xref: /xnu-8792.61.2/tests/x18_legacy.c (revision 42e220869062b56f8d7d0726fd4c88954f87902c)
1*42e22086SApple OSS Distributions /*
2*42e22086SApple OSS Distributions  * Copyright (c) 2019-2022 Apple Inc. All rights reserved.
3*42e22086SApple OSS Distributions  *
4*42e22086SApple OSS Distributions  * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
5*42e22086SApple OSS Distributions  *
6*42e22086SApple OSS Distributions  * This file contains Original Code and/or Modifications of Original Code
7*42e22086SApple OSS Distributions  * as defined in and that are subject to the Apple Public Source License
8*42e22086SApple OSS Distributions  * Version 2.0 (the 'License'). You may not use this file except in
9*42e22086SApple OSS Distributions  * compliance with the License. The rights granted to you under the License
10*42e22086SApple OSS Distributions  * may not be used to create, or enable the creation or redistribution of,
11*42e22086SApple OSS Distributions  * unlawful or unlicensed copies of an Apple operating system, or to
12*42e22086SApple OSS Distributions  * circumvent, violate, or enable the circumvention or violation of, any
13*42e22086SApple OSS Distributions  * terms of an Apple operating system software license agreement.
14*42e22086SApple OSS Distributions  *
15*42e22086SApple OSS Distributions  * Please obtain a copy of the License at
16*42e22086SApple OSS Distributions  * http://www.opensource.apple.com/apsl/ and read it before using this file.
17*42e22086SApple OSS Distributions  *
18*42e22086SApple OSS Distributions  * The Original Code and all software distributed under the License are
19*42e22086SApple OSS Distributions  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
20*42e22086SApple OSS Distributions  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
21*42e22086SApple OSS Distributions  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
22*42e22086SApple OSS Distributions  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
23*42e22086SApple OSS Distributions  * Please see the License for the specific language governing rights and
24*42e22086SApple OSS Distributions  * limitations under the License.
25*42e22086SApple OSS Distributions  *
26*42e22086SApple OSS Distributions  * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
27*42e22086SApple OSS Distributions  */
28*42e22086SApple OSS Distributions 
29*42e22086SApple OSS Distributions #include <darwintest.h>
30*42e22086SApple OSS Distributions #include <pthread.h>
31*42e22086SApple OSS Distributions #include <sys/types.h>
32*42e22086SApple OSS Distributions #include <sys/sysctl.h>
33*42e22086SApple OSS Distributions 
34*42e22086SApple OSS Distributions T_GLOBAL_META(
35*42e22086SApple OSS Distributions 	T_META_NAMESPACE("xnu.arm"),
36*42e22086SApple OSS Distributions 	T_META_RADAR_COMPONENT_NAME("xnu"),
37*42e22086SApple OSS Distributions 	T_META_RADAR_COMPONENT_VERSION("arm"),
38*42e22086SApple OSS Distributions 	T_META_OWNER("joster"),
39*42e22086SApple OSS Distributions 	T_META_REQUIRES_SYSCTL_EQ("hw.optional.arm_kernel_protect", 0), // will crash on arm_kernel_protect devices
40*42e22086SApple OSS Distributions 	T_META_RUN_CONCURRENTLY(true));
41*42e22086SApple OSS Distributions 
42*42e22086SApple OSS Distributions T_DECL(x18_legacy,
43*42e22086SApple OSS Distributions     "Test that x18 is preserved on hardware that supports it, if linked for an old macOS version.")
44*42e22086SApple OSS Distributions {
45*42e22086SApple OSS Distributions #ifndef __arm64__
46*42e22086SApple OSS Distributions 	T_SKIP("Running on non-arm64 target, skipping...");
47*42e22086SApple OSS Distributions #else
48*42e22086SApple OSS Distributions 	uint64_t x18_val;
49*42e22086SApple OSS Distributions 	for (uint64_t i = 0xFEEDB0B000000000ULL; i < 0xFEEDB0B000000000ULL + 10000; ++i) {
50*42e22086SApple OSS Distributions 		asm volatile ("mov x18, %0" : : "r"(i));
51*42e22086SApple OSS Distributions 		sched_yield();
52*42e22086SApple OSS Distributions 		asm volatile ("mov %0, x18" : "=r"(x18_val));
53*42e22086SApple OSS Distributions 		T_QUIET; T_ASSERT_EQ(x18_val, i, "check that x18 reads back correctly after yield");
54*42e22086SApple OSS Distributions 	}
55*42e22086SApple OSS Distributions #endif
56*42e22086SApple OSS Distributions }
57