| //@ revisions: INT32 INT16 | |
| //@ compile-flags: -Copt-level=3 | |
| //@ [INT32] ignore-16bit | |
| //@ [INT16] only-16bit | |
| #![crate_type = "lib"] | |
| #![feature(core_intrinsics)] | |
| use std::intrinsics::compare_bytes; | |
| #[no_mangle] | |
| // CHECK-LABEL: @bytes_cmp( | |
| pub unsafe fn bytes_cmp(a: *const u8, b: *const u8, n: usize) -> i32 { | |
| // INT32: %[[TEMP:.+]] = tail call i32 @memcmp(ptr %a, ptr %b, {{i32|i64}} %n) | |
| // INT32-NOT: sext | |
| // INT32: ret i32 %[[TEMP]] | |
| // INT16: %[[TEMP1:.+]] = tail call i16 @memcmp(ptr %a, ptr %b, i16 %n) | |
| // INT16: %[[TEMP2:.+]] = sext i16 %[[TEMP1]] to i32 | |
| // INT16: ret i32 %[[TEMP2]] | |
| compare_bytes(a, b, n) | |
| } | |
| // Ensure that, even though there's an `sext` emitted by the intrinsic, | |
| // that doesn't end up pessiming checks against zero. | |
| #[no_mangle] | |
| // CHECK-LABEL: @bytes_eq( | |
| pub unsafe fn bytes_eq(a: *const u8, b: *const u8, n: usize) -> bool { | |
| // CHECK: call {{.+}} @{{bcmp|memcmp}}(ptr %a, ptr %b, {{i16|i32|i64}} %n) | |
| // CHECK-NOT: sext | |
| // INT32: icmp eq i32 | |
| // INT16: icmp eq i16 | |
| compare_bytes(a, b, n) == 0_i32 | |
| } |