rust/compiler/rustc_passes/src/hir_stats.rs
2022-09-12 13:24:27 +10:00

695 lines
22 KiB
Rust

// The visitors in this module collect sizes and counts of the most important
// pieces of AST and HIR. The resulting numbers are good approximations but not
// completely accurate (some things might be counted twice, others missed).
use rustc_ast::visit as ast_visit;
use rustc_ast::visit::BoundKind;
use rustc_ast::{self as ast, AttrId, NodeId};
use rustc_data_structures::fx::{FxHashMap, FxHashSet};
use rustc_hir as hir;
use rustc_hir::intravisit as hir_visit;
use rustc_hir::HirId;
use rustc_middle::hir::map::Map;
use rustc_middle::ty::TyCtxt;
use rustc_middle::util::common::to_readable_str;
use rustc_span::Span;
#[derive(Copy, Clone, PartialEq, Eq, Hash)]
enum Id {
Node(HirId),
Attr(AttrId),
None,
}
struct NodeStats {
count: usize,
size: usize,
}
impl NodeStats {
fn new() -> NodeStats {
NodeStats { count: 0, size: 0 }
}
}
struct Node {
stats: NodeStats,
subnodes: FxHashMap<&'static str, NodeStats>,
}
impl Node {
fn new() -> Node {
Node { stats: NodeStats::new(), subnodes: FxHashMap::default() }
}
}
/// This type measures the size of AST and HIR nodes, by implementing the AST
/// and HIR `Visitor` traits. But we don't measure every visited type because
/// that could cause double counting.
///
/// For example, `ast::Visitor` has `visit_ident`, but `Ident`s are always
/// stored inline within other AST nodes, so we don't implement `visit_ident`
/// here. In contrast, we do implement `visit_expr` because `ast::Expr` is
/// always stored as `P<ast::Expr>`, and every such expression should be
/// measured separately.
///
/// In general, a `visit_foo` method should be implemented here if the
/// corresponding `Foo` type is always stored on its own, e.g.: `P<Foo>`,
/// `Box<Foo>`, `Vec<Foo>`, `Box<[Foo]>`.
///
/// There are some types in the AST and HIR tree that the visitors do not have
/// a `visit_*` method for, and so we cannot measure these, which is
/// unfortunate.
struct StatCollector<'k> {
krate: Option<Map<'k>>,
nodes: FxHashMap<&'static str, Node>,
seen: FxHashSet<Id>,
}
pub fn print_hir_stats(tcx: TyCtxt<'_>) {
let mut collector = StatCollector {
krate: Some(tcx.hir()),
nodes: FxHashMap::default(),
seen: FxHashSet::default(),
};
tcx.hir().walk_toplevel_module(&mut collector);
tcx.hir().walk_attributes(&mut collector);
collector.print("HIR STATS", "hir-stats");
}
pub fn print_ast_stats(krate: &ast::Crate, title: &str, prefix: &str) {
use rustc_ast::visit::Visitor;
let mut collector =
StatCollector { krate: None, nodes: FxHashMap::default(), seen: FxHashSet::default() };
collector.visit_crate(krate);
collector.print(title, prefix);
}
impl<'k> StatCollector<'k> {
// Record a top-level node.
fn record<T>(&mut self, label: &'static str, id: Id, val: &T) {
self.record_inner(label, None, id, val);
}
// Record a two-level entry, with a top-level enum type and a variant.
fn record_variant<T>(&mut self, label1: &'static str, label2: &'static str, id: Id, val: &T) {
self.record_inner(label1, Some(label2), id, val);
}
fn record_inner<T>(
&mut self,
label1: &'static str,
label2: Option<&'static str>,
id: Id,
val: &T,
) {
if id != Id::None && !self.seen.insert(id) {
return;
}
let node = self.nodes.entry(label1).or_insert(Node::new());
node.stats.count += 1;
node.stats.size = std::mem::size_of_val(val);
if let Some(label2) = label2 {
let subnode = node.subnodes.entry(label2).or_insert(NodeStats::new());
subnode.count += 1;
subnode.size = std::mem::size_of_val(val);
}
}
fn print(&self, title: &str, prefix: &str) {
let mut nodes: Vec<_> = self.nodes.iter().collect();
nodes.sort_by_key(|&(_, ref node)| node.stats.count * node.stats.size);
let total_size = nodes.iter().map(|(_, node)| node.stats.count * node.stats.size).sum();
eprintln!("{} {}", prefix, title);
eprintln!(
"{} {:<18}{:>18}{:>14}{:>14}",
prefix, "Name", "Accumulated Size", "Count", "Item Size"
);
eprintln!("{} ----------------------------------------------------------------", prefix);
let percent = |m, n| (m * 100) as f64 / n as f64;
for (label, node) in nodes {
let size = node.stats.count * node.stats.size;
eprintln!(
"{} {:<18}{:>10} ({:4.1}%){:>14}{:>14}",
prefix,
label,
to_readable_str(size),
percent(size, total_size),
to_readable_str(node.stats.count),
to_readable_str(node.stats.size)
);
if !node.subnodes.is_empty() {
let mut subnodes: Vec<_> = node.subnodes.iter().collect();
subnodes.sort_by_key(|&(_, ref subnode)| subnode.count * subnode.size);
for (label, subnode) in subnodes {
let size = subnode.count * subnode.size;
eprintln!(
"{} - {:<18}{:>10} ({:4.1}%){:>14}",
prefix,
label,
to_readable_str(size),
percent(size, total_size),
to_readable_str(subnode.count),
);
}
}
}
eprintln!("{} ----------------------------------------------------------------", prefix);
eprintln!("{} {:<18}{:>10}", prefix, "Total", to_readable_str(total_size));
eprintln!("{}", prefix);
}
}
// Used to avoid boilerplate for types with many variants.
macro_rules! record_variants {
(
($self:ident, $val:expr, $kind:expr, $id:expr, $mod:ident, $ty:ty, $tykind:ident),
[$($variant:ident),*]
) => {
match $kind {
$(
$mod::$tykind::$variant { .. } => {
$self.record_variant(stringify!($ty), stringify!($variant), $id, $val)
}
)*
}
};
}
impl<'v> hir_visit::Visitor<'v> for StatCollector<'v> {
fn visit_param(&mut self, param: &'v hir::Param<'v>) {
self.record("Param", Id::Node(param.hir_id), param);
hir_visit::walk_param(self, param)
}
fn visit_nested_item(&mut self, id: hir::ItemId) {
let nested_item = self.krate.unwrap().item(id);
self.visit_item(nested_item)
}
fn visit_nested_trait_item(&mut self, trait_item_id: hir::TraitItemId) {
let nested_trait_item = self.krate.unwrap().trait_item(trait_item_id);
self.visit_trait_item(nested_trait_item)
}
fn visit_nested_impl_item(&mut self, impl_item_id: hir::ImplItemId) {
let nested_impl_item = self.krate.unwrap().impl_item(impl_item_id);
self.visit_impl_item(nested_impl_item)
}
fn visit_nested_foreign_item(&mut self, id: hir::ForeignItemId) {
let nested_foreign_item = self.krate.unwrap().foreign_item(id);
self.visit_foreign_item(nested_foreign_item);
}
fn visit_nested_body(&mut self, body_id: hir::BodyId) {
let nested_body = self.krate.unwrap().body(body_id);
self.visit_body(nested_body)
}
fn visit_item(&mut self, i: &'v hir::Item<'v>) {
record_variants!(
(self, i, i.kind, Id::Node(i.hir_id()), hir, Item, ItemKind),
[
ExternCrate,
Use,
Static,
Const,
Fn,
Macro,
Mod,
ForeignMod,
GlobalAsm,
TyAlias,
OpaqueTy,
Enum,
Struct,
Union,
Trait,
TraitAlias,
Impl
]
);
hir_visit::walk_item(self, i)
}
fn visit_body(&mut self, b: &'v hir::Body<'v>) {
self.record("Body", Id::None, b);
hir_visit::walk_body(self, b);
}
fn visit_mod(&mut self, m: &'v hir::Mod<'v>, _s: Span, n: HirId) {
self.record("Mod", Id::None, m);
hir_visit::walk_mod(self, m, n)
}
fn visit_foreign_item(&mut self, i: &'v hir::ForeignItem<'v>) {
record_variants!(
(self, i, i.kind, Id::Node(i.hir_id()), hir, ForeignItem, ForeignItemKind),
[Fn, Static, Type]
);
hir_visit::walk_foreign_item(self, i)
}
fn visit_local(&mut self, l: &'v hir::Local<'v>) {
self.record("Local", Id::Node(l.hir_id), l);
hir_visit::walk_local(self, l)
}
fn visit_block(&mut self, b: &'v hir::Block<'v>) {
self.record("Block", Id::Node(b.hir_id), b);
hir_visit::walk_block(self, b)
}
fn visit_stmt(&mut self, s: &'v hir::Stmt<'v>) {
record_variants!(
(self, s, s.kind, Id::Node(s.hir_id), hir, Stmt, StmtKind),
[Local, Item, Expr, Semi]
);
hir_visit::walk_stmt(self, s)
}
fn visit_arm(&mut self, a: &'v hir::Arm<'v>) {
self.record("Arm", Id::Node(a.hir_id), a);
hir_visit::walk_arm(self, a)
}
fn visit_pat(&mut self, p: &'v hir::Pat<'v>) {
record_variants!(
(self, p, p.kind, Id::Node(p.hir_id), hir, Pat, PatKind),
[Wild, Binding, Struct, TupleStruct, Or, Path, Tuple, Box, Ref, Lit, Range, Slice]
);
hir_visit::walk_pat(self, p)
}
fn visit_pat_field(&mut self, f: &'v hir::PatField<'v>) {
self.record("PatField", Id::Node(f.hir_id), f);
hir_visit::walk_pat_field(self, f)
}
fn visit_expr(&mut self, e: &'v hir::Expr<'v>) {
record_variants!(
(self, e, e.kind, Id::Node(e.hir_id), hir, Expr, ExprKind),
[
Box, ConstBlock, Array, Call, MethodCall, Tup, Binary, Unary, Lit, Cast, Type,
DropTemps, Let, If, Loop, Match, Closure, Block, Assign, AssignOp, Field, Index,
Path, AddrOf, Break, Continue, Ret, InlineAsm, Struct, Repeat, Yield, Err
]
);
hir_visit::walk_expr(self, e)
}
fn visit_let_expr(&mut self, lex: &'v hir::Let<'v>) {
self.record("Let", Id::Node(lex.hir_id), lex);
hir_visit::walk_let_expr(self, lex)
}
fn visit_expr_field(&mut self, f: &'v hir::ExprField<'v>) {
self.record("ExprField", Id::Node(f.hir_id), f);
hir_visit::walk_expr_field(self, f)
}
fn visit_ty(&mut self, t: &'v hir::Ty<'v>) {
record_variants!(
(self, t, t.kind, Id::Node(t.hir_id), hir, Ty, TyKind),
[
Slice,
Array,
Ptr,
Rptr,
BareFn,
Never,
Tup,
Path,
OpaqueDef,
TraitObject,
Typeof,
Infer,
Err
]
);
hir_visit::walk_ty(self, t)
}
fn visit_generic_param(&mut self, p: &'v hir::GenericParam<'v>) {
self.record("GenericParam", Id::Node(p.hir_id), p);
hir_visit::walk_generic_param(self, p)
}
fn visit_generics(&mut self, g: &'v hir::Generics<'v>) {
self.record("Generics", Id::None, g);
hir_visit::walk_generics(self, g)
}
fn visit_where_predicate(&mut self, p: &'v hir::WherePredicate<'v>) {
record_variants!(
(self, p, p, Id::None, hir, WherePredicate, WherePredicate),
[BoundPredicate, RegionPredicate, EqPredicate]
);
hir_visit::walk_where_predicate(self, p)
}
fn visit_fn(
&mut self,
fk: hir_visit::FnKind<'v>,
fd: &'v hir::FnDecl<'v>,
b: hir::BodyId,
_: Span,
id: hir::HirId,
) {
self.record("FnDecl", Id::None, fd);
hir_visit::walk_fn(self, fk, fd, b, id)
}
fn visit_use(&mut self, p: &'v hir::Path<'v>, hir_id: hir::HirId) {
// This is `visit_use`, but the type is `Path` so record it that way.
self.record("Path", Id::None, p);
hir_visit::walk_use(self, p, hir_id)
}
fn visit_trait_item(&mut self, ti: &'v hir::TraitItem<'v>) {
record_variants!(
(self, ti, ti.kind, Id::Node(ti.hir_id()), hir, TraitItem, TraitItemKind),
[Const, Fn, Type]
);
hir_visit::walk_trait_item(self, ti)
}
fn visit_trait_item_ref(&mut self, ti: &'v hir::TraitItemRef) {
self.record("TraitItemRef", Id::Node(ti.id.hir_id()), ti);
hir_visit::walk_trait_item_ref(self, ti)
}
fn visit_impl_item(&mut self, ii: &'v hir::ImplItem<'v>) {
record_variants!(
(self, ii, ii.kind, Id::Node(ii.hir_id()), hir, ImplItem, ImplItemKind),
[Const, Fn, TyAlias]
);
hir_visit::walk_impl_item(self, ii)
}
fn visit_foreign_item_ref(&mut self, fi: &'v hir::ForeignItemRef) {
self.record("ForeignItemRef", Id::Node(fi.id.hir_id()), fi);
hir_visit::walk_foreign_item_ref(self, fi)
}
fn visit_impl_item_ref(&mut self, ii: &'v hir::ImplItemRef) {
self.record("ImplItemRef", Id::Node(ii.id.hir_id()), ii);
hir_visit::walk_impl_item_ref(self, ii)
}
fn visit_param_bound(&mut self, b: &'v hir::GenericBound<'v>) {
record_variants!(
(self, b, b, Id::None, hir, GenericBound, GenericBound),
[Trait, LangItemTrait, Outlives]
);
hir_visit::walk_param_bound(self, b)
}
fn visit_field_def(&mut self, s: &'v hir::FieldDef<'v>) {
self.record("FieldDef", Id::Node(s.hir_id), s);
hir_visit::walk_field_def(self, s)
}
fn visit_variant(&mut self, v: &'v hir::Variant<'v>) {
self.record("Variant", Id::None, v);
hir_visit::walk_variant(self, v)
}
fn visit_generic_arg(&mut self, ga: &'v hir::GenericArg<'v>) {
record_variants!(
(self, ga, ga, Id::Node(ga.hir_id()), hir, GenericArg, GenericArg),
[Lifetime, Type, Const, Infer]
);
match ga {
hir::GenericArg::Lifetime(lt) => self.visit_lifetime(lt),
hir::GenericArg::Type(ty) => self.visit_ty(ty),
hir::GenericArg::Const(ct) => self.visit_anon_const(&ct.value),
hir::GenericArg::Infer(inf) => self.visit_infer(inf),
}
}
fn visit_lifetime(&mut self, lifetime: &'v hir::Lifetime) {
self.record("Lifetime", Id::Node(lifetime.hir_id), lifetime);
hir_visit::walk_lifetime(self, lifetime)
}
fn visit_path(&mut self, path: &'v hir::Path<'v>, _id: hir::HirId) {
self.record("Path", Id::None, path);
hir_visit::walk_path(self, path)
}
fn visit_path_segment(&mut self, path_segment: &'v hir::PathSegment<'v>) {
self.record("PathSegment", Id::None, path_segment);
hir_visit::walk_path_segment(self, path_segment)
}
fn visit_generic_args(&mut self, ga: &'v hir::GenericArgs<'v>) {
self.record("GenericArgs", Id::None, ga);
hir_visit::walk_generic_args(self, ga)
}
fn visit_assoc_type_binding(&mut self, type_binding: &'v hir::TypeBinding<'v>) {
self.record("TypeBinding", Id::Node(type_binding.hir_id), type_binding);
hir_visit::walk_assoc_type_binding(self, type_binding)
}
fn visit_attribute(&mut self, attr: &'v ast::Attribute) {
self.record("Attribute", Id::Attr(attr.id), attr);
}
fn visit_inline_asm(&mut self, asm: &'v hir::InlineAsm<'v>, id: HirId) {
self.record("InlineAsm", Id::None, asm);
hir_visit::walk_inline_asm(self, asm, id);
}
}
impl<'v> ast_visit::Visitor<'v> for StatCollector<'v> {
fn visit_foreign_item(&mut self, i: &'v ast::ForeignItem) {
record_variants!(
(self, i, i.kind, Id::None, ast, ForeignItem, ForeignItemKind),
[Static, Fn, TyAlias, MacCall]
);
ast_visit::walk_foreign_item(self, i)
}
fn visit_item(&mut self, i: &'v ast::Item) {
record_variants!(
(self, i, i.kind, Id::None, ast, Item, ItemKind),
[
ExternCrate,
Use,
Static,
Const,
Fn,
Mod,
ForeignMod,
GlobalAsm,
TyAlias,
Enum,
Struct,
Union,
Trait,
TraitAlias,
Impl,
MacCall,
MacroDef
]
);
ast_visit::walk_item(self, i)
}
fn visit_local(&mut self, l: &'v ast::Local) {
self.record("Local", Id::None, l);
ast_visit::walk_local(self, l)
}
fn visit_block(&mut self, b: &'v ast::Block) {
self.record("Block", Id::None, b);
ast_visit::walk_block(self, b)
}
fn visit_stmt(&mut self, s: &'v ast::Stmt) {
record_variants!(
(self, s, s.kind, Id::None, ast, Stmt, StmtKind),
[Local, Item, Expr, Semi, Empty, MacCall]
);
ast_visit::walk_stmt(self, s)
}
fn visit_param(&mut self, p: &'v ast::Param) {
self.record("Param", Id::None, p);
ast_visit::walk_param(self, p)
}
fn visit_arm(&mut self, a: &'v ast::Arm) {
self.record("Arm", Id::None, a);
ast_visit::walk_arm(self, a)
}
fn visit_pat(&mut self, p: &'v ast::Pat) {
record_variants!(
(self, p, p.kind, Id::None, ast, Pat, PatKind),
[
Wild,
Ident,
Struct,
TupleStruct,
Or,
Path,
Tuple,
Box,
Ref,
Lit,
Range,
Slice,
Rest,
Paren,
MacCall
]
);
ast_visit::walk_pat(self, p)
}
fn visit_expr(&mut self, e: &'v ast::Expr) {
record_variants!(
(self, e, e.kind, Id::None, ast, Expr, ExprKind),
[
Box, Array, ConstBlock, Call, MethodCall, Tup, Binary, Unary, Lit, Cast, Type, Let,
If, While, ForLoop, Loop, Match, Closure, Block, Async, Await, TryBlock, Assign,
AssignOp, Field, Index, Range, Underscore, Path, AddrOf, Break, Continue, Ret,
InlineAsm, MacCall, Struct, Repeat, Paren, Try, Yield, Yeet, Err
]
);
ast_visit::walk_expr(self, e)
}
fn visit_ty(&mut self, t: &'v ast::Ty) {
record_variants!(
(self, t, t.kind, Id::None, ast, Ty, TyKind),
[
Slice,
Array,
Ptr,
Rptr,
BareFn,
Never,
Tup,
Path,
TraitObject,
ImplTrait,
Paren,
Typeof,
Infer,
ImplicitSelf,
MacCall,
Err,
CVarArgs
]
);
ast_visit::walk_ty(self, t)
}
fn visit_generic_param(&mut self, g: &'v ast::GenericParam) {
self.record("GenericParam", Id::None, g);
ast_visit::walk_generic_param(self, g)
}
fn visit_where_predicate(&mut self, p: &'v ast::WherePredicate) {
record_variants!(
(self, p, p, Id::None, ast, WherePredicate, WherePredicate),
[BoundPredicate, RegionPredicate, EqPredicate]
);
ast_visit::walk_where_predicate(self, p)
}
fn visit_fn(&mut self, fk: ast_visit::FnKind<'v>, _: Span, _: NodeId) {
self.record("FnDecl", Id::None, fk.decl());
ast_visit::walk_fn(self, fk)
}
fn visit_assoc_item(&mut self, i: &'v ast::AssocItem, ctxt: ast_visit::AssocCtxt) {
record_variants!(
(self, i, i.kind, Id::None, ast, AssocItem, AssocItemKind),
[Const, Fn, TyAlias, MacCall]
);
ast_visit::walk_assoc_item(self, i, ctxt);
}
fn visit_param_bound(&mut self, b: &'v ast::GenericBound, _ctxt: BoundKind) {
record_variants!(
(self, b, b, Id::None, ast, GenericBound, GenericBound),
[Trait, Outlives]
);
ast_visit::walk_param_bound(self, b)
}
fn visit_field_def(&mut self, s: &'v ast::FieldDef) {
self.record("FieldDef", Id::None, s);
ast_visit::walk_field_def(self, s)
}
fn visit_variant(&mut self, v: &'v ast::Variant) {
self.record("Variant", Id::None, v);
ast_visit::walk_variant(self, v)
}
// `UseTree` has one inline use (in `ast::ItemKind::Use`) and one
// non-inline use (in `ast::UseTreeKind::Nested). The former case is more
// common, so we don't implement `visit_use_tree` and tolerate the missed
// coverage in the latter case.
// `PathSegment` has one inline use (in `ast::ExprKind::MethodCall`) and
// one non-inline use (in `ast::Path::segments`). The latter case is more
// common than the former case, so we implement this visitor and tolerate
// the double counting in the former case.
fn visit_path_segment(&mut self, path_segment: &'v ast::PathSegment) {
self.record("PathSegment", Id::None, path_segment);
ast_visit::walk_path_segment(self, path_segment)
}
// `GenericArgs` has one inline use (in `ast::AssocConstraint::gen_args`) and one
// non-inline use (in `ast::PathSegment::args`). The latter case is more
// common, so we implement `visit_generic_args` and tolerate the double
// counting in the former case.
fn visit_generic_args(&mut self, g: &'v ast::GenericArgs) {
record_variants!(
(self, g, g, Id::None, ast, GenericArgs, GenericArgs),
[AngleBracketed, Parenthesized]
);
ast_visit::walk_generic_args(self, g)
}
fn visit_attribute(&mut self, attr: &'v ast::Attribute) {
record_variants!(
(self, attr, attr.kind, Id::None, ast, Attribute, AttrKind),
[Normal, DocComment]
);
ast_visit::walk_attribute(self, attr)
}
fn visit_expr_field(&mut self, f: &'v ast::ExprField) {
self.record("ExprField", Id::None, f);
ast_visit::walk_expr_field(self, f)
}
fn visit_crate(&mut self, krate: &'v ast::Crate) {
self.record("Crate", Id::None, krate);
ast_visit::walk_crate(self, krate)
}
fn visit_inline_asm(&mut self, asm: &'v ast::InlineAsm) {
self.record("InlineAsm", Id::None, asm);
ast_visit::walk_inline_asm(self, asm)
}
}