diff --git a/lib/Target/ARM/ARMISelLowering.cpp b/lib/Target/ARM/ARMISelLowering.cpp
index c1ed4a64283..03ca1999b8e 100644
--- a/lib/Target/ARM/ARMISelLowering.cpp
+++ b/lib/Target/ARM/ARMISelLowering.cpp
@@ -1570,7 +1570,8 @@ ARMTargetLowering::LowerCall(TargetLowering::CallLoweringInfo &CLI,
           SDValue AddArg = DAG.getNode(ISD::ADD, dl, PtrVT, Arg, Const);
           SDValue Load = DAG.getLoad(PtrVT, dl, Chain, AddArg,
                                      MachinePointerInfo(),
-                                     false, false, false, 0);
+                                     false, false, false,
+                                     DAG.InferPtrAlignment(AddArg));
           MemOpChains.push_back(Load.getValue(1));
           RegsToPass.push_back(std::make_pair(j, Load));
         }
diff --git a/test/CodeGen/ARM/byval_load_align.ll b/test/CodeGen/ARM/byval_load_align.ll
new file mode 100644
index 00000000000..2c0910c71d2
--- /dev/null
+++ b/test/CodeGen/ARM/byval_load_align.ll
@@ -0,0 +1,27 @@
+; RUN: llc < %s -mtriple thumbv7-apple-ios -O1 | FileCheck %s
+
+; rdar://15144402
+; Make sure we don't assume 4-byte alignment when loading from a byval argument
+; with alignment of 2.
+; CHECK: ldr r1, [r[[REG:[0-9]+]]]
+; CHECK: ldr r2, [r[[REG]], #4]
+; CHECK: ldr r3, [r[[REG]], #8]
+; CHECK-NOT: ldm
+; CHECK: .align	1 @ @sID
+
+%struct.ModuleID = type { [32 x i8], [32 x i8], i16 }
+
+@sID = internal constant %struct.ModuleID { [32 x i8] c"TEST\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00", [32 x i8] c"1.0\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00", i16 23 }, align 2
+
+; Function Attrs: nounwind ssp
+define void @Client() #0 {
+entry:
+  tail call void @Logger(i8 signext 97, %struct.ModuleID* byval @sID) #2
+  ret void
+}
+
+declare void @Logger(i8 signext, %struct.ModuleID* byval) #1
+
+attributes #0 = { nounwind ssp "less-precise-fpmad"="false" "no-frame-pointer-elim"="true" "no-frame-pointer-elim-non-leaf" "no-infs-fp-math"="false" "no-nans-fp-math"="false" "stack-protector-buffer-size"="8" "unsafe-fp-math"="false" "use-soft-float"="false" }
+attributes #1 = { "less-precise-fpmad"="false" "no-frame-pointer-elim"="true" "no-frame-pointer-elim-non-leaf" "no-infs-fp-math"="false" "no-nans-fp-math"="false" "stack-protector-buffer-size"="8" "unsafe-fp-math"="false" "use-soft-float"="false" }
+attributes #2 = { nounwind }