Add ifunc support for aarch64.

	* sysdeps/aarch64/dl-machine.h: Include cpu-features.c.
	(DL_PLATFORM_INIT): New define.
	(dl_platform_init): New function.
	* sysdeps/aarch64/ldsodefs.h: Include cpu-features.h.
	* sysdeps/unix/sysv/linux/aarch64/cpu-features.c: New file.
	* sysdeps/unix/sysv/linux/aarch64/cpu-features.h: Likewise.
	* sysdeps/unix/sysv/linux/aarch64/dl-procinfo.c: Likewise.
	* sysdeps/unix/sysv/linux/aarch64/libc-start.c: Likewise.

1 files changed, 35 insertions, 0 deletions

diff --git a/sysdeps/unix/sysv/linux/aarch64/cpu-features.c b/sysdeps/unix/sysv/linux/aarch64/cpu-features.c
new file mode 100644
index 0000000000..702506249d
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/aarch64/cpu-features.c
@@ -0,0 +1,35 @@
+/* Initialize CPU feature data.  AArch64 version.
+   This file is part of the GNU C Library.
+   Copyright (C) 2017 Free Software Foundation, Inc.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <cpu-features.h>
+#include <sys/auxv.h>
+
+static inline void
+init_cpu_features (struct cpu_features *cpu_features)
+{
+  if (GLRO(dl_hwcap) & HWCAP_CPUID)
+    {
+      register uint64_t id = 0;
+      asm volatile ("mrs %0, midr_el1" : "=r"(id));
+      cpu_features->midr_el1 = id;
+    }
+  else
+    {
+      cpu_features->midr_el1 = 0;
+    }
+}