Rollup of 9 pull requests

Cargo.lock

@@ -987,9 +987,9 @@ dependencies = [
 
 [[package]]
 name = "dlmalloc"
-version = "0.1.4"
+version = "0.2.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "35055b1021724f4eb5262eb49130eebff23fc59fc5a14160e05faad8eeb36673"
+checksum = "332570860c2edf2d57914987bf9e24835425f75825086b6ba7d1e6a3e4f1f254"
 dependencies = [
  "compiler_builtins",
  "libc",

compiler/rustc_errors/src/diagnostic_builder.rs

@@ -184,16 +184,18 @@ impl<'a> DiagnosticBuilder<'a> {
         self.cancel();
     }
 
-    /// Adds a span/label to be included in the resulting snippet.
+    /// Appends a labeled span to the diagnostic.
     ///
-    /// This is pushed onto the [`MultiSpan`] that was created when the diagnostic
-    /// was first built. That means it will be shown together with the original
-    /// span/label, *not* a span added by one of the `span_{note,warn,help,suggestions}` methods.
+    /// Labels are used to convey additional context for the diagnostic's primary span. They will
+    /// be shown together with the original diagnostic's span, *not* with spans added by
+    /// `span_note`, `span_help`, etc. Therefore, if the primary span is not displayable (because
+    /// the span is `DUMMY_SP` or the source code isn't found), labels will not be displayed
+    /// either.
     ///
-    /// This span is *not* considered a ["primary span"][`MultiSpan`]; only
-    /// the `Span` supplied when creating the diagnostic is primary.
-    ///
-    /// [`MultiSpan`]: ../rustc_span/struct.MultiSpan.html
+    /// Implementation-wise, the label span is pushed onto the [`MultiSpan`] that was created when
+    /// the diagnostic was constructed. However, the label span is *not* considered a
+    /// ["primary span"][`MultiSpan`]; only the `Span` supplied when creating the diagnostic is
+    /// primary.
     pub fn span_label(&mut self, span: Span, label: impl Into<String>) -> &mut Self {
         self.0.diagnostic.span_label(span, label);
         self

compiler/rustc_middle/src/mir/mod.rs

@@ -420,7 +420,9 @@ impl<'tcx> Body<'tcx> {
     /// Returns an iterator over all user-defined variables and compiler-generated temporaries (all
     /// locals that are neither arguments nor the return place).
     #[inline]
-    pub fn vars_and_temps_iter(&self) -> impl Iterator<Item = Local> + ExactSizeIterator {
+    pub fn vars_and_temps_iter(
+        &self,
+    ) -> impl DoubleEndedIterator<Item = Local> + ExactSizeIterator {
         let arg_count = self.arg_count;
         let local_count = self.local_decls.len();
         (arg_count + 1..local_count).map(Local::new)

compiler/rustc_mir/src/transform/inline.rs

@@ -459,6 +459,7 @@ impl Inliner<'tcx> {
                     tcx: self.tcx,
                     callsite_span: callsite.source_info.span,
                     body_span: callee_body.span,
+                    always_live_locals: BitSet::new_filled(callee_body.local_decls.len()),
                 };
 
                 // Map all `Local`s, `SourceScope`s and `BasicBlock`s to new ones
@@ -490,6 +491,34 @@ impl Inliner<'tcx> {
                     }
                 }
 
+                // If there are any locals without storage markers, give them storage only for the
+                // duration of the call.
+                for local in callee_body.vars_and_temps_iter() {
+                    if integrator.always_live_locals.contains(local) {
+                        let new_local = integrator.map_local(local);
+                        caller_body[callsite.block].statements.push(Statement {
+                            source_info: callsite.source_info,
+                            kind: StatementKind::StorageLive(new_local),
+                        });
+                    }
+                }
+                if let Some(block) = callsite.target {
+                    // To avoid repeated O(n) insert, push any new statements to the end and rotate
+                    // the slice once.
+                    let mut n = 0;
+                    for local in callee_body.vars_and_temps_iter().rev() {
+                        if integrator.always_live_locals.contains(local) {
+                            let new_local = integrator.map_local(local);
+                            caller_body[block].statements.push(Statement {
+                                source_info: callsite.source_info,
+                                kind: StatementKind::StorageDead(new_local),
+                            });
+                            n += 1;
+                        }
+                    }
+                    caller_body[block].statements.rotate_right(n);
+                }
+
                 // Insert all of the (mapped) parts of the callee body into the caller.
                 caller_body.local_decls.extend(
                     // FIXME(eddyb) make `Range<Local>` iterable so that we can use
@@ -670,6 +699,7 @@ struct Integrator<'a, 'tcx> {
     tcx: TyCtxt<'tcx>,
     callsite_span: Span,
     body_span: Span,
+    always_live_locals: BitSet<Local>,
 }
 
 impl<'a, 'tcx> Integrator<'a, 'tcx> {
@@ -759,6 +789,15 @@ impl<'a, 'tcx> MutVisitor<'tcx> for Integrator<'a, 'tcx> {
         }
     }
 
+    fn visit_statement(&mut self, statement: &mut Statement<'tcx>, location: Location) {
+        if let StatementKind::StorageLive(local) | StatementKind::StorageDead(local) =
+            statement.kind
+        {
+            self.always_live_locals.remove(local);
+        }
+        self.super_statement(statement, location);
+    }
+
     fn visit_terminator(&mut self, terminator: &mut Terminator<'tcx>, loc: Location) {
         // Don't try to modify the implicit `_0` access on return (`return` terminators are
         // replaced down below anyways).

library/alloc/src/alloc.rs

@@ -23,6 +23,8 @@ extern "Rust" {
     // (the code expanding that attribute macro generates those functions), or to call
     // the default implementations in libstd (`__rdl_alloc` etc. in `library/std/src/alloc.rs`)
     // otherwise.
+    // The rustc fork of LLVM also special-cases these function names to be able to optimize them
+    // like `malloc`, `realloc`, and `free`, respectively.
     #[rustc_allocator]
     #[rustc_allocator_nounwind]
     fn __rust_alloc(size: usize, align: usize) -> *mut u8;

library/std/Cargo.toml

@@ -36,7 +36,7 @@ features = ['read_core', 'elf', 'macho', 'pe']
 rand = "0.7"
 
 [target.'cfg(any(all(target_arch = "wasm32", not(target_os = "emscripten")), all(target_vendor = "fortanix", target_env = "sgx")))'.dependencies]
-dlmalloc = { version = "0.1", features = ['rustc-dep-of-std'] }
+dlmalloc = { version = "0.2.1", features = ['rustc-dep-of-std'] }
 
 [target.x86_64-fortanix-unknown-sgx.dependencies]
 fortanix-sgx-abi = { version = "0.3.2", features = ['rustc-dep-of-std'] }

library/std/src/fs/tests.rs

@@ -1341,6 +1341,9 @@ fn metadata_access_times() {
 #[test]
 fn symlink_hard_link() {
     let tmpdir = tmpdir();
+    if !got_symlink_permission(&tmpdir) {
+        return;
+    };
 
     // Create "file", a file.
     check!(fs::File::create(tmpdir.join("file")));

library/std/src/sys/sgx/abi/mem.rs

@@ -12,6 +12,18 @@ pub(crate) unsafe fn rel_ptr_mut<T>(offset: u64) -> *mut T {
 
 extern "C" {
     static ENCLAVE_SIZE: usize;
+    static HEAP_BASE: u64;
+    static HEAP_SIZE: usize;
+}
+
+/// Returns the base memory address of the heap
+pub(crate) fn heap_base() -> *const u8 {
+    unsafe { rel_ptr_mut(HEAP_BASE) }
+}
+
+/// Returns the size of the heap
+pub(crate) fn heap_size() -> usize {
+    unsafe { HEAP_SIZE }
 }
 
 // Do not remove inline: will result in relocation failure

library/std/src/sys/sgx/alloc.rs

@@ -1,4 +1,7 @@
 use crate::alloc::{GlobalAlloc, Layout, System};
+use crate::ptr;
+use crate::sys::sgx::abi::mem as sgx_mem;
+use core::sync::atomic::{AtomicBool, Ordering};
 
 use super::waitqueue::SpinMutex;
 
@@ -10,7 +13,48 @@ use super::waitqueue::SpinMutex;
 // dlmalloc.c from C to Rust.
 #[cfg_attr(test, linkage = "available_externally")]
 #[export_name = "_ZN16__rust_internals3std3sys3sgx5alloc8DLMALLOCE"]
-static DLMALLOC: SpinMutex<dlmalloc::Dlmalloc> = SpinMutex::new(dlmalloc::DLMALLOC_INIT);
+static DLMALLOC: SpinMutex<dlmalloc::Dlmalloc<Sgx>> =
+    SpinMutex::new(dlmalloc::Dlmalloc::new_with_allocator(Sgx {}));
+
+struct Sgx;
+
+unsafe impl dlmalloc::Allocator for Sgx {
+    /// Allocs system resources
+    fn alloc(&self, _size: usize) -> (*mut u8, usize, u32) {
+        static INIT: AtomicBool = AtomicBool::new(false);
+
+        // No ordering requirement since this function is protected by the global lock.
+        if !INIT.swap(true, Ordering::Relaxed) {
+            (sgx_mem::heap_base() as _, sgx_mem::heap_size(), 0)
+        } else {
+            (ptr::null_mut(), 0, 0)
+        }
+    }
+
+    fn remap(&self, _ptr: *mut u8, _oldsize: usize, _newsize: usize, _can_move: bool) -> *mut u8 {
+        ptr::null_mut()
+    }
+
+    fn free_part(&self, _ptr: *mut u8, _oldsize: usize, _newsize: usize) -> bool {
+        false
+    }
+
+    fn free(&self, _ptr: *mut u8, _size: usize) -> bool {
+        return false;
+    }
+
+    fn can_release_part(&self, _flags: u32) -> bool {
+        false
+    }
+
+    fn allocates_zeros(&self) -> bool {
+        false
+    }
+
+    fn page_size(&self) -> usize {
+        0x1000
+    }
+}
 
 #[stable(feature = "alloc_system_type", since = "1.28.0")]
 unsafe impl GlobalAlloc for System {

library/std/src/sys/wasm/alloc.rs

@@ -18,7 +18,7 @@
 
 use crate::alloc::{GlobalAlloc, Layout, System};
 
-static mut DLMALLOC: dlmalloc::Dlmalloc = dlmalloc::DLMALLOC_INIT;
+static mut DLMALLOC: dlmalloc::Dlmalloc = dlmalloc::Dlmalloc::new();
 
 #[stable(feature = "alloc_system_type", since = "1.28.0")]
 unsafe impl GlobalAlloc for System {

src/librustdoc/html/highlight.rs

@@ -46,7 +46,9 @@ fn write_header(out: &mut String, class: Option<&str>) {
 }
 
 fn write_code(out: &mut String, src: &str) {
-    Classifier::new(src).highlight(&mut |highlight| {
+    // This replace allows to fix how the code source with DOS backline characters is displayed.
+    let src = src.replace("\r\n", "\n");
+    Classifier::new(&src).highlight(&mut |highlight| {
         match highlight {
             Highlight::Token { text, class } => string(out, Escape(text), class),
             Highlight::EnterSpan { class } => enter_span(out, class),

src/librustdoc/html/highlight/fixtures/dos_line.html

@@ -0,0 +1,3 @@
+<span class="kw">pub</span> <span class="kw">fn</span> <span class="ident">foo</span>() {
+<span class="macro">println</span><span class="macro">!</span>(<span class="string">&quot;foo&quot;</span>);
+}

src/librustdoc/html/highlight/tests.rs

@@ -1,17 +1,6 @@
 use super::write_code;
 use expect_test::expect_file;
 
-#[test]
-fn test_html_highlighting() {
-    let src = include_str!("fixtures/sample.rs");
-    let html = {
-        let mut out = String::new();
-        write_code(&mut out, src);
-        format!("{}<pre><code>{}</code></pre>\n", STYLE, out)
-    };
-    expect_file!["fixtures/sample.html"].assert_eq(&html);
-}
-
 const STYLE: &str = r#"
 <style>
 .kw { color: #8959A8; }
@@ -23,3 +12,24 @@ const STYLE: &str = r#"
 .question-mark { color: #ff9011; }
 </style>
 "#;
+
+#[test]
+fn test_html_highlighting() {
+    let src = include_str!("fixtures/sample.rs");
+    let html = {
+        let mut out = String::new();
+        write_code(&mut out, src);
+        format!("{}<pre><code>{}</code></pre>\n", STYLE, out)
+    };
+    expect_file!["fixtures/sample.html"].assert_eq(&html);
+}
+
+#[test]
+fn test_dos_backline() {
+    let src = "pub fn foo() {\r\n\
+    println!(\"foo\");\r\n\
+}\r\n";
+    let mut html = String::new();
+    write_code(&mut html, src);
+    expect_file!["fixtures/dos_line.html"].assert_eq(&html);
+}

src/librustdoc/passes/html_tags.rs

@@ -4,7 +4,7 @@ use crate::core::DocContext;
 use crate::fold::DocFolder;
 use crate::html::markdown::opts;
 use core::ops::Range;
-use pulldown_cmark::{Event, Parser};
+use pulldown_cmark::{Event, Parser, Tag};
 use rustc_session::lint;
 use std::iter::Peekable;
 use std::str::CharIndices;
@@ -196,14 +196,17 @@ impl<'a, 'tcx> DocFolder for InvalidHtmlTagsLinter<'a, 'tcx> {
 
             let mut tags = Vec::new();
             let mut is_in_comment = None;
+            let mut in_code_block = false;
 
             let p = Parser::new_ext(&dox, opts()).into_offset_iter();
 
             for (event, range) in p {
                 match event {
-                    Event::Html(text) | Event::Text(text) => {
+                    Event::Start(Tag::CodeBlock(_)) => in_code_block = true,
+                    Event::Html(text) | Event::Text(text) if !in_code_block => {
                         extract_tags(&mut tags, &text, range, &mut is_in_comment, &report_diag)
                     }
+                    Event::End(Tag::CodeBlock(_)) => in_code_block = false,
                     _ => {}
                 }
             }

src/test/codegen/internalize-closures.rs

@@ -1,4 +1,4 @@
-// compile-flags: -C no-prepopulate-passes
+// compile-flags: -C no-prepopulate-passes -Zmir-opt-level=0
 
 pub fn main() {
 

src/test/codegen/issue-37945.rs

@@ -1,26 +1,34 @@
-// compile-flags: -O
+// compile-flags: -O -Zmerge-functions=disabled
 // ignore-x86
 // ignore-arm
 // ignore-emscripten
 // ignore-gnux32
 // ignore 32-bit platforms (LLVM has a bug with them)
 
-// See issue #37945.
+// Check that LLVM understands that `Iter` pointer is not null. Issue #37945.
 
 #![crate_type = "lib"]
 
 use std::slice::Iter;
 
-// CHECK-LABEL: @is_empty_1
 #[no_mangle]
 pub fn is_empty_1(xs: Iter<f32>) -> bool {
-// CHECK-NOT: icmp eq float* {{.*}}, null
+// CHECK-LABEL: @is_empty_1(
+// CHECK-NEXT:  start:
+// CHECK-NEXT:    [[A:%.*]] = icmp ne i32* %xs.1, null
+// CHECK-NEXT:    tail call void @llvm.assume(i1 [[A]])
+// CHECK-NEXT:    [[B:%.*]] = icmp eq i32* %xs.0, %xs.1
+// CHECK-NEXT:    ret i1 [[B:%.*]]
     {xs}.next().is_none()
 }
 
-// CHECK-LABEL: @is_empty_2
 #[no_mangle]
 pub fn is_empty_2(xs: Iter<f32>) -> bool {
-// CHECK-NOT: icmp eq float* {{.*}}, null
+// CHECK-LABEL: @is_empty_2
+// CHECK-NEXT:  start:
+// CHECK-NEXT:    [[C:%.*]] = icmp ne i32* %xs.1, null
+// CHECK-NEXT:    tail call void @llvm.assume(i1 [[C]])
+// CHECK-NEXT:    [[D:%.*]] = icmp eq i32* %xs.0, %xs.1
+// CHECK-NEXT:    ret i1 [[D:%.*]]
     xs.map(|&x| x).next().is_none()
 }

src/test/codegen/vec-shrink-panic.rs

@@ -15,9 +15,9 @@ pub fn shrink_to_fit(vec: &mut Vec<u32>) {
 
 // CHECK-LABEL: @issue71861
 #[no_mangle]
-pub fn issue71861(n: usize) -> Box<[u32]> {
+pub fn issue71861(vec: Vec<u32>) -> Box<[u32]> {
     // CHECK-NOT: panic
-    vec![0; n].into_boxed_slice()
+    vec.into_boxed_slice()
 }
 
 // CHECK-LABEL: @issue75636

src/test/mir-opt/inline/inline_diverging.h.Inline.diff

@@ -40,6 +40,7 @@
 -                                          // mir::Constant
                                            // + span: $DIR/inline-diverging.rs:22:16: 22:21
                                            // + literal: Const { ty: fn() -> ! {sleep}, val: Value(Scalar(<ZST>)) }
++         StorageLive(_6);                 // scope 0 at $DIR/inline-diverging.rs:22:5: 22:22
 +         StorageLive(_3);                 // scope 1 at $DIR/inline-diverging.rs:22:5: 22:22
 +         StorageLive(_4);                 // scope 1 at $DIR/inline-diverging.rs:22:5: 22:22
 +         _4 = &_2;                        // scope 1 at $DIR/inline-diverging.rs:22:5: 22:22