diff --git a/llvm/lib/Target/LoongArch/LoongArchInstrInfo.td b/llvm/lib/Target/LoongArch/LoongArchInstrInfo.td
--- a/llvm/lib/Target/LoongArch/LoongArchInstrInfo.td
+++ b/llvm/lib/Target/LoongArch/LoongArchInstrInfo.td
@@ -339,7 +339,7 @@
                "$rd, $rj, $imm14">;
 } // mayStore = 1
 
-let mayLoad = 1, mayStore = 1 in
+let mayLoad = 1, mayStore = 1, Constraints = "@earlyclobber $rd" in
 class AM_3R<bits<17> op, string opstr>
     : Fmt3R<op, (outs GPR:$rd), (ins GPR:$rk, GPR:$rj), opstr, "$rd, $rk, $rj">;
 
diff --git a/llvm/test/CodeGen/LoongArch/ir-instruction/atomicrmw.ll b/llvm/test/CodeGen/LoongArch/ir-instruction/atomicrmw.ll
--- a/llvm/test/CodeGen/LoongArch/ir-instruction/atomicrmw.ll
+++ b/llvm/test/CodeGen/LoongArch/ir-instruction/atomicrmw.ll
@@ -119,7 +119,8 @@
 ;
 ; LA64-LABEL: atomicrmw_xchg_i32_acquire:
 ; LA64:       # %bb.0:
-; LA64-NEXT:    amswap_db.w $a0, $a1, $a0
+; LA64-NEXT:    amswap_db.w $a2, $a1, $a0
+; LA64-NEXT:    move $a0, $a2
 ; LA64-NEXT:    ret
   %1 = atomicrmw xchg ptr %a, i32 %b acquire
   ret i32 %1
@@ -138,7 +139,8 @@
 ;
 ; LA64-LABEL: atomicrmw_xchg_i64_acquire:
 ; LA64:       # %bb.0:
-; LA64-NEXT:    amswap_db.d $a0, $a1, $a0
+; LA64-NEXT:    amswap_db.d $a2, $a1, $a0
+; LA64-NEXT:    move $a0, $a2
 ; LA64-NEXT:    ret
   %1 = atomicrmw xchg ptr %a, i64 %b acquire
   ret i64 %1
@@ -261,7 +263,8 @@
 ;
 ; LA64-LABEL: atomicrmw_add_i32_acquire:
 ; LA64:       # %bb.0:
-; LA64-NEXT:    amadd_db.w $a0, $a1, $a0
+; LA64-NEXT:    amadd_db.w $a2, $a1, $a0
+; LA64-NEXT:    move $a0, $a2
 ; LA64-NEXT:    ret
   %1 = atomicrmw add ptr %a, i32 %b acquire
   ret i32 %1
@@ -280,7 +283,8 @@
 ;
 ; LA64-LABEL: atomicrmw_add_i64_acquire:
 ; LA64:       # %bb.0:
-; LA64-NEXT:    amadd_db.d $a0, $a1, $a0
+; LA64-NEXT:    amadd_db.d $a2, $a1, $a0
+; LA64-NEXT:    move $a0, $a2
 ; LA64-NEXT:    ret
   %1 = atomicrmw add ptr %a, i64 %b acquire
   ret i64 %1
@@ -403,8 +407,9 @@
 ;
 ; LA64-LABEL: atomicrmw_sub_i32_acquire:
 ; LA64:       # %bb.0:
-; LA64-NEXT:    sub.w $a1, $zero, $a1
-; LA64-NEXT:    amadd_db.w $a0, $a1, $a0
+; LA64-NEXT:    sub.w $a2, $zero, $a1
+; LA64-NEXT:    amadd_db.w $a1, $a2, $a0
+; LA64-NEXT:    move $a0, $a1
 ; LA64-NEXT:    ret
   %1 = atomicrmw sub ptr %a, i32 %b acquire
   ret i32 %1
@@ -423,8 +428,9 @@
 ;
 ; LA64-LABEL: atomicrmw_sub_i64_acquire:
 ; LA64:       # %bb.0:
-; LA64-NEXT:    sub.d $a1, $zero, $a1
-; LA64-NEXT:    amadd_db.d $a0, $a1, $a0
+; LA64-NEXT:    sub.d $a2, $zero, $a1
+; LA64-NEXT:    amadd_db.d $a1, $a2, $a0
+; LA64-NEXT:    move $a0, $a1
 ; LA64-NEXT:    ret
   %1 = atomicrmw sub ptr %a, i64 %b acquire
   ret i64 %1
@@ -624,8 +630,8 @@
 ; LA64-NEXT:    orn $a1, $a1, $a3
 ; LA64-NEXT:    addi.w $a3, $zero, -4
 ; LA64-NEXT:    and $a0, $a0, $a3
-; LA64-NEXT:    amand_db.w $a0, $a1, $a0
-; LA64-NEXT:    srl.w $a0, $a0, $a2
+; LA64-NEXT:    amand_db.w $a3, $a1, $a0
+; LA64-NEXT:    srl.w $a0, $a3, $a2
 ; LA64-NEXT:    ret
   %1 = atomicrmw and ptr %a, i8 %b acquire
   ret i8 %1
@@ -664,8 +670,8 @@
 ; LA64-NEXT:    orn $a1, $a1, $a2
 ; LA64-NEXT:    addi.w $a2, $zero, -4
 ; LA64-NEXT:    and $a0, $a0, $a2
-; LA64-NEXT:    amand_db.w $a0, $a1, $a0
-; LA64-NEXT:    srl.w $a0, $a0, $a3
+; LA64-NEXT:    amand_db.w $a2, $a1, $a0
+; LA64-NEXT:    srl.w $a0, $a2, $a3
 ; LA64-NEXT:    ret
   %1 = atomicrmw and ptr %a, i16 %b acquire
   ret i16 %1
@@ -686,7 +692,8 @@
 ;
 ; LA64-LABEL: atomicrmw_and_i32_acquire:
 ; LA64:       # %bb.0:
-; LA64-NEXT:    amand_db.w $a0, $a1, $a0
+; LA64-NEXT:    amand_db.w $a2, $a1, $a0
+; LA64-NEXT:    move $a0, $a2
 ; LA64-NEXT:    ret
   %1 = atomicrmw and ptr %a, i32 %b acquire
   ret i32 %1
@@ -705,7 +712,8 @@
 ;
 ; LA64-LABEL: atomicrmw_and_i64_acquire:
 ; LA64:       # %bb.0:
-; LA64-NEXT:    amand_db.d $a0, $a1, $a0
+; LA64-NEXT:    amand_db.d $a2, $a1, $a0
+; LA64-NEXT:    move $a0, $a2
 ; LA64-NEXT:    ret
   %1 = atomicrmw and ptr %a, i64 %b acquire
   ret i64 %1
@@ -736,8 +744,8 @@
 ; LA64-NEXT:    slli.d $a0, $a0, 3
 ; LA64-NEXT:    andi $a1, $a1, 255
 ; LA64-NEXT:    sll.w $a1, $a1, $a0
-; LA64-NEXT:    amor_db.w $a1, $a1, $a2
-; LA64-NEXT:    srl.w $a0, $a1, $a0
+; LA64-NEXT:    amor_db.w $a3, $a1, $a2
+; LA64-NEXT:    srl.w $a0, $a3, $a0
 ; LA64-NEXT:    ret
   %1 = atomicrmw or ptr %a, i8 %b acquire
   ret i8 %1
@@ -768,8 +776,8 @@
 ; LA64-NEXT:    slli.d $a0, $a0, 3
 ; LA64-NEXT:    bstrpick.d $a1, $a1, 15, 0
 ; LA64-NEXT:    sll.w $a1, $a1, $a0
-; LA64-NEXT:    amor_db.w $a1, $a1, $a2
-; LA64-NEXT:    srl.w $a0, $a1, $a0
+; LA64-NEXT:    amor_db.w $a3, $a1, $a2
+; LA64-NEXT:    srl.w $a0, $a3, $a0
 ; LA64-NEXT:    ret
   %1 = atomicrmw or ptr %a, i16 %b acquire
   ret i16 %1
@@ -790,7 +798,8 @@
 ;
 ; LA64-LABEL: atomicrmw_or_i32_acquire:
 ; LA64:       # %bb.0:
-; LA64-NEXT:    amor_db.w $a0, $a1, $a0
+; LA64-NEXT:    amor_db.w $a2, $a1, $a0
+; LA64-NEXT:    move $a0, $a2
 ; LA64-NEXT:    ret
   %1 = atomicrmw or ptr %a, i32 %b acquire
   ret i32 %1
@@ -809,7 +818,8 @@
 ;
 ; LA64-LABEL: atomicrmw_or_i64_acquire:
 ; LA64:       # %bb.0:
-; LA64-NEXT:    amor_db.d $a0, $a1, $a0
+; LA64-NEXT:    amor_db.d $a2, $a1, $a0
+; LA64-NEXT:    move $a0, $a2
 ; LA64-NEXT:    ret
   %1 = atomicrmw or ptr %a, i64 %b acquire
   ret i64 %1
@@ -840,8 +850,8 @@
 ; LA64-NEXT:    slli.d $a0, $a0, 3
 ; LA64-NEXT:    andi $a1, $a1, 255
 ; LA64-NEXT:    sll.w $a1, $a1, $a0
-; LA64-NEXT:    amxor_db.w $a1, $a1, $a2
-; LA64-NEXT:    srl.w $a0, $a1, $a0
+; LA64-NEXT:    amxor_db.w $a3, $a1, $a2
+; LA64-NEXT:    srl.w $a0, $a3, $a0
 ; LA64-NEXT:    ret
   %1 = atomicrmw xor ptr %a, i8 %b acquire
   ret i8 %1
@@ -872,8 +882,8 @@
 ; LA64-NEXT:    slli.d $a0, $a0, 3
 ; LA64-NEXT:    bstrpick.d $a1, $a1, 15, 0
 ; LA64-NEXT:    sll.w $a1, $a1, $a0
-; LA64-NEXT:    amxor_db.w $a1, $a1, $a2
-; LA64-NEXT:    srl.w $a0, $a1, $a0
+; LA64-NEXT:    amxor_db.w $a3, $a1, $a2
+; LA64-NEXT:    srl.w $a0, $a3, $a0
 ; LA64-NEXT:    ret
   %1 = atomicrmw xor ptr %a, i16 %b acquire
   ret i16 %1
@@ -894,7 +904,8 @@
 ;
 ; LA64-LABEL: atomicrmw_xor_i32_acquire:
 ; LA64:       # %bb.0:
-; LA64-NEXT:    amxor_db.w $a0, $a1, $a0
+; LA64-NEXT:    amxor_db.w $a2, $a1, $a0
+; LA64-NEXT:    move $a0, $a2
 ; LA64-NEXT:    ret
   %1 = atomicrmw xor ptr %a, i32 %b acquire
   ret i32 %1
@@ -913,7 +924,8 @@
 ;
 ; LA64-LABEL: atomicrmw_xor_i64_acquire:
 ; LA64:       # %bb.0:
-; LA64-NEXT:    amxor_db.d $a0, $a1, $a0
+; LA64-NEXT:    amxor_db.d $a2, $a1, $a0
+; LA64-NEXT:    move $a0, $a2
 ; LA64-NEXT:    ret
   %1 = atomicrmw xor ptr %a, i64 %b acquire
   ret i64 %1