2 files changed, 14 insertions, 0 deletions
diff --git a/lib/Target/ARM/Thumb1InstrInfo.cpp b/lib/Target/ARM/Thumb1InstrInfo.cpp
index 49645834e2de..05c98aab6f27 100644
--- a/lib/Target/ARM/Thumb1InstrInfo.cpp
+++ b/lib/Target/ARM/Thumb1InstrInfo.cpp
@@ -141,3 +141,16 @@ void Thumb1InstrInfo::expandLoadStackGuard(
   else
     expandLoadStackGuardBase(MI, ARM::tLDRLIT_ga_abs, ARM::tLDRi);
 }
+
+bool Thumb1InstrInfo::canCopyGluedNodeDuringSchedule(SDNode *N) const {
+  // In Thumb1 the scheduler may need to schedule a cross-copy between GPRS and CPSR
+  // but this is not always possible there, so allow the Scheduler to clone tADCS and tSBCS
+  // even if they have glue.
+  // FIXME. Actually implement the cross-copy where it is possible (post v6)
+  // because these copies entail more spilling.
+  unsigned Opcode = N->getMachineOpcode();
+  if (Opcode == ARM::tADCS || Opcode == ARM::tSBCS)
+    return true;
+
+  return false;
+}
diff --git a/lib/Target/ARM/Thumb1InstrInfo.h b/lib/Target/ARM/Thumb1InstrInfo.h
index e8d9a9c4ff14..9f04a3ed262f 100644
--- a/lib/Target/ARM/Thumb1InstrInfo.h
+++ b/lib/Target/ARM/Thumb1InstrInfo.h
@@ -53,6 +53,7 @@ public:
                             const TargetRegisterClass *RC,
                             const TargetRegisterInfo *TRI) const override;
 
+  bool canCopyGluedNodeDuringSchedule(SDNode *N) const override;
 private:
   void expandLoadStackGuard(MachineBasicBlock::iterator MI) const override;
 };