rust/src/librustc_codegen_llvm/debuginfo/metadata.rs

2405 lines
91 KiB
Rust

use self::RecursiveTypeDescription::*;
use self::MemberDescriptionFactory::*;
use self::EnumDiscriminantInfo::*;
use super::utils::{debug_context, DIB, span_start,
get_namespace_for_item, create_DIArray, is_node_local_to_unit};
use super::namespace::mangled_name_of_instance;
use super::type_names::compute_debuginfo_type_name;
use super::CrateDebugContext;
use crate::abi;
use crate::common::CodegenCx;
use crate::llvm;
use crate::llvm::debuginfo::{DIArray, DIType, DIFile, DIScope, DIDescriptor,
DICompositeType, DILexicalBlock, DIFlags, DebugEmissionKind};
use crate::llvm_util;
use crate::value::Value;
use rustc_codegen_ssa::traits::*;
use rustc_index::vec::{Idx, IndexVec};
use rustc_data_structures::stable_hasher::{HashStable, StableHasher};
use rustc::hir::CodegenFnAttrFlags;
use rustc::hir::def::CtorKind;
use rustc::hir::def_id::{DefId, CrateNum, LOCAL_CRATE};
use rustc::ich::NodeIdHashingMode;
use rustc::mir::{self, Field, GeneratorLayout};
use rustc::mir::interpret::truncate;
use rustc_data_structures::fingerprint::Fingerprint;
use rustc::ty::Instance;
use rustc::ty::{self, AdtKind, ParamEnv, Ty, TyCtxt};
use rustc::ty::layout::{self, Align, Integer, IntegerExt, LayoutOf,
PrimitiveExt, Size, TyLayout, VariantIdx};
use rustc::ty::subst::{GenericArgKind, SubstsRef};
use rustc::session::config::{self, DebugInfo};
use rustc::util::nodemap::FxHashMap;
use rustc_fs_util::path_to_c_string;
use rustc_data_structures::small_c_str::SmallCStr;
use rustc_data_structures::const_cstr;
use rustc_target::abi::HasDataLayout;
use syntax::ast;
use syntax::symbol::{Interner, Symbol};
use syntax_pos::{self, Span, FileName};
use rustc::{bug, span_bug};
use log::debug;
use libc::{c_uint, c_longlong};
use std::collections::hash_map::Entry;
use std::ffi::CString;
use std::fmt::{self, Write};
use std::hash::{Hash, Hasher};
use std::iter;
use std::ptr;
use std::path::{Path, PathBuf};
impl PartialEq for llvm::Metadata {
fn eq(&self, other: &Self) -> bool {
ptr::eq(self, other)
}
}
impl Eq for llvm::Metadata {}
impl Hash for llvm::Metadata {
fn hash<H: Hasher>(&self, hasher: &mut H) {
(self as *const Self).hash(hasher);
}
}
impl fmt::Debug for llvm::Metadata {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
(self as *const Self).fmt(f)
}
}
// From DWARF 5.
// See http://www.dwarfstd.org/ShowIssue.php?issue=140129.1.
const DW_LANG_RUST: c_uint = 0x1c;
#[allow(non_upper_case_globals)]
const DW_ATE_boolean: c_uint = 0x02;
#[allow(non_upper_case_globals)]
const DW_ATE_float: c_uint = 0x04;
#[allow(non_upper_case_globals)]
const DW_ATE_signed: c_uint = 0x05;
#[allow(non_upper_case_globals)]
const DW_ATE_unsigned: c_uint = 0x07;
#[allow(non_upper_case_globals)]
const DW_ATE_unsigned_char: c_uint = 0x08;
pub const UNKNOWN_LINE_NUMBER: c_uint = 0;
pub const UNKNOWN_COLUMN_NUMBER: c_uint = 0;
pub const NO_SCOPE_METADATA: Option<&DIScope> = None;
#[derive(Copy, Debug, Hash, Eq, PartialEq, Clone)]
pub struct UniqueTypeId(ast::Name);
/// The `TypeMap` is where the `CrateDebugContext` holds the type metadata nodes
/// created so far. The metadata nodes are indexed by `UniqueTypeId`, and, for
/// faster lookup, also by `Ty`. The `TypeMap` is responsible for creating
/// `UniqueTypeId`s.
#[derive(Default)]
pub struct TypeMap<'ll, 'tcx> {
/// The `UniqueTypeId`s created so far.
unique_id_interner: Interner,
/// A map from `UniqueTypeId` to debuginfo metadata for that type. This is a 1:1 mapping.
unique_id_to_metadata: FxHashMap<UniqueTypeId, &'ll DIType>,
/// A map from types to debuginfo metadata. This is an N:1 mapping.
type_to_metadata: FxHashMap<Ty<'tcx>, &'ll DIType>,
/// A map from types to `UniqueTypeId`. This is an N:1 mapping.
type_to_unique_id: FxHashMap<Ty<'tcx>, UniqueTypeId>
}
impl TypeMap<'ll, 'tcx> {
/// Adds a Ty to metadata mapping to the TypeMap. The method will fail if
/// the mapping already exists.
fn register_type_with_metadata(
&mut self,
type_: Ty<'tcx>,
metadata: &'ll DIType,
) {
if self.type_to_metadata.insert(type_, metadata).is_some() {
bug!("type metadata for `Ty` '{}' is already in the `TypeMap`!", type_);
}
}
/// Removes a `Ty`-to-metadata mapping.
/// This is useful when computing the metadata for a potentially
/// recursive type (e.g., a function pointer of the form:
///
/// fn foo() -> impl Copy { foo }
///
/// This kind of type cannot be properly represented
/// via LLVM debuginfo. As a workaround,
/// we register a temporary Ty to metadata mapping
/// for the function before we compute its actual metadata.
/// If the metadata computation ends up recursing back to the
/// original function, it will use the temporary mapping
/// for the inner self-reference, preventing us from
/// recursing forever.
///
/// This function is used to remove the temporary metadata
/// mapping after we've computed the actual metadata.
fn remove_type(
&mut self,
type_: Ty<'tcx>,
) {
if self.type_to_metadata.remove(type_).is_none() {
bug!("type metadata `Ty` '{}' is not in the `TypeMap`!", type_);
}
}
/// Adds a `UniqueTypeId` to metadata mapping to the `TypeMap`. The method will
/// fail if the mapping already exists.
fn register_unique_id_with_metadata(
&mut self,
unique_type_id: UniqueTypeId,
metadata: &'ll DIType,
) {
if self.unique_id_to_metadata.insert(unique_type_id, metadata).is_some() {
bug!("type metadata for unique ID '{}' is already in the `TypeMap`!",
self.get_unique_type_id_as_string(unique_type_id));
}
}
fn find_metadata_for_type(&self, type_: Ty<'tcx>) -> Option<&'ll DIType> {
self.type_to_metadata.get(&type_).cloned()
}
fn find_metadata_for_unique_id(&self, unique_type_id: UniqueTypeId) -> Option<&'ll DIType> {
self.unique_id_to_metadata.get(&unique_type_id).cloned()
}
/// Gets the string representation of a `UniqueTypeId`. This method will fail if
/// the ID is unknown.
fn get_unique_type_id_as_string(&self, unique_type_id: UniqueTypeId) -> &str {
let UniqueTypeId(interner_key) = unique_type_id;
self.unique_id_interner.get(interner_key)
}
/// Gets the `UniqueTypeId` for the given type. If the `UniqueTypeId` for the given
/// type has been requested before, this is just a table lookup. Otherwise, an
/// ID will be generated and stored for later lookup.
fn get_unique_type_id_of_type<'a>(&mut self, cx: &CodegenCx<'a, 'tcx>,
type_: Ty<'tcx>) -> UniqueTypeId {
// Let's see if we already have something in the cache.
if let Some(unique_type_id) = self.type_to_unique_id.get(&type_).cloned() {
return unique_type_id;
}
// If not, generate one.
// The hasher we are using to generate the UniqueTypeId. We want
// something that provides more than the 64 bits of the DefaultHasher.
let mut hasher = StableHasher::new();
let mut hcx = cx.tcx.create_stable_hashing_context();
let type_ = cx.tcx.erase_regions(&type_);
hcx.while_hashing_spans(false, |hcx| {
hcx.with_node_id_hashing_mode(NodeIdHashingMode::HashDefPath, |hcx| {
type_.hash_stable(hcx, &mut hasher);
});
});
let unique_type_id = hasher.finish::<Fingerprint>().to_hex();
let key = self.unique_id_interner.intern(&unique_type_id);
self.type_to_unique_id.insert(type_, UniqueTypeId(key));
return UniqueTypeId(key);
}
/// Gets the `UniqueTypeId` for an enum variant. Enum variants are not really
/// types of their own, so they need special handling. We still need a
/// `UniqueTypeId` for them, since to debuginfo they *are* real types.
fn get_unique_type_id_of_enum_variant<'a>(&mut self,
cx: &CodegenCx<'a, 'tcx>,
enum_type: Ty<'tcx>,
variant_name: &str)
-> UniqueTypeId {
let enum_type_id = self.get_unique_type_id_of_type(cx, enum_type);
let enum_variant_type_id = format!("{}::{}",
self.get_unique_type_id_as_string(enum_type_id),
variant_name);
let interner_key = self.unique_id_interner.intern(&enum_variant_type_id);
UniqueTypeId(interner_key)
}
/// Gets the unique type ID string for an enum variant part.
/// Variant parts are not types and shouldn't really have their own ID,
/// but it makes `set_members_of_composite_type()` simpler.
fn get_unique_type_id_str_of_enum_variant_part(&mut self, enum_type_id: UniqueTypeId) -> &str {
let variant_part_type_id = format!("{}_variant_part",
self.get_unique_type_id_as_string(enum_type_id));
let interner_key = self.unique_id_interner.intern(&variant_part_type_id);
self.unique_id_interner.get(interner_key)
}
}
/// A description of some recursive type. It can either be already finished (as
/// with `FinalMetadata`) or it is not yet finished, but contains all information
/// needed to generate the missing parts of the description. See the
/// documentation section on Recursive Types at the top of this file for more
/// information.
enum RecursiveTypeDescription<'ll, 'tcx> {
UnfinishedMetadata {
unfinished_type: Ty<'tcx>,
unique_type_id: UniqueTypeId,
metadata_stub: &'ll DICompositeType,
member_holding_stub: &'ll DICompositeType,
member_description_factory: MemberDescriptionFactory<'ll, 'tcx>,
},
FinalMetadata(&'ll DICompositeType)
}
fn create_and_register_recursive_type_forward_declaration(
cx: &CodegenCx<'ll, 'tcx>,
unfinished_type: Ty<'tcx>,
unique_type_id: UniqueTypeId,
metadata_stub: &'ll DICompositeType,
member_holding_stub: &'ll DICompositeType,
member_description_factory: MemberDescriptionFactory<'ll, 'tcx>,
) -> RecursiveTypeDescription<'ll, 'tcx> {
// Insert the stub into the `TypeMap` in order to allow for recursive references.
let mut type_map = debug_context(cx).type_map.borrow_mut();
type_map.register_unique_id_with_metadata(unique_type_id, metadata_stub);
type_map.register_type_with_metadata(unfinished_type, metadata_stub);
UnfinishedMetadata {
unfinished_type,
unique_type_id,
metadata_stub,
member_holding_stub,
member_description_factory,
}
}
impl RecursiveTypeDescription<'ll, 'tcx> {
/// Finishes up the description of the type in question (mostly by providing
/// descriptions of the fields of the given type) and returns the final type
/// metadata.
fn finalize(&self, cx: &CodegenCx<'ll, 'tcx>) -> MetadataCreationResult<'ll> {
match *self {
FinalMetadata(metadata) => MetadataCreationResult::new(metadata, false),
UnfinishedMetadata {
unfinished_type,
unique_type_id,
metadata_stub,
member_holding_stub,
ref member_description_factory,
} => {
// Make sure that we have a forward declaration of the type in
// the TypeMap so that recursive references are possible. This
// will always be the case if the RecursiveTypeDescription has
// been properly created through the
// `create_and_register_recursive_type_forward_declaration()`
// function.
{
let type_map = debug_context(cx).type_map.borrow();
if type_map.find_metadata_for_unique_id(unique_type_id).is_none() ||
type_map.find_metadata_for_type(unfinished_type).is_none() {
bug!("Forward declaration of potentially recursive type \
'{:?}' was not found in TypeMap!",
unfinished_type);
}
}
// ... then create the member descriptions ...
let member_descriptions =
member_description_factory.create_member_descriptions(cx);
// ... and attach them to the stub to complete it.
set_members_of_composite_type(cx,
unfinished_type,
member_holding_stub,
member_descriptions);
return MetadataCreationResult::new(metadata_stub, true);
}
}
}
}
/// Returns from the enclosing function if the type metadata with the given
/// unique ID can be found in the type map.
macro_rules! return_if_metadata_created_in_meantime {
($cx: expr, $unique_type_id: expr) => (
if let Some(metadata) = debug_context($cx).type_map
.borrow()
.find_metadata_for_unique_id($unique_type_id)
{
return MetadataCreationResult::new(metadata, true);
}
)
}
fn fixed_vec_metadata(
cx: &CodegenCx<'ll, 'tcx>,
unique_type_id: UniqueTypeId,
array_or_slice_type: Ty<'tcx>,
element_type: Ty<'tcx>,
span: Span,
) -> MetadataCreationResult<'ll> {
let element_type_metadata = type_metadata(cx, element_type, span);
return_if_metadata_created_in_meantime!(cx, unique_type_id);
let (size, align) = cx.size_and_align_of(array_or_slice_type);
let upper_bound = match array_or_slice_type.kind {
ty::Array(_, len) => len.eval_usize(cx.tcx, ty::ParamEnv::reveal_all()) as c_longlong,
_ => -1
};
let subrange = unsafe {
Some(llvm::LLVMRustDIBuilderGetOrCreateSubrange(DIB(cx), 0, upper_bound))
};
let subscripts = create_DIArray(DIB(cx), &[subrange]);
let metadata = unsafe {
llvm::LLVMRustDIBuilderCreateArrayType(
DIB(cx),
size.bits(),
align.bits() as u32,
element_type_metadata,
subscripts)
};
return MetadataCreationResult::new(metadata, false);
}
fn vec_slice_metadata(
cx: &CodegenCx<'ll, 'tcx>,
slice_ptr_type: Ty<'tcx>,
element_type: Ty<'tcx>,
unique_type_id: UniqueTypeId,
span: Span,
) -> MetadataCreationResult<'ll> {
let data_ptr_type = cx.tcx.mk_imm_ptr(element_type);
let data_ptr_metadata = type_metadata(cx, data_ptr_type, span);
return_if_metadata_created_in_meantime!(cx, unique_type_id);
let slice_type_name = compute_debuginfo_type_name(cx.tcx, slice_ptr_type, true);
let (pointer_size, pointer_align) = cx.size_and_align_of(data_ptr_type);
let (usize_size, usize_align) = cx.size_and_align_of(cx.tcx.types.usize);
let member_descriptions = vec![
MemberDescription {
name: "data_ptr".to_owned(),
type_metadata: data_ptr_metadata,
offset: Size::ZERO,
size: pointer_size,
align: pointer_align,
flags: DIFlags::FlagZero,
discriminant: None,
},
MemberDescription {
name: "length".to_owned(),
type_metadata: type_metadata(cx, cx.tcx.types.usize, span),
offset: pointer_size,
size: usize_size,
align: usize_align,
flags: DIFlags::FlagZero,
discriminant: None,
},
];
let file_metadata = unknown_file_metadata(cx);
let metadata = composite_type_metadata(cx,
slice_ptr_type,
&slice_type_name[..],
unique_type_id,
member_descriptions,
NO_SCOPE_METADATA,
file_metadata,
span);
MetadataCreationResult::new(metadata, false)
}
fn subroutine_type_metadata(
cx: &CodegenCx<'ll, 'tcx>,
unique_type_id: UniqueTypeId,
signature: ty::PolyFnSig<'tcx>,
span: Span,
) -> MetadataCreationResult<'ll> {
let signature = cx.tcx.normalize_erasing_late_bound_regions(
ty::ParamEnv::reveal_all(),
&signature,
);
let signature_metadata: Vec<_> = iter::once(
// return type
match signature.output().kind {
ty::Tuple(ref tys) if tys.is_empty() => None,
_ => Some(type_metadata(cx, signature.output(), span))
}
).chain(
// regular arguments
signature.inputs().iter().map(|argument_type| {
Some(type_metadata(cx, argument_type, span))
})
).collect();
return_if_metadata_created_in_meantime!(cx, unique_type_id);
return MetadataCreationResult::new(
unsafe {
llvm::LLVMRustDIBuilderCreateSubroutineType(
DIB(cx),
unknown_file_metadata(cx),
create_DIArray(DIB(cx), &signature_metadata[..]))
},
false);
}
// FIXME(1563): This is all a bit of a hack because 'trait pointer' is an ill-
// defined concept. For the case of an actual trait pointer (i.e., `Box<Trait>`,
// `&Trait`), `trait_object_type` should be the whole thing (e.g, `Box<Trait>`) and
// `trait_type` should be the actual trait (e.g., `Trait`). Where the trait is part
// of a DST struct, there is no `trait_object_type` and the results of this
// function will be a little bit weird.
fn trait_pointer_metadata(
cx: &CodegenCx<'ll, 'tcx>,
trait_type: Ty<'tcx>,
trait_object_type: Option<Ty<'tcx>>,
unique_type_id: UniqueTypeId,
) -> &'ll DIType {
// The implementation provided here is a stub. It makes sure that the trait
// type is assigned the correct name, size, namespace, and source location.
// However, it does not describe the trait's methods.
let containing_scope = match trait_type.kind {
ty::Dynamic(ref data, ..) =>
data.principal_def_id().map(|did| get_namespace_for_item(cx, did)),
_ => {
bug!("debuginfo: unexpected trait-object type in \
trait_pointer_metadata(): {:?}",
trait_type);
}
};
let trait_object_type = trait_object_type.unwrap_or(trait_type);
let trait_type_name =
compute_debuginfo_type_name(cx.tcx, trait_object_type, false);
let file_metadata = unknown_file_metadata(cx);
let layout = cx.layout_of(cx.tcx.mk_mut_ptr(trait_type));
assert_eq!(abi::FAT_PTR_ADDR, 0);
assert_eq!(abi::FAT_PTR_EXTRA, 1);
let data_ptr_field = layout.field(cx, 0);
let vtable_field = layout.field(cx, 1);
let member_descriptions = vec![
MemberDescription {
name: "pointer".to_owned(),
type_metadata: type_metadata(cx,
cx.tcx.mk_mut_ptr(cx.tcx.types.u8),
syntax_pos::DUMMY_SP),
offset: layout.fields.offset(0),
size: data_ptr_field.size,
align: data_ptr_field.align.abi,
flags: DIFlags::FlagArtificial,
discriminant: None,
},
MemberDescription {
name: "vtable".to_owned(),
type_metadata: type_metadata(cx, vtable_field.ty, syntax_pos::DUMMY_SP),
offset: layout.fields.offset(1),
size: vtable_field.size,
align: vtable_field.align.abi,
flags: DIFlags::FlagArtificial,
discriminant: None,
},
];
composite_type_metadata(cx,
trait_object_type,
&trait_type_name[..],
unique_type_id,
member_descriptions,
containing_scope,
file_metadata,
syntax_pos::DUMMY_SP)
}
pub fn type_metadata(
cx: &CodegenCx<'ll, 'tcx>,
t: Ty<'tcx>,
usage_site_span: Span,
) -> &'ll DIType {
// Get the unique type ID of this type.
let unique_type_id = {
let mut type_map = debug_context(cx).type_map.borrow_mut();
// First, try to find the type in `TypeMap`. If we have seen it before, we
// can exit early here.
match type_map.find_metadata_for_type(t) {
Some(metadata) => {
return metadata;
},
None => {
// The Ty is not in the `TypeMap` but maybe we have already seen
// an equivalent type (e.g., only differing in region arguments).
// In order to find out, generate the unique type ID and look
// that up.
let unique_type_id = type_map.get_unique_type_id_of_type(cx, t);
match type_map.find_metadata_for_unique_id(unique_type_id) {
Some(metadata) => {
// There is already an equivalent type in the TypeMap.
// Register this Ty as an alias in the cache and
// return the cached metadata.
type_map.register_type_with_metadata(t, metadata);
return metadata;
},
None => {
// There really is no type metadata for this type, so
// proceed by creating it.
unique_type_id
}
}
}
}
};
debug!("type_metadata: {:?}", t);
let ptr_metadata = |ty: Ty<'tcx>| {
match ty.kind {
ty::Slice(typ) => {
Ok(vec_slice_metadata(cx, t, typ, unique_type_id, usage_site_span))
}
ty::Str => {
Ok(vec_slice_metadata(cx, t, cx.tcx.types.u8, unique_type_id, usage_site_span))
}
ty::Dynamic(..) => {
Ok(MetadataCreationResult::new(
trait_pointer_metadata(cx, ty, Some(t), unique_type_id),
false))
}
_ => {
let pointee_metadata = type_metadata(cx, ty, usage_site_span);
if let Some(metadata) = debug_context(cx).type_map
.borrow()
.find_metadata_for_unique_id(unique_type_id)
{
return Err(metadata);
}
Ok(MetadataCreationResult::new(pointer_type_metadata(cx, t, pointee_metadata),
false))
}
}
};
let MetadataCreationResult { metadata, already_stored_in_typemap } = match t.kind {
ty::Never |
ty::Bool |
ty::Char |
ty::Int(_) |
ty::Uint(_) |
ty::Float(_) => {
MetadataCreationResult::new(basic_type_metadata(cx, t), false)
}
ty::Tuple(ref elements) if elements.is_empty() => {
MetadataCreationResult::new(basic_type_metadata(cx, t), false)
}
ty::Array(typ, _) |
ty::Slice(typ) => {
fixed_vec_metadata(cx, unique_type_id, t, typ, usage_site_span)
}
ty::Str => {
fixed_vec_metadata(cx, unique_type_id, t, cx.tcx.types.i8, usage_site_span)
}
ty::Dynamic(..) => {
MetadataCreationResult::new(
trait_pointer_metadata(cx, t, None, unique_type_id),
false)
}
ty::Foreign(..) => {
MetadataCreationResult::new(
foreign_type_metadata(cx, t, unique_type_id),
false)
}
ty::RawPtr(ty::TypeAndMut{ty, ..}) |
ty::Ref(_, ty, _) => {
match ptr_metadata(ty) {
Ok(res) => res,
Err(metadata) => return metadata,
}
}
ty::Adt(def, _) if def.is_box() => {
match ptr_metadata(t.boxed_ty()) {
Ok(res) => res,
Err(metadata) => return metadata,
}
}
ty::FnDef(..) | ty::FnPtr(_) => {
if let Some(metadata) = debug_context(cx).type_map
.borrow()
.find_metadata_for_unique_id(unique_type_id)
{
return metadata;
}
// It's possible to create a self-referential
// type in Rust by using 'impl trait':
//
// fn foo() -> impl Copy { foo }
//
// See `TypeMap::remove_type` for more detals
// about the workaround.
let temp_type = {
unsafe {
// The choice of type here is pretty arbitrary -
// anything reading the debuginfo for a recursive
// type is going to see *somthing* weird - the only
// question is what exactly it will see.
let (size, align) = cx.size_and_align_of(t);
llvm::LLVMRustDIBuilderCreateBasicType(
DIB(cx),
SmallCStr::new("<recur_type>").as_ptr(),
size.bits(),
align.bits() as u32,
DW_ATE_unsigned)
}
};
let type_map = &debug_context(cx).type_map;
type_map.borrow_mut().register_type_with_metadata(t, temp_type);
let fn_metadata = subroutine_type_metadata(cx,
unique_type_id,
t.fn_sig(cx.tcx),
usage_site_span).metadata;
type_map.borrow_mut().remove_type(t);
// This is actually a function pointer, so wrap it in pointer DI.
MetadataCreationResult::new(pointer_type_metadata(cx, t, fn_metadata), false)
}
ty::Closure(def_id, substs) => {
let upvar_tys : Vec<_> = substs.as_closure().upvar_tys(def_id, cx.tcx).collect();
let containing_scope = get_namespace_for_item(cx, def_id);
prepare_tuple_metadata(cx,
t,
&upvar_tys,
unique_type_id,
usage_site_span,
Some(containing_scope)).finalize(cx)
}
ty::Generator(def_id, substs, _) => {
let upvar_tys : Vec<_> = substs
.as_generator().prefix_tys(def_id, cx.tcx).map(|t| {
cx.tcx.normalize_erasing_regions(ParamEnv::reveal_all(), t)
}).collect();
prepare_enum_metadata(cx,
t,
def_id,
unique_type_id,
usage_site_span,
upvar_tys).finalize(cx)
}
ty::Adt(def, ..) => match def.adt_kind() {
AdtKind::Struct => {
prepare_struct_metadata(cx,
t,
unique_type_id,
usage_site_span).finalize(cx)
}
AdtKind::Union => {
prepare_union_metadata(cx,
t,
unique_type_id,
usage_site_span).finalize(cx)
}
AdtKind::Enum => {
prepare_enum_metadata(cx,
t,
def.did,
unique_type_id,
usage_site_span,
vec![]).finalize(cx)
}
},
ty::Tuple(ref elements) => {
let tys: Vec<_> = elements.iter().map(|k| k.expect_ty()).collect();
prepare_tuple_metadata(cx,
t,
&tys,
unique_type_id,
usage_site_span,
NO_SCOPE_METADATA).finalize(cx)
}
_ => {
bug!("debuginfo: unexpected type in type_metadata: {:?}", t)
}
};
{
let mut type_map = debug_context(cx).type_map.borrow_mut();
if already_stored_in_typemap {
// Also make sure that we already have a `TypeMap` entry for the unique type ID.
let metadata_for_uid = match type_map.find_metadata_for_unique_id(unique_type_id) {
Some(metadata) => metadata,
None => {
span_bug!(usage_site_span,
"expected type metadata for unique \
type ID '{}' to already be in \
the `debuginfo::TypeMap` but it \
was not. (Ty = {})",
type_map.get_unique_type_id_as_string(unique_type_id),
t);
}
};
match type_map.find_metadata_for_type(t) {
Some(metadata) => {
if metadata != metadata_for_uid {
span_bug!(usage_site_span,
"mismatch between `Ty` and \
`UniqueTypeId` maps in \
`debuginfo::TypeMap`. \
UniqueTypeId={}, Ty={}",
type_map.get_unique_type_id_as_string(unique_type_id),
t);
}
}
None => {
type_map.register_type_with_metadata(t, metadata);
}
}
} else {
type_map.register_type_with_metadata(t, metadata);
type_map.register_unique_id_with_metadata(unique_type_id, metadata);
}
}
metadata
}
pub fn file_metadata(cx: &CodegenCx<'ll, '_>,
file_name: &FileName,
defining_crate: CrateNum) -> &'ll DIFile {
debug!("file_metadata: file_name: {}, defining_crate: {}",
file_name,
defining_crate);
let file_name = Some(file_name.to_string());
let directory = if defining_crate == LOCAL_CRATE {
Some(cx.sess().working_dir.0.to_string_lossy().to_string())
} else {
// If the path comes from an upstream crate we assume it has been made
// independent of the compiler's working directory one way or another.
None
};
file_metadata_raw(cx, file_name, directory)
}
pub fn unknown_file_metadata(cx: &CodegenCx<'ll, '_>) -> &'ll DIFile {
file_metadata_raw(cx, None, None)
}
fn file_metadata_raw(cx: &CodegenCx<'ll, '_>,
file_name: Option<String>,
directory: Option<String>)
-> &'ll DIFile {
let key = (file_name, directory);
match debug_context(cx).created_files.borrow_mut().entry(key) {
Entry::Occupied(o) => return o.get(),
Entry::Vacant(v) => {
let (file_name, directory) = v.key();
debug!("file_metadata: file_name: {:?}, directory: {:?}", file_name, directory);
let file_name = SmallCStr::new(
if let Some(file_name) = file_name { &file_name } else { "<unknown>" });
let directory = SmallCStr::new(
if let Some(directory) = directory { &directory } else { "" });
let file_metadata = unsafe {
llvm::LLVMRustDIBuilderCreateFile(DIB(cx),
file_name.as_ptr(),
directory.as_ptr())
};
v.insert(file_metadata);
file_metadata
}
}
}
fn basic_type_metadata(cx: &CodegenCx<'ll, 'tcx>, t: Ty<'tcx>) -> &'ll DIType {
debug!("basic_type_metadata: {:?}", t);
let (name, encoding) = match t.kind {
ty::Never => ("!", DW_ATE_unsigned),
ty::Tuple(ref elements) if elements.is_empty() =>
("()", DW_ATE_unsigned),
ty::Bool => ("bool", DW_ATE_boolean),
ty::Char => ("char", DW_ATE_unsigned_char),
ty::Int(int_ty) => {
(int_ty.name_str(), DW_ATE_signed)
},
ty::Uint(uint_ty) => {
(uint_ty.name_str(), DW_ATE_unsigned)
},
ty::Float(float_ty) => {
(float_ty.name_str(), DW_ATE_float)
},
_ => bug!("debuginfo::basic_type_metadata - `t` is invalid type")
};
let (size, align) = cx.size_and_align_of(t);
let name = SmallCStr::new(name);
let ty_metadata = unsafe {
llvm::LLVMRustDIBuilderCreateBasicType(
DIB(cx),
name.as_ptr(),
size.bits(),
align.bits() as u32,
encoding)
};
return ty_metadata;
}
fn foreign_type_metadata(
cx: &CodegenCx<'ll, 'tcx>,
t: Ty<'tcx>,
unique_type_id: UniqueTypeId,
) -> &'ll DIType {
debug!("foreign_type_metadata: {:?}", t);
let name = compute_debuginfo_type_name(cx.tcx, t, false);
create_struct_stub(cx, t, &name, unique_type_id, NO_SCOPE_METADATA)
}
fn pointer_type_metadata(
cx: &CodegenCx<'ll, 'tcx>,
pointer_type: Ty<'tcx>,
pointee_type_metadata: &'ll DIType,
) -> &'ll DIType {
let (pointer_size, pointer_align) = cx.size_and_align_of(pointer_type);
let name = compute_debuginfo_type_name(cx.tcx, pointer_type, false);
let name = SmallCStr::new(&name);
unsafe {
llvm::LLVMRustDIBuilderCreatePointerType(
DIB(cx),
pointee_type_metadata,
pointer_size.bits(),
pointer_align.bits() as u32,
name.as_ptr())
}
}
pub fn compile_unit_metadata(
tcx: TyCtxt<'_>,
codegen_unit_name: &str,
debug_context: &CrateDebugContext<'ll, '_>,
) -> &'ll DIDescriptor {
let mut name_in_debuginfo = match tcx.sess.local_crate_source_file {
Some(ref path) => path.clone(),
None => PathBuf::from(&*tcx.crate_name(LOCAL_CRATE).as_str()),
};
// The OSX linker has an idiosyncrasy where it will ignore some debuginfo
// if multiple object files with the same `DW_AT_name` are linked together.
// As a workaround we generate unique names for each object file. Those do
// not correspond to an actual source file but that should be harmless.
if tcx.sess.target.target.options.is_like_osx {
name_in_debuginfo.push("@");
name_in_debuginfo.push(codegen_unit_name);
}
debug!("compile_unit_metadata: {:?}", name_in_debuginfo);
let rustc_producer = format!(
"rustc version {}",
option_env!("CFG_VERSION").expect("CFG_VERSION"),
);
// FIXME(#41252) Remove "clang LLVM" if we can get GDB and LLVM to play nice.
let producer = format!("clang LLVM ({})", rustc_producer);
let name_in_debuginfo = name_in_debuginfo.to_string_lossy();
let name_in_debuginfo = SmallCStr::new(&name_in_debuginfo);
let work_dir = SmallCStr::new(&tcx.sess.working_dir.0.to_string_lossy());
let producer = CString::new(producer).unwrap();
let flags = "\0";
let split_name = "\0";
// FIXME(#60020):
//
// This should actually be
//
// let kind = DebugEmissionKind::from_generic(tcx.sess.opts.debuginfo);
//
// That is, we should set LLVM's emission kind to `LineTablesOnly` if
// we are compiling with "limited" debuginfo. However, some of the
// existing tools relied on slightly more debuginfo being generated than
// would be the case with `LineTablesOnly`, and we did not want to break
// these tools in a "drive-by fix", without a good idea or plan about
// what limited debuginfo should exactly look like. So for now we keep
// the emission kind as `FullDebug`.
//
// See https://github.com/rust-lang/rust/issues/60020 for details.
let kind = DebugEmissionKind::FullDebug;
assert!(tcx.sess.opts.debuginfo != DebugInfo::None);
unsafe {
let file_metadata = llvm::LLVMRustDIBuilderCreateFile(
debug_context.builder, name_in_debuginfo.as_ptr(), work_dir.as_ptr());
let unit_metadata = llvm::LLVMRustDIBuilderCreateCompileUnit(
debug_context.builder,
DW_LANG_RUST,
file_metadata,
producer.as_ptr(),
tcx.sess.opts.optimize != config::OptLevel::No,
flags.as_ptr().cast(),
0,
split_name.as_ptr().cast(),
kind);
if tcx.sess.opts.debugging_opts.profile {
let cu_desc_metadata = llvm::LLVMRustMetadataAsValue(debug_context.llcontext,
unit_metadata);
let gcov_cu_info = [
path_to_mdstring(debug_context.llcontext,
&tcx.output_filenames(LOCAL_CRATE).with_extension("gcno")),
path_to_mdstring(debug_context.llcontext,
&tcx.output_filenames(LOCAL_CRATE).with_extension("gcda")),
cu_desc_metadata,
];
let gcov_metadata = llvm::LLVMMDNodeInContext(debug_context.llcontext,
gcov_cu_info.as_ptr(),
gcov_cu_info.len() as c_uint);
let llvm_gcov_ident = const_cstr!("llvm.gcov");
llvm::LLVMAddNamedMetadataOperand(debug_context.llmod,
llvm_gcov_ident.as_ptr(),
gcov_metadata);
}
// Insert `llvm.ident` metadata on the wasm32 targets since that will
// get hooked up to the "producer" sections `processed-by` information.
if tcx.sess.opts.target_triple.triple().starts_with("wasm32") {
let name_metadata = llvm::LLVMMDStringInContext(
debug_context.llcontext,
rustc_producer.as_ptr().cast(),
rustc_producer.as_bytes().len() as c_uint,
);
llvm::LLVMAddNamedMetadataOperand(
debug_context.llmod,
const_cstr!("llvm.ident").as_ptr(),
llvm::LLVMMDNodeInContext(debug_context.llcontext, &name_metadata, 1),
);
}
return unit_metadata;
};
fn path_to_mdstring(llcx: &'ll llvm::Context, path: &Path) -> &'ll Value {
let path_str = path_to_c_string(path);
unsafe {
llvm::LLVMMDStringInContext(llcx,
path_str.as_ptr(),
path_str.as_bytes().len() as c_uint)
}
}
}
struct MetadataCreationResult<'ll> {
metadata: &'ll DIType,
already_stored_in_typemap: bool
}
impl MetadataCreationResult<'ll> {
fn new(metadata: &'ll DIType, already_stored_in_typemap: bool) -> Self {
MetadataCreationResult {
metadata,
already_stored_in_typemap,
}
}
}
/// Description of a type member, which can either be a regular field (as in
/// structs or tuples) or an enum variant.
#[derive(Debug)]
struct MemberDescription<'ll> {
name: String,
type_metadata: &'ll DIType,
offset: Size,
size: Size,
align: Align,
flags: DIFlags,
discriminant: Option<u64>,
}
impl<'ll> MemberDescription<'ll> {
fn into_metadata(self,
cx: &CodegenCx<'ll, '_>,
composite_type_metadata: &'ll DIScope) -> &'ll DIType {
let member_name = CString::new(self.name).unwrap();
unsafe {
llvm::LLVMRustDIBuilderCreateVariantMemberType(
DIB(cx),
composite_type_metadata,
member_name.as_ptr(),
unknown_file_metadata(cx),
UNKNOWN_LINE_NUMBER,
self.size.bits(),
self.align.bits() as u32,
self.offset.bits(),
match self.discriminant {
None => None,
Some(value) => Some(cx.const_u64(value)),
},
self.flags,
self.type_metadata)
}
}
}
/// A factory for `MemberDescription`s. It produces a list of member descriptions
/// for some record-like type. `MemberDescriptionFactory`s are used to defer the
/// creation of type member descriptions in order to break cycles arising from
/// recursive type definitions.
enum MemberDescriptionFactory<'ll, 'tcx> {
StructMDF(StructMemberDescriptionFactory<'tcx>),
TupleMDF(TupleMemberDescriptionFactory<'tcx>),
EnumMDF(EnumMemberDescriptionFactory<'ll, 'tcx>),
UnionMDF(UnionMemberDescriptionFactory<'tcx>),
VariantMDF(VariantMemberDescriptionFactory<'ll, 'tcx>)
}
impl MemberDescriptionFactory<'ll, 'tcx> {
fn create_member_descriptions(&self, cx: &CodegenCx<'ll, 'tcx>)
-> Vec<MemberDescription<'ll>> {
match *self {
StructMDF(ref this) => {
this.create_member_descriptions(cx)
}
TupleMDF(ref this) => {
this.create_member_descriptions(cx)
}
EnumMDF(ref this) => {
this.create_member_descriptions(cx)
}
UnionMDF(ref this) => {
this.create_member_descriptions(cx)
}
VariantMDF(ref this) => {
this.create_member_descriptions(cx)
}
}
}
}
//=-----------------------------------------------------------------------------
// Structs
//=-----------------------------------------------------------------------------
/// Creates `MemberDescription`s for the fields of a struct.
struct StructMemberDescriptionFactory<'tcx> {
ty: Ty<'tcx>,
variant: &'tcx ty::VariantDef,
span: Span,
}
impl<'tcx> StructMemberDescriptionFactory<'tcx> {
fn create_member_descriptions(&self, cx: &CodegenCx<'ll, 'tcx>)
-> Vec<MemberDescription<'ll>> {
let layout = cx.layout_of(self.ty);
self.variant.fields.iter().enumerate().map(|(i, f)| {
let name = if self.variant.ctor_kind == CtorKind::Fn {
format!("__{}", i)
} else {
f.ident.to_string()
};
let field = layout.field(cx, i);
MemberDescription {
name,
type_metadata: type_metadata(cx, field.ty, self.span),
offset: layout.fields.offset(i),
size: field.size,
align: field.align.abi,
flags: DIFlags::FlagZero,
discriminant: None,
}
}).collect()
}
}
fn prepare_struct_metadata(
cx: &CodegenCx<'ll, 'tcx>,
struct_type: Ty<'tcx>,
unique_type_id: UniqueTypeId,
span: Span,
) -> RecursiveTypeDescription<'ll, 'tcx> {
let struct_name = compute_debuginfo_type_name(cx.tcx, struct_type, false);
let (struct_def_id, variant) = match struct_type.kind {
ty::Adt(def, _) => (def.did, def.non_enum_variant()),
_ => bug!("prepare_struct_metadata on a non-ADT")
};
let containing_scope = get_namespace_for_item(cx, struct_def_id);
let struct_metadata_stub = create_struct_stub(cx,
struct_type,
&struct_name,
unique_type_id,
Some(containing_scope));
create_and_register_recursive_type_forward_declaration(
cx,
struct_type,
unique_type_id,
struct_metadata_stub,
struct_metadata_stub,
StructMDF(StructMemberDescriptionFactory {
ty: struct_type,
variant,
span,
})
)
}
//=-----------------------------------------------------------------------------
// Tuples
//=-----------------------------------------------------------------------------
/// Creates `MemberDescription`s for the fields of a tuple.
struct TupleMemberDescriptionFactory<'tcx> {
ty: Ty<'tcx>,
component_types: Vec<Ty<'tcx>>,
span: Span,
}
impl<'tcx> TupleMemberDescriptionFactory<'tcx> {
fn create_member_descriptions(&self, cx: &CodegenCx<'ll, 'tcx>)
-> Vec<MemberDescription<'ll>> {
let layout = cx.layout_of(self.ty);
self.component_types.iter().enumerate().map(|(i, &component_type)| {
let (size, align) = cx.size_and_align_of(component_type);
MemberDescription {
name: format!("__{}", i),
type_metadata: type_metadata(cx, component_type, self.span),
offset: layout.fields.offset(i),
size,
align,
flags: DIFlags::FlagZero,
discriminant: None,
}
}).collect()
}
}
fn prepare_tuple_metadata(
cx: &CodegenCx<'ll, 'tcx>,
tuple_type: Ty<'tcx>,
component_types: &[Ty<'tcx>],
unique_type_id: UniqueTypeId,
span: Span,
containing_scope: Option<&'ll DIScope>,
) -> RecursiveTypeDescription<'ll, 'tcx> {
let tuple_name = compute_debuginfo_type_name(cx.tcx, tuple_type, false);
let struct_stub = create_struct_stub(cx,
tuple_type,
&tuple_name[..],
unique_type_id,
containing_scope);
create_and_register_recursive_type_forward_declaration(
cx,
tuple_type,
unique_type_id,
struct_stub,
struct_stub,
TupleMDF(TupleMemberDescriptionFactory {
ty: tuple_type,
component_types: component_types.to_vec(),
span,
})
)
}
//=-----------------------------------------------------------------------------
// Unions
//=-----------------------------------------------------------------------------
struct UnionMemberDescriptionFactory<'tcx> {
layout: TyLayout<'tcx>,
variant: &'tcx ty::VariantDef,
span: Span,
}
impl<'tcx> UnionMemberDescriptionFactory<'tcx> {
fn create_member_descriptions(&self, cx: &CodegenCx<'ll, 'tcx>)
-> Vec<MemberDescription<'ll>> {
self.variant.fields.iter().enumerate().map(|(i, f)| {
let field = self.layout.field(cx, i);
MemberDescription {
name: f.ident.to_string(),
type_metadata: type_metadata(cx, field.ty, self.span),
offset: Size::ZERO,
size: field.size,
align: field.align.abi,
flags: DIFlags::FlagZero,
discriminant: None,
}
}).collect()
}
}
fn prepare_union_metadata(
cx: &CodegenCx<'ll, 'tcx>,
union_type: Ty<'tcx>,
unique_type_id: UniqueTypeId,
span: Span,
) -> RecursiveTypeDescription<'ll, 'tcx> {
let union_name = compute_debuginfo_type_name(cx.tcx, union_type, false);
let (union_def_id, variant) = match union_type.kind {
ty::Adt(def, _) => (def.did, def.non_enum_variant()),
_ => bug!("prepare_union_metadata on a non-ADT")
};
let containing_scope = get_namespace_for_item(cx, union_def_id);
let union_metadata_stub = create_union_stub(cx,
union_type,
&union_name,
unique_type_id,
containing_scope);
create_and_register_recursive_type_forward_declaration(
cx,
union_type,
unique_type_id,
union_metadata_stub,
union_metadata_stub,
UnionMDF(UnionMemberDescriptionFactory {
layout: cx.layout_of(union_type),
variant,
span,
})
)
}
//=-----------------------------------------------------------------------------
// Enums
//=-----------------------------------------------------------------------------
/// DWARF variant support is only available starting in LLVM 8.
/// Although the earlier enum debug info output did not work properly
/// in all situations, it is better for the time being to continue to
/// sometimes emit the old style rather than emit something completely
/// useless when rust is compiled against LLVM 6 or older. LLVM 7
/// contains an early version of the DWARF variant support, and will
/// crash when handling the new debug info format. This function
/// decides which representation will be emitted.
fn use_enum_fallback(cx: &CodegenCx<'_, '_>) -> bool {
// On MSVC we have to use the fallback mode, because LLVM doesn't
// lower variant parts to PDB.
return cx.sess().target.target.options.is_like_msvc
// LLVM version 7 did not release with an important bug fix;
// but the required patch is in the LLVM 8. Rust LLVM reports
// 8 as well.
|| llvm_util::get_major_version() < 8;
}
// FIXME(eddyb) maybe precompute this? Right now it's computed once
// per generator monomorphization, but it doesn't depend on substs.
fn generator_layout_and_saved_local_names(
tcx: TyCtxt<'tcx>,
def_id: DefId,
) -> (&'tcx GeneratorLayout<'tcx>, IndexVec<mir::GeneratorSavedLocal, Option<ast::Name>>) {
let body = tcx.optimized_mir(def_id);
let generator_layout = body.generator_layout.as_ref().unwrap();
let mut generator_saved_local_names =
IndexVec::from_elem(None, &generator_layout.field_tys);
let state_arg = mir::PlaceBase::Local(mir::Local::new(1));
for var in &body.var_debug_info {
if var.place.base != state_arg {
continue;
}
match var.place.projection[..] {
[
// Deref of the `Pin<&mut Self>` state argument.
mir::ProjectionElem::Field(..),
mir::ProjectionElem::Deref,
// Field of a variant of the state.
mir::ProjectionElem::Downcast(_, variant),
mir::ProjectionElem::Field(field, _),
] => {
let name = &mut generator_saved_local_names[
generator_layout.variant_fields[variant][field]
];
if name.is_none() {
name.replace(var.name);
}
}
_ => {}
}
}
(generator_layout, generator_saved_local_names)
}
/// Describes the members of an enum value; an enum is described as a union of
/// structs in DWARF. This `MemberDescriptionFactory` provides the description for
/// the members of this union; so for every variant of the given enum, this
/// factory will produce one `MemberDescription` (all with no name and a fixed
/// offset of zero bytes).
struct EnumMemberDescriptionFactory<'ll, 'tcx> {
enum_type: Ty<'tcx>,
layout: TyLayout<'tcx>,
discriminant_type_metadata: Option<&'ll DIType>,
containing_scope: &'ll DIScope,
span: Span,
}
impl EnumMemberDescriptionFactory<'ll, 'tcx> {
fn create_member_descriptions(&self, cx: &CodegenCx<'ll, 'tcx>)
-> Vec<MemberDescription<'ll>> {
let generator_variant_info_data = match self.enum_type.kind {
ty::Generator(def_id, ..) => {
Some(generator_layout_and_saved_local_names(cx.tcx, def_id))
}
_ => None,
};
let variant_info_for = |index: VariantIdx| {
match self.enum_type.kind {
ty::Adt(adt, _) => VariantInfo::Adt(&adt.variants[index]),
ty::Generator(_, substs, _) => {
let (generator_layout, generator_saved_local_names) =
generator_variant_info_data.as_ref().unwrap();
VariantInfo::Generator {
substs,
generator_layout: *generator_layout,
generator_saved_local_names,
variant_index: index,
}
}
_ => bug!(),
}
};
// This will always find the metadata in the type map.
let fallback = use_enum_fallback(cx);
let self_metadata = if fallback {
self.containing_scope
} else {
type_metadata(cx, self.enum_type, self.span)
};
match self.layout.variants {
layout::Variants::Single { index } => {
if let ty::Adt(adt, _) = &self.enum_type.kind {
if adt.variants.is_empty() {
return vec![];
}
}
let variant_info = variant_info_for(index);
let (variant_type_metadata, member_description_factory) =
describe_enum_variant(cx,
self.layout,
variant_info,
NoDiscriminant,
self_metadata,
self.span);
let member_descriptions =
member_description_factory.create_member_descriptions(cx);
set_members_of_composite_type(cx,
self.enum_type,
variant_type_metadata,
member_descriptions);
vec![
MemberDescription {
name: if fallback {
String::new()
} else {
variant_info.variant_name()
},
type_metadata: variant_type_metadata,
offset: Size::ZERO,
size: self.layout.size,
align: self.layout.align.abi,
flags: DIFlags::FlagZero,
discriminant: None,
}
]
}
layout::Variants::Multiple {
discr_kind: layout::DiscriminantKind::Tag,
discr_index,
ref variants,
..
} => {
let discriminant_info = if fallback {
RegularDiscriminant {
discr_field: Field::from(discr_index),
discr_type_metadata: self.discriminant_type_metadata.unwrap()
}
} else {
// This doesn't matter in this case.
NoDiscriminant
};
variants.iter_enumerated().map(|(i, _)| {
let variant = self.layout.for_variant(cx, i);
let variant_info = variant_info_for(i);
let (variant_type_metadata, member_desc_factory) =
describe_enum_variant(cx,
variant,
variant_info,
discriminant_info,
self_metadata,
self.span);
let member_descriptions = member_desc_factory
.create_member_descriptions(cx);
set_members_of_composite_type(cx,
self.enum_type,
variant_type_metadata,
member_descriptions);
MemberDescription {
name: if fallback {
String::new()
} else {
variant_info.variant_name()
},
type_metadata: variant_type_metadata,
offset: Size::ZERO,
size: self.layout.size,
align: self.layout.align.abi,
flags: DIFlags::FlagZero,
discriminant: Some(
self.layout.ty.discriminant_for_variant(cx.tcx, i).unwrap().val as u64
),
}
}).collect()
}
layout::Variants::Multiple {
discr_kind: layout::DiscriminantKind::Niche {
ref niche_variants,
niche_start,
dataful_variant,
},
ref discr,
ref variants,
discr_index,
} => {
if fallback {
let variant = self.layout.for_variant(cx, dataful_variant);
// Create a description of the non-null variant.
let (variant_type_metadata, member_description_factory) =
describe_enum_variant(cx,
variant,
variant_info_for(dataful_variant),
OptimizedDiscriminant,
self.containing_scope,
self.span);
let variant_member_descriptions =
member_description_factory.create_member_descriptions(cx);
set_members_of_composite_type(cx,
self.enum_type,
variant_type_metadata,
variant_member_descriptions);
// Encode the information about the null variant in the union
// member's name.
let mut name = String::from("RUST$ENCODED$ENUM$");
// Right now it's not even going to work for `niche_start > 0`,
// and for multiple niche variants it only supports the first.
fn compute_field_path<'a, 'tcx>(cx: &CodegenCx<'a, 'tcx>,
name: &mut String,
layout: TyLayout<'tcx>,
offset: Size,
size: Size) {
for i in 0..layout.fields.count() {
let field_offset = layout.fields.offset(i);
if field_offset > offset {
continue;
}
let inner_offset = offset - field_offset;
let field = layout.field(cx, i);
if inner_offset + size <= field.size {
write!(name, "{}$", i).unwrap();
compute_field_path(cx, name, field, inner_offset, size);
}
}
}
compute_field_path(cx, &mut name,
self.layout,
self.layout.fields.offset(discr_index),
self.layout.field(cx, discr_index).size);
variant_info_for(*niche_variants.start()).map_struct_name(|variant_name| {
name.push_str(variant_name);
});
// Create the (singleton) list of descriptions of union members.
vec![
MemberDescription {
name,
type_metadata: variant_type_metadata,
offset: Size::ZERO,
size: variant.size,
align: variant.align.abi,
flags: DIFlags::FlagZero,
discriminant: None,
}
]
} else {
variants.iter_enumerated().map(|(i, _)| {
let variant = self.layout.for_variant(cx, i);
let variant_info = variant_info_for(i);
let (variant_type_metadata, member_desc_factory) =
describe_enum_variant(cx,
variant,
variant_info,
OptimizedDiscriminant,
self_metadata,
self.span);
let member_descriptions = member_desc_factory
.create_member_descriptions(cx);
set_members_of_composite_type(cx,
self.enum_type,
variant_type_metadata,
member_descriptions);
let niche_value = if i == dataful_variant {
None
} else {
let value = (i.as_u32() as u128)
.wrapping_sub(niche_variants.start().as_u32() as u128)
.wrapping_add(niche_start);
let value = truncate(value, discr.value.size(cx));
// NOTE(eddyb) do *NOT* remove this assert, until
// we pass the full 128-bit value to LLVM, otherwise
// truncation will be silent and remain undetected.
assert_eq!(value as u64 as u128, value);
Some(value as u64)
};
MemberDescription {
name: variant_info.variant_name(),
type_metadata: variant_type_metadata,
offset: Size::ZERO,
size: self.layout.size,
align: self.layout.align.abi,
flags: DIFlags::FlagZero,
discriminant: niche_value,
}
}).collect()
}
}
}
}
}
// Creates `MemberDescription`s for the fields of a single enum variant.
struct VariantMemberDescriptionFactory<'ll, 'tcx> {
/// Cloned from the `layout::Struct` describing the variant.
offsets: Vec<layout::Size>,
args: Vec<(String, Ty<'tcx>)>,
discriminant_type_metadata: Option<&'ll DIType>,
span: Span,
}
impl VariantMemberDescriptionFactory<'ll, 'tcx> {
fn create_member_descriptions(&self, cx: &CodegenCx<'ll, 'tcx>)
-> Vec<MemberDescription<'ll>> {
self.args.iter().enumerate().map(|(i, &(ref name, ty))| {
let (size, align) = cx.size_and_align_of(ty);
MemberDescription {
name: name.to_string(),
type_metadata: if use_enum_fallback(cx) {
match self.discriminant_type_metadata {
// Discriminant is always the first field of our variant
// when using the enum fallback.
Some(metadata) if i == 0 => metadata,
_ => type_metadata(cx, ty, self.span)
}
} else {
type_metadata(cx, ty, self.span)
},
offset: self.offsets[i],
size,
align,
flags: DIFlags::FlagZero,
discriminant: None,
}
}).collect()
}
}
#[derive(Copy, Clone)]
enum EnumDiscriminantInfo<'ll> {
RegularDiscriminant{ discr_field: Field, discr_type_metadata: &'ll DIType },
OptimizedDiscriminant,
NoDiscriminant
}
#[derive(Copy, Clone)]
enum VariantInfo<'a, 'tcx> {
Adt(&'tcx ty::VariantDef),
Generator {
substs: SubstsRef<'tcx>,
generator_layout: &'tcx GeneratorLayout<'tcx>,
generator_saved_local_names: &'a IndexVec<mir::GeneratorSavedLocal, Option<ast::Name>>,
variant_index: VariantIdx,
},
}
impl<'tcx> VariantInfo<'_, 'tcx> {
fn map_struct_name<R>(&self, f: impl FnOnce(&str) -> R) -> R {
match self {
VariantInfo::Adt(variant) => f(&variant.ident.as_str()),
VariantInfo::Generator { substs, variant_index, .. } =>
f(&substs.as_generator().variant_name(*variant_index)),
}
}
fn variant_name(&self) -> String {
match self {
VariantInfo::Adt(variant) => variant.ident.to_string(),
VariantInfo::Generator { variant_index, .. } => {
// Since GDB currently prints out the raw discriminant along
// with every variant, make each variant name be just the value
// of the discriminant. The struct name for the variant includes
// the actual variant description.
format!("{}", variant_index.as_usize())
}
}
}
fn field_name(&self, i: usize) -> String {
let field_name = match *self {
VariantInfo::Adt(variant) if variant.ctor_kind != CtorKind::Fn =>
Some(variant.fields[i].ident.name),
VariantInfo::Generator {
generator_layout,
generator_saved_local_names,
variant_index,
..
} => generator_saved_local_names[
generator_layout.variant_fields[variant_index][i.into()]
],
_ => None,
};
field_name.map(|name| name.to_string()).unwrap_or_else(|| format!("__{}", i))
}
}
/// Returns a tuple of (1) `type_metadata_stub` of the variant, (2) a
/// `MemberDescriptionFactory` for producing the descriptions of the
/// fields of the variant. This is a rudimentary version of a full
/// `RecursiveTypeDescription`.
fn describe_enum_variant(
cx: &CodegenCx<'ll, 'tcx>,
layout: layout::TyLayout<'tcx>,
variant: VariantInfo<'_, 'tcx>,
discriminant_info: EnumDiscriminantInfo<'ll>,
containing_scope: &'ll DIScope,
span: Span,
) -> (&'ll DICompositeType, MemberDescriptionFactory<'ll, 'tcx>) {
let metadata_stub = variant.map_struct_name(|variant_name| {
let unique_type_id = debug_context(cx).type_map
.borrow_mut()
.get_unique_type_id_of_enum_variant(
cx,
layout.ty,
&variant_name);
create_struct_stub(cx,
layout.ty,
&variant_name,
unique_type_id,
Some(containing_scope))
});
// Build an array of (field name, field type) pairs to be captured in the factory closure.
let (offsets, args) = if use_enum_fallback(cx) {
// If this is not a univariant enum, there is also the discriminant field.
let (discr_offset, discr_arg) = match discriminant_info {
RegularDiscriminant { discr_field, .. } => {
// We have the layout of an enum variant, we need the layout of the outer enum
let enum_layout = cx.layout_of(layout.ty);
let offset = enum_layout.fields.offset(discr_field.as_usize());
let args = (
"RUST$ENUM$DISR".to_owned(),
enum_layout.field(cx, discr_field.as_usize()).ty);
(Some(offset), Some(args))
}
_ => (None, None),
};
(
discr_offset.into_iter().chain((0..layout.fields.count()).map(|i| {
layout.fields.offset(i)
})).collect(),
discr_arg.into_iter().chain((0..layout.fields.count()).map(|i| {
(variant.field_name(i), layout.field(cx, i).ty)
})).collect()
)
} else {
(
(0..layout.fields.count()).map(|i| {
layout.fields.offset(i)
}).collect(),
(0..layout.fields.count()).map(|i| {
(variant.field_name(i), layout.field(cx, i).ty)
}).collect()
)
};
let member_description_factory =
VariantMDF(VariantMemberDescriptionFactory {
offsets,
args,
discriminant_type_metadata: match discriminant_info {
RegularDiscriminant { discr_type_metadata, .. } => {
Some(discr_type_metadata)
}
_ => None
},
span,
});
(metadata_stub, member_description_factory)
}
fn prepare_enum_metadata(
cx: &CodegenCx<'ll, 'tcx>,
enum_type: Ty<'tcx>,
enum_def_id: DefId,
unique_type_id: UniqueTypeId,
span: Span,
outer_field_tys: Vec<Ty<'tcx>>,
) -> RecursiveTypeDescription<'ll, 'tcx> {
let enum_name = compute_debuginfo_type_name(cx.tcx, enum_type, false);
let containing_scope = get_namespace_for_item(cx, enum_def_id);
// FIXME: This should emit actual file metadata for the enum, but we
// currently can't get the necessary information when it comes to types
// imported from other crates. Formerly we violated the ODR when performing
// LTO because we emitted debuginfo for the same type with varying file
// metadata, so as a workaround we pretend that the type comes from
// <unknown>
let file_metadata = unknown_file_metadata(cx);
let discriminant_type_metadata = |discr: layout::Primitive| {
let enumerators_metadata: Vec<_> = match enum_type.kind {
ty::Adt(def, _) => def
.discriminants(cx.tcx)
.zip(&def.variants)
.map(|((_, discr), v)| {
let name = SmallCStr::new(&v.ident.as_str());
unsafe {
Some(llvm::LLVMRustDIBuilderCreateEnumerator(
DIB(cx),
name.as_ptr(),
// FIXME: what if enumeration has i128 discriminant?
discr.val as u64))
}
})
.collect(),
ty::Generator(_, substs, _) => substs
.as_generator()
.variant_range(enum_def_id, cx.tcx)
.map(|variant_index| {
let name = SmallCStr::new(&substs.as_generator().variant_name(variant_index));
unsafe {
Some(llvm::LLVMRustDIBuilderCreateEnumerator(
DIB(cx),
name.as_ptr(),
// FIXME: what if enumeration has i128 discriminant?
variant_index.as_usize() as u64))
}
})
.collect(),
_ => bug!(),
};
let disr_type_key = (enum_def_id, discr);
let cached_discriminant_type_metadata = debug_context(cx).created_enum_disr_types
.borrow()
.get(&disr_type_key).cloned();
match cached_discriminant_type_metadata {
Some(discriminant_type_metadata) => discriminant_type_metadata,
None => {
let (discriminant_size, discriminant_align) =
(discr.size(cx), discr.align(cx));
let discriminant_base_type_metadata =
type_metadata(cx, discr.to_ty(cx.tcx), syntax_pos::DUMMY_SP);
let discriminant_name = match enum_type.kind {
ty::Adt(..) => SmallCStr::new(&cx.tcx.item_name(enum_def_id).as_str()),
ty::Generator(..) => SmallCStr::new(&enum_name),
_ => bug!(),
};
let discriminant_type_metadata = unsafe {
llvm::LLVMRustDIBuilderCreateEnumerationType(
DIB(cx),
containing_scope,
discriminant_name.as_ptr(),
file_metadata,
UNKNOWN_LINE_NUMBER,
discriminant_size.bits(),
discriminant_align.abi.bits() as u32,
create_DIArray(DIB(cx), &enumerators_metadata),
discriminant_base_type_metadata, true)
};
debug_context(cx).created_enum_disr_types
.borrow_mut()
.insert(disr_type_key, discriminant_type_metadata);
discriminant_type_metadata
}
}
};
let layout = cx.layout_of(enum_type);
match (&layout.abi, &layout.variants) {
(&layout::Abi::Scalar(_), &layout::Variants::Multiple {
discr_kind: layout::DiscriminantKind::Tag,
ref discr,
..
}) => return FinalMetadata(discriminant_type_metadata(discr.value)),
_ => {}
}
let enum_name = SmallCStr::new(&enum_name);
let unique_type_id_str = SmallCStr::new(
debug_context(cx).type_map.borrow().get_unique_type_id_as_string(unique_type_id)
);
if use_enum_fallback(cx) {
let discriminant_type_metadata = match layout.variants {
layout::Variants::Single { .. } |
layout::Variants::Multiple {
discr_kind: layout::DiscriminantKind::Niche { .. },
..
} => None,
layout::Variants::Multiple {
discr_kind: layout::DiscriminantKind::Tag,
ref discr,
..
} => {
Some(discriminant_type_metadata(discr.value))
}
};
let enum_metadata = unsafe {
llvm::LLVMRustDIBuilderCreateUnionType(
DIB(cx),
containing_scope,
enum_name.as_ptr(),
file_metadata,
UNKNOWN_LINE_NUMBER,
layout.size.bits(),
layout.align.abi.bits() as u32,
DIFlags::FlagZero,
None,
0, // RuntimeLang
unique_type_id_str.as_ptr())
};
return create_and_register_recursive_type_forward_declaration(
cx,
enum_type,
unique_type_id,
enum_metadata,
enum_metadata,
EnumMDF(EnumMemberDescriptionFactory {
enum_type,
layout,
discriminant_type_metadata,
containing_scope,
span,
}),
);
}
let discriminator_name = match &enum_type.kind {
ty::Generator(..) => Some(SmallCStr::new(&"__state")),
_ => None,
};
let discriminator_name = discriminator_name.map(|n| n.as_ptr()).unwrap_or(ptr::null_mut());
let discriminator_metadata = match layout.variants {
// A single-variant enum has no discriminant.
layout::Variants::Single { .. } => None,
layout::Variants::Multiple {
discr_kind: layout::DiscriminantKind::Niche { .. },
ref discr,
discr_index,
..
} => {
// Find the integer type of the correct size.
let size = discr.value.size(cx);
let align = discr.value.align(cx);
let discr_type = match discr.value {
layout::Int(t, _) => t,
layout::F32 => Integer::I32,
layout::F64 => Integer::I64,
layout::Pointer => cx.data_layout().ptr_sized_integer(),
}.to_ty(cx.tcx, false);
let discr_metadata = basic_type_metadata(cx, discr_type);
unsafe {
Some(llvm::LLVMRustDIBuilderCreateMemberType(
DIB(cx),
containing_scope,
discriminator_name,
file_metadata,
UNKNOWN_LINE_NUMBER,
size.bits(),
align.abi.bits() as u32,
layout.fields.offset(discr_index).bits(),
DIFlags::FlagArtificial,
discr_metadata))
}
},
layout::Variants::Multiple {
discr_kind: layout::DiscriminantKind::Tag,
ref discr,
discr_index,
..
} => {
let discr_type = discr.value.to_ty(cx.tcx);
let (size, align) = cx.size_and_align_of(discr_type);
let discr_metadata = basic_type_metadata(cx, discr_type);
unsafe {
Some(llvm::LLVMRustDIBuilderCreateMemberType(
DIB(cx),
containing_scope,
discriminator_name,
file_metadata,
UNKNOWN_LINE_NUMBER,
size.bits(),
align.bits() as u32,
layout.fields.offset(discr_index).bits(),
DIFlags::FlagArtificial,
discr_metadata))
}
},
};
let mut outer_fields = match layout.variants {
layout::Variants::Single { .. } => vec![],
layout::Variants::Multiple { .. } => {
let tuple_mdf = TupleMemberDescriptionFactory {
ty: enum_type,
component_types: outer_field_tys,
span
};
tuple_mdf
.create_member_descriptions(cx)
.into_iter()
.map(|desc| Some(desc.into_metadata(cx, containing_scope)))
.collect()
}
};
let variant_part_unique_type_id_str = SmallCStr::new(
debug_context(cx).type_map
.borrow_mut()
.get_unique_type_id_str_of_enum_variant_part(unique_type_id)
);
let empty_array = create_DIArray(DIB(cx), &[]);
let variant_part = unsafe {
llvm::LLVMRustDIBuilderCreateVariantPart(
DIB(cx),
containing_scope,
ptr::null_mut(),
file_metadata,
UNKNOWN_LINE_NUMBER,
layout.size.bits(),
layout.align.abi.bits() as u32,
DIFlags::FlagZero,
discriminator_metadata,
empty_array,
variant_part_unique_type_id_str.as_ptr())
};
outer_fields.push(Some(variant_part));
// The variant part must be wrapped in a struct according to DWARF.
let type_array = create_DIArray(DIB(cx), &outer_fields);
let struct_wrapper = unsafe {
llvm::LLVMRustDIBuilderCreateStructType(
DIB(cx),
Some(containing_scope),
enum_name.as_ptr(),
file_metadata,
UNKNOWN_LINE_NUMBER,
layout.size.bits(),
layout.align.abi.bits() as u32,
DIFlags::FlagZero,
None,
type_array,
0,
None,
unique_type_id_str.as_ptr())
};
return create_and_register_recursive_type_forward_declaration(
cx,
enum_type,
unique_type_id,
struct_wrapper,
variant_part,
EnumMDF(EnumMemberDescriptionFactory {
enum_type,
layout,
discriminant_type_metadata: None,
containing_scope,
span,
}),
);
}
/// Creates debug information for a composite type, that is, anything that
/// results in a LLVM struct.
///
/// Examples of Rust types to use this are: structs, tuples, boxes, vecs, and enums.
fn composite_type_metadata(
cx: &CodegenCx<'ll, 'tcx>,
composite_type: Ty<'tcx>,
composite_type_name: &str,
composite_type_unique_id: UniqueTypeId,
member_descriptions: Vec<MemberDescription<'ll>>,
containing_scope: Option<&'ll DIScope>,
// Ignore source location information as long as it
// can't be reconstructed for non-local crates.
_file_metadata: &'ll DIFile,
_definition_span: Span,
) -> &'ll DICompositeType {
// Create the (empty) struct metadata node ...
let composite_type_metadata = create_struct_stub(cx,
composite_type,
composite_type_name,
composite_type_unique_id,
containing_scope);
// ... and immediately create and add the member descriptions.
set_members_of_composite_type(cx,
composite_type,
composite_type_metadata,
member_descriptions);
composite_type_metadata
}
fn set_members_of_composite_type(cx: &CodegenCx<'ll, 'tcx>,
composite_type: Ty<'tcx>,
composite_type_metadata: &'ll DICompositeType,
member_descriptions: Vec<MemberDescription<'ll>>) {
// In some rare cases LLVM metadata uniquing would lead to an existing type
// description being used instead of a new one created in
// create_struct_stub. This would cause a hard to trace assertion in
// DICompositeType::SetTypeArray(). The following check makes sure that we
// get a better error message if this should happen again due to some
// regression.
{
let mut composite_types_completed =
debug_context(cx).composite_types_completed.borrow_mut();
if !composite_types_completed.insert(&composite_type_metadata) {
bug!("debuginfo::set_members_of_composite_type() - \
Already completed forward declaration re-encountered.");
}
}
let member_metadata: Vec<_> = member_descriptions
.into_iter()
.map(|desc| Some(desc.into_metadata(cx, composite_type_metadata)))
.collect();
let type_params = compute_type_parameters(cx, composite_type);
unsafe {
let type_array = create_DIArray(DIB(cx), &member_metadata[..]);
llvm::LLVMRustDICompositeTypeReplaceArrays(
DIB(cx), composite_type_metadata, Some(type_array), type_params);
}
}
/// Computes the type parameters for a type, if any, for the given metadata.
fn compute_type_parameters(cx: &CodegenCx<'ll, 'tcx>, ty: Ty<'tcx>) -> Option<&'ll DIArray> {
if let ty::Adt(def, substs) = ty.kind {
if !substs.types().next().is_none() {
let generics = cx.tcx.generics_of(def.did);
let names = get_parameter_names(cx, generics);
let template_params: Vec<_> = substs.iter().zip(names).filter_map(|(kind, name)| {
if let GenericArgKind::Type(ty) = kind.unpack() {
let actual_type = cx.tcx.normalize_erasing_regions(ParamEnv::reveal_all(), ty);
let actual_type_metadata =
type_metadata(cx, actual_type, syntax_pos::DUMMY_SP);
let name = SmallCStr::new(&name.as_str());
Some(unsafe {
Some(llvm::LLVMRustDIBuilderCreateTemplateTypeParameter(
DIB(cx),
None,
name.as_ptr(),
actual_type_metadata,
unknown_file_metadata(cx),
0,
0,
))
})
} else {
None
}
}).collect();
return Some(create_DIArray(DIB(cx), &template_params[..]));
}
}
return Some(create_DIArray(DIB(cx), &[]));
fn get_parameter_names(cx: &CodegenCx<'_, '_>,
generics: &ty::Generics)
-> Vec<Symbol> {
let mut names = generics.parent.map_or(vec![], |def_id| {
get_parameter_names(cx, cx.tcx.generics_of(def_id))
});
names.extend(generics.params.iter().map(|param| param.name));
names
}
}
/// A convenience wrapper around `LLVMRustDIBuilderCreateStructType()`. Does not do
/// any caching, does not add any fields to the struct. This can be done later
/// with `set_members_of_composite_type()`.
fn create_struct_stub(
cx: &CodegenCx<'ll, 'tcx>,
struct_type: Ty<'tcx>,
struct_type_name: &str,
unique_type_id: UniqueTypeId,
containing_scope: Option<&'ll DIScope>,
) -> &'ll DICompositeType {
let (struct_size, struct_align) = cx.size_and_align_of(struct_type);
let name = SmallCStr::new(struct_type_name);
let unique_type_id = SmallCStr::new(
debug_context(cx).type_map.borrow().get_unique_type_id_as_string(unique_type_id)
);
let metadata_stub = unsafe {
// `LLVMRustDIBuilderCreateStructType()` wants an empty array. A null
// pointer will lead to hard to trace and debug LLVM assertions
// later on in `llvm/lib/IR/Value.cpp`.
let empty_array = create_DIArray(DIB(cx), &[]);
llvm::LLVMRustDIBuilderCreateStructType(
DIB(cx),
containing_scope,
name.as_ptr(),
unknown_file_metadata(cx),
UNKNOWN_LINE_NUMBER,
struct_size.bits(),
struct_align.bits() as u32,
DIFlags::FlagZero,
None,
empty_array,
0,
None,
unique_type_id.as_ptr())
};
metadata_stub
}
fn create_union_stub(
cx: &CodegenCx<'ll, 'tcx>,
union_type: Ty<'tcx>,
union_type_name: &str,
unique_type_id: UniqueTypeId,
containing_scope: &'ll DIScope,
) -> &'ll DICompositeType {
let (union_size, union_align) = cx.size_and_align_of(union_type);
let name = SmallCStr::new(union_type_name);
let unique_type_id = SmallCStr::new(
debug_context(cx).type_map.borrow().get_unique_type_id_as_string(unique_type_id)
);
let metadata_stub = unsafe {
// `LLVMRustDIBuilderCreateUnionType()` wants an empty array. A null
// pointer will lead to hard to trace and debug LLVM assertions
// later on in `llvm/lib/IR/Value.cpp`.
let empty_array = create_DIArray(DIB(cx), &[]);
llvm::LLVMRustDIBuilderCreateUnionType(
DIB(cx),
containing_scope,
name.as_ptr(),
unknown_file_metadata(cx),
UNKNOWN_LINE_NUMBER,
union_size.bits(),
union_align.bits() as u32,
DIFlags::FlagZero,
Some(empty_array),
0, // RuntimeLang
unique_type_id.as_ptr())
};
metadata_stub
}
/// Creates debug information for the given global variable.
///
/// Adds the created metadata nodes directly to the crate's IR.
pub fn create_global_var_metadata(
cx: &CodegenCx<'ll, '_>,
def_id: DefId,
global: &'ll Value,
) {
if cx.dbg_cx.is_none() {
return;
}
let tcx = cx.tcx;
let attrs = tcx.codegen_fn_attrs(def_id);
if attrs.flags.contains(CodegenFnAttrFlags::NO_DEBUG) {
return;
}
let no_mangle = attrs.flags.contains(CodegenFnAttrFlags::NO_MANGLE);
// We may want to remove the namespace scope if we're in an extern block (see
// https://github.com/rust-lang/rust/pull/46457#issuecomment-351750952).
let var_scope = get_namespace_for_item(cx, def_id);
let span = tcx.def_span(def_id);
let (file_metadata, line_number) = if !span.is_dummy() {
let loc = span_start(cx, span);
(file_metadata(cx, &loc.file.name, LOCAL_CRATE), loc.line as c_uint)
} else {
(unknown_file_metadata(cx), UNKNOWN_LINE_NUMBER)
};
let is_local_to_unit = is_node_local_to_unit(cx, def_id);
let variable_type = Instance::mono(cx.tcx, def_id).ty(cx.tcx);
let type_metadata = type_metadata(cx, variable_type, span);
let var_name = SmallCStr::new(&tcx.item_name(def_id).as_str());
let linkage_name = if no_mangle {
None
} else {
let linkage_name = mangled_name_of_instance(cx, Instance::mono(tcx, def_id));
Some(SmallCStr::new(&linkage_name.name.as_str()))
};
let global_align = cx.align_of(variable_type);
unsafe {
llvm::LLVMRustDIBuilderCreateStaticVariable(DIB(cx),
Some(var_scope),
var_name.as_ptr(),
// If null, linkage_name field is omitted,
// which is what we want for no_mangle statics
linkage_name.as_ref()
.map_or(ptr::null(), |name| name.as_ptr()),
file_metadata,
line_number,
type_metadata,
is_local_to_unit,
global,
None,
global_align.bytes() as u32,
);
}
}
/// Creates debug information for the given vtable, which is for the
/// given type.
///
/// Adds the created metadata nodes directly to the crate's IR.
pub fn create_vtable_metadata(cx: &CodegenCx<'ll, 'tcx>, ty: Ty<'tcx>, vtable: &'ll Value) {
if cx.dbg_cx.is_none() {
return;
}
let type_metadata = type_metadata(cx, ty, syntax_pos::DUMMY_SP);
unsafe {
// `LLVMRustDIBuilderCreateStructType()` wants an empty array. A null
// pointer will lead to hard to trace and debug LLVM assertions
// later on in `llvm/lib/IR/Value.cpp`.
let empty_array = create_DIArray(DIB(cx), &[]);
let name = const_cstr!("vtable");
// Create a new one each time. We don't want metadata caching
// here, because each vtable will refer to a unique containing
// type.
let vtable_type = llvm::LLVMRustDIBuilderCreateStructType(
DIB(cx),
NO_SCOPE_METADATA,
name.as_ptr(),
unknown_file_metadata(cx),
UNKNOWN_LINE_NUMBER,
Size::ZERO.bits(),
cx.tcx.data_layout.pointer_align.abi.bits() as u32,
DIFlags::FlagArtificial,
None,
empty_array,
0,
Some(type_metadata),
name.as_ptr()
);
llvm::LLVMRustDIBuilderCreateStaticVariable(DIB(cx),
NO_SCOPE_METADATA,
name.as_ptr(),
ptr::null(),
unknown_file_metadata(cx),
UNKNOWN_LINE_NUMBER,
vtable_type,
true,
vtable,
None,
0);
}
}
/// Creates an "extension" of an existing `DIScope` into another file.
pub fn extend_scope_to_file(
cx: &CodegenCx<'ll, '_>,
scope_metadata: &'ll DIScope,
file: &syntax_pos::SourceFile,
defining_crate: CrateNum,
) -> &'ll DILexicalBlock {
let file_metadata = file_metadata(cx, &file.name, defining_crate);
unsafe {
llvm::LLVMRustDIBuilderCreateLexicalBlockFile(
DIB(cx),
scope_metadata,
file_metadata)
}
}