[Patch ARM] Fix PR71778

gcc/

	PR target/71778
	* config/arm/arm-builtins.c (arm_expand_builtin_args): Return TARGET
	if given a non-constant argument for an intrinsic which requires a
	constant.

gcc/testsuite/

	PR target/71778
	* gcc.target/arm/pr71778.c: New.

From-SVN: r249272

gcc/ChangeLog

+2017-06-16  James Greenhalgh  <james.greenhalgh@arm.com>
+
+	PR target/71778
+	* config/arm/arm-builtins.c (arm_expand_builtin_args): Return TARGET
+	if given a non-constant argument for an intrinsic which requires a
+	constant.
+
 2017-06-16  Jan Hubicka  <hubicka@ucw.cz>
 
 	* profile.c (compare_freqs): New function.

gcc/config/arm/arm-builtins.c

@@ -2245,7 +2245,12 @@ constant_arg:
 		{
 		  error ("%Kargument %d must be a constant immediate",
 			 exp, argc + 1);
-		  return const0_rtx;
+		  /* We have failed to expand the pattern, and are safely
+		     in to invalid code.  But the mid-end will still try to
+		     build an assignment for this node while it expands,
+		     before stopping for the error, just pass it back
+		     TARGET to ensure a valid assignment.  */
+		  return target;
 		}
 	      break;
 

gcc/testsuite/ChangeLog

+2017-06-16  James Greenhalgh  <james.greenhalgh@arm.com>
+
+	PR target/71778
+	* gcc.target/arm/pr71778.c: New.
+
 2017-06-16  Jan Hubicka  <hubicka@ucw.cz>
 
 	* gcc.dg/tree-ssa/ssa-lim-11.c: Disable branch prediction.

gcc/testsuite/gcc.target/arm/pr71778.c

+/* { dg-do compile }  */
+/* { dg-require-effective-target arm_neon_ok } */
+/* { dg-options "-O2" } */
+/* { dg-add-options arm_neon } */
+
+typedef __simd128_int32_t int32x4_t;
+
+__extension__ extern __inline int32x4_t
+__attribute__  ((__always_inline__, __gnu_inline__, __artificial__))
+vshrq_n_s32 (int32x4_t __a, const int __b)
+{
+  /* Errors for arm_neon.h intrinsics using constants end up on the line
+     in arm_neon.h rather than the source file line.  That means we
+     need to put the dg-error up here, rather than on line 22 where we'd
+     like it.  */
+  return (int32x4_t)__builtin_neon_vshrs_nv4si (__a, __b); /* { dg-error "argument 2 must be a constant immediate" } */
+}
+
+int32x4_t
+shift (int32x4_t a, int b)
+{
+  return vshrq_n_s32 (a, b);
+}
+