Auto merge of #56818 - kennytm:rollup-2, r=kennytm

Rollup of 14 pull requests (first batch)

Successful merges:

 - #56562 (Update libc version required by rustc)
 - #56609 (Unconditionally emit the target-cpu LLVM attribute.)
 - #56637 (rustdoc: Fix local reexports of proc macros)
 - #56658 (Add non-panicking `maybe_new_parser_from_file` variant)
 - #56695 (Fix irrefutable matches on integer ranges)
 - #56699 (Use a `newtype_index!` within `Symbol`.)
 - #56702 ([self-profiler] Add column for percent of total time)
 - #56708 (Remove some unnecessary feature gates)
 - #56709 (Remove unneeded extra chars to reduce search-index size)
 - #56744 (specialize: remove Boxes used by Children::insert)
 - #56748 (Update panic message to be clearer about env-vars)
 - #56749 (x86: Add the `adx` target feature to whitelist)
 - #56756 (Disable btree pretty-printers on older gdbs)
 - #56789 (rustc: Add an unstable `simd_select_bitmask` intrinsic)

r? @ghost

src/etc/gdb_rust_pretty_printing.py

@@ -9,6 +9,7 @@
 # except according to those terms.
 
 import gdb
+import re
 import sys
 import debugger_pretty_printers_common as rustpp
 
@@ -20,6 +21,16 @@
 
 rust_enabled = 'set language rust' in gdb.execute('complete set language ru', to_string = True)
 
+# The btree pretty-printers fail in a confusing way unless
+# https://sourceware.org/bugzilla/show_bug.cgi?id=21763 is fixed.
+# This fix went in 8.1, so check for that.
+# See https://github.com/rust-lang/rust/issues/56730
+gdb_81 = False
+_match = re.match('([0-9]+)\\.([0-9]+)', gdb.VERSION)
+if _match:
+    if int(_match.group(1)) > 8 or (int(_match.group(1)) == 8 and int(_match.group(2)) >= 1):
+        gdb_81 = True
+
 #===============================================================================
 # GDB Pretty Printing Module for Rust
 #===============================================================================
@@ -110,10 +121,10 @@ def rust_pretty_printer_lookup_function(gdb_val):
     if type_kind == rustpp.TYPE_KIND_STD_VECDEQUE:
         return RustStdVecDequePrinter(val)
 
-    if type_kind == rustpp.TYPE_KIND_STD_BTREESET:
+    if type_kind == rustpp.TYPE_KIND_STD_BTREESET and gdb_81:
         return RustStdBTreeSetPrinter(val)
 
-    if type_kind == rustpp.TYPE_KIND_STD_BTREEMAP:
+    if type_kind == rustpp.TYPE_KIND_STD_BTREEMAP and gdb_81:
         return RustStdBTreeMapPrinter(val)
 
     if type_kind == rustpp.TYPE_KIND_STD_STRING:

src/librustc/traits/specialize/specialization_graph.rs

@@ -132,10 +132,12 @@ impl<'a, 'gcx, 'tcx> Children {
             simplified_self,
         );
 
-        for possible_sibling in match simplified_self {
-            Some(sty) => self.filtered(sty),
-            None => self.iter(),
-        } {
+        let possible_siblings = match simplified_self {
+            Some(sty) => PotentialSiblings::Filtered(self.filtered(sty)),
+            None => PotentialSiblings::Unfiltered(self.iter()),
+        };
+
+        for possible_sibling in possible_siblings {
             debug!(
                 "insert: impl_def_id={:?}, simplified_self={:?}, possible_sibling={:?}",
                 impl_def_id,
@@ -222,14 +224,37 @@ impl<'a, 'gcx, 'tcx> Children {
         Ok(Inserted::BecameNewSibling(last_lint))
     }
 
-    fn iter(&mut self) -> Box<dyn Iterator<Item = DefId> + '_> {
+    fn iter(&mut self) -> impl Iterator<Item = DefId> + '_ {
         let nonblanket = self.nonblanket_impls.iter_mut().flat_map(|(_, v)| v.iter());
-        Box::new(self.blanket_impls.iter().chain(nonblanket).cloned())
+        self.blanket_impls.iter().chain(nonblanket).cloned()
     }
 
-    fn filtered(&mut self, sty: SimplifiedType) -> Box<dyn Iterator<Item = DefId> + '_> {
+    fn filtered(&mut self, sty: SimplifiedType) -> impl Iterator<Item = DefId> + '_ {
         let nonblanket = self.nonblanket_impls.entry(sty).or_default().iter();
-        Box::new(self.blanket_impls.iter().chain(nonblanket).cloned())
+        self.blanket_impls.iter().chain(nonblanket).cloned()
+    }
+}
+
+// A custom iterator used by Children::insert
+enum PotentialSiblings<I, J>
+    where I: Iterator<Item = DefId>,
+          J: Iterator<Item = DefId>
+{
+    Unfiltered(I),
+    Filtered(J)
+}
+
+impl<I, J> Iterator for PotentialSiblings<I, J>
+    where I: Iterator<Item = DefId>,
+          J: Iterator<Item = DefId>
+{
+    type Item = DefId;
+
+    fn next(&mut self) -> Option<Self::Item> {
+        match *self {
+            PotentialSiblings::Unfiltered(ref mut iter) => iter.next(),
+            PotentialSiblings::Filtered(ref mut iter) => iter.next()
+        }
     }
 }
 

src/librustc/util/profiling.rs

@@ -62,11 +62,15 @@ macro_rules! define_categories {
             }
 
             fn print(&self, lock: &mut StderrLock<'_>) {
-                writeln!(lock, "| Phase            | Time (ms)      | Queries        | Hits (%) |")
+                writeln!(lock, "| Phase            | Time (ms)      \
+                                | Time (%) | Queries        | Hits (%)")
                     .unwrap();
-                writeln!(lock, "| ---------------- | -------------- | -------------- | -------- |")
+                writeln!(lock, "| ---------------- | -------------- \
+                                | -------- | -------------- | --------")
                     .unwrap();
 
+                let total_time = ($(self.times.$name + )* 0) as f32;
+
                 $(
                     let (hits, total) = self.query_counts.$name;
                     let (hits, total) = if total > 0 {
@@ -78,11 +82,12 @@ macro_rules! define_categories {
 
                     writeln!(
                         lock,
-                        "| {0: <16} | {1: <14} | {2: <14} | {3: <8} |",
+                        "| {0: <16} | {1: <14} | {2: <8.2} | {3: <14} | {4: <8}",
                         stringify!($name),
                         self.times.$name / 1_000_000,
+                        ((self.times.$name as f32) / total_time) * 100.0,
                         total,
-                        hits
+                        hits,
                     ).unwrap();
                 )*
             }

src/librustc_codegen_llvm/attributes.rs

@@ -18,6 +18,7 @@ use rustc::session::config::Sanitizer;
 use rustc::ty::{self, TyCtxt, PolyFnSig};
 use rustc::ty::layout::HasTyCtxt;
 use rustc::ty::query::Providers;
+use rustc_data_structures::small_c_str::SmallCStr;
 use rustc_data_structures::sync::Lrc;
 use rustc_data_structures::fx::FxHashMap;
 use rustc_target::spec::PanicStrategy;
@@ -130,8 +131,7 @@ pub fn llvm_target_features(sess: &Session) -> impl Iterator<Item = &str> {
 }
 
 pub fn apply_target_cpu_attr(cx: &CodegenCx<'ll, '_>, llfn: &'ll Value) {
-    let cpu = llvm_util::target_cpu(cx.tcx.sess);
-    let target_cpu = CString::new(cpu).unwrap();
+    let target_cpu = SmallCStr::new(llvm_util::target_cpu(cx.tcx.sess));
     llvm::AddFunctionAttrStringValue(
             llfn,
             llvm::AttributePlace::Function,
@@ -231,11 +231,7 @@ pub fn from_fn_attrs(
     // Always annotate functions with the target-cpu they are compiled for.
     // Without this, ThinLTO won't inline Rust functions into Clang generated
     // functions (because Clang annotates functions this way too).
-    // NOTE: For now we just apply this if -Zcross-lang-lto is specified, since
-    //       it introduce a little overhead and isn't really necessary otherwise.
-    if cx.tcx.sess.opts.debugging_opts.cross_lang_lto.enabled() {
-        apply_target_cpu_attr(cx, llfn);
-    }
+    apply_target_cpu_attr(cx, llfn);
 
     let features = llvm_target_features(cx.tcx.sess)
         .map(|s| s.to_string())

src/librustc_codegen_llvm/intrinsic.rs

@@ -1171,6 +1171,27 @@ fn generic_simd_intrinsic(
     );
     let arg_tys = sig.inputs();
 
+    if name == "simd_select_bitmask" {
+        let in_ty = arg_tys[0];
+        let m_len = match in_ty.sty {
+            // Note that this `.unwrap()` crashes for isize/usize, that's sort
+            // of intentional as there's not currently a use case for that.
+            ty::Int(i) => i.bit_width().unwrap(),
+            ty::Uint(i) => i.bit_width().unwrap(),
+            _ => return_error!("`{}` is not an integral type", in_ty),
+        };
+        require_simd!(arg_tys[1], "argument");
+        let v_len = arg_tys[1].simd_size(tcx);
+        require!(m_len == v_len,
+                 "mismatched lengths: mask length `{}` != other vector length `{}`",
+                 m_len, v_len
+        );
+        let i1 = bx.type_i1();
+        let i1xn = bx.type_vector(i1, m_len as u64);
+        let m_i1s = bx.bitcast(args[0].immediate(), i1xn);
+        return Ok(bx.select(m_i1s, args[1].immediate(), args[2].immediate()));
+    }
+
     // every intrinsic takes a SIMD vector as its first argument
     require_simd!(arg_tys[0], "input");
     let in_ty = arg_tys[0];

src/librustc_codegen_llvm/llvm_util.rs

@@ -124,6 +124,7 @@ const AARCH64_WHITELIST: &[(&str, Option<&str>)] = &[
 ];
 
 const X86_WHITELIST: &[(&str, Option<&str>)] = &[
+    ("adx", Some("adx_target_feature")),
     ("aes", None),
     ("avx", None),
     ("avx2", None),

src/librustc_codegen_ssa/Cargo.toml

@@ -16,7 +16,7 @@ num_cpus = "1.0"
 rustc-demangle = "0.1.4"
 memmap = "0.6"
 log = "0.4.5"
-libc = "0.2.43"
+libc = "0.2.44"
 jobserver = "0.1.11"
 
 serialize = { path = "../libserialize" }

src/librustc_mir/build/matches/simplify.rs

@@ -26,6 +26,10 @@ use build::{BlockAnd, BlockAndExtension, Builder};
 use build::matches::{Ascription, Binding, MatchPair, Candidate};
 use hair::*;
 use rustc::mir::*;
+use rustc::ty;
+use rustc::ty::layout::{Integer, IntegerExt, Size};
+use syntax::attr::{SignedInt, UnsignedInt};
+use rustc::hir::RangeEnd;
 
 use std::mem;
 
@@ -62,6 +66,7 @@ impl<'a, 'gcx, 'tcx> Builder<'a, 'gcx, 'tcx> {
                                  match_pair: MatchPair<'pat, 'tcx>,
                                  candidate: &mut Candidate<'pat, 'tcx>)
                                  -> Result<(), MatchPair<'pat, 'tcx>> {
+        let tcx = self.hir.tcx();
         match *match_pair.pattern.kind {
             PatternKind::AscribeUserType { ref subpattern, ref user_ty, user_ty_span } => {
                 candidate.ascriptions.push(Ascription {
@@ -104,7 +109,34 @@ impl<'a, 'gcx, 'tcx> Builder<'a, 'gcx, 'tcx> {
                 Err(match_pair)
             }
 
-            PatternKind::Range { .. } => {
+            PatternKind::Range { lo, hi, ty, end } => {
+                let range = match ty.sty {
+                    ty::Char => {
+                        Some(('\u{0000}' as u128, '\u{10FFFF}' as u128, Size::from_bits(32)))
+                    }
+                    ty::Int(ity) => {
+                        // FIXME(49937): refactor these bit manipulations into interpret.
+                        let size = Integer::from_attr(&tcx, SignedInt(ity)).size();
+                        let min = 1u128 << (size.bits() - 1);
+                        let max = (1u128 << (size.bits() - 1)) - 1;
+                        Some((min, max, size))
+                    }
+                    ty::Uint(uty) => {
+                        // FIXME(49937): refactor these bit manipulations into interpret.
+                        let size = Integer::from_attr(&tcx, UnsignedInt(uty)).size();
+                        let max = !0u128 >> (128 - size.bits());
+                        Some((0, max, size))
+                    }
+                    _ => None,
+                };
+                if let Some((min, max, sz)) = range {
+                    if let (Some(lo), Some(hi)) = (lo.val.try_to_bits(sz), hi.val.try_to_bits(sz)) {
+                        if lo <= min && (hi > max || hi == max && end == RangeEnd::Included) {
+                            // Irrefutable pattern match.
+                            return Ok(());
+                        }
+                    }
+                }
                 Err(match_pair)
             }
 

src/librustc_typeck/check/intrinsic.rs

@@ -435,7 +435,8 @@ pub fn check_platform_intrinsic_type<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
         "simd_insert" => (2, vec![param(0), tcx.types.u32, param(1)], param(0)),
         "simd_extract" => (2, vec![param(0), tcx.types.u32], param(1)),
         "simd_cast" => (2, vec![param(0)], param(1)),
-        "simd_select" => (2, vec![param(0), param(1), param(1)], param(1)),
+        "simd_select" |
+        "simd_select_bitmask" => (2, vec![param(0), param(1), param(1)], param(1)),
         "simd_reduce_all" | "simd_reduce_any" => (1, vec![param(0)], tcx.types.bool),
         "simd_reduce_add_ordered" | "simd_reduce_mul_ordered"
             => (2, vec![param(0), param(1)], param(1)),

src/librustdoc/html/markdown.rs

@@ -806,6 +806,10 @@ impl<'a> fmt::Display for MarkdownSummaryLine<'a> {
 }
 
 pub fn plain_summary_line(md: &str) -> String {
+    plain_summary_line_full(md, false)
+}
+
+pub fn plain_summary_line_full(md: &str, limit_length: bool) -> String {
     struct ParserWrapper<'a> {
         inner: Parser<'a>,
         is_in: isize,
@@ -852,7 +856,21 @@ pub fn plain_summary_line(md: &str) -> String {
             s.push_str(&t);
         }
     }
-    s
+    if limit_length && s.chars().count() > 60 {
+        let mut len = 0;
+        let mut ret = s.split_whitespace()
+                       .take_while(|p| {
+                           // + 1 for the added character after the word.
+                           len += p.chars().count() + 1;
+                           len < 60
+                       })
+                       .collect::<Vec<_>>()
+                       .join(" ");
+        ret.push('…');
+        ret
+    } else {
+        s
+    }
 }
 
 pub fn markdown_links(md: &str) -> Vec<(String, Option<Range<usize>>)> {

src/librustdoc/html/render.rs

@@ -698,7 +698,7 @@ fn build_index(krate: &clean::Crate, cache: &mut Cache) -> String {
                 ty: item.type_(),
                 name: item.name.clone().unwrap(),
                 path: fqp[..fqp.len() - 1].join("::"),
-                desc: plain_summary_line(item.doc_value()),
+                desc: plain_summary_line_short(item.doc_value()),
                 parent: Some(did),
                 parent_idx: None,
                 search_type: get_index_search_type(&item),
@@ -736,7 +736,7 @@ fn build_index(krate: &clean::Crate, cache: &mut Cache) -> String {
     }
 
     let crate_doc = krate.module.as_ref().map(|module| {
-        plain_summary_line(module.doc_value())
+        plain_summary_line_short(module.doc_value())
     }).unwrap_or(String::new());
 
     let mut crate_data = BTreeMap::new();
@@ -1481,7 +1481,7 @@ impl DocFolder for Cache {
                             ty: item.type_(),
                             name: s.to_string(),
                             path: path.join("::"),
-                            desc: plain_summary_line(item.doc_value()),
+                            desc: plain_summary_line_short(item.doc_value()),
                             parent,
                             parent_idx: None,
                             search_type: get_index_search_type(&item),
@@ -1512,7 +1512,8 @@ impl DocFolder for Cache {
             clean::FunctionItem(..) | clean::ModuleItem(..) |
             clean::ForeignFunctionItem(..) | clean::ForeignStaticItem(..) |
             clean::ConstantItem(..) | clean::StaticItem(..) |
-            clean::UnionItem(..) | clean::ForeignTypeItem | clean::MacroItem(..)
+            clean::UnionItem(..) | clean::ForeignTypeItem |
+            clean::MacroItem(..) | clean::ProcMacroItem(..)
             if !self.stripped_mod => {
                 // Re-exported items mean that the same id can show up twice
                 // in the rustdoc ast that we're looking at. We know,
@@ -1673,7 +1674,7 @@ impl<'a> Cache {
                                 ty: item.type_(),
                                 name: item_name.to_string(),
                                 path: path.clone(),
-                                desc: plain_summary_line(item.doc_value()),
+                                desc: plain_summary_line_short(item.doc_value()),
                                 parent: None,
                                 parent_idx: None,
                                 search_type: get_index_search_type(&item),
@@ -2388,7 +2389,13 @@ fn shorter<'a>(s: Option<&'a str>) -> String {
 #[inline]
 fn plain_summary_line(s: Option<&str>) -> String {
     let line = shorter(s).replace("\n", " ");
-    markdown::plain_summary_line(&line[..])
+    markdown::plain_summary_line_full(&line[..], false)
+}
+
+#[inline]
+fn plain_summary_line_short(s: Option<&str>) -> String {
+    let line = shorter(s).replace("\n", " ");
+    markdown::plain_summary_line_full(&line[..], true)
 }
 
 fn document(w: &mut fmt::Formatter, cx: &Context, item: &clean::Item) -> fmt::Result {

src/librustdoc/visit_ast.rs

@@ -424,10 +424,11 @@ impl<'a, 'tcx, 'rcx, 'cstore> RustdocVisitor<'a, 'tcx, 'rcx, 'cstore> {
             hir::ItemKind::Use(ref path, kind) => {
                 let is_glob = kind == hir::UseKind::Glob;
 
-                // Struct and variant constructors always show up alongside their definitions, we've
-                // already processed them so just discard these.
+                // Struct and variant constructors and proc macro stubs always show up alongside
+                // their definitions, we've already processed them so just discard these.
                 match path.def {
-                    Def::StructCtor(..) | Def::VariantCtor(..) | Def::SelfCtor(..) => return,
+                    Def::StructCtor(..) | Def::VariantCtor(..) | Def::SelfCtor(..) |
+                    Def::Macro(_, MacroKind::ProcMacroStub) => return,
                     _ => {}
                 }
 

src/libstd/io/lazy.rs

@@ -26,7 +26,6 @@ const fn done<T>() -> *mut Arc<T> { 1_usize as *mut _ }
 unsafe impl<T> Sync for Lazy<T> {}
 
 impl<T> Lazy<T> {
-    #[unstable(feature = "sys_internals", issue = "0")] // FIXME: min_const_fn
     pub const fn new() -> Lazy<T> {
         Lazy {
             lock: Mutex::new(),

src/libstd/lib.rs

@@ -271,6 +271,7 @@
 #![feature(libc)]
 #![feature(link_args)]
 #![feature(linkage)]
+#![cfg_attr(not(stage0), feature(min_const_unsafe_fn))]
 #![feature(needs_panic_runtime)]
 #![feature(never_type)]
 #![feature(nll)]