Set trunc store action to Expand for all X86 targets.

[oota-llvm.git] / lib / CodeGen / ScheduleDAGInstrs.cpp

diff --git a/lib/CodeGen/ScheduleDAGInstrs.cpp b/lib/CodeGen/ScheduleDAGInstrs.cpp
index 179dca4e455ac44f7ff33d22472303cf0578ca90..08edf070460df5cca5114c1cb74fa8308d1f8817 100644 (file)
--- a/lib/CodeGen/ScheduleDAGInstrs.cpp
+++ b/lib/CodeGen/ScheduleDAGInstrs.cpp
@@ -511,9 +511,18 @@ static inline bool isUnsafeMemoryObject(MachineInstr *MI,
 static bool MIsNeedChainEdge(AliasAnalysis *AA, const MachineFrameInfo *MFI,
                              MachineInstr *MIa,
                              MachineInstr *MIb) {
+  const MachineFunction *MF = MIa->getParent()->getParent();
+  const TargetInstrInfo *TII = MF->getSubtarget().getInstrInfo();
+
   // Cover a trivial case - no edge is need to itself.
   if (MIa == MIb)
     return false;
+ 
+  // Let the target decide if memory accesses cannot possibly overlap.
+  if ((MIa->mayLoad() || MIa->mayStore()) &&
+      (MIb->mayLoad() || MIb->mayStore()))
+    if (TII->areMemAccessesTriviallyDisjoint(MIa, MIb, AA))
+      return false;
 
   // FIXME: Need to handle multiple memory operands to support all targets.
   if (!MIa->hasOneMemOperand() || !MIb->hasOneMemOperand())