[NFC] Precommit a memcpy test for isOrEquivalentToAdd (#82758)

Author: heiher

llvm/test/CodeGen/LoongArch/intrinsic-memcpy.ll

@@ -0,0 +1,34 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
+; RUN: llc --mtriple=loongarch64 < %s | FileCheck %s
+
+%Box = type [6 x i64]
+
+define void @box(ptr noalias nocapture noundef writeonly sret(%Box) align 16 dereferenceable(48) %b, i64 %i) {
+; CHECK-LABEL: box:
+; CHECK:       # %bb.0:
+; CHECK-NEXT:    addi.d $sp, $sp, -96
+; CHECK-NEXT:    .cfi_def_cfa_offset 96
+; CHECK-NEXT:    slli.d $a2, $a1, 5
+; CHECK-NEXT:    alsl.d $a1, $a1, $a2, 4
+; CHECK-NEXT:    addi.d $a2, $sp, 0
+; CHECK-NEXT:    add.d $a3, $a2, $a1
+; CHECK-NEXT:    ldx.d $a1, $a1, $a2
+; CHECK-NEXT:    st.d $a1, $a0, 0
+; CHECK-NEXT:    ld.d $a1, $a3, 40
+; CHECK-NEXT:    st.d $a1, $a0, 40
+; CHECK-NEXT:    ld.d $a1, $a3, 32
+; CHECK-NEXT:    st.d $a1, $a0, 32
+; CHECK-NEXT:    ld.d $a1, $a3, 24
+; CHECK-NEXT:    st.d $a1, $a0, 24
+; CHECK-NEXT:    ld.d $a1, $a3, 16
+; CHECK-NEXT:    st.d $a1, $a0, 16
+; CHECK-NEXT:    ori $a1, $a3, 8
+; CHECK-NEXT:    ld.d $a1, $a1, 0
+; CHECK-NEXT:    st.d $a1, $a0, 8
+; CHECK-NEXT:    addi.d $sp, $sp, 96
+; CHECK-NEXT:    ret
+  %1 = alloca [2 x %Box], align 16
+  %2 = getelementptr inbounds [2 x %Box], ptr %1, i64 0, i64 %i
+  call void @llvm.memcpy.p0.p0.i64(ptr noundef nonnull align 16 dereferenceable(48) %b, ptr noundef nonnull align 16 dereferenceable(48) %2, i64 48, i1 false)
+  ret void
+}