From: Christopher Dykes <cdykes@fb.com>
Date: Tue, 24 May 2016 00:30:29 +0000 (-0700)
Subject: Support folly::assume under MSVC
X-Git-Tag: 2016.07.26~209
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=0558fb60f996b14a826e70170781b5afcde5f5bf;p=folly.git

Support folly::assume under MSVC

Summary: Actually __assume when we assume.

Reviewed By: meyering

Differential Revision: D3336033

fbshipit-source-id: 6c931e9f832dd1d861d03e3ad8e308f612522401
---

diff --git a/folly/Assume.h b/folly/Assume.h
index 7c50a679..8f807433 100644
--- a/folly/Assume.h
+++ b/folly/Assume.h
@@ -38,6 +38,8 @@ FOLLY_ALWAYS_INLINE void assume(bool cond) {
   __builtin_assume(cond);
 #elif defined(__GNUC__)
   if (!cond) { __builtin_unreachable(); }
+#elif defined(_MSC_VER)
+  __assume(cond);
 #else
   // Do nothing.
 #endif