re PR libstdc++/81706 (std::sin vectorization bug)

	PR libstdc++/81706
	* attribs.c (attribute_value_equal): Use omp_declare_simd_clauses_equal
	for comparison of OMP_CLAUSEs regardless of flag_openmp{,_simd}.
	(duplicate_one_attribute, copy_attributes_to_builtin): New functions.
	* attribs.h (duplicate_one_attribute, copy_attributes_to_builtin): New
	declarations.

	* c-decl.c (merge_decls): Copy "omp declare simd" attributes from
	newdecl to corresponding __builtin_ if any.

	* decl.c (duplicate_decls): Copy "omp declare simd" attributes from
	newdecl to corresponding __builtin_ if any.

	* gcc.target/i386/pr81706.c: New test.
	* g++.dg/ext/pr81706.C: New test.

From-SVN: r254069

gcc/ChangeLog

+2017-10-25  Jakub Jelinek  <jakub@redhat.com>
+
+	PR libstdc++/81706
+	* attribs.c (attribute_value_equal): Use omp_declare_simd_clauses_equal
+	for comparison of OMP_CLAUSEs regardless of flag_openmp{,_simd}.
+	(duplicate_one_attribute, copy_attributes_to_builtin): New functions.
+	* attribs.h (duplicate_one_attribute, copy_attributes_to_builtin): New
+	declarations.
+
 2017-10-25  Richard Biener  <rguenther@suse.de>
 
 	* tree-ssa-pre.c (need_eh_cleanup, need_ab_cleanup, el_to_remove,

gcc/attribs.c

@@ -1125,9 +1125,9 @@ attribute_value_equal (const_tree attr1, const_tree attr2)
 				     TREE_VALUE (attr2)) == 1);
     }
 
-  if ((flag_openmp || flag_openmp_simd)
-      && TREE_VALUE (attr1) && TREE_VALUE (attr2)
+  if (TREE_VALUE (attr1)
       && TREE_CODE (TREE_VALUE (attr1)) == OMP_CLAUSE
+      && TREE_VALUE (attr2)
       && TREE_CODE (TREE_VALUE (attr2)) == OMP_CLAUSE)
     return omp_declare_simd_clauses_equal (TREE_VALUE (attr1),
 					   TREE_VALUE (attr2));
@@ -1322,6 +1322,44 @@ merge_decl_attributes (tree olddecl, tree newdecl)
 			   DECL_ATTRIBUTES (newdecl));
 }
 
+/* Duplicate all attributes with name NAME in ATTR list to *ATTRS if
+   they are missing there.  */
+
+void
+duplicate_one_attribute (tree *attrs, tree attr, const char *name)
+{
+  attr = lookup_attribute (name, attr);
+  if (!attr)
+    return;
+  tree a = lookup_attribute (name, *attrs);
+  while (attr)
+    {
+      tree a2;
+      for (a2 = a; a2; a2 = lookup_attribute (name, TREE_CHAIN (a2)))
+	if (attribute_value_equal (attr, a2))
+	  break;
+      if (!a2)
+	{
+	  a2 = copy_node (attr);
+	  TREE_CHAIN (a2) = *attrs;
+	  *attrs = a2;
+	}
+      attr = lookup_attribute (name, TREE_CHAIN (attr));
+    }
+}
+
+/* Duplicate all attributes from user DECL to the corresponding
+   builtin that should be propagated.  */
+
+void
+copy_attributes_to_builtin (tree decl)
+{
+  tree b = builtin_decl_explicit (DECL_FUNCTION_CODE (decl));
+  if (b)
+    duplicate_one_attribute (&DECL_ATTRIBUTES (b),
+			     DECL_ATTRIBUTES (decl), "omp declare simd");
+}
+
 #if TARGET_DLLIMPORT_DECL_ATTRIBUTES
 
 /* Specialization of merge_decl_attributes for various Windows targets.

gcc/attribs.h

@@ -77,6 +77,16 @@ extern tree remove_attribute (const char *, tree);
 
 extern tree merge_attributes (tree, tree);
 
+/* Duplicate all attributes with name NAME in ATTR list to *ATTRS if
+   they are missing there.  */
+
+extern void duplicate_one_attribute (tree *, tree, const char *);
+
+/* Duplicate all attributes from user DECL to the corresponding
+   builtin that should be propagated.  */
+
+extern void copy_attributes_to_builtin (tree);
+
 /* Given two Windows decl attributes lists, possibly including
    dllimport, return a list of their union .  */
 extern tree merge_dllimport_decl_attributes (tree, tree);

gcc/c/ChangeLog

+2017-10-25  Jakub Jelinek  <jakub@redhat.com>
+
+	PR libstdc++/81706
+	* c-decl.c (merge_decls): Copy "omp declare simd" attributes from
+	newdecl to corresponding __builtin_ if any.
+
 2017-10-24  Paolo Carlini  <paolo.carlini@oracle.com>
 
 	PR c++/82466

gcc/c/c-decl.c

@@ -2570,6 +2570,8 @@ merge_decls (tree newdecl, tree olddecl, tree newtype, tree oldtype)
 			set_builtin_decl_declared_p (fncode, true);
 		      break;
 		    }
+
+		  copy_attributes_to_builtin (newdecl);
 		}
 	    }
 	  else

gcc/cp/ChangeLog

+2017-10-25  Jakub Jelinek  <jakub@redhat.com>
+
+	PR libstdc++/81706
+	* decl.c (duplicate_decls): Copy "omp declare simd" attributes from
+	newdecl to corresponding __builtin_ if any.
+
 2017-10-24  Paolo Carlini  <paolo.carlini@oracle.com>
 
 	PR c++/82466

gcc/cp/decl.c

@@ -2478,6 +2478,8 @@ next_arg:;
 		  break;
 		}
 	    }
+
+	  copy_attributes_to_builtin (newdecl);
 	}
       if (new_defines_function)
 	/* If defining a function declared with other language

gcc/testsuite/ChangeLog

+2017-10-25  Jakub Jelinek  <jakub@redhat.com>
+
+	PR libstdc++/81706
+	* gcc.target/i386/pr81706.c: New test.
+	* g++.dg/ext/pr81706.C: New test.
+
 2017-10-24  Jakub Jelinek  <jakub@redhat.com>
 
 	PR target/82460

gcc/testsuite/g++.dg/ext/pr81706.C

+// PR libstdc++/81706
+// { dg-do compile { target i?86-*-* x86_64-*-* } }
+// { dg-options "-O3 -mavx2 -mno-avx512f" }
+// { dg-final { scan-assembler "call\[^\n\r]_ZGVdN4v_cos" } }
+// { dg-final { scan-assembler "call\[^\n\r]_ZGVdN4v_sin" } }
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+extern double cos (double) __attribute__ ((nothrow, leaf, simd ("notinbranch")));
+extern double sin (double) __attribute__ ((nothrow, leaf, simd ("notinbranch")));
+#ifdef __cplusplus
+}
+#endif
+double p[1024] = { 1.0 };
+double q[1024] = { 1.0 };
+
+void
+foo (void)
+{
+  int i;
+  for (i = 0; i < 1024; i++)
+    p[i] = cos (q[i]);
+}
+
+void
+bar (void)
+{
+  int i;
+  for (i = 0; i < 1024; i++)
+    p[i] = __builtin_sin (q[i]);
+}

gcc/testsuite/gcc.target/i386/pr81706.c

+/* PR libstdc++/81706 */
+/* { dg-do compile } */
+/* { dg-options "-O3 -mavx2 -mno-avx512f" } */
+/* { dg-final { scan-assembler "call\[^\n\r]_ZGVdN4v_cos" } } */
+/* { dg-final { scan-assembler "call\[^\n\r]_ZGVdN4v_sin" } } */
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+extern double cos (double) __attribute__ ((nothrow, leaf, simd ("notinbranch")));
+extern double sin (double) __attribute__ ((nothrow, leaf, simd ("notinbranch")));
+#ifdef __cplusplus
+}
+#endif
+double p[1024] = { 1.0 };
+double q[1024] = { 1.0 };
+
+void
+foo (void)
+{
+  int i;
+  for (i = 0; i < 1024; i++)
+    p[i] = cos (q[i]);
+}
+
+void
+bar (void)
+{
+  int i;
+  for (i = 0; i < 1024; i++)
+    p[i] = __builtin_sin (q[i]);
+}