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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
commit2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch)
tree848558de17fb3008cdf4d861b01ac7781903ce39 /tools/testing/selftests/arm64/bti
parentInitial commit. (diff)
downloadlinux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz
linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip
Adding upstream version 6.1.76.upstream/6.1.76
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'tools/testing/selftests/arm64/bti')
-rw-r--r--tools/testing/selftests/arm64/bti/.gitignore2
-rw-r--r--tools/testing/selftests/arm64/bti/Makefile61
-rw-r--r--tools/testing/selftests/arm64/bti/assembler.h80
-rw-r--r--tools/testing/selftests/arm64/bti/btitest.h23
-rw-r--r--tools/testing/selftests/arm64/bti/compiler.h21
-rw-r--r--tools/testing/selftests/arm64/bti/gen/.gitignore2
-rw-r--r--tools/testing/selftests/arm64/bti/signal.c37
-rw-r--r--tools/testing/selftests/arm64/bti/signal.h21
-rw-r--r--tools/testing/selftests/arm64/bti/start.S14
-rw-r--r--tools/testing/selftests/arm64/bti/syscall.S23
-rw-r--r--tools/testing/selftests/arm64/bti/system.c22
-rw-r--r--tools/testing/selftests/arm64/bti/system.h28
-rw-r--r--tools/testing/selftests/arm64/bti/test.c235
-rw-r--r--tools/testing/selftests/arm64/bti/teststubs.S39
-rw-r--r--tools/testing/selftests/arm64/bti/trampoline.S29
15 files changed, 637 insertions, 0 deletions
diff --git a/tools/testing/selftests/arm64/bti/.gitignore b/tools/testing/selftests/arm64/bti/.gitignore
new file mode 100644
index 000000000..73869faba
--- /dev/null
+++ b/tools/testing/selftests/arm64/bti/.gitignore
@@ -0,0 +1,2 @@
+btitest
+nobtitest
diff --git a/tools/testing/selftests/arm64/bti/Makefile b/tools/testing/selftests/arm64/bti/Makefile
new file mode 100644
index 000000000..ccdac414a
--- /dev/null
+++ b/tools/testing/selftests/arm64/bti/Makefile
@@ -0,0 +1,61 @@
+# SPDX-License-Identifier: GPL-2.0
+
+TEST_GEN_PROGS := btitest nobtitest
+
+PROGS := $(patsubst %,gen/%,$(TEST_GEN_PROGS))
+
+# These tests are built as freestanding binaries since otherwise BTI
+# support in ld.so is required which is not currently widespread; when
+# it is available it will still be useful to test this separately as the
+# cases for statically linked and dynamically lined binaries are
+# slightly different.
+
+CFLAGS_NOBTI = -mbranch-protection=none -DBTI=0
+CFLAGS_BTI = -mbranch-protection=standard -DBTI=1
+
+CFLAGS_COMMON = -ffreestanding -Wall -Wextra $(CFLAGS)
+
+BTI_CC_COMMAND = $(CC) $(CFLAGS_BTI) $(CFLAGS_COMMON) -c -o $@ $<
+NOBTI_CC_COMMAND = $(CC) $(CFLAGS_NOBTI) $(CFLAGS_COMMON) -c -o $@ $<
+
+%-bti.o: %.c
+ $(BTI_CC_COMMAND)
+
+%-bti.o: %.S
+ $(BTI_CC_COMMAND)
+
+%-nobti.o: %.c
+ $(NOBTI_CC_COMMAND)
+
+%-nobti.o: %.S
+ $(NOBTI_CC_COMMAND)
+
+BTI_OBJS = \
+ test-bti.o \
+ signal-bti.o \
+ start-bti.o \
+ syscall-bti.o \
+ system-bti.o \
+ teststubs-bti.o \
+ trampoline-bti.o
+gen/btitest: $(BTI_OBJS)
+ $(CC) $(CFLAGS_BTI) $(CFLAGS_COMMON) -nostdlib -static -o $@ $^
+
+NOBTI_OBJS = \
+ test-nobti.o \
+ signal-nobti.o \
+ start-nobti.o \
+ syscall-nobti.o \
+ system-nobti.o \
+ teststubs-nobti.o \
+ trampoline-nobti.o
+gen/nobtitest: $(NOBTI_OBJS)
+ $(CC) $(CFLAGS_BTI) $(CFLAGS_COMMON) -nostdlib -static -o $@ $^
+
+# Including KSFT lib.mk here will also mangle the TEST_GEN_PROGS list
+# to account for any OUTPUT target-dirs optionally provided by
+# the toplevel makefile
+include ../../lib.mk
+
+$(TEST_GEN_PROGS): $(PROGS)
+ cp $(PROGS) $(OUTPUT)/
diff --git a/tools/testing/selftests/arm64/bti/assembler.h b/tools/testing/selftests/arm64/bti/assembler.h
new file mode 100644
index 000000000..04e7b7288
--- /dev/null
+++ b/tools/testing/selftests/arm64/bti/assembler.h
@@ -0,0 +1,80 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2019 Arm Limited
+ * Original author: Dave Martin <Dave.Martin@arm.com>
+ */
+
+#ifndef ASSEMBLER_H
+#define ASSEMBLER_H
+
+#define NT_GNU_PROPERTY_TYPE_0 5
+#define GNU_PROPERTY_AARCH64_FEATURE_1_AND 0xc0000000
+
+/* Bits for GNU_PROPERTY_AARCH64_FEATURE_1_BTI */
+#define GNU_PROPERTY_AARCH64_FEATURE_1_BTI (1U << 0)
+#define GNU_PROPERTY_AARCH64_FEATURE_1_PAC (1U << 1)
+
+
+.macro startfn name:req
+ .globl \name
+\name:
+ .macro endfn
+ .size \name, . - \name
+ .type \name, @function
+ .purgem endfn
+ .endm
+.endm
+
+.macro emit_aarch64_feature_1_and
+ .pushsection .note.gnu.property, "a"
+ .align 3
+ .long 2f - 1f
+ .long 6f - 3f
+ .long NT_GNU_PROPERTY_TYPE_0
+1: .string "GNU"
+2:
+ .align 3
+3: .long GNU_PROPERTY_AARCH64_FEATURE_1_AND
+ .long 5f - 4f
+4:
+#if BTI
+ .long GNU_PROPERTY_AARCH64_FEATURE_1_PAC | \
+ GNU_PROPERTY_AARCH64_FEATURE_1_BTI
+#else
+ .long 0
+#endif
+5:
+ .align 3
+6:
+ .popsection
+.endm
+
+.macro paciasp
+ hint 0x19
+.endm
+
+.macro autiasp
+ hint 0x1d
+.endm
+
+.macro __bti_
+ hint 0x20
+.endm
+
+.macro __bti_c
+ hint 0x22
+.endm
+
+.macro __bti_j
+ hint 0x24
+.endm
+
+.macro __bti_jc
+ hint 0x26
+.endm
+
+.macro bti what=
+ __bti_\what
+.endm
+
+#endif /* ! ASSEMBLER_H */
diff --git a/tools/testing/selftests/arm64/bti/btitest.h b/tools/testing/selftests/arm64/bti/btitest.h
new file mode 100644
index 000000000..2aff9b103
--- /dev/null
+++ b/tools/testing/selftests/arm64/bti/btitest.h
@@ -0,0 +1,23 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2019 Arm Limited
+ * Original author: Dave Martin <Dave.Martin@arm.com>
+ */
+
+#ifndef BTITEST_H
+#define BTITEST_H
+
+/* Trampolines for calling the test stubs: */
+void call_using_br_x0(void (*)(void));
+void call_using_br_x16(void (*)(void));
+void call_using_blr(void (*)(void));
+
+/* Test stubs: */
+void nohint_func(void);
+void bti_none_func(void);
+void bti_c_func(void);
+void bti_j_func(void);
+void bti_jc_func(void);
+void paciasp_func(void);
+
+#endif /* !BTITEST_H */
diff --git a/tools/testing/selftests/arm64/bti/compiler.h b/tools/testing/selftests/arm64/bti/compiler.h
new file mode 100644
index 000000000..ebb6204f4
--- /dev/null
+++ b/tools/testing/selftests/arm64/bti/compiler.h
@@ -0,0 +1,21 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2019 Arm Limited
+ * Original author: Dave Martin <Dave.Martin@arm.com>
+ */
+
+#ifndef COMPILER_H
+#define COMPILER_H
+
+#define __always_unused __attribute__((__unused__))
+#define __noreturn __attribute__((__noreturn__))
+#define __unreachable() __builtin_unreachable()
+
+/* curse(e) has value e, but the compiler cannot assume so */
+#define curse(e) ({ \
+ __typeof__(e) __curse_e = (e); \
+ asm ("" : "+r" (__curse_e)); \
+ __curse_e; \
+})
+
+#endif /* ! COMPILER_H */
diff --git a/tools/testing/selftests/arm64/bti/gen/.gitignore b/tools/testing/selftests/arm64/bti/gen/.gitignore
new file mode 100644
index 000000000..73869faba
--- /dev/null
+++ b/tools/testing/selftests/arm64/bti/gen/.gitignore
@@ -0,0 +1,2 @@
+btitest
+nobtitest
diff --git a/tools/testing/selftests/arm64/bti/signal.c b/tools/testing/selftests/arm64/bti/signal.c
new file mode 100644
index 000000000..f3fd29b91
--- /dev/null
+++ b/tools/testing/selftests/arm64/bti/signal.c
@@ -0,0 +1,37 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2019 Arm Limited
+ * Original author: Dave Martin <Dave.Martin@arm.com>
+ */
+
+#include "system.h"
+#include "signal.h"
+
+int sigemptyset(sigset_t *s)
+{
+ unsigned int i;
+
+ for (i = 0; i < _NSIG_WORDS; ++i)
+ s->sig[i] = 0;
+
+ return 0;
+}
+
+int sigaddset(sigset_t *s, int n)
+{
+ if (n < 1 || n > _NSIG)
+ return -EINVAL;
+
+ s->sig[(n - 1) / _NSIG_BPW] |= 1UL << (n - 1) % _NSIG_BPW;
+ return 0;
+}
+
+int sigaction(int n, struct sigaction *sa, const struct sigaction *old)
+{
+ return syscall(__NR_rt_sigaction, n, sa, old, sizeof(sa->sa_mask));
+}
+
+int sigprocmask(int how, const sigset_t *mask, sigset_t *old)
+{
+ return syscall(__NR_rt_sigprocmask, how, mask, old, sizeof(*mask));
+}
diff --git a/tools/testing/selftests/arm64/bti/signal.h b/tools/testing/selftests/arm64/bti/signal.h
new file mode 100644
index 000000000..103457dc8
--- /dev/null
+++ b/tools/testing/selftests/arm64/bti/signal.h
@@ -0,0 +1,21 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2019 Arm Limited
+ * Original author: Dave Martin <Dave.Martin@arm.com>
+ */
+
+#ifndef SIGNAL_H
+#define SIGNAL_H
+
+#include <linux/signal.h>
+
+#include "system.h"
+
+typedef __sighandler_t sighandler_t;
+
+int sigemptyset(sigset_t *s);
+int sigaddset(sigset_t *s, int n);
+int sigaction(int n, struct sigaction *sa, const struct sigaction *old);
+int sigprocmask(int how, const sigset_t *mask, sigset_t *old);
+
+#endif /* ! SIGNAL_H */
diff --git a/tools/testing/selftests/arm64/bti/start.S b/tools/testing/selftests/arm64/bti/start.S
new file mode 100644
index 000000000..831f952e0
--- /dev/null
+++ b/tools/testing/selftests/arm64/bti/start.S
@@ -0,0 +1,14 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2019 Arm Limited
+ * Original author: Dave Martin <Dave.Martin@arm.com>
+ */
+
+#include "assembler.h"
+
+startfn _start
+ mov x0, sp
+ b start
+endfn
+
+emit_aarch64_feature_1_and
diff --git a/tools/testing/selftests/arm64/bti/syscall.S b/tools/testing/selftests/arm64/bti/syscall.S
new file mode 100644
index 000000000..8dde8b6f3
--- /dev/null
+++ b/tools/testing/selftests/arm64/bti/syscall.S
@@ -0,0 +1,23 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2019 Arm Limited
+ * Original author: Dave Martin <Dave.Martin@arm.com>
+ */
+
+#include "assembler.h"
+
+startfn syscall
+ bti c
+ mov w8, w0
+ mov x0, x1
+ mov x1, x2
+ mov x2, x3
+ mov x3, x4
+ mov x4, x5
+ mov x5, x6
+ mov x6, x7
+ svc #0
+ ret
+endfn
+
+emit_aarch64_feature_1_and
diff --git a/tools/testing/selftests/arm64/bti/system.c b/tools/testing/selftests/arm64/bti/system.c
new file mode 100644
index 000000000..6385d8d49
--- /dev/null
+++ b/tools/testing/selftests/arm64/bti/system.c
@@ -0,0 +1,22 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2019 Arm Limited
+ * Original author: Dave Martin <Dave.Martin@arm.com>
+ */
+
+#include "system.h"
+
+#include <asm/unistd.h>
+
+#include "compiler.h"
+
+void __noreturn exit(int n)
+{
+ syscall(__NR_exit, n);
+ __unreachable();
+}
+
+ssize_t write(int fd, const void *buf, size_t size)
+{
+ return syscall(__NR_write, fd, buf, size);
+}
diff --git a/tools/testing/selftests/arm64/bti/system.h b/tools/testing/selftests/arm64/bti/system.h
new file mode 100644
index 000000000..aca118589
--- /dev/null
+++ b/tools/testing/selftests/arm64/bti/system.h
@@ -0,0 +1,28 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2019 Arm Limited
+ * Original author: Dave Martin <Dave.Martin@arm.com>
+ */
+
+#ifndef SYSTEM_H
+#define SYSTEM_H
+
+#include <linux/types.h>
+#include <linux/stddef.h>
+
+typedef __kernel_size_t size_t;
+typedef __kernel_ssize_t ssize_t;
+
+#include <linux/errno.h>
+#include <asm/hwcap.h>
+#include <asm/ptrace.h>
+#include <asm/unistd.h>
+
+#include "compiler.h"
+
+long syscall(int nr, ...);
+
+void __noreturn exit(int n);
+ssize_t write(int fd, const void *buf, size_t size);
+
+#endif /* ! SYSTEM_H */
diff --git a/tools/testing/selftests/arm64/bti/test.c b/tools/testing/selftests/arm64/bti/test.c
new file mode 100644
index 000000000..67b77ab83
--- /dev/null
+++ b/tools/testing/selftests/arm64/bti/test.c
@@ -0,0 +1,235 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2019,2021 Arm Limited
+ * Original author: Dave Martin <Dave.Martin@arm.com>
+ */
+
+#include "system.h"
+
+#include <stddef.h>
+#include <linux/errno.h>
+#include <linux/auxvec.h>
+#include <linux/signal.h>
+#include <asm/sigcontext.h>
+#include <asm/ucontext.h>
+
+typedef struct ucontext ucontext_t;
+
+#include "btitest.h"
+#include "compiler.h"
+#include "signal.h"
+
+#define EXPECTED_TESTS 18
+
+static volatile unsigned int test_num = 1;
+static unsigned int test_passed;
+static unsigned int test_failed;
+static unsigned int test_skipped;
+
+static void fdputs(int fd, const char *str)
+{
+ size_t len = 0;
+ const char *p = str;
+
+ while (*p++)
+ ++len;
+
+ write(fd, str, len);
+}
+
+static void putstr(const char *str)
+{
+ fdputs(1, str);
+}
+
+static void putnum(unsigned int num)
+{
+ char c;
+
+ if (num / 10)
+ putnum(num / 10);
+
+ c = '0' + (num % 10);
+ write(1, &c, 1);
+}
+
+#define puttestname(test_name, trampoline_name) do { \
+ putstr(test_name); \
+ putstr("/"); \
+ putstr(trampoline_name); \
+} while (0)
+
+void print_summary(void)
+{
+ putstr("# Totals: pass:");
+ putnum(test_passed);
+ putstr(" fail:");
+ putnum(test_failed);
+ putstr(" xfail:0 xpass:0 skip:");
+ putnum(test_skipped);
+ putstr(" error:0\n");
+}
+
+static const char *volatile current_test_name;
+static const char *volatile current_trampoline_name;
+static volatile int sigill_expected, sigill_received;
+
+static void handler(int n, siginfo_t *si __always_unused,
+ void *uc_ __always_unused)
+{
+ ucontext_t *uc = uc_;
+
+ putstr("# \t[SIGILL in ");
+ puttestname(current_test_name, current_trampoline_name);
+ putstr(", BTYPE=");
+ write(1, &"00011011"[((uc->uc_mcontext.pstate & PSR_BTYPE_MASK)
+ >> PSR_BTYPE_SHIFT) * 2], 2);
+ if (!sigill_expected) {
+ putstr("]\n");
+ putstr("not ok ");
+ putnum(test_num);
+ putstr(" ");
+ puttestname(current_test_name, current_trampoline_name);
+ putstr("(unexpected SIGILL)\n");
+ print_summary();
+ exit(128 + n);
+ }
+
+ putstr(" (expected)]\n");
+ sigill_received = 1;
+ /* zap BTYPE so that resuming the faulting code will work */
+ uc->uc_mcontext.pstate &= ~PSR_BTYPE_MASK;
+}
+
+static int skip_all;
+
+static void __do_test(void (*trampoline)(void (*)(void)),
+ void (*fn)(void),
+ const char *trampoline_name,
+ const char *name,
+ int expect_sigill)
+{
+ if (skip_all) {
+ test_skipped++;
+ putstr("ok ");
+ putnum(test_num);
+ putstr(" ");
+ puttestname(name, trampoline_name);
+ putstr(" # SKIP\n");
+
+ return;
+ }
+
+ /* Branch Target exceptions should only happen in BTI binaries: */
+ if (!BTI)
+ expect_sigill = 0;
+
+ sigill_expected = expect_sigill;
+ sigill_received = 0;
+ current_test_name = name;
+ current_trampoline_name = trampoline_name;
+
+ trampoline(fn);
+
+ if (expect_sigill && !sigill_received) {
+ putstr("not ok ");
+ test_failed++;
+ } else {
+ putstr("ok ");
+ test_passed++;
+ }
+ putnum(test_num++);
+ putstr(" ");
+ puttestname(name, trampoline_name);
+ putstr("\n");
+}
+
+#define do_test(expect_sigill_br_x0, \
+ expect_sigill_br_x16, \
+ expect_sigill_blr, \
+ name) \
+do { \
+ __do_test(call_using_br_x0, name, "call_using_br_x0", #name, \
+ expect_sigill_br_x0); \
+ __do_test(call_using_br_x16, name, "call_using_br_x16", #name, \
+ expect_sigill_br_x16); \
+ __do_test(call_using_blr, name, "call_using_blr", #name, \
+ expect_sigill_blr); \
+} while (0)
+
+void start(int *argcp)
+{
+ struct sigaction sa;
+ void *const *p;
+ const struct auxv_entry {
+ unsigned long type;
+ unsigned long val;
+ } *auxv;
+ unsigned long hwcap = 0, hwcap2 = 0;
+
+ putstr("TAP version 13\n");
+ putstr("1..");
+ putnum(EXPECTED_TESTS);
+ putstr("\n");
+
+ /* Gross hack for finding AT_HWCAP2 from the initial process stack: */
+ p = (void *const *)argcp + 1 + *argcp + 1; /* start of environment */
+ /* step over environment */
+ while (*p++)
+ ;
+ for (auxv = (const struct auxv_entry *)p; auxv->type != AT_NULL; ++auxv) {
+ switch (auxv->type) {
+ case AT_HWCAP:
+ hwcap = auxv->val;
+ break;
+ case AT_HWCAP2:
+ hwcap2 = auxv->val;
+ break;
+ default:
+ break;
+ }
+ }
+
+ if (hwcap & HWCAP_PACA)
+ putstr("# HWCAP_PACA present\n");
+ else
+ putstr("# HWCAP_PACA not present\n");
+
+ if (hwcap2 & HWCAP2_BTI) {
+ putstr("# HWCAP2_BTI present\n");
+ if (!(hwcap & HWCAP_PACA))
+ putstr("# Bad hardware? Expect problems.\n");
+ } else {
+ putstr("# HWCAP2_BTI not present\n");
+ skip_all = 1;
+ }
+
+ putstr("# Test binary");
+ if (!BTI)
+ putstr(" not");
+ putstr(" built for BTI\n");
+
+ sa.sa_handler = (sighandler_t)(void *)handler;
+ sa.sa_flags = SA_SIGINFO;
+ sigemptyset(&sa.sa_mask);
+ sigaction(SIGILL, &sa, NULL);
+ sigaddset(&sa.sa_mask, SIGILL);
+ sigprocmask(SIG_UNBLOCK, &sa.sa_mask, NULL);
+
+ do_test(1, 1, 1, nohint_func);
+ do_test(1, 1, 1, bti_none_func);
+ do_test(1, 0, 0, bti_c_func);
+ do_test(0, 0, 1, bti_j_func);
+ do_test(0, 0, 0, bti_jc_func);
+ do_test(1, 0, 0, paciasp_func);
+
+ print_summary();
+
+ if (test_num - 1 != EXPECTED_TESTS)
+ putstr("# WARNING - EXPECTED TEST COUNT WRONG\n");
+
+ if (test_failed)
+ exit(1);
+ else
+ exit(0);
+}
diff --git a/tools/testing/selftests/arm64/bti/teststubs.S b/tools/testing/selftests/arm64/bti/teststubs.S
new file mode 100644
index 000000000..b62c8c35f
--- /dev/null
+++ b/tools/testing/selftests/arm64/bti/teststubs.S
@@ -0,0 +1,39 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2019 Arm Limited
+ * Original author: Dave Martin <Dave.Martin@arm.com>
+ */
+
+#include "assembler.h"
+
+startfn bti_none_func
+ bti
+ ret
+endfn
+
+startfn bti_c_func
+ bti c
+ ret
+endfn
+
+startfn bti_j_func
+ bti j
+ ret
+endfn
+
+startfn bti_jc_func
+ bti jc
+ ret
+endfn
+
+startfn paciasp_func
+ paciasp
+ autiasp
+ ret
+endfn
+
+startfn nohint_func
+ ret
+endfn
+
+emit_aarch64_feature_1_and
diff --git a/tools/testing/selftests/arm64/bti/trampoline.S b/tools/testing/selftests/arm64/bti/trampoline.S
new file mode 100644
index 000000000..09beb3f36
--- /dev/null
+++ b/tools/testing/selftests/arm64/bti/trampoline.S
@@ -0,0 +1,29 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2019 Arm Limited
+ * Original author: Dave Martin <Dave.Martin@arm.com>
+ */
+
+#include "assembler.h"
+
+startfn call_using_br_x0
+ bti c
+ br x0
+endfn
+
+startfn call_using_br_x16
+ bti c
+ mov x16, x0
+ br x16
+endfn
+
+startfn call_using_blr
+ paciasp
+ stp x29, x30, [sp, #-16]!
+ blr x0
+ ldp x29, x30, [sp], #16
+ autiasp
+ ret
+endfn
+
+emit_aarch64_feature_1_and