compiler-rt: Use FreeBSD's elf_aux_info to detect AArch64 HW features
Using the out-of-line LSE atomics helpers for AArch64 on FreeBSD also
requires adding support for initializing __aarch64_have_lse_atomics
correctly. On Linux this is done with getauxval(3), on FreeBSD with
elf_aux_info(3), which has a slightly different interface.
Differential Revision: https://reviews.llvm.org/D109330
GitOrigin-RevId: 7dbbb5d3a46e1526cfa126ae02a5856d7ce0fda9
diff --git a/lib/builtins/cpu_model.c b/lib/builtins/cpu_model.c
index b8d807e..53e2d89 100644
--- a/lib/builtins/cpu_model.c
+++ b/lib/builtins/cpu_model.c
@@ -799,8 +799,14 @@
#define HWCAP_ATOMICS (1 << 8)
#endif
static void CONSTRUCTOR_ATTRIBUTE init_have_lse_atomics(void) {
+#if defined(__FreeBSD__)
+ unsigned long hwcap;
+ int result = elf_aux_info(AT_HWCAP, &hwcap, sizeof hwcap);
+ __aarch64_have_lse_atomics = result == 0 && (hwcap & HWCAP_ATOMICS) != 0;
+#else
unsigned long hwcap = getauxval(AT_HWCAP);
__aarch64_have_lse_atomics = (hwcap & HWCAP_ATOMICS) != 0;
+#endif
}
#endif // defined(__has_include)
#endif // __has_include(<sys/auxv.h>)
