authorgravatar for scurest@users.noreply.github.comscurest <scurest@users.noreply.github.com> 2017-06-17 11:30:29-05:00
committergravatar for andrew@ziglang.orgAndrew Kelley <andrew@ziglang.org> 2017-08-26 13:48:16-04:00
log5bc877017ede3b85361a112987757ee277b9c889
tree1403967c72b47399b0d2f796922007e350d14dda
parente726925e802eddab53cbfd9aacbc5eefe95c356f

use most_aligned_member+padding to represent enum unions

4 files changed, 52 insertions(+), 21 deletions(-)

src/all_types.hpp+2-2
......@@ -977,7 +977,7 @@ struct TypeTableEntryEnum {
977977 TypeEnumField *fields;
978978 bool is_invalid; // true if any fields are invalid
979979 TypeTableEntry *tag_type;
980 TypeTableEntry *union_type;
980 LLVMTypeRef union_type_ref;
981981
982982 ScopeDecls *decls_scope;
983983
......@@ -1633,7 +1633,7 @@ struct ScopeDecls {
16331633struct ScopeBlock {
16341634 Scope base;
16351635
1636 HashMap<Buf *, LabelTableEntry *, buf_hash, buf_eql_buf> label_table;
1636 HashMap<Buf *, LabelTableEntry *, buf_hash, buf_eql_buf> label_table;
16371637 bool safety_off;
16381638 AstNode *safety_set_node;
16391639 bool fast_math_off;
src/analyze.cpp+36-16
......@@ -1245,9 +1245,10 @@ static void resolve_enum_type(CodeGen *g, TypeTableEntry *enum_type) {
12451245 uint32_t gen_field_count = enum_type->data.enumeration.gen_field_count;
12461246 ZigLLVMDIType **union_inner_di_types = allocate<ZigLLVMDIType*>(gen_field_count);
12471247
1248 TypeTableEntry *biggest_union_member = nullptr;
1248 TypeTableEntry *most_aligned_union_member = nullptr;
1249 uint64_t size_of_most_aligned_member_in_bits = 0;
12491250 uint64_t biggest_align_in_bits = 0;
1250 uint64_t biggest_union_member_size_in_bits = 0;
1251 uint64_t biggest_size_in_bits = 0;
12511252
12521253 Scope *scope = &enum_type->data.enumeration.decls_scope->base;
12531254 ImportTableEntry *import = get_scope_import(scope);
......@@ -1272,7 +1273,7 @@ static void resolve_enum_type(CodeGen *g, TypeTableEntry *enum_type) {
12721273 continue;
12731274
12741275 uint64_t debug_size_in_bits = 8*LLVMStoreSizeOfType(g->target_data_ref, field_type->type_ref);
1275 uint64_t debug_align_in_bits = 8*LLVMABISizeOfType(g->target_data_ref, field_type->type_ref);
1276 uint64_t debug_align_in_bits = 8*LLVMABIAlignmentOfType(g->target_data_ref, field_type->type_ref);
12761277
12771278 assert(debug_size_in_bits > 0);
12781279 assert(debug_align_in_bits > 0);
......@@ -1285,13 +1286,14 @@ static void resolve_enum_type(CodeGen *g, TypeTableEntry *enum_type) {
12851286 0,
12861287 0, field_type->di_type);
12871288
1288 biggest_align_in_bits = max(biggest_align_in_bits, debug_align_in_bits);
1289 biggest_size_in_bits = max(biggest_size_in_bits, debug_size_in_bits);
12891290
1290 if (!biggest_union_member ||
1291 debug_size_in_bits > biggest_union_member_size_in_bits)
1291 if (!most_aligned_union_member ||
1292 debug_align_in_bits > biggest_align_in_bits)
12921293 {
1293 biggest_union_member = field_type;
1294 biggest_union_member_size_in_bits = debug_size_in_bits;
1294 most_aligned_union_member = field_type;
1295 biggest_align_in_bits = debug_align_in_bits;
1296 size_of_most_aligned_member_in_bits = debug_size_in_bits;
12951297 }
12961298 }
12971299
......@@ -1300,16 +1302,34 @@ static void resolve_enum_type(CodeGen *g, TypeTableEntry *enum_type) {
13001302 enum_type->data.enumeration.complete = true;
13011303
13021304 if (!enum_type->data.enumeration.is_invalid) {
1303 enum_type->data.enumeration.union_type = biggest_union_member;
1304
13051305 TypeTableEntry *tag_int_type = get_smallest_unsigned_int_type(g, field_count);
13061306 TypeTableEntry *tag_type_entry = create_enum_tag_type(g, enum_type, tag_int_type);
13071307 enum_type->data.enumeration.tag_type = tag_type_entry;
13081308
1309 if (biggest_union_member) {
1309 if (most_aligned_union_member) {
13101310 // create llvm type for union
1311 LLVMTypeRef union_element_type = biggest_union_member->type_ref;
1312 LLVMTypeRef union_type_ref = LLVMStructType(&union_element_type, 1, false);
1311 uint64_t padding_in_bits = biggest_size_in_bits - size_of_most_aligned_member_in_bits;
1312 LLVMTypeRef union_type_ref;
1313 if (padding_in_bits > 0) {
1314 TypeTableEntry *u8_type = get_int_type(g, false, 8);
1315 TypeTableEntry *padding_array = get_array_type(g, u8_type, padding_in_bits / 8);
1316 LLVMTypeRef union_element_types[] = {
1317 most_aligned_union_member->type_ref,
1318 padding_array->type_ref,
1319 };
1320 union_type_ref = LLVMStructType(union_element_types, 2, false);
1321 } else {
1322 LLVMTypeRef union_element_types[] = {
1323 most_aligned_union_member->type_ref,
1324 };
1325 union_type_ref = LLVMStructType(union_element_types, 1, false);
1326 }
1327 enum_type->data.enumeration.union_type_ref = union_type_ref;
1328
1329 assert(8*LLVMABIAlignmentOfType(g->target_data_ref, union_type_ref) >=
1330 biggest_align_in_bits);
1331 assert(8*LLVMABISizeOfType(g->target_data_ref, union_type_ref) >=
1332 biggest_size_in_bits);
13131333
13141334 // create llvm type for root struct
13151335 LLVMTypeRef root_struct_element_types[] = {
......@@ -1331,7 +1351,7 @@ static void resolve_enum_type(CodeGen *g, TypeTableEntry *enum_type) {
13311351 ZigLLVMDIType *union_di_type = ZigLLVMCreateDebugUnionType(g->dbuilder,
13321352 ZigLLVMTypeToScope(enum_type->di_type), "AnonUnion",
13331353 import->di_file, (unsigned)(decl_node->line + 1),
1334 biggest_union_member_size_in_bits, biggest_align_in_bits, 0, union_inner_di_types,
1354 biggest_size_in_bits, biggest_align_in_bits, 0, union_inner_di_types,
13351355 gen_field_count, 0, "");
13361356
13371357 // create debug types for members of root struct
......@@ -1348,7 +1368,7 @@ static void resolve_enum_type(CodeGen *g, TypeTableEntry *enum_type) {
13481368 ZigLLVMDIType *union_member_di_type = ZigLLVMCreateDebugMemberType(g->dbuilder,
13491369 ZigLLVMTypeToScope(enum_type->di_type), "union_field",
13501370 import->di_file, (unsigned)(decl_node->line + 1),
1351 biggest_union_member_size_in_bits,
1371 biggest_size_in_bits,
13521372 biggest_align_in_bits,
13531373 union_offset_in_bits,
13541374 0, union_di_type);
......@@ -2541,7 +2561,7 @@ bool types_match_const_cast_only(TypeTableEntry *expected_type, TypeTableEntry *
25412561 if (expected_type->data.fn.is_generic != actual_type->data.fn.is_generic) {
25422562 return false;
25432563 }
2544 if (!expected_type->data.fn.is_generic &&
2564 if (!expected_type->data.fn.is_generic &&
25452565 actual_type->data.fn.fn_type_id.return_type->id != TypeTableEntryIdUnreachable &&
25462566 !types_match_const_cast_only(
25472567 expected_type->data.fn.fn_type_id.return_type,
src/codegen.cpp+3-3
......@@ -3663,13 +3663,13 @@ static LLVMValueRef gen_const_val(CodeGen *g, ConstExprValue *const_val) {
36633663 if (type_entry->data.enumeration.gen_field_count == 0) {
36643664 return tag_value;
36653665 } else {
3666 TypeTableEntry *union_type = type_entry->data.enumeration.union_type;
3666 LLVMTypeRef union_type_ref = type_entry->data.enumeration.union_type_ref;
36673667 TypeEnumField *enum_field = &type_entry->data.enumeration.fields[const_val->data.x_enum.tag];
36683668 assert(enum_field->value == const_val->data.x_enum.tag);
36693669 LLVMValueRef union_value;
36703670 if (type_has_bits(enum_field->type_entry)) {
36713671 uint64_t union_type_bytes = LLVMStoreSizeOfType(g->target_data_ref,
3672 union_type->type_ref);
3672 union_type_ref);
36733673 uint64_t field_type_bytes = LLVMStoreSizeOfType(g->target_data_ref,
36743674 enum_field->type_entry->type_ref);
36753675 uint64_t pad_bytes = union_type_bytes - field_type_bytes;
......@@ -3685,7 +3685,7 @@ static LLVMValueRef gen_const_val(CodeGen *g, ConstExprValue *const_val) {
36853685 union_value = LLVMConstStruct(fields, 2, false);
36863686 }
36873687 } else {
3688 union_value = LLVMGetUndef(union_type->type_ref);
3688 union_value = LLVMGetUndef(union_type_ref);
36893689 }
36903690 LLVMValueRef fields[] = {
36913691 tag_value,
test/cases/enum.zig+11
......@@ -120,3 +120,14 @@ const BareNumber = enum {
120120 Two,
121121 Three,
122122};
123
124
125test "enum alignment" {
126 comptime assert(@alignOf(AlignTestEnum) >= @alignOf([9]u8));
127 comptime assert(@alignOf(AlignTestEnum) >= @alignOf(u64));
128}
129
130const AlignTestEnum = enum {
131 A: [9]u8,
132 B: u64,
133};