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//@ 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
}
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