diff --git a/llvm/include/llvm/Target/TargetLowering.h b/llvm/include/llvm/Target/TargetLowering.h
index 5a05c8c37bf2..fda362d8ceb5 100644
--- a/llvm/include/llvm/Target/TargetLowering.h
+++ b/llvm/include/llvm/Target/TargetLowering.h
@@ -22,6 +22,7 @@
 #ifndef LLVM_TARGET_TARGETLOWERING_H
 #define LLVM_TARGET_TARGETLOWERING_H
 
+#include "llvm/CallingConv.h"
 #include "llvm/InlineAsm.h"
 #include "llvm/CodeGen/SelectionDAGNodes.h"
 #include "llvm/CodeGen/RuntimeLibcalls.h"
@@ -1539,6 +1540,18 @@ public:
     return CmpLibcallCCs[Call];
   }
 
+  /// setLibcallCallingConv - Set the CallingConv that should be used for the
+  /// specified libcall.
+  void setLibcallCallingConv(RTLIB::Libcall Call, CallingConv::ID CC) {
+    LibcallCallingConvs[Call] = CC;
+  }
+  
+  /// getLibcallCallingConv - Get the CallingConv that should be used for the
+  /// specified libcall.
+  CallingConv::ID getLibcallCallingConv(RTLIB::Libcall Call) const {
+    return LibcallCallingConvs[Call];
+  }
+
 private:
   TargetMachine &TM;
   const TargetData *TD;
@@ -1705,6 +1718,10 @@ private:
   /// of each of the comparison libcall against zero.
   ISD::CondCode CmpLibcallCCs[RTLIB::UNKNOWN_LIBCALL];
 
+  /// LibcallCallingConvs - Stores the CallingConv that should be used for each
+  /// libcall.
+  CallingConv::ID LibcallCallingConvs[RTLIB::UNKNOWN_LIBCALL];
+
 protected:
   /// When lowering \@llvm.memset this field specifies the maximum number of
   /// store operations that may be substituted for the call to memset. Targets
diff --git a/llvm/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp b/llvm/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp
index ab4ebefa30bf..66469ef3c930 100644
--- a/llvm/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp
@@ -1869,7 +1869,7 @@ SDValue SelectionDAGLegalize::ExpandLibCall(RTLIB::Libcall LC, SDNode *Node,
   const Type *RetTy = Node->getValueType(0).getTypeForEVT(*DAG.getContext());
   std::pair<SDValue, SDValue> CallInfo =
     TLI.LowerCallTo(InChain, RetTy, isSigned, !isSigned, false, false,
-                    0, CallingConv::C, false,
+                    0, TLI.getLibcallCallingConv(LC), false,
                     /*isReturnValueUsed=*/true,
                     Callee, Args, DAG,
                     Node->getDebugLoc());
diff --git a/llvm/lib/CodeGen/SelectionDAG/LegalizeTypes.cpp b/llvm/lib/CodeGen/SelectionDAG/LegalizeTypes.cpp
index 11ec9f168c06..1518317328fa 100644
--- a/llvm/lib/CodeGen/SelectionDAG/LegalizeTypes.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/LegalizeTypes.cpp
@@ -1019,7 +1019,7 @@ SDValue DAGTypeLegalizer::MakeLibCall(RTLIB::Libcall LC, EVT RetVT,
   const Type *RetTy = RetVT.getTypeForEVT(*DAG.getContext());
   std::pair<SDValue,SDValue> CallInfo =
     TLI.LowerCallTo(DAG.getEntryNode(), RetTy, isSigned, !isSigned, false,
-                    false, 0, CallingConv::C, false,
+                    false, 0, TLI.getLibcallCallingConv(LC), false,
                     /*isReturnValueUsed=*/true,
                     Callee, Args, DAG, dl);
   return CallInfo.first;
diff --git a/llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp b/llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
index afcbc0987bf8..5d4717ac593c 100644
--- a/llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
@@ -3390,7 +3390,8 @@ SDValue SelectionDAG::getMemcpy(SDValue Chain, DebugLoc dl, SDValue Dst,
   // FIXME: pass in DebugLoc
   std::pair<SDValue,SDValue> CallResult =
     TLI.LowerCallTo(Chain, Type::getVoidTy(*getContext()),
-                    false, false, false, false, 0, CallingConv::C, false,
+                    false, false, false, false, 0,
+                    TLI.getLibcallCallingConv(RTLIB::MEMCPY), false,
                     /*isReturnValueUsed=*/false,
                     getExternalSymbol(TLI.getLibcallName(RTLIB::MEMCPY), 
                                       TLI.getPointerTy()),
@@ -3438,7 +3439,8 @@ SDValue SelectionDAG::getMemmove(SDValue Chain, DebugLoc dl, SDValue Dst,
   // FIXME:  pass in DebugLoc
   std::pair<SDValue,SDValue> CallResult =
     TLI.LowerCallTo(Chain, Type::getVoidTy(*getContext()),
-                    false, false, false, false, 0, CallingConv::C, false,
+                    false, false, false, false, 0,
+                    TLI.getLibcallCallingConv(RTLIB::MEMMOVE), false,
                     /*isReturnValueUsed=*/false,
                     getExternalSymbol(TLI.getLibcallName(RTLIB::MEMMOVE), 
                                       TLI.getPointerTy()),
@@ -3496,7 +3498,8 @@ SDValue SelectionDAG::getMemset(SDValue Chain, DebugLoc dl, SDValue Dst,
   // FIXME: pass in DebugLoc
   std::pair<SDValue,SDValue> CallResult =
     TLI.LowerCallTo(Chain, Type::getVoidTy(*getContext()),
-                    false, false, false, false, 0, CallingConv::C, false,
+                    false, false, false, false, 0,
+                    TLI.getLibcallCallingConv(RTLIB::MEMSET), false,
                     /*isReturnValueUsed=*/false,
                     getExternalSymbol(TLI.getLibcallName(RTLIB::MEMSET), 
                                       TLI.getPointerTy()),
diff --git a/llvm/lib/CodeGen/SelectionDAG/TargetLowering.cpp b/llvm/lib/CodeGen/SelectionDAG/TargetLowering.cpp
index 767238e78136..3414fee7d4da 100644
--- a/llvm/lib/CodeGen/SelectionDAG/TargetLowering.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/TargetLowering.cpp
@@ -247,6 +247,14 @@ static void InitLibcallNames(const char **Names) {
   Names[RTLIB::UNWIND_RESUME] = "_Unwind_Resume";
 }
 
+/// InitLibcallCallingConvs - Set default libcall CallingConvs.
+///
+static void InitLibcallCallingConvs(CallingConv::ID *CCs) {
+  for (int i = 0; i < RTLIB::UNKNOWN_LIBCALL; ++i) {
+    CCs[i] = CallingConv::C;
+  }
+}
+
 /// getFPEXT - Return the FPEXT_*_* value for the given types, or
 /// UNKNOWN_LIBCALL if there is none.
 RTLIB::Libcall RTLIB::getFPEXT(EVT OpVT, EVT RetVT) {
@@ -520,6 +528,7 @@ TargetLowering::TargetLowering(TargetMachine &tm,TargetLoweringObjectFile *tlof)
 
   InitLibcallNames(LibcallRoutineNames);
   InitCmpLibcallCCs(CmpLibcallCCs);
+  InitLibcallCallingConvs(LibcallCallingConvs);
 
   // Tell Legalize whether the assembler supports DEBUG_LOC.
   const TargetAsmInfo *TASM = TM.getTargetAsmInfo();
diff --git a/llvm/lib/Target/ARM/ARMISelLowering.cpp b/llvm/lib/Target/ARM/ARMISelLowering.cpp
index 9138c5730c45..a4471000b0c9 100644
--- a/llvm/lib/Target/ARM/ARMISelLowering.cpp
+++ b/llvm/lib/Target/ARM/ARMISelLowering.cpp
@@ -201,6 +201,15 @@ ARMTargetLowering::ARMTargetLowering(TargetMachine &TM)
   setLibcallName(RTLIB::SRL_I128, 0);
   setLibcallName(RTLIB::SRA_I128, 0);
 
+  // Libcalls should use the AAPCS base standard ABI, even if hard float
+  // is in effect, as per the ARM RTABI specification, section 4.1.2.
+  if (Subtarget->isAAPCS_ABI()) {
+    for (int i = 0; i < RTLIB::UNKNOWN_LIBCALL; ++i) {
+      setLibcallCallingConv(static_cast<RTLIB::Libcall>(i),
+                            CallingConv::ARM_AAPCS);
+    }
+  }
+
   if (Subtarget->isThumb1Only())
     addRegisterClass(MVT::i32, ARM::tGPRRegisterClass);
   else
diff --git a/llvm/lib/Target/CellSPU/SPUISelLowering.cpp b/llvm/lib/Target/CellSPU/SPUISelLowering.cpp
index be3030d55642..84dbb6a9a0f1 100644
--- a/llvm/lib/Target/CellSPU/SPUISelLowering.cpp
+++ b/llvm/lib/Target/CellSPU/SPUISelLowering.cpp
@@ -116,7 +116,7 @@ namespace {
                 Op.getNode()->getValueType(0).getTypeForEVT(*DAG.getContext());
     std::pair<SDValue, SDValue> CallInfo =
             TLI.LowerCallTo(InChain, RetTy, isSigned, !isSigned, false, false,
-                            0, CallingConv::C, false,
+                            0, TLI.getLibcallCallingConv(LC), false,
                             /*isReturnValueUsed=*/true,
                             Callee, Args, DAG,
                             Op.getDebugLoc());