diff --git a/llvm/lib/Target/CSKY/CSKY.td b/llvm/lib/Target/CSKY/CSKY.td
index e5ac106c9b59a..9809caa8bd8f6 100644
--- a/llvm/lib/Target/CSKY/CSKY.td
+++ b/llvm/lib/Target/CSKY/CSKY.td
@@ -40,17 +40,17 @@ def HasFdivdu : Predicate<"Subtarget->hasFdivdu()">,
 
 def FeatureFPUV3_HI
     : SubtargetFeature<"fpuv3_hi", "HasFPUv3HalfWord", "true",
-                       "Enable FPUv3 harf word converting instructions">;
+                       "Enable FPUv3 half word converting instructions">;
 def HasFPUv3_HI : Predicate<"Subtarget->hasFPUv3HalfWord()">,
                   AssemblerPredicate<(all_of FeatureFPUV3_HI),
-                  "Enable FPUv3 harf word converting instructions">;
+                  "Enable FPUv3 half word converting instructions">;
 
 def FeatureFPUV3_HF
     : SubtargetFeature<"fpuv3_hf", "HasFPUv3HalfFloat", "true",
-                       "Enable FPUv3 harf precision operate instructions">;
+                       "Enable FPUv3 half precision operate instructions">;
 def HasFPUv3_HF : Predicate<"Subtarget->hasFPUv3HalfFloat()">,
                   AssemblerPredicate<(all_of FeatureFPUV3_HF),
-                  "Enable FPUv3 harf precision operate instructions">;
+                  "Enable FPUv3 half precision operate instructions">;
 
 def FeatureFPUV3_SF
     : SubtargetFeature<"fpuv3_sf", "HasFPUv3SingleFloat", "true",
diff --git a/llvm/lib/Target/CSKY/CSKYISelLowering.cpp b/llvm/lib/Target/CSKY/CSKYISelLowering.cpp
index 2c8649a3b6ad1..4a2df7cd4d021 100644
--- a/llvm/lib/Target/CSKY/CSKYISelLowering.cpp
+++ b/llvm/lib/Target/CSKY/CSKYISelLowering.cpp
@@ -116,9 +116,9 @@ CSKYTargetLowering::CSKYTargetLowering(const TargetMachine &TM,
       ISD::SETUGE, ISD::SETULT, ISD::SETULE,
   };
 
-  ISD::NodeType FPOpToExpand[] = {ISD::FSIN, ISD::FCOS, ISD::FSINCOS,
-                                  ISD::FPOW, ISD::FREM, ISD::FCOPYSIGN,
-                                  ISD::FP16_TO_FP, ISD::FP_TO_FP16};
+  ISD::NodeType FPOpToExpand[] = {
+      ISD::FSIN, ISD::FCOS,      ISD::FSINCOS,    ISD::FPOW,
+      ISD::FREM, ISD::FCOPYSIGN, ISD::FP16_TO_FP, ISD::FP_TO_FP16};
 
   if (STI.useHardFloat()) {
 
diff --git a/llvm/test/CodeGen/CSKY/mul-imm.ll b/llvm/test/CodeGen/CSKY/mul-imm.ll
new file mode 100644
index 0000000000000..c87e527430de5
--- /dev/null
+++ b/llvm/test/CodeGen/CSKY/mul-imm.ll
@@ -0,0 +1,399 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py UTC_ARGS: --version 2
+; RUN: llc -verify-machineinstrs -csky-no-aliases -mattr=+e2 < %s -mtriple=csky | FileCheck %s
+; RUN: llc -verify-machineinstrs -csky-no-aliases < %s -mtriple=csky | FileCheck %s --check-prefix=GENERIC
+
+;; This file shows if a multiplication can be simplified to an addition/subtraction
+;; of left shifts.
+
+define i32 @mul_i32_4097(i32 %x) {
+; CHECK-LABEL: mul_i32_4097:
+; CHECK:       # %bb.0: # %entry
+; CHECK-NEXT:    movi32 a1, 4097
+; CHECK-NEXT:    mult16 a0, a1
+; CHECK-NEXT:    rts16
+;
+; GENERIC-LABEL: mul_i32_4097:
+; GENERIC:       # %bb.0: # %entry
+; GENERIC-NEXT:    .cfi_def_cfa_offset 0
+; GENERIC-NEXT:    subi16 sp, sp, 4
+; GENERIC-NEXT:    .cfi_def_cfa_offset 4
+; GENERIC-NEXT:    movi16 a1, 0
+; GENERIC-NEXT:    lsli16 a2, a1, 24
+; GENERIC-NEXT:    lsli16 a1, a1, 16
+; GENERIC-NEXT:    or16 a1, a2
+; GENERIC-NEXT:    movi16 a2, 16
+; GENERIC-NEXT:    lsli16 a2, a2, 8
+; GENERIC-NEXT:    or16 a2, a1
+; GENERIC-NEXT:    movi16 a1, 1
+; GENERIC-NEXT:    or16 a1, a2
+; GENERIC-NEXT:    mult16 a0, a1
+; GENERIC-NEXT:    addi16 sp, sp, 4
+; GENERIC-NEXT:    rts16
+entry:
+  %y = mul nsw i32 %x, 4097
+  ret i32 %y
+}
+
+define i32 @mul_i32_4095(i32 %x) {
+; CHECK-LABEL: mul_i32_4095:
+; CHECK:       # %bb.0: # %entry
+; CHECK-NEXT:    movi32 a1, 4095
+; CHECK-NEXT:    mult16 a0, a1
+; CHECK-NEXT:    rts16
+;
+; GENERIC-LABEL: mul_i32_4095:
+; GENERIC:       # %bb.0: # %entry
+; GENERIC-NEXT:    .cfi_def_cfa_offset 0
+; GENERIC-NEXT:    subi16 sp, sp, 4
+; GENERIC-NEXT:    .cfi_def_cfa_offset 4
+; GENERIC-NEXT:    movi16 a1, 0
+; GENERIC-NEXT:    lsli16 a2, a1, 24
+; GENERIC-NEXT:    lsli16 a1, a1, 16
+; GENERIC-NEXT:    or16 a1, a2
+; GENERIC-NEXT:    movi16 a2, 15
+; GENERIC-NEXT:    lsli16 a2, a2, 8
+; GENERIC-NEXT:    or16 a2, a1
+; GENERIC-NEXT:    movi16 a1, 255
+; GENERIC-NEXT:    or16 a1, a2
+; GENERIC-NEXT:    mult16 a0, a1
+; GENERIC-NEXT:    addi16 sp, sp, 4
+; GENERIC-NEXT:    rts16
+entry:
+  %y = mul nsw i32 %x, 4095
+  ret i32 %y
+}
+
+define i32 @mul_i32_minus_4095(i32 %x) {
+; CHECK-LABEL: mul_i32_minus_4095:
+; CHECK:       # %bb.0: # %entry
+; CHECK-NEXT:    movih32 a1, 65535
+; CHECK-NEXT:    ori32 a1, a1, 61441
+; CHECK-NEXT:    mult16 a0, a1
+; CHECK-NEXT:    rts16
+;
+; GENERIC-LABEL: mul_i32_minus_4095:
+; GENERIC:       # %bb.0: # %entry
+; GENERIC-NEXT:    .cfi_def_cfa_offset 0
+; GENERIC-NEXT:    subi16 sp, sp, 4
+; GENERIC-NEXT:    .cfi_def_cfa_offset 4
+; GENERIC-NEXT:    movi16 a1, 255
+; GENERIC-NEXT:    lsli16 a2, a1, 24
+; GENERIC-NEXT:    lsli16 a1, a1, 16
+; GENERIC-NEXT:    or16 a1, a2
+; GENERIC-NEXT:    movi16 a2, 240
+; GENERIC-NEXT:    lsli16 a2, a2, 8
+; GENERIC-NEXT:    or16 a2, a1
+; GENERIC-NEXT:    movi16 a1, 1
+; GENERIC-NEXT:    or16 a1, a2
+; GENERIC-NEXT:    mult16 a0, a1
+; GENERIC-NEXT:    addi16 sp, sp, 4
+; GENERIC-NEXT:    rts16
+entry:
+  %y = mul nsw i32 %x, -4095
+  ret i32 %y
+}
+
+define i16 @mul_i16_4097(i16 %x) {
+; CHECK-LABEL: mul_i16_4097:
+; CHECK:       # %bb.0: # %entry
+; CHECK-NEXT:    movi32 a1, 4097
+; CHECK-NEXT:    mult16 a0, a1
+; CHECK-NEXT:    rts16
+;
+; GENERIC-LABEL: mul_i16_4097:
+; GENERIC:       # %bb.0: # %entry
+; GENERIC-NEXT:    .cfi_def_cfa_offset 0
+; GENERIC-NEXT:    subi16 sp, sp, 4
+; GENERIC-NEXT:    .cfi_def_cfa_offset 4
+; GENERIC-NEXT:    movi16 a1, 0
+; GENERIC-NEXT:    lsli16 a2, a1, 24
+; GENERIC-NEXT:    lsli16 a1, a1, 16
+; GENERIC-NEXT:    or16 a1, a2
+; GENERIC-NEXT:    movi16 a2, 16
+; GENERIC-NEXT:    lsli16 a2, a2, 8
+; GENERIC-NEXT:    or16 a2, a1
+; GENERIC-NEXT:    movi16 a1, 1
+; GENERIC-NEXT:    or16 a1, a2
+; GENERIC-NEXT:    mult16 a0, a1
+; GENERIC-NEXT:    addi16 sp, sp, 4
+; GENERIC-NEXT:    rts16
+entry:
+  %y = mul nsw i16 %x, 4097
+  ret i16 %y
+}
+
+define i16 @mul_i16_4095(i16 %x) {
+; CHECK-LABEL: mul_i16_4095:
+; CHECK:       # %bb.0: # %entry
+; CHECK-NEXT:    movi32 a1, 4095
+; CHECK-NEXT:    mult16 a0, a1
+; CHECK-NEXT:    rts16
+;
+; GENERIC-LABEL: mul_i16_4095:
+; GENERIC:       # %bb.0: # %entry
+; GENERIC-NEXT:    .cfi_def_cfa_offset 0
+; GENERIC-NEXT:    subi16 sp, sp, 4
+; GENERIC-NEXT:    .cfi_def_cfa_offset 4
+; GENERIC-NEXT:    movi16 a1, 0
+; GENERIC-NEXT:    lsli16 a2, a1, 24
+; GENERIC-NEXT:    lsli16 a1, a1, 16
+; GENERIC-NEXT:    or16 a1, a2
+; GENERIC-NEXT:    movi16 a2, 15
+; GENERIC-NEXT:    lsli16 a2, a2, 8
+; GENERIC-NEXT:    or16 a2, a1
+; GENERIC-NEXT:    movi16 a1, 255
+; GENERIC-NEXT:    or16 a1, a2
+; GENERIC-NEXT:    mult16 a0, a1
+; GENERIC-NEXT:    addi16 sp, sp, 4
+; GENERIC-NEXT:    rts16
+entry:
+  %y = mul nsw i16 %x, 4095
+  ret i16 %y
+}
+
+define i16 @mul_i16_minus_4095(i16 %x) {
+; CHECK-LABEL: mul_i16_minus_4095:
+; CHECK:       # %bb.0: # %entry
+; CHECK-NEXT:    movih32 a1, 65535
+; CHECK-NEXT:    ori32 a1, a1, 61441
+; CHECK-NEXT:    mult16 a0, a1
+; CHECK-NEXT:    rts16
+;
+; GENERIC-LABEL: mul_i16_minus_4095:
+; GENERIC:       # %bb.0: # %entry
+; GENERIC-NEXT:    .cfi_def_cfa_offset 0
+; GENERIC-NEXT:    subi16 sp, sp, 4
+; GENERIC-NEXT:    .cfi_def_cfa_offset 4
+; GENERIC-NEXT:    movi16 a1, 255
+; GENERIC-NEXT:    lsli16 a2, a1, 24
+; GENERIC-NEXT:    lsli16 a1, a1, 16
+; GENERIC-NEXT:    or16 a1, a2
+; GENERIC-NEXT:    movi16 a2, 240
+; GENERIC-NEXT:    lsli16 a2, a2, 8
+; GENERIC-NEXT:    or16 a2, a1
+; GENERIC-NEXT:    movi16 a1, 1
+; GENERIC-NEXT:    or16 a1, a2
+; GENERIC-NEXT:    mult16 a0, a1
+; GENERIC-NEXT:    addi16 sp, sp, 4
+; GENERIC-NEXT:    rts16
+entry:
+  %y = mul nsw i16 %x, -4095
+  ret i16 %y
+}
+
+define i8 @mul_i8_65(i8 %x) {
+; CHECK-LABEL: mul_i8_65:
+; CHECK:       # %bb.0: # %entry
+; CHECK-NEXT:    movi16 a1, 65
+; CHECK-NEXT:    mult16 a0, a1
+; CHECK-NEXT:    rts16
+;
+; GENERIC-LABEL: mul_i8_65:
+; GENERIC:       # %bb.0: # %entry
+; GENERIC-NEXT:    .cfi_def_cfa_offset 0
+; GENERIC-NEXT:    subi16 sp, sp, 4
+; GENERIC-NEXT:    .cfi_def_cfa_offset 4
+; GENERIC-NEXT:    movi16 a1, 65
+; GENERIC-NEXT:    mult16 a0, a1
+; GENERIC-NEXT:    addi16 sp, sp, 4
+; GENERIC-NEXT:    rts16
+entry:
+  %y = mul nsw i8 %x, 65
+  ret i8 %y
+}
+
+define i8 @mul_i8_63(i8 %x) {
+; CHECK-LABEL: mul_i8_63:
+; CHECK:       # %bb.0: # %entry
+; CHECK-NEXT:    movi16 a1, 63
+; CHECK-NEXT:    mult16 a0, a1
+; CHECK-NEXT:    rts16
+;
+; GENERIC-LABEL: mul_i8_63:
+; GENERIC:       # %bb.0: # %entry
+; GENERIC-NEXT:    .cfi_def_cfa_offset 0
+; GENERIC-NEXT:    subi16 sp, sp, 4
+; GENERIC-NEXT:    .cfi_def_cfa_offset 4
+; GENERIC-NEXT:    movi16 a1, 63
+; GENERIC-NEXT:    mult16 a0, a1
+; GENERIC-NEXT:    addi16 sp, sp, 4
+; GENERIC-NEXT:    rts16
+entry:
+  %y = mul nsw i8 %x, 63
+  ret i8 %y
+}
+
+define i8 @mul_i8_minus_63(i8 %x) {
+; CHECK-LABEL: mul_i8_minus_63:
+; CHECK:       # %bb.0: # %entry
+; CHECK-NEXT:    movih32 a1, 65535
+; CHECK-NEXT:    ori32 a1, a1, 65473
+; CHECK-NEXT:    mult16 a0, a1
+; CHECK-NEXT:    rts16
+;
+; GENERIC-LABEL: mul_i8_minus_63:
+; GENERIC:       # %bb.0: # %entry
+; GENERIC-NEXT:    .cfi_def_cfa_offset 0
+; GENERIC-NEXT:    subi16 sp, sp, 4
+; GENERIC-NEXT:    .cfi_def_cfa_offset 4
+; GENERIC-NEXT:    movi16 a1, 255
+; GENERIC-NEXT:    lsli16 a2, a1, 24
+; GENERIC-NEXT:    lsli16 a3, a1, 16
+; GENERIC-NEXT:    or16 a3, a2
+; GENERIC-NEXT:    lsli16 a1, a1, 8
+; GENERIC-NEXT:    or16 a1, a3
+; GENERIC-NEXT:    movi16 a2, 193
+; GENERIC-NEXT:    or16 a2, a1
+; GENERIC-NEXT:    mult16 a0, a2
+; GENERIC-NEXT:    addi16 sp, sp, 4
+; GENERIC-NEXT:    rts16
+entry:
+  %y = mul nsw i8 %x, -63
+  ret i8 %y
+}
+
+define i32 @mul_i32_minus_4097(i32 %x) {
+; CHECK-LABEL: mul_i32_minus_4097:
+; CHECK:       # %bb.0: # %entry
+; CHECK-NEXT:    movih32 a1, 65535
+; CHECK-NEXT:    ori32 a1, a1, 61439
+; CHECK-NEXT:    mult16 a0, a1
+; CHECK-NEXT:    rts16
+;
+; GENERIC-LABEL: mul_i32_minus_4097:
+; GENERIC:       # %bb.0: # %entry
+; GENERIC-NEXT:    .cfi_def_cfa_offset 0
+; GENERIC-NEXT:    subi16 sp, sp, 4
+; GENERIC-NEXT:    .cfi_def_cfa_offset 4
+; GENERIC-NEXT:    movi16 a1, 255
+; GENERIC-NEXT:    lsli16 a2, a1, 24
+; GENERIC-NEXT:    lsli16 a3, a1, 16
+; GENERIC-NEXT:    or16 a3, a2
+; GENERIC-NEXT:    movi16 a2, 239
+; GENERIC-NEXT:    lsli16 a2, a2, 8
+; GENERIC-NEXT:    or16 a2, a3
+; GENERIC-NEXT:    or16 a2, a1
+; GENERIC-NEXT:    mult16 a0, a2
+; GENERIC-NEXT:    addi16 sp, sp, 4
+; GENERIC-NEXT:    rts16
+entry:
+  %y = mul nsw i32 %x, -4097
+  ret i32 %y
+}
+
+define i16 @mul_i16_minus_4097(i16 %x) {
+; CHECK-LABEL: mul_i16_minus_4097:
+; CHECK:       # %bb.0: # %entry
+; CHECK-NEXT:    movih32 a1, 65535
+; CHECK-NEXT:    ori32 a1, a1, 61439
+; CHECK-NEXT:    mult16 a0, a1
+; CHECK-NEXT:    rts16
+;
+; GENERIC-LABEL: mul_i16_minus_4097:
+; GENERIC:       # %bb.0: # %entry
+; GENERIC-NEXT:    .cfi_def_cfa_offset 0
+; GENERIC-NEXT:    subi16 sp, sp, 4
+; GENERIC-NEXT:    .cfi_def_cfa_offset 4
+; GENERIC-NEXT:    movi16 a1, 255
+; GENERIC-NEXT:    lsli16 a2, a1, 24
+; GENERIC-NEXT:    lsli16 a3, a1, 16
+; GENERIC-NEXT:    or16 a3, a2
+; GENERIC-NEXT:    movi16 a2, 239
+; GENERIC-NEXT:    lsli16 a2, a2, 8
+; GENERIC-NEXT:    or16 a2, a3
+; GENERIC-NEXT:    or16 a2, a1
+; GENERIC-NEXT:    mult16 a0, a2
+; GENERIC-NEXT:    addi16 sp, sp, 4
+; GENERIC-NEXT:    rts16
+entry:
+  %y = mul nsw i16 %x, -4097
+  ret i16 %y
+}
+
+define i8 @mul_i8_minus_65(i8 %x) {
+; CHECK-LABEL: mul_i8_minus_65:
+; CHECK:       # %bb.0: # %entry
+; CHECK-NEXT:    movih32 a1, 65535
+; CHECK-NEXT:    ori32 a1, a1, 65471
+; CHECK-NEXT:    mult16 a0, a1
+; CHECK-NEXT:    rts16
+;
+; GENERIC-LABEL: mul_i8_minus_65:
+; GENERIC:       # %bb.0: # %entry
+; GENERIC-NEXT:    .cfi_def_cfa_offset 0
+; GENERIC-NEXT:    subi16 sp, sp, 4
+; GENERIC-NEXT:    .cfi_def_cfa_offset 4
+; GENERIC-NEXT:    movi16 a1, 255
+; GENERIC-NEXT:    lsli16 a2, a1, 24
+; GENERIC-NEXT:    lsli16 a3, a1, 16
+; GENERIC-NEXT:    or16 a3, a2
+; GENERIC-NEXT:    lsli16 a1, a1, 8
+; GENERIC-NEXT:    or16 a1, a3
+; GENERIC-NEXT:    movi16 a2, 191
+; GENERIC-NEXT:    or16 a2, a1
+; GENERIC-NEXT:    mult16 a0, a2
+; GENERIC-NEXT:    addi16 sp, sp, 4
+; GENERIC-NEXT:    rts16
+entry:
+  %y = mul nsw i8 %x, -65
+  ret i8 %y
+}
+
+;; This case can not be optimized, due to the data type exceeds.
+define i64 @mul_i64_4097(i64 %x) {
+; CHECK-LABEL: mul_i64_4097:
+; CHECK:       # %bb.0: # %entry
+; CHECK-NEXT:    subi16 sp, sp, 4
+; CHECK-NEXT:    .cfi_def_cfa_offset 4
+; CHECK-NEXT:    st32.w lr, (sp, 0) # 4-byte Folded Spill
+; CHECK-NEXT:    .cfi_offset lr, -4
+; CHECK-NEXT:    .cfi_def_cfa_offset 4
+; CHECK-NEXT:    lrw32 t0, [.LCPI12_0]
+; CHECK-NEXT:    movi32 a2, 4097
+; CHECK-NEXT:    movi16 a3, 0
+; CHECK-NEXT:    jsr16 t0
+; CHECK-NEXT:    ld32.w lr, (sp, 0) # 4-byte Folded Reload
+; CHECK-NEXT:    addi16 sp, sp, 4
+; CHECK-NEXT:    rts16
+; CHECK-NEXT:    .p2align 1
+; CHECK-NEXT:  # %bb.1:
+; CHECK-NEXT:    .p2align 2, 0x0
+; CHECK-NEXT:  .LCPI12_0:
+; CHECK-NEXT:    .long __muldi3
+;
+; GENERIC-LABEL: mul_i64_4097:
+; GENERIC:       # %bb.0: # %entry
+; GENERIC-NEXT:    subi16 sp, sp, 8
+; GENERIC-NEXT:    .cfi_def_cfa_offset 8
+; GENERIC-NEXT:    st16.w l0, (sp, 4) # 4-byte Folded Spill
+; GENERIC-NEXT:    st32.w lr, (sp, 0) # 4-byte Folded Spill
+; GENERIC-NEXT:    .cfi_offset l0, -4
+; GENERIC-NEXT:    .cfi_offset lr, -8
+; GENERIC-NEXT:    subi16 sp, sp, 4
+; GENERIC-NEXT:    .cfi_def_cfa_offset 12
+; GENERIC-NEXT:    movi16 a2, 0
+; GENERIC-NEXT:    lsli16 a3, a2, 24
+; GENERIC-NEXT:    lsli16 a2, a2, 16
+; GENERIC-NEXT:    or16 a2, a3
+; GENERIC-NEXT:    movi16 a3, 16
+; GENERIC-NEXT:    lsli16 a3, a3, 8
+; GENERIC-NEXT:    or16 a3, a2
+; GENERIC-NEXT:    movi16 a2, 1
+; GENERIC-NEXT:    or16 a2, a3
+; GENERIC-NEXT:    lrw32 l0, [.LCPI12_0]
+; GENERIC-NEXT:    movi16 a3, 0
+; GENERIC-NEXT:    jsr16 l0
+; GENERIC-NEXT:    addi16 sp, sp, 4
+; GENERIC-NEXT:    ld32.w lr, (sp, 0) # 4-byte Folded Reload
+; GENERIC-NEXT:    ld16.w l0, (sp, 4) # 4-byte Folded Reload
+; GENERIC-NEXT:    addi16 sp, sp, 8
+; GENERIC-NEXT:    rts16
+; GENERIC-NEXT:    .p2align 1
+; GENERIC-NEXT:  # %bb.1:
+; GENERIC-NEXT:    .p2align 2, 0x0
+; GENERIC-NEXT:  .LCPI12_0:
+; GENERIC-NEXT:    .long __muldi3
+entry:
+  %y = mul nsw i64 %x, 4097
+  ret i64 %y
+}