diff --git a/llvm/lib/Target/X86/X86FastISel.cpp b/llvm/lib/Target/X86/X86FastISel.cpp
--- a/llvm/lib/Target/X86/X86FastISel.cpp
+++ b/llvm/lib/Target/X86/X86FastISel.cpp
@@ -1082,13 +1082,30 @@
 
   // If all else fails, try to materialize the value in a register.
   if (!AM.GV || !Subtarget->isPICStyleRIPRel()) {
+    auto GetCallRegForValue = [this](const Value *V) {
+      auto Reg = getRegForValue(V);
+
+      // In 64-bit mode, we need a 64-bit register even if pointers are 32 bits.
+      if (Reg && Subtarget->isTarget64BitILP32()) {
+        auto ExtReg = createResultReg(&X86::GR64RegClass);
+        BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DbgLoc,
+                TII.get(TargetOpcode::SUBREG_TO_REG), ExtReg)
+            .addImm(0)
+            .addReg(Reg)
+            .addImm(X86::sub_32bit);
+        Reg = ExtReg;
+      }
+
+      return Reg;
+    };
+
     if (AM.Base.Reg == 0) {
-      AM.Base.Reg = getRegForValue(V);
+      AM.Base.Reg = GetCallRegForValue(V);
       return AM.Base.Reg != 0;
     }
     if (AM.IndexReg == 0) {
       assert(AM.Scale == 1 && "Scale with no index!");
-      AM.IndexReg = getRegForValue(V);
+      AM.IndexReg = GetCallRegForValue(V);
       return AM.IndexReg != 0;
     }
   }