1 files changed, 2 insertions, 0 deletions
diff --git a/lib/CodeGen/RegAllocFast.cpp b/lib/CodeGen/RegAllocFast.cpp
index 30ecea0018..7bb849ef54 100644
--- a/lib/CodeGen/RegAllocFast.cpp
+++ b/lib/CodeGen/RegAllocFast.cpp
@@ -442,6 +442,8 @@ unsigned RAFast::calcSpillCost(unsigned PhysReg) const {
   unsigned Cost = 0;
   for (const unsigned *AS = TRI->getAliasSet(PhysReg);
        unsigned Alias = *AS; ++AS) {
+    if (UsedInInstr.test(Alias))
+      return spillImpossible;
     switch (unsigned VirtReg = PhysRegState[Alias]) {
     case regDisabled:
       break;