Rollup merge of #109358 - petrochenkov:nosess, r=cjgillot

rustc: Remove unused `Session` argument from some attribute functions

(One auxiliary test file containing one of these functions was unused, so I removed it instead of updating.)

compiler/rustc_ast/src/attr/mod.rs

@@ -180,6 +180,12 @@ impl Attribute {
         self.doc_str().map_or(false, |s| comments::may_have_doc_links(s.as_str()))
     }
 
+    pub fn is_proc_macro_attr(&self) -> bool {
+        [sym::proc_macro, sym::proc_macro_attribute, sym::proc_macro_derive]
+            .iter()
+            .any(|kind| self.has_name(*kind))
+    }
+
     /// Extracts the MetaItem from inside this Attribute.
     pub fn meta(&self) -> Option<MetaItem> {
         match &self.kind {
@@ -627,6 +633,22 @@ pub fn mk_attr_name_value_str(
     mk_attr(g, style, path, args, span)
 }
 
+pub fn filter_by_name(attrs: &[Attribute], name: Symbol) -> impl Iterator<Item = &Attribute> {
+    attrs.iter().filter(move |attr| attr.has_name(name))
+}
+
+pub fn find_by_name(attrs: &[Attribute], name: Symbol) -> Option<&Attribute> {
+    filter_by_name(attrs, name).next()
+}
+
+pub fn first_attr_value_str_by_name(attrs: &[Attribute], name: Symbol) -> Option<Symbol> {
+    find_by_name(attrs, name).and_then(|attr| attr.value_str())
+}
+
+pub fn contains_name(attrs: &[Attribute], name: Symbol) -> bool {
+    find_by_name(attrs, name).is_some()
+}
+
 pub fn list_contains_name(items: &[NestedMetaItem], name: Symbol) -> bool {
     items.iter().any(|item| item.has_name(name))
 }

compiler/rustc_ast_lowering/src/lib.rs

@@ -2185,7 +2185,7 @@ impl<'a, 'hir> LoweringContext<'a, 'hir> {
             def_id: self.local_def_id(param.id),
             name,
             span: self.lower_span(param.span()),
-            pure_wrt_drop: self.tcx.sess.contains_name(&param.attrs, sym::may_dangle),
+            pure_wrt_drop: attr::contains_name(&param.attrs, sym::may_dangle),
             kind,
             colon_span: param.colon_span.map(|s| self.lower_span(s)),
             source,

compiler/rustc_ast_passes/src/ast_validation.rs

@@ -799,11 +799,11 @@ impl<'a> Visitor<'a> for AstValidator<'a> {
     }
 
     fn visit_item(&mut self, item: &'a Item) {
-        if item.attrs.iter().any(|attr| self.session.is_proc_macro_attr(attr)) {
+        if item.attrs.iter().any(|attr| attr.is_proc_macro_attr()) {
             self.has_proc_macro_decls = true;
         }
 
-        if self.session.contains_name(&item.attrs, sym::no_mangle) {
+        if attr::contains_name(&item.attrs, sym::no_mangle) {
             self.check_nomangle_item_asciionly(item.ident, item.span);
         }
 
@@ -973,7 +973,7 @@ impl<'a> Visitor<'a> for AstValidator<'a> {
                 }
                 // Ensure that `path` attributes on modules are recorded as used (cf. issue #35584).
                 if !matches!(mod_kind, ModKind::Loaded(_, Inline::Yes, _))
-                    && !self.session.contains_name(&item.attrs, sym::path)
+                    && !attr::contains_name(&item.attrs, sym::path)
                 {
                     self.check_mod_file_item_asciionly(item.ident);
                 }
@@ -1248,7 +1248,7 @@ impl<'a> Visitor<'a> for AstValidator<'a> {
     }
 
     fn visit_assoc_item(&mut self, item: &'a AssocItem, ctxt: AssocCtxt) {
-        if self.session.contains_name(&item.attrs, sym::no_mangle) {
+        if attr::contains_name(&item.attrs, sym::no_mangle) {
             self.check_nomangle_item_asciionly(item.ident, item.span);
         }
 

compiler/rustc_ast_passes/src/feature_gate.rs

@@ -1,6 +1,6 @@
 use rustc_ast as ast;
 use rustc_ast::visit::{self, AssocCtxt, FnCtxt, FnKind, Visitor};
-use rustc_ast::{AssocConstraint, AssocConstraintKind, NodeId};
+use rustc_ast::{attr, AssocConstraint, AssocConstraintKind, NodeId};
 use rustc_ast::{PatKind, RangeEnd};
 use rustc_errors::{Applicability, StashKey};
 use rustc_feature::{AttributeGate, BuiltinAttribute, Features, GateIssue, BUILTIN_ATTRIBUTE_MAP};
@@ -232,7 +232,7 @@ impl<'a> Visitor<'a> for PostExpansionVisitor<'a> {
             }
 
             ast::ItemKind::Fn(..) => {
-                if self.sess.contains_name(&i.attrs, sym::start) {
+                if attr::contains_name(&i.attrs, sym::start) {
                     gate_feature_post!(
                         &self,
                         start,
@@ -245,7 +245,7 @@ impl<'a> Visitor<'a> for PostExpansionVisitor<'a> {
             }
 
             ast::ItemKind::Struct(..) => {
-                for attr in self.sess.filter_by_name(&i.attrs, sym::repr) {
+                for attr in attr::filter_by_name(&i.attrs, sym::repr) {
                     for item in attr.meta_item_list().unwrap_or_else(ThinVec::new) {
                         if item.has_name(sym::simd) {
                             gate_feature_post!(
@@ -306,7 +306,7 @@ impl<'a> Visitor<'a> for PostExpansionVisitor<'a> {
     fn visit_foreign_item(&mut self, i: &'a ast::ForeignItem) {
         match i.kind {
             ast::ForeignItemKind::Fn(..) | ast::ForeignItemKind::Static(..) => {
-                let link_name = self.sess.first_attr_value_str_by_name(&i.attrs, sym::link_name);
+                let link_name = attr::first_attr_value_str_by_name(&i.attrs, sym::link_name);
                 let links_to_llvm =
                     link_name.map_or(false, |val| val.as_str().starts_with("llvm."));
                 if links_to_llvm {

compiler/rustc_attr/src/builtin.rs

@@ -1,6 +1,6 @@
 //! Parsing and validation of builtin attributes
 
-use rustc_ast as ast;
+use rustc_ast::{self as ast, attr};
 use rustc_ast::{Attribute, LitKind, MetaItem, MetaItemKind, MetaItemLit, NestedMetaItem, NodeId};
 use rustc_ast_pretty::pprust;
 use rustc_feature::{find_gated_cfg, is_builtin_attr_name, Features, GatedCfg};
@@ -556,8 +556,8 @@ where
     (stab, const_stab, body_stab)
 }
 
-pub fn find_crate_name(sess: &Session, attrs: &[Attribute]) -> Option<Symbol> {
+pub fn find_crate_name(attrs: &[Attribute]) -> Option<Symbol> {
-    sess.first_attr_value_str_by_name(attrs, sym::crate_name)
+    attr::first_attr_value_str_by_name(attrs, sym::crate_name)
 }
 
 #[derive(Clone, Debug)]
@@ -1177,7 +1177,7 @@ fn allow_unstable<'a>(
     attrs: &'a [Attribute],
     symbol: Symbol,
 ) -> impl Iterator<Item = Symbol> + 'a {
-    let attrs = sess.filter_by_name(attrs, symbol);
+    let attrs = attr::filter_by_name(attrs, symbol);
     let list = attrs
         .filter_map(move |attr| {
             attr.meta_item_list().or_else(|| {

compiler/rustc_builtin_macros/src/deriving/default.rs

@@ -1,7 +1,7 @@
 use crate::deriving::generic::ty::*;
 use crate::deriving::generic::*;
 use rustc_ast as ast;
-use rustc_ast::{walk_list, EnumDef, VariantData};
+use rustc_ast::{attr, walk_list, EnumDef, VariantData};
 use rustc_errors::Applicability;
 use rustc_expand::base::{Annotatable, DummyResult, ExtCtxt};
 use rustc_span::symbol::Ident;
@@ -106,7 +106,7 @@ fn extract_default_variant<'a>(
     let default_variants: SmallVec<[_; 1]> = enum_def
         .variants
         .iter()
-        .filter(|variant| cx.sess.contains_name(&variant.attrs, kw::Default))
+        .filter(|variant| attr::contains_name(&variant.attrs, kw::Default))
         .collect();
 
     let variant = match default_variants.as_slice() {
@@ -116,7 +116,7 @@ fn extract_default_variant<'a>(
                 .variants
                 .iter()
                 .filter(|variant| matches!(variant.data, VariantData::Unit(..)))
-                .filter(|variant| !cx.sess.contains_name(&variant.attrs, sym::non_exhaustive));
+                .filter(|variant| !attr::contains_name(&variant.attrs, sym::non_exhaustive));
 
             let mut diag = cx.struct_span_err(trait_span, "no default declared");
             diag.help("make a unit variant default by placing `#[default]` above it");
@@ -146,7 +146,7 @@ fn extract_default_variant<'a>(
                         if v.span == variant.span {
                             None
                         } else {
-                            Some((cx.sess.find_by_name(&v.attrs, kw::Default)?.span, String::new()))
+                            Some((attr::find_by_name(&v.attrs, kw::Default)?.span, String::new()))
                         }
                     })
                     .collect();
@@ -174,7 +174,7 @@ fn extract_default_variant<'a>(
         return Err(());
     }
 
-    if let Some(non_exhaustive_attr) = cx.sess.find_by_name(&variant.attrs, sym::non_exhaustive) {
+    if let Some(non_exhaustive_attr) = attr::find_by_name(&variant.attrs, sym::non_exhaustive) {
         cx.struct_span_err(variant.ident.span, "default variant must be exhaustive")
             .span_label(non_exhaustive_attr.span, "declared `#[non_exhaustive]` here")
             .help("consider a manual implementation of `Default`")
@@ -191,7 +191,7 @@ fn validate_default_attribute(
     default_variant: &rustc_ast::Variant,
 ) -> Result<(), ()> {
     let attrs: SmallVec<[_; 1]> =
-        cx.sess.filter_by_name(&default_variant.attrs, kw::Default).collect();
+        attr::filter_by_name(&default_variant.attrs, kw::Default).collect();
 
     let attr = match attrs.as_slice() {
         [attr] => attr,

compiler/rustc_builtin_macros/src/proc_macro_harness.rs

@@ -1,6 +1,6 @@
 use rustc_ast::ptr::P;
 use rustc_ast::visit::{self, Visitor};
-use rustc_ast::{self as ast, NodeId};
+use rustc_ast::{self as ast, attr, NodeId};
 use rustc_ast_pretty::pprust;
 use rustc_expand::base::{parse_macro_name_and_helper_attrs, ExtCtxt, ResolverExpand};
 use rustc_expand::expand::{AstFragment, ExpansionConfig};
@@ -34,7 +34,6 @@ enum ProcMacro {
 }
 
 struct CollectProcMacros<'a> {
-    sess: &'a Session,
     macros: Vec<ProcMacro>,
     in_root: bool,
     handler: &'a rustc_errors::Handler,
@@ -56,7 +55,6 @@ pub fn inject(
     let mut cx = ExtCtxt::new(sess, ecfg, resolver, None);
 
     let mut collect = CollectProcMacros {
-        sess,
         macros: Vec::new(),
         in_root: true,
         handler,
@@ -160,7 +158,7 @@ impl<'a> CollectProcMacros<'a> {
 impl<'a> Visitor<'a> for CollectProcMacros<'a> {
     fn visit_item(&mut self, item: &'a ast::Item) {
         if let ast::ItemKind::MacroDef(..) = item.kind {
-            if self.is_proc_macro_crate && self.sess.contains_name(&item.attrs, sym::macro_export) {
+            if self.is_proc_macro_crate && attr::contains_name(&item.attrs, sym::macro_export) {
                 let msg =
                     "cannot export macro_rules! macros from a `proc-macro` crate type currently";
                 self.handler.span_err(self.source_map.guess_head_span(item.span), msg);
@@ -176,7 +174,7 @@ impl<'a> Visitor<'a> for CollectProcMacros<'a> {
         let mut found_attr: Option<&'a ast::Attribute> = None;
 
         for attr in &item.attrs {
-            if self.sess.is_proc_macro_attr(&attr) {
+            if attr.is_proc_macro_attr() {
                 if let Some(prev_attr) = found_attr {
                     let prev_item = prev_attr.get_normal_item();
                     let item = attr.get_normal_item();

compiler/rustc_builtin_macros/src/standard_library_imports.rs

@@ -1,4 +1,4 @@
-use rustc_ast as ast;
+use rustc_ast::{self as ast, attr};
 use rustc_expand::base::{ExtCtxt, ResolverExpand};
 use rustc_expand::expand::ExpansionConfig;
 use rustc_session::Session;
@@ -16,10 +16,10 @@ pub fn inject(
     let edition = sess.parse_sess.edition;
 
     // the first name in this list is the crate name of the crate with the prelude
-    let names: &[Symbol] = if sess.contains_name(&krate.attrs, sym::no_core) {
+    let names: &[Symbol] = if attr::contains_name(&krate.attrs, sym::no_core) {
         return krate;
-    } else if sess.contains_name(&krate.attrs, sym::no_std) {
+    } else if attr::contains_name(&krate.attrs, sym::no_std) {
-        if sess.contains_name(&krate.attrs, sym::compiler_builtins) {
+        if attr::contains_name(&krate.attrs, sym::compiler_builtins) {
             &[sym::core]
         } else {
             &[sym::core, sym::compiler_builtins]

compiler/rustc_builtin_macros/src/test.rs

@@ -1,12 +1,11 @@
 /// The expansion from a test function to the appropriate test struct for libtest
 /// Ideally, this code would be in libtest but for efficiency and error messages it lives here.
 use crate::util::{check_builtin_macro_attribute, warn_on_duplicate_attribute};
-use rustc_ast as ast;
 use rustc_ast::ptr::P;
+use rustc_ast::{self as ast, attr};
 use rustc_ast_pretty::pprust;
 use rustc_errors::Applicability;
 use rustc_expand::base::*;
-use rustc_session::Session;
 use rustc_span::symbol::{sym, Ident, Symbol};
 use rustc_span::{FileNameDisplayPreference, Span};
 use std::iter;
@@ -291,14 +290,11 @@ pub fn expand_test_or_bench(
                                         ),
                                     ),
                                     // ignore: true | false
-                                    field(
+                                    field("ignore", cx.expr_bool(sp, should_ignore(&item)),),
-                                        "ignore",
-                                        cx.expr_bool(sp, should_ignore(&cx.sess, &item)),
-                                    ),
                                     // ignore_message: Some("...") | None
                                     field(
                                         "ignore_message",
-                                        if let Some(msg) = should_ignore_message(cx, &item) {
+                                        if let Some(msg) = should_ignore_message(&item) {
                                             cx.expr_some(sp, cx.expr_str(sp, msg))
                                         } else {
                                             cx.expr_none(sp)
@@ -425,12 +421,12 @@ enum ShouldPanic {
     Yes(Option<Symbol>),
 }
 
-fn should_ignore(sess: &Session, i: &ast::Item) -> bool {
+fn should_ignore(i: &ast::Item) -> bool {
-    sess.contains_name(&i.attrs, sym::ignore)
+    attr::contains_name(&i.attrs, sym::ignore)
 }
 
-fn should_ignore_message(cx: &ExtCtxt<'_>, i: &ast::Item) -> Option<Symbol> {
+fn should_ignore_message(i: &ast::Item) -> Option<Symbol> {
-    match cx.sess.find_by_name(&i.attrs, sym::ignore) {
+    match attr::find_by_name(&i.attrs, sym::ignore) {
         Some(attr) => {
             match attr.meta_item_list() {
                 // Handle #[ignore(bar = "foo")]
@@ -444,7 +440,7 @@ fn should_ignore_message(cx: &ExtCtxt<'_>, i: &ast::Item) -> Option<Symbol> {
 }
 
 fn should_panic(cx: &ExtCtxt<'_>, i: &ast::Item) -> ShouldPanic {
-    match cx.sess.find_by_name(&i.attrs, sym::should_panic) {
+    match attr::find_by_name(&i.attrs, sym::should_panic) {
         Some(attr) => {
             let sd = &cx.sess.parse_sess.span_diagnostic;
 
@@ -510,7 +506,7 @@ fn test_type(cx: &ExtCtxt<'_>) -> TestType {
 }
 
 fn has_test_signature(cx: &ExtCtxt<'_>, i: &ast::Item) -> bool {
-    let has_should_panic_attr = cx.sess.contains_name(&i.attrs, sym::should_panic);
+    let has_should_panic_attr = attr::contains_name(&i.attrs, sym::should_panic);
     let sd = &cx.sess.parse_sess.span_diagnostic;
     match &i.kind {
         ast::ItemKind::Fn(box ast::Fn { sig, generics, .. }) => {

compiler/rustc_builtin_macros/src/test_harness.rs

@@ -47,11 +47,11 @@ pub fn inject(sess: &Session, resolver: &mut dyn ResolverExpand, krate: &mut ast
     // unconditional, so that the attribute is still marked as used in
     // non-test builds.
     let reexport_test_harness_main =
-        sess.first_attr_value_str_by_name(&krate.attrs, sym::reexport_test_harness_main);
+        attr::first_attr_value_str_by_name(&krate.attrs, sym::reexport_test_harness_main);
 
     // Do this here so that the test_runner crate attribute gets marked as used
     // even in non-test builds
-    let test_runner = get_test_runner(sess, span_diagnostic, &krate);
+    let test_runner = get_test_runner(span_diagnostic, &krate);
 
     if sess.opts.test {
         let panic_strategy = match (panic_strategy, sess.opts.unstable_opts.panic_abort_tests) {
@@ -123,7 +123,7 @@ impl<'a> MutVisitor for TestHarnessGenerator<'a> {
 
     fn flat_map_item(&mut self, i: P<ast::Item>) -> SmallVec<[P<ast::Item>; 1]> {
         let mut item = i.into_inner();
-        if let Some(name) = get_test_name(&self.cx.ext_cx.sess, &item) {
+        if let Some(name) = get_test_name(&item) {
             debug!("this is a test item");
 
             let test = Test { span: item.span, ident: item.ident, name };
@@ -145,12 +145,12 @@ impl<'a> MutVisitor for TestHarnessGenerator<'a> {
 
 // Beware, this is duplicated in librustc_passes/entry.rs (with
 // `rustc_hir::Item`), so make sure to keep them in sync.
-fn entry_point_type(sess: &Session, item: &ast::Item, depth: usize) -> EntryPointType {
+fn entry_point_type(item: &ast::Item, depth: usize) -> EntryPointType {
     match item.kind {
         ast::ItemKind::Fn(..) => {
-            if sess.contains_name(&item.attrs, sym::start) {
+            if attr::contains_name(&item.attrs, sym::start) {
                 EntryPointType::Start
-            } else if sess.contains_name(&item.attrs, sym::rustc_main) {
+            } else if attr::contains_name(&item.attrs, sym::rustc_main) {
                 EntryPointType::RustcMainAttr
             } else if item.ident.name == sym::main {
                 if depth == 0 {
@@ -184,7 +184,7 @@ impl<'a> MutVisitor for EntryPointCleaner<'a> {
         // Remove any #[rustc_main] or #[start] from the AST so it doesn't
         // clash with the one we're going to add, but mark it as
         // #[allow(dead_code)] to avoid printing warnings.
-        let item = match entry_point_type(self.sess, &item, self.depth) {
+        let item = match entry_point_type(&item, self.depth) {
             EntryPointType::MainNamed | EntryPointType::RustcMainAttr | EntryPointType::Start => {
                 item.map(|ast::Item { id, ident, attrs, kind, vis, span, tokens }| {
                     let allow_dead_code = attr::mk_attr_nested_word(
@@ -373,16 +373,12 @@ fn mk_tests_slice(cx: &TestCtxt<'_>, sp: Span) -> P<ast::Expr> {
     )
 }
 
-fn get_test_name(sess: &Session, i: &ast::Item) -> Option<Symbol> {
+fn get_test_name(i: &ast::Item) -> Option<Symbol> {
-    sess.first_attr_value_str_by_name(&i.attrs, sym::rustc_test_marker)
+    attr::first_attr_value_str_by_name(&i.attrs, sym::rustc_test_marker)
 }
 
-fn get_test_runner(
+fn get_test_runner(sd: &rustc_errors::Handler, krate: &ast::Crate) -> Option<ast::Path> {
-    sess: &Session,
+    let test_attr = attr::find_by_name(&krate.attrs, sym::test_runner)?;
-    sd: &rustc_errors::Handler,
-    krate: &ast::Crate,
-) -> Option<ast::Path> {
-    let test_attr = sess.find_by_name(&krate.attrs, sym::test_runner)?;
     let meta_list = test_attr.meta_item_list()?;
     let span = test_attr.span;
     match &*meta_list {

compiler/rustc_builtin_macros/src/util.rs

@@ -1,4 +1,4 @@
-use rustc_ast::{AttrStyle, Attribute, MetaItem};
+use rustc_ast::{attr, AttrStyle, Attribute, MetaItem};
 use rustc_expand::base::{Annotatable, ExtCtxt};
 use rustc_feature::AttributeTemplate;
 use rustc_lint_defs::builtin::DUPLICATE_MACRO_ATTRIBUTES;
@@ -36,7 +36,7 @@ pub fn warn_on_duplicate_attribute(ecx: &ExtCtxt<'_>, item: &Annotatable, name:
         _ => None,
     };
     if let Some(attrs) = attrs {
-        if let Some(attr) = ecx.sess.find_by_name(attrs, name) {
+        if let Some(attr) = attr::find_by_name(attrs, name) {
             ecx.parse_sess().buffer_lint(
                 DUPLICATE_MACRO_ATTRIBUTES,
                 attr.span,

compiler/rustc_codegen_llvm/src/debuginfo/gdb.rs

@@ -5,12 +5,12 @@ use crate::llvm;
 use crate::builder::Builder;
 use crate::common::CodegenCx;
 use crate::value::Value;
+use rustc_ast::attr;
 use rustc_codegen_ssa::base::collect_debugger_visualizers_transitive;
 use rustc_codegen_ssa::traits::*;
 use rustc_hir::def_id::LOCAL_CRATE;
 use rustc_middle::bug;
 use rustc_session::config::{CrateType, DebugInfo};
-
 use rustc_span::symbol::sym;
 use rustc_span::DebuggerVisualizerType;
 
@@ -87,7 +87,7 @@ pub fn get_or_insert_gdb_debug_scripts_section_global<'ll>(cx: &CodegenCx<'ll, '
 
 pub fn needs_gdb_debug_scripts_section(cx: &CodegenCx<'_, '_>) -> bool {
     let omit_gdb_pretty_printer_section =
-        cx.tcx.sess.contains_name(cx.tcx.hir().krate_attrs(), sym::omit_gdb_pretty_printer_section);
+        attr::contains_name(cx.tcx.hir().krate_attrs(), sym::omit_gdb_pretty_printer_section);
 
     // To ensure the section `__rustc_debug_gdb_scripts_section__` will not create
     // ODR violations at link time, this section will not be emitted for rlibs since

compiler/rustc_codegen_ssa/src/back/write.rs

@@ -8,6 +8,7 @@ use crate::{
     CachedModuleCodegen, CodegenResults, CompiledModule, CrateInfo, ModuleCodegen, ModuleKind,
 };
 use jobserver::{Acquired, Client};
+use rustc_ast::attr;
 use rustc_data_structures::fx::FxHashMap;
 use rustc_data_structures::memmap::Mmap;
 use rustc_data_structures::profiling::SelfProfilerRef;
@@ -447,8 +448,8 @@ pub fn start_async_codegen<B: ExtraBackendMethods>(
     let sess = tcx.sess;
 
     let crate_attrs = tcx.hir().attrs(rustc_hir::CRATE_HIR_ID);
-    let no_builtins = tcx.sess.contains_name(crate_attrs, sym::no_builtins);
+    let no_builtins = attr::contains_name(crate_attrs, sym::no_builtins);
-    let is_compiler_builtins = tcx.sess.contains_name(crate_attrs, sym::compiler_builtins);
+    let is_compiler_builtins = attr::contains_name(crate_attrs, sym::compiler_builtins);
 
     let crate_info = CrateInfo::new(tcx, target_cpu);
 

compiler/rustc_codegen_ssa/src/base.rs

@@ -809,7 +809,7 @@ impl CrateInfo {
             .collect();
         let local_crate_name = tcx.crate_name(LOCAL_CRATE);
         let crate_attrs = tcx.hir().attrs(rustc_hir::CRATE_HIR_ID);
-        let subsystem = tcx.sess.first_attr_value_str_by_name(crate_attrs, sym::windows_subsystem);
+        let subsystem = attr::first_attr_value_str_by_name(crate_attrs, sym::windows_subsystem);
         let windows_subsystem = subsystem.map(|subsystem| {
             if subsystem != sym::windows && subsystem != sym::console {
                 tcx.sess.emit_fatal(errors::InvalidWindowsSubsystem { subsystem });

compiler/rustc_expand/src/base.rs

@@ -776,16 +776,14 @@ impl SyntaxExtension {
         let allow_internal_unstable =
             attr::allow_internal_unstable(sess, &attrs).collect::<Vec<Symbol>>();
 
-        let allow_internal_unsafe = sess.contains_name(attrs, sym::allow_internal_unsafe);
+        let allow_internal_unsafe = attr::contains_name(attrs, sym::allow_internal_unsafe);
-        let local_inner_macros = sess
+        let local_inner_macros = attr::find_by_name(attrs, sym::macro_export)
-            .find_by_name(attrs, sym::macro_export)
             .and_then(|macro_export| macro_export.meta_item_list())
             .map_or(false, |l| attr::list_contains_name(&l, sym::local_inner_macros));
-        let collapse_debuginfo = sess.contains_name(attrs, sym::collapse_debuginfo);
+        let collapse_debuginfo = attr::contains_name(attrs, sym::collapse_debuginfo);
         tracing::debug!(?local_inner_macros, ?collapse_debuginfo, ?allow_internal_unsafe);
 
-        let (builtin_name, helper_attrs) = sess
+        let (builtin_name, helper_attrs) = attr::find_by_name(attrs, sym::rustc_builtin_macro)
-            .find_by_name(attrs, sym::rustc_builtin_macro)
             .map(|attr| {
                 // Override `helper_attrs` passed above if it's a built-in macro,
                 // marking `proc_macro_derive` macros as built-in is not a realistic use case.

compiler/rustc_interface/src/proc_macro_decls.rs

@@ -1,3 +1,4 @@
+use rustc_ast::attr;
 use rustc_hir::def_id::LocalDefId;
 use rustc_middle::ty::query::Providers;
 use rustc_middle::ty::TyCtxt;
@@ -8,7 +9,7 @@ fn proc_macro_decls_static(tcx: TyCtxt<'_>, (): ()) -> Option<LocalDefId> {
 
     for id in tcx.hir().items() {
         let attrs = tcx.hir().attrs(id.hir_id());
-        if tcx.sess.contains_name(attrs, sym::rustc_proc_macro_decls) {
+        if attr::contains_name(attrs, sym::rustc_proc_macro_decls) {
             decls = Some(id.owner_id.def_id);
         }
     }

compiler/rustc_interface/src/util.rs

@@ -505,7 +505,7 @@ pub fn build_output_filenames(attrs: &[ast::Attribute], sess: &Session) -> Outpu
                 .opts
                 .crate_name
                 .clone()
-                .or_else(|| rustc_attr::find_crate_name(sess, attrs).map(|n| n.to_string()))
+                .or_else(|| rustc_attr::find_crate_name(attrs).map(|n| n.to_string()))
                 .unwrap_or_else(|| sess.io.input.filestem().to_owned());
 
             OutputFilenames::new(

compiler/rustc_lint/src/builtin.rs

@@ -358,29 +358,29 @@ impl EarlyLintPass for UnsafeCode {
             }
 
             ast::ItemKind::Fn(..) => {
-                if let Some(attr) = cx.sess().find_by_name(&it.attrs, sym::no_mangle) {
+                if let Some(attr) = attr::find_by_name(&it.attrs, sym::no_mangle) {
                     self.report_unsafe(cx, attr.span, BuiltinUnsafe::NoMangleFn);
                 }
 
-                if let Some(attr) = cx.sess().find_by_name(&it.attrs, sym::export_name) {
+                if let Some(attr) = attr::find_by_name(&it.attrs, sym::export_name) {
                     self.report_unsafe(cx, attr.span, BuiltinUnsafe::ExportNameFn);
                 }
 
-                if let Some(attr) = cx.sess().find_by_name(&it.attrs, sym::link_section) {
+                if let Some(attr) = attr::find_by_name(&it.attrs, sym::link_section) {
                     self.report_unsafe(cx, attr.span, BuiltinUnsafe::LinkSectionFn);
                 }
             }
 
             ast::ItemKind::Static(..) => {
-                if let Some(attr) = cx.sess().find_by_name(&it.attrs, sym::no_mangle) {
+                if let Some(attr) = attr::find_by_name(&it.attrs, sym::no_mangle) {
                     self.report_unsafe(cx, attr.span, BuiltinUnsafe::NoMangleStatic);
                 }
 
-                if let Some(attr) = cx.sess().find_by_name(&it.attrs, sym::export_name) {
+                if let Some(attr) = attr::find_by_name(&it.attrs, sym::export_name) {
                     self.report_unsafe(cx, attr.span, BuiltinUnsafe::ExportNameStatic);
                 }
 
-                if let Some(attr) = cx.sess().find_by_name(&it.attrs, sym::link_section) {
+                if let Some(attr) = attr::find_by_name(&it.attrs, sym::link_section) {
                     self.report_unsafe(cx, attr.span, BuiltinUnsafe::LinkSectionStatic);
                 }
             }
@@ -391,10 +391,10 @@ impl EarlyLintPass for UnsafeCode {
 
     fn check_impl_item(&mut self, cx: &EarlyContext<'_>, it: &ast::AssocItem) {
         if let ast::AssocItemKind::Fn(..) = it.kind {
-            if let Some(attr) = cx.sess().find_by_name(&it.attrs, sym::no_mangle) {
+            if let Some(attr) = attr::find_by_name(&it.attrs, sym::no_mangle) {
                 self.report_unsafe(cx, attr.span, BuiltinUnsafe::NoMangleMethod);
             }
-            if let Some(attr) = cx.sess().find_by_name(&it.attrs, sym::export_name) {
+            if let Some(attr) = attr::find_by_name(&it.attrs, sym::export_name) {
                 self.report_unsafe(cx, attr.span, BuiltinUnsafe::ExportNameMethod);
             }
         }
@@ -1123,12 +1123,12 @@ impl<'tcx> LateLintPass<'tcx> for InvalidNoMangleItems {
         };
         match it.kind {
             hir::ItemKind::Fn(.., ref generics, _) => {
-                if let Some(no_mangle_attr) = cx.sess().find_by_name(attrs, sym::no_mangle) {
+                if let Some(no_mangle_attr) = attr::find_by_name(attrs, sym::no_mangle) {
                     check_no_mangle_on_generic_fn(no_mangle_attr, None, generics, it.span);
                 }
             }
             hir::ItemKind::Const(..) => {
-                if cx.sess().contains_name(attrs, sym::no_mangle) {
+                if attr::contains_name(attrs, sym::no_mangle) {
                     // account for "pub const" (#45562)
                     let start = cx
                         .tcx
@@ -1152,9 +1152,8 @@ impl<'tcx> LateLintPass<'tcx> for InvalidNoMangleItems {
             hir::ItemKind::Impl(hir::Impl { generics, items, .. }) => {
                 for it in *items {
                     if let hir::AssocItemKind::Fn { .. } = it.kind {
-                        if let Some(no_mangle_attr) = cx
+                        if let Some(no_mangle_attr) =
-                            .sess()
+                            attr::find_by_name(cx.tcx.hir().attrs(it.id.hir_id()), sym::no_mangle)
-                            .find_by_name(cx.tcx.hir().attrs(it.id.hir_id()), sym::no_mangle)
                         {
                             check_no_mangle_on_generic_fn(
                                 no_mangle_attr,
@@ -1836,7 +1835,7 @@ impl<'tcx> LateLintPass<'tcx> for UnnameableTestItems {
         }
 
         let attrs = cx.tcx.hir().attrs(it.hir_id());
-        if let Some(attr) = cx.sess().find_by_name(attrs, sym::rustc_test_marker) {
+        if let Some(attr) = attr::find_by_name(attrs, sym::rustc_test_marker) {
             cx.emit_spanned_lint(UNNAMEABLE_TEST_ITEMS, attr.span, BuiltinUnnameableTestItems);
         }
     }

compiler/rustc_lint/src/nonstandard_style.rs

@@ -328,8 +328,7 @@ impl<'tcx> LateLintPass<'tcx> for NonSnakeCase {
         let crate_ident = if let Some(name) = &cx.tcx.sess.opts.crate_name {
             Some(Ident::from_str(name))
         } else {
-            cx.sess()
+            attr::find_by_name(&cx.tcx.hir().attrs(hir::CRATE_HIR_ID), sym::crate_name)
-                .find_by_name(&cx.tcx.hir().attrs(hir::CRATE_HIR_ID), sym::crate_name)
                 .and_then(|attr| attr.meta())
                 .and_then(|meta| {
                     meta.name_value_literal().and_then(|lit| {
@@ -489,7 +488,7 @@ impl<'tcx> LateLintPass<'tcx> for NonUpperCaseGlobals {
     fn check_item(&mut self, cx: &LateContext<'_>, it: &hir::Item<'_>) {
         let attrs = cx.tcx.hir().attrs(it.hir_id());
         match it.kind {
-            hir::ItemKind::Static(..) if !cx.sess().contains_name(attrs, sym::no_mangle) => {
+            hir::ItemKind::Static(..) if !attr::contains_name(attrs, sym::no_mangle) => {
                 NonUpperCaseGlobals::check_upper_case(cx, "static variable", &it.ident);
             }
             hir::ItemKind::Const(..) => {

compiler/rustc_metadata/src/creader.rs

@@ -687,8 +687,7 @@ impl<'a, 'tcx> CrateLoader<'a, 'tcx> {
         // compilation mode also comes into play.
         let desired_strategy = self.sess.panic_strategy();
         let mut runtime_found = false;
-        let mut needs_panic_runtime =
+        let mut needs_panic_runtime = attr::contains_name(&krate.attrs, sym::needs_panic_runtime);
-            self.sess.contains_name(&krate.attrs, sym::needs_panic_runtime);
 
         for (cnum, data) in self.cstore.iter_crate_data() {
             needs_panic_runtime = needs_panic_runtime || data.needs_panic_runtime();
@@ -756,7 +755,7 @@ impl<'a, 'tcx> CrateLoader<'a, 'tcx> {
         info!("loading profiler");
 
         let name = Symbol::intern(&self.sess.opts.unstable_opts.profiler_runtime);
-        if name == sym::profiler_builtins && self.sess.contains_name(&krate.attrs, sym::no_core) {
+        if name == sym::profiler_builtins && attr::contains_name(&krate.attrs, sym::no_core) {
             self.sess.emit_err(errors::ProfilerBuiltinsNeedsCore);
         }
 
@@ -770,14 +769,14 @@ impl<'a, 'tcx> CrateLoader<'a, 'tcx> {
     }
 
     fn inject_allocator_crate(&mut self, krate: &ast::Crate) {
-        self.cstore.has_global_allocator = match &*global_allocator_spans(&self.sess, krate) {
+        self.cstore.has_global_allocator = match &*global_allocator_spans(krate) {
             [span1, span2, ..] => {
                 self.sess.emit_err(errors::NoMultipleGlobalAlloc { span2: *span2, span1: *span1 });
                 true
             }
             spans => !spans.is_empty(),
         };
-        self.cstore.has_alloc_error_handler = match &*alloc_error_handler_spans(&self.sess, krate) {
+        self.cstore.has_alloc_error_handler = match &*alloc_error_handler_spans(krate) {
             [span1, span2, ..] => {
                 self.sess
                     .emit_err(errors::NoMultipleAllocErrorHandler { span2: *span2, span1: *span1 });
@@ -789,7 +788,7 @@ impl<'a, 'tcx> CrateLoader<'a, 'tcx> {
         // Check to see if we actually need an allocator. This desire comes
         // about through the `#![needs_allocator]` attribute and is typically
         // written down in liballoc.
-        if !self.sess.contains_name(&krate.attrs, sym::needs_allocator)
+        if !attr::contains_name(&krate.attrs, sym::needs_allocator)
             && !self.cstore.iter_crate_data().any(|(_, data)| data.needs_allocator())
         {
             return;
@@ -848,7 +847,7 @@ impl<'a, 'tcx> CrateLoader<'a, 'tcx> {
             // allocator. At this point our allocator request is typically fulfilled
             // by the standard library, denoted by the `#![default_lib_allocator]`
             // attribute.
-            if !self.sess.contains_name(&krate.attrs, sym::default_lib_allocator)
+            if !attr::contains_name(&krate.attrs, sym::default_lib_allocator)
                 && !self.cstore.iter_crate_data().any(|(_, data)| data.has_default_lib_allocator())
             {
                 self.sess.emit_err(errors::GlobalAllocRequired);
@@ -970,7 +969,7 @@ impl<'a, 'tcx> CrateLoader<'a, 'tcx> {
                     }
                     None => item.ident.name,
                 };
-                let dep_kind = if self.sess.contains_name(&item.attrs, sym::no_link) {
+                let dep_kind = if attr::contains_name(&item.attrs, sym::no_link) {
                     CrateDepKind::MacrosOnly
                 } else {
                     CrateDepKind::Explicit
@@ -1016,16 +1015,15 @@ impl<'a, 'tcx> CrateLoader<'a, 'tcx> {
     }
 }
 
-fn global_allocator_spans(sess: &Session, krate: &ast::Crate) -> Vec<Span> {
+fn global_allocator_spans(krate: &ast::Crate) -> Vec<Span> {
-    struct Finder<'a> {
+    struct Finder {
-        sess: &'a Session,
         name: Symbol,
         spans: Vec<Span>,
     }
-    impl<'ast, 'a> visit::Visitor<'ast> for Finder<'a> {
+    impl<'ast> visit::Visitor<'ast> for Finder {
         fn visit_item(&mut self, item: &'ast ast::Item) {
             if item.ident.name == self.name
-                && self.sess.contains_name(&item.attrs, sym::rustc_std_internal_symbol)
+                && attr::contains_name(&item.attrs, sym::rustc_std_internal_symbol)
             {
                 self.spans.push(item.span);
             }
@@ -1034,21 +1032,20 @@ fn global_allocator_spans(sess: &Session, krate: &ast::Crate) -> Vec<Span> {
     }
 
     let name = Symbol::intern(&AllocatorKind::Global.fn_name(sym::alloc));
-    let mut f = Finder { sess, name, spans: Vec::new() };
+    let mut f = Finder { name, spans: Vec::new() };
     visit::walk_crate(&mut f, krate);
     f.spans
 }
 
-fn alloc_error_handler_spans(sess: &Session, krate: &ast::Crate) -> Vec<Span> {
+fn alloc_error_handler_spans(krate: &ast::Crate) -> Vec<Span> {
-    struct Finder<'a> {
+    struct Finder {
-        sess: &'a Session,
         name: Symbol,
         spans: Vec<Span>,
     }
-    impl<'ast, 'a> visit::Visitor<'ast> for Finder<'a> {
+    impl<'ast> visit::Visitor<'ast> for Finder {
         fn visit_item(&mut self, item: &'ast ast::Item) {
             if item.ident.name == self.name
-                && self.sess.contains_name(&item.attrs, sym::rustc_std_internal_symbol)
+                && attr::contains_name(&item.attrs, sym::rustc_std_internal_symbol)
             {
                 self.spans.push(item.span);
             }
@@ -1057,7 +1054,7 @@ fn alloc_error_handler_spans(sess: &Session, krate: &ast::Crate) -> Vec<Span> {
     }
 
     let name = Symbol::intern(&AllocatorKind::Global.fn_name(sym::oom));
-    let mut f = Finder { sess, name, spans: Vec::new() };
+    let mut f = Finder { name, spans: Vec::new() };
     visit::walk_crate(&mut f, krate);
     f.spans
 }

compiler/rustc_metadata/src/rmeta/encoder.rs

@@ -681,17 +681,15 @@ impl<'a, 'tcx> EncodeContext<'a, 'tcx> {
                 has_global_allocator: tcx.has_global_allocator(LOCAL_CRATE),
                 has_alloc_error_handler: tcx.has_alloc_error_handler(LOCAL_CRATE),
                 has_panic_handler: tcx.has_panic_handler(LOCAL_CRATE),
-                has_default_lib_allocator: tcx
+                has_default_lib_allocator: attr::contains_name(&attrs, sym::default_lib_allocator),
-                    .sess
-                    .contains_name(&attrs, sym::default_lib_allocator),
                 proc_macro_data,
                 debugger_visualizers,
-                compiler_builtins: tcx.sess.contains_name(&attrs, sym::compiler_builtins),
+                compiler_builtins: attr::contains_name(&attrs, sym::compiler_builtins),
-                needs_allocator: tcx.sess.contains_name(&attrs, sym::needs_allocator),
+                needs_allocator: attr::contains_name(&attrs, sym::needs_allocator),
-                needs_panic_runtime: tcx.sess.contains_name(&attrs, sym::needs_panic_runtime),
+                needs_panic_runtime: attr::contains_name(&attrs, sym::needs_panic_runtime),
-                no_builtins: tcx.sess.contains_name(&attrs, sym::no_builtins),
+                no_builtins: attr::contains_name(&attrs, sym::no_builtins),
-                panic_runtime: tcx.sess.contains_name(&attrs, sym::panic_runtime),
+                panic_runtime: attr::contains_name(&attrs, sym::panic_runtime),
-                profiler_runtime: tcx.sess.contains_name(&attrs, sym::profiler_runtime),
+                profiler_runtime: attr::contains_name(&attrs, sym::profiler_runtime),
                 symbol_mangling_version: tcx.sess.opts.get_symbol_mangling_version(),
 
                 crate_deps,
@@ -1747,11 +1745,11 @@ impl<'a, 'tcx> EncodeContext<'a, 'tcx> {
                 // Proc-macros may have attributes like `#[allow_internal_unstable]`,
                 // so downstream crates need access to them.
                 let attrs = hir.attrs(proc_macro);
-                let macro_kind = if tcx.sess.contains_name(attrs, sym::proc_macro) {
+                let macro_kind = if attr::contains_name(attrs, sym::proc_macro) {
                     MacroKind::Bang
-                } else if tcx.sess.contains_name(attrs, sym::proc_macro_attribute) {
+                } else if attr::contains_name(attrs, sym::proc_macro_attribute) {
                     MacroKind::Attr
-                } else if let Some(attr) = tcx.sess.find_by_name(attrs, sym::proc_macro_derive) {
+                } else if let Some(attr) = attr::find_by_name(attrs, sym::proc_macro_derive) {
                     // This unwrap chain should have been checked by the proc-macro harness.
                     name = attr.meta_item_list().unwrap()[0]
                         .meta_item()

compiler/rustc_middle/src/ty/context.rs

@@ -28,7 +28,7 @@ use crate::ty::{
     TraitObjectVisitor, Ty, TyKind, TyVar, TyVid, TypeAndMut, TypeckResults, UintTy, Visibility,
 };
 use crate::ty::{GenericArg, InternalSubsts, SubstsRef};
-use rustc_ast as ast;
+use rustc_ast::{self as ast, attr};
 use rustc_data_structures::fingerprint::Fingerprint;
 use rustc_data_structures::fx::{FxHashMap, FxHashSet};
 use rustc_data_structures::intern::Interned;
@@ -2520,9 +2520,9 @@ pub fn provide(providers: &mut ty::query::Providers) {
     providers.extern_mod_stmt_cnum =
         |tcx, id| tcx.resolutions(()).extern_crate_map.get(&id).cloned();
     providers.is_panic_runtime =
-        |tcx, LocalCrate| tcx.sess.contains_name(tcx.hir().krate_attrs(), sym::panic_runtime);
+        |tcx, LocalCrate| attr::contains_name(tcx.hir().krate_attrs(), sym::panic_runtime);
     providers.is_compiler_builtins =
-        |tcx, LocalCrate| tcx.sess.contains_name(tcx.hir().krate_attrs(), sym::compiler_builtins);
+        |tcx, LocalCrate| attr::contains_name(tcx.hir().krate_attrs(), sym::compiler_builtins);
     providers.has_panic_handler = |tcx, LocalCrate| {
         // We want to check if the panic handler was defined in this crate
         tcx.lang_items().panic_impl().map_or(false, |did| did.is_local())

compiler/rustc_mir_build/src/build/mod.rs

@@ -3,6 +3,7 @@ use crate::build::expr::as_place::PlaceBuilder;
 use crate::build::scope::DropKind;
 use rustc_apfloat::ieee::{Double, Single};
 use rustc_apfloat::Float;
+use rustc_ast::attr;
 use rustc_data_structures::fx::FxHashMap;
 use rustc_data_structures::sorted_map::SortedIndexMultiMap;
 use rustc_errors::ErrorGuaranteed;
@@ -680,7 +681,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> {
         // Some functions always have overflow checks enabled,
         // however, they may not get codegen'd, depending on
         // the settings for the crate they are codegened in.
-        let mut check_overflow = tcx.sess.contains_name(attrs, sym::rustc_inherit_overflow_checks);
+        let mut check_overflow = attr::contains_name(attrs, sym::rustc_inherit_overflow_checks);
         // Respect -C overflow-checks.
         check_overflow |= tcx.sess.overflow_checks();
         // Constants always need overflow checks.

compiler/rustc_passes/src/check_attr.rs

@@ -1907,7 +1907,7 @@ impl CheckAttrVisitor<'_> {
         match target {
             Target::Fn => {
                 for attr in attrs {
-                    if self.tcx.sess.is_proc_macro_attr(attr) {
+                    if attr.is_proc_macro_attr() {
                         debug!("Is proc macro attr");
                         return true;
                     }

compiler/rustc_passes/src/entry.rs

@@ -1,3 +1,4 @@
+use rustc_ast::attr;
 use rustc_ast::entry::EntryPointType;
 use rustc_errors::error_code;
 use rustc_hir::def::DefKind;
@@ -37,7 +38,7 @@ fn entry_fn(tcx: TyCtxt<'_>, (): ()) -> Option<(DefId, EntryFnType)> {
     }
 
     // If the user wants no main function at all, then stop here.
-    if tcx.sess.contains_name(&tcx.hir().attrs(CRATE_HIR_ID), sym::no_main) {
+    if attr::contains_name(&tcx.hir().attrs(CRATE_HIR_ID), sym::no_main) {
         return None;
     }
 
@@ -57,9 +58,9 @@ fn entry_fn(tcx: TyCtxt<'_>, (): ()) -> Option<(DefId, EntryFnType)> {
 // An equivalent optimization was not applied to the duplicated code in test_harness.rs.
 fn entry_point_type(ctxt: &EntryContext<'_>, id: ItemId, at_root: bool) -> EntryPointType {
     let attrs = ctxt.tcx.hir().attrs(id.hir_id());
-    if ctxt.tcx.sess.contains_name(attrs, sym::start) {
+    if attr::contains_name(attrs, sym::start) {
         EntryPointType::Start
-    } else if ctxt.tcx.sess.contains_name(attrs, sym::rustc_main) {
+    } else if attr::contains_name(attrs, sym::rustc_main) {
         EntryPointType::RustcMainAttr
     } else {
         if let Some(name) = ctxt.tcx.opt_item_name(id.owner_id.to_def_id())
@@ -78,7 +79,7 @@ fn entry_point_type(ctxt: &EntryContext<'_>, id: ItemId, at_root: bool) -> Entry
 
 fn attr_span_by_symbol(ctxt: &EntryContext<'_>, id: ItemId, sym: Symbol) -> Option<Span> {
     let attrs = ctxt.tcx.hir().attrs(id.hir_id());
-    ctxt.tcx.sess.find_by_name(attrs, sym).map(|attr| attr.span)
+    attr::find_by_name(attrs, sym).map(|attr| attr.span)
 }
 
 fn find_item(id: ItemId, ctxt: &mut EntryContext<'_>) {

compiler/rustc_resolve/src/build_reduced_graph.rs

@@ -570,7 +570,7 @@ impl<'a, 'b, 'tcx> BuildReducedGraphVisitor<'a, 'b, 'tcx> {
             }
             ast::UseTreeKind::Glob => {
                 let kind = ImportKind::Glob {
-                    is_prelude: self.r.tcx.sess.contains_name(&item.attrs, sym::prelude_import),
+                    is_prelude: attr::contains_name(&item.attrs, sym::prelude_import),
                     max_vis: Cell::new(None),
                     id,
                 };
@@ -685,7 +685,7 @@ impl<'a, 'b, 'tcx> BuildReducedGraphVisitor<'a, 'b, 'tcx> {
                     expansion.to_expn_id(),
                     item.span,
                     parent.no_implicit_prelude
-                        || self.r.tcx.sess.contains_name(&item.attrs, sym::no_implicit_prelude),
+                        || attr::contains_name(&item.attrs, sym::no_implicit_prelude),
                 );
                 self.r.define(parent, ident, TypeNS, (module, vis, sp, expansion));
 
@@ -750,7 +750,7 @@ impl<'a, 'b, 'tcx> BuildReducedGraphVisitor<'a, 'b, 'tcx> {
                     // If the structure is marked as non_exhaustive then lower the visibility
                     // to within the crate.
                     let mut ctor_vis = if vis.is_public()
-                        && self.r.tcx.sess.contains_name(&item.attrs, sym::non_exhaustive)
+                        && attr::contains_name(&item.attrs, sym::non_exhaustive)
                     {
                         ty::Visibility::Restricted(CRATE_DEF_ID)
                     } else {
@@ -1168,12 +1168,11 @@ impl<'a, 'b, 'tcx> BuildReducedGraphVisitor<'a, 'b, 'tcx> {
     }
 
     fn proc_macro_stub(&self, item: &ast::Item) -> Option<(MacroKind, Ident, Span)> {
-        if self.r.tcx.sess.contains_name(&item.attrs, sym::proc_macro) {
+        if attr::contains_name(&item.attrs, sym::proc_macro) {
             return Some((MacroKind::Bang, item.ident, item.span));
-        } else if self.r.tcx.sess.contains_name(&item.attrs, sym::proc_macro_attribute) {
+        } else if attr::contains_name(&item.attrs, sym::proc_macro_attribute) {
             return Some((MacroKind::Attr, item.ident, item.span));
-        } else if let Some(attr) = self.r.tcx.sess.find_by_name(&item.attrs, sym::proc_macro_derive)
+        } else if let Some(attr) = attr::find_by_name(&item.attrs, sym::proc_macro_derive) {
-        {
             if let Some(nested_meta) = attr.meta_item_list().and_then(|list| list.get(0).cloned()) {
                 if let Some(ident) = nested_meta.ident() {
                     return Some((MacroKind::Derive, ident, ident.span));
@@ -1228,7 +1227,7 @@ impl<'a, 'b, 'tcx> BuildReducedGraphVisitor<'a, 'b, 'tcx> {
         if macro_rules {
             let ident = ident.normalize_to_macros_2_0();
             self.r.macro_names.insert(ident);
-            let is_macro_export = self.r.tcx.sess.contains_name(&item.attrs, sym::macro_export);
+            let is_macro_export = attr::contains_name(&item.attrs, sym::macro_export);
             let vis = if is_macro_export {
                 ty::Visibility::Public
             } else {
@@ -1488,13 +1487,12 @@ impl<'a, 'b, 'tcx> Visitor<'b> for BuildReducedGraphVisitor<'a, 'b, 'tcx> {
         self.r.visibilities.insert(def_id, vis);
 
         // If the variant is marked as non_exhaustive then lower the visibility to within the crate.
-        let ctor_vis = if vis.is_public()
+        let ctor_vis =
-            && self.r.tcx.sess.contains_name(&variant.attrs, sym::non_exhaustive)
+            if vis.is_public() && attr::contains_name(&variant.attrs, sym::non_exhaustive) {
-        {
+                ty::Visibility::Restricted(CRATE_DEF_ID)
-            ty::Visibility::Restricted(CRATE_DEF_ID)
+            } else {
-        } else {
+                vis
-            vis
+            };
-        };
 
         // Define a constructor name in the value namespace.
         if let Some((ctor_kind, ctor_node_id)) = CtorKind::from_ast(&variant.data) {

compiler/rustc_resolve/src/lib.rs

@@ -23,7 +23,7 @@ extern crate tracing;
 
 use rustc_arena::{DroplessArena, TypedArena};
 use rustc_ast::node_id::NodeMap;
-use rustc_ast::{self as ast, NodeId, CRATE_NODE_ID};
+use rustc_ast::{self as ast, attr, NodeId, CRATE_NODE_ID};
 use rustc_ast::{AngleBracketedArg, Crate, Expr, ExprKind, GenericArg, GenericArgs, LitKind, Path};
 use rustc_data_structures::fx::{FxHashMap, FxHashSet, FxIndexMap, FxIndexSet};
 use rustc_data_structures::intern::Interned;
@@ -1190,7 +1190,7 @@ impl<'a, 'tcx> Resolver<'a, 'tcx> {
             ModuleKind::Def(DefKind::Mod, root_def_id, kw::Empty),
             ExpnId::root(),
             krate.spans.inner_span,
-            tcx.sess.contains_name(&krate.attrs, sym::no_implicit_prelude),
+            attr::contains_name(&krate.attrs, sym::no_implicit_prelude),
             &mut module_map,
         );
         let empty_module = arenas.new_module(
@@ -1222,9 +1222,9 @@ impl<'a, 'tcx> Resolver<'a, 'tcx> {
             .map(|(name, _)| (Ident::from_str(name), Default::default()))
             .collect();
 
-        if !tcx.sess.contains_name(&krate.attrs, sym::no_core) {
+        if !attr::contains_name(&krate.attrs, sym::no_core) {
             extern_prelude.insert(Ident::with_dummy_span(sym::core), Default::default());
-            if !tcx.sess.contains_name(&krate.attrs, sym::no_std) {
+            if !attr::contains_name(&krate.attrs, sym::no_std) {
                 extern_prelude.insert(Ident::with_dummy_span(sym::std), Default::default());
             }
         }

compiler/rustc_resolve/src/macros.rs

@@ -5,7 +5,7 @@ use crate::Namespace::*;
 use crate::{BuiltinMacroState, Determinacy};
 use crate::{DeriveData, Finalize, ParentScope, ResolutionError, Resolver, ScopeSet};
 use crate::{ModuleKind, ModuleOrUniformRoot, NameBinding, PathResult, Segment};
-use rustc_ast::{self as ast, Inline, ItemKind, ModKind, NodeId};
+use rustc_ast::{self as ast, attr, Inline, ItemKind, ModKind, NodeId};
 use rustc_ast_pretty::pprust;
 use rustc_attr::StabilityLevel;
 use rustc_data_structures::intern::Interned;
@@ -113,7 +113,7 @@ fn fast_print_path(path: &ast::Path) -> Symbol {
 pub(crate) fn registered_tools(tcx: TyCtxt<'_>, (): ()) -> RegisteredTools {
     let mut registered_tools = RegisteredTools::default();
     let krate = tcx.crate_for_resolver(()).borrow();
-    for attr in tcx.sess.filter_by_name(&krate.attrs, sym::register_tool) {
+    for attr in attr::filter_by_name(&krate.attrs, sym::register_tool) {
         for nested_meta in attr.meta_item_list().unwrap_or_default() {
             match nested_meta.ident() {
                 Some(ident) => {

compiler/rustc_session/src/output.rs

@@ -5,7 +5,7 @@ use crate::errors::{
     InvalidCharacterInCrateName,
 };
 use crate::Session;
-use rustc_ast as ast;
+use rustc_ast::{self as ast, attr};
 use rustc_span::symbol::sym;
 use rustc_span::{Span, Symbol};
 use std::path::{Path, PathBuf};
@@ -56,7 +56,7 @@ pub fn find_crate_name(sess: &Session, attrs: &[ast::Attribute]) -> Symbol {
     // the command line over one found in the #[crate_name] attribute. If we
     // find both we ensure that they're the same later on as well.
     let attr_crate_name =
-        sess.find_by_name(attrs, sym::crate_name).and_then(|at| at.value_str().map(|s| (at, s)));
+        attr::find_by_name(attrs, sym::crate_name).and_then(|at| at.value_str().map(|s| (at, s)));
 
     if let Some(ref s) = sess.opts.crate_name {
         let s = Symbol::intern(s);

compiler/rustc_session/src/session.rs

@@ -30,7 +30,7 @@ use rustc_macros::HashStable_Generic;
 pub use rustc_span::def_id::StableCrateId;
 use rustc_span::edition::Edition;
 use rustc_span::source_map::{FileLoader, RealFileLoader, SourceMap, Span};
-use rustc_span::{sym, SourceFileHashAlgorithm, Symbol};
+use rustc_span::{SourceFileHashAlgorithm, Symbol};
 use rustc_target::asm::InlineAsmArch;
 use rustc_target::spec::{CodeModel, PanicStrategy, RelocModel, RelroLevel};
 use rustc_target::spec::{
@@ -1003,40 +1003,6 @@ impl Session {
         || self.opts.unstable_opts.sanitizer.intersects(SanitizerSet::ADDRESS | SanitizerSet::KERNELADDRESS | SanitizerSet::MEMORY | SanitizerSet::HWADDRESS)
     }
 
-    pub fn is_proc_macro_attr(&self, attr: &Attribute) -> bool {
-        [sym::proc_macro, sym::proc_macro_attribute, sym::proc_macro_derive]
-            .iter()
-            .any(|kind| attr.has_name(*kind))
-    }
-
-    pub fn contains_name(&self, attrs: &[Attribute], name: Symbol) -> bool {
-        attrs.iter().any(|item| item.has_name(name))
-    }
-
-    pub fn find_by_name<'a>(
-        &'a self,
-        attrs: &'a [Attribute],
-        name: Symbol,
-    ) -> Option<&'a Attribute> {
-        attrs.iter().find(|attr| attr.has_name(name))
-    }
-
-    pub fn filter_by_name<'a>(
-        &'a self,
-        attrs: &'a [Attribute],
-        name: Symbol,
-    ) -> impl Iterator<Item = &'a Attribute> {
-        attrs.iter().filter(move |attr| attr.has_name(name))
-    }
-
-    pub fn first_attr_value_str_by_name(
-        &self,
-        attrs: &[Attribute],
-        name: Symbol,
-    ) -> Option<Symbol> {
-        attrs.iter().find(|at| at.has_name(name)).and_then(|at| at.value_str())
-    }
-
     pub fn diagnostic_width(&self) -> usize {
         let default_column_width = 140;
         if let Some(width) = self.opts.diagnostic_width {

src/tools/clippy/clippy_lints/src/functions/must_use.rs

@@ -28,7 +28,7 @@ pub(super) fn check_item<'tcx>(cx: &LateContext<'tcx>, item: &'tcx hir::Item<'_>
         let fn_header_span = item.span.with_hi(sig.decl.output.span().hi());
         if let Some(attr) = attr {
             check_needless_must_use(cx, sig.decl, item.owner_id, item.span, fn_header_span, attr);
-        } else if is_public && !is_proc_macro(cx.sess(), attrs) && !attrs.iter().any(|a| a.has_name(sym::no_mangle)) {
+        } else if is_public && !is_proc_macro(attrs) && !attrs.iter().any(|a| a.has_name(sym::no_mangle)) {
             check_must_use_candidate(
                 cx,
                 sig.decl,
@@ -51,7 +51,7 @@ pub(super) fn check_impl_item<'tcx>(cx: &LateContext<'tcx>, item: &'tcx hir::Imp
         if let Some(attr) = attr {
             check_needless_must_use(cx, sig.decl, item.owner_id, item.span, fn_header_span, attr);
         } else if is_public
-            && !is_proc_macro(cx.sess(), attrs)
+            && !is_proc_macro(attrs)
             && trait_ref_of_method(cx, item.owner_id.def_id).is_none()
         {
             check_must_use_candidate(
@@ -78,7 +78,7 @@ pub(super) fn check_trait_item<'tcx>(cx: &LateContext<'tcx>, item: &'tcx hir::Tr
             check_needless_must_use(cx, sig.decl, item.owner_id, item.span, fn_header_span, attr);
         } else if let hir::TraitFn::Provided(eid) = *eid {
             let body = cx.tcx.hir().body(eid);
-            if attr.is_none() && is_public && !is_proc_macro(cx.sess(), attrs) {
+            if attr.is_none() && is_public && !is_proc_macro(attrs) {
                 check_must_use_candidate(
                     cx,
                     sig.decl,

src/tools/clippy/clippy_utils/src/attrs.rs

@@ -145,8 +145,8 @@ pub fn get_unique_attr<'a>(
 
 /// Return true if the attributes contain any of `proc_macro`,
 /// `proc_macro_derive` or `proc_macro_attribute`, false otherwise
-pub fn is_proc_macro(sess: &Session, attrs: &[ast::Attribute]) -> bool {
+pub fn is_proc_macro(attrs: &[ast::Attribute]) -> bool {
-    attrs.iter().any(|attr| sess.is_proc_macro_attr(attr))
+    attrs.iter().any(|attr| attr.is_proc_macro_attr())
 }
 
 /// Return true if the attributes contain `#[doc(hidden)]`

src/tools/rustfmt/src/attr.rs

@@ -2,7 +2,7 @@
 
 use rustc_ast::ast;
 use rustc_ast::HasAttrs;
-use rustc_span::{symbol::sym, Span, Symbol};
+use rustc_span::{symbol::sym, Span};
 
 use self::doc_comment::DocCommentFormatter;
 use crate::comment::{contains_comment, rewrite_doc_comment, CommentStyle};
@@ -19,20 +19,6 @@ use crate::utils::{count_newlines, mk_sp};
 
 mod doc_comment;
 
-pub(crate) fn contains_name(attrs: &[ast::Attribute], name: Symbol) -> bool {
-    attrs.iter().any(|attr| attr.has_name(name))
-}
-
-pub(crate) fn first_attr_value_str_by_name(
-    attrs: &[ast::Attribute],
-    name: Symbol,
-) -> Option<Symbol> {
-    attrs
-        .iter()
-        .find(|attr| attr.has_name(name))
-        .and_then(|attr| attr.value_str())
-}
-
 /// Returns attributes on the given statement.
 pub(crate) fn get_attrs_from_stmt(stmt: &ast::Stmt) -> &[ast::Attribute] {
     stmt.attrs()

src/tools/rustfmt/src/parse/parser.rs

@@ -2,13 +2,12 @@ use std::panic::{catch_unwind, AssertUnwindSafe};
 use std::path::{Path, PathBuf};
 
 use rustc_ast::token::TokenKind;
-use rustc_ast::{ast, ptr};
+use rustc_ast::{ast, attr, ptr};
 use rustc_errors::Diagnostic;
 use rustc_parse::{new_parser_from_file, parser::Parser as RawParser};
 use rustc_span::{sym, Span};
 use thin_vec::ThinVec;
 
-use crate::attr::first_attr_value_str_by_name;
 use crate::parse::session::ParseSess;
 use crate::Input;
 
@@ -93,7 +92,7 @@ pub(crate) enum ParserError {
 
 impl<'a> Parser<'a> {
     pub(crate) fn submod_path_from_attr(attrs: &[ast::Attribute], path: &Path) -> Option<PathBuf> {
-        let path_sym = first_attr_value_str_by_name(attrs, sym::path)?;
+        let path_sym = attr::first_attr_value_str_by_name(attrs, sym::path)?;
         let path_str = path_sym.as_str();
 
         // On windows, the base path might have the form

src/tools/rustfmt/src/reorder.rs

@@ -8,7 +8,7 @@
 
 use std::cmp::{Ord, Ordering};
 
-use rustc_ast::ast;
+use rustc_ast::{ast, attr};
 use rustc_span::{symbol::sym, Span};
 
 use crate::config::{Config, GroupImportsTactic};
@@ -167,7 +167,7 @@ fn rewrite_reorderable_or_regroupable_items(
 }
 
 fn contains_macro_use_attr(item: &ast::Item) -> bool {
-    crate::attr::contains_name(&item.attrs, sym::macro_use)
+    attr::contains_name(&item.attrs, sym::macro_use)
 }
 
 /// Divides imports into three groups, corresponding to standard, external

tests/ui-fulldeps/auxiliary/lint-for-crate-rpass.rs

@@ -1,80 +0,0 @@
-// force-host
-
-#![feature(rustc_private)]
-
-extern crate rustc_driver;
-extern crate rustc_hir;
-extern crate rustc_lint;
-extern crate rustc_span;
-#[macro_use]
-extern crate rustc_session;
-extern crate rustc_ast;
-
-use rustc_ast::attr;
-use rustc_driver::plugin::Registry;
-use rustc_lint::{LateContext, LateLintPass, LintContext, LintPass};
-use rustc_span::def_id::CRATE_DEF_ID;
-use rustc_span::symbol::Symbol;
-
-macro_rules! fake_lint_pass {
-    ($struct:ident, $($attr:expr),*) => {
-        struct $struct;
-
-        impl LintPass for $struct {
-            fn name(&self) -> &'static str {
-                stringify!($struct)
-            }
-        }
-
-        impl LateLintPass<'_> for $struct {
-            fn check_crate(&mut self, cx: &LateContext) {
-                let attrs = cx.tcx.hir().attrs(rustc_hir::CRATE_HIR_ID);
-                let span = cx.tcx.def_span(CRATE_DEF_ID);
-                $(
-                    if !cx.sess().contains_name(attrs, $attr) {
-                        cx.lint(CRATE_NOT_OKAY, |lint| {
-                             let msg = format!("crate is not marked with #![{}]", $attr);
-                             lint.build(&msg).set_span(span).emit();
-                        });
-                    }
-                )*
-            }
-        }
-
-    }
-}
-
-declare_lint!(CRATE_NOT_OKAY, Warn, "crate not marked with #![crate_okay]");
-declare_lint!(CRATE_NOT_RED, Warn, "crate not marked with #![crate_red]");
-declare_lint!(CRATE_NOT_BLUE, Warn, "crate not marked with #![crate_blue]");
-declare_lint!(CRATE_NOT_GREY, Warn, "crate not marked with #![crate_grey]");
-declare_lint!(CRATE_NOT_GREEN, Warn, "crate not marked with #![crate_green]");
-
-fake_lint_pass! {
-    PassOkay,
-    Symbol::intern("crate_okay")
-}
-
-fake_lint_pass! {
-    PassRedBlue,
-    Symbol::intern("crate_red"), Symbol::intern("crate_blue")
-}
-
-fake_lint_pass! {
-    PassGreyGreen,
-    Symbol::intern("crate_grey"), Symbol::intern("crate_green")
-}
-
-#[no_mangle]
-fn __rustc_plugin_registrar(reg: &mut Registry) {
-    reg.lint_store.register_lints(&[
-        &CRATE_NOT_OKAY,
-        &CRATE_NOT_RED,
-        &CRATE_NOT_BLUE,
-        &CRATE_NOT_GREY,
-        &CRATE_NOT_GREEN,
-    ]);
-    reg.lint_store.register_late_pass(|_| Box::new(PassOkay));
-    reg.lint_store.register_late_pass(|_| Box::new(PassRedBlue));
-    reg.lint_store.register_late_pass(|_| Box::new(PassGreyGreen));
-}

tests/ui-fulldeps/auxiliary/lint-for-crate.rs

@@ -4,13 +4,13 @@
 
 extern crate rustc_driver;
 extern crate rustc_hir;
-#[macro_use]
 extern crate rustc_lint;
 #[macro_use]
 extern crate rustc_session;
 extern crate rustc_ast;
 extern crate rustc_span;
 
+use rustc_ast::attr;
 use rustc_driver::plugin::Registry;
 use rustc_lint::{LateContext, LateLintPass, LintContext};
 use rustc_span::def_id::CRATE_DEF_ID;
@@ -28,12 +28,10 @@ impl<'tcx> LateLintPass<'tcx> for Pass {
     fn check_crate(&mut self, cx: &LateContext) {
         let attrs = cx.tcx.hir().attrs(rustc_hir::CRATE_HIR_ID);
         let span = cx.tcx.def_span(CRATE_DEF_ID);
-        if !cx.sess().contains_name(attrs, Symbol::intern("crate_okay")) {
+        if !attr::contains_name(attrs, Symbol::intern("crate_okay")) {
-            cx.lint(
+            cx.lint(CRATE_NOT_OKAY, "crate is not marked with #![crate_okay]", |lint| {
-                CRATE_NOT_OKAY,
+                lint.set_span(span)
-                "crate is not marked with #![crate_okay]",
+            });
-                |lint| lint.set_span(span)
-            );
         }
     }
 }