Rollup of 7 pull requests

src/bootstrap/test.rs

@@ -553,7 +553,7 @@ impl Step for Clippy {
 
         builder.add_rustc_lib_path(compiler, &mut cargo);
 
-        try_run(builder, &mut cargo.into());
+        builder.run(&mut cargo.into());
     }
 }
 

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

@@ -201,7 +201,7 @@ fn mul(a: u64, b: u64) -> u128 {
         );
     }
 
-    (hi as u128) << 64 + lo as u128
+    ((hi as u128) << 64) + lo as u128
 }
 ```
 
@@ -382,7 +382,9 @@ The macro will initially be supported only on ARM, AArch64, x86, x86-64 and RISC
 
 The assembler template uses the same syntax as [format strings][format-syntax] (i.e. placeholders are specified by curly braces). The corresponding arguments are accessed in order, by index, or by name. However, implicit named arguments (introduced by [RFC #2795][rfc-2795]) are not supported.
 
-As with format strings, named arguments must appear after positional arguments. Explicit register operands must appear at the end of the operand list, after any named arguments if any. Explicit register operands cannot be used by placeholders in the template string. All other operands must appear at least once in the template string, otherwise a compiler error is generated.
+As with format strings, named arguments must appear after positional arguments. Explicit register operands must appear at the end of the operand list, after named arguments if any.
+
+Explicit register operands cannot be used by placeholders in the template string. All other named and positional operands must appear at least once in the template string, otherwise a compiler error is generated.
 
 The exact assembly code syntax is target-specific and opaque to the compiler except for the way operands are substituted into the template string to form the code passed to the assembler.
 

src/librustc_ast/ast.rs

@@ -1174,7 +1174,9 @@ pub enum ExprKind {
     /// and the remaining elements are the rest of the arguments.
     /// Thus, `x.foo::<Bar, Baz>(a, b, c, d)` is represented as
     /// `ExprKind::MethodCall(PathSegment { foo, [Bar, Baz] }, [x, a, b, c, d])`.
-    MethodCall(PathSegment, Vec<P<Expr>>),
+    /// This `Span` is the span of the function, without the dot and receiver
+    /// (e.g. `foo(a, b)` in `x.foo(a, b)`
+    MethodCall(PathSegment, Vec<P<Expr>>, Span),
     /// A tuple (e.g., `(a, b, c, d)`).
     Tup(Vec<P<Expr>>),
     /// A binary operation (e.g., `a + b`, `a * b`).

src/librustc_ast/mut_visit.rs

@@ -1111,11 +1111,12 @@ pub fn noop_visit_expr<T: MutVisitor>(
             vis.visit_expr(f);
             visit_exprs(args, vis);
         }
-        ExprKind::MethodCall(PathSegment { ident, id, args }, exprs) => {
+        ExprKind::MethodCall(PathSegment { ident, id, args }, exprs, span) => {
             vis.visit_ident(ident);
             vis.visit_id(id);
             visit_opt(args, |args| vis.visit_generic_args(args));
             visit_exprs(exprs, vis);
+            vis.visit_span(span);
         }
         ExprKind::Binary(_binop, lhs, rhs) => {
             vis.visit_expr(lhs);

src/librustc_ast/util/parser.rs

@@ -394,7 +394,7 @@ pub fn contains_exterior_struct_lit(value: &ast::Expr) -> bool {
             contains_exterior_struct_lit(&x)
         }
 
-        ast::ExprKind::MethodCall(.., ref exprs) => {
+        ast::ExprKind::MethodCall(.., ref exprs, _) => {
             // X { y: 1 }.bar(...)
             contains_exterior_struct_lit(&exprs[0])
         }

src/librustc_ast/visit.rs

@@ -726,7 +726,7 @@ pub fn walk_expr<'a, V: Visitor<'a>>(visitor: &mut V, expression: &'a Expr) {
             visitor.visit_expr(callee_expression);
             walk_list!(visitor, visit_expr, arguments);
         }
-        ExprKind::MethodCall(ref segment, ref arguments) => {
+        ExprKind::MethodCall(ref segment, ref arguments, _span) => {
             visitor.visit_path_segment(expression.span, segment);
             walk_list!(visitor, visit_expr, arguments);
         }

src/librustc_ast_lowering/expr.rs

@@ -39,7 +39,7 @@ impl<'hir> LoweringContext<'_, 'hir> {
                     let f = self.lower_expr(f);
                     hir::ExprKind::Call(f, self.lower_exprs(args))
                 }
-                ExprKind::MethodCall(ref seg, ref args) => {
+                ExprKind::MethodCall(ref seg, ref args, span) => {
                     let hir_seg = self.arena.alloc(self.lower_path_segment(
                         e.span,
                         seg,
@@ -50,7 +50,7 @@ impl<'hir> LoweringContext<'_, 'hir> {
                         None,
                     ));
                     let args = self.lower_exprs(args);
-                    hir::ExprKind::MethodCall(hir_seg, seg.ident.span, args)
+                    hir::ExprKind::MethodCall(hir_seg, seg.ident.span, args, span)
                 }
                 ExprKind::Binary(binop, ref lhs, ref rhs) => {
                     let binop = self.lower_binop(binop);

src/librustc_ast_pretty/pprust.rs

@@ -1818,7 +1818,7 @@ impl<'a> State<'a> {
             ast::ExprKind::Call(ref func, ref args) => {
                 self.print_expr_call(func, &args[..]);
             }
-            ast::ExprKind::MethodCall(ref segment, ref args) => {
+            ast::ExprKind::MethodCall(ref segment, ref args, _) => {
                 self.print_expr_method_call(segment, &args[..]);
             }
             ast::ExprKind::Binary(op, ref lhs, ref rhs) => {

src/librustc_builtin_macros/asm.rs

@@ -391,7 +391,8 @@ fn expand_preparsed_asm(ecx: &mut ExtCtxt<'_>, sp: Span, args: AsmArgs) -> P<ast
         used[*pos] = true;
     }
 
-    let named_pos: FxHashSet<usize> = args.named_args.values().cloned().collect();
+    let named_pos: FxHashMap<usize, Symbol> =
+        args.named_args.iter().map(|(&sym, &idx)| (idx, sym)).collect();
     let mut arg_spans = parser.arg_places.iter().map(|span| template_span.from_inner(*span));
     let mut template = vec![];
     for piece in unverified_pieces {
@@ -405,7 +406,7 @@ fn expand_preparsed_asm(ecx: &mut ExtCtxt<'_>, sp: Span, args: AsmArgs) -> P<ast
                 let operand_idx = match arg.position {
                     parse::ArgumentIs(idx) | parse::ArgumentImplicitlyIs(idx) => {
                         if idx >= args.operands.len()
-                            || named_pos.contains(&idx)
+                            || named_pos.contains_key(&idx)
                             || args.reg_args.contains(&idx)
                         {
                             let msg = format!("invalid reference to argument at index {}", idx);
@@ -426,7 +427,7 @@ fn expand_preparsed_asm(ecx: &mut ExtCtxt<'_>, sp: Span, args: AsmArgs) -> P<ast
                             };
                             err.note(&msg);
 
-                            if named_pos.contains(&idx) {
+                            if named_pos.contains_key(&idx) {
                                 err.span_label(args.operands[idx].1, "named argument");
                                 err.span_note(
                                     args.operands[idx].1,
@@ -480,27 +481,31 @@ fn expand_preparsed_asm(ecx: &mut ExtCtxt<'_>, sp: Span, args: AsmArgs) -> P<ast
         }
     }
 
-    let operands = args.operands;
-    let unused_operands: Vec<_> = used
-        .into_iter()
-        .enumerate()
-        .filter(|&(_, used)| !used)
-        .map(|(idx, _)| {
-            if named_pos.contains(&idx) {
-                // named argument
-                (operands[idx].1, "named argument never used")
+    let mut unused_operands = vec![];
+    let mut help_str = String::new();
+    for (idx, used) in used.into_iter().enumerate() {
+        if !used {
+            let msg = if let Some(sym) = named_pos.get(&idx) {
+                help_str.push_str(&format!(" {{{}}}", sym));
+                "named argument never used"
             } else {
-                // positional argument
-                (operands[idx].1, "argument never used")
-            }
-        })
-        .collect();
+                help_str.push_str(&format!(" {{{}}}", idx));
+                "argument never used"
+            };
+            unused_operands.push((args.operands[idx].1, msg));
+        }
+    }
     match unused_operands.len() {
         0 => {}
         1 => {
             let (sp, msg) = unused_operands.into_iter().next().unwrap();
             let mut err = ecx.struct_span_err(sp, msg);
             err.span_label(sp, msg);
+            err.help(&format!(
+                "if this argument is intentionally unused, \
+                 consider using it in an asm comment: `\"/*{} */\"`",
+                help_str
+            ));
             err.emit();
         }
         _ => {
@@ -511,6 +516,11 @@ fn expand_preparsed_asm(ecx: &mut ExtCtxt<'_>, sp: Span, args: AsmArgs) -> P<ast
             for (sp, msg) in unused_operands {
                 err.span_label(sp, msg);
             }
+            err.help(&format!(
+                "if these arguments are intentionally unused, \
+                 consider using them in an asm comment: `\"/*{} */\"`",
+                help_str
+            ));
             err.emit();
         }
     }
@@ -521,7 +531,8 @@ fn expand_preparsed_asm(ecx: &mut ExtCtxt<'_>, sp: Span, args: AsmArgs) -> P<ast
         parser.line_spans.iter().map(|span| template_span.from_inner(*span)).collect()
     };
 
-    let inline_asm = ast::InlineAsm { template, operands, options: args.options, line_spans };
+    let inline_asm =
+        ast::InlineAsm { template, operands: args.operands, options: args.options, line_spans };
     P(ast::Expr {
         id: ast::DUMMY_NODE_ID,
         kind: ast::ExprKind::InlineAsm(P(inline_asm)),

src/librustc_codegen_llvm/back/write.rs

@@ -16,7 +16,7 @@ use rustc_codegen_ssa::back::write::{BitcodeSection, CodegenContext, EmitObj, Mo
 use rustc_codegen_ssa::traits::*;
 use rustc_codegen_ssa::{CompiledModule, ModuleCodegen};
 use rustc_data_structures::small_c_str::SmallCStr;
-use rustc_errors::{FatalError, Handler};
+use rustc_errors::{FatalError, Handler, Level};
 use rustc_fs_util::{link_or_copy, path_to_c_string};
 use rustc_hir::def_id::LOCAL_CRATE;
 use rustc_middle::bug;
@@ -242,6 +242,7 @@ impl<'a> Drop for DiagnosticHandlers<'a> {
 fn report_inline_asm(
     cgcx: &CodegenContext<LlvmCodegenBackend>,
     msg: String,
+    level: llvm::DiagnosticLevel,
     mut cookie: c_uint,
     source: Option<(String, Vec<InnerSpan>)>,
 ) {
@@ -251,7 +252,12 @@ fn report_inline_asm(
     if matches!(cgcx.lto, Lto::Fat | Lto::Thin) {
         cookie = 0;
     }
-    cgcx.diag_emitter.inline_asm_error(cookie as u32, msg, source);
+    let level = match level {
+        llvm::DiagnosticLevel::Error => Level::Error,
+        llvm::DiagnosticLevel::Warning => Level::Warning,
+        llvm::DiagnosticLevel::Note | llvm::DiagnosticLevel::Remark => Level::Note,
+    };
+    cgcx.diag_emitter.inline_asm_error(cookie as u32, msg, level, source);
 }
 
 unsafe extern "C" fn inline_asm_handler(diag: &SMDiagnostic, user: *const c_void, cookie: c_uint) {
@@ -264,6 +270,7 @@ unsafe extern "C" fn inline_asm_handler(diag: &SMDiagnostic, user: *const c_void
     // diagnostics.
     let mut have_source = false;
     let mut buffer = String::new();
+    let mut level = llvm::DiagnosticLevel::Error;
     let mut loc = 0;
     let mut ranges = [0; 8];
     let mut num_ranges = ranges.len() / 2;
@@ -273,6 +280,7 @@ unsafe extern "C" fn inline_asm_handler(diag: &SMDiagnostic, user: *const c_void
                 diag,
                 msg,
                 buffer,
+                &mut level,
                 &mut loc,
                 ranges.as_mut_ptr(),
                 &mut num_ranges,
@@ -290,7 +298,7 @@ unsafe extern "C" fn inline_asm_handler(diag: &SMDiagnostic, user: *const c_void
         (buffer, spans)
     });
 
-    report_inline_asm(cgcx, msg, cookie, source);
+    report_inline_asm(cgcx, msg, level, cookie, source);
 }
 
 unsafe extern "C" fn diagnostic_handler(info: &DiagnosticInfo, user: *mut c_void) {
@@ -301,7 +309,13 @@ unsafe extern "C" fn diagnostic_handler(info: &DiagnosticInfo, user: *mut c_void
 
     match llvm::diagnostic::Diagnostic::unpack(info) {
         llvm::diagnostic::InlineAsm(inline) => {
-            report_inline_asm(cgcx, llvm::twine_to_string(inline.message), inline.cookie, None);
+            report_inline_asm(
+                cgcx,
+                llvm::twine_to_string(inline.message),
+                inline.level,
+                inline.cookie,
+                None,
+            );
         }
 
         llvm::diagnostic::Optimization(opt) => {

src/librustc_codegen_llvm/llvm/diagnostic.rs

@@ -88,6 +88,7 @@ impl OptimizationDiagnostic<'ll> {
 
 #[derive(Copy, Clone)]
 pub struct InlineAsmDiagnostic<'ll> {
+    pub level: super::DiagnosticLevel,
     pub cookie: c_uint,
     pub message: &'ll Twine,
     pub instruction: Option<&'ll Value>,
@@ -98,10 +99,17 @@ impl InlineAsmDiagnostic<'ll> {
         let mut cookie = 0;
         let mut message = None;
         let mut instruction = None;
+        let mut level = super::DiagnosticLevel::Error;
 
-        super::LLVMRustUnpackInlineAsmDiagnostic(di, &mut cookie, &mut message, &mut instruction);
+        super::LLVMRustUnpackInlineAsmDiagnostic(
+            di,
+            &mut level,
+            &mut cookie,
+            &mut message,
+            &mut instruction,
+        );
 
-        InlineAsmDiagnostic { cookie, message: message.unwrap(), instruction }
+        InlineAsmDiagnostic { level, cookie, message: message.unwrap(), instruction }
     }
 }
 

src/librustc_codegen_llvm/llvm/ffi.rs

@@ -489,6 +489,17 @@ pub enum DiagnosticKind {
     Linker,
 }
 
+/// LLVMRustDiagnosticLevel
+#[derive(Copy, Clone)]
+#[repr(C)]
+#[allow(dead_code)] // Variants constructed by C++.
+pub enum DiagnosticLevel {
+    Error,
+    Warning,
+    Note,
+    Remark,
+}
+
 /// LLVMRustArchiveKind
 #[derive(Copy, Clone)]
 #[repr(C)]
@@ -2054,6 +2065,7 @@ extern "C" {
 
     pub fn LLVMRustUnpackInlineAsmDiagnostic(
         DI: &'a DiagnosticInfo,
+        level_out: &mut DiagnosticLevel,
         cookie_out: &mut c_uint,
         message_out: &mut Option<&'a Twine>,
         instruction_out: &mut Option<&'a Value>,
@@ -2074,6 +2086,7 @@ extern "C" {
         d: &SMDiagnostic,
         message_out: &RustString,
         buffer_out: &RustString,
+        level_out: &mut DiagnosticLevel,
         loc_out: &mut c_uint,
         ranges_out: *mut c_uint,
         num_ranges: &mut usize,

src/librustc_codegen_ssa/back/write.rs

@@ -1551,7 +1551,7 @@ fn spawn_work<B: ExtraBackendMethods>(cgcx: CodegenContext<B>, work: WorkItem<B>
 
 enum SharedEmitterMessage {
     Diagnostic(Diagnostic),
-    InlineAsmError(u32, String, Option<(String, Vec<InnerSpan>)>),
+    InlineAsmError(u32, String, Level, Option<(String, Vec<InnerSpan>)>),
     AbortIfErrors,
     Fatal(String),
 }
@@ -1576,9 +1576,10 @@ impl SharedEmitter {
         &self,
         cookie: u32,
         msg: String,
+        level: Level,
         source: Option<(String, Vec<InnerSpan>)>,
     ) {
-        drop(self.sender.send(SharedEmitterMessage::InlineAsmError(cookie, msg, source)));
+        drop(self.sender.send(SharedEmitterMessage::InlineAsmError(cookie, msg, level, source)));
     }
 
     pub fn fatal(&self, msg: &str) {
@@ -1631,16 +1632,21 @@ impl SharedEmitterMain {
                     }
                     handler.emit_diagnostic(&d);
                 }
-                Ok(SharedEmitterMessage::InlineAsmError(cookie, msg, source)) => {
+                Ok(SharedEmitterMessage::InlineAsmError(cookie, msg, level, source)) => {
                     let msg = msg.strip_prefix("error: ").unwrap_or(&msg);
 
+                    let mut err = match level {
+                        Level::Error => sess.struct_err(&msg),
+                        Level::Warning => sess.struct_warn(&msg),
+                        Level::Note => sess.struct_note_without_error(&msg),
+                        _ => bug!("Invalid inline asm diagnostic level"),
+                    };
+
                     // If the cookie is 0 then we don't have span information.
-                    let mut err = if cookie == 0 {
-                        sess.struct_err(&msg)
-                    } else {
+                    if cookie != 0 {
                         let pos = BytePos::from_u32(cookie);
                         let span = Span::with_root_ctxt(pos, pos);
-                        sess.struct_span_err(span, &msg)
+                        err.set_span(span);
                     };
 
                     // Point to the generated assembly if it is available.