Rollup of 9 pull requests

compiler/rustc_codegen_llvm/src/llvm_util.rs

@@ -180,6 +180,7 @@ pub fn to_llvm_feature<'a>(sess: &Session, s: &'a str) -> Vec<&'a str> {
         ("aarch64", "dpb2") => vec!["ccdp"],
         ("aarch64", "frintts") => vec!["fptoint"],
         ("aarch64", "fcma") => vec!["complxnum"],
+        ("aarch64", "pmuv3") => vec!["perfmon"],
         (_, s) => vec![s],
     }
 }

compiler/rustc_codegen_ssa/src/target_features.rs

@@ -36,7 +36,6 @@ const ARM_ALLOWED_FEATURES: &[(&str, Option<Symbol>)] = &[
     ("thumb-mode", Some(sym::arm_target_feature)),
 ];
 
-// Commented features are not available in LLVM 10.0, or have since been renamed
 const AARCH64_ALLOWED_FEATURES: &[(&str, Option<Symbol>)] = &[
     // FEAT_AdvSimd
     ("neon", Some(sym::aarch64_target_feature)),
@@ -67,13 +66,13 @@ const AARCH64_ALLOWED_FEATURES: &[(&str, Option<Symbol>)] = &[
     // FEAT_DIT
     ("dit", Some(sym::aarch64_target_feature)),
     // FEAT_FLAGM
-    // ("flagm", Some(sym::aarch64_target_feature)),
+    ("flagm", Some(sym::aarch64_target_feature)),
     // FEAT_SSBS
     ("ssbs", Some(sym::aarch64_target_feature)),
     // FEAT_SB
     ("sb", Some(sym::aarch64_target_feature)),
     // FEAT_PAUTH
-    // ("pauth", Some(sym::aarch64_target_feature)),
+    ("pauth", Some(sym::aarch64_target_feature)),
     // FEAT_DPB
     ("dpb", Some(sym::aarch64_target_feature)),
     // FEAT_DPB2
@@ -93,11 +92,11 @@ const AARCH64_ALLOWED_FEATURES: &[(&str, Option<Symbol>)] = &[
     // FEAT_I8MM
     ("i8mm", Some(sym::aarch64_target_feature)),
     // FEAT_F32MM
-    // ("f32mm", Some(sym::aarch64_target_feature)),
+    ("f32mm", Some(sym::aarch64_target_feature)),
     // FEAT_F64MM
-    // ("f64mm", Some(sym::aarch64_target_feature)),
+    ("f64mm", Some(sym::aarch64_target_feature)),
     // FEAT_BF16
-    // ("bf16", Some(sym::aarch64_target_feature)),
+    ("bf16", Some(sym::aarch64_target_feature)),
     // FEAT_RAND
     ("rand", Some(sym::aarch64_target_feature)),
     // FEAT_BTI
@@ -116,13 +115,23 @@ const AARCH64_ALLOWED_FEATURES: &[(&str, Option<Symbol>)] = &[
     ("sha3", Some(sym::aarch64_target_feature)),
     // FEAT_SM3 & FEAT_SM4
     ("sm4", Some(sym::aarch64_target_feature)),
+    // FEAT_PAN
+    ("pan", Some(sym::aarch64_target_feature)),
+    // FEAT_LOR
+    ("lor", Some(sym::aarch64_target_feature)),
+    // FEAT_VHE
+    ("vh", Some(sym::aarch64_target_feature)),
+    // FEAT_PMUv3
+    ("pmuv3", Some(sym::aarch64_target_feature)),
+    // FEAT_SPE
+    ("spe", Some(sym::aarch64_target_feature)),
     ("v8.1a", Some(sym::aarch64_target_feature)),
     ("v8.2a", Some(sym::aarch64_target_feature)),
     ("v8.3a", Some(sym::aarch64_target_feature)),
     ("v8.4a", Some(sym::aarch64_target_feature)),
     ("v8.5a", Some(sym::aarch64_target_feature)),
-    // ("v8.6a", Some(sym::aarch64_target_feature)),
-    // ("v8.7a", Some(sym::aarch64_target_feature)),
+    ("v8.6a", Some(sym::aarch64_target_feature)),
+    ("v8.7a", Some(sym::aarch64_target_feature)),
 ];
 
 const X86_ALLOWED_FEATURES: &[(&str, Option<Symbol>)] = &[

compiler/rustc_metadata/src/locator.rs

@@ -236,7 +236,7 @@ use std::fmt::Write as _;
 use std::io::{Read, Result as IoResult, Write};
 use std::path::{Path, PathBuf};
 use std::{cmp, fmt, fs};
-use tracing::{debug, info, warn};
+use tracing::{debug, info};
 
 #[derive(Clone)]
 crate struct CrateLocator<'a> {
@@ -549,7 +549,7 @@ impl<'a> CrateLocator<'a> {
                         }
                     }
                     Err(err) => {
-                        warn!("no metadata found: {}", err);
+                        info!("no metadata found: {}", err);
                         continue;
                     }
                 };

compiler/rustc_resolve/src/diagnostics.rs

@@ -420,6 +420,10 @@ impl<'a> Resolver<'a> {
                 err.span_label(span, label);
 
                 if let Some((suggestions, msg, applicability)) = suggestion {
+                    if suggestions.is_empty() {
+                        err.help(&msg);
+                        return err;
+                    }
                     err.multipart_suggestion(&msg, suggestions, applicability);
                 }
 

compiler/rustc_resolve/src/lib.rs

@@ -2523,19 +2523,29 @@ impl<'a> Resolver<'a> {
                         } else {
                             (
                                 format!("use of undeclared crate or module `{}`", ident),
-                                self.find_similarly_named_module_or_crate(
-                                    ident.name,
-                                    &parent_scope.module,
-                                )
-                                .map(|sugg| {
-                                    (
-                                        vec![(ident.span, sugg.to_string())],
+                                if ident.name == sym::alloc {
+                                    Some((
+                                        vec![],
                                         String::from(
-                                            "there is a crate or module with a similar name",
+                                            "add `extern crate alloc` to use the `alloc` crate",
                                         ),
                                         Applicability::MaybeIncorrect,
+                                    ))
+                                } else {
+                                    self.find_similarly_named_module_or_crate(
+                                        ident.name,
+                                        &parent_scope.module,
                                     )
-                                }),
+                                    .map(|sugg| {
+                                        (
+                                            vec![(ident.span, sugg.to_string())],
+                                            String::from(
+                                                "there is a crate or module with a similar name",
+                                            ),
+                                            Applicability::MaybeIncorrect,
+                                        )
+                                    })
+                                },
                             )
                         }
                     } else {

library/core/src/num/mod.rs

@@ -94,7 +94,13 @@ depending on the target pointer size.
 }
 
 macro_rules! widening_impl {
-    ($SelfT:ty, $WideT:ty, $BITS:literal) => {
+    ($SelfT:ty, $WideT:ty, $BITS:literal, unsigned) => {
+        widening_impl!($SelfT, $WideT, $BITS, "");
+    };
+    ($SelfT:ty, $WideT:ty, $BITS:literal, signed) => {
+        widening_impl!($SelfT, $WideT, $BITS, "# //");
+    };
+    ($SelfT:ty, $WideT:ty, $BITS:literal, $AdaptiveTestPrefix:literal) => {
         /// Calculates the complete product `self * rhs` without the possibility to overflow.
         ///
         /// This returns the low-order (wrapping) bits and the high-order (overflow) bits
@@ -148,6 +154,33 @@ macro_rules! widening_impl {
         /// assert_eq!(5u32.carrying_mul(2, 10), (20, 0));
         /// assert_eq!(1_000_000_000u32.carrying_mul(10, 0), (1410065408, 2));
         /// assert_eq!(1_000_000_000u32.carrying_mul(10, 10), (1410065418, 2));
+        #[doc = concat!($AdaptiveTestPrefix, "assert_eq!(",
+            stringify!($SelfT), "::MAX.carrying_mul(", stringify!($SelfT), "::MAX, ", stringify!($SelfT), "::MAX), ",
+            "(0, ", stringify!($SelfT), "::MAX));"
+        )]
+        /// ```
+        ///
+        /// If `carry` is zero, this is similar to [`overflowing_mul`](Self::overflowing_mul),
+        /// except that it gives the value of the overflow instead of just whether one happened:
+        ///
+        /// ```
+        /// #![feature(bigint_helper_methods)]
+        /// let r = u8::carrying_mul(7, 13, 0);
+        /// assert_eq!((r.0, r.1 != 0), u8::overflowing_mul(7, 13));
+        /// let r = u8::carrying_mul(13, 42, 0);
+        /// assert_eq!((r.0, r.1 != 0), u8::overflowing_mul(13, 42));
+        /// ```
+        ///
+        /// The value of the first field in the returned tuple matches what you'd get
+        /// by combining the [`wrapping_mul`](Self::wrapping_mul) and
+        /// [`wrapping_add`](Self::wrapping_add) methods:
+        ///
+        /// ```
+        /// #![feature(bigint_helper_methods)]
+        /// assert_eq!(
+        ///     789_u16.carrying_mul(456, 123).0,
+        ///     789_u16.wrapping_mul(456).wrapping_add(123),
+        /// );
         /// ```
         #[unstable(feature = "bigint_helper_methods", issue = "85532")]
         #[rustc_const_unstable(feature = "bigint_helper_methods", issue = "85532")]
@@ -168,29 +201,29 @@ macro_rules! widening_impl {
 
 #[lang = "i8"]
 impl i8 {
-    widening_impl! { i8, i16, 8 }
+    widening_impl! { i8, i16, 8, signed }
     int_impl! { i8, i8, u8, 8, 7, -128, 127, 2, "-0x7e", "0xa", "0x12", "0x12", "0x48",
     "[0x12]", "[0x12]", "", "" }
 }
 
 #[lang = "i16"]
 impl i16 {
-    widening_impl! { i16, i32, 16 }
+    widening_impl! { i16, i32, 16, signed }
     int_impl! { i16, i16, u16, 16, 15, -32768, 32767, 4, "-0x5ffd", "0x3a", "0x1234", "0x3412",
     "0x2c48", "[0x34, 0x12]", "[0x12, 0x34]", "", "" }
 }
 
 #[lang = "i32"]
 impl i32 {
-    widening_impl! { i32, i64, 32 }
+    widening_impl! { i32, i64, 32, signed }
     int_impl! { i32, i32, u32, 32, 31, -2147483648, 2147483647, 8, "0x10000b3", "0xb301",
     "0x12345678", "0x78563412", "0x1e6a2c48", "[0x78, 0x56, 0x34, 0x12]",
     "[0x12, 0x34, 0x56, 0x78]", "", "" }
 }
 
 #[lang = "i64"]
 impl i64 {
-    widening_impl! { i64, i128, 64 }
+    widening_impl! { i64, i128, 64, signed }
     int_impl! { i64, i64, u64, 64, 63, -9223372036854775808, 9223372036854775807, 12,
     "0xaa00000000006e1", "0x6e10aa", "0x1234567890123456", "0x5634129078563412",
     "0x6a2c48091e6a2c48", "[0x56, 0x34, 0x12, 0x90, 0x78, 0x56, 0x34, 0x12]",
@@ -212,7 +245,7 @@ impl i128 {
 #[cfg(target_pointer_width = "16")]
 #[lang = "isize"]
 impl isize {
-    widening_impl! { isize, i32, 16 }
+    widening_impl! { isize, i32, 16, signed }
     int_impl! { isize, i16, usize, 16, 15, -32768, 32767, 4, "-0x5ffd", "0x3a", "0x1234",
     "0x3412", "0x2c48", "[0x34, 0x12]", "[0x12, 0x34]",
     usize_isize_to_xe_bytes_doc!(), usize_isize_from_xe_bytes_doc!() }
@@ -221,7 +254,7 @@ impl isize {
 #[cfg(target_pointer_width = "32")]
 #[lang = "isize"]
 impl isize {
-    widening_impl! { isize, i64, 32 }
+    widening_impl! { isize, i64, 32, signed }
     int_impl! { isize, i32, usize, 32, 31, -2147483648, 2147483647, 8, "0x10000b3", "0xb301",
     "0x12345678", "0x78563412", "0x1e6a2c48", "[0x78, 0x56, 0x34, 0x12]",
     "[0x12, 0x34, 0x56, 0x78]",
@@ -231,7 +264,7 @@ impl isize {
 #[cfg(target_pointer_width = "64")]
 #[lang = "isize"]
 impl isize {
-    widening_impl! { isize, i128, 64 }
+    widening_impl! { isize, i128, 64, signed }
     int_impl! { isize, i64, usize, 64, 63, -9223372036854775808, 9223372036854775807,
     12, "0xaa00000000006e1", "0x6e10aa",  "0x1234567890123456", "0x5634129078563412",
      "0x6a2c48091e6a2c48", "[0x56, 0x34, 0x12, 0x90, 0x78, 0x56, 0x34, 0x12]",
@@ -244,7 +277,7 @@ const ASCII_CASE_MASK: u8 = 0b0010_0000;
 
 #[lang = "u8"]
 impl u8 {
-    widening_impl! { u8, u16, 8 }
+    widening_impl! { u8, u16, 8, unsigned }
     uint_impl! { u8, u8, i8, 8, 255, 2, "0x82", "0xa", "0x12", "0x12", "0x48", "[0x12]",
     "[0x12]", "", "" }
 
@@ -793,21 +826,21 @@ impl u8 {
 
 #[lang = "u16"]
 impl u16 {
-    widening_impl! { u16, u32, 16 }
+    widening_impl! { u16, u32, 16, unsigned }
     uint_impl! { u16, u16, i16, 16, 65535, 4, "0xa003", "0x3a", "0x1234", "0x3412", "0x2c48",
     "[0x34, 0x12]", "[0x12, 0x34]", "", "" }
 }
 
 #[lang = "u32"]
 impl u32 {
-    widening_impl! { u32, u64, 32 }
+    widening_impl! { u32, u64, 32, unsigned }
     uint_impl! { u32, u32, i32, 32, 4294967295, 8, "0x10000b3", "0xb301", "0x12345678",
     "0x78563412", "0x1e6a2c48", "[0x78, 0x56, 0x34, 0x12]", "[0x12, 0x34, 0x56, 0x78]", "", "" }
 }
 
 #[lang = "u64"]
 impl u64 {
-    widening_impl! { u64, u128, 64 }
+    widening_impl! { u64, u128, 64, unsigned }
     uint_impl! { u64, u64, i64, 64, 18446744073709551615, 12, "0xaa00000000006e1", "0x6e10aa",
     "0x1234567890123456", "0x5634129078563412", "0x6a2c48091e6a2c48",
     "[0x56, 0x34, 0x12, 0x90, 0x78, 0x56, 0x34, 0x12]",
@@ -830,15 +863,15 @@ impl u128 {
 #[cfg(target_pointer_width = "16")]
 #[lang = "usize"]
 impl usize {
-    widening_impl! { usize, u32, 16 }
+    widening_impl! { usize, u32, 16, unsigned }
     uint_impl! { usize, u16, isize, 16, 65535, 4, "0xa003", "0x3a", "0x1234", "0x3412", "0x2c48",
     "[0x34, 0x12]", "[0x12, 0x34]",
     usize_isize_to_xe_bytes_doc!(), usize_isize_from_xe_bytes_doc!() }
 }
 #[cfg(target_pointer_width = "32")]
 #[lang = "usize"]
 impl usize {
-    widening_impl! { usize, u64, 32 }
+    widening_impl! { usize, u64, 32, unsigned }
     uint_impl! { usize, u32, isize, 32, 4294967295, 8, "0x10000b3", "0xb301", "0x12345678",
     "0x78563412", "0x1e6a2c48", "[0x78, 0x56, 0x34, 0x12]", "[0x12, 0x34, 0x56, 0x78]",
     usize_isize_to_xe_bytes_doc!(), usize_isize_from_xe_bytes_doc!() }
@@ -847,7 +880,7 @@ impl usize {
 #[cfg(target_pointer_width = "64")]
 #[lang = "usize"]
 impl usize {
-    widening_impl! { usize, u128, 64 }
+    widening_impl! { usize, u128, 64, unsigned }
     uint_impl! { usize, u64, isize, 64, 18446744073709551615, 12, "0xaa00000000006e1", "0x6e10aa",
     "0x1234567890123456", "0x5634129078563412", "0x6a2c48091e6a2c48",
     "[0x56, 0x34, 0x12, 0x90, 0x78, 0x56, 0x34, 0x12]",

library/core/src/num/uint_macros.rs

@@ -1504,6 +1504,8 @@ macro_rules! uint_impl {
         /// additional bit of overflow. This allows for chaining together multiple additions
         /// to create "big integers" which represent larger values.
         ///
+        #[doc = concat!("This can be thought of as a ", stringify!($BITS), "-bit \"full adder\", in the electronics sense.")]
+        ///
         /// # Examples
         ///
         /// Basic usage
@@ -1513,7 +1515,20 @@ macro_rules! uint_impl {
         #[doc = concat!("assert_eq!(5", stringify!($SelfT), ".carrying_add(2, false), (7, false));")]
         #[doc = concat!("assert_eq!(5", stringify!($SelfT), ".carrying_add(2, true), (8, false));")]
         #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MAX.carrying_add(1, false), (0, true));")]
+        #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MAX.carrying_add(0, true), (0, true));")]
         #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MAX.carrying_add(1, true), (1, true));")]
+        #[doc = concat!("assert_eq!(",
+            stringify!($SelfT), "::MAX.carrying_add(", stringify!($SelfT), "::MAX, true), ",
+            "(", stringify!($SelfT), "::MAX, true));"
+        )]
+        /// ```
+        ///
+        /// If `carry` is false, this method is equivalent to [`overflowing_add`](Self::overflowing_add):
+        ///
+        /// ```
+        /// #![feature(bigint_helper_methods)]
+        #[doc = concat!("assert_eq!(5_", stringify!($SelfT), ".carrying_add(2, false), 5_", stringify!($SelfT), ".overflowing_add(2));")]
+        #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MAX.carrying_add(1, false), ", stringify!($SelfT), "::MAX.overflowing_add(1));")]
         /// ```
         #[unstable(feature = "bigint_helper_methods", issue = "85532")]
         #[rustc_const_unstable(feature = "const_bigint_helper_methods", issue = "85532")]

src/doc/unstable-book/src/library-features/asm.md

@@ -885,5 +885,7 @@ The compiler performs some additional checks on options:
     - You are responsible for switching any target-specific state (e.g. thread-local storage, stack bounds).
     - The set of memory locations that you may access is the intersection of those allowed by the `asm!` blocks you entered and exited.
 - You cannot assume that an `asm!` block will appear exactly once in the output binary. The compiler is allowed to instantiate multiple copies of the `asm!` block, for example when the function containing it is inlined in multiple places.
+- On x86, inline assembly must not end with an instruction prefix (such as `LOCK`) that would apply to instructions generated by the compiler.
+  - The compiler is currently unable to detect this due to the way inline assembly is compiled, but may catch and reject this in the future.
 
 > **Note**: As a general rule, the flags covered by `preserves_flags` are those which are *not* preserved when performing a function call.

src/librustdoc/html/static/css/rustdoc.css

@@ -156,7 +156,8 @@ h1.fqn > .in-band > a:hover {
 	section hierarchies. */
 h2,
 .top-doc h3,
-.top-doc h4 {
+.top-doc h4,
+.sidebar .others h3 {
 	border-bottom: 1px solid;
 }
 h3.code-header {

src/librustdoc/html/static/js/main.js

@@ -566,6 +566,7 @@ function hideThemeButtonState() {
     // delayed sidebar rendering.
     window.initSidebarItems = function(items) {
         var sidebar = document.getElementsByClassName("sidebar-elems")[0];
+        var others;
         var current = window.sidebarCurrent;
 
         function addSidebarCrates(crates) {
@@ -594,7 +595,7 @@ function hideThemeButtonState() {
                 li.appendChild(link);
                 ul.appendChild(li);
             }
-            sidebar.appendChild(div);
+            others.appendChild(div);
         }
 
         function block(shortty, longty) {
@@ -635,10 +636,14 @@ function hideThemeButtonState() {
                 ul.appendChild(li);
             }
             div.appendChild(ul);
-            sidebar.appendChild(div);
+            others.appendChild(div);
         }
 
         if (sidebar) {
+            others = document.createElement("div");
+            others.className = "others";
+            sidebar.appendChild(others);
+
             var isModule = hasClass(document.body, "mod");
             if (!isModule) {
                 block("primitive", "Primitive Types");