Index: llvm/lib/Target/RISCV/RISCVISelLowering.cpp
===================================================================
--- llvm/lib/Target/RISCV/RISCVISelLowering.cpp
+++ llvm/lib/Target/RISCV/RISCVISelLowering.cpp
@@ -3814,16 +3814,24 @@
                                                  SDValue C) const {
   // Check integral scalar types.
   if (VT.isScalarInteger()) {
-    // Do not perform the transformation on riscv32 with the M extension.
-    if (!Subtarget.is64Bit() && Subtarget.hasStdExtM())
+    // Do not perform the transformation on riscv32 with the M extension or
+    // if the data type exceeds 64-bit.
+    if ((Subtarget.hasStdExtM() || VT.getSizeInBits() > 64) &&
+        !Subtarget.is64Bit())
       return false;
     if (auto *ConstNode = dyn_cast<ConstantSDNode>(C.getNode())) {
-      if (ConstNode->getAPIntValue().getBitWidth() > 8 * sizeof(int64_t))
-        return false;
-      int64_t Imm = ConstNode->getSExtValue();
-      if (isPowerOf2_64(Imm + 1) || isPowerOf2_64(Imm - 1) ||
-          isPowerOf2_64(1 - Imm) || isPowerOf2_64(-1 - Imm))
+      const APInt &Imm = ConstNode->getAPIntValue();
+      // Optimize to ±(1<<m)±1 if applicable.
+      if ((Imm + 1).isPowerOf2() || (Imm - 1).isPowerOf2() ||
+          (1 - Imm).isPowerOf2() || (-1 - Imm).isPowerOf2())
+        return true;
+      // Optimize to (1<<m)±(1<<n) if Imm needs a pair of LUI/ADDI.
+      if (!Imm.isSignedIntN(12) && Imm.countTrailingZeros() < 12) {
+        APInt ImmS = Imm.ashr(Imm.countTrailingZeros());
+        if ((ImmS + 1).isPowerOf2() || (ImmS - 1).isPowerOf2() ||
+            (1 - ImmS).isPowerOf2())
         return true;
+      }
     }
   }
 
Index: llvm/test/CodeGen/RISCV/mul.ll
===================================================================
--- llvm/test/CodeGen/RISCV/mul.ll
+++ llvm/test/CodeGen/RISCV/mul.ll
@@ -638,13 +638,9 @@
 define i32 @muli32_p4352(i32 %a) nounwind {
 ; RV32I-LABEL: muli32_p4352:
 ; RV32I:       # %bb.0:
-; RV32I-NEXT:    addi sp, sp, -16
-; RV32I-NEXT:    sw ra, 12(sp) # 4-byte Folded Spill
-; RV32I-NEXT:    lui a1, 1
-; RV32I-NEXT:    addi a1, a1, 256
-; RV32I-NEXT:    call __mulsi3@plt
-; RV32I-NEXT:    lw ra, 12(sp) # 4-byte Folded Reload
-; RV32I-NEXT:    addi sp, sp, 16
+; RV32I-NEXT:    slli a1, a0, 8
+; RV32I-NEXT:    slli a0, a0, 12
+; RV32I-NEXT:    add a0, a0, a1
 ; RV32I-NEXT:    ret
 ;
 ; RV32IM-LABEL: muli32_p4352:
@@ -656,20 +652,16 @@
 ;
 ; RV64I-LABEL: muli32_p4352:
 ; RV64I:       # %bb.0:
-; RV64I-NEXT:    addi sp, sp, -16
-; RV64I-NEXT:    sd ra, 8(sp) # 8-byte Folded Spill
-; RV64I-NEXT:    lui a1, 1
-; RV64I-NEXT:    addiw a1, a1, 256
-; RV64I-NEXT:    call __muldi3@plt
-; RV64I-NEXT:    ld ra, 8(sp) # 8-byte Folded Reload
-; RV64I-NEXT:    addi sp, sp, 16
+; RV64I-NEXT:    slli a1, a0, 8
+; RV64I-NEXT:    slli a0, a0, 12
+; RV64I-NEXT:    addw a0, a0, a1
 ; RV64I-NEXT:    ret
 ;
 ; RV64IM-LABEL: muli32_p4352:
 ; RV64IM:       # %bb.0:
-; RV64IM-NEXT:    lui a1, 1
-; RV64IM-NEXT:    addiw a1, a1, 256
-; RV64IM-NEXT:    mul a0, a0, a1
+; RV64IM-NEXT:    slli a1, a0, 8
+; RV64IM-NEXT:    slli a0, a0, 12
+; RV64IM-NEXT:    addw a0, a0, a1
 ; RV64IM-NEXT:    ret
   %1 = mul i32 %a, 4352
   ret i32 %1
@@ -678,13 +670,9 @@
 define i32 @muli32_p3840(i32 %a) nounwind {
 ; RV32I-LABEL: muli32_p3840:
 ; RV32I:       # %bb.0:
-; RV32I-NEXT:    addi sp, sp, -16
-; RV32I-NEXT:    sw ra, 12(sp) # 4-byte Folded Spill
-; RV32I-NEXT:    lui a1, 1
-; RV32I-NEXT:    addi a1, a1, -256
-; RV32I-NEXT:    call __mulsi3@plt
-; RV32I-NEXT:    lw ra, 12(sp) # 4-byte Folded Reload
-; RV32I-NEXT:    addi sp, sp, 16
+; RV32I-NEXT:    slli a1, a0, 8
+; RV32I-NEXT:    slli a0, a0, 12
+; RV32I-NEXT:    sub a0, a0, a1
 ; RV32I-NEXT:    ret
 ;
 ; RV32IM-LABEL: muli32_p3840:
@@ -696,20 +684,16 @@
 ;
 ; RV64I-LABEL: muli32_p3840:
 ; RV64I:       # %bb.0:
-; RV64I-NEXT:    addi sp, sp, -16
-; RV64I-NEXT:    sd ra, 8(sp) # 8-byte Folded Spill
-; RV64I-NEXT:    lui a1, 1
-; RV64I-NEXT:    addiw a1, a1, -256
-; RV64I-NEXT:    call __muldi3@plt
-; RV64I-NEXT:    ld ra, 8(sp) # 8-byte Folded Reload
-; RV64I-NEXT:    addi sp, sp, 16
+; RV64I-NEXT:    slli a1, a0, 8
+; RV64I-NEXT:    slli a0, a0, 12
+; RV64I-NEXT:    subw a0, a0, a1
 ; RV64I-NEXT:    ret
 ;
 ; RV64IM-LABEL: muli32_p3840:
 ; RV64IM:       # %bb.0:
-; RV64IM-NEXT:    lui a1, 1
-; RV64IM-NEXT:    addiw a1, a1, -256
-; RV64IM-NEXT:    mul a0, a0, a1
+; RV64IM-NEXT:    slli a1, a0, 8
+; RV64IM-NEXT:    slli a0, a0, 12
+; RV64IM-NEXT:    subw a0, a0, a1
 ; RV64IM-NEXT:    ret
   %1 = mul i32 %a, 3840
   ret i32 %1
@@ -718,13 +702,9 @@
 define i32 @muli32_m3840(i32 %a) nounwind {
 ; RV32I-LABEL: muli32_m3840:
 ; RV32I:       # %bb.0:
-; RV32I-NEXT:    addi sp, sp, -16
-; RV32I-NEXT:    sw ra, 12(sp) # 4-byte Folded Spill
-; RV32I-NEXT:    lui a1, 1048575
-; RV32I-NEXT:    addi a1, a1, 256
-; RV32I-NEXT:    call __mulsi3@plt
-; RV32I-NEXT:    lw ra, 12(sp) # 4-byte Folded Reload
-; RV32I-NEXT:    addi sp, sp, 16
+; RV32I-NEXT:    slli a1, a0, 12
+; RV32I-NEXT:    slli a0, a0, 8
+; RV32I-NEXT:    sub a0, a0, a1
 ; RV32I-NEXT:    ret
 ;
 ; RV32IM-LABEL: muli32_m3840:
@@ -736,20 +716,16 @@
 ;
 ; RV64I-LABEL: muli32_m3840:
 ; RV64I:       # %bb.0:
-; RV64I-NEXT:    addi sp, sp, -16
-; RV64I-NEXT:    sd ra, 8(sp) # 8-byte Folded Spill
-; RV64I-NEXT:    lui a1, 1048575
-; RV64I-NEXT:    addiw a1, a1, 256
-; RV64I-NEXT:    call __muldi3@plt
-; RV64I-NEXT:    ld ra, 8(sp) # 8-byte Folded Reload
-; RV64I-NEXT:    addi sp, sp, 16
+; RV64I-NEXT:    slli a1, a0, 12
+; RV64I-NEXT:    slli a0, a0, 8
+; RV64I-NEXT:    subw a0, a0, a1
 ; RV64I-NEXT:    ret
 ;
 ; RV64IM-LABEL: muli32_m3840:
 ; RV64IM:       # %bb.0:
-; RV64IM-NEXT:    lui a1, 1048575
-; RV64IM-NEXT:    addiw a1, a1, 256
-; RV64IM-NEXT:    mul a0, a0, a1
+; RV64IM-NEXT:    slli a1, a0, 12
+; RV64IM-NEXT:    slli a0, a0, 8
+; RV64IM-NEXT:    subw a0, a0, a1
 ; RV64IM-NEXT:    ret
   %1 = mul i32 %a, -3840
   ret i32 %1
@@ -798,14 +774,18 @@
 define i64 @muli64_p4352(i64 %a) nounwind {
 ; RV32I-LABEL: muli64_p4352:
 ; RV32I:       # %bb.0:
-; RV32I-NEXT:    addi sp, sp, -16
-; RV32I-NEXT:    sw ra, 12(sp) # 4-byte Folded Spill
-; RV32I-NEXT:    lui a2, 1
-; RV32I-NEXT:    addi a2, a2, 256
-; RV32I-NEXT:    mv a3, zero
-; RV32I-NEXT:    call __muldi3@plt
-; RV32I-NEXT:    lw ra, 12(sp) # 4-byte Folded Reload
-; RV32I-NEXT:    addi sp, sp, 16
+; RV32I-NEXT:    srli a2, a0, 24
+; RV32I-NEXT:    slli a3, a1, 8
+; RV32I-NEXT:    or a2, a3, a2
+; RV32I-NEXT:    srli a3, a0, 20
+; RV32I-NEXT:    slli a1, a1, 12
+; RV32I-NEXT:    or a1, a1, a3
+; RV32I-NEXT:    add a1, a1, a2
+; RV32I-NEXT:    slli a2, a0, 8
+; RV32I-NEXT:    slli a3, a0, 12
+; RV32I-NEXT:    add a0, a3, a2
+; RV32I-NEXT:    sltu a2, a0, a3
+; RV32I-NEXT:    add a1, a1, a2
 ; RV32I-NEXT:    ret
 ;
 ; RV32IM-LABEL: muli64_p4352:
@@ -820,20 +800,16 @@
 ;
 ; RV64I-LABEL: muli64_p4352:
 ; RV64I:       # %bb.0:
-; RV64I-NEXT:    addi sp, sp, -16
-; RV64I-NEXT:    sd ra, 8(sp) # 8-byte Folded Spill
-; RV64I-NEXT:    lui a1, 1
-; RV64I-NEXT:    addiw a1, a1, 256
-; RV64I-NEXT:    call __muldi3@plt
-; RV64I-NEXT:    ld ra, 8(sp) # 8-byte Folded Reload
-; RV64I-NEXT:    addi sp, sp, 16
+; RV64I-NEXT:    slli a1, a0, 8
+; RV64I-NEXT:    slli a0, a0, 12
+; RV64I-NEXT:    add a0, a0, a1
 ; RV64I-NEXT:    ret
 ;
 ; RV64IM-LABEL: muli64_p4352:
 ; RV64IM:       # %bb.0:
-; RV64IM-NEXT:    lui a1, 1
-; RV64IM-NEXT:    addiw a1, a1, 256
-; RV64IM-NEXT:    mul a0, a0, a1
+; RV64IM-NEXT:    slli a1, a0, 8
+; RV64IM-NEXT:    slli a0, a0, 12
+; RV64IM-NEXT:    add a0, a0, a1
 ; RV64IM-NEXT:    ret
   %1 = mul i64 %a, 4352
   ret i64 %1
@@ -842,14 +818,18 @@
 define i64 @muli64_p3840(i64 %a) nounwind {
 ; RV32I-LABEL: muli64_p3840:
 ; RV32I:       # %bb.0:
-; RV32I-NEXT:    addi sp, sp, -16
-; RV32I-NEXT:    sw ra, 12(sp) # 4-byte Folded Spill
-; RV32I-NEXT:    lui a2, 1
-; RV32I-NEXT:    addi a2, a2, -256
-; RV32I-NEXT:    mv a3, zero
-; RV32I-NEXT:    call __muldi3@plt
-; RV32I-NEXT:    lw ra, 12(sp) # 4-byte Folded Reload
-; RV32I-NEXT:    addi sp, sp, 16
+; RV32I-NEXT:    srli a2, a0, 24
+; RV32I-NEXT:    slli a3, a1, 8
+; RV32I-NEXT:    or a2, a3, a2
+; RV32I-NEXT:    srli a3, a0, 20
+; RV32I-NEXT:    slli a1, a1, 12
+; RV32I-NEXT:    or a1, a1, a3
+; RV32I-NEXT:    sub a1, a1, a2
+; RV32I-NEXT:    slli a2, a0, 8
+; RV32I-NEXT:    slli a0, a0, 12
+; RV32I-NEXT:    sltu a3, a0, a2
+; RV32I-NEXT:    sub a1, a1, a3
+; RV32I-NEXT:    sub a0, a0, a2
 ; RV32I-NEXT:    ret
 ;
 ; RV32IM-LABEL: muli64_p3840:
@@ -864,20 +844,16 @@
 ;
 ; RV64I-LABEL: muli64_p3840:
 ; RV64I:       # %bb.0:
-; RV64I-NEXT:    addi sp, sp, -16
-; RV64I-NEXT:    sd ra, 8(sp) # 8-byte Folded Spill
-; RV64I-NEXT:    lui a1, 1
-; RV64I-NEXT:    addiw a1, a1, -256
-; RV64I-NEXT:    call __muldi3@plt
-; RV64I-NEXT:    ld ra, 8(sp) # 8-byte Folded Reload
-; RV64I-NEXT:    addi sp, sp, 16
+; RV64I-NEXT:    slli a1, a0, 8
+; RV64I-NEXT:    slli a0, a0, 12
+; RV64I-NEXT:    sub a0, a0, a1
 ; RV64I-NEXT:    ret
 ;
 ; RV64IM-LABEL: muli64_p3840:
 ; RV64IM:       # %bb.0:
-; RV64IM-NEXT:    lui a1, 1
-; RV64IM-NEXT:    addiw a1, a1, -256
-; RV64IM-NEXT:    mul a0, a0, a1
+; RV64IM-NEXT:    slli a1, a0, 8
+; RV64IM-NEXT:    slli a0, a0, 12
+; RV64IM-NEXT:    sub a0, a0, a1
 ; RV64IM-NEXT:    ret
   %1 = mul i64 %a, 3840
   ret i64 %1
@@ -931,14 +907,18 @@
 define i64 @muli64_m3840(i64 %a) nounwind {
 ; RV32I-LABEL: muli64_m3840:
 ; RV32I:       # %bb.0:
-; RV32I-NEXT:    addi sp, sp, -16
-; RV32I-NEXT:    sw ra, 12(sp) # 4-byte Folded Spill
-; RV32I-NEXT:    lui a2, 1048575
-; RV32I-NEXT:    addi a2, a2, 256
-; RV32I-NEXT:    addi a3, zero, -1
-; RV32I-NEXT:    call __muldi3@plt
-; RV32I-NEXT:    lw ra, 12(sp) # 4-byte Folded Reload
-; RV32I-NEXT:    addi sp, sp, 16
+; RV32I-NEXT:    srli a2, a0, 20
+; RV32I-NEXT:    slli a3, a1, 12
+; RV32I-NEXT:    or a2, a3, a2
+; RV32I-NEXT:    srli a3, a0, 24
+; RV32I-NEXT:    slli a1, a1, 8
+; RV32I-NEXT:    or a1, a1, a3
+; RV32I-NEXT:    sub a1, a1, a2
+; RV32I-NEXT:    slli a2, a0, 12
+; RV32I-NEXT:    slli a0, a0, 8
+; RV32I-NEXT:    sltu a3, a0, a2
+; RV32I-NEXT:    sub a1, a1, a3
+; RV32I-NEXT:    sub a0, a0, a2
 ; RV32I-NEXT:    ret
 ;
 ; RV32IM-LABEL: muli64_m3840:
@@ -954,21 +934,231 @@
 ;
 ; RV64I-LABEL: muli64_m3840:
 ; RV64I:       # %bb.0:
-; RV64I-NEXT:    addi sp, sp, -16
-; RV64I-NEXT:    sd ra, 8(sp) # 8-byte Folded Spill
-; RV64I-NEXT:    lui a1, 1048575
-; RV64I-NEXT:    addiw a1, a1, 256
-; RV64I-NEXT:    call __muldi3@plt
-; RV64I-NEXT:    ld ra, 8(sp) # 8-byte Folded Reload
-; RV64I-NEXT:    addi sp, sp, 16
+; RV64I-NEXT:    slli a1, a0, 12
+; RV64I-NEXT:    slli a0, a0, 8
+; RV64I-NEXT:    sub a0, a0, a1
 ; RV64I-NEXT:    ret
 ;
 ; RV64IM-LABEL: muli64_m3840:
 ; RV64IM:       # %bb.0:
-; RV64IM-NEXT:    lui a1, 1048575
-; RV64IM-NEXT:    addiw a1, a1, 256
-; RV64IM-NEXT:    mul a0, a0, a1
+; RV64IM-NEXT:    slli a1, a0, 12
+; RV64IM-NEXT:    slli a0, a0, 8
+; RV64IM-NEXT:    sub a0, a0, a1
 ; RV64IM-NEXT:    ret
   %1 = mul i64 %a, -3840
   ret i64 %1
 }
+
+define i128 @muli128_m3840(i128 %a) nounwind {
+; RV32I-LABEL: muli128_m3840:
+; RV32I:       # %bb.0:
+; RV32I-NEXT:    addi sp, sp, -64
+; RV32I-NEXT:    sw ra, 60(sp) # 4-byte Folded Spill
+; RV32I-NEXT:    sw s0, 56(sp) # 4-byte Folded Spill
+; RV32I-NEXT:    lw a3, 0(a1)
+; RV32I-NEXT:    lw a2, 4(a1)
+; RV32I-NEXT:    lw a4, 8(a1)
+; RV32I-NEXT:    lw a1, 12(a1)
+; RV32I-NEXT:    mv s0, a0
+; RV32I-NEXT:    addi a0, zero, -1
+; RV32I-NEXT:    sw a0, 20(sp)
+; RV32I-NEXT:    sw a0, 16(sp)
+; RV32I-NEXT:    sw a0, 12(sp)
+; RV32I-NEXT:    lui a0, 1048575
+; RV32I-NEXT:    addi a0, a0, 256
+; RV32I-NEXT:    sw a0, 8(sp)
+; RV32I-NEXT:    sw a1, 36(sp)
+; RV32I-NEXT:    sw a4, 32(sp)
+; RV32I-NEXT:    sw a2, 28(sp)
+; RV32I-NEXT:    addi a0, sp, 40
+; RV32I-NEXT:    addi a1, sp, 24
+; RV32I-NEXT:    addi a2, sp, 8
+; RV32I-NEXT:    sw a3, 24(sp)
+; RV32I-NEXT:    call __multi3@plt
+; RV32I-NEXT:    lw a0, 52(sp)
+; RV32I-NEXT:    lw a1, 48(sp)
+; RV32I-NEXT:    lw a2, 44(sp)
+; RV32I-NEXT:    lw a3, 40(sp)
+; RV32I-NEXT:    sw a0, 12(s0)
+; RV32I-NEXT:    sw a1, 8(s0)
+; RV32I-NEXT:    sw a2, 4(s0)
+; RV32I-NEXT:    sw a3, 0(s0)
+; RV32I-NEXT:    lw s0, 56(sp) # 4-byte Folded Reload
+; RV32I-NEXT:    lw ra, 60(sp) # 4-byte Folded Reload
+; RV32I-NEXT:    addi sp, sp, 64
+; RV32I-NEXT:    ret
+;
+; RV32IM-LABEL: muli128_m3840:
+; RV32IM:       # %bb.0:
+; RV32IM-NEXT:    addi sp, sp, -64
+; RV32IM-NEXT:    sw ra, 60(sp) # 4-byte Folded Spill
+; RV32IM-NEXT:    sw s0, 56(sp) # 4-byte Folded Spill
+; RV32IM-NEXT:    lw a3, 0(a1)
+; RV32IM-NEXT:    lw a2, 4(a1)
+; RV32IM-NEXT:    lw a4, 8(a1)
+; RV32IM-NEXT:    lw a1, 12(a1)
+; RV32IM-NEXT:    mv s0, a0
+; RV32IM-NEXT:    addi a0, zero, -1
+; RV32IM-NEXT:    sw a0, 20(sp)
+; RV32IM-NEXT:    sw a0, 16(sp)
+; RV32IM-NEXT:    sw a0, 12(sp)
+; RV32IM-NEXT:    lui a0, 1048575
+; RV32IM-NEXT:    addi a0, a0, 256
+; RV32IM-NEXT:    sw a0, 8(sp)
+; RV32IM-NEXT:    sw a1, 36(sp)
+; RV32IM-NEXT:    sw a4, 32(sp)
+; RV32IM-NEXT:    sw a2, 28(sp)
+; RV32IM-NEXT:    addi a0, sp, 40
+; RV32IM-NEXT:    addi a1, sp, 24
+; RV32IM-NEXT:    addi a2, sp, 8
+; RV32IM-NEXT:    sw a3, 24(sp)
+; RV32IM-NEXT:    call __multi3@plt
+; RV32IM-NEXT:    lw a0, 52(sp)
+; RV32IM-NEXT:    lw a1, 48(sp)
+; RV32IM-NEXT:    lw a2, 44(sp)
+; RV32IM-NEXT:    lw a3, 40(sp)
+; RV32IM-NEXT:    sw a0, 12(s0)
+; RV32IM-NEXT:    sw a1, 8(s0)
+; RV32IM-NEXT:    sw a2, 4(s0)
+; RV32IM-NEXT:    sw a3, 0(s0)
+; RV32IM-NEXT:    lw s0, 56(sp) # 4-byte Folded Reload
+; RV32IM-NEXT:    lw ra, 60(sp) # 4-byte Folded Reload
+; RV32IM-NEXT:    addi sp, sp, 64
+; RV32IM-NEXT:    ret
+;
+; RV64I-LABEL: muli128_m3840:
+; RV64I:       # %bb.0:
+; RV64I-NEXT:    srli a2, a0, 52
+; RV64I-NEXT:    slli a3, a1, 12
+; RV64I-NEXT:    or a2, a3, a2
+; RV64I-NEXT:    srli a3, a0, 56
+; RV64I-NEXT:    slli a1, a1, 8
+; RV64I-NEXT:    or a1, a1, a3
+; RV64I-NEXT:    sub a1, a1, a2
+; RV64I-NEXT:    slli a2, a0, 12
+; RV64I-NEXT:    slli a0, a0, 8
+; RV64I-NEXT:    sltu a3, a0, a2
+; RV64I-NEXT:    sub a1, a1, a3
+; RV64I-NEXT:    sub a0, a0, a2
+; RV64I-NEXT:    ret
+;
+; RV64IM-LABEL: muli128_m3840:
+; RV64IM:       # %bb.0:
+; RV64IM-NEXT:    srli a2, a0, 52
+; RV64IM-NEXT:    slli a3, a1, 12
+; RV64IM-NEXT:    or a2, a3, a2
+; RV64IM-NEXT:    srli a3, a0, 56
+; RV64IM-NEXT:    slli a1, a1, 8
+; RV64IM-NEXT:    or a1, a1, a3
+; RV64IM-NEXT:    sub a1, a1, a2
+; RV64IM-NEXT:    slli a2, a0, 12
+; RV64IM-NEXT:    slli a0, a0, 8
+; RV64IM-NEXT:    sltu a3, a0, a2
+; RV64IM-NEXT:    sub a1, a1, a3
+; RV64IM-NEXT:    sub a0, a0, a2
+; RV64IM-NEXT:    ret
+  %1 = mul i128 %a, -3840
+  ret i128 %1
+}
+
+define i128 @muli128_m63(i128 %a) nounwind {
+; RV32I-LABEL: muli128_m63:
+; RV32I:       # %bb.0:
+; RV32I-NEXT:    addi sp, sp, -64
+; RV32I-NEXT:    sw ra, 60(sp) # 4-byte Folded Spill
+; RV32I-NEXT:    sw s0, 56(sp) # 4-byte Folded Spill
+; RV32I-NEXT:    lw a3, 0(a1)
+; RV32I-NEXT:    lw a2, 4(a1)
+; RV32I-NEXT:    lw a4, 8(a1)
+; RV32I-NEXT:    lw a1, 12(a1)
+; RV32I-NEXT:    mv s0, a0
+; RV32I-NEXT:    addi a0, zero, -1
+; RV32I-NEXT:    sw a0, 20(sp)
+; RV32I-NEXT:    sw a0, 16(sp)
+; RV32I-NEXT:    sw a0, 12(sp)
+; RV32I-NEXT:    addi a0, zero, -63
+; RV32I-NEXT:    sw a0, 8(sp)
+; RV32I-NEXT:    sw a1, 36(sp)
+; RV32I-NEXT:    sw a4, 32(sp)
+; RV32I-NEXT:    sw a2, 28(sp)
+; RV32I-NEXT:    addi a0, sp, 40
+; RV32I-NEXT:    addi a1, sp, 24
+; RV32I-NEXT:    addi a2, sp, 8
+; RV32I-NEXT:    sw a3, 24(sp)
+; RV32I-NEXT:    call __multi3@plt
+; RV32I-NEXT:    lw a0, 52(sp)
+; RV32I-NEXT:    lw a1, 48(sp)
+; RV32I-NEXT:    lw a2, 44(sp)
+; RV32I-NEXT:    lw a3, 40(sp)
+; RV32I-NEXT:    sw a0, 12(s0)
+; RV32I-NEXT:    sw a1, 8(s0)
+; RV32I-NEXT:    sw a2, 4(s0)
+; RV32I-NEXT:    sw a3, 0(s0)
+; RV32I-NEXT:    lw s0, 56(sp) # 4-byte Folded Reload
+; RV32I-NEXT:    lw ra, 60(sp) # 4-byte Folded Reload
+; RV32I-NEXT:    addi sp, sp, 64
+; RV32I-NEXT:    ret
+;
+; RV32IM-LABEL: muli128_m63:
+; RV32IM:       # %bb.0:
+; RV32IM-NEXT:    addi sp, sp, -64
+; RV32IM-NEXT:    sw ra, 60(sp) # 4-byte Folded Spill
+; RV32IM-NEXT:    sw s0, 56(sp) # 4-byte Folded Spill
+; RV32IM-NEXT:    lw a3, 0(a1)
+; RV32IM-NEXT:    lw a2, 4(a1)
+; RV32IM-NEXT:    lw a4, 8(a1)
+; RV32IM-NEXT:    lw a1, 12(a1)
+; RV32IM-NEXT:    mv s0, a0
+; RV32IM-NEXT:    addi a0, zero, -1
+; RV32IM-NEXT:    sw a0, 20(sp)
+; RV32IM-NEXT:    sw a0, 16(sp)
+; RV32IM-NEXT:    sw a0, 12(sp)
+; RV32IM-NEXT:    addi a0, zero, -63
+; RV32IM-NEXT:    sw a0, 8(sp)
+; RV32IM-NEXT:    sw a1, 36(sp)
+; RV32IM-NEXT:    sw a4, 32(sp)
+; RV32IM-NEXT:    sw a2, 28(sp)
+; RV32IM-NEXT:    addi a0, sp, 40
+; RV32IM-NEXT:    addi a1, sp, 24
+; RV32IM-NEXT:    addi a2, sp, 8
+; RV32IM-NEXT:    sw a3, 24(sp)
+; RV32IM-NEXT:    call __multi3@plt
+; RV32IM-NEXT:    lw a0, 52(sp)
+; RV32IM-NEXT:    lw a1, 48(sp)
+; RV32IM-NEXT:    lw a2, 44(sp)
+; RV32IM-NEXT:    lw a3, 40(sp)
+; RV32IM-NEXT:    sw a0, 12(s0)
+; RV32IM-NEXT:    sw a1, 8(s0)
+; RV32IM-NEXT:    sw a2, 4(s0)
+; RV32IM-NEXT:    sw a3, 0(s0)
+; RV32IM-NEXT:    lw s0, 56(sp) # 4-byte Folded Reload
+; RV32IM-NEXT:    lw ra, 60(sp) # 4-byte Folded Reload
+; RV32IM-NEXT:    addi sp, sp, 64
+; RV32IM-NEXT:    ret
+;
+; RV64I-LABEL: muli128_m63:
+; RV64I:       # %bb.0:
+; RV64I-NEXT:    slli a2, a0, 6
+; RV64I-NEXT:    sltu a3, a0, a2
+; RV64I-NEXT:    srli a4, a0, 58
+; RV64I-NEXT:    slli a5, a1, 6
+; RV64I-NEXT:    or a4, a5, a4
+; RV64I-NEXT:    sub a1, a1, a4
+; RV64I-NEXT:    sub a1, a1, a3
+; RV64I-NEXT:    sub a0, a0, a2
+; RV64I-NEXT:    ret
+;
+; RV64IM-LABEL: muli128_m63:
+; RV64IM:       # %bb.0:
+; RV64IM-NEXT:    slli a2, a0, 6
+; RV64IM-NEXT:    sltu a3, a0, a2
+; RV64IM-NEXT:    srli a4, a0, 58
+; RV64IM-NEXT:    slli a5, a1, 6
+; RV64IM-NEXT:    or a4, a5, a4
+; RV64IM-NEXT:    sub a1, a1, a4
+; RV64IM-NEXT:    sub a1, a1, a3
+; RV64IM-NEXT:    sub a0, a0, a2
+; RV64IM-NEXT:    ret
+  %1 = mul i128 %a, -63
+  ret i128 %1
+}