Fix PR3241: Currently EmitCopyFromReg emits a copy from the physical register to a virtual register unless it requires an expensive cross class copy. That means we are only treating "expensive to copy" register dependency as physical register dependency.

Also future proof the scheduler to handle "normal" physical register dependencies. The code is not exercised yet.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@62074 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 7 insertions, 4 deletions

diff --git a/lib/CodeGen/SelectionDAG/ScheduleDAGSDNodesEmit.cpp b/lib/CodeGen/SelectionDAG/ScheduleDAGSDNodesEmit.cpp
index ebe084d811..d617965158 100644
--- a/lib/CodeGen/SelectionDAG/ScheduleDAGSDNodesEmit.cpp
+++ b/lib/CodeGen/SelectionDAG/ScheduleDAGSDNodesEmit.cpp
@@ -629,6 +629,12 @@ MachineBasicBlock *ScheduleDAGSDNodes::EmitSchedule() {
 
     // For pre-regalloc scheduling, create instructions corresponding to the
     // SDNode and any flagged SDNodes and append them to the block.
+    if (!SU->getNode()) {
+      // Emit a copy.
+      EmitPhysRegCopy(SU, CopyVRBaseMap);
+      continue;
+    }
+
     SmallVector<SDNode *, 4> FlaggedNodes;
     for (SDNode *N = SU->getNode()->getFlaggedNode(); N; N = N->getFlaggedNode())
       FlaggedNodes.push_back(N);
@@ -636,10 +642,7 @@ MachineBasicBlock *ScheduleDAGSDNodes::EmitSchedule() {
       EmitNode(FlaggedNodes.back(), SU->OrigNode != SU, VRBaseMap);
       FlaggedNodes.pop_back();
     }
-    if (!SU->getNode())
-      EmitCrossRCCopy(SU, CopyVRBaseMap);
-    else
-      EmitNode(SU->getNode(), SU->OrigNode != SU, VRBaseMap);
+    EmitNode(SU->getNode(), SU->OrigNode != SU, VRBaseMap);
   }
 
   return BB;