summaryrefslogtreecommitdiffstats
path: root/compiler/rustc_passes/src/liveness.rs
diff options
context:
space:
mode:
authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-18 02:49:50 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-18 02:49:50 +0000
commit9835e2ae736235810b4ea1c162ca5e65c547e770 (patch)
tree3fcebf40ed70e581d776a8a4c65923e8ec20e026 /compiler/rustc_passes/src/liveness.rs
parentReleasing progress-linux version 1.70.0+dfsg2-1~progress7.99u1. (diff)
downloadrustc-9835e2ae736235810b4ea1c162ca5e65c547e770.tar.xz
rustc-9835e2ae736235810b4ea1c162ca5e65c547e770.zip
Merging upstream version 1.71.1+dfsg1.
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'compiler/rustc_passes/src/liveness.rs')
-rw-r--r--compiler/rustc_passes/src/liveness.rs242
1 files changed, 101 insertions, 141 deletions
diff --git a/compiler/rustc_passes/src/liveness.rs b/compiler/rustc_passes/src/liveness.rs
index a8471ce3b..63b1578d4 100644
--- a/compiler/rustc_passes/src/liveness.rs
+++ b/compiler/rustc_passes/src/liveness.rs
@@ -81,23 +81,24 @@
//! We generate various special nodes for various, well, special purposes.
//! These are described in the `Liveness` struct.
+use crate::errors;
+
use self::LiveNodeKind::*;
use self::VarKind::*;
use rustc_ast::InlineAsmOptions;
use rustc_data_structures::fx::FxIndexMap;
-use rustc_errors::Applicability;
-use rustc_errors::Diagnostic;
use rustc_hir as hir;
use rustc_hir::def::*;
-use rustc_hir::def_id::{DefId, LocalDefId};
+use rustc_hir::def_id::LocalDefId;
use rustc_hir::intravisit::{self, Visitor};
use rustc_hir::{Expr, HirId, HirIdMap, HirIdSet};
-use rustc_index::vec::IndexVec;
-use rustc_middle::ty::query::Providers;
+use rustc_index::IndexVec;
+use rustc_middle::query::Providers;
use rustc_middle::ty::{self, RootVariableMinCaptureList, Ty, TyCtxt};
use rustc_session::lint;
use rustc_span::symbol::{kw, sym, Symbol};
+use rustc_span::DUMMY_SP;
use rustc_span::{BytePos, Span};
use std::collections::VecDeque;
@@ -137,14 +138,9 @@ fn live_node_kind_to_string(lnk: LiveNodeKind, tcx: TyCtxt<'_>) -> String {
}
}
-fn check_liveness(tcx: TyCtxt<'_>, def_id: DefId) {
- let local_def_id = match def_id.as_local() {
- None => return,
- Some(def_id) => def_id,
- };
-
+fn check_liveness(tcx: TyCtxt<'_>, def_id: LocalDefId) {
// Don't run unused pass for #[derive()]
- let parent = tcx.local_parent(local_def_id);
+ let parent = tcx.local_parent(def_id);
if let DefKind::Impl { .. } = tcx.def_kind(parent)
&& tcx.has_attr(parent, sym::automatically_derived)
{
@@ -152,12 +148,12 @@ fn check_liveness(tcx: TyCtxt<'_>, def_id: DefId) {
}
// Don't run unused pass for #[naked]
- if tcx.has_attr(def_id, sym::naked) {
+ if tcx.has_attr(def_id.to_def_id(), sym::naked) {
return;
}
let mut maps = IrMaps::new(tcx);
- let body_id = tcx.hir().body_owned_by(local_def_id);
+ let body_id = tcx.hir().body_owned_by(def_id);
let hir_id = tcx.hir().body_owner(body_id);
let body = tcx.hir().body(body_id);
@@ -173,7 +169,7 @@ fn check_liveness(tcx: TyCtxt<'_>, def_id: DefId) {
maps.visit_body(body);
// compute liveness
- let mut lsets = Liveness::new(&mut maps, local_def_id);
+ let mut lsets = Liveness::new(&mut maps, def_id);
let entry_ln = lsets.compute(&body, hir_id);
lsets.log_liveness(entry_ln, body_id.hir_id);
@@ -331,7 +327,7 @@ impl<'tcx> IrMaps<'tcx> {
pats.extend(inner_pat.iter());
}
Struct(_, fields, _) => {
- let (short, not_short): (Vec<_>, _) =
+ let (short, not_short): (Vec<hir::PatField<'_>>, _) =
fields.iter().partition(|f| f.is_shorthand);
shorthand_field_ids.extend(short.iter().map(|f| f.pat.hir_id));
pats.extend(not_short.iter().map(|f| f.pat));
@@ -473,6 +469,7 @@ impl<'tcx> Visitor<'tcx> for IrMaps<'tcx> {
| hir::ExprKind::Struct(..)
| hir::ExprKind::Repeat(..)
| hir::ExprKind::InlineAsm(..)
+ | hir::ExprKind::OffsetOf(..)
| hir::ExprKind::Type(..)
| hir::ExprKind::Err(_)
| hir::ExprKind::Path(hir::QPath::TypeRelative(..))
@@ -591,8 +588,13 @@ impl<'a, 'tcx> Liveness<'a, 'tcx> {
}
fn assigned_on_exit(&self, ln: LiveNode, var: Variable) -> bool {
- let successor = self.successors[ln].unwrap();
- self.assigned_on_entry(successor, var)
+ match self.successors[ln] {
+ Some(successor) => self.assigned_on_entry(successor, var),
+ None => {
+ self.ir.tcx.sess.delay_span_bug(DUMMY_SP, "no successor");
+ true
+ }
+ }
}
fn write_vars<F>(&self, wr: &mut dyn Write, mut test: F) -> io::Result<()>
@@ -1129,7 +1131,8 @@ impl<'a, 'tcx> Liveness<'a, 'tcx> {
| hir::ExprKind::ConstBlock(..)
| hir::ExprKind::Err(_)
| hir::ExprKind::Path(hir::QPath::TypeRelative(..))
- | hir::ExprKind::Path(hir::QPath::LangItem(..)) => succ,
+ | hir::ExprKind::Path(hir::QPath::LangItem(..))
+ | hir::ExprKind::OffsetOf(..) => succ,
// Note that labels have been resolved, so we don't need to look
// at the label ident
@@ -1294,13 +1297,13 @@ impl<'a, 'tcx> Liveness<'a, 'tcx> {
self.exit_ln
}
- fn warn_about_unreachable(
+ fn warn_about_unreachable<'desc>(
&mut self,
orig_span: Span,
orig_ty: Ty<'tcx>,
expr_span: Span,
expr_id: HirId,
- descr: &str,
+ descr: &'desc str,
) {
if !orig_ty.is_never() {
// Unreachable code warnings are already emitted during type checking.
@@ -1313,22 +1316,15 @@ impl<'a, 'tcx> Liveness<'a, 'tcx> {
// that we do not emit the same warning twice if the uninhabited type
// is indeed `!`.
- let msg = format!("unreachable {}", descr);
- self.ir.tcx.struct_span_lint_hir(
+ self.ir.tcx.emit_spanned_lint(
lint::builtin::UNREACHABLE_CODE,
expr_id,
expr_span,
- &msg,
- |diag| {
- diag.span_label(expr_span, &msg)
- .span_label(orig_span, "any code following this expression is unreachable")
- .span_note(
- orig_span,
- &format!(
- "this expression has type `{}`, which is uninhabited",
- orig_ty
- ),
- )
+ errors::UnreachableDueToUninhabited {
+ expr: expr_span,
+ orig: orig_span,
+ descr,
+ ty: orig_ty,
},
);
}
@@ -1418,6 +1414,7 @@ fn check_expr<'tcx>(this: &mut Liveness<'_, 'tcx>, expr: &'tcx Expr<'tcx>) {
| hir::ExprKind::ConstBlock(..)
| hir::ExprKind::Block(..)
| hir::ExprKind::AddrOf(..)
+ | hir::ExprKind::OffsetOf(..)
| hir::ExprKind::Struct(..)
| hir::ExprKind::Repeat(..)
| hir::ExprKind::Closure { .. }
@@ -1479,23 +1476,21 @@ impl<'tcx> Liveness<'_, 'tcx> {
if self.used_on_entry(entry_ln, var) {
if !self.live_on_entry(entry_ln, var) {
if let Some(name) = self.should_warn(var) {
- self.ir.tcx.struct_span_lint_hir(
+ self.ir.tcx.emit_spanned_lint(
lint::builtin::UNUSED_ASSIGNMENTS,
var_hir_id,
vec![span],
- format!("value captured by `{}` is never read", name),
- |lint| lint.help("did you mean to capture by reference instead?"),
+ errors::UnusedCaptureMaybeCaptureRef { name },
);
}
}
} else {
if let Some(name) = self.should_warn(var) {
- self.ir.tcx.struct_span_lint_hir(
+ self.ir.tcx.emit_spanned_lint(
lint::builtin::UNUSED_VARIABLES,
var_hir_id,
vec![span],
- format!("unused variable: `{}`", name),
- |lint| lint.help("did you mean to capture by reference instead?"),
+ errors::UnusedVarMaybeCaptureRef { name },
);
}
}
@@ -1510,11 +1505,14 @@ impl<'tcx> Liveness<'_, 'tcx> {
Some(entry_ln),
Some(body),
|spans, hir_id, ln, var| {
- if !self.live_on_entry(ln, var) {
- self.report_unused_assign(hir_id, spans, var, |name| {
- format!("value passed to `{}` is never read", name)
- });
- }
+ if !self.live_on_entry(ln, var)
+ && let Some(name) = self.should_warn(var) {
+ self.ir.tcx.emit_spanned_lint(
+ lint::builtin::UNUSED_ASSIGNMENTS,
+ hir_id,
+ spans,
+ errors::UnusedAssignPassed { name },
+ ); }
},
);
}
@@ -1583,39 +1581,35 @@ impl<'tcx> Liveness<'_, 'tcx> {
if ln == self.exit_ln { false } else { self.assigned_on_exit(ln, var) };
if is_assigned {
- self.ir.tcx.struct_span_lint_hir(
+ self.ir.tcx.emit_spanned_lint(
lint::builtin::UNUSED_VARIABLES,
first_hir_id,
hir_ids_and_spans
.into_iter()
.map(|(_, _, ident_span)| ident_span)
.collect::<Vec<_>>(),
- format!("variable `{}` is assigned to, but never used", name),
- |lint| lint.note(&format!("consider using `_{}` instead", name)),
+ errors::UnusedVarAssignedOnly { name },
)
} else if can_remove {
- self.ir.tcx.struct_span_lint_hir(
+ let spans = hir_ids_and_spans
+ .iter()
+ .map(|(_, pat_span, _)| {
+ let span = self
+ .ir
+ .tcx
+ .sess
+ .source_map()
+ .span_extend_to_next_char(*pat_span, ',', true);
+ span.with_hi(BytePos(span.hi().0 + 1))
+ })
+ .collect();
+ self.ir.tcx.emit_spanned_lint(
lint::builtin::UNUSED_VARIABLES,
first_hir_id,
hir_ids_and_spans.iter().map(|(_, pat_span, _)| *pat_span).collect::<Vec<_>>(),
- format!("unused variable: `{}`", name),
- |lint| {
- lint.multipart_suggestion(
- "try removing the field",
- hir_ids_and_spans
- .iter()
- .map(|(_, pat_span, _)| {
- let span = self
- .ir
- .tcx
- .sess
- .source_map()
- .span_extend_to_next_char(*pat_span, ',', true);
- (span.with_hi(BytePos(span.hi().0 + 1)), String::new())
- })
- .collect(),
- Applicability::MachineApplicable,
- )
+ errors::UnusedVarRemoveField {
+ name,
+ sugg: errors::UnusedVarRemoveFieldSugg { spans },
},
);
} else {
@@ -1629,55 +1623,46 @@ impl<'tcx> Liveness<'_, 'tcx> {
// the field" message, and suggest `_` for the non-shorthands. If we only
// have non-shorthand, then prefix with an underscore instead.
if !shorthands.is_empty() {
- let shorthands = shorthands
- .into_iter()
- .map(|(_, pat_span, _)| (pat_span, format!("{}: _", name)))
- .chain(
- non_shorthands
- .into_iter()
- .map(|(_, pat_span, _)| (pat_span, "_".to_string())),
- )
- .collect::<Vec<_>>();
+ let shorthands =
+ shorthands.into_iter().map(|(_, pat_span, _)| pat_span).collect();
+ let non_shorthands =
+ non_shorthands.into_iter().map(|(_, pat_span, _)| pat_span).collect();
- self.ir.tcx.struct_span_lint_hir(
+ self.ir.tcx.emit_spanned_lint(
lint::builtin::UNUSED_VARIABLES,
first_hir_id,
hir_ids_and_spans
.iter()
.map(|(_, pat_span, _)| *pat_span)
.collect::<Vec<_>>(),
- format!("unused variable: `{}`", name),
- |lint| {
- lint.multipart_suggestion(
- "try ignoring the field",
+ errors::UnusedVarTryIgnore {
+ sugg: errors::UnusedVarTryIgnoreSugg {
shorthands,
- Applicability::MachineApplicable,
- )
+ non_shorthands,
+ name,
+ },
},
);
} else {
let non_shorthands = non_shorthands
.into_iter()
- .map(|(_, _, ident_span)| (ident_span, format!("_{}", name)))
+ .map(|(_, _, ident_span)| ident_span)
.collect::<Vec<_>>();
-
- self.ir.tcx.struct_span_lint_hir(
+ let suggestions = self.string_interp_suggestions(&name, opt_body);
+ self.ir.tcx.emit_spanned_lint(
lint::builtin::UNUSED_VARIABLES,
first_hir_id,
hir_ids_and_spans
.iter()
.map(|(_, _, ident_span)| *ident_span)
.collect::<Vec<_>>(),
- format!("unused variable: `{}`", name),
- |lint| {
- if self.has_added_lit_match_name_span(&name, opt_body, lint) {
- lint.span_label(pat.span, "unused variable");
- }
- lint.multipart_suggestion(
- "if this is intentional, prefix it with an underscore",
- non_shorthands,
- Applicability::MachineApplicable,
- )
+ errors::UnusedVariableTryPrefix {
+ label: if !suggestions.is_empty() { Some(pat.span) } else { None },
+ sugg: errors::UnusedVariableTryPrefixSugg {
+ spans: non_shorthands,
+ name,
+ },
+ string_interp: suggestions,
},
);
}
@@ -1685,65 +1670,40 @@ impl<'tcx> Liveness<'_, 'tcx> {
}
}
- fn has_added_lit_match_name_span(
+ fn string_interp_suggestions(
&self,
name: &str,
opt_body: Option<&hir::Body<'_>>,
- err: &mut Diagnostic,
- ) -> bool {
- let mut has_litstring = false;
- let Some(opt_body) = opt_body else {return false;};
+ ) -> Vec<errors::UnusedVariableStringInterp> {
+ let mut suggs = Vec::new();
+ let Some(opt_body) = opt_body else { return suggs; };
let mut visitor = CollectLitsVisitor { lit_exprs: vec![] };
intravisit::walk_body(&mut visitor, opt_body);
for lit_expr in visitor.lit_exprs {
let hir::ExprKind::Lit(litx) = &lit_expr.kind else { continue };
let rustc_ast::LitKind::Str(syb, _) = litx.node else{ continue; };
let name_str: &str = syb.as_str();
- let mut name_pa = String::from("{");
- name_pa.push_str(&name);
- name_pa.push('}');
+ let name_pa = format!("{{{name}}}");
if name_str.contains(&name_pa) {
- err.span_label(
- lit_expr.span,
- "you might have meant to use string interpolation in this string literal",
- );
- err.multipart_suggestion(
- "string interpolation only works in `format!` invocations",
- vec![
- (lit_expr.span.shrink_to_lo(), "format!(".to_string()),
- (lit_expr.span.shrink_to_hi(), ")".to_string()),
- ],
- Applicability::MachineApplicable,
- );
- has_litstring = true;
+ suggs.push(errors::UnusedVariableStringInterp {
+ lit: lit_expr.span,
+ lo: lit_expr.span.shrink_to_lo(),
+ hi: lit_expr.span.shrink_to_hi(),
+ });
}
}
- has_litstring
+ suggs
}
fn warn_about_dead_assign(&self, spans: Vec<Span>, hir_id: HirId, ln: LiveNode, var: Variable) {
- if !self.live_on_exit(ln, var) {
- self.report_unused_assign(hir_id, spans, var, |name| {
- format!("value assigned to `{}` is never read", name)
- });
- }
- }
-
- fn report_unused_assign(
- &self,
- hir_id: HirId,
- spans: Vec<Span>,
- var: Variable,
- message: impl Fn(&str) -> String,
- ) {
- if let Some(name) = self.should_warn(var) {
- self.ir.tcx.struct_span_lint_hir(
- lint::builtin::UNUSED_ASSIGNMENTS,
- hir_id,
- spans,
- message(&name),
- |lint| lint.help("maybe it is overwritten before being read?"),
- )
- }
+ if !self.live_on_exit(ln, var)
+ && let Some(name) = self.should_warn(var) {
+ self.ir.tcx.emit_spanned_lint(
+ lint::builtin::UNUSED_ASSIGNMENTS,
+ hir_id,
+ spans,
+ errors::UnusedAssign { name },
+ );
+ }
}
}