Rollup of 10 pull requests

compiler/rustc_attr_data_structures/src/attributes.rs

@@ -110,6 +110,22 @@ pub enum DeprecatedSince {
     Err,
 }
 
+#[derive(
+    Copy,
+    Debug,
+    Eq,
+    PartialEq,
+    Encodable,
+    Decodable,
+    Clone,
+    HashStable_Generic,
+    PrintAttribute
+)]
+pub enum CoverageStatus {
+    On,
+    Off,
+}
+
 impl Deprecation {
     /// Whether an item marked with #[deprecated(since = "X")] is currently
     /// deprecated (i.e., whether X is not greater than the current rustc
@@ -274,6 +290,9 @@ pub enum AttributeKind {
     /// Represents `#[const_trait]`.
     ConstTrait(Span),
 
+    /// Represents `#[coverage]`.
+    Coverage(Span, CoverageStatus),
+
     ///Represents `#[rustc_deny_explicit_impl]`.
     DenyExplicitImpl(Span),
 

compiler/rustc_attr_data_structures/src/encode_cross_crate.rs

@@ -28,6 +28,7 @@ impl AttributeKind {
             ConstStability { .. } => Yes,
             ConstStabilityIndirect => No,
             ConstTrait(..) => No,
+            Coverage(..) => No,
             DenyExplicitImpl(..) => No,
             Deprecation { .. } => Yes,
             DoNotImplementViaObject(..) => No,

compiler/rustc_attr_parsing/src/attributes/codegen_attrs.rs

@@ -1,4 +1,4 @@
-use rustc_attr_data_structures::{AttributeKind, OptimizeAttr, UsedBy};
+use rustc_attr_data_structures::{AttributeKind, CoverageStatus, OptimizeAttr, UsedBy};
 use rustc_feature::{AttributeTemplate, template};
 use rustc_session::parse::feature_err;
 use rustc_span::{Span, Symbol, sym};
@@ -52,6 +52,45 @@ impl<S: Stage> NoArgsAttributeParser<S> for ColdParser {
     const CREATE: fn(Span) -> AttributeKind = AttributeKind::Cold;
 }
 
+pub(crate) struct CoverageParser;
+
+impl<S: Stage> SingleAttributeParser<S> for CoverageParser {
+    const PATH: &[Symbol] = &[sym::coverage];
+    const ATTRIBUTE_ORDER: AttributeOrder = AttributeOrder::KeepOutermost;
+    const ON_DUPLICATE: OnDuplicate<S> = OnDuplicate::Error;
+    const TEMPLATE: AttributeTemplate = template!(OneOf: &[sym::off, sym::on]);
+
+    fn convert(cx: &mut AcceptContext<'_, '_, S>, args: &ArgParser<'_>) -> Option<AttributeKind> {
+        let Some(args) = args.list() else {
+            cx.expected_specific_argument_and_list(cx.attr_span, vec!["on", "off"]);
+            return None;
+        };
+
+        let Some(arg) = args.single() else {
+            cx.expected_single_argument(args.span);
+            return None;
+        };
+
+        let fail_incorrect_argument = |span| cx.expected_specific_argument(span, vec!["on", "off"]);
+
+        let Some(arg) = arg.meta_item() else {
+            fail_incorrect_argument(args.span);
+            return None;
+        };
+
+        let status = match arg.path().word_sym() {
+            Some(sym::off) => CoverageStatus::Off,
+            Some(sym::on) => CoverageStatus::On,
+            None | Some(_) => {
+                fail_incorrect_argument(arg.span());
+                return None;
+            }
+        };
+
+        Some(AttributeKind::Coverage(cx.attr_span, status))
+    }
+}
+
 pub(crate) struct ExportNameParser;
 
 impl<S: Stage> SingleAttributeParser<S> for ExportNameParser {

compiler/rustc_attr_parsing/src/context.rs

@@ -15,8 +15,9 @@ use rustc_span::{DUMMY_SP, ErrorGuaranteed, Span, Symbol, sym};
 
 use crate::attributes::allow_unstable::{AllowConstFnUnstableParser, AllowInternalUnstableParser};
 use crate::attributes::codegen_attrs::{
-    ColdParser, ExportNameParser, NakedParser, NoMangleParser, OmitGdbPrettyPrinterSectionParser,
-    OptimizeParser, TargetFeatureParser, TrackCallerParser, UsedParser,
+    ColdParser, CoverageParser, ExportNameParser, NakedParser, NoMangleParser,
+    OmitGdbPrettyPrinterSectionParser, OptimizeParser, TargetFeatureParser, TrackCallerParser,
+    UsedParser,
 };
 use crate::attributes::confusables::ConfusablesParser;
 use crate::attributes::deprecation::DeprecationParser;
@@ -136,6 +137,7 @@ attribute_parsers!(
         // tidy-alphabetical-end
 
         // tidy-alphabetical-start
+        Single<CoverageParser>,
         Single<DeprecationParser>,
         Single<DummyParser>,
         Single<ExportNameParser>,
@@ -449,6 +451,25 @@ impl<'f, 'sess: 'f, S: Stage> AcceptContext<'f, 'sess, S> {
             reason: AttributeParseErrorReason::ExpectedSpecificArgument {
                 possibilities,
                 strings: false,
+                list: false,
+            },
+        })
+    }
+
+    pub(crate) fn expected_specific_argument_and_list(
+        &self,
+        span: Span,
+        possibilities: Vec<&'static str>,
+    ) -> ErrorGuaranteed {
+        self.emit_err(AttributeParseError {
+            span,
+            attr_span: self.attr_span,
+            template: self.template.clone(),
+            attribute: self.attr_path.clone(),
+            reason: AttributeParseErrorReason::ExpectedSpecificArgument {
+                possibilities,
+                strings: false,
+                list: true,
             },
         })
     }
@@ -466,6 +487,7 @@ impl<'f, 'sess: 'f, S: Stage> AcceptContext<'f, 'sess, S> {
             reason: AttributeParseErrorReason::ExpectedSpecificArgument {
                 possibilities,
                 strings: true,
+                list: false,
             },
         })
     }

compiler/rustc_attr_parsing/src/session_diagnostics.rs

@@ -525,15 +525,22 @@ pub(crate) struct LinkOrdinalOutOfRange {
 
 pub(crate) enum AttributeParseErrorReason {
     ExpectedNoArgs,
-    ExpectedStringLiteral { byte_string: Option<Span> },
+    ExpectedStringLiteral {
+        byte_string: Option<Span>,
+    },
     ExpectedIntegerLiteral,
     ExpectedAtLeastOneArgument,
     ExpectedSingleArgument,
     ExpectedList,
     UnexpectedLiteral,
     ExpectedNameValue(Option<Symbol>),
     DuplicateKey(Symbol),
-    ExpectedSpecificArgument { possibilities: Vec<&'static str>, strings: bool },
+    ExpectedSpecificArgument {
+        possibilities: Vec<&'static str>,
+        strings: bool,
+        /// Should we tell the user to write a list when they didn't?
+        list: bool,
+    },
 }
 
 pub(crate) struct AttributeParseError {
@@ -607,7 +614,11 @@ impl<'a, G: EmissionGuarantee> Diagnostic<'a, G> for AttributeParseError {
                     format!("expected this to be of the form `{name} = \"...\"`"),
                 );
             }
-            AttributeParseErrorReason::ExpectedSpecificArgument { possibilities, strings } => {
+            AttributeParseErrorReason::ExpectedSpecificArgument {
+                possibilities,
+                strings,
+                list: false,
+            } => {
                 let quote = if strings { '"' } else { '`' };
                 match possibilities.as_slice() {
                     &[] => {}
@@ -633,6 +644,38 @@ impl<'a, G: EmissionGuarantee> Diagnostic<'a, G> for AttributeParseError {
                     }
                 }
             }
+            AttributeParseErrorReason::ExpectedSpecificArgument {
+                possibilities,
+                strings,
+                list: true,
+            } => {
+                let quote = if strings { '"' } else { '`' };
+                match possibilities.as_slice() {
+                    &[] => {}
+                    &[x] => {
+                        diag.span_label(
+                            self.span,
+                            format!(
+                                "this attribute is only valid with {quote}{x}{quote} as an argument"
+                            ),
+                        );
+                    }
+                    [first, second] => {
+                        diag.span_label(self.span, format!("this attribute is only valid with either {quote}{first}{quote} or {quote}{second}{quote} as an argument"));
+                    }
+                    [first @ .., second_to_last, last] => {
+                        let mut res = String::new();
+                        for i in first {
+                            res.push_str(&format!("{quote}{i}{quote}, "));
+                        }
+                        res.push_str(&format!(
+                            "{quote}{second_to_last}{quote} or {quote}{last}{quote}"
+                        ));
+
+                        diag.span_label(self.span, format!("this attribute is only valid with one of the following arguments: {res}"));
+                    }
+                }
+            }
         }
 
         let suggestions = self.template.suggestions(false, &name);

compiler/rustc_codegen_llvm/src/back/write.rs

@@ -879,9 +879,7 @@ pub(crate) fn codegen(
                     .generic_activity_with_arg("LLVM_module_codegen_embed_bitcode", &*module.name);
                 let thin_bc =
                     module.thin_lto_buffer.as_deref().expect("cannot find embedded bitcode");
-                unsafe {
-                    embed_bitcode(cgcx, llcx, llmod, &config.bc_cmdline, &thin_bc);
-                }
+                embed_bitcode(cgcx, llcx, llmod, &config.bc_cmdline, &thin_bc);
             }
         }
 
@@ -945,7 +943,7 @@ pub(crate) fn codegen(
             // binaries. So we must clone the module to produce the asm output
             // if we are also producing object code.
             let llmod = if let EmitObj::ObjectCode(_) = config.emit_obj {
-                unsafe { llvm::LLVMCloneModule(llmod) }
+                llvm::LLVMCloneModule(llmod)
             } else {
                 llmod
             };
@@ -1073,7 +1071,7 @@ pub(crate) fn bitcode_section_name(cgcx: &CodegenContext<LlvmCodegenBackend>) ->
 }
 
 /// Embed the bitcode of an LLVM module for LTO in the LLVM module itself.
-unsafe fn embed_bitcode(
+fn embed_bitcode(
     cgcx: &CodegenContext<LlvmCodegenBackend>,
     llcx: &llvm::Context,
     llmod: &llvm::Module,
@@ -1115,43 +1113,40 @@ unsafe fn embed_bitcode(
     // Unfortunately, LLVM provides no way to set custom section flags. For ELF
     // and COFF we emit the sections using module level inline assembly for that
     // reason (see issue #90326 for historical background).
-    unsafe {
-        if cgcx.target_is_like_darwin
-            || cgcx.target_is_like_aix
-            || cgcx.target_arch == "wasm32"
-            || cgcx.target_arch == "wasm64"
-        {
-            // We don't need custom section flags, create LLVM globals.
-            let llconst = common::bytes_in_context(llcx, bitcode);
-            let llglobal =
-                llvm::add_global(llmod, common::val_ty(llconst), c"rustc.embedded.module");
-            llvm::set_initializer(llglobal, llconst);
-
-            llvm::set_section(llglobal, bitcode_section_name(cgcx));
-            llvm::set_linkage(llglobal, llvm::Linkage::PrivateLinkage);
-            llvm::LLVMSetGlobalConstant(llglobal, llvm::True);
-
-            let llconst = common::bytes_in_context(llcx, cmdline.as_bytes());
-            let llglobal =
-                llvm::add_global(llmod, common::val_ty(llconst), c"rustc.embedded.cmdline");
-            llvm::set_initializer(llglobal, llconst);
-            let section = if cgcx.target_is_like_darwin {
-                c"__LLVM,__cmdline"
-            } else if cgcx.target_is_like_aix {
-                c".info"
-            } else {
-                c".llvmcmd"
-            };
-            llvm::set_section(llglobal, section);
-            llvm::set_linkage(llglobal, llvm::Linkage::PrivateLinkage);
+
+    if cgcx.target_is_like_darwin
+        || cgcx.target_is_like_aix
+        || cgcx.target_arch == "wasm32"
+        || cgcx.target_arch == "wasm64"
+    {
+        // We don't need custom section flags, create LLVM globals.
+        let llconst = common::bytes_in_context(llcx, bitcode);
+        let llglobal = llvm::add_global(llmod, common::val_ty(llconst), c"rustc.embedded.module");
+        llvm::set_initializer(llglobal, llconst);
+
+        llvm::set_section(llglobal, bitcode_section_name(cgcx));
+        llvm::set_linkage(llglobal, llvm::Linkage::PrivateLinkage);
+        llvm::LLVMSetGlobalConstant(llglobal, llvm::True);
+
+        let llconst = common::bytes_in_context(llcx, cmdline.as_bytes());
+        let llglobal = llvm::add_global(llmod, common::val_ty(llconst), c"rustc.embedded.cmdline");
+        llvm::set_initializer(llglobal, llconst);
+        let section = if cgcx.target_is_like_darwin {
+            c"__LLVM,__cmdline"
+        } else if cgcx.target_is_like_aix {
+            c".info"
         } else {
-            // We need custom section flags, so emit module-level inline assembly.
-            let section_flags = if cgcx.is_pe_coff { "n" } else { "e" };
-            let asm = create_section_with_flags_asm(".llvmbc", section_flags, bitcode);
-            llvm::append_module_inline_asm(llmod, &asm);
-            let asm = create_section_with_flags_asm(".llvmcmd", section_flags, cmdline.as_bytes());
-            llvm::append_module_inline_asm(llmod, &asm);
-        }
+            c".llvmcmd"
+        };
+        llvm::set_section(llglobal, section);
+        llvm::set_linkage(llglobal, llvm::Linkage::PrivateLinkage);
+    } else {
+        // We need custom section flags, so emit module-level inline assembly.
+        let section_flags = if cgcx.is_pe_coff { "n" } else { "e" };
+        let asm = create_section_with_flags_asm(".llvmbc", section_flags, bitcode);
+        llvm::append_module_inline_asm(llmod, &asm);
+        let asm = create_section_with_flags_asm(".llvmcmd", section_flags, cmdline.as_bytes());
+        llvm::append_module_inline_asm(llmod, &asm);
     }
 }
 

compiler/rustc_codegen_llvm/src/builder.rs

@@ -302,10 +302,7 @@ impl<'a, 'll, 'tcx> BuilderMethods<'a, 'tcx> for Builder<'a, 'll, 'tcx> {
             return;
         }
 
-        let id_str = "branch_weights";
-        let id = unsafe {
-            llvm::LLVMMDStringInContext2(self.cx.llcx, id_str.as_ptr().cast(), id_str.len())
-        };
+        let id = self.cx.create_metadata(b"branch_weights");
 
         // For switch instructions with 2 targets, the `llvm.expect` intrinsic is used.
         // This function handles switch instructions with more than 2 targets and it needs to
@@ -637,17 +634,16 @@ impl<'a, 'll, 'tcx> BuilderMethods<'a, 'tcx> for Builder<'a, 'll, 'tcx> {
         } else if place.layout.is_llvm_immediate() {
             let mut const_llval = None;
             let llty = place.layout.llvm_type(self);
-            unsafe {
-                if let Some(global) = llvm::LLVMIsAGlobalVariable(place.val.llval) {
-                    if llvm::LLVMIsGlobalConstant(global) == llvm::True {
-                        if let Some(init) = llvm::LLVMGetInitializer(global) {
-                            if self.val_ty(init) == llty {
-                                const_llval = Some(init);
-                            }
+            if let Some(global) = llvm::LLVMIsAGlobalVariable(place.val.llval) {
+                if llvm::LLVMIsGlobalConstant(global) == llvm::True {
+                    if let Some(init) = llvm::LLVMGetInitializer(global) {
+                        if self.val_ty(init) == llty {
+                            const_llval = Some(init);
                         }
                     }
                 }
             }
+
             let llval = const_llval.unwrap_or_else(|| {
                 let load = self.load(llty, place.val.llval, place.val.align);
                 if let abi::BackendRepr::Scalar(scalar) = place.layout.backend_repr {
@@ -1721,7 +1717,7 @@ impl<'a, 'll, 'tcx> Builder<'a, 'll, 'tcx> {
             } else {
                 cfi::typeid_for_fnabi(self.tcx, fn_abi, options)
             };
-            let typeid_metadata = self.cx.typeid_metadata(typeid).unwrap();
+            let typeid_metadata = self.cx.create_metadata(typeid.as_bytes());
             let dbg_loc = self.get_dbg_loc();
 
             // Test whether the function pointer is associated with the type identifier using the