Generate interrupt dispatch code.

Useful for architectures that prefer or mandate dispatching interrupts in
software. Adds #[derive(Debug)] for printing readable interrupt names.

Author: dvc94ch

src/generate.rs

@@ -187,7 +187,8 @@ pub fn interrupt(
         interrupts.into_iter().map(|(_, v)| v).collect::<Vec<_>>();
     interrupts.sort_by_key(|i| i.value);
 
-    let mut arms = vec![];
+    let mut nr_arms = vec![];
+    let mut from_arms = vec![];
     let mut elements = vec![];
     let mut names = vec![];
     let mut variants = vec![];
@@ -223,10 +224,14 @@ pub fn interrupt(
             #name_uc,
         });
 
-        arms.push(quote! {
+        nr_arms.push(quote! {
             Interrupt::#name_uc => #value,
         });
 
+        from_arms.push(quote! {
+            #value => Interrupt::#name_uc,
+        });
+
         elements.push(quote!(Some(#name_uc)));
         names.push(name_uc);
     }
@@ -335,6 +340,7 @@ pub fn interrupt(
 
     mod_items.push(quote! {
         /// Enumeration of all the interrupts
+        #[derive(Debug)]
         pub enum Interrupt {
             #(#variants)*
         }
@@ -343,7 +349,17 @@ pub fn interrupt(
             #[inline]
             fn nr(&self) -> u8 {
                 match *self {
-                    #(#arms)*
+                    #(#nr_arms)*
+                }
+            }
+        }
+
+        impl Interrupt {
+            #[inline(always)]
+            pub fn from(nr: u8) -> Interrupt {
+                match nr {
+                    #(#from_arms)*
+                    _ => unreachable!(),
                 }
             }
         }