From: Pat Gavlin <pagavlin@microsoft.com>
Date: Wed, 26 Jul 2017 00:39:21 +0000 (-0700)
Subject: Set `BBF_RUN_RARELY` for a scratch first BB if called count is 0.
X-Git-Tag: accepted/tizen/base/20180629.140029~1083^2~65^2
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=af50f816d24cef5ff639db48722851c48e43b058;p=platform%2Fupstream%2Fcoreclr.git

Set `BBF_RUN_RARELY` for a scratch first BB if called count is 0.

Just what it says on the tin.

Fixes VSO 469624.
---

diff --git a/src/jit/flowgraph.cpp b/src/jit/flowgraph.cpp
index 5dab6bb..0c8a28e 100644
--- a/src/jit/flowgraph.cpp
+++ b/src/jit/flowgraph.cpp
@@ -12836,6 +12836,10 @@ void Compiler::fgComputeEdgeWeights()
         if (fgFirstBBisScratch())
         {
             fgFirstBB->setBBProfileWeight(fgCalledCount);
+            if (fgFirstBB->bbWeight == 0)
+            {
+                fgFirstBB->bbFlags |= BBF_RUN_RARELY;
+            }
         }
 
 #if DEBUG