Index: lib/CodeGen/SelectionDAG/LegalizeDAG.cpp
===================================================================
--- lib/CodeGen/SelectionDAG/LegalizeDAG.cpp
+++ lib/CodeGen/SelectionDAG/LegalizeDAG.cpp
@@ -1996,14 +1996,15 @@
     Type *ArgTy = ArgVT.getTypeForEVT(*DAG.getContext());
     Entry.Node = Op;
     Entry.Ty = ArgTy;
-    Entry.IsSExt = isSigned;
-    Entry.IsZExt = !isSigned;
+    Entry.IsSExt = TLI.shouldSignExtendTypeInLibCall(ArgVT, isSigned);
+    Entry.IsZExt = !TLI.shouldSignExtendTypeInLibCall(ArgVT, isSigned);
     Args.push_back(Entry);
   }
   SDValue Callee = DAG.getExternalSymbol(TLI.getLibcallName(LC),
                                          TLI.getPointerTy(DAG.getDataLayout()));
 
-  Type *RetTy = Node->getValueType(0).getTypeForEVT(*DAG.getContext());
+  EVT RetVT = Node->getValueType(0);
+  Type *RetTy = RetVT.getTypeForEVT(*DAG.getContext());
 
   // By default, the input chain to this libcall is the entry node of the
   // function. If the libcall is going to be emitted as a tail call then
@@ -2022,13 +2023,14 @@
     InChain = TCChain;
 
   TargetLowering::CallLoweringInfo CLI(DAG);
+  bool signExtend = TLI.shouldSignExtendTypeInLibCall(RetVT, isSigned);
   CLI.setDebugLoc(SDLoc(Node))
       .setChain(InChain)
       .setLibCallee(TLI.getLibcallCallingConv(LC), RetTy, Callee,
                     std::move(Args))
       .setTailCall(isTailCall)
-      .setSExtResult(isSigned)
-      .setZExtResult(!isSigned)
+      .setSExtResult(signExtend)
+      .setZExtResult(!signExtend)
       .setIsPostTypeLegalization(true);
 
   std::pair<SDValue, SDValue> CallInfo = TLI.LowerCallTo(CLI);
Index: lib/Target/Mips/MipsISelLowering.cpp
===================================================================
--- lib/Target/Mips/MipsISelLowering.cpp
+++ lib/Target/Mips/MipsISelLowering.cpp
@@ -3507,10 +3507,9 @@
 
 bool
 MipsTargetLowering::shouldSignExtendTypeInLibCall(EVT Type, bool IsSigned) const {
-  if (Subtarget.hasMips3() && Subtarget.useSoftFloat()) {
-    if (Type == MVT::i32)
+  if ((ABI.IsN32() || ABI.IsN64()) && Type == MVT::i32)
       return true;
-  }
+
   return IsSigned;
 }
 
Index: test/CodeGen/Mips/pr36061.ll
===================================================================
--- /dev/null
+++ test/CodeGen/Mips/pr36061.ll
@@ -0,0 +1,65 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
+; RUN: llc < %s -mtriple=mips64el-unknown-linux-gnu -target-abi n64 | FileCheck %s --check-prefix=MIPSN64
+; RUN: llc < %s -mtriple=mips64el-unknown-linux-gnu -target-abi n32 | FileCheck %s --check-prefix=MIPSN32
+
+; Test that powi has its integer argument sign extended on mips64.
+
+declare double @llvm.powi.f64(double, i32)
+
+define double @powi(double %value, i32 %power) {
+; MIPSN64-LABEL: powi:
+; MIPSN64:       # %bb.0:
+; MIPSN64-NEXT:    daddiu $sp, $sp, -16
+; MIPSN64-NEXT:    .cfi_def_cfa_offset 16
+; MIPSN64-NEXT:    sd $ra, 8($sp) # 8-byte Folded Spill
+; MIPSN64-NEXT:    .cfi_offset 31, -8
+; MIPSN64-NEXT:    jal __powidf2
+; MIPSN64-NEXT:    sll $5, $5, 0
+; MIPSN64-NEXT:    ld $ra, 8($sp) # 8-byte Folded Reload
+; MIPSN64-NEXT:    jr $ra
+; MIPSN64-NEXT:    daddiu $sp, $sp, 16
+;
+; MIPSN32-LABEL: powi:
+; MIPSN32:       # %bb.0:
+; MIPSN32-NEXT:    addiu $sp, $sp, -16
+; MIPSN32-NEXT:    .cfi_def_cfa_offset 16
+; MIPSN32-NEXT:    sd $ra, 8($sp) # 8-byte Folded Spill
+; MIPSN32-NEXT:    .cfi_offset 31, -8
+; MIPSN32-NEXT:    jal __powidf2
+; MIPSN32-NEXT:    sll $5, $5, 0
+; MIPSN32-NEXT:    ld $ra, 8($sp) # 8-byte Folded Reload
+; MIPSN32-NEXT:    jr $ra
+; MIPSN32-NEXT:    addiu $sp, $sp, 16
+        %1 = tail call double @llvm.powi.f64(double %value, i32 %power)
+        ret double %1
+}
+
+declare float @llvm.powi.f32(float, i32)
+
+define float @powfi(float %value, i32 %power) {
+; MIPSN64-LABEL: powfi:
+; MIPSN64:       # %bb.0:
+; MIPSN64-NEXT:    daddiu $sp, $sp, -16
+; MIPSN64-NEXT:    .cfi_def_cfa_offset 16
+; MIPSN64-NEXT:    sd $ra, 8($sp) # 8-byte Folded Spill
+; MIPSN64-NEXT:    .cfi_offset 31, -8
+; MIPSN64-NEXT:    jal __powisf2
+; MIPSN64-NEXT:    sll $5, $5, 0
+; MIPSN64-NEXT:    ld $ra, 8($sp) # 8-byte Folded Reload
+; MIPSN64-NEXT:    jr $ra
+; MIPSN64-NEXT:    daddiu $sp, $sp, 16
+;
+; MIPSN32-LABEL: powfi:
+; MIPSN32:       # %bb.0:
+; MIPSN32-NEXT:    addiu $sp, $sp, -16
+; MIPSN32-NEXT:    .cfi_def_cfa_offset 16
+; MIPSN32-NEXT:    sd $ra, 8($sp) # 8-byte Folded Spill
+; MIPSN32-NEXT:    .cfi_offset 31, -8
+; MIPSN32-NEXT:    jal __powisf2
+; MIPSN32-NEXT:    sll $5, $5, 0
+; MIPSN32-NEXT:    ld $ra, 8($sp) # 8-byte Folded Reload
+; MIPSN32-NEXT:    jr $ra
+; MIPSN32-NEXT:    addiu $sp, $sp, 16
+        %1 = tail call float @llvm.powi.f32(float %value, i32 %power)
+        ret float %1
+}