diff --git a/lib/Target/ARM/ARMFastISel.cpp b/lib/Target/ARM/ARMFastISel.cpp
index cc9d42a86c0..bd0a64c542c 100644
--- a/lib/Target/ARM/ARMFastISel.cpp
+++ b/lib/Target/ARM/ARMFastISel.cpp
@@ -2207,10 +2207,11 @@ bool ARMFastISel::SelectCall(const Instruction *I,
   SmallVector<unsigned, 8> ArgRegs;
   SmallVector<MVT, 8> ArgVTs;
   SmallVector<ISD::ArgFlagsTy, 8> ArgFlags;
-  Args.reserve(CS.arg_size());
-  ArgRegs.reserve(CS.arg_size());
-  ArgVTs.reserve(CS.arg_size());
-  ArgFlags.reserve(CS.arg_size());
+  unsigned arg_size = CS.arg_size();
+  Args.reserve(arg_size);
+  ArgRegs.reserve(arg_size);
+  ArgVTs.reserve(arg_size);
+  ArgFlags.reserve(arg_size);
   for (ImmutableCallSite::arg_iterator i = CS.arg_begin(), e = CS.arg_end();
        i != e; ++i) {
     // If we're lowering a memory intrinsic instead of a regular call, skip the