From: Szabolcs Nagy <szabolcs.nagy@arm.com>
The Guarded Control Stack instructions can be present even if the
hardware does not support the extension (runtime checked feature),
so the asm code should be backward compatible with old assemblers.
---
sysdeps/aarch64/sysdep.h | 7 +++++++
1 file changed, 7 insertions(+)
@@ -74,6 +74,13 @@ strip_pac (void *p)
#define PACIASP hint 25
#define AUTIASP hint 29
+/* Guarded Control Stack support. */
+#define CHKFEAT_X16 hint 40
+#define MRS_GCSPR(x) mrs x, s3_3_c2_c5_1
+#define GCSPOPM(x) sysl x, #3, c7, c7, #1
+#define GCSSS1(x) sys #3, c7, c7, #2, x
+#define GCSSS2(x) sysl x, #3, c7, c7, #3
+
/* GNU_PROPERTY_AARCH64_* macros from elf.h for use in asm code. */
#define FEATURE_1_AND 0xc0000000
#define FEATURE_1_BTI 1