1 files changed, 16 insertions, 2 deletions
diff --git a/llvm/lib/CodeGen/TargetSubtargetInfo.cpp b/llvm/lib/CodeGen/TargetSubtargetInfo.cpp
index c9f90b88cac..e34f9a1579d 100644
--- a/llvm/lib/CodeGen/TargetSubtargetInfo.cpp
+++ b/llvm/lib/CodeGen/TargetSubtargetInfo.cpp
@@ -88,6 +88,12 @@ std::string TargetSubtargetInfo::getSchedInfoStr(const MachineInstr &MI) const {
   TargetSchedModel TSchedModel;
   TSchedModel.init(this);
   unsigned Latency = TSchedModel.computeInstrLatency(&MI);
+
+  // Add extra latency due to forwarding delays.
+  const MCSchedClassDesc &SCDesc = *TSchedModel.resolveSchedClass(&MI);
+  Latency +=
+      MCSchedModel::getForwardingDelayCycles(getReadAdvanceEntries(SCDesc));
+
   double RThroughput = TSchedModel.computeReciprocalThroughput(&MI);
   return createSchedInfoStr(Latency, RThroughput);
 }
@@ -99,9 +105,17 @@ std::string TargetSubtargetInfo::getSchedInfoStr(MCInst const &MCI) const {
   TargetSchedModel TSchedModel;
   TSchedModel.init(this);
   unsigned Latency;
-  if (TSchedModel.hasInstrSchedModel())
+  if (TSchedModel.hasInstrSchedModel()) {
     Latency = TSchedModel.computeInstrLatency(MCI);
-  else if (TSchedModel.hasInstrItineraries()) {
+    // Add extra latency due to forwarding delays.
+    const MCSchedModel &SM = *TSchedModel.getMCSchedModel();
+    unsigned SClassID = getInstrInfo()->get(MCI.getOpcode()).getSchedClass();
+    while (SM.getSchedClassDesc(SClassID)->isVariant())
+      SClassID = resolveVariantSchedClass(SClassID, &MCI, SM.ProcID);
+    const MCSchedClassDesc &SCDesc = *SM.getSchedClassDesc(SClassID);  
+    Latency +=
+        MCSchedModel::getForwardingDelayCycles(getReadAdvanceEntries(SCDesc));
+  } else if (TSchedModel.hasInstrItineraries()) {
     auto *ItinData = TSchedModel.getInstrItineraries();
     Latency = ItinData->getStageLatency(
         getInstrInfo()->get(MCI.getOpcode()).getSchedClass());