rustc_codegen_llvm/debuginfo/metadata/enums/native.rs
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435
use std::borrow::Cow;
use libc::c_uint;
use rustc_abi::{Size, TagEncoding, VariantIdx, Variants};
use rustc_codegen_ssa::debuginfo::type_names::compute_debuginfo_type_name;
use rustc_codegen_ssa::debuginfo::{tag_base_type, wants_c_like_enum_debuginfo};
use rustc_codegen_ssa::traits::ConstCodegenMethods;
use rustc_middle::bug;
use rustc_middle::ty::layout::{LayoutOf, TyAndLayout};
use rustc_middle::ty::{self};
use smallvec::smallvec;
use crate::common::{AsCCharPtr, CodegenCx};
use crate::debuginfo::metadata::type_map::{self, Stub, StubInfo, UniqueTypeId};
use crate::debuginfo::metadata::{
DINodeCreationResult, NO_GENERICS, SmallVec, UNKNOWN_LINE_NUMBER, file_metadata,
size_and_align_of, type_di_node, unknown_file_metadata, visibility_di_flags,
};
use crate::debuginfo::utils::{DIB, create_DIArray, get_namespace_for_item};
use crate::llvm::debuginfo::{DIFile, DIFlags, DIType};
use crate::llvm::{self};
/// Build the debuginfo node for an enum type. The listing below shows how such a
/// type looks like at the LLVM IR/DWARF level. It is a `DW_TAG_structure_type`
/// with a single `DW_TAG_variant_part` that in turn contains a `DW_TAG_variant`
/// for each variant of the enum. The variant-part also contains a single member
/// describing the discriminant, and a nested struct type for each of the variants.
///
/// ```txt
/// ---> DW_TAG_structure_type (top-level type for enum)
/// DW_TAG_variant_part (variant part)
/// DW_AT_discr (reference to discriminant DW_TAG_member)
/// DW_TAG_member (discriminant member)
/// DW_TAG_variant (variant 1)
/// DW_TAG_variant (variant 2)
/// DW_TAG_variant (variant 3)
/// DW_TAG_structure_type (type of variant 1)
/// DW_TAG_structure_type (type of variant 2)
/// DW_TAG_structure_type (type of variant 3)
/// ```
pub(super) fn build_enum_type_di_node<'ll, 'tcx>(
cx: &CodegenCx<'ll, 'tcx>,
unique_type_id: UniqueTypeId<'tcx>,
) -> DINodeCreationResult<'ll> {
let enum_type = unique_type_id.expect_ty();
let &ty::Adt(enum_adt_def, _) = enum_type.kind() else {
bug!("build_enum_type_di_node() called with non-enum type: `{:?}`", enum_type)
};
let containing_scope = get_namespace_for_item(cx, enum_adt_def.did());
let enum_type_and_layout = cx.layout_of(enum_type);
let enum_type_name = compute_debuginfo_type_name(cx.tcx, enum_type, false);
let visibility_flags = visibility_di_flags(cx, enum_adt_def.did(), enum_adt_def.did());
assert!(!wants_c_like_enum_debuginfo(cx.tcx, enum_type_and_layout));
type_map::build_type_with_children(
cx,
type_map::stub(
cx,
Stub::Struct,
unique_type_id,
&enum_type_name,
size_and_align_of(enum_type_and_layout),
Some(containing_scope),
visibility_flags,
),
|cx, enum_type_di_node| {
// Build the struct type for each variant. These will be referenced by the
// DW_TAG_variant DIEs inside of the DW_TAG_variant_part DIE.
// We also called the names for the corresponding DW_TAG_variant DIEs here.
let variant_member_infos: SmallVec<_> = enum_adt_def
.variant_range()
.map(|variant_index| VariantMemberInfo {
variant_index,
variant_name: Cow::from(enum_adt_def.variant(variant_index).name.as_str()),
variant_struct_type_di_node: super::build_enum_variant_struct_type_di_node(
cx,
enum_type_and_layout,
enum_type_di_node,
variant_index,
enum_adt_def.variant(variant_index),
enum_type_and_layout.for_variant(cx, variant_index),
visibility_flags,
),
source_info: None,
})
.collect();
smallvec![build_enum_variant_part_di_node(
cx,
enum_type_and_layout,
enum_type_di_node,
&variant_member_infos[..],
)]
},
// We don't seem to be emitting generic args on the enum type, it seems. Rather
// they get attached to the struct type of each variant.
NO_GENERICS,
)
}
/// Build the debuginfo node for a coroutine environment. It looks the same as the debuginfo for
/// an enum. See [build_enum_type_di_node] for more information.
///
/// ```txt
///
/// ---> DW_TAG_structure_type (top-level type for the coroutine)
/// DW_TAG_variant_part (variant part)
/// DW_AT_discr (reference to discriminant DW_TAG_member)
/// DW_TAG_member (discriminant member)
/// DW_TAG_variant (variant 1)
/// DW_TAG_variant (variant 2)
/// DW_TAG_variant (variant 3)
/// DW_TAG_structure_type (type of variant 1)
/// DW_TAG_structure_type (type of variant 2)
/// DW_TAG_structure_type (type of variant 3)
///
/// ```
pub(super) fn build_coroutine_di_node<'ll, 'tcx>(
cx: &CodegenCx<'ll, 'tcx>,
unique_type_id: UniqueTypeId<'tcx>,
) -> DINodeCreationResult<'ll> {
let coroutine_type = unique_type_id.expect_ty();
let &ty::Coroutine(coroutine_def_id, coroutine_args) = coroutine_type.kind() else {
bug!("build_coroutine_di_node() called with non-coroutine type: `{:?}`", coroutine_type)
};
let containing_scope = get_namespace_for_item(cx, coroutine_def_id);
let coroutine_type_and_layout = cx.layout_of(coroutine_type);
assert!(!wants_c_like_enum_debuginfo(cx.tcx, coroutine_type_and_layout));
let coroutine_type_name = compute_debuginfo_type_name(cx.tcx, coroutine_type, false);
type_map::build_type_with_children(
cx,
type_map::stub(
cx,
Stub::Struct,
unique_type_id,
&coroutine_type_name,
size_and_align_of(coroutine_type_and_layout),
Some(containing_scope),
DIFlags::FlagZero,
),
|cx, coroutine_type_di_node| {
let coroutine_layout = cx
.tcx
.coroutine_layout(coroutine_def_id, coroutine_args.as_coroutine().kind_ty())
.unwrap();
let Variants::Multiple { tag_encoding: TagEncoding::Direct, ref variants, .. } =
coroutine_type_and_layout.variants
else {
bug!(
"Encountered coroutine with non-direct-tag layout: {:?}",
coroutine_type_and_layout
)
};
let common_upvar_names =
cx.tcx.closure_saved_names_of_captured_variables(coroutine_def_id);
// Build variant struct types
let variant_struct_type_di_nodes: SmallVec<_> = variants
.indices()
.map(|variant_index| {
// FIXME: This is problematic because just a number is not a valid identifier.
// CoroutineArgs::variant_name(variant_index), would be consistent
// with enums?
let variant_name = format!("{}", variant_index.as_usize()).into();
let span = coroutine_layout.variant_source_info[variant_index].span;
let source_info = if !span.is_dummy() {
let loc = cx.lookup_debug_loc(span.lo());
Some((file_metadata(cx, &loc.file), loc.line))
} else {
None
};
VariantMemberInfo {
variant_index,
variant_name,
variant_struct_type_di_node:
super::build_coroutine_variant_struct_type_di_node(
cx,
variant_index,
coroutine_type_and_layout,
coroutine_type_di_node,
coroutine_layout,
common_upvar_names,
),
source_info,
}
})
.collect();
smallvec![build_enum_variant_part_di_node(
cx,
coroutine_type_and_layout,
coroutine_type_di_node,
&variant_struct_type_di_nodes[..],
)]
},
// We don't seem to be emitting generic args on the coroutine type, it seems. Rather
// they get attached to the struct type of each variant.
NO_GENERICS,
)
}
/// Builds the DW_TAG_variant_part of an enum or coroutine debuginfo node:
///
/// ```txt
/// DW_TAG_structure_type (top-level type for enum)
/// ---> DW_TAG_variant_part (variant part)
/// DW_AT_discr (reference to discriminant DW_TAG_member)
/// DW_TAG_member (discriminant member)
/// DW_TAG_variant (variant 1)
/// DW_TAG_variant (variant 2)
/// DW_TAG_variant (variant 3)
/// DW_TAG_structure_type (type of variant 1)
/// DW_TAG_structure_type (type of variant 2)
/// DW_TAG_structure_type (type of variant 3)
/// ```
fn build_enum_variant_part_di_node<'ll, 'tcx>(
cx: &CodegenCx<'ll, 'tcx>,
enum_type_and_layout: TyAndLayout<'tcx>,
enum_type_di_node: &'ll DIType,
variant_member_infos: &[VariantMemberInfo<'_, 'll>],
) -> &'ll DIType {
let tag_member_di_node =
build_discr_member_di_node(cx, enum_type_and_layout, enum_type_di_node);
let variant_part_unique_type_id =
UniqueTypeId::for_enum_variant_part(cx.tcx, enum_type_and_layout.ty);
let stub = StubInfo::new(
cx,
variant_part_unique_type_id,
|cx, variant_part_unique_type_id_str| unsafe {
let variant_part_name = "";
llvm::LLVMRustDIBuilderCreateVariantPart(
DIB(cx),
enum_type_di_node,
variant_part_name.as_c_char_ptr(),
variant_part_name.len(),
unknown_file_metadata(cx),
UNKNOWN_LINE_NUMBER,
enum_type_and_layout.size.bits(),
enum_type_and_layout.align.abi.bits() as u32,
DIFlags::FlagZero,
tag_member_di_node,
create_DIArray(DIB(cx), &[]),
variant_part_unique_type_id_str.as_c_char_ptr(),
variant_part_unique_type_id_str.len(),
)
},
);
type_map::build_type_with_children(
cx,
stub,
|cx, variant_part_di_node| {
variant_member_infos
.iter()
.map(|variant_member_info| {
build_enum_variant_member_di_node(
cx,
enum_type_and_layout,
variant_part_di_node,
variant_member_info,
)
})
.collect()
},
NO_GENERICS,
)
.di_node
}
/// Builds the DW_TAG_member describing where we can find the tag of an enum.
/// Returns `None` if the enum does not have a tag.
///
/// ```txt
///
/// DW_TAG_structure_type (top-level type for enum)
/// DW_TAG_variant_part (variant part)
/// DW_AT_discr (reference to discriminant DW_TAG_member)
/// ---> DW_TAG_member (discriminant member)
/// DW_TAG_variant (variant 1)
/// DW_TAG_variant (variant 2)
/// DW_TAG_variant (variant 3)
/// DW_TAG_structure_type (type of variant 1)
/// DW_TAG_structure_type (type of variant 2)
/// DW_TAG_structure_type (type of variant 3)
///
/// ```
fn build_discr_member_di_node<'ll, 'tcx>(
cx: &CodegenCx<'ll, 'tcx>,
enum_or_coroutine_type_and_layout: TyAndLayout<'tcx>,
enum_or_coroutine_type_di_node: &'ll DIType,
) -> Option<&'ll DIType> {
let tag_name = match enum_or_coroutine_type_and_layout.ty.kind() {
ty::Coroutine(..) => "__state",
_ => "",
};
// NOTE: This is actually wrong. This will become a member of
// of the DW_TAG_variant_part. But, due to LLVM's API, that
// can only be constructed with this DW_TAG_member already in created.
// In LLVM IR the wrong scope will be listed but when DWARF is
// generated from it, the DW_TAG_member will be a child the
// DW_TAG_variant_part.
let containing_scope = enum_or_coroutine_type_di_node;
match enum_or_coroutine_type_and_layout.layout.variants() {
// A single-variant enum has no discriminant.
&Variants::Single { .. } => None,
&Variants::Multiple { tag_field, .. } => {
let tag_base_type = tag_base_type(cx.tcx, enum_or_coroutine_type_and_layout);
let (size, align) = cx.size_and_align_of(tag_base_type);
unsafe {
Some(llvm::LLVMRustDIBuilderCreateMemberType(
DIB(cx),
containing_scope,
tag_name.as_c_char_ptr(),
tag_name.len(),
unknown_file_metadata(cx),
UNKNOWN_LINE_NUMBER,
size.bits(),
align.bits() as u32,
enum_or_coroutine_type_and_layout.fields.offset(tag_field).bits(),
DIFlags::FlagArtificial,
type_di_node(cx, tag_base_type),
))
}
}
}
}
/// Build the debuginfo node for `DW_TAG_variant`:
///
/// ```txt
/// DW_TAG_structure_type (top-level type for enum)
/// DW_TAG_variant_part (variant part)
/// DW_AT_discr (reference to discriminant DW_TAG_member)
/// DW_TAG_member (discriminant member)
/// ---> DW_TAG_variant (variant 1)
/// ---> DW_TAG_variant (variant 2)
/// ---> DW_TAG_variant (variant 3)
/// DW_TAG_structure_type (type of variant 1)
/// DW_TAG_structure_type (type of variant 2)
/// DW_TAG_structure_type (type of variant 3)
/// ```
///
/// This node looks like:
///
/// ```txt
/// DW_TAG_variant
/// DW_AT_discr_value 0
/// DW_TAG_member
/// DW_AT_name None
/// DW_AT_type <0x000002a1>
/// DW_AT_alignment 0x00000002
/// DW_AT_data_member_location 0
/// ```
///
/// The DW_AT_discr_value is optional, and is omitted if
/// - This is the only variant of a univariant enum (i.e. their is no discriminant)
/// - This is the "untagged" variant of a niche-layout enum
/// (where only the other variants are identified by a single value)
///
/// There is only ever a single member, the type of which is a struct that describes the
/// fields of the variant (excluding the discriminant). The name of the member is the name
/// of the variant as given in the source code. The DW_AT_data_member_location is always
/// zero.
///
/// Note that the LLVM DIBuilder API is a bit unintuitive here. The DW_TAG_variant subtree
/// (including the DW_TAG_member) is built by a single call to
/// `LLVMRustDIBuilderCreateVariantMemberType()`.
fn build_enum_variant_member_di_node<'ll, 'tcx>(
cx: &CodegenCx<'ll, 'tcx>,
enum_type_and_layout: TyAndLayout<'tcx>,
variant_part_di_node: &'ll DIType,
variant_member_info: &VariantMemberInfo<'_, 'll>,
) -> &'ll DIType {
let variant_index = variant_member_info.variant_index;
let discr_value = super::compute_discriminant_value(cx, enum_type_and_layout, variant_index);
let (file_di_node, line_number) = variant_member_info
.source_info
.unwrap_or_else(|| (unknown_file_metadata(cx), UNKNOWN_LINE_NUMBER));
unsafe {
llvm::LLVMRustDIBuilderCreateVariantMemberType(
DIB(cx),
variant_part_di_node,
variant_member_info.variant_name.as_c_char_ptr(),
variant_member_info.variant_name.len(),
file_di_node,
line_number,
enum_type_and_layout.size.bits(),
enum_type_and_layout.align.abi.bits() as u32,
Size::ZERO.bits(),
discr_value.opt_single_val().map(|value| cx.const_u128(value)),
DIFlags::FlagZero,
variant_member_info.variant_struct_type_di_node,
)
}
}
/// Information needed for building a `DW_TAG_variant`:
///
/// ```txt
/// DW_TAG_structure_type (top-level type for enum)
/// DW_TAG_variant_part (variant part)
/// DW_AT_discr (reference to discriminant DW_TAG_member)
/// DW_TAG_member (discriminant member)
/// ---> DW_TAG_variant (variant 1)
/// ---> DW_TAG_variant (variant 2)
/// ---> DW_TAG_variant (variant 3)
/// DW_TAG_structure_type (type of variant 1)
/// DW_TAG_structure_type (type of variant 2)
/// DW_TAG_structure_type (type of variant 3)
/// ```
struct VariantMemberInfo<'a, 'll> {
variant_index: VariantIdx,
variant_name: Cow<'a, str>,
variant_struct_type_di_node: &'ll DIType,
source_info: Option<(&'ll DIFile, c_uint)>,
}