[AArch64] Only build & test pauth code for LP64

gcc/
	* config/aarch64/aarch64-builtins.c (aarch64_init_builtins): Register
	register pauth builtins for LP64 only.

libgcc/
	* config/aarch64/aarch64-unwind.h: Empty this file on ILP32.
	* unwind-dw2.c (execute_cfa_program):  Only multiplexing
	DW_CFA_GNU_window_save for AArch64 and LP64.

gcc/testsuite/
	* testsuite/gcc.target/aarch64/return_address_sign_1.c: Enable on LP64
	only.
	* testsuite/gcc.target/aarch64/return_address_sign_2.c: Likewise.
	* testsuite/gcc.target/aarch64/return_address_sign_3.c: Likewise.

From-SVN: r244732

gcc/ChangeLog

@@ -1,3 +1,8 @@
+2017-01-20  Jiong Wang  <jiong.wang@arm.com>
+
+	* config/aarch64/aarch64-builtins.c (aarch64_init_builtins): Register
+	register pauth builtins for LP64 only.
+
 2017-01-20  Marek Polacek  <polacek@redhat.com>
 
 	PR c/79152

gcc/config/aarch64/aarch64-builtins.c

@@ -984,7 +984,12 @@ aarch64_init_builtins (void)
   aarch64_init_builtin_rsqrt ();
 
   /* Initialize pointer authentication builtins which are backed by instructions
-   in NOP encoding space.  */
+     in NOP encoding space.
+
+     NOTE: these builtins are supposed to be used by libgcc unwinder only, as
+     there is no support on return address signing under ILP32, we don't
+     register them.  */
+  if (!TARGET_ILP32)
     aarch64_init_pauth_hint_builtins ();
 }
 

gcc/testsuite/ChangeLog

@@ -1,3 +1,10 @@
+2017-01-20  Jiong Wang  <jiong.wang@arm.com>
+
+	* testsuite/gcc.target/aarch64/return_address_sign_1.c: Enable on LP64
+	only.
+	* testsuite/gcc.target/aarch64/return_address_sign_2.c: Likewise.
+	* testsuite/gcc.target/aarch64/return_address_sign_3.c: Likewise.
+
 2017-01-20  Nathan Sidwell  <nathan@acm.org>
 
 	PR c++/79495

gcc/testsuite/gcc.target/aarch64/return_address_sign_1.c

@@ -1,6 +1,7 @@
 /* Testing return address signing where no combined instructions used.  */
 /* { dg-do compile } */
 /* { dg-options "-O2 -msign-return-address=all" } */
+/* { dg-require-effective-target lp64 } */
 
 int foo (int);
 

gcc/testsuite/gcc.target/aarch64/return_address_sign_2.c

@@ -1,6 +1,7 @@
 /* Testing return address signing where combined instructions used.  */
 /* { dg-do compile } */
 /* { dg-options "-O2 -msign-return-address=all" } */
+/* { dg-require-effective-target lp64 } */
 
 int foo (int);
 int bar (int, int);

gcc/testsuite/gcc.target/aarch64/return_address_sign_3.c

@@ -1,6 +1,7 @@
 /* Testing the disable of return address signing.  */
 /* { dg-do compile } */
 /* { dg-options "-O2 -msign-return-address=all" } */
+/* { dg-require-effective-target lp64 } */
 
 int bar (int, int);
 

libgcc/ChangeLog

@@ -1,3 +1,9 @@
+2017-01-20  Jiong Wang  <jiong.wang@arm.com>
+
+	* config/aarch64/aarch64-unwind.h: Empty this file on ILP32.
+	* unwind-dw2.c (execute_cfa_program):  Only multiplexing
+	DW_CFA_GNU_window_save for AArch64 and LP64.
+
 2017-01-20  Jiong Wang  <jiong.wang@arm.com>
 
 	* config/aarch64/linux-unwind.h: Always include aarch64-unwind.h.

libgcc/config/aarch64/aarch64-unwind.h

@@ -22,7 +22,7 @@ a copy of the GCC Runtime Library Exception along with this program;
 see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
 <http://www.gnu.org/licenses/>.  */
 
-#ifndef AARCH64_UNWIND_H
+#if !defined (AARCH64_UNWIND_H) && !defined (__ILP32__)
 #define AARCH64_UNWIND_H
 
 #define DWARF_REGNUM_AARCH64_RA_STATE 34
@@ -84,4 +84,4 @@ aarch64_frob_update_context (struct _Unwind_Context *context,
   return;
 }
 
-#endif /* defined AARCH64_UNWIND_H */
+#endif /* defined AARCH64_UNWIND_H && defined __ILP32__ */

libgcc/unwind-dw2.c

@@ -1187,7 +1187,7 @@ execute_cfa_program (const unsigned char *insn_ptr,
 	  break;
 
 	case DW_CFA_GNU_window_save:
-#ifdef __aarch64__
+#if defined (__aarch64__) && !defined (__ILP32__)
 	  /* This CFA is multiplexed with Sparc.  On AArch64 it's used to toggle
 	     return address signing status.  */
 	  fs->regs.reg[DWARF_REGNUM_AARCH64_RA_STATE].loc.offset ^= 1;