Swap a few APIs to reduce sign and implicit truncations required to work with it

[folly.git] / folly / DiscriminatedPtr.h

diff --git a/folly/DiscriminatedPtr.h b/folly/DiscriminatedPtr.h
index 2f76a658b22f0feb6782a6fa0e3c565688f9b475..7fda96b914c7815c08b323525864a2517c2a13ee 100644 (file)
--- a/folly/DiscriminatedPtr.h
+++ b/folly/DiscriminatedPtr.h
@@ -1,5 +1,5 @@
 /*
- * Copyright 2016 Facebook, Inc.
+ * Copyright 2017 Facebook, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -24,8 +24,7 @@
  * @author Tudor Bosman (tudorb@fb.com)
  */
 
-#ifndef FOLLY_DISCRIMINATEDPTR_H_
-#define FOLLY_DISCRIMINATEDPTR_H_
+#pragma once
 
 #include <limits>
 #include <stdexcept>
@@ -34,8 +33,8 @@
 #include <folly/Portability.h>
 #include <folly/detail/DiscriminatedPtrDetail.h>
 
-#if !FOLLY_X64 && !FOLLY_PPC64
-# error "DiscriminatedPtr is x64 and ppc64 specific code."
+#if !FOLLY_X64 && !FOLLY_A64 && !FOLLY_PPC64
+# error "DiscriminatedPtr is x64, arm64 and ppc64 specific code."
 #endif
 
 namespace folly {
@@ -191,8 +190,8 @@ class DiscriminatedPtr {
    * Get the 1-based type index of T in Types.
    */
   template <typename T>
-  size_t typeIndex() const {
-    return dptr_detail::GetTypeIndex<T, Types...>::value;
+  uint16_t typeIndex() const {
+    return uint16_t(dptr_detail::GetTypeIndex<T, Types...>::value);
   }
 
   uint16_t index() const { return data_ >> 48; }
@@ -217,5 +216,3 @@ class DiscriminatedPtr {
 };
 
 }  // namespace folly
-
-#endif /* FOLLY_DISCRIMINATEDPTR_H_ */