From 51eea8b89dd715763ccd65fc722c16f0be8ef1c0 Mon Sep 17 00:00:00 2001
From: Dan Gohman <sunfish@mozilla.com>
Date: Fri, 23 Mar 2018 12:46:23 -0700
Subject: [PATCH] Add some comments noting unimplemented features.

While use of these features will trigger an `unimplemented!()`, it is
nice to let users know in advance about features which aren't yet
implemented.
---
 lib/cretonne/src/ir/heap.rs   | 2 ++
 lib/cretonne/src/isa/stack.rs | 2 ++
 2 files changed, 4 insertions(+)

diff --git a/lib/cretonne/src/ir/heap.rs b/lib/cretonne/src/ir/heap.rs
index 7920ec344a..e2a5366a1a 100644
--- a/lib/cretonne/src/ir/heap.rs
+++ b/lib/cretonne/src/ir/heap.rs
@@ -25,6 +25,8 @@ pub struct HeapData {
 #[derive(Clone)]
 pub enum HeapBase {
     /// The heap base lives in a reserved register.
+    ///
+    /// This feature is not yet implemented.
     ReservedReg,
 
     /// The heap base is in a global variable.
diff --git a/lib/cretonne/src/isa/stack.rs b/lib/cretonne/src/isa/stack.rs
index e8a9b6981b..9e09a52808 100644
--- a/lib/cretonne/src/isa/stack.rs
+++ b/lib/cretonne/src/isa/stack.rs
@@ -68,6 +68,8 @@ pub enum StackBase {
     FP = 1,
 
     /// Use an explicit zone pointer in a general-purpose register.
+    ///
+    /// This feature is not yet implemented.
     Zone = 2,
 }