From 8ddd9d5b2bee3ccdb36aee4423ca4443d7b3dc32 Mon Sep 17 00:00:00 2001
From: Andrew Trick <atrick@apple.com>
Date: Thu, 24 May 2012 23:11:17 +0000
Subject: [PATCH] misched: Use the same scheduling heuristics with
 -misched-topdown/bottomup.

(except the part about choosing direction)

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@157437 91177308-0d34-0410-b5e6-96231b3b80d8
---
 lib/CodeGen/MachineScheduler.cpp | 18 ++++++++++++++++--
 1 file changed, 16 insertions(+), 2 deletions(-)

diff --git a/lib/CodeGen/MachineScheduler.cpp b/lib/CodeGen/MachineScheduler.cpp
index 78a5b8d8cd5..662b16fa0a0 100644
--- a/lib/CodeGen/MachineScheduler.cpp
+++ b/lib/CodeGen/MachineScheduler.cpp
@@ -1168,11 +1168,25 @@ SUnit *ConvergingScheduler::pickNode(bool &IsTopNode) {
   }
   SUnit *SU;
   if (ForceTopDown) {
-    SU = DAG->getSUnit(DAG->top());
+    SU = Top.pickOnlyChoice();
+    if (!SU) {
+      SchedCandidate TopCand;
+      CandResult TopResult =
+        pickNodeFromQueue(Top.Available, DAG->getTopRPTracker(), TopCand);
+      assert(TopResult != NoCand && "failed to find the first candidate");
+      SU = TopCand.SU;
+    }
     IsTopNode = true;
   }
   else if (ForceBottomUp) {
-    SU = DAG->getSUnit(priorNonDebug(DAG->bottom(), DAG->top()));
+    SU = Bot.pickOnlyChoice();
+    if (!SU) {
+      SchedCandidate BotCand;
+      CandResult BotResult =
+        pickNodeFromQueue(Bot.Available, DAG->getBotRPTracker(), BotCand);
+      assert(BotResult != NoCand && "failed to find the first candidate");
+      SU = BotCand.SU;
+    }
     IsTopNode = false;
   }
   else {