bjoernager/rust
bjoernager/rust
1
Fork 0
Code Activity

Refactor how MIR represents composite debuginfo.

Browse source
This commit is contained in:
Camille GILLOT 2023-08-26 16:58:42 +00:00
parent 429a9258f1
commit 26c48e6f95
17 changed files with 223 additions and 244 deletions
Download patch file Download diff file Expand all files Collapse all files

70
compiler/rustc_middle/src/mir/mod.rs
View file

@ -1028,19 +1028,6 @@ pub enum VarDebugInfoContents<'tcx> {
/// This `Place` only contains projection which satisfy `can_use_in_debuginfo`.
Place(Place<'tcx>),
Const(Constant<'tcx>),
/// The user variable's data is split across several fragments,
/// each described by a `VarDebugInfoFragment`.
/// See DWARF 5's "2.6.1.2 Composite Location Descriptions"
/// and LLVM's `DW_OP_LLVM_fragment` for more details on
/// the underlying debuginfo feature this relies on.
Composite {
/// Type of the original user variable.
/// This cannot contain a union or an enum.
ty: Ty<'tcx>,
/// All the parts of the original user variable, which ended
/// up in disjoint places, due to optimizations.
fragments: Vec<VarDebugInfoFragment<'tcx>>,
},
}
impl<'tcx> Debug for VarDebugInfoContents<'tcx> {
@ -1048,19 +1035,16 @@ impl<'tcx> Debug for VarDebugInfoContents<'tcx> {
match self {
VarDebugInfoContents::Const(c) => write!(fmt, "{c}"),
VarDebugInfoContents::Place(p) => write!(fmt, "{p:?}"),
VarDebugInfoContents::Composite { ty, fragments } => {
write!(fmt, "{ty:?}{{ ")?;
for f in fragments.iter() {
write!(fmt, "{f:?}, ")?;
}
write!(fmt, "}}")
}
}
}
}
#[derive(Clone, TyEncodable, TyDecodable, HashStable, TypeFoldable, TypeVisitable)]
#[derive(Clone, Debug, TyEncodable, TyDecodable, HashStable, TypeFoldable, TypeVisitable)]
pub struct VarDebugInfoFragment<'tcx> {
/// Type of the original user variable.
/// This cannot contain a union or an enum.
pub ty: Ty<'tcx>,
/// Where in the composite user variable this fragment is,
/// represented as a "projection" into the composite variable.
/// At lower levels, this corresponds to a byte/bit range.
@ -1071,29 +1055,10 @@ pub struct VarDebugInfoFragment<'tcx> {
// to match on the discriminant, or by using custom type debuginfo
// with non-overlapping variants for the composite variable.
pub projection: Vec<PlaceElem<'tcx>>,
/// Where the data for this fragment can be found.
/// This `Place` only contains projection which satisfy `can_use_in_debuginfo`.
pub contents: Place<'tcx>,
}
impl Debug for VarDebugInfoFragment<'_> {
fn fmt(&self, fmt: &mut Formatter<'_>) -> fmt::Result {
for elem in self.projection.iter() {
match elem {
ProjectionElem::Field(field, _) => {
write!(fmt, ".{:?}", field.index())?;
}
_ => bug!("unsupported fragment projection `{:?}`", elem),
}
}
write!(fmt, " => {:?}", self.contents)
}
}
/// Debug information pertaining to a user variable.
#[derive(Clone, Debug, TyEncodable, TyDecodable, HashStable, TypeFoldable, TypeVisitable)]
#[derive(Clone, TyEncodable, TyDecodable, HashStable, TypeFoldable, TypeVisitable)]
pub struct VarDebugInfo<'tcx> {
pub name: Symbol,
@ -1102,6 +1067,13 @@ pub struct VarDebugInfo<'tcx> {
/// (see `LocalDecl`'s `source_info` field for more details).
pub source_info: SourceInfo,
/// The user variable's data is split across several fragments,
/// each described by a `VarDebugInfoFragment`.
/// See DWARF 5's "2.6.1.2 Composite Location Descriptions"
/// and LLVM's `DW_OP_LLVM_fragment` for more details on
/// the underlying debuginfo feature this relies on.
pub composite: Option<Box<VarDebugInfoFragment<'tcx>>>,
/// Where the data for this user variable is to be found.
pub value: VarDebugInfoContents<'tcx>,
@ -1111,6 +1083,20 @@ pub struct VarDebugInfo<'tcx> {
pub argument_index: Option<u16>,
}
impl Debug for VarDebugInfo<'_> {
fn fmt(&self, fmt: &mut Formatter<'_>) -> fmt::Result {
if let Some(box VarDebugInfoFragment { ty, ref projection }) = self.composite {
pre_fmt_projection(&projection[..], fmt)?;
write!(fmt, "({}: {})", self.name, ty)?;
post_fmt_projection(&projection[..], fmt)?;
} else {
write!(fmt, "{}", self.name)?;
}
write!(fmt, " => {:?}", self.value)
}
}
///////////////////////////////////////////////////////////////////////////
// BasicBlock
@ -3070,6 +3056,6 @@ mod size_asserts {
static_assert_size!(StatementKind<'_>, 16);
static_assert_size!(Terminator<'_>, 104);
static_assert_size!(TerminatorKind<'_>, 88);
static_assert_size!(VarDebugInfo<'_>, 80);
static_assert_size!(VarDebugInfo<'_>, 88);
// tidy-alphabetical-end
}

5
compiler/rustc_middle/src/mir/pretty.rs
View file

@ -554,10 +554,7 @@ fn write_scope_tree(
continue;
}
let indented_debug_info = format!(
"{0:1$}debug {2} => {3:?};",
INDENT, indent, var_debug_info.name, var_debug_info.value,
);
let indented_debug_info = format!("{0:1$}debug {2:?};", INDENT, indent, var_debug_info);
if tcx.sess.opts.unstable_opts.mir_include_spans {
writeln!(

19
compiler/rustc_middle/src/mir/visit.rs
View file

@ -838,12 +838,20 @@ macro_rules! make_mir_visitor {
let VarDebugInfo {
name: _,
source_info,
composite,
value,
argument_index: _,
} = var_debug_info;
self.visit_source_info(source_info);
let location = Location::START;
if let Some(box VarDebugInfoFragment { ref $($mutability)? ty, ref $($mutability)? projection }) = composite {
self.visit_ty($(& $mutability)? *ty, TyContext::Location(location));
for elem in projection {
let ProjectionElem::Field(_, ty) = elem else { bug!() };
self.visit_ty($(& $mutability)? *ty, TyContext::Location(location));
}
}
match value {
VarDebugInfoContents::Const(c) => self.visit_constant(c, location),
VarDebugInfoContents::Place(place) =>
@ -852,17 +860,6 @@ macro_rules! make_mir_visitor {
PlaceContext::NonUse(NonUseContext::VarDebugInfo),
location
),
VarDebugInfoContents::Composite { ty, fragments } => {
// FIXME(eddyb) use a better `TyContext` here.
self.visit_ty($(& $mutability)? *ty, TyContext::Location(location));
for VarDebugInfoFragment { projection: _, contents } in fragments {
self.visit_place(
contents,
PlaceContext::NonUse(NonUseContext::VarDebugInfo),
location,
);
}
}
}
}