diff --git a/llvm/lib/Target/LoongArch/LoongArchISelDAGToDAG.cpp b/llvm/lib/Target/LoongArch/LoongArchISelDAGToDAG.cpp
--- a/llvm/lib/Target/LoongArch/LoongArchISelDAGToDAG.cpp
+++ b/llvm/lib/Target/LoongArch/LoongArchISelDAGToDAG.cpp
@@ -38,9 +38,14 @@
     break;
   case ISD::Constant: {
     int64_t Imm = cast<ConstantSDNode>(Node)->getSExtValue();
+    if (Imm == 0 && Node->getSimpleValueType(0) == GRLenVT) {
+      SDValue New = CurDAG->getCopyFromReg(CurDAG->getEntryNode(), DL,
+                                           LoongArch::R0, GRLenVT);
+      ReplaceNode(Node, New.getNode());
+      return;
+    }
     SDNode *Result = nullptr;
     SDValue SrcReg = CurDAG->getRegister(LoongArch::R0, GRLenVT);
-
     // The instructions in the sequence are handled here.
     for (LoongArchMatInt::Inst &Inst : LoongArchMatInt::generateInstSeq(Imm)) {
       SDValue SDImm = CurDAG->getTargetConstant(Inst.Imm, DL, GRLenVT);
diff --git a/llvm/test/CodeGen/LoongArch/imm.ll b/llvm/test/CodeGen/LoongArch/imm.ll
--- a/llvm/test/CodeGen/LoongArch/imm.ll
+++ b/llvm/test/CodeGen/LoongArch/imm.ll
@@ -1,5 +1,13 @@
 ; RUN: llc --mtriple=loongarch64 < %s | FileCheck %s
 
+define i64 @imm0() {
+; CHECK-LABEL: imm0:
+; CHECK:       # %bb.0:
+; CHECK-NEXT:    move $a0, $zero
+; CHECK-NEXT:    jirl $zero, $ra, 0
+  ret i64 0
+}
+
 define i64 @imm7ff0000000000000() {
 ; CHECK-LABEL: imm7ff0000000000000:
 ; CHECK:       # %bb.0:
diff --git a/llvm/test/CodeGen/LoongArch/ir-instruction/and.ll b/llvm/test/CodeGen/LoongArch/ir-instruction/and.ll
--- a/llvm/test/CodeGen/LoongArch/ir-instruction/and.ll
+++ b/llvm/test/CodeGen/LoongArch/ir-instruction/and.ll
@@ -84,12 +84,12 @@
 define i1 @and_i1_4(i1 %b) {
 ; LA32-LABEL: and_i1_4:
 ; LA32:       # %bb.0: # %entry
-; LA32-NEXT:    ori $a0, $zero, 0
+; LA32-NEXT:    move $a0, $zero
 ; LA32-NEXT:    jirl $zero, $ra, 0
 ;
 ; LA64-LABEL: and_i1_4:
 ; LA64:       # %bb.0: # %entry
-; LA64-NEXT:    ori $a0, $zero, 0
+; LA64-NEXT:    move $a0, $zero
 ; LA64-NEXT:    jirl $zero, $ra, 0
 entry:
   %r = and i1 4, %b
@@ -145,7 +145,7 @@
 ; LA32-LABEL: and_i64_4:
 ; LA32:       # %bb.0: # %entry
 ; LA32-NEXT:    andi $a0, $a0, 4
-; LA32-NEXT:    ori $a1, $zero, 0
+; LA32-NEXT:    move $a1, $zero
 ; LA32-NEXT:    jirl $zero, $ra, 0
 ;
 ; LA64-LABEL: and_i64_4:
@@ -219,7 +219,7 @@
 ; LA32-LABEL: and_i64_31:
 ; LA32:       # %bb.0: # %entry
 ; LA32-NEXT:    andi $a0, $a0, 31
-; LA32-NEXT:    ori $a1, $zero, 0
+; LA32-NEXT:    move $a1, $zero
 ; LA32-NEXT:    jirl $zero, $ra, 0
 ;
 ; LA64-LABEL: and_i64_31:
@@ -293,7 +293,7 @@
 ; LA32-LABEL: and_i64_65:
 ; LA32:       # %bb.0: # %entry
 ; LA32-NEXT:    andi $a0, $a0, 65
-; LA32-NEXT:    ori $a1, $zero, 0
+; LA32-NEXT:    move $a1, $zero
 ; LA32-NEXT:    jirl $zero, $ra, 0
 ;
 ; LA64-LABEL: and_i64_65:
@@ -365,7 +365,7 @@
 ; LA32-LABEL: and_i64_255:
 ; LA32:       # %bb.0: # %entry
 ; LA32-NEXT:    andi $a0, $a0, 255
-; LA32-NEXT:    ori $a1, $zero, 0
+; LA32-NEXT:    move $a1, $zero
 ; LA32-NEXT:    jirl $zero, $ra, 0
 ;
 ; LA64-LABEL: and_i64_255:
@@ -380,12 +380,12 @@
 define i1 @and_i1_256(i1 %b) {
 ; LA32-LABEL: and_i1_256:
 ; LA32:       # %bb.0: # %entry
-; LA32-NEXT:    ori $a0, $zero, 0
+; LA32-NEXT:    move $a0, $zero
 ; LA32-NEXT:    jirl $zero, $ra, 0
 ;
 ; LA64-LABEL: and_i1_256:
 ; LA64:       # %bb.0: # %entry
-; LA64-NEXT:    ori $a0, $zero, 0
+; LA64-NEXT:    move $a0, $zero
 ; LA64-NEXT:    jirl $zero, $ra, 0
 entry:
   %r = and i1 256, %b
@@ -395,12 +395,12 @@
 define i8 @and_i8_256(i8 %b) {
 ; LA32-LABEL: and_i8_256:
 ; LA32:       # %bb.0: # %entry
-; LA32-NEXT:    ori $a0, $zero, 0
+; LA32-NEXT:    move $a0, $zero
 ; LA32-NEXT:    jirl $zero, $ra, 0
 ;
 ; LA64-LABEL: and_i8_256:
 ; LA64:       # %bb.0: # %entry
-; LA64-NEXT:    ori $a0, $zero, 0
+; LA64-NEXT:    move $a0, $zero
 ; LA64-NEXT:    jirl $zero, $ra, 0
 entry:
   %r = and i8 256, %b
@@ -441,7 +441,7 @@
 ; LA32-LABEL: and_i64_256:
 ; LA32:       # %bb.0: # %entry
 ; LA32-NEXT:    andi $a0, $a0, 256
-; LA32-NEXT:    ori $a1, $zero, 0
+; LA32-NEXT:    move $a1, $zero
 ; LA32-NEXT:    jirl $zero, $ra, 0
 ;
 ; LA64-LABEL: and_i64_256:
@@ -456,12 +456,12 @@
 define i1 @and_i1_2048(i1 %b) {
 ; LA32-LABEL: and_i1_2048:
 ; LA32:       # %bb.0: # %entry
-; LA32-NEXT:    ori $a0, $zero, 0
+; LA32-NEXT:    move $a0, $zero
 ; LA32-NEXT:    jirl $zero, $ra, 0
 ;
 ; LA64-LABEL: and_i1_2048:
 ; LA64:       # %bb.0: # %entry
-; LA64-NEXT:    ori $a0, $zero, 0
+; LA64-NEXT:    move $a0, $zero
 ; LA64-NEXT:    jirl $zero, $ra, 0
 entry:
   %r = and i1 2048, %b
@@ -471,12 +471,12 @@
 define i8 @and_i8_2048(i8 %b) {
 ; LA32-LABEL: and_i8_2048:
 ; LA32:       # %bb.0: # %entry
-; LA32-NEXT:    ori $a0, $zero, 0
+; LA32-NEXT:    move $a0, $zero
 ; LA32-NEXT:    jirl $zero, $ra, 0
 ;
 ; LA64-LABEL: and_i8_2048:
 ; LA64:       # %bb.0: # %entry
-; LA64-NEXT:    ori $a0, $zero, 0
+; LA64-NEXT:    move $a0, $zero
 ; LA64-NEXT:    jirl $zero, $ra, 0
 entry:
   %r = and i8 2048, %b
@@ -517,7 +517,7 @@
 ; LA32-LABEL: and_i64_2048:
 ; LA32:       # %bb.0: # %entry
 ; LA32-NEXT:    andi $a0, $a0, 2048
-; LA32-NEXT:    ori $a1, $zero, 0
+; LA32-NEXT:    move $a1, $zero
 ; LA32-NEXT:    jirl $zero, $ra, 0
 ;
 ; LA64-LABEL: and_i64_2048:
@@ -532,12 +532,12 @@
 define i1 @and_i1_4096(i1 %b) {
 ; LA32-LABEL: and_i1_4096:
 ; LA32:       # %bb.0: # %entry
-; LA32-NEXT:    ori $a0, $zero, 0
+; LA32-NEXT:    move $a0, $zero
 ; LA32-NEXT:    jirl $zero, $ra, 0
 ;
 ; LA64-LABEL: and_i1_4096:
 ; LA64:       # %bb.0: # %entry
-; LA64-NEXT:    ori $a0, $zero, 0
+; LA64-NEXT:    move $a0, $zero
 ; LA64-NEXT:    jirl $zero, $ra, 0
 entry:
   %r = and i1 4096, %b
@@ -547,12 +547,12 @@
 define i8 @and_i8_4096(i8 %b) {
 ; LA32-LABEL: and_i8_4096:
 ; LA32:       # %bb.0: # %entry
-; LA32-NEXT:    ori $a0, $zero, 0
+; LA32-NEXT:    move $a0, $zero
 ; LA32-NEXT:    jirl $zero, $ra, 0
 ;
 ; LA64-LABEL: and_i8_4096:
 ; LA64:       # %bb.0: # %entry
-; LA64-NEXT:    ori $a0, $zero, 0
+; LA64-NEXT:    move $a0, $zero
 ; LA64-NEXT:    jirl $zero, $ra, 0
 entry:
   %r = and i8 4096, %b
@@ -598,7 +598,7 @@
 ; LA32:       # %bb.0: # %entry
 ; LA32-NEXT:    lu12i.w $a1, 1
 ; LA32-NEXT:    and $a0, $a0, $a1
-; LA32-NEXT:    ori $a1, $zero, 0
+; LA32-NEXT:    move $a1, $zero
 ; LA32-NEXT:    jirl $zero, $ra, 0
 ;
 ; LA64-LABEL: and_i64_4096:
diff --git a/llvm/test/CodeGen/LoongArch/ir-instruction/fcmp-dbl.ll b/llvm/test/CodeGen/LoongArch/ir-instruction/fcmp-dbl.ll
--- a/llvm/test/CodeGen/LoongArch/ir-instruction/fcmp-dbl.ll
+++ b/llvm/test/CodeGen/LoongArch/ir-instruction/fcmp-dbl.ll
@@ -7,12 +7,12 @@
 define i1 @fcmp_false(double %a, double %b) {
 ; LA32-LABEL: fcmp_false:
 ; LA32:       # %bb.0:
-; LA32-NEXT:    ori $a0, $zero, 0
+; LA32-NEXT:    move $a0, $zero
 ; LA32-NEXT:    jirl $zero, $ra, 0
 ;
 ; LA64-LABEL: fcmp_false:
 ; LA64:       # %bb.0:
-; LA64-NEXT:    ori $a0, $zero, 0
+; LA64-NEXT:    move $a0, $zero
 ; LA64-NEXT:    jirl $zero, $ra, 0
   %cmp = fcmp false double %a, %b
   ret i1 %cmp
diff --git a/llvm/test/CodeGen/LoongArch/ir-instruction/fcmp-flt.ll b/llvm/test/CodeGen/LoongArch/ir-instruction/fcmp-flt.ll
--- a/llvm/test/CodeGen/LoongArch/ir-instruction/fcmp-flt.ll
+++ b/llvm/test/CodeGen/LoongArch/ir-instruction/fcmp-flt.ll
@@ -7,12 +7,12 @@
 define i1 @fcmp_false(float %a, float %b) {
 ; LA32-LABEL: fcmp_false:
 ; LA32:       # %bb.0:
-; LA32-NEXT:    ori $a0, $zero, 0
+; LA32-NEXT:    move $a0, $zero
 ; LA32-NEXT:    jirl $zero, $ra, 0
 ;
 ; LA64-LABEL: fcmp_false:
 ; LA64:       # %bb.0:
-; LA64-NEXT:    ori $a0, $zero, 0
+; LA64-NEXT:    move $a0, $zero
 ; LA64-NEXT:    jirl $zero, $ra, 0
   %cmp = fcmp false float %a, %b
   ret i1 %cmp
diff --git a/llvm/test/CodeGen/LoongArch/ir-instruction/sext-zext-trunc.ll b/llvm/test/CodeGen/LoongArch/ir-instruction/sext-zext-trunc.ll
--- a/llvm/test/CodeGen/LoongArch/ir-instruction/sext-zext-trunc.ll
+++ b/llvm/test/CodeGen/LoongArch/ir-instruction/sext-zext-trunc.ll
@@ -7,15 +7,13 @@
 ; LA32-LABEL: sext_i1_to_i8:
 ; LA32:       # %bb.0:
 ; LA32-NEXT:    andi $a0, $a0, 1
-; LA32-NEXT:    ori $a1, $zero, 0
-; LA32-NEXT:    sub.w $a0, $a1, $a0
+; LA32-NEXT:    sub.w $a0, $zero, $a0
 ; LA32-NEXT:    jirl $zero, $ra, 0
 ;
 ; LA64-LABEL: sext_i1_to_i8:
 ; LA64:       # %bb.0:
 ; LA64-NEXT:    andi $a0, $a0, 1
-; LA64-NEXT:    ori $a1, $zero, 0
-; LA64-NEXT:    sub.d $a0, $a1, $a0
+; LA64-NEXT:    sub.d $a0, $zero, $a0
 ; LA64-NEXT:    jirl $zero, $ra, 0
   %1 = sext i1 %a to i8
   ret i8 %1
@@ -25,15 +23,13 @@
 ; LA32-LABEL: sext_i1_to_i16:
 ; LA32:       # %bb.0:
 ; LA32-NEXT:    andi $a0, $a0, 1
-; LA32-NEXT:    ori $a1, $zero, 0
-; LA32-NEXT:    sub.w $a0, $a1, $a0
+; LA32-NEXT:    sub.w $a0, $zero, $a0
 ; LA32-NEXT:    jirl $zero, $ra, 0
 ;
 ; LA64-LABEL: sext_i1_to_i16:
 ; LA64:       # %bb.0:
 ; LA64-NEXT:    andi $a0, $a0, 1
-; LA64-NEXT:    ori $a1, $zero, 0
-; LA64-NEXT:    sub.d $a0, $a1, $a0
+; LA64-NEXT:    sub.d $a0, $zero, $a0
 ; LA64-NEXT:    jirl $zero, $ra, 0
   %1 = sext i1 %a to i16
   ret i16 %1
@@ -43,15 +39,13 @@
 ; LA32-LABEL: sext_i1_to_i32:
 ; LA32:       # %bb.0:
 ; LA32-NEXT:    andi $a0, $a0, 1
-; LA32-NEXT:    ori $a1, $zero, 0
-; LA32-NEXT:    sub.w $a0, $a1, $a0
+; LA32-NEXT:    sub.w $a0, $zero, $a0
 ; LA32-NEXT:    jirl $zero, $ra, 0
 ;
 ; LA64-LABEL: sext_i1_to_i32:
 ; LA64:       # %bb.0:
 ; LA64-NEXT:    andi $a0, $a0, 1
-; LA64-NEXT:    ori $a1, $zero, 0
-; LA64-NEXT:    sub.d $a0, $a1, $a0
+; LA64-NEXT:    sub.d $a0, $zero, $a0
 ; LA64-NEXT:    jirl $zero, $ra, 0
   %1 = sext i1 %a to i32
   ret i32 %1
@@ -61,16 +55,14 @@
 ; LA32-LABEL: sext_i1_to_i64:
 ; LA32:       # %bb.0:
 ; LA32-NEXT:    andi $a0, $a0, 1
-; LA32-NEXT:    ori $a1, $zero, 0
-; LA32-NEXT:    sub.w $a0, $a1, $a0
+; LA32-NEXT:    sub.w $a0, $zero, $a0
 ; LA32-NEXT:    move $a1, $a0
 ; LA32-NEXT:    jirl $zero, $ra, 0
 ;
 ; LA64-LABEL: sext_i1_to_i64:
 ; LA64:       # %bb.0:
 ; LA64-NEXT:    andi $a0, $a0, 1
-; LA64-NEXT:    ori $a1, $zero, 0
-; LA64-NEXT:    sub.d $a0, $a1, $a0
+; LA64-NEXT:    sub.d $a0, $zero, $a0
 ; LA64-NEXT:    jirl $zero, $ra, 0
   %1 = sext i1 %a to i64
   ret i64 %1
@@ -208,7 +200,7 @@
 ; LA32-LABEL: zext_i1_to_i64:
 ; LA32:       # %bb.0:
 ; LA32-NEXT:    andi $a0, $a0, 1
-; LA32-NEXT:    ori $a1, $zero, 0
+; LA32-NEXT:    move $a1, $zero
 ; LA32-NEXT:    jirl $zero, $ra, 0
 ;
 ; LA64-LABEL: zext_i1_to_i64:
@@ -251,7 +243,7 @@
 ; LA32-LABEL: zext_i8_to_i64:
 ; LA32:       # %bb.0:
 ; LA32-NEXT:    andi $a0, $a0, 255
-; LA32-NEXT:    ori $a1, $zero, 0
+; LA32-NEXT:    move $a1, $zero
 ; LA32-NEXT:    jirl $zero, $ra, 0
 ;
 ; LA64-LABEL: zext_i8_to_i64:
@@ -286,7 +278,7 @@
 ; LA32-NEXT:    lu12i.w $a1, 15
 ; LA32-NEXT:    ori $a1, $a1, 4095
 ; LA32-NEXT:    and $a0, $a0, $a1
-; LA32-NEXT:    ori $a1, $zero, 0
+; LA32-NEXT:    move $a1, $zero
 ; LA32-NEXT:    jirl $zero, $ra, 0
 ;
 ; LA64-LABEL: zext_i16_to_i64:
@@ -302,7 +294,7 @@
 define i64 @zext_i32_to_i64(i32 %a) {
 ; LA32-LABEL: zext_i32_to_i64:
 ; LA32:       # %bb.0:
-; LA32-NEXT:    ori $a1, $zero, 0
+; LA32-NEXT:    move $a1, $zero
 ; LA32-NEXT:    jirl $zero, $ra, 0
 ;
 ; LA64-LABEL: zext_i32_to_i64: