Source
pub fn declIterator(zir: Zir, decl_inst: Zir.Inst.Index) DeclIterator {
const inst = zir.instructions.get(@intFromEnum(decl_inst));
assert(inst.tag == .extended);
const extended = inst.data.extended;
switch (extended.opcode) {
.struct_decl => {
const small: Inst.StructDecl.Small = @bitCast(extended.small);
var extra_index: u32 = @intCast(extended.operand + @typeInfo(Inst.StructDecl).@"struct".fields.len);
const captures_len = if (small.has_captures_len) captures_len: {
const captures_len = zir.extra[extra_index];
extra_index += 1;
break :captures_len captures_len;
} else 0;
extra_index += @intFromBool(small.has_fields_len);
const decls_len = if (small.has_decls_len) decls_len: {
const decls_len = zir.extra[extra_index];
extra_index += 1;
break :decls_len decls_len;
} else 0;
extra_index += captures_len * 2;
if (small.has_backing_int) {
const backing_int_body_len = zir.extra[extra_index];
extra_index += 1; // backing_int_body_len
if (backing_int_body_len == 0) {
extra_index += 1; // backing_int_ref
} else {
extra_index += backing_int_body_len; // backing_int_body_inst
}
}
return .{
.extra_index = extra_index,
.decls_remaining = decls_len,
.zir = zir,
};
},
.enum_decl => {
const small: Inst.EnumDecl.Small = @bitCast(extended.small);
var extra_index: u32 = @intCast(extended.operand + @typeInfo(Inst.EnumDecl).@"struct".fields.len);
extra_index += @intFromBool(small.has_tag_type);
const captures_len = if (small.has_captures_len) captures_len: {
const captures_len = zir.extra[extra_index];
extra_index += 1;
break :captures_len captures_len;
} else 0;
extra_index += @intFromBool(small.has_body_len);
extra_index += @intFromBool(small.has_fields_len);
const decls_len = if (small.has_decls_len) decls_len: {
const decls_len = zir.extra[extra_index];
extra_index += 1;
break :decls_len decls_len;
} else 0;
extra_index += captures_len * 2;
return .{
.extra_index = extra_index,
.decls_remaining = decls_len,
.zir = zir,
};
},
.union_decl => {
const small: Inst.UnionDecl.Small = @bitCast(extended.small);
var extra_index: u32 = @intCast(extended.operand + @typeInfo(Inst.UnionDecl).@"struct".fields.len);
extra_index += @intFromBool(small.has_tag_type);
const captures_len = if (small.has_captures_len) captures_len: {
const captures_len = zir.extra[extra_index];
extra_index += 1;
break :captures_len captures_len;
} else 0;
extra_index += @intFromBool(small.has_body_len);
extra_index += @intFromBool(small.has_fields_len);
const decls_len = if (small.has_decls_len) decls_len: {
const decls_len = zir.extra[extra_index];
extra_index += 1;
break :decls_len decls_len;
} else 0;
extra_index += captures_len * 2;
return .{
.extra_index = extra_index,
.decls_remaining = decls_len,
.zir = zir,
};
},
.opaque_decl => {
const small: Inst.OpaqueDecl.Small = @bitCast(extended.small);
var extra_index: u32 = @intCast(extended.operand + @typeInfo(Inst.OpaqueDecl).@"struct".fields.len);
const decls_len = if (small.has_decls_len) decls_len: {
const decls_len = zir.extra[extra_index];
extra_index += 1;
break :decls_len decls_len;
} else 0;
const captures_len = if (small.has_captures_len) captures_len: {
const captures_len = zir.extra[extra_index];
extra_index += 1;
break :captures_len captures_len;
} else 0;
extra_index += captures_len * 2;
return .{
.extra_index = extra_index,
.decls_remaining = decls_len,
.zir = zir,
};
},
else => unreachable,
}
}