llvm · Jan 16, 2018
diff --git a/‎llvm/lib/CodeGen/LiveDebugValues.cpp
+30-7 b/‎llvm/lib/CodeGen/LiveDebugValues.cpp
+30-7
@@ -426,16 +426,39 @@ bool LiveDebugValues::isSpillInstruction(const MachineInstr &MI,
         FrameInfo.isSpillSlotObjectIndex(FI)))
     return false;
 
-  // In a spill instruction generated by the InlineSpiller the spilled register
-  // has its kill flag set. Return false if we don't find such a register.
-  Reg = 0;
+  auto isKilledReg = [&](const MachineOperand MO, unsigned &Reg) {
+    if (!MO.isReg() || !MO.isUse()) {
+      Reg = 0;
+      return false;
+    }
+    Reg = MO.getReg();
+    return MO.isKill();
+  };
+
   for (const MachineOperand &MO : MI.operands()) {
-    if (MO.isReg() && MO.isUse() && MO.isKill()) {
-      Reg = MO.getReg();
-      break;
+    // In a spill instruction generated by the InlineSpiller the spilled
+    // register has its kill flag set.
+    if (isKilledReg(MO, Reg))
+      return true;
+    if (Reg != 0) {
+      // Check whether next instruction kills the spilled register.
+      // FIXME: Current solution does not cover search for killed register in
+      // bundles and instructions further down the chain.
+      auto NextI = std::next(MI.getIterator());
+      // Skip next instruction that points to basic block end iterator.
+      if (MI.getParent()->end() == NextI)
+        continue;
+      unsigned RegNext;
+      for (const MachineOperand &MONext : NextI->operands()) {
+        // Return true if we came across the register from the
+        // previous spill instruction that is killed in NextI.
+        if (isKilledReg(MONext, RegNext) && RegNext == Reg)
+          return true;
+      }
     }
   }
-  return Reg != 0;
+  // Return false if we didn't find spilled register.
+  return false;
 }
 
 /// A spilled register may indicate that we have to end the current range of