| //@ revisions: INT32 INT16 |
| //@ compile-flags: -O |
| //@ [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 |
| } |
