1 files changed, 12 insertions, 2 deletions
diff --git a/llvm/lib/Target/PowerPC/PPCFastISel.cpp b/llvm/lib/Target/PowerPC/PPCFastISel.cpp
index 9dd9baa7580..fbd7b6d7f1c 100644
--- a/llvm/lib/Target/PowerPC/PPCFastISel.cpp
+++ b/llvm/lib/Target/PowerPC/PPCFastISel.cpp
@@ -675,8 +675,18 @@ bool PPCFastISel::PPCEmitStore(MVT VT, unsigned SrcReg, Address &Addr) {
       case PPC::STFS: Opc = PPC::STFSX; break;
       case PPC::STFD: Opc = IsVSFRC ? PPC::STXSDX : PPC::STFDX; break;
     }
-    BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DbgLoc, TII.get(Opc))
-      .addReg(SrcReg).addReg(Addr.Base.Reg).addReg(IndexReg);
+
+    auto MIB = BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DbgLoc, TII.get(Opc))
+        .addReg(SrcReg);
+
+    // If we have an index register defined we use it in the store inst,
+    // otherwise we use X0 as base as it makes the vector instructions to
+    // use zero in the computation of the effective address regardless the
+    // content of the register.
+    if (IndexReg)
+      MIB.addReg(Addr.Base.Reg).addReg(IndexReg);
+    else
+      MIB.addReg(PPC::ZERO8).addReg(Addr.Base.Reg);
   }
 
   return true;