Fix integer undefined behavior due to signed left shift overflow in LLVM.

[oota-llvm.git] / lib / CodeGen / SelectionDAG / ScheduleDAGRRList.cpp

diff --git a/lib/CodeGen/SelectionDAG/ScheduleDAGRRList.cpp b/lib/CodeGen/SelectionDAG/ScheduleDAGRRList.cpp
index 0c92878b3116a149522ff9d09bf75770b0062d88..bf0a43785b70088e11b06ebd73c492edd6302e15 100644 (file)
--- a/lib/CodeGen/SelectionDAG/ScheduleDAGRRList.cpp
+++ b/lib/CodeGen/SelectionDAG/ScheduleDAGRRList.cpp
@@ -853,7 +853,7 @@ void ScheduleDAGRRList::UnscheduleNodeBottomUp(SUnit *SU) {
 }
 
 /// After backtracking, the hazard checker needs to be restored to a state
-/// corresponding the the current cycle.
+/// corresponding the current cycle.
 void ScheduleDAGRRList::RestoreHazardCheckerBottomUp() {
   HazardRec->Reset();
 
@@ -1182,7 +1182,7 @@ static void CheckForLiveRegDef(SUnit *SU, unsigned Reg,
                                SmallSet<unsigned, 4> &RegAdded,
                                SmallVector<unsigned, 4> &LRegs,
                                const TargetRegisterInfo *TRI) {
-  for (const uint16_t *AliasI = TRI->getOverlaps(Reg); *AliasI; ++AliasI) {
+  for (MCRegAliasIterator AliasI(Reg, TRI, true); AliasI.isValid(); ++AliasI) {
 
     // Check if Ref is live.
     if (!LiveRegDefs[*AliasI]) continue;
@@ -2331,22 +2331,21 @@ static int BUCompareLatency(SUnit *left, SUnit *right, bool checkPref,
   // and latency.
   if (!checkPref || (left->SchedulingPref == Sched::ILP ||
                      right->SchedulingPref == Sched::ILP)) {
-    if (DisableSchedCycles) {
+    // If neither instruction stalls (!LStall && !RStall) and HazardRecognizer
+    // is enabled, grouping instructions by cycle, then its height is already
+    // covered so only its depth matters. We also reach this point if both stall
+    // but have the same height.
+    if (!SPQ->getHazardRec()->isEnabled()) {
       if (LHeight != RHeight)
         return LHeight > RHeight ? 1 : -1;
     }
-    else {
-      // If neither instruction stalls (!LStall && !RStall) then
-      // its height is already covered so only its depth matters. We also reach
-      // this if both stall but have the same height.
-      int LDepth = left->getDepth() - LPenalty;
-      int RDepth = right->getDepth() - RPenalty;
-      if (LDepth != RDepth) {
-        DEBUG(dbgs() << "  Comparing latency of SU (" << left->NodeNum
-              << ") depth " << LDepth << " vs SU (" << right->NodeNum
-              << ") depth " << RDepth << "\n");
-        return LDepth < RDepth ? 1 : -1;
-      }
+    int LDepth = left->getDepth() - LPenalty;
+    int RDepth = right->getDepth() - RPenalty;
+    if (LDepth != RDepth) {
+      DEBUG(dbgs() << "  Comparing latency of SU (" << left->NodeNum
+            << ") depth " << LDepth << " vs SU (" << right->NodeNum
+            << ") depth " << RDepth << "\n");
+      return LDepth < RDepth ? 1 : -1;
     }
     if (left->Latency != right->Latency)
       return left->Latency > right->Latency ? 1 : -1;