Reduce MIR memory usage

This commit is contained in:
hkalbasi 2023-05-19 00:16:52 +03:30
parent cae9660a1d
commit 23ce228d54
6 changed files with 83 additions and 55 deletions

View File

@ -205,7 +205,7 @@ type PlaceElem = ProjectionElem<LocalId, Ty>;
#[derive(Debug, Clone, PartialEq, Eq, Hash)]
pub struct Place {
pub local: LocalId,
pub projection: Vec<PlaceElem>,
pub projection: Box<[PlaceElem]>,
}
impl Place {
@ -216,13 +216,20 @@ impl Place {
fn iterate_over_parents(&self) -> impl Iterator<Item = Place> + '_ {
(0..self.projection.len())
.map(|x| &self.projection[0..x])
.map(|x| Place { local: self.local, projection: x.to_vec() })
.map(|x| Place { local: self.local, projection: x.to_vec().into() })
}
fn project(&self, projection: PlaceElem) -> Place {
Place {
local: self.local,
projection: self.projection.iter().cloned().chain([projection]).collect(),
}
}
}
impl From<LocalId> for Place {
fn from(local: LocalId) -> Self {
Self { local, projection: vec![] }
Self { local, projection: vec![].into() }
}
}
@ -437,7 +444,7 @@ pub enum TerminatorKind {
/// These are owned by the callee, which is free to modify them.
/// This allows the memory occupied by "by-value" arguments to be
/// reused across function calls without duplicating the contents.
args: Vec<Operand>,
args: Box<[Operand]>,
/// Where the returned value will be written
destination: Place,
/// Where to go after this call returns. If none, the call necessarily diverges.
@ -894,7 +901,7 @@ pub enum Rvalue {
///
/// Disallowed after deaggregation for all aggregate kinds except `Array` and `Generator`. After
/// generator lowering, `Generator` aggregate kinds are disallowed too.
Aggregate(AggregateKind, Vec<Operand>),
Aggregate(AggregateKind, Box<[Operand]>),
/// Transmutes a `*mut u8` into shallow-initialized `Box<T>`.
///
@ -1011,7 +1018,7 @@ impl MirBody {
for_operand(o2, &mut f);
}
Rvalue::Aggregate(_, ops) => {
for op in ops {
for op in ops.iter_mut() {
for_operand(op, &mut f);
}
}
@ -1058,6 +1065,27 @@ impl MirBody {
}
}
}
fn shrink_to_fit(&mut self) {
let MirBody {
basic_blocks,
locals,
start_block: _,
owner: _,
binding_locals,
param_locals,
closures,
} = self;
basic_blocks.shrink_to_fit();
locals.shrink_to_fit();
binding_locals.shrink_to_fit();
param_locals.shrink_to_fit();
closures.shrink_to_fit();
for (_, b) in basic_blocks.iter_mut() {
let BasicBlock { statements, terminator: _, is_cleanup: _ } = b;
statements.shrink_to_fit();
}
}
}
#[derive(Debug, PartialEq, Eq, Clone, Copy)]

View File

@ -93,7 +93,7 @@ fn moved_out_of_ref(db: &dyn HirDatabase, body: &MirBody) -> Vec<MovedOutOfRef>
Operand::Copy(p) | Operand::Move(p) => {
let mut ty: Ty = body.locals[p.local].ty.clone();
let mut is_dereference_of_ref = false;
for proj in &p.projection {
for proj in &*p.projection {
if *proj == ProjectionElem::Deref && ty.as_reference().is_some() {
is_dereference_of_ref = true;
}
@ -143,7 +143,7 @@ fn moved_out_of_ref(db: &dyn HirDatabase, body: &MirBody) -> Vec<MovedOutOfRef>
for_operand(o2, statement.span);
}
Rvalue::Aggregate(_, ops) => {
for op in ops {
for op in ops.iter() {
for_operand(op, statement.span);
}
}

View File

@ -562,7 +562,7 @@ impl Evaluator<'_> {
let mut ty: Ty =
self.ty_filler(&locals.body.locals[p.local].ty, locals.subst, locals.body.owner)?;
let mut metadata: Option<IntervalOrOwned> = None; // locals are always sized
for proj in &p.projection {
for proj in &*p.projection {
let prev_ty = ty.clone();
ty = proj.projected_ty(
ty,

View File

@ -387,7 +387,7 @@ impl<'ctx> MirLowerCtx<'ctx> {
current,
place,
ty,
vec![],
Box::new([]),
expr_id.into(),
)?;
}
@ -561,7 +561,7 @@ impl<'ctx> MirLowerCtx<'ctx> {
};
self.push_assignment(current, ref_mut_iterator_place.clone(), Rvalue::Ref(BorrowKind::Mut { allow_two_phase_borrow: false }, iterator_place), expr_id.into());
self.lower_loop(current, place, label, expr_id.into(), |this, begin| {
let Some(current) = this.lower_call(iter_next_fn_op, vec![Operand::Copy(ref_mut_iterator_place)], option_item_place.clone(), begin, false, expr_id.into())?
let Some(current) = this.lower_call(iter_next_fn_op, Box::new([Operand::Copy(ref_mut_iterator_place)]), option_item_place.clone(), begin, false, expr_id.into())?
else {
return Ok(());
};
@ -758,8 +758,7 @@ impl<'ctx> MirLowerCtx<'ctx> {
match x {
Some(x) => x,
None => {
let mut p = sp.clone();
p.projection.push(ProjectionElem::Field(FieldId {
let p = sp.project(ProjectionElem::Field(FieldId {
parent: variant_id,
local_id: LocalFieldId::from_raw(RawIdx::from(i as u32)),
}));
@ -782,10 +781,7 @@ impl<'ctx> MirLowerCtx<'ctx> {
};
let local_id =
variant_data.field(name).ok_or(MirLowerError::UnresolvedField)?;
let mut place = place;
place
.projection
.push(PlaceElem::Field(FieldId { parent: union_id.into(), local_id }));
let place = place.project(PlaceElem::Field(FieldId { parent: union_id.into(), local_id }));
self.lower_expr_to_place(*expr, place, current)
}
}
@ -826,8 +822,7 @@ impl<'ctx> MirLowerCtx<'ctx> {
let Some((operand, current)) = self.lower_expr_to_some_operand(*expr, current)? else {
return Ok(None);
};
let mut p = place;
p.projection.push(ProjectionElem::Deref);
let p = place.project(ProjectionElem::Deref);
self.push_assignment(current, p, operand.into(), expr_id.into());
Ok(Some(current))
},
@ -1031,7 +1026,7 @@ impl<'ctx> MirLowerCtx<'ctx> {
self.push_assignment(
current,
place,
Rvalue::Aggregate(AggregateKind::Closure(ty), operands),
Rvalue::Aggregate(AggregateKind::Closure(ty), operands.into()),
expr_id.into(),
);
Ok(Some(current))
@ -1128,11 +1123,11 @@ impl<'ctx> MirLowerCtx<'ctx> {
let index = name
.as_tuple_index()
.ok_or(MirLowerError::TypeError("named field on tuple"))?;
place.projection.push(ProjectionElem::TupleOrClosureField(index))
*place = place.project(ProjectionElem::TupleOrClosureField(index))
} else {
let field =
self.infer.field_resolution(expr_id).ok_or(MirLowerError::UnresolvedField)?;
place.projection.push(ProjectionElem::Field(field));
*place = place.project(ProjectionElem::Field(field));
}
} else {
not_supported!("")
@ -1242,7 +1237,7 @@ impl<'ctx> MirLowerCtx<'ctx> {
prev_block: BasicBlockId,
place: Place,
ty: Ty,
fields: Vec<Operand>,
fields: Box<[Operand]>,
span: MirSpan,
) -> Result<BasicBlockId> {
let subst = match ty.kind(Interner) {
@ -1280,13 +1275,13 @@ impl<'ctx> MirLowerCtx<'ctx> {
else {
return Ok(None);
};
self.lower_call(func, args, place, current, is_uninhabited, span)
self.lower_call(func, args.into(), place, current, is_uninhabited, span)
}
fn lower_call(
&mut self,
func: Operand,
args: Vec<Operand>,
args: Box<[Operand]>,
place: Place,
current: BasicBlockId,
is_uninhabited: bool,
@ -1744,12 +1739,13 @@ pub fn mir_body_for_closure_query(
match r {
Some(x) => {
p.local = closure_local;
let prev_projs =
mem::replace(&mut p.projection, vec![PlaceElem::TupleOrClosureField(x.1)]);
let mut next_projs = vec![PlaceElem::TupleOrClosureField(x.1)];
let prev_projs = mem::take(&mut p.projection);
if x.0.kind != CaptureKind::ByValue {
p.projection.push(ProjectionElem::Deref);
next_projs.push(ProjectionElem::Deref);
}
p.projection.extend(prev_projs.into_iter().skip(x.0.place.projections.len()));
next_projs.extend(prev_projs.iter().cloned().skip(x.0.place.projections.len()));
p.projection = next_projs.into();
}
None => err = Some(p.clone()),
}
@ -1764,6 +1760,7 @@ pub fn mir_body_for_closure_query(
if let Some(err) = err {
return Err(MirLowerError::UnresolvedUpvar(err));
}
ctx.result.shrink_to_fit();
Ok(Arc::new(ctx.result))
}
@ -1780,7 +1777,8 @@ pub fn mir_body_query(db: &dyn HirDatabase, def: DefWithBodyId) -> Result<Arc<Mi
});
let body = db.body(def);
let infer = db.infer(def);
let result = lower_to_mir(db, def, &body, &infer, body.body_expr)?;
let mut result = lower_to_mir(db, def, &body, &infer, body.body_expr)?;
result.shrink_to_fit();
Ok(Arc::new(result))
}

View File

@ -65,7 +65,7 @@ impl MirLowerCtx<'_> {
)? else {
return Ok(None);
};
x.0.projection.push(ProjectionElem::Deref);
x.0 = x.0.project(ProjectionElem::Deref);
Ok(Some(x))
}
Adjust::Deref(Some(od)) => {
@ -139,15 +139,14 @@ impl MirLowerCtx<'_> {
let ty = self.expr_ty_without_adjust(expr_id);
let ref_ty =
TyKind::Ref(Mutability::Not, static_lifetime(), ty).intern(Interner);
let mut temp: Place = self.temp(ref_ty, current, expr_id.into())?.into();
let temp: Place = self.temp(ref_ty, current, expr_id.into())?.into();
self.push_assignment(
current,
temp.clone(),
Operand::Static(s).into(),
expr_id.into(),
);
temp.projection.push(ProjectionElem::Deref);
Ok(Some((temp, current)))
Ok(Some((temp.project(ProjectionElem::Deref), current)))
}
_ => try_rvalue(self),
}
@ -196,7 +195,7 @@ impl MirLowerCtx<'_> {
let Some((mut r, current)) = self.lower_expr_as_place(current, *expr, true)? else {
return Ok(None);
};
r.projection.push(ProjectionElem::Deref);
r = r.project(ProjectionElem::Deref);
Ok(Some((r, current)))
}
_ => try_rvalue(self),
@ -253,7 +252,7 @@ impl MirLowerCtx<'_> {
let Some(current) = self.lower_expr_to_place(*index, l_index.into(), current)? else {
return Ok(None);
};
p_base.projection.push(ProjectionElem::Index(l_index));
p_base = p_base.project(ProjectionElem::Index(l_index));
Ok(Some((p_base, current)))
}
_ => try_rvalue(self),
@ -283,10 +282,10 @@ impl MirLowerCtx<'_> {
)
.intern(Interner),
);
let Some(current) = self.lower_call(index_fn_op, vec![Operand::Copy(place), index_operand], result.clone(), current, false, span)? else {
let Some(current) = self.lower_call(index_fn_op, Box::new([Operand::Copy(place), index_operand]), result.clone(), current, false, span)? else {
return Ok(None);
};
result.projection.push(ProjectionElem::Deref);
result = result.project(ProjectionElem::Deref);
Ok(Some((result, current)))
}
@ -330,10 +329,10 @@ impl MirLowerCtx<'_> {
.intern(Interner),
);
let mut result: Place = self.temp(target_ty_ref, current, span)?.into();
let Some(current) = self.lower_call(deref_fn_op, vec![Operand::Copy(ref_place)], result.clone(), current, false, span)? else {
let Some(current) = self.lower_call(deref_fn_op, Box::new([Operand::Copy(ref_place)]), result.clone(), current, false, span)? else {
return Ok(None);
};
result.projection.push(ProjectionElem::Deref);
result = result.project(ProjectionElem::Deref);
Ok(Some((result, current)))
}
}

View File

@ -110,10 +110,10 @@ impl MirLowerCtx<'_> {
Pat::Slice { prefix, slice, suffix } => {
pattern_matching_dereference(&mut cond_ty, &mut binding_mode, &mut cond_place);
for (i, &pat) in prefix.iter().enumerate() {
let mut next_place = cond_place.clone();
next_place
.projection
.push(ProjectionElem::ConstantIndex { offset: i as u64, from_end: false });
let next_place = cond_place.project(ProjectionElem::ConstantIndex {
offset: i as u64,
from_end: false,
});
let cond_ty = self.infer[pat].clone();
(current, current_else) = self.pattern_match(
current,
@ -126,8 +126,7 @@ impl MirLowerCtx<'_> {
}
if let Some(slice) = slice {
if let Pat::Bind { id, subpat: _ } = self.body[*slice] {
let mut next_place = cond_place.clone();
next_place.projection.push(ProjectionElem::Subslice {
let next_place = cond_place.project(ProjectionElem::Subslice {
from: prefix.len() as u64,
to: suffix.len() as u64,
});
@ -142,10 +141,10 @@ impl MirLowerCtx<'_> {
}
}
for (i, &pat) in suffix.iter().enumerate() {
let mut next_place = cond_place.clone();
next_place
.projection
.push(ProjectionElem::ConstantIndex { offset: i as u64, from_end: true });
let next_place = cond_place.project(ProjectionElem::ConstantIndex {
offset: i as u64,
from_end: true,
});
let cond_ty = self.infer[pat].clone();
(current, current_else) = self.pattern_match(
current,
@ -269,11 +268,10 @@ impl MirLowerCtx<'_> {
Pat::Ref { pat, mutability: _ } => {
if let Some((ty, _, _)) = cond_ty.as_reference() {
cond_ty = ty.clone();
cond_place.projection.push(ProjectionElem::Deref);
self.pattern_match(
current,
current_else,
cond_place,
cond_place.project(ProjectionElem::Deref),
cond_ty,
*pat,
binding_mode,
@ -479,8 +477,7 @@ impl MirLowerCtx<'_> {
binding_mode: BindingAnnotation,
) -> Result<(BasicBlockId, Option<BasicBlockId>)> {
for (proj, arg, ty) in args {
let mut cond_place = cond_place.clone();
cond_place.projection.push(proj);
let cond_place = cond_place.project(proj);
(current, current_else) =
self.pattern_match(current, current_else, cond_place, ty, arg, binding_mode)?;
}
@ -513,5 +510,11 @@ fn pattern_matching_dereference(
cond_place: &mut Place,
) {
let cnt = pattern_matching_dereference_count(cond_ty, binding_mode);
cond_place.projection.extend((0..cnt).map(|_| ProjectionElem::Deref));
cond_place.projection = cond_place
.projection
.iter()
.cloned()
.chain((0..cnt).map(|_| ProjectionElem::Deref))
.collect::<Vec<_>>()
.into();
}