Ekdohibs
/
zig
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

implement null as a literal type

master
Andrew Kelley 2016-08-25 17:25:18 -07:00
parent 1f7ec741fa
commit 651dc31247
8 changed files with 76 additions and 35 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

1
CMakeLists.txt
View File

@ -202,6 +202,7 @@ install(FILES "${CMAKE_SOURCE_DIR}/std/builtin.zig" DESTINATION "${ZIG_STD_DEST}
install(FILES "${CMAKE_SOURCE_DIR}/std/compiler_rt.zig" DESTINATION "${ZIG_STD_DEST}")
install(FILES "${CMAKE_SOURCE_DIR}/std/cstr.zig" DESTINATION "${ZIG_STD_DEST}")
install(FILES "${CMAKE_SOURCE_DIR}/std/debug.zig" DESTINATION "${ZIG_STD_DEST}")
install(FILES "${CMAKE_SOURCE_DIR}/std/dwarf.zig" DESTINATION "${ZIG_STD_DEST}")
install(FILES "${CMAKE_SOURCE_DIR}/std/elf.zig" DESTINATION "${ZIG_STD_DEST}")
install(FILES "${CMAKE_SOURCE_DIR}/std/empty.zig" DESTINATION "${ZIG_STD_DEST}")
install(FILES "${CMAKE_SOURCE_DIR}/std/endian.zig" DESTINATION "${ZIG_STD_DEST}")

6
src/all_types.hpp
View File

@ -394,6 +394,7 @@ enum CastOp {
CastOpWidenOrShorten,
CastOpToUnknownSizeArray,
CastOpMaybeWrap,
CastOpNullToMaybe,
CastOpErrorWrap,
CastOpPureErrorWrap,
CastOpPointerReinterpret,
@ -692,19 +693,16 @@ struct AstNodeContainerInitExpr {
struct AstNodeNullLiteral {
// populated by semantic analyzer
StructValExprCodeGen resolved_struct_val_expr;
Expr resolved_expr;
};
struct AstNodeUndefinedLiteral {
// populated by semantic analyzer
StructValExprCodeGen resolved_struct_val_expr;
Expr resolved_expr;
};
struct AstNodeZeroesLiteral {
// populated by semantic analyzer
StructValExprCodeGen resolved_struct_val_expr;
Expr resolved_expr;
};
@ -989,6 +987,7 @@ enum TypeTableEntryId {
TypeTableEntryIdNumLitFloat,
TypeTableEntryIdNumLitInt,
TypeTableEntryIdUndefLit,
TypeTableEntryIdNullLit,
TypeTableEntryIdMaybe,
TypeTableEntryIdErrorUnion,
TypeTableEntryIdPureError,
@ -1228,6 +1227,7 @@ struct CodeGen {
TypeTableEntry *entry_num_lit_int;
TypeTableEntry *entry_num_lit_float;
TypeTableEntry *entry_undef;
TypeTableEntry *entry_null;
TypeTableEntry *entry_pure_error;
TypeTableEntry *entry_os_enum;
TypeTableEntry *entry_arch_enum;

63
src/analyze.cpp
View File

@ -237,6 +237,7 @@ static bool type_is_complete(TypeTableEntry *type_entry) {
case TypeTableEntryIdNumLitFloat:
case TypeTableEntryIdNumLitInt:
case TypeTableEntryIdUndefLit:
case TypeTableEntryIdNullLit:
case TypeTableEntryIdMaybe:
case TypeTableEntryIdErrorUnion:
case TypeTableEntryIdPureError:
@ -925,6 +926,7 @@ static TypeTableEntry *analyze_fn_proto_type(CodeGen *g, ImportTableEntry *impor
case TypeTableEntryIdNumLitFloat:
case TypeTableEntryIdNumLitInt:
case TypeTableEntryIdUndefLit:
case TypeTableEntryIdNullLit:
case TypeTableEntryIdNamespace:
case TypeTableEntryIdGenericFn:
fn_proto->skip = true;
@ -963,6 +965,7 @@ static TypeTableEntry *analyze_fn_proto_type(CodeGen *g, ImportTableEntry *impor
case TypeTableEntryIdNumLitFloat:
case TypeTableEntryIdNumLitInt:
case TypeTableEntryIdUndefLit:
case TypeTableEntryIdNullLit:
case TypeTableEntryIdUnreachable:
case TypeTableEntryIdNamespace:
case TypeTableEntryIdGenericFn:
@ -1912,6 +1915,7 @@ static bool type_has_codegen_value(TypeTableEntry *type_entry) {
case TypeTableEntryIdNumLitFloat:
case TypeTableEntryIdNumLitInt:
case TypeTableEntryIdUndefLit:
case TypeTableEntryIdNullLit:
case TypeTableEntryIdNamespace:
case TypeTableEntryIdGenericFn:
return false;
@ -2167,6 +2171,13 @@ static bool types_match_with_implicit_cast(CodeGen *g, TypeTableEntry *expected_
return true;
}
// implicit conversion from null literal to maybe type
if (expected_type->id == TypeTableEntryIdMaybe &&
actual_type->id == TypeTableEntryIdNullLit)
{
return true;
}
// implicit conversion from error child type to error type
if (expected_type->id == TypeTableEntryIdErrorUnion &&
types_match_with_implicit_cast(g, expected_type->data.error.child_type, actual_type,
@ -2971,13 +2982,6 @@ static TypeTableEntry *resolve_expr_const_val_as_bool(CodeGen *g, AstNode *node,
return g->builtin_types.entry_bool;
}
static TypeTableEntry *resolve_expr_const_val_as_null(CodeGen *g, AstNode *node, TypeTableEntry *type) {
Expr *expr = get_resolved_expr(node);
expr->const_val.ok = true;
expr->const_val.data.x_maybe = nullptr;
return type;
}
static TypeTableEntry *resolve_expr_const_val_as_non_null(CodeGen *g, AstNode *node,
TypeTableEntry *type, ConstExprValue *other_val)
{
@ -3358,6 +3362,7 @@ static TypeTableEntry *analyze_bool_bin_op_expr(CodeGen *g, ImportTableEntry *im
case TypeTableEntryIdArray:
case TypeTableEntryIdStruct:
case TypeTableEntryIdUndefLit:
case TypeTableEntryIdNullLit:
case TypeTableEntryIdMaybe:
case TypeTableEntryIdErrorUnion:
case TypeTableEntryIdUnion:
@ -3916,26 +3921,17 @@ static TypeTableEntry *analyze_null_literal_expr(CodeGen *g, ImportTableEntry *i
{
assert(node->type == NodeTypeNullLiteral);
if (!expected_type) {
add_node_error(g, node, buf_sprintf("unable to determine null type"));
return g->builtin_types.entry_invalid;
}
ConstExprValue *const_val = &get_resolved_expr(node)->const_val;
const_val->ok = true;
if (expected_type->id != TypeTableEntryIdMaybe) {
add_node_error(g, node,
buf_sprintf("expected maybe type, got '%s'", buf_ptr(&expected_type->name)));
return g->builtin_types.entry_invalid;
}
node->data.null_literal.resolved_struct_val_expr.type_entry = expected_type;
node->data.null_literal.resolved_struct_val_expr.source_node = node;
return resolve_expr_const_val_as_null(g, node, expected_type);
return g->builtin_types.entry_null;
}
static TypeTableEntry *analyze_undefined_literal_expr(CodeGen *g, ImportTableEntry *import, BlockContext *context,
TypeTableEntry *expected_type, AstNode *node)
{
assert(node->type == NodeTypeUndefinedLiteral);
Expr *expr = get_resolved_expr(node);
ConstExprValue *const_val = &expr->const_val;
@ -4519,6 +4515,14 @@ static TypeTableEntry *analyze_cast_expr(CodeGen *g, ImportTableEntry *import, B
}
}
// explicit cast from null literal to maybe type
if (wanted_type->id == TypeTableEntryIdMaybe &&
actual_type->id == TypeTableEntryIdNullLit)
{
get_resolved_expr(node)->return_knowledge = ReturnKnowledgeKnownNull;
return resolve_cast(g, context, node, expr_node, wanted_type, CastOpNullToMaybe, true);
}
// explicit cast from child type of error type to error type
if (wanted_type->id == TypeTableEntryIdErrorUnion) {
if (types_match_const_cast_only(wanted_type->data.error.child_type, actual_type)) {
@ -5203,6 +5207,7 @@ static TypeTableEntry *analyze_builtin_fn_call_expr(CodeGen *g, ImportTableEntry
case TypeTableEntryIdNumLitFloat:
case TypeTableEntryIdNumLitInt:
case TypeTableEntryIdUndefLit:
case TypeTableEntryIdNullLit:
case TypeTableEntryIdNamespace:
case TypeTableEntryIdGenericFn:
add_node_error(g, expr_node,
@ -6252,13 +6257,12 @@ static TypeTableEntry *analyze_return_expr(CodeGen *g, ImportTableEntry *import,
if (resolved_type->id == TypeTableEntryIdInvalid) {
return resolved_type;
} else if (resolved_type->id == TypeTableEntryIdErrorUnion) {
TypeTableEntry *return_type = context->fn_entry->type_entry->data.fn.fn_type_id.return_type;
if (return_type->id != TypeTableEntryIdErrorUnion &&
return_type->id != TypeTableEntryIdPureError)
if (expected_return_type->id != TypeTableEntryIdErrorUnion &&
expected_return_type->id != TypeTableEntryIdPureError)
{
ErrorMsg *msg = add_node_error(g, node,
buf_sprintf("%%return statement in function with return type '%s'",
buf_ptr(&return_type->name)));
buf_ptr(&expected_return_type->name)));
AstNode *return_type_node = context->fn_entry->fn_def_node->data.fn_def.fn_proto->data.fn_proto.return_type;
add_error_note(g, msg, return_type_node, buf_sprintf("function return type here"));
}
@ -6283,11 +6287,10 @@ static TypeTableEntry *analyze_return_expr(CodeGen *g, ImportTableEntry *import,
if (resolved_type->id == TypeTableEntryIdInvalid) {
return resolved_type;
} else if (resolved_type->id == TypeTableEntryIdMaybe) {
TypeTableEntry *return_type = context->fn_entry->type_entry->data.fn.fn_type_id.return_type;
if (return_type->id != TypeTableEntryIdMaybe) {
if (expected_return_type->id != TypeTableEntryIdMaybe) {
ErrorMsg *msg = add_node_error(g, node,
buf_sprintf("?return statement in function with return type '%s'",
buf_ptr(&return_type->name)));
buf_ptr(&expected_return_type->name)));
AstNode *return_type_node = context->fn_entry->fn_def_node->data.fn_def.fn_proto->data.fn_proto.return_type;
add_error_note(g, msg, return_type_node, buf_sprintf("function return type here"));
}
@ -7227,6 +7230,7 @@ bool handle_is_ptr(TypeTableEntry *type_entry) {
case TypeTableEntryIdNumLitFloat:
case TypeTableEntryIdNumLitInt:
case TypeTableEntryIdUndefLit:
case TypeTableEntryIdNullLit:
case TypeTableEntryIdNamespace:
case TypeTableEntryIdGenericFn:
zig_unreachable();
@ -7335,6 +7339,8 @@ static uint32_t hash_const_val(TypeTableEntry *type, ConstExprValue *const_val)
return hash_ptr(const_val->data.x_ptr.ptr);
case TypeTableEntryIdUndefLit:
return 162837799;
case TypeTableEntryIdNullLit:
return 844854567;
case TypeTableEntryIdArray:
// TODO better hashing algorithm
return 1166190605;
@ -7428,6 +7434,7 @@ static TypeTableEntry *type_of_first_thing_in_memory(TypeTableEntry *type_entry)
case TypeTableEntryIdNumLitFloat:
case TypeTableEntryIdNumLitInt:
case TypeTableEntryIdUndefLit:
case TypeTableEntryIdNullLit:
case TypeTableEntryIdUnreachable:
case TypeTableEntryIdMetaType:
case TypeTableEntryIdVoid:

10
src/codegen.cpp
View File

@ -875,6 +875,9 @@ static LLVMValueRef gen_cast_expr(CodeGen *g, AstNode *node) {
return cast_expr->tmp_ptr;
}
case CastOpNullToMaybe:
// handled by constant expression evaluator
zig_unreachable();
case CastOpErrorWrap:
{
assert(wanted_type->id == TypeTableEntryIdErrorUnion);
@ -3806,6 +3809,7 @@ static LLVMValueRef gen_const_val(CodeGen *g, TypeTableEntry *type_entry, ConstE
case TypeTableEntryIdNumLitFloat:
case TypeTableEntryIdNumLitInt:
case TypeTableEntryIdUndefLit:
case TypeTableEntryIdNullLit:
case TypeTableEntryIdVoid:
case TypeTableEntryIdNamespace:
case TypeTableEntryIdGenericFn:
@ -4311,6 +4315,12 @@ static void define_builtin_types(CodeGen *g) {
entry->deep_const = true;
g->builtin_types.entry_undef = entry;
}
{
TypeTableEntry *entry = new_type_table_entry(TypeTableEntryIdNullLit);
buf_init_from_str(&entry->name, "(null)");
entry->deep_const = true;
g->builtin_types.entry_null = entry;
}
for (int int_size_i = 0; int_size_i < array_length(int_sizes_in_bits); int_size_i += 1) {
int size_in_bits = int_sizes_in_bits[int_size_i];

6
src/eval.cpp
View File

@ -45,6 +45,8 @@ bool const_values_equal(ConstExprValue *a, ConstExprValue *b, TypeTableEntry *ty
zig_panic("TODO");
case TypeTableEntryIdUndefLit:
zig_panic("TODO");
case TypeTableEntryIdNullLit:
zig_panic("TODO");
case TypeTableEntryIdMaybe:
zig_panic("TODO");
case TypeTableEntryIdErrorUnion:
@ -650,6 +652,10 @@ void eval_const_expr_implicit_cast(CastOp cast_op,
const_val->data.x_maybe = other_val;
const_val->ok = true;
break;
case CastOpNullToMaybe:
const_val->data.x_maybe = nullptr;
const_val->ok = true;
break;
case CastOpErrorWrap:
const_val->data.x_err.err = nullptr;
const_val->data.x_err.payload = other_val;

8
std/debug.zig
View File

@ -40,7 +40,7 @@ pub fn writeStackTrace(out_stream: &io.OutStream) -> %void {
%return out_stream.printInt(usize, return_address);
%return out_stream.printf(" -> ");
%return out_stream.printInt(u64, debug_info_offset);
%return out_stream.printInt(u64, compile_unit_offset);
%return out_stream.printf("\n");
maybe_fp = *(&const ?&const u8)(fp);
}
@ -82,7 +82,8 @@ fn findCompileUnitOffset(st: &ElfStackTrace, target_address: usize) -> %u64 {
}
fn arangesOffset(st: &ElfStackTrace, target_address: usize) -> %?u64 {
const aranges = ?return st.aranges;
// TODO ability to implicitly cast null to %?T
const aranges = st.aranges ?? return (?u64)(null);
%return st.elf.seekToSection(aranges);
@ -129,7 +130,8 @@ fn arangesOffset(st: &ElfStackTrace, target_address: usize) -> %?u64 {
if (address == 0 && length == 0) break;
if (target_address >= address && target_address < address + length) {
return debug_info_offset;
// TODO ability to implicitly cast T to %?T
return (?u64)(debug_info_offset);
}
}
}

15
test/cases/maybe_return.zig Normal file
View File

@ -0,0 +1,15 @@
const assert = @import("std").debug.assert;
#attribute("test")
fn maybeReturn() {
assert(??foo(1235));
assert(if (const _ ?= foo(null)) false else true);
assert(!??foo(1234));
}
// TODO add another function with static_eval_enable(true)
#static_eval_enable(false)
fn foo(x: ?i32) -> ?bool {
const value = ?return x;
return value > 1234;
}

2
test/run_tests.cpp
View File

@ -1211,7 +1211,7 @@ fn derp(){}
add_compile_fail_case("assign null to non-nullable pointer", R"SOURCE(
const a: &u8 = null;
)SOURCE", 1, ".tmp_source.zig:2:16: error: expected maybe type, got '&u8'");
)SOURCE", 1, ".tmp_source.zig:2:16: error: expected type '&u8', got '(null)'");
add_compile_fail_case("indexing an array of size zero", R"SOURCE(
const array = []u8{};