntryIdVoid) {
continue;
for (int i = 0; i < field_count; i += 1) {
AstNode *field_node = node->data.container_init_expr.entries.at(i);
assert(field_node->type == NodeTypeStructValueField);
TypeStructField *type_struct_field = field_node->data.struct_val_field.type_struct_field;
if (type_struct_field->type_entry->id == TypeTableEntryIdVoid) {
continue;
}
assert(buf_eql_buf(type_struct_field->name, &field_node->data.struct_val_field.name));
add_debug_source_node(g, field_node);
LLVMValueRef field_ptr = LLVMBuildStructGEP(g->builder, tmp_struct_ptr, type_struct_field->gen_index, "");
LLVMValueRef value = gen_expr(g, field_node->data.struct_val_field.expr);
LLVMBuildStore(g->builder, value, field_ptr);
}
assert(buf_eql_buf(type_struct_field->name, &field_node->data.struct_val_field.name));
add_debug_source_node(g, field_node);
LLVMValueRef field_ptr = LLVMBuildStructGEP(g->builder, tmp_struct_ptr, type_struct_field->gen_index, "");
LLVMValueRef value = gen_expr(g, field_node->data.struct_val_field.expr);
LLVMBuildStore(g->builder, value, field_ptr);
return tmp_struct_ptr;
} else if (type_entry->id == TypeTableEntryIdUnreachable) {
assert(node->data.container_init_expr.entries.length == 0);
add_debug_source_node(g, node);
return LLVMBuildUnreachable(g->builder);
} else if (type_entry->id == TypeTableEntryIdVoid) {
assert(node->data.container_init_expr.entries.length == 0);
return nullptr;
} else {
zig_unreachable();
}
return tmp_struct_ptr;
}
static LLVMValueRef gen_while_expr(CodeGen *g, AstNode *node) {
@@ -1659,84 +1769,6 @@ static LLVMValueRef gen_var_decl_expr(CodeGen *g, AstNode *node) {
get_resolved_expr(node)->block_context, false, &init_val);
}
static LLVMValueRef gen_number_literal_raw(CodeGen *g, AstNode *source_node,
NumLitCodeGen *codegen_num_lit, AstNodeNumberLiteral *num_lit_node)
{
TypeTableEntry *type_entry = codegen_num_lit->resolved_type;
assert(type_entry);
// override the expression type for number literals
get_resolved_expr(source_node)->type_entry = type_entry;
if (type_entry->id == TypeTableEntryIdInt) {
// here the union has int64_t and uint64_t and we purposefully read
// the uint64_t value in either case, because we want the twos
// complement representation
return LLVMConstInt(type_entry->type_ref,
num_lit_node->data.x_uint,
type_entry->data.integral.is_signed);
} else if (type_entry->id == TypeTableEntryIdFloat) {
return LLVMConstReal(type_entry->type_ref,
num_lit_node->data.x_float);
} else {
zig_panic("bad number literal type");
}
}
static LLVMValueRef gen_compiler_fn_type(CodeGen *g, AstNode *node) {
assert(node->type == NodeTypeCompilerFnType);
Buf *name = &node->data.compiler_fn_type.name;
TypeTableEntry *type_entry = get_type_for_type_node(g, node->data.compiler_fn_type.type);
if (buf_eql_str(name, "sizeof")) {
NumLitCodeGen *codegen_num_lit = get_resolved_num_lit(node);
AstNodeNumberLiteral num_lit_node;
num_lit_node.kind = type_entry->data.num_lit.kind;
num_lit_node.overflow = false;
num_lit_node.data.x_uint = type_entry->size_in_bits / 8;
return gen_number_literal_raw(g, node, codegen_num_lit, &num_lit_node);
} else if (buf_eql_str(name, "min_value")) {
if (type_entry->id == TypeTableEntryIdInt) {
if (type_entry->data.integral.is_signed) {
return LLVMConstInt(type_entry->type_ref, 1ULL << (type_entry->size_in_bits - 1), false);
} else {
return LLVMConstNull(type_entry->type_ref);
}
} else if (type_entry->id == TypeTableEntryIdFloat) {
zig_panic("TODO codegen min_value float");
} else {
zig_unreachable();
}
} else if (buf_eql_str(name, "max_value")) {
if (type_entry->id == TypeTableEntryIdInt) {
if (type_entry->data.integral.is_signed) {
return LLVMConstInt(type_entry->type_ref, (1ULL << (type_entry->size_in_bits - 1)) - 1, false);
} else {
return LLVMConstAllOnes(type_entry->type_ref);
}
} else if (type_entry->id == TypeTableEntryIdFloat) {
zig_panic("TODO codegen max_value float");
} else {
zig_unreachable();
}
} else if (buf_eql_str(name, "value_count")) {
if (type_entry->id == TypeTableEntryIdEnum) {
NumLitCodeGen *codegen_num_lit = get_resolved_num_lit(node);
AstNodeNumberLiteral num_lit_node;
num_lit_node.kind = type_entry->data.num_lit.kind;
num_lit_node.overflow = false;
num_lit_node.data.x_uint = type_entry->data.enumeration.field_count;
return gen_number_literal_raw(g, node, codegen_num_lit, &num_lit_node);
} else {
zig_unreachable();
}
} else {
zig_unreachable();
}
}
static LLVMValueRef gen_number_literal(CodeGen *g, AstNode *node) {
assert(node->type == NodeTypeNumberLiteral);
@@ -1746,6 +1778,30 @@ static LLVMValueRef gen_number_literal(CodeGen *g, AstNode *node) {
return gen_number_literal_raw(g, node, codegen_num_lit, &node->data.number_literal);
}
static LLVMValueRef gen_symbol(CodeGen *g, AstNode *node) {
VariableTableEntry *variable = find_variable(
get_resolved_expr(node)->block_context,
&node->data.symbol_expr.symbol);
assert(variable);
if (variable->type->id == TypeTableEntryIdVoid) {
return nullptr;
} else if (variable->is_ptr) {
assert(variable->value_ref);
if (variable->type->id == TypeTableEntryIdArray) {
return variable->value_ref;
} else if (variable->type->id == TypeTableEntryIdStruct ||
variable->type->id == TypeTableEntryIdMaybe)
{
return variable->value_ref;
} else {
add_debug_source_node(g, node);
return LLVMBuildLoad(g->builder, variable->value_ref, "");
}
} else {
return variable->value_ref;
}
}
static LLVMValueRef gen_expr_no_cast(CodeGen *g, AstNode *node) {
switch (node->type) {
case NodeTypeBinOpExpr:
@@ -1766,11 +1822,6 @@ static LLVMValueRef gen_expr_no_cast(CodeGen *g, AstNode *node) {
return gen_slice_expr(g, node);
case NodeTypeFieldAccessExpr:
return gen_field_access_expr(g, node, false);
case NodeTypeUnreachable:
add_debug_source_node(g, node);
return LLVMBuildUnreachable(g->builder);
case NodeTypeVoid:
return nullptr;
case NodeTypeBoolLiteral:
if (node->data.bool_literal.value)
return LLVMConstAllOnes(LLVMInt1Type());
@@ -1802,29 +1853,7 @@ static LLVMValueRef gen_expr_no_cast(CodeGen *g, AstNode *node) {
case NodeTypeCharLiteral:
return LLVMConstInt(LLVMInt8Type(), node->data.char_literal.value, false);
case NodeTypeSymbol:
{
VariableTableEntry *variable = find_variable(
get_resolved_expr(node)->block_context,
&node->data.symbol_expr.symbol);
assert(variable);
if (variable->type->id == TypeTableEntryIdVoid) {
return nullptr;
} else if (variable->is_ptr) {
assert(variable->value_ref);
if (variable->type->id == TypeTableEntryIdArray) {
return variable->value_ref;
} else if (variable->type->id == TypeTableEntryIdStruct ||
variable->type->id == TypeTableEntryIdMaybe)
{
return variable->value_ref;
} else {
add_debug_source_node(g, node);
return LLVMBuildLoad(g->builder, variable->value_ref, "");
}
} else {
return variable->value_ref;
}
}
return gen_symbol(g, node);
case NodeTypeBlock:
return gen_block(g, node, nullptr);
case NodeTypeGoto:
@@ -1846,24 +1875,21 @@ static LLVMValueRef gen_expr_no_cast(CodeGen *g, AstNode *node) {
LLVMPositionBuilderAtEnd(g->builder, basic_block);
return nullptr;
}
case NodeTypeStructValueExpr:
return gen_struct_val_expr(g, node);
case NodeTypeCompilerFnType:
return gen_compiler_fn_type(g, node);
case NodeTypeContainerInitExpr:
return gen_container_init_expr(g, node);
case NodeTypeRoot:
case NodeTypeRootExportDecl:
case NodeTypeFnProto:
case NodeTypeFnDef:
case NodeTypeFnDecl:
case NodeTypeParamDecl:
case NodeTypeType:
case NodeTypeExternBlock:
case NodeTypeDirective:
case NodeTypeUse:
case NodeTypeStructDecl:
case NodeTypeStructField:
case NodeTypeStructValueField:
case NodeTypeCompilerFnExpr:
case NodeTypeArrayType:
zig_unreachable();
}
zig_unreachable();
@@ -1872,7 +1898,7 @@ static LLVMValueRef gen_expr_no_cast(CodeGen *g, AstNode *node) {
static LLVMValueRef gen_expr(CodeGen *g, AstNode *node) {
LLVMValueRef val = gen_expr_no_cast(g, node);
if (node->type == NodeTypeVoid) {
if (is_node_void_expr(node)) {
return val;
}
@@ -1966,7 +1992,7 @@ static void do_code_gen(CodeGen *g) {
assert(proto_node->type == NodeTypeFnProto);
AstNodeFnProto *fn_proto = &proto_node->data.fn_proto;
LLVMTypeRef ret_type = get_type_for_type_node(g, fn_proto->return_type)->type_ref;
LLVMTypeRef ret_type = get_type_for_type_node(fn_proto->return_type)->type_ref;
int param_count = count_non_void_params(g, &fn_proto->params);
LLVMTypeRef *param_types = allocate<LLVMTypeRef>(param_count);
int gen_param_index = 0;
@@ -2009,7 +2035,7 @@ static void do_code_gen(CodeGen *g) {
TypeTableEntry *param_type = fn_proto_type_from_type_node(g, type_node);
LLVMValueRef argument_val = LLVMGetParam(fn, gen_param_index);
if (param_type->id == TypeTableEntryIdPointer &&
param_type->data.pointer.is_noalias)
false) // TODO test if parameter is noalias
{
LLVMAddAttribute(argument_val, LLVMNoAliasAttribute);
} else if (param_type->id == TypeTableEntryIdPointer &&
@@ -2267,7 +2293,7 @@ static void define_builtin_types(CodeGen *g) {
g->builtin_types.entry_u64 = entry;
g->primitive_type_table.put(&entry->name, entry);
}
g->builtin_types.entry_c_string_literal = get_pointer_to_type(g, g->builtin_types.entry_u8, true, false);
g->builtin_types.entry_c_string_literal = get_pointer_to_type(g, g->builtin_types.entry_u8, true);
{
TypeTableEntry *entry = new_type_table_entry(TypeTableEntryIdInt);
entry->type_ref = LLVMInt8Type();
@@ -2413,7 +2439,7 @@ static void define_builtin_fns_int(CodeGen *g, TypeTableEntry *type_entry) {
builtin_fn->param_types = allocate<TypeTableEntry *>(builtin_fn->param_count);
builtin_fn->param_types[0] = type_entry;
builtin_fn->param_types[1] = type_entry;
builtin_fn->param_types[2] = get_pointer_to_type(g, type_entry, false, false);
builtin_fn->param_types[2] = get_pointer_to_type(g, type_entry, false);
const char *signed_str = type_entry->data.integral.is_signed ?
@@ -2437,6 +2463,23 @@ static void define_builtin_fns_int(CodeGen *g, TypeTableEntry *type_entry) {
}
}
static BuiltinFnEntry *create_builtin_fn(CodeGen *g, BuiltinFnId id, const char *name) {
BuiltinFnEntry *builtin_fn = allocate<BuiltinFnEntry>(1);
buf_init_from_str(&builtin_fn->name, name);
builtin_fn->id = id;
g->builtin_fn_table.put(&builtin_fn->name, builtin_fn);
return builtin_fn;
}
static BuiltinFnEntry *create_one_arg_builtin_fn(CodeGen *g, BuiltinFnId id, const char *name) {
BuiltinFnEntry *builtin_fn = create_builtin_fn(g, id, name);
builtin_fn->return_type = nullptr; // manually determined later
builtin_fn->param_count = 1;
builtin_fn->param_types = allocate<TypeTableEntry *>(builtin_fn->param_count);
builtin_fn->param_types[0] = nullptr; // manually checked later
return builtin_fn;
}
static void define_builtin_fns(CodeGen *g) {
define_builtin_fns_int(g, g->builtin_types.entry_u8);
define_builtin_fns_int(g, g->builtin_types.entry_u16);
@@ -2447,9 +2490,7 @@ static void define_builtin_fns(CodeGen *g) {
define_builtin_fns_int(g, g->builtin_types.entry_i32);
define_builtin_fns_int(g, g->builtin_types.entry_i64);
{
BuiltinFnEntry *builtin_fn = allocate<BuiltinFnEntry>(1);
buf_init_from_str(&builtin_fn->name, "memcpy");
builtin_fn->id = BuiltinFnIdMemcpy;
BuiltinFnEntry *builtin_fn = create_builtin_fn(g, BuiltinFnIdMemcpy, "memcpy");
builtin_fn->return_type = g->builtin_types.entry_void;
builtin_fn->param_count = 3;
builtin_fn->param_types = allocate<TypeTableEntry *>(builtin_fn->param_count);
@@ -2470,12 +2511,9 @@ static void define_builtin_fns(CodeGen *g) {
assert(LLVMGetIntrinsicID(builtin_fn->fn_val));
g->memcpy_fn_val = builtin_fn->fn_val;
g->builtin_fn_table.put(&builtin_fn->name, builtin_fn);
}
{
BuiltinFnEntry *builtin_fn = allocate<BuiltinFnEntry>(1);
buf_init_from_str(&builtin_fn->name, "memset");
builtin_fn->id = BuiltinFnIdMemset;
BuiltinFnEntry *builtin_fn = create_builtin_fn(g, BuiltinFnIdMemset, "memset");
builtin_fn->return_type = g->builtin_types.entry_void;
builtin_fn->param_count = 3;
builtin_fn->param_types = allocate<TypeTableEntry *>(builtin_fn->param_count);
@@ -2496,8 +2534,12 @@ static void define_builtin_fns(CodeGen *g) {
assert(LLVMGetIntrinsicID(builtin_fn->fn_val));
g->memset_fn_val = builtin_fn->fn_val;
g->builtin_fn_table.put(&builtin_fn->name, builtin_fn);
}
create_one_arg_builtin_fn(g, BuiltinFnIdSizeof, "sizeof");
create_one_arg_builtin_fn(g, BuiltinFnIdMaxValue, "max_value");
create_one_arg_builtin_fn(g, BuiltinFnIdMinValue, "min_value");
create_one_arg_builtin_fn(g, BuiltinFnIdValueCount, "value_count");
create_one_arg_builtin_fn(g, BuiltinFnIdTypeof, "typeof");
}
@@ -2780,9 +2822,8 @@ void codegen_add_root_code(CodeGen *g, Buf *src_dir, Buf *src_basename, Buf *sou
}
static void to_c_type(CodeGen *g, AstNode *type_node, Buf *out_buf) {
assert(type_node->type == NodeTypeType);
TypeTableEntry *type_entry = type_node->data.type.entry;
zig_panic("TODO this function needs some love");
TypeTableEntry *type_entry = get_resolved_expr(type_node)->type_entry;
assert(type_entry);
if (type_entry == g->builtin_types.entry_u8) {