authorgravatar for andrew@ziglang.orgAndrew Kelley <andrew@ziglang.org> 2018-09-21 14:16:14-04:00
committergravatar for andrew@ziglang.orgAndrew Kelley <andrew@ziglang.org> 2018-09-21 14:16:14-04:00
log0ca12ded2ffbbc6f703d66541481bab5d8cbb2e3
tree5bc73aa60ecc49695fd9bf8bab550ac1e75657be
parent44f2ee101f244342ec7e4cd81bb21d9a0c23267b
parent7c5e3e1f8e4671b383865df0150b549e2445d170
signaturelock-open Commit is signed but in an unrecognized format.

Merge branch 'raulgrell-BitByteOffsetOfs'

8 files changed, 233 insertions(+), 72 deletions(-)

doc/langref.html.in+28-6
......@@ -1947,6 +1947,15 @@ test "linked list" {
19471947 assert(list2.first.?.data == 1234);
19481948}
19491949 {#code_end#}
1950 {#header_open|packed struct#}
1951 <p>{#syntax#}packed{#endsyntax#} structs have guaranteed in-memory layout.</p>
1952 <p>TODO bit fields</p>
1953 <p>TODO alignment</p>
1954 <p>TODO endianness</p>
1955 <p>TODO @bitOffsetOf and @byteOffsetOf</p>
1956 <p>TODO mention how volatile loads and stores of bit packed fields could be more efficient when
1957 done by hand instead of with packed struct</p>
1958 {#header_close#}
19501959 {#header_open|struct Naming#}
19511960 <p>Since all structs are anonymous, Zig infers the type name based on a few rules.</p>
19521961 <ul>
......@@ -5135,6 +5144,18 @@ fn seq(c: u8) void {
51355144 Works at compile-time if {#syntax#}value{#endsyntax#} is known at compile time. It's a compile error to bitcast a struct to a scalar type of the same size since structs have undefined layout. However if the struct is packed then it works.
51365145 </p>
51375146 {#header_close#}
5147 {#header_open|@bitOffsetOf#}
5148 <pre>{#syntax#}@bitOffsetOf(comptime T: type, comptime field_name: [] const u8) comptime_int{#endsyntax#}</pre>
5149 <p>
5150 Returns the bit offset of a field relative to its containing struct.
5151 </p>
5152 <p>
5153 For non {#link|packed structs|packed struct#}, this will always be divisible by {#syntax#}8{#endsyntax#}.
5154 For packed structs, non-byte-aligned fields will share a byte offset, but they will have different
5155 bit offsets.
5156 </p>
5157 {#see_also|@byteOffsetOf#}
5158 {#header_close#}
51385159 {#header_open|@breakpoint#}
51395160 <pre>{#syntax#}@breakpoint(){#endsyntax#}</pre>
51405161 <p>
......@@ -5145,6 +5166,13 @@ fn seq(c: u8) void {
51455166 This function is only valid within function scope.
51465167 </p>
51475168
5169 {#header_close#}
5170 {#header_open|@byteOffsetOf#}
5171 <pre>{#syntax#}@byteOffsetOf(comptime T: type, comptime field_name: [] const u8) comptime_int{#endsyntax#}</pre>
5172 <p>
5173 Returns the byte offset of a field relative to its containing struct.
5174 </p>
5175 {#see_also|@bitOffsetOf#}
51485176 {#header_close#}
51495177 {#header_open|@alignCast#}
51505178 <pre>{#syntax#}@alignCast(comptime alignment: u29, ptr: var) var{#endsyntax#}</pre>
......@@ -5868,12 +5896,6 @@ fn add(a: i32, b: i32) i32 {
58685896 </p>
58695897 {#see_also|@inlineCall#}
58705898 {#header_close#}
5871 {#header_open|@offsetOf#}
5872 <pre>{#syntax#}@offsetOf(comptime T: type, comptime field_name: [] const u8) comptime_int{#endsyntax#}</pre>
5873 <p>
5874 This function returns the byte offset of a field relative to its containing struct.
5875 </p>
5876 {#header_close#}
58775899 {#header_open|@OpaqueType#}
58785900 <pre>{#syntax#}@OpaqueType() type{#endsyntax#}</pre>
58795901 <p>
src/all_types.hpp+12-3
......@@ -1409,7 +1409,8 @@ enum BuiltinFnId {
14091409 BuiltinFnIdTagName,
14101410 BuiltinFnIdTagType,
14111411 BuiltinFnIdFieldParentPtr,
1412 BuiltinFnIdOffsetOf,
1412 BuiltinFnIdByteOffsetOf,
1413 BuiltinFnIdBitOffsetOf,
14131414 BuiltinFnIdInlineCall,
14141415 BuiltinFnIdNoInlineCall,
14151416 BuiltinFnIdNewStackCall,
......@@ -2134,7 +2135,8 @@ enum IrInstructionId {
21342135 IrInstructionIdTagName,
21352136 IrInstructionIdTagType,
21362137 IrInstructionIdFieldParentPtr,
2137 IrInstructionIdOffsetOf,
2138 IrInstructionIdByteOffsetOf,
2139 IrInstructionIdBitOffsetOf,
21382140 IrInstructionIdTypeInfo,
21392141 IrInstructionIdTypeId,
21402142 IrInstructionIdSetEvalBranchQuota,
......@@ -3037,7 +3039,14 @@ struct IrInstructionFieldParentPtr {
30373039 TypeStructField *field;
30383040};
30393041
3040struct IrInstructionOffsetOf {
3042struct IrInstructionByteOffsetOf {
3043 IrInstruction base;
3044
3045 IrInstruction *type_value;
3046 IrInstruction *field_name;
3047};
3048
3049struct IrInstructionBitOffsetOf {
30413050 IrInstruction base;
30423051
30433052 IrInstruction *type_value;
src/codegen.cpp+4-2
......@@ -5098,7 +5098,8 @@ static LLVMValueRef ir_render_instruction(CodeGen *g, IrExecutable *executable,
50985098 case IrInstructionIdTypeName:
50995099 case IrInstructionIdDeclRef:
51005100 case IrInstructionIdSwitchVar:
5101 case IrInstructionIdOffsetOf:
5101 case IrInstructionIdByteOffsetOf:
5102 case IrInstructionIdBitOffsetOf:
51025103 case IrInstructionIdTypeInfo:
51035104 case IrInstructionIdTypeId:
51045105 case IrInstructionIdSetEvalBranchQuota:
......@@ -6671,7 +6672,8 @@ static void define_builtin_fns(CodeGen *g) {
66716672 create_builtin_fn(g, BuiltinFnIdTagName, "tagName", 1);
66726673 create_builtin_fn(g, BuiltinFnIdTagType, "TagType", 1);
66736674 create_builtin_fn(g, BuiltinFnIdFieldParentPtr, "fieldParentPtr", 3);
6674 create_builtin_fn(g, BuiltinFnIdOffsetOf, "offsetOf", 2);
6675 create_builtin_fn(g, BuiltinFnIdByteOffsetOf, "byteOffsetOf", 2);
6676 create_builtin_fn(g, BuiltinFnIdBitOffsetOf, "bitOffsetOf", 2);
66756677 create_builtin_fn(g, BuiltinFnIdDivExact, "divExact", 2);
66766678 create_builtin_fn(g, BuiltinFnIdDivTrunc, "divTrunc", 2);
66776679 create_builtin_fn(g, BuiltinFnIdDivFloor, "divFloor", 2);
src/ir.cpp+94-24
......@@ -720,8 +720,12 @@ static constexpr IrInstructionId ir_instruction_id(IrInstructionFieldParentPtr *
720720 return IrInstructionIdFieldParentPtr;
721721}
722722
723static constexpr IrInstructionId ir_instruction_id(IrInstructionOffsetOf *) {
724 return IrInstructionIdOffsetOf;
723static constexpr IrInstructionId ir_instruction_id(IrInstructionByteOffsetOf *) {
724 return IrInstructionIdByteOffsetOf;
725}
726
727static constexpr IrInstructionId ir_instruction_id(IrInstructionBitOffsetOf *) {
728 return IrInstructionIdBitOffsetOf;
725729}
726730
727731static constexpr IrInstructionId ir_instruction_id(IrInstructionTypeInfo *) {
......@@ -2628,10 +2632,23 @@ static IrInstruction *ir_build_field_parent_ptr(IrBuilder *irb, Scope *scope, As
26282632 return &instruction->base;
26292633}
26302634
2631static IrInstruction *ir_build_offset_of(IrBuilder *irb, Scope *scope, AstNode *source_node,
2635static IrInstruction *ir_build_byte_offset_of(IrBuilder *irb, Scope *scope, AstNode *source_node,
26322636 IrInstruction *type_value, IrInstruction *field_name)
26332637{
2634 IrInstructionOffsetOf *instruction = ir_build_instruction<IrInstructionOffsetOf>(irb, scope, source_node);
2638 IrInstructionByteOffsetOf *instruction = ir_build_instruction<IrInstructionByteOffsetOf>(irb, scope, source_node);
2639 instruction->type_value = type_value;
2640 instruction->field_name = field_name;
2641
2642 ir_ref_instruction(type_value, irb->current_basic_block);
2643 ir_ref_instruction(field_name, irb->current_basic_block);
2644
2645 return &instruction->base;
2646}
2647
2648static IrInstruction *ir_build_bit_offset_of(IrBuilder *irb, Scope *scope, AstNode *source_node,
2649 IrInstruction *type_value, IrInstruction *field_name)
2650{
2651 IrInstructionBitOffsetOf *instruction = ir_build_instruction<IrInstructionBitOffsetOf>(irb, scope, source_node);
26352652 instruction->type_value = type_value;
26362653 instruction->field_name = field_name;
26372654
......@@ -4688,7 +4705,7 @@ static IrInstruction *ir_gen_builtin_fn_call(IrBuilder *irb, Scope *scope, AstNo
46884705 IrInstruction *field_parent_ptr = ir_build_field_parent_ptr(irb, scope, node, arg0_value, arg1_value, arg2_value, nullptr);
46894706 return ir_lval_wrap(irb, scope, field_parent_ptr, lval);
46904707 }
4691 case BuiltinFnIdOffsetOf:
4708 case BuiltinFnIdByteOffsetOf:
46924709 {
46934710 AstNode *arg0_node = node->data.fn_call_expr.params.at(0);
46944711 IrInstruction *arg0_value = ir_gen_node(irb, arg0_node, scope);
......@@ -4700,7 +4717,22 @@ static IrInstruction *ir_gen_builtin_fn_call(IrBuilder *irb, Scope *scope, AstNo
47004717 if (arg1_value == irb->codegen->invalid_instruction)
47014718 return arg1_value;
47024719
4703 IrInstruction *offset_of = ir_build_offset_of(irb, scope, node, arg0_value, arg1_value);
4720 IrInstruction *offset_of = ir_build_byte_offset_of(irb, scope, node, arg0_value, arg1_value);
4721 return ir_lval_wrap(irb, scope, offset_of, lval);
4722 }
4723 case BuiltinFnIdBitOffsetOf:
4724 {
4725 AstNode *arg0_node = node->data.fn_call_expr.params.at(0);
4726 IrInstruction *arg0_value = ir_gen_node(irb, arg0_node, scope);
4727 if (arg0_value == irb->codegen->invalid_instruction)
4728 return arg0_value;
4729
4730 AstNode *arg1_node = node->data.fn_call_expr.params.at(1);
4731 IrInstruction *arg1_value = ir_gen_node(irb, arg1_node, scope);
4732 if (arg1_value == irb->codegen->invalid_instruction)
4733 return arg1_value;
4734
4735 IrInstruction *offset_of = ir_build_bit_offset_of(irb, scope, node, arg0_value, arg1_value);
47044736 return ir_lval_wrap(irb, scope, offset_of, lval);
47054737 }
47064738 case BuiltinFnIdInlineCall:
......@@ -17010,49 +17042,84 @@ static ZigType *ir_analyze_instruction_field_parent_ptr(IrAnalyze *ira,
1701017042 return result_type;
1701117043}
1701217044
17013static ZigType *ir_analyze_instruction_offset_of(IrAnalyze *ira,
17014 IrInstructionOffsetOf *instruction)
17045static TypeStructField *validate_byte_offset(IrAnalyze *ira,
17046 IrInstruction *type_value,
17047 IrInstruction *field_name_value,
17048 size_t *byte_offset)
1701517049{
17016 Error err;
17017 IrInstruction *type_value = instruction->type_value->other;
1701817050 ZigType *container_type = ir_resolve_type(ira, type_value);
1701917051 if (type_is_invalid(container_type))
17020 return ira->codegen->builtin_types.entry_invalid;
17052 return nullptr;
1702117053
17054 Error err;
1702217055 if ((err = ensure_complete_type(ira->codegen, container_type)))
17023 return ira->codegen->builtin_types.entry_invalid;
17056 return nullptr;
1702417057
17025 IrInstruction *field_name_value = instruction->field_name->other;
1702617058 Buf *field_name = ir_resolve_str(ira, field_name_value);
1702717059 if (!field_name)
17028 return ira->codegen->builtin_types.entry_invalid;
17060 return nullptr;
1702917061
1703017062 if (container_type->id != ZigTypeIdStruct) {
1703117063 ir_add_error(ira, type_value,
1703217064 buf_sprintf("expected struct type, found '%s'", buf_ptr(&container_type->name)));
17033 return ira->codegen->builtin_types.entry_invalid;
17065 return nullptr;
1703417066 }
1703517067
1703617068 TypeStructField *field = find_struct_type_field(container_type, field_name);
1703717069 if (field == nullptr) {
1703817070 ir_add_error(ira, field_name_value,
1703917071 buf_sprintf("struct '%s' has no field '%s'",
17040 buf_ptr(&container_type->name), buf_ptr(field_name)));
17041 return ira->codegen->builtin_types.entry_invalid;
17072 buf_ptr(&container_type->name), buf_ptr(field_name)));
17073 return nullptr;
1704217074 }
1704317075
1704417076 if (!type_has_bits(field->type_entry)) {
1704517077 ir_add_error(ira, field_name_value,
17046 buf_sprintf("zero-bit field '%s' in struct '%s' has no offset",
17047 buf_ptr(field_name), buf_ptr(&container_type->name)));
17048 return ira->codegen->builtin_types.entry_invalid;
17078 buf_sprintf("zero-bit field '%s' in struct '%s' has no offset",
17079 buf_ptr(field_name), buf_ptr(&container_type->name)));
17080 return nullptr;
1704917081 }
17050 size_t byte_offset = LLVMOffsetOfElement(ira->codegen->target_data_ref, container_type->type_ref, field->gen_index);
17082
17083 *byte_offset = LLVMOffsetOfElement(ira->codegen->target_data_ref, container_type->type_ref, field->gen_index);
17084 return field;
17085}
17086
17087static ZigType *ir_analyze_instruction_byte_offset_of(IrAnalyze *ira,
17088 IrInstructionByteOffsetOf *instruction)
17089{
17090 IrInstruction *type_value = instruction->type_value->other;
17091 if (type_is_invalid(type_value->value.type))
17092 return ira->codegen->builtin_types.entry_invalid;
17093
17094 IrInstruction *field_name_value = instruction->field_name->other;
17095 size_t byte_offset = 0;
17096 if (!validate_byte_offset(ira, type_value, field_name_value, &byte_offset))
17097 return ira->codegen->builtin_types.entry_invalid;
17098
17099
1705117100 ConstExprValue *out_val = ir_build_const_from(ira, &instruction->base);
1705217101 bigint_init_unsigned(&out_val->data.x_bigint, byte_offset);
1705317102 return ira->codegen->builtin_types.entry_num_lit_int;
1705417103}
1705517104
17105static ZigType *ir_analyze_instruction_bit_offset_of(IrAnalyze *ira,
17106 IrInstructionBitOffsetOf *instruction)
17107{
17108 IrInstruction *type_value = instruction->type_value->other;
17109 if (type_is_invalid(type_value->value.type))
17110 return ira->codegen->builtin_types.entry_invalid;
17111 IrInstruction *field_name_value = instruction->field_name->other;
17112 size_t byte_offset = 0;
17113 TypeStructField *field = nullptr;
17114 if (!(field = validate_byte_offset(ira, type_value, field_name_value, &byte_offset)))
17115 return ira->codegen->builtin_types.entry_invalid;
17116
17117 size_t bit_offset = byte_offset * 8 + field->packed_bits_offset;
17118 ConstExprValue *out_val = ir_build_const_from(ira, &instruction->base);
17119 bigint_init_unsigned(&out_val->data.x_bigint, bit_offset);
17120 return ira->codegen->builtin_types.entry_num_lit_int;
17121}
17122
1705617123static void ensure_field_index(ZigType *type, const char *field_name, size_t index)
1705717124{
1705817125 Buf *field_name_buf;
......@@ -21550,8 +21617,10 @@ static ZigType *ir_analyze_instruction_nocast(IrAnalyze *ira, IrInstruction *ins
2155021617 return ir_analyze_instruction_enum_tag_name(ira, (IrInstructionTagName *)instruction);
2155121618 case IrInstructionIdFieldParentPtr:
2155221619 return ir_analyze_instruction_field_parent_ptr(ira, (IrInstructionFieldParentPtr *)instruction);
21553 case IrInstructionIdOffsetOf:
21554 return ir_analyze_instruction_offset_of(ira, (IrInstructionOffsetOf *)instruction);
21620 case IrInstructionIdByteOffsetOf:
21621 return ir_analyze_instruction_byte_offset_of(ira, (IrInstructionByteOffsetOf *)instruction);
21622 case IrInstructionIdBitOffsetOf:
21623 return ir_analyze_instruction_bit_offset_of(ira, (IrInstructionBitOffsetOf *)instruction);
2155521624 case IrInstructionIdTypeInfo:
2155621625 return ir_analyze_instruction_type_info(ira, (IrInstructionTypeInfo *) instruction);
2155721626 case IrInstructionIdTypeId:
......@@ -21835,7 +21904,8 @@ bool ir_has_side_effects(IrInstruction *instruction) {
2183521904 case IrInstructionIdTypeName:
2183621905 case IrInstructionIdTagName:
2183721906 case IrInstructionIdFieldParentPtr:
21838 case IrInstructionIdOffsetOf:
21907 case IrInstructionIdByteOffsetOf:
21908 case IrInstructionIdBitOffsetOf:
2183921909 case IrInstructionIdTypeInfo:
2184021910 case IrInstructionIdTypeId:
2184121911 case IrInstructionIdAlignCast:
src/ir_print.cpp+15-4
......@@ -1041,8 +1041,16 @@ static void ir_print_field_parent_ptr(IrPrint *irp, IrInstructionFieldParentPtr
10411041 fprintf(irp->f, ")");
10421042}
10431043
1044static void ir_print_offset_of(IrPrint *irp, IrInstructionOffsetOf *instruction) {
1045 fprintf(irp->f, "@offset_of(");
1044static void ir_print_byte_offset_of(IrPrint *irp, IrInstructionByteOffsetOf *instruction) {
1045 fprintf(irp->f, "@byte_offset_of(");
1046 ir_print_other_instruction(irp, instruction->type_value);
1047 fprintf(irp->f, ",");
1048 ir_print_other_instruction(irp, instruction->field_name);
1049 fprintf(irp->f, ")");
1050}
1051
1052static void ir_print_bit_offset_of(IrPrint *irp, IrInstructionBitOffsetOf *instruction) {
1053 fprintf(irp->f, "@bit_offset_of(");
10461054 ir_print_other_instruction(irp, instruction->type_value);
10471055 fprintf(irp->f, ",");
10481056 ir_print_other_instruction(irp, instruction->field_name);
......@@ -1649,8 +1657,11 @@ static void ir_print_instruction(IrPrint *irp, IrInstruction *instruction) {
16491657 case IrInstructionIdFieldParentPtr:
16501658 ir_print_field_parent_ptr(irp, (IrInstructionFieldParentPtr *)instruction);
16511659 break;
1652 case IrInstructionIdOffsetOf:
1653 ir_print_offset_of(irp, (IrInstructionOffsetOf *)instruction);
1660 case IrInstructionIdByteOffsetOf:
1661 ir_print_byte_offset_of(irp, (IrInstructionByteOffsetOf *)instruction);
1662 break;
1663 case IrInstructionIdBitOffsetOf:
1664 ir_print_bit_offset_of(irp, (IrInstructionBitOffsetOf *)instruction);
16541665 break;
16551666 case IrInstructionIdTypeInfo:
16561667 ir_print_type_info(irp, (IrInstructionTypeInfo *)instruction);
std/c/darwin.zig+13-13
......@@ -158,12 +158,12 @@ const std = @import("../index.zig");
158158const assert = std.debug.assert;
159159
160160comptime {
161 assert(@offsetOf(Kevent, "ident") == 0);
162 assert(@offsetOf(Kevent, "filter") == 8);
163 assert(@offsetOf(Kevent, "flags") == 10);
164 assert(@offsetOf(Kevent, "fflags") == 12);
165 assert(@offsetOf(Kevent, "data") == 16);
166 assert(@offsetOf(Kevent, "udata") == 24);
161 assert(@byteOffsetOf(Kevent, "ident") == 0);
162 assert(@byteOffsetOf(Kevent, "filter") == 8);
163 assert(@byteOffsetOf(Kevent, "flags") == 10);
164 assert(@byteOffsetOf(Kevent, "fflags") == 12);
165 assert(@byteOffsetOf(Kevent, "data") == 16);
166 assert(@byteOffsetOf(Kevent, "udata") == 24);
167167}
168168
169169pub const kevent64_s = extern struct {
......@@ -180,11 +180,11 @@ pub const kevent64_s = extern struct {
180180// to make sure the struct is laid out the same. These values were
181181// produced from C code using the offsetof macro.
182182comptime {
183 assert(@offsetOf(kevent64_s, "ident") == 0);
184 assert(@offsetOf(kevent64_s, "filter") == 8);
185 assert(@offsetOf(kevent64_s, "flags") == 10);
186 assert(@offsetOf(kevent64_s, "fflags") == 12);
187 assert(@offsetOf(kevent64_s, "data") == 16);
188 assert(@offsetOf(kevent64_s, "udata") == 24);
189 assert(@offsetOf(kevent64_s, "ext") == 32);
183 assert(@byteOffsetOf(kevent64_s, "ident") == 0);
184 assert(@byteOffsetOf(kevent64_s, "filter") == 8);
185 assert(@byteOffsetOf(kevent64_s, "flags") == 10);
186 assert(@byteOffsetOf(kevent64_s, "fflags") == 12);
187 assert(@byteOffsetOf(kevent64_s, "data") == 16);
188 assert(@byteOffsetOf(kevent64_s, "udata") == 24);
189 assert(@byteOffsetOf(kevent64_s, "ext") == 32);
190190}
test/cases/sizeof_and_typeof.zig+46-11
......@@ -1,6 +1,7 @@
1const builtin = @import("builtin");
12const assert = @import("std").debug.assert;
23
3test "sizeofAndTypeOf" {
4test "@sizeOf and @typeOf" {
45 const y: @typeOf(x) = 120;
56 assert(@sizeOf(@typeOf(y)) == 2);
67}
......@@ -11,24 +12,58 @@ const A = struct {
1112 a: u8,
1213 b: u32,
1314 c: u8,
15 d: u3,
16 e: u5,
17 f: u16,
18 g: u16,
1419};
1520
1621const P = packed struct {
1722 a: u8,
1823 b: u32,
1924 c: u8,
25 d: u3,
26 e: u5,
27 f: u16,
28 g: u16,
2029};
2130
22test "offsetOf" {
31test "@byteOffsetOf" {
2332 // Packed structs have fixed memory layout
24 const p: P = undefined;
25 assert(@offsetOf(P, "a") == 0);
26 assert(@offsetOf(@typeOf(p), "b") == 1);
27 assert(@offsetOf(@typeOf(p), "c") == 5);
33 assert(@byteOffsetOf(P, "a") == 0);
34 assert(@byteOffsetOf(P, "b") == 1);
35 assert(@byteOffsetOf(P, "c") == 5);
36 assert(@byteOffsetOf(P, "d") == 6);
37 assert(@byteOffsetOf(P, "e") == 6);
38 assert(@byteOffsetOf(P, "f") == 7);
39 assert(@byteOffsetOf(P, "g") == 9);
2840
29 // Non-packed struct fields can be moved/padded
30 const a: A = undefined;
31 assert(@ptrToInt(&a.a) - @ptrToInt(&a) == @offsetOf(A, "a"));
32 assert(@ptrToInt(&a.b) - @ptrToInt(&a) == @offsetOf(@typeOf(a), "b"));
33 assert(@ptrToInt(&a.c) - @ptrToInt(&a) == @offsetOf(@typeOf(a), "c"));
41 // Normal struct fields can be moved/padded
42 var a: A = undefined;
43 assert(@ptrToInt(&a.a) - @ptrToInt(&a) == @byteOffsetOf(A, "a"));
44 assert(@ptrToInt(&a.b) - @ptrToInt(&a) == @byteOffsetOf(A, "b"));
45 assert(@ptrToInt(&a.c) - @ptrToInt(&a) == @byteOffsetOf(A, "c"));
46 assert(@ptrToInt(&a.d) - @ptrToInt(&a) == @byteOffsetOf(A, "d"));
47 assert(@ptrToInt(&a.e) - @ptrToInt(&a) == @byteOffsetOf(A, "e"));
48 assert(@ptrToInt(&a.f) - @ptrToInt(&a) == @byteOffsetOf(A, "f"));
49 assert(@ptrToInt(&a.g) - @ptrToInt(&a) == @byteOffsetOf(A, "g"));
50}
51
52test "@bitOffsetOf" {
53 // Packed structs have fixed memory layout
54 assert(@bitOffsetOf(P, "a") == 0);
55 assert(@bitOffsetOf(P, "b") == 8);
56 assert(@bitOffsetOf(P, "c") == 40);
57 assert(@bitOffsetOf(P, "d") == 48);
58 assert(@bitOffsetOf(P, "e") == 51);
59 assert(@bitOffsetOf(P, "f") == 56);
60 assert(@bitOffsetOf(P, "g") == 72);
61
62 assert(@byteOffsetOf(A, "a") * 8 == @bitOffsetOf(A, "a"));
63 assert(@byteOffsetOf(A, "b") * 8 == @bitOffsetOf(A, "b"));
64 assert(@byteOffsetOf(A, "c") * 8 == @bitOffsetOf(A, "c"));
65 assert(@byteOffsetOf(A, "d") * 8 == @bitOffsetOf(A, "d"));
66 assert(@byteOffsetOf(A, "e") * 8 == @bitOffsetOf(A, "e"));
67 assert(@byteOffsetOf(A, "f") * 8 == @bitOffsetOf(A, "f"));
68 assert(@byteOffsetOf(A, "g") * 8 == @bitOffsetOf(A, "g"));
3469}
test/compile_errors.zig+21-9
......@@ -3763,25 +3763,25 @@ pub fn addCases(cases: *tests.CompileErrorContext) void {
37633763 );
37643764
37653765 cases.add(
3766 "@offsetOf - non struct",
3766 "@byteOffsetOf - non struct",
37673767 \\const Foo = i32;
37683768 \\export fn foo() usize {
3769 \\ return @offsetOf(Foo, "a",);
3769 \\ return @byteOffsetOf(Foo, "a",);
37703770 \\}
37713771 ,
3772 ".tmp_source.zig:3:22: error: expected struct type, found 'i32'",
3772 ".tmp_source.zig:3:26: error: expected struct type, found 'i32'",
37733773 );
37743774
37753775 cases.add(
3776 "@offsetOf - bad field name",
3776 "@byteOffsetOf - bad field name",
37773777 \\const Foo = struct {
37783778 \\ derp: i32,
37793779 \\};
37803780 \\export fn foo() usize {
3781 \\ return @offsetOf(Foo, "a",);
3781 \\ return @byteOffsetOf(Foo, "a",);
37823782 \\}
37833783 ,
3784 ".tmp_source.zig:5:27: error: struct 'Foo' has no field 'a'",
3784 ".tmp_source.zig:5:31: error: struct 'Foo' has no field 'a'",
37853785 );
37863786
37873787 cases.addExe(
......@@ -5084,15 +5084,27 @@ pub fn addCases(cases: *tests.CompileErrorContext) void {
50845084 );
50855085
50865086 cases.add(
5087 "taking offset of void field in struct",
5087 "taking byte offset of void field in struct",
50885088 \\const Empty = struct {
50895089 \\ val: void,
50905090 \\};
50915091 \\export fn foo() void {
5092 \\ const fieldOffset = @offsetOf(Empty, "val",);
5092 \\ const fieldOffset = @byteOffsetOf(Empty, "val",);
50935093 \\}
50945094 ,
5095 ".tmp_source.zig:5:42: error: zero-bit field 'val' in struct 'Empty' has no offset",
5095 ".tmp_source.zig:5:46: error: zero-bit field 'val' in struct 'Empty' has no offset",
5096 );
5097
5098 cases.add(
5099 "taking bit offset of void field in struct",
5100 \\const Empty = struct {
5101 \\ val: void,
5102 \\};
5103 \\export fn foo() void {
5104 \\ const fieldOffset = @bitOffsetOf(Empty, "val",);
5105 \\}
5106 ,
5107 ".tmp_source.zig:5:45: error: zero-bit field 'val' in struct 'Empty' has no offset",
50965108 );
50975109
50985110 cases.add(