PATCH: Add SymbianOS "notshared" attribute

[Mark Mitchell <mark at codesourcery dot com>]

This patch adds support for __declspec(notshared), which is used on
Symbian OS as an equivalent to __attribute__((visibility("hidden")))
on class types.

Tested lightly, applied on the csl-arm-branch and on the mainline.

--
Mark Mitchell
CodeSourcery, LLC
mark@codesourcery.com

2004-11-04  Mark Mitchell  <mark@codesourcery.com>

	* config/arm/arm.c (arm_handle_notshared_attribute): New function.
	* doc/extend.texi: Document "notshared" attribute.
	
2004-11-04  Mark Mitchell  <mark@codesourcery.com>

	* testsuite/g++.dg/ext/visibility/symbian1.C: New test.
	
Index: config/arm/arm.c
===================================================================
RCS file: /cvs/gcc/gcc/gcc/config/arm/arm.c,v
retrieving revision 1.303.2.61
diff -c -5 -p -r1.303.2.61 arm.c
*** config/arm/arm.c	3 Nov 2004 19:11:05 -0000	1.303.2.61
--- config/arm/arm.c	4 Nov 2004 23:34:32 -0000
*************** static unsigned long arm_compute_save_re
*** 111,120 ****
--- 111,121 ----
  static unsigned long arm_compute_save_reg_mask (void);
  static unsigned long arm_isr_value (tree);
  static unsigned long arm_compute_func_type (void);
  static tree arm_handle_fndecl_attribute (tree *, tree, tree, int, bool *);
  static tree arm_handle_isr_attribute (tree *, tree, tree, int, bool *);
+ static tree arm_handle_notshared_attribute (tree *, tree, tree, int, bool *);
  static void arm_output_function_epilogue (FILE *, HOST_WIDE_INT);
  static void arm_output_function_prologue (FILE *, HOST_WIDE_INT);
  static void thumb_output_function_prologue (FILE *, HOST_WIDE_INT);
  static int arm_comp_type_attributes (tree, tree);
  static void arm_set_default_type_attributes (tree);
*************** const struct attribute_spec arm_attribut
*** 2611,2620 ****
--- 2612,2622 ----
    { "dllexport",    0, 0, true,  false, false, NULL },
    { "interfacearm", 0, 0, true,  false, false, arm_handle_fndecl_attribute },
  #elif TARGET_DLLIMPORT_DECL_ATTRIBUTES
    { "dllimport",    0, 0, false, false, false, handle_dll_attribute },
    { "dllexport",    0, 0, false, false, false, handle_dll_attribute },
+   { "notshared",    0, 0, false, true, false, arm_handle_notshared_attribute },
  #endif
    { NULL,           0, 0, false, false, false, NULL }
  };
  
  /* Handle an attribute requiring a FUNCTION_DECL;
*************** arm_handle_isr_attribute (tree *node, tr
*** 2690,2699 ****
--- 2692,2724 ----
      }
  
    return NULL_TREE;
  }
  
+ /* Handle the "notshared" attribute.  This attribute is another way of
+    requesting hidden visibility.  ARM's compiler supports
+    "__declspec(notshared)"; we support the same thing via an
+    attribute.  */
+ 
+ static tree
+ arm_handle_notshared_attribute (tree *node, 
+ 				tree name ATTRIBUTE_UNUSED, 
+ 				tree args ATTRIBUTE_UNUSED, 
+ 				int flags ATTRIBUTE_UNUSED, 
+ 				bool *no_add_attrs)
+ {
+   tree decl = TYPE_NAME (*node);
+ 
+   if (decl)
+     {
+       DECL_VISIBILITY (decl) = VISIBILITY_HIDDEN;
+       DECL_VISIBILITY_SPECIFIED (decl) = 1;
+       *no_add_attrs = false;
+     }
+   return NULL_TREE;
+ }
+ 
  /* Return 0 if the attributes for two types are incompatible, 1 if they
     are compatible, and 2 if they are nearly compatible (which causes a
     warning to be generated).  */
  static int
  arm_comp_type_attributes (tree type1, tree type2)
Index: testsuite/g++.dg/ext/visibility/symbian1.C
===================================================================
RCS file: testsuite/g++.dg/ext/visibility/symbian1.C
diff -N testsuite/g++.dg/ext/visibility/symbian1.C
*** /dev/null	1 Jan 1970 00:00:00 -0000
--- testsuite/g++.dg/ext/visibility/symbian1.C	4 Nov 2004 23:34:32 -0000
***************
*** 0 ****
--- 1,22 ----
+ // { dg-do compile { target arm*-*-symbianelf* } }
+ // Class data should not be exported.
+ // { dg-final { scan-hidden "_ZTV2K3" } }
+ // But the constructor and destructor should be exported.
+ // { dg-final { scan-not-hidden "_ZN2K3C2Ev" } }
+ // { dg-final { scan-not-hidden "_ZN2K3D0Ev" } }
+ 
+ class __declspec(notshared) K3 {
+ public:
+   __declspec(dllimport) K3();
+   __declspec(dllimport) virtual ~K3();
+   virtual int m1();
+ };
+ 
+ __declspec(dllexport)
+   K3::K3(){}
+ 
+ __declspec(dllexport)
+   K3::~K3(){}
+ 
+ int K3::m1() { return 1; }
+ 
Index: doc/extend.texi
===================================================================
RCS file: /cvs/gcc/gcc/gcc/doc/extend.texi,v
retrieving revision 1.228
diff -c -5 -p -r1.228 extend.texi
*** doc/extend.texi	1 Nov 2004 18:24:28 -0000	1.228
--- doc/extend.texi	5 Nov 2004 00:14:32 -0000
*************** main (void)
*** 3305,3314 ****
--- 3305,3337 ----
  If you replaced @code{short_a} with @code{short} in the variable
  declaration, the above program would abort when compiled with
  @option{-fstrict-aliasing}, which is on by default at @option{-O2} or
  above in recent GCC versions.
  
+ @subsection ARM Type Attributes
+ 
+ On those ARM targets that support @code{dllimport} (such as Symbian
+ OS), you can use the @code{notshared} attribute to indicate that the 
+ virtual table and other similar data for a class should not be
+ exported from a DLL.  For example:
+ 
+ @smallexample
+ class __declspec(notshared) C @{
+ public:
+   __declspec(dllimport) C(); 
+   virtual void f();
+ @}
+ 
+ __declspec(dllexport)
+ C::C() @{@}
+ @end smallexample
+ 
+ In this code, @code{C::C} is exported from the current DLL, but the
+ virtual table for @code{C} is not exported.  (You can use
+ @code{__attribute__} instead of @code{__declspec} if you prefer, but
+ most Symbian OS code uses @code{__declspec}.)
+ 
  @subsection i386 Type Attributes
  
  Two attributes are currently defined for i386 configurations:
  @code{ms_struct} and @code{gcc_struct}