Index: clang/lib/Basic/Targets/RISCV.h
===================================================================
--- clang/lib/Basic/Targets/RISCV.h
+++ clang/lib/Basic/Targets/RISCV.h
@@ -133,7 +133,7 @@
       : RISCVTargetInfo(Triple, Opts) {
     LongWidth = LongAlign = PointerWidth = PointerAlign = 64;
     IntMaxType = Int64Type = SignedLong;
-    resetDataLayout("e-m:e-p:64:64-i64:64-i128:128-n64-S128");
+    resetDataLayout("e-m:e-p:64:64-i64:64-i128:128-n32:64-S128");
   }
 
   bool setABI(const std::string &Name) override {
Index: llvm/lib/IR/AutoUpgrade.cpp
===================================================================
--- llvm/lib/IR/AutoUpgrade.cpp
+++ llvm/lib/IR/AutoUpgrade.cpp
@@ -4598,6 +4598,13 @@
     return DL.empty() ? std::string("G1") : (DL + "-G1").str();
   }
 
+  if (T.isRISCV() && T.isArch64Bit()) {
+    auto I = DL.find("-n64-");
+    if (I != StringRef::npos)
+      return (DL.take_front(I) + "-n32:64-" + DL.drop_front(I + 5)).str();
+    return DL.str();
+  }
+
   std::string Res = DL.str();
   if (!T.isX86())
     return Res;
Index: llvm/lib/Target/RISCV/RISCVTargetMachine.cpp
===================================================================
--- llvm/lib/Target/RISCV/RISCVTargetMachine.cpp
+++ llvm/lib/Target/RISCV/RISCVTargetMachine.cpp
@@ -52,7 +52,7 @@
 
 static StringRef computeDataLayout(const Triple &TT) {
   if (TT.isArch64Bit())
-    return "e-m:e-p:64:64-i64:64-i128:128-n64-S128";
+    return "e-m:e-p:64:64-i64:64-i128:128-n32:64-S128";
   assert(TT.isArch32Bit() && "only RV32 and RV64 are currently supported");
   return "e-m:e-p:32:32-i64:64-n32-S128";
 }
Index: llvm/test/CodeGen/RISCV/aext-to-sext.ll
===================================================================
--- llvm/test/CodeGen/RISCV/aext-to-sext.ll
+++ llvm/test/CodeGen/RISCV/aext-to-sext.ll
@@ -11,24 +11,21 @@
 define void @quux(i32 signext %arg, i32 signext %arg1) nounwind {
 ; RV64I-LABEL: quux:
 ; RV64I:       # %bb.0: # %bb
-; RV64I-NEXT:    addi sp, sp, -32
-; RV64I-NEXT:    sd ra, 24(sp) # 8-byte Folded Spill
-; RV64I-NEXT:    sd s0, 16(sp) # 8-byte Folded Spill
-; RV64I-NEXT:    sd s1, 8(sp) # 8-byte Folded Spill
+; RV64I-NEXT:    addi sp, sp, -16
+; RV64I-NEXT:    sd ra, 8(sp) # 8-byte Folded Spill
+; RV64I-NEXT:    sd s0, 0(sp) # 8-byte Folded Spill
 ; RV64I-NEXT:    beq a0, a1, .LBB0_3
 ; RV64I-NEXT:  # %bb.1: # %bb2.preheader
-; RV64I-NEXT:    mv s0, a1
-; RV64I-NEXT:    mv s1, a0
+; RV64I-NEXT:    subw s0, a1, a0
 ; RV64I-NEXT:  .LBB0_2: # %bb2
 ; RV64I-NEXT:    # =>This Inner Loop Header: Depth=1
 ; RV64I-NEXT:    call hoge@plt
-; RV64I-NEXT:    addiw s1, s1, 1
-; RV64I-NEXT:    bne s1, s0, .LBB0_2
+; RV64I-NEXT:    addiw s0, s0, -1
+; RV64I-NEXT:    bnez s0, .LBB0_2
 ; RV64I-NEXT:  .LBB0_3: # %bb6
-; RV64I-NEXT:    ld ra, 24(sp) # 8-byte Folded Reload
-; RV64I-NEXT:    ld s0, 16(sp) # 8-byte Folded Reload
-; RV64I-NEXT:    ld s1, 8(sp) # 8-byte Folded Reload
-; RV64I-NEXT:    addi sp, sp, 32
+; RV64I-NEXT:    ld ra, 8(sp) # 8-byte Folded Reload
+; RV64I-NEXT:    ld s0, 0(sp) # 8-byte Folded Reload
+; RV64I-NEXT:    addi sp, sp, 16
 ; RV64I-NEXT:    ret
 bb:
   %tmp = icmp eq i32 %arg, %arg1
Index: llvm/test/CodeGen/RISCV/rvv/fixed-vector-strided-load-store.ll
===================================================================
--- llvm/test/CodeGen/RISCV/rvv/fixed-vector-strided-load-store.ll
+++ llvm/test/CodeGen/RISCV/rvv/fixed-vector-strided-load-store.ll
@@ -1070,20 +1070,21 @@
 ; CHECK-ASM-NEXT:  # %bb.4:
 ; CHECK-ASM-NEXT:    beq a4, a5, .LBB12_7
 ; CHECK-ASM-NEXT:  .LBB12_5:
-; CHECK-ASM-NEXT:    slli a2, a3, 2
-; CHECK-ASM-NEXT:    add a2, a2, a3
-; CHECK-ASM-NEXT:    add a1, a1, a2
-; CHECK-ASM-NEXT:    li a2, 1024
+; CHECK-ASM-NEXT:    addiw a2, a3, -1024
+; CHECK-ASM-NEXT:    add a0, a0, a3
+; CHECK-ASM-NEXT:    slli a4, a3, 2
+; CHECK-ASM-NEXT:    add a3, a4, a3
+; CHECK-ASM-NEXT:    add a1, a1, a3
 ; CHECK-ASM-NEXT:  .LBB12_6: # =>This Inner Loop Header: Depth=1
-; CHECK-ASM-NEXT:    lb a4, 0(a1)
-; CHECK-ASM-NEXT:    add a5, a0, a3
-; CHECK-ASM-NEXT:    lb a6, 0(a5)
-; CHECK-ASM-NEXT:    addw a4, a6, a4
-; CHECK-ASM-NEXT:    sb a4, 0(a5)
-; CHECK-ASM-NEXT:    addiw a4, a3, 1
-; CHECK-ASM-NEXT:    addi a3, a3, 1
+; CHECK-ASM-NEXT:    lb a3, 0(a1)
+; CHECK-ASM-NEXT:    lb a4, 0(a0)
+; CHECK-ASM-NEXT:    mv a5, a2
+; CHECK-ASM-NEXT:    addw a2, a4, a3
+; CHECK-ASM-NEXT:    sb a2, 0(a0)
+; CHECK-ASM-NEXT:    addiw a2, a5, 1
+; CHECK-ASM-NEXT:    addi a0, a0, 1
 ; CHECK-ASM-NEXT:    addi a1, a1, 5
-; CHECK-ASM-NEXT:    bne a4, a2, .LBB12_6
+; CHECK-ASM-NEXT:    bgeu a2, a5, .LBB12_6
 ; CHECK-ASM-NEXT:  .LBB12_7:
 ; CHECK-ASM-NEXT:    ret
   %4 = icmp eq i32 %2, 1024
Index: llvm/test/CodeGen/RISCV/rvv/fixed-vectors-fp-buildvec.ll
===================================================================
--- llvm/test/CodeGen/RISCV/rvv/fixed-vectors-fp-buildvec.ll
+++ llvm/test/CodeGen/RISCV/rvv/fixed-vectors-fp-buildvec.ll
@@ -300,14 +300,12 @@
 ; RV64-NEXT:    addi a1, a1, %lo(.LCPI12_0)
 ; RV64-NEXT:    vsetivli zero, 4, e32, m1, ta, mu
 ; RV64-NEXT:    vlse32.v v8, (a1), zero
-; RV64-NEXT:    li a1, 0
-; RV64-NEXT:    li a2, 1024
+; RV64-NEXT:    li a1, 1024
 ; RV64-NEXT:  .LBB12_1: # =>This Inner Loop Header: Depth=1
-; RV64-NEXT:    slli a3, a1, 2
-; RV64-NEXT:    add a3, a0, a3
-; RV64-NEXT:    addiw a1, a1, 4
-; RV64-NEXT:    vse32.v v8, (a3)
-; RV64-NEXT:    bne a1, a2, .LBB12_1
+; RV64-NEXT:    vse32.v v8, (a0)
+; RV64-NEXT:    addiw a1, a1, -4
+; RV64-NEXT:    addi a0, a0, 16
+; RV64-NEXT:    bnez a1, .LBB12_1
 ; RV64-NEXT:  # %bb.2:
 ; RV64-NEXT:    ret
   br label %2
Index: llvm/unittests/Bitcode/DataLayoutUpgradeTest.cpp
===================================================================
--- llvm/unittests/Bitcode/DataLayoutUpgradeTest.cpp
+++ llvm/unittests/Bitcode/DataLayoutUpgradeTest.cpp
@@ -31,6 +31,10 @@
   // Check that AMDGPU targets add -G1 if it's not present.
   EXPECT_EQ(UpgradeDataLayoutString("e-p:32:32", "r600"), "e-p:32:32-G1");
   EXPECT_EQ(UpgradeDataLayoutString("e-p:64:64", "amdgcn"), "e-p:64:64-G1");
+
+  EXPECT_EQ(UpgradeDataLayoutString("e-m:e-p:64:64-i64:64-i128:128-n64-S128",
+                                    "riscv64"),
+            "e-m:e-p:64:64-i64:64-i128:128-n32:64-S128");
 }
 
 TEST(DataLayoutUpgradeTest, NoDataLayoutUpgrade) {