Support for dllimport and dllexport attributes for i386-pe.

	* tree.h (DECL_NON_ADDR_CONST_P): New accessor macro.
	(struct tree_decl): Add non_addr_const_p field.
	* tree.c (staticp): Use.
	* i386/cygwin32.h (CPP_PREDEFINES): Map __declspec(x) to GCC
	attributes.
	(SUBTARGET_SWITCHES): Switches to turn on/off dllimport|export
	attributes. Also accept -mwindows option.
	(VALID_MACHINE_DECL_ATTRIBUTE): New macro.
	(MERGE_MACHINE_DECL_ATTRIBUTE): New macro.
	(REDO_SECTION_INFO_P): New macro.
	(DRECTVE_SECTION_FUNCTION): New macro.
	(drectve_section): Cover function to implement above.
	(SWITCH_TO_SECTION_FUNCTION): New macro.
	(switch_to_section): Covert function to implement above.
	(EXTRA_SECTIONS): Add in_drectve.
	(EXTRA_SECTION_FUNCTIONS): Add in_drectve and switch_to_section.
	(ENCODE_SECTION_INFO): Delete old macro and redefine as a function.
	(STRIP_NAME_ENCODING): Handle new attributes.
	(ASM_OUTPUT_LABELREF): New macro.
	(ASM_OUTPUT_FUNCTION_NAME): New macro.
	(ASM_OUTPUT_COMMON): New macro.
	(ASM_OUTPUT_DECLARE_OBJECT_NAME): New macro.
	* i386/mingw32.h (CPP_PREDEFINES): Map __declspec(x) to GCC
	attributes.
	* i386/winnt.c (i386_pe_valid_decl_attribute_p): New function.
	(i386_pe_merge_decl_attributes): New function.
	(i386_pe_check_vtable_importexport): New function.
	(i386_pe_dllexport_p): New function.
	(i386_pe_dllimport_p): New function.
	(i386_pe_dllexport_name_p): New function.
	(i386_pe_dllimport_name_p): New function.
	(i386_pe_mark_dllexport): New function.
	(i386_pe_mark_dllimport): New function.
	(i386_pe_encode_section_info): New function.
	(i386_pe_unique_section): Strip encoding from name first.

From-SVN: r20983

gcc/ChangeLog

+Tue Jul  7 01:03:03 1998  Mumit Khan <khan@xraylith.wisc.edu>
+
+	Support for dllimport and dllexport attributes for i386-pe.
+
+	* tree.h (DECL_NON_ADDR_CONST_P): New accessor macro.
+	(struct tree_decl): Add non_addr_const_p field.
+	* tree.c (staticp): Use.
+
+	* i386/cygwin32.h (CPP_PREDEFINES): Map __declspec(x) to GCC
+	attributes.
+	(SUBTARGET_SWITCHES): Switches to turn on/off dllimport|export
+	attributes. Also accept -mwindows option.
+	(VALID_MACHINE_DECL_ATTRIBUTE): New macro.
+	(MERGE_MACHINE_DECL_ATTRIBUTE): New macro.
+	(REDO_SECTION_INFO_P): New macro.
+	(DRECTVE_SECTION_FUNCTION): New macro.
+	(drectve_section): Cover function to implement above.
+	(SWITCH_TO_SECTION_FUNCTION): New macro.
+	(switch_to_section): Covert function to implement above.
+	(EXTRA_SECTIONS): Add in_drectve.
+	(EXTRA_SECTION_FUNCTIONS): Add in_drectve and switch_to_section.
+	(ENCODE_SECTION_INFO): Delete old macro and redefine as a function.
+	(STRIP_NAME_ENCODING): Handle new attributes.
+	(ASM_OUTPUT_LABELREF): New macro.
+	(ASM_OUTPUT_FUNCTION_NAME): New macro.
+	(ASM_OUTPUT_COMMON): New macro.
+	(ASM_OUTPUT_DECLARE_OBJECT_NAME): New macro.
+
+	* i386/mingw32.h (CPP_PREDEFINES): Map __declspec(x) to GCC
+	attributes.
+
+	* i386/winnt.c (i386_pe_valid_decl_attribute_p): New function.
+	(i386_pe_merge_decl_attributes): New function.
+	(i386_pe_check_vtable_importexport): New function.
+	(i386_pe_dllexport_p): New function.
+	(i386_pe_dllimport_p): New function.
+	(i386_pe_dllexport_name_p): New function.
+	(i386_pe_dllimport_name_p): New function.
+	(i386_pe_mark_dllexport): New function.
+	(i386_pe_mark_dllimport): New function.
+	(i386_pe_encode_section_info): New function.
+	(i386_pe_unique_section): Strip encoding from name first.
+
 Tue Jul  7 00:50:17 1998  Manfred Hollstein   (manfred@s-direktnet.de)
 
         * libgcc2.c (L_exit): Provide a fake for atexit on systems which

gcc/config/i386/cygwin32.h

@@ -30,6 +30,14 @@ Boston, MA 02111-1307, USA. */
 #include "i386/gas.h"
 #include "dbxcoff.h"
 
+/* Support the __declspec keyword by turning them into attributes.
+   We currently only support: dllimport and dllexport.
+   Note that the current way we do this may result in a collision with
+   predefined attributes later on.  This can be solved by using one attribute,
+   say __declspec__, and passing args to it.  The problem with that approach
+   is that args are not accumulated: each new appearance would clobber any
+   existing args.  */
+
 #ifdef CPP_PREDEFINES
 #undef CPP_PREDEFINES
 #endif
@@ -38,6 +46,7 @@ Boston, MA 02111-1307, USA. */
   -D__CYGWIN32__ -DWINNT  -D_X86_=1 -D__STDC__=1\
   -D__stdcall=__attribute__((__stdcall__)) \
   -D__cdecl=__attribute__((__cdecl__)) \
+  -D__declspec(x)=__attribute__((x)) \
   -Asystem(winnt) -Acpu(i386) -Amachine(i386)"
 
 #undef CPP_SPEC
@@ -69,13 +78,51 @@ Boston, MA 02111-1307, USA. */
 #define WCHAR_TYPE "short unsigned int"
 #define HAVE_ATEXIT 1
 
+
+/* Ignore dllimport for functions.  */
+#define TARGET_NOP_FUN_DLLIMPORT (target_flags & 0x20000)
+
+#undef SUBTARGET_SWITCHES
+#define SUBTARGET_SWITCHES 			\
+  { "nop-fun-dllimport",	 0x20000 },	\
+  { "no-nop-fun-dllimport",	-0x20000 },	\
+  { "windows",			 0x0     },
+
+/* A C expression whose value is nonzero if IDENTIFIER with arguments ARGS
+   is a valid machine specific attribute for DECL.
+   The attributes in ATTRIBUTES have previously been assigned to DECL.  */
+extern int i386_pe_valid_decl_attribute_p ();
+
+#undef VALID_MACHINE_DECL_ATTRIBUTE
+#define VALID_MACHINE_DECL_ATTRIBUTE(DECL, ATTRIBUTES, IDENTIFIER, ARGS) \
+  i386_pe_valid_decl_attribute_p (DECL, ATTRIBUTES, IDENTIFIER, ARGS)
+
+extern union tree_node *i386_pe_merge_decl_attributes ();
+#define MERGE_MACHINE_DECL_ATTRIBUTES(OLD, NEW) \
+  i386_pe_merge_decl_attributes ((OLD), (NEW))
+
+/* Used to implement dllexport overriding dllimport semantics.  It's also used
+   to handle vtables - the first pass won't do anything because
+   DECL_CONTEXT (DECL) will be 0 so i386_pe_dll{ex,im}port_p will return 0.
+   It's also used to handle dllimport override semantics.  */
+#if 0
+#define REDO_SECTION_INFO_P(DECL) \
+  ((DECL_MACHINE_ATTRIBUTES (DECL) != NULL_TREE) \
+   || (TREE_CODE (DECL) == VAR_DECL && DECL_VIRTUAL_P (DECL)))
+#else
+#define REDO_SECTION_INFO_P(DECL) 1
+#endif
+
+
 #undef EXTRA_SECTIONS
-#define EXTRA_SECTIONS in_ctor, in_dtor
+#define EXTRA_SECTIONS in_ctor, in_dtor, in_drectve
 
 #undef EXTRA_SECTION_FUNCTIONS
 #define EXTRA_SECTION_FUNCTIONS					\
   CTOR_SECTION_FUNCTION						\
-  DTOR_SECTION_FUNCTION
+  DTOR_SECTION_FUNCTION						\
+  DRECTVE_SECTION_FUNCTION					\
+  SWITCH_TO_SECTION_FUNCTION
 
 #define CTOR_SECTION_FUNCTION					\
 void								\
@@ -99,6 +146,41 @@ dtor_section ()							\
     }								\
 }
 
+#define DRECTVE_SECTION_FUNCTION \
+void									\
+drectve_section ()							\
+{									\
+  if (in_section != in_drectve)						\
+    {									\
+      fprintf (asm_out_file, "%s\n", "\t.section .drectve\n");		\
+      in_section = in_drectve;						\
+    }									\
+}
+
+/* Switch to SECTION (an `enum in_section').
+
+   ??? This facility should be provided by GCC proper.
+   The problem is that we want to temporarily switch sections in
+   ASM_DECLARE_OBJECT_NAME and then switch back to the original section
+   afterwards.  */
+#define SWITCH_TO_SECTION_FUNCTION 				\
+void 								\
+switch_to_section (section, decl) 				\
+     enum in_section section; 					\
+     tree decl; 						\
+{ 								\
+  switch (section) 						\
+    { 								\
+      case in_text: text_section (); break; 			\
+      case in_data: data_section (); break; 			\
+      case in_named: named_section (decl, NULL, 0); break; 	\
+      case in_ctor: ctor_section (); break; 			\
+      case in_dtor: dtor_section (); break; 			\
+      case in_drectve: drectve_section (); break; 		\
+      default: abort (); break; 				\
+    } 								\
+}
+
 #define ASM_OUTPUT_CONSTRUCTOR(FILE,NAME)	\
   do {						\
     ctor_section ();				\
@@ -111,7 +193,7 @@ dtor_section ()							\
   do {						\
     dtor_section ();                   		\
     fprintf (FILE, "%s\t", ASM_LONG);		\
-    assemble_name (FILE, NAME);              	\
+    assemble_name (FILE, NAME);			\
     fprintf (FILE, "\n");			\
   } while (0)
 
@@ -119,44 +201,38 @@ dtor_section ()							\
    differently depending on something about the variable or
    function named by the symbol (such as what section it is in).
 
-   On i386, if using PIC, mark a SYMBOL_REF for a non-global symbol
-   so that we may access it directly in the GOT.
-
    On i386 running Windows NT, modify the assembler name with a suffix 
    consisting of an atsign (@) followed by string of digits that represents
    the number of bytes of arguments passed to the function, if it has the 
-   attribute STDCALL. */
+   attribute STDCALL.
+
+   In addition, we must mark dll symbols specially. Definitions of 
+   dllexport'd objects install some info in the .drectve section.  
+   References to dllimport'd objects are fetched indirectly via
+   _imp__.  If both are declared, dllexport overrides.  This is also 
+   needed to implement one-only vtables: they go into their own
+   section and we need to set DECL_SECTION_NAME so we do that here.
+   Note that we can be called twice on the same decl.  */
+
+extern void i386_pe_encode_section_info ();
 
 #ifdef ENCODE_SECTION_INFO
 #undef ENCODE_SECTION_INFO
-#define ENCODE_SECTION_INFO(DECL) 					\
-do									\
-  {									\
-    if (flag_pic)							\
-      {									\
-	rtx rtl = (TREE_CODE_CLASS (TREE_CODE (DECL)) != 'd'		\
-		   ? TREE_CST_RTL (DECL) : DECL_RTL (DECL));		\
-	SYMBOL_REF_FLAG (XEXP (rtl, 0))					\
-	  = (TREE_CODE_CLASS (TREE_CODE (DECL)) != 'd'			\
-	     || ! TREE_PUBLIC (DECL));					\
-      }									\
-    if (TREE_CODE (DECL) == FUNCTION_DECL) 				\
-      if (lookup_attribute ("stdcall",					\
-			    TYPE_ATTRIBUTES (TREE_TYPE (DECL))))	\
-        XEXP (DECL_RTL (DECL), 0) = 					\
-          gen_rtx (SYMBOL_REF, Pmode, gen_stdcall_suffix (DECL)); 	\
-  }									\
-while (0)
 #endif
+#define ENCODE_SECTION_INFO(DECL) i386_pe_encode_section_info (DECL)
 
-/* This macro gets just the user-specified name out of the string in a
-   SYMBOL_REF.  Discard trailing @[NUM] encoded by ENCODE_SECTION_INFO.   */
+/* Utility used only in this file.  */
+#define I386_PE_STRIP_ENCODING(SYM_NAME) \
+  ((SYM_NAME) + ((SYM_NAME)[0] == '@' ? 3 : 0))
 
+/* This macro gets just the user-specified name
+   out of the string in a SYMBOL_REF.  Discard
+   trailing @[NUM] encoded by ENCODE_SECTION_INFO.  */
 #undef  STRIP_NAME_ENCODING
 #define STRIP_NAME_ENCODING(VAR,SYMBOL_NAME)				\
 do {									\
   char *_p;								\
-  char *_name = ((SYMBOL_NAME) + ((SYMBOL_NAME)[0] == '*'));		\
+  char *_name = I386_PE_STRIP_ENCODING (SYMBOL_NAME);			\
   for (_p = _name; *_p && *_p != '@'; ++_p)				\
     ;									\
   if (*_p == '@')							\
@@ -170,6 +246,62 @@ do {									\
     (VAR) = _name;							\
 } while (0)
       
+
+/* Output a reference to a label.  */
+#undef ASM_OUTPUT_LABELREF
+#define ASM_OUTPUT_LABELREF(STREAM, NAME)  		\
+  fprintf (STREAM, "%s%s", USER_LABEL_PREFIX, 		\
+           I386_PE_STRIP_ENCODING (NAME))		\
+
+/* Output a function definition label.  */
+#undef ASM_DECLARE_FUNCTION_NAME
+#define ASM_DECLARE_FUNCTION_NAME(STREAM, NAME, DECL)	\
+do {							\
+  if (i386_pe_dllexport_name_p (NAME))			\
+    {							\
+      drectve_section ();				\
+      fprintf ((STREAM), "\t.ascii \" -export:%s\"\n", 	\
+               I386_PE_STRIP_ENCODING (NAME));		\
+      function_section (DECL);				\
+    }							\
+  ASM_OUTPUT_LABEL ((STREAM), (NAME));			\
+} while (0)
+
+/* Output a common block.  */
+#undef ASM_OUTPUT_COMMON
+#define ASM_OUTPUT_COMMON(STREAM, NAME, SIZE, ROUNDED)	\
+do {							\
+  if (i386_pe_dllexport_name_p (NAME))			\
+    {							\
+      drectve_section ();				\
+      fprintf ((STREAM), "\t.ascii \" -export:%s\"\n",	\
+               I386_PE_STRIP_ENCODING (NAME));		\
+    }							\
+  if (! i386_pe_dllimport_name_p (NAME))		\
+    {							\
+      fprintf ((STREAM), "\t.comm\t"); 			\
+      assemble_name ((STREAM), (NAME));			\
+      fprintf ((STREAM), ", %d\t%s %d\n",		\
+	       (ROUNDED), ASM_COMMENT_START, (SIZE));	\
+    }							\
+} while (0)
+
+/* Output the label for an initialized variable.  */
+#undef ASM_DECLARE_OBJECT_NAME
+#define ASM_DECLARE_OBJECT_NAME(STREAM, NAME, DECL) 	\
+do {							\
+  if (i386_pe_dllexport_name_p (NAME))			\
+    {							\
+      enum in_section save_section = in_section;	\
+      drectve_section ();				\
+      fprintf ((STREAM), "\t.ascii \" -export:%s\"\n",	\
+               I386_PE_STRIP_ENCODING (NAME));		\
+      switch_to_section (save_section, (DECL));		\
+    }							\
+  ASM_OUTPUT_LABEL ((STREAM), (NAME));			\
+} while (0)
+
+
 /* Emit code to check the stack when allocating more that 4000
    bytes in one go. */
 

gcc/config/i386/mingw32.h

@@ -31,6 +31,7 @@ Boston, MA 02111-1307, USA. */
   -D__MINGW32__ -DWINNT  -D_X86_=1 -D__STDC__=1\
   -D__stdcall=__attribute__((__stdcall__)) \
   -D__cdecl=__attribute__((__cdecl__)) \
+  -D__declspec(x)=__attribute__((x)) \
   -Asystem(winnt) -Acpu(i386) -Amachine(i386)"
 
 /* Specific a different directory for the standard include files.  */

gcc/tree.c

@@ -2265,9 +2265,12 @@ staticp (arg)
     case FUNCTION_DECL:
       /* Nested functions aren't static, since taking their address
 	 involves a trampoline.  */
-       return decl_function_context (arg) == 0 || DECL_NO_STATIC_CHAIN (arg);
+       return (decl_function_context (arg) == 0 || DECL_NO_STATIC_CHAIN (arg))
+              && ! DECL_NON_ADDR_CONST_P (arg);
+
     case VAR_DECL:
-      return TREE_STATIC (arg) || DECL_EXTERNAL (arg);
+      return (TREE_STATIC (arg) || DECL_EXTERNAL (arg))
+             && ! DECL_NON_ADDR_CONST_P (arg);
 
     case CONSTRUCTOR:
       return TREE_STATIC (arg);

gcc/tree.h

@@ -1201,6 +1201,10 @@ struct tree_type
 #define DECL_LANG_FLAG_6(NODE) (DECL_CHECK (NODE)->decl.lang_flag_6)
 #define DECL_LANG_FLAG_7(NODE) (DECL_CHECK (NODE)->decl.lang_flag_7)
 
+/* Used to indicate that the pointer to this DECL cannot be treated as
+   an address constant.  */
+#define DECL_NON_ADDR_CONST_P(NODE) (DECL_CHECK (NODE)->decl.non_addr_const_p)
+
 struct tree_decl
 {
   char common[sizeof (struct tree_common)];
@@ -1242,6 +1246,8 @@ struct tree_decl
   unsigned lang_flag_6 : 1;
   unsigned lang_flag_7 : 1;
 
+  unsigned non_addr_const_p : 1;
+
   /* For a FUNCTION_DECL, if inline, this is the size of frame needed.
      If built-in, this is the code for which built-in function.
      For other kinds of decls, this is DECL_ALIGN.  */