[Demangle][Rust] Parse array type

Reviewed By: dblaikie

Differential Revision: https://reviews.llvm.org/D102573

llvm/lib/Demangle/RustDemangle.cpp

@@ -421,14 +421,26 @@ void Demangler::printBasicType(BasicType Type) {
 //          | "D" <dyn-bounds> <lifetime> // dyn Trait<Assoc = X> + Send + 'a
 //          | <backref>                   // backref
 void Demangler::demangleType() {
-  char C = look();
-  BasicType Type;
-  if (parseBasicType(C, Type)) {
-    consume();
-    return printBasicType(Type);
-  }
+  size_t Start = Position;
 
-  demanglePath(InType::Yes);
+  char C = consume();
+  BasicType Type;
+  if (parseBasicType(C, Type))
+    return printBasicType(Type);
+
+  switch (C) {
+  case 'A':
+    print("[");
+    demangleType();
+    print("; ");
+    demangleConst();
+    print("]");
+    break;
+  default:
+    Position = Start;
+    demanglePath(InType::Yes);
+    break;
+  }
 }
 
 // <const> = <basic-type> <const-data>

llvm/test/Demangle/rust.test

@@ -155,6 +155,11 @@ CHECK: named::<name::Name>
 CHECK: named::<Name<>>
        _RIC5namedIC4NameEE
 
+; Types
+
+CHECK: types::<[u8; 0]>
+       _RIC5typesAhj0_E
+
 ; Integer constants. Test value demangling.
 
 CHECK: integer::<0>