diff --git a/llvm/test/Transforms/InstCombine/cheri-memcpy-64bit-cap.ll b/llvm/test/Transforms/InstCombine/cheri-memcpy-64bit-cap.ll
new file mode 100644
index 000000000000..da3ad71c5c60
--- /dev/null
+++ b/llvm/test/Transforms/InstCombine/cheri-memcpy-64bit-cap.ll
@@ -0,0 +1,77 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
+; RUN: opt < %s -instcombine -S | FileCheck %s
+target datalayout = "e-m:e-pf200:64:64:64:32-p:32:32-i64:64-n32-S128-A200-P200-G200"
+
+;; memcpy has capability size and alignment, and may copy a capability
+
+define ptr addrspace(200) @test_memcpy_cap(ptr addrspace(200) %d, ptr addrspace(200) %s) {
+; CHECK-LABEL: @test_memcpy_cap(
+; CHECK-NEXT:    [[TMP1:%.*]] = load i64, ptr addrspace(200) [[S:%.*]], align 8
+; CHECK-NEXT:    store i64 [[TMP1]], ptr addrspace(200) [[D:%.*]], align 8
+; CHECK-NEXT:    ret ptr addrspace(200) [[D]]
+;
+  call void @llvm.memcpy.p200.p200.i32(ptr addrspace(200) align 8 %d, ptr addrspace(200) align 8 %s, i32 8, i1 false) must_preserve_cheri_tags
+  ret ptr addrspace(200) %d
+}
+
+;; memcpy may contain a capability, but alignment is not known
+
+define ptr addrspace(200) @test_memcpy8_align_unknown(ptr addrspace(200) %d, ptr addrspace(200) %s) {
+; CHECK-LABEL: @test_memcpy8_align_unknown(
+; CHECK-NEXT:    [[TMP1:%.*]] = load i64, ptr addrspace(200) [[S:%.*]], align 1
+; CHECK-NEXT:    store i64 [[TMP1]], ptr addrspace(200) [[D:%.*]], align 1
+; CHECK-NEXT:    ret ptr addrspace(200) [[D]]
+;
+  call void @llvm.memcpy.p200.p200.i32(ptr addrspace(200) %d, ptr addrspace(200) %s, i32 8, i1 false) must_preserve_cheri_tags
+  ret ptr addrspace(200) %d
+}
+
+;; memcpy may contain a capability, but alignment may not be sufficient for capability load/store
+
+define ptr addrspace(200) @test_memcpy8_align_4(ptr addrspace(200) %d, ptr addrspace(200) %s) {
+; CHECK-LABEL: @test_memcpy8_align_4(
+; CHECK-NEXT:    [[TMP1:%.*]] = load i64, ptr addrspace(200) [[S:%.*]], align 4
+; CHECK-NEXT:    store i64 [[TMP1]], ptr addrspace(200) [[D:%.*]], align 4
+; CHECK-NEXT:    ret ptr addrspace(200) [[D]]
+;
+  call void @llvm.memcpy.p200.p200.i32(ptr addrspace(200) align 4 %d, ptr addrspace(200) align 4 %s, i32 8, i1 false) must_preserve_cheri_tags
+  ret ptr addrspace(200) %d
+}
+
+;; memcpy does not copy capabilities, so can be transformed to regular load/store
+
+define ptr addrspace(200) @test_memcpy8_nocap(ptr addrspace(200) %d, ptr addrspace(200) %s) {
+; CHECK-LABEL: @test_memcpy8_nocap(
+; CHECK-NEXT:    [[TMP1:%.*]] = load i64, ptr addrspace(200) [[S:%.*]], align 8
+; CHECK-NEXT:    store i64 [[TMP1]], ptr addrspace(200) [[D:%.*]], align 8
+; CHECK-NEXT:    ret ptr addrspace(200) [[D]]
+;
+  call void @llvm.memcpy.p200.p200.i32(ptr addrspace(200) align 8 %d, ptr addrspace(200) align 8 %s, i32 8, i1 false) no_preserve_cheri_tags
+  ret ptr addrspace(200) %d
+}
+
+;; memcpy has unknown alignment but does not copy capabilities, so can be transformed to regular load/store
+
+define ptr addrspace(200) @test_memcpy8_nocap_align_unknown(ptr addrspace(200) %d, ptr addrspace(200) %s) {
+; CHECK-LABEL: @test_memcpy8_nocap_align_unknown(
+; CHECK-NEXT:    [[TMP1:%.*]] = load i64, ptr addrspace(200) [[S:%.*]], align 1
+; CHECK-NEXT:    store i64 [[TMP1]], ptr addrspace(200) [[D:%.*]], align 1
+; CHECK-NEXT:    ret ptr addrspace(200) [[D]]
+;
+  call void @llvm.memcpy.p200.p200.i32(ptr addrspace(200) %d, ptr addrspace(200) %s, i32 8, i1 false) no_preserve_cheri_tags
+  ret ptr addrspace(200) %d
+}
+
+;; memcpy has align 4 and does not copy capabilities, so can be transformed to regular load/store
+
+define ptr addrspace(200) @test_memcpy8_nocap_align_4(ptr addrspace(200) %d, ptr addrspace(200) %s) {
+; CHECK-LABEL: @test_memcpy8_nocap_align_4(
+; CHECK-NEXT:    [[TMP1:%.*]] = load i64, ptr addrspace(200) [[S:%.*]], align 4
+; CHECK-NEXT:    store i64 [[TMP1]], ptr addrspace(200) [[D:%.*]], align 4
+; CHECK-NEXT:    ret ptr addrspace(200) [[D]]
+;
+  call void @llvm.memcpy.p200.p200.i32(ptr addrspace(200) align 4 %d, ptr addrspace(200) align 4 %s, i32 8, i1 false) no_preserve_cheri_tags
+  ret ptr addrspace(200) %d
+}
+
+declare void @llvm.memcpy.p200.p200.i32(ptr addrspace(200), ptr addrspace(200), i32, i1 immarg)