Implement TARGET_HANDLE_GENERIC_ATTRIBUTE

gcc/ChangeLog:

2019-09-03  Jozef Lawrynowicz  <jozef.l@mittosystems.com>

	* config/msp430/msp430.c (TARGET_HANDLE_GENERIC_ATTRIBUTE): Define.
	(msp430_handle_generic_attribute): New function.
	* doc/tm.texi: Regenerate.
	* doc/tm.texi.in: Add TARGET_HANDLE_GENERIC_ATTRIBUTE.
	* hooks.c (hook_tree_treeptr_tree_tree_int_boolptr_null): New.
	* hooks.h (hook_tree_treeptr_tree_tree_int_boolptr_null): New.
	* target.def: Define new hook TARGET_HANDLE_GENERIC_ATTRIBUTE.

gcc/c-family/ChangeLog:

2019-09-03  Jozef Lawrynowicz  <jozef.l@mittosystems.com>

	* c-attribs.c (handle_section_attribute): Call the
	handle_generic_attribute target hook after performing target
	independent processing.
	(handle_noinit_attribute): Likewise.

From-SVN: r275355

9 files changed, 114 insertions, 10 deletions

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index abbbf16..e65e304 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,13 @@
+2019-09-03  Jozef Lawrynowicz  <jozef.l@mittosystems.com>
+
+	* config/msp430/msp430.c (TARGET_HANDLE_GENERIC_ATTRIBUTE): Define.
+	(msp430_handle_generic_attribute): New function.
+	* doc/tm.texi: Regenerate.
+	* doc/tm.texi.in: Add TARGET_HANDLE_GENERIC_ATTRIBUTE.
+	* hooks.c (hook_tree_treeptr_tree_tree_int_boolptr_null): New.
+	* hooks.h (hook_tree_treeptr_tree_tree_int_boolptr_null): New.
+	* target.def: Define new hook TARGET_HANDLE_GENERIC_ATTRIBUTE.
+
 2019-09-03  Kamlesh Kumar  <kamleshbhalui@gmail.com>
 
 	PR tree-optimization/91504
diff --git a/gcc/c-family/ChangeLog b/gcc/c-family/ChangeLog
index e4f011d..9ca5a1e 100644
--- a/gcc/c-family/ChangeLog
+++ b/gcc/c-family/ChangeLog
@@ -1,3 +1,10 @@
+2019-09-03  Jozef Lawrynowicz  <jozef.l@mittosystems.com>
+
+	* c-attribs.c (handle_section_attribute): Call the
+	handle_generic_attribute target hook after performing target
+	independent processing.
+	(handle_noinit_attribute): Likewise.
+
 2019-09-03  Ian Lance Taylor  <iant@golang.org>
 
 	* c-cppbuiltin.c (builtin_define_with_hex_fp_value): Always expand
diff --git a/gcc/c-family/c-attribs.c b/gcc/c-family/c-attribs.c
index 820c83f..6500b99 100644
--- a/gcc/c-family/c-attribs.c
+++ b/gcc/c-family/c-attribs.c
@@ -1875,6 +1875,7 @@ handle_section_attribute (tree *node, tree ARG_UNUSED (name), tree args,
 			  int ARG_UNUSED (flags), bool *no_add_attrs)
 {
   tree decl = *node;
+  tree res = NULL_TREE;
 
   if (!targetm_common.have_named_sections)
     {
@@ -1922,12 +1923,20 @@ handle_section_attribute (tree *node, tree ARG_UNUSED (name), tree args,
       goto fail;
     }
 
-  set_decl_section_name (decl, TREE_STRING_POINTER (TREE_VALUE (args)));
-  return NULL_TREE;
+  res = targetm.handle_generic_attribute (node, name, args, flags,
+					  no_add_attrs);
+
+  /* If the back end confirms the attribute can be added then continue onto
+     final processing.  */
+  if (!(*no_add_attrs))
+    {
+      set_decl_section_name (decl, TREE_STRING_POINTER (TREE_VALUE (args)));
+      return res;
+    }
 
 fail:
   *no_add_attrs = true;
-  return NULL_TREE;
+  return res;
 }
 
 /* If in c++-11, check if the c++-11 alignment constraint with respect
@@ -2249,6 +2258,7 @@ handle_noinit_attribute (tree * node,
 		  bool *no_add_attrs)
 {
   const char *message = NULL;
+  tree res = NULL_TREE;
 
   gcc_assert (DECL_P (*node));
   gcc_assert (args == NULL);
@@ -2271,14 +2281,23 @@ handle_noinit_attribute (tree * node,
       *no_add_attrs = true;
     }
   else
-    /* If this var is thought to be common, then change this.  Common
-       variables are assigned to sections before the backend has a
-       chance to process them.  Do this only if the attribute is
-       valid.  */
-    if (DECL_COMMON (*node))
-      DECL_COMMON (*node) = 0;
+    {
+      res = targetm.handle_generic_attribute (node, name, args, flags,
+					      no_add_attrs);
+      /* If the back end confirms the attribute can be added then continue onto
+	 final processing.  */
+      if (!(*no_add_attrs))
+	{
+	  /* If this var is thought to be common, then change this.  Common
+	     variables are assigned to sections before the backend has a
+	     chance to process them.  Do this only if the attribute is
+	     valid.  */
+	  if (DECL_COMMON (*node))
+	    DECL_COMMON (*node) = 0;
+	}
+    }
 
-  return NULL_TREE;
+  return res;
 }
 
 
diff --git a/gcc/config/msp430/msp430.c b/gcc/config/msp430/msp430.c
index c5cf704..1e61075 100644
--- a/gcc/config/msp430/msp430.c
+++ b/gcc/config/msp430/msp430.c
@@ -1518,6 +1518,46 @@ const struct attribute_spec msp430_attribute_table[] =
     { NULL,		0, 0, false, false, false, false, NULL,  NULL }
   };
 
+#undef TARGET_HANDLE_GENERIC_ATTRIBUTE
+#define TARGET_HANDLE_GENERIC_ATTRIBUTE msp430_handle_generic_attribute
+
+tree
+msp430_handle_generic_attribute (tree *node,
+				 tree   name,
+				 tree   args ATTRIBUTE_UNUSED,
+				 int    flags ATTRIBUTE_UNUSED,
+				 bool *no_add_attrs)
+
+{
+  const char *message = NULL;
+
+  if (!(TREE_NAME_EQ (name, ATTR_NOINIT) || TREE_NAME_EQ (name, "section")))
+    return NULL_TREE;
+
+  /* The front end has set up an exclusion between the "noinit" and "section"
+     attributes.  */
+  if (has_attr (ATTR_LOWER, *node))
+    message = G_("ignoring attribute %qE because it conflicts with "
+		 "attribute %<lower%>");
+  else if (has_attr (ATTR_UPPER, *node))
+    message = G_("ignoring attribute %qE because it conflicts with "
+		 "attribute %<upper%>");
+  else if (has_attr (ATTR_EITHER, *node))
+    message = G_("ignoring attribute %qE because it conflicts with "
+		 "attribute %<either%>");
+  else if (has_attr (ATTR_PERSIST, *node))
+    message = G_("ignoring attribute %qE because it conflicts with "
+		 "attribute %<persistent%>");
+
+  if (message)
+    {
+      warning (OPT_Wattributes, message, name);
+      *no_add_attrs = true;
+    }
+
+  return NULL_TREE;
+}
+
 #undef  TARGET_ASM_FUNCTION_PROLOGUE
 #define TARGET_ASM_FUNCTION_PROLOGUE	msp430_start_function
 
diff --git a/gcc/doc/tm.texi b/gcc/doc/tm.texi
index 5506908..0b5a08d 100644
--- a/gcc/doc/tm.texi
+++ b/gcc/doc/tm.texi
@@ -10391,6 +10391,14 @@ attributes, or a copy of the list may be made if further changes are
 needed.
 @end deftypefn
 
+@deftypefn {Target Hook} tree TARGET_HANDLE_GENERIC_ATTRIBUTE (tree *@var{node}, tree @var{name}, tree @var{args}, int @var{flags}, bool *@var{no_add_attrs})
+Define this target hook if you want to be able to perform additional
+target-specific processing of an attribute which is handled generically
+by a front end.  The arguments are the same as those which are passed to
+attribute handlers.  So far this only affects the @var{noinit} and
+@var{section} attribute.
+@end deftypefn
+
 @deftypefn {Target Hook} bool TARGET_FUNCTION_ATTRIBUTE_INLINABLE_P (const_tree @var{fndecl})
 @cindex inlining
 This target hook returns @code{true} if it is OK to inline @var{fndecl}
diff --git a/gcc/doc/tm.texi.in b/gcc/doc/tm.texi.in
index 98e7100..a920055 100644
--- a/gcc/doc/tm.texi.in
+++ b/gcc/doc/tm.texi.in
@@ -7200,6 +7200,8 @@ on this implementation detail.
 
 @hook TARGET_INSERT_ATTRIBUTES
 
+@hook TARGET_HANDLE_GENERIC_ATTRIBUTE
+
 @hook TARGET_FUNCTION_ATTRIBUTE_INLINABLE_P
 
 @hook TARGET_OPTION_VALID_ATTRIBUTE_P
diff --git a/gcc/hooks.c b/gcc/hooks.c
index f95659b..ca731c4 100644
--- a/gcc/hooks.c
+++ b/gcc/hooks.c
@@ -442,6 +442,12 @@ hook_tree_tree_tree_tree_null (tree, tree, tree)
   return NULL;
 }
 
+tree
+hook_tree_treeptr_tree_tree_int_boolptr_null (tree *, tree, tree, int, bool *)
+{
+  return NULL;
+}
+
 /* Generic hook that takes an rtx_insn *and returns a NULL string.  */
 const char *
 hook_constcharptr_const_rtx_insn_null (const rtx_insn *)
diff --git a/gcc/hooks.h b/gcc/hooks.h
index 0bc8117..040eff0 100644
--- a/gcc/hooks.h
+++ b/gcc/hooks.h
@@ -109,6 +109,7 @@ extern tree hook_tree_void_null (void);
 extern tree hook_tree_tree_tree_null (tree, tree);
 extern tree hook_tree_tree_tree_tree_null (tree, tree, tree);
 extern tree hook_tree_tree_int_treep_bool_null (tree, int, tree *, bool);
+extern tree hook_tree_treeptr_tree_tree_int_boolptr_null (tree *, tree, tree, int, bool *);
 
 extern unsigned hook_uint_void_0 (void);
 extern unsigned int hook_uint_mode_0 (machine_mode);
diff --git a/gcc/target.def b/gcc/target.def
index b2332d8..ca7e7ad 100644
--- a/gcc/target.def
+++ b/gcc/target.def
@@ -2208,6 +2208,17 @@ needed.",
  void, (tree node, tree *attr_ptr),
  hook_void_tree_treeptr)
 
+/* Perform additional target-specific processing of generic attributes.  */
+DEFHOOK
+(handle_generic_attribute,
+ "Define this target hook if you want to be able to perform additional\n\
+target-specific processing of an attribute which is handled generically\n\
+by a front end.  The arguments are the same as those which are passed to\n\
+attribute handlers.  So far this only affects the @var{noinit} and\n\
+@var{section} attribute.",
+ tree, (tree *node, tree name, tree args, int flags, bool *no_add_attrs),
+ hook_tree_treeptr_tree_tree_int_boolptr_null)
+
 /* Return true if FNDECL (which has at least one machine attribute)
    can be inlined despite its machine attributes, false otherwise.  */
 DEFHOOK