Add links to the reference and rust by example for asm! docs and lints

Author: Amanieu

core/src/lib.rs

@@ -374,13 +374,25 @@ pub mod arch {
     pub use crate::core_arch::arch::*;
 
     /// Inline assembly.
+    ///
+    /// Refer to [rust by example] for a usage guide and the [reference] for
+    /// detailed information about the syntax and available options.
+    ///
+    /// [rust by example]: https://doc.rust-lang.org/nightly/rust-by-example/unsafe/asm.html
+    /// [reference]: https://doc.rust-lang.org/nightly/reference/inline-assembly.html
     #[stable(feature = "asm", since = "1.59.0")]
     #[rustc_builtin_macro]
     pub macro asm("assembly template", $(operands,)* $(options($(option),*))?) {
         /* compiler built-in */
     }
 
     /// Module-level inline assembly.
+    ///
+    /// Refer to [rust by example] for a usage guide and the [reference] for
+    /// detailed information about the syntax and available options.
+    ///
+    /// [rust by example]: https://doc.rust-lang.org/nightly/rust-by-example/unsafe/asm.html
+    /// [reference]: https://doc.rust-lang.org/nightly/reference/inline-assembly.html
     #[stable(feature = "global_asm", since = "1.59.0")]
     #[rustc_builtin_macro]
     pub macro global_asm("assembly template", $(operands,)* $(options($(option),*))?) {