Add support for generating unique sections for unitialised data.

From-SVN: r31250

9 files changed, 188 insertions, 69 deletions

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index e99b3d7..b345602 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,37 @@
+2000-01-05  Nick Clifton  <nickc@cygnus.com>
+
+	* varasm.c (IN_NAMED_SECTION): Allow targets to provide their
+	own definition of this macro.
+	(asm_emit_uninitialised): Invoke UNIQUE_SECTION if either
+	flag_data_sections or UNIQUE_SECTION_P are true.
+
+	* tm.texi (UNIQUE)SECTION): Document that it can be called for
+	unitialised data decls.
+
+	* config/i386/winnt.c (i386_pe_unique_section): Cope with
+	being called for uninitialised data.
+
+	* config/i386/interix.c (i386_pe_unique_section): Cope with
+	being called for uninitialised data.
+
+	* config/mips/elf.h (UNIQUE_SECTION): Cope with being called
+	for uninitialised data. 
+
+	* config/mips/elf64.h (UNIQUE_SECTION): Cope with being called
+	for uninitialised data. 
+
+	* config/mips/iri6gld.h (UNIQUE_SECTION): Cope with being called
+	for uninitialised data. 
+
+	* config/arm/unknown-elf.h (IN_NAMED_SECTION): Define.
+	(UNIQUE_SECTION_P): Always generate a unique section if
+	flag_data_sections is true.
+	(UNIQUE_SECTION): Also generate unique sections for
+	uninitialised data.
+	(ASM_OUTPUT_ALIGNED_BSS): Redefine to use named_section().
+	(ASM_OUTPUT_ALIGNED_DECL_LOCAL): Redefine to use
+	named_section(). 
+	
 2000-01-06  Michael Hayes  <m.hayes@elec.canterbury.ac.nz>
 
 	* config/c4x/t-c4x (TARGET_LIBGCC2_CFLAGS): Don't redefine SF, DF,
diff --git a/gcc/config/arm/unknown-elf.h b/gcc/config/arm/unknown-elf.h
index aeddcdf..33bd9af 100644
--- a/gcc/config/arm/unknown-elf.h
+++ b/gcc/config/arm/unknown-elf.h
@@ -122,38 +122,90 @@ do {								\
 #define NAME__MAIN "__gccmain"
 #define SYMBOL__MAIN __gccmain
 
+/* Return a non-zero value if DECL has a section attribute.  */
+#define IN_NAMED_SECTION(DECL)						\
+  ((TREE_CODE (DECL) == FUNCTION_DECL || TREE_CODE (DECL) == VAR_DECL)	\
+   && DECL_SECTION_NAME (DECL) != NULL_TREE)
+
+
 #define MAKE_DECL_ONE_ONLY(DECL) (DECL_WEAK (DECL) = 1)
-#define UNIQUE_SECTION_P(DECL) (DECL_ONE_ONLY (DECL))
-#define UNIQUE_SECTION(DECL,RELOC)				\
-do {								\
-  int len;							\
-  char * name, * string, * prefix;				\
-								\
-  name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (DECL));	\
-								\
-  if (! DECL_ONE_ONLY (DECL))					\
-    {								\
-      prefix = ".";                                             \
-      if (TREE_CODE (DECL) == FUNCTION_DECL)			\
-	prefix = ".text.";					\
-      else if (DECL_READONLY_SECTION (DECL, RELOC))		\
-	prefix = ".rodata.";					\
-      else							\
-	prefix = ".data.";					\
-    }								\
-  else if (TREE_CODE (DECL) == FUNCTION_DECL)			\
-    prefix = ".gnu.linkonce.t.";				\
-  else if (DECL_READONLY_SECTION (DECL, RELOC))			\
-    prefix = ".gnu.linkonce.r.";				\
-  else								\
-    prefix = ".gnu.linkonce.d.";				\
-								\
-  len = strlen (name) + strlen (prefix);			\
-  string = alloca (len + 1);					\
-  sprintf (string, "%s%s", prefix, name);			\
-								\
-  DECL_SECTION_NAME (DECL) = build_string (len, string);	\
-} while (0)
+     
+#define UNIQUE_SECTION_P(DECL) (DECL_ONE_ONLY (DECL) || flag_data_sections)
+     
+#define UNIQUE_SECTION(DECL, RELOC)					\
+  do									\
+    {									\
+      int len;								\
+      int sec;								\
+      char *name;							\
+      char *string;							\
+      char *prefix;							\
+      static char *prefixes[4][2] =					\
+      {									\
+	{ ".text.",   ".gnu.linkonce.t." },				\
+	{ ".rodata.", ".gnu.linkonce.r." },				\
+	{ ".data.",   ".gnu.linkonce.d." },				\
+        { ".bss.",    ".gnu.linkonce.b." }				\
+      };								\
+      									\
+      if (TREE_CODE (DECL) == FUNCTION_DECL)				\
+	sec = 0;							\
+      else if (DECL_INITIAL (DECL) == 0					\
+	       || DECL_INITIAL (DECL) == error_mark_node)		\
+	sec = 3;							\
+      else if (DECL_READONLY_SECTION (DECL, RELOC))			\
+	sec = 1;							\
+      else								\
+	sec = 2;							\
+      									\
+      prefix = prefixes[sec][DECL_ONE_ONLY(DECL)];			\
+      name   = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (DECL));		\
+      									\
+      /* Strip off any encoding in name.  */				\
+      STRIP_NAME_ENCODING (name, name);					\
+									\
+      len    = strlen (name) + strlen (prefix);				\
+      string = alloca (len + 1);					\
+      									\
+      sprintf (string, "%s%s", prefix, name);				\
+      									\
+      DECL_SECTION_NAME (DECL) = build_string (len, string);		\
+    }									\
+  while (0)
+
+#undef  ASM_OUTPUT_ALIGNED_BSS
+#define ASM_OUTPUT_ALIGNED_BSS(FILE, DECL, NAME, SIZE, ALIGN)   	\
+  do									\
+    {									\
+      if (IN_NAMED_SECTION (DECL))					\
+	named_section (DECL, NULL, 0);					\
+      else								\
+	bss_section ();							\
+      									\
+      ASM_GLOBALIZE_LABEL (FILE, NAME);					\
+      									\
+      ASM_OUTPUT_ALIGN (FILE, floor_log2 (ALIGN / BITS_PER_UNIT));	\
+									\
+      last_assemble_variable_decl = DECL;				\
+      ASM_DECLARE_OBJECT_NAME (FILE, NAME, DECL);			\
+      ASM_OUTPUT_SKIP (FILE, SIZE ? SIZE : 1);				\
+    } 									\
+  while (0)
+
+#undef  ASM_OUTPUT_ALIGNED_DECL_LOCAL
+#define ASM_OUTPUT_ALIGNED_DECL_LOCAL(FILE, DECL, NAME, SIZE, ALIGN)	\
+  do									\
+    {									\
+      if (IN_NAMED_SECTION (DECL))					\
+	named_section (DECL, NULL, 0);					\
+      else								\
+	bss_section ();							\
+									\
+      ASM_OUTPUT_ALIGN (FILE, floor_log2 (ALIGN / BITS_PER_UNIT));	\
+      ASM_OUTPUT_LABEL (FILE, NAME);					\
+      fprintf (FILE, "\t.space\t%d\n", SIZE);				\
+    }									\
+  while (0)
 
 #ifndef CPP_APCS_PC_DEFAULT_SPEC
 #define CPP_APCS_PC_DEFAULT_SPEC	"-D__APCS_32__"
diff --git a/gcc/config/i386/interix.c b/gcc/config/i386/interix.c
index 5a2b8b6..4f4f823 100644
--- a/gcc/config/i386/interix.c
+++ b/gcc/config/i386/interix.c
@@ -93,6 +93,9 @@ i386_pe_unique_section (decl, reloc)
      without a .rdata section.  */
   if (TREE_CODE (decl) == FUNCTION_DECL)
     prefix = ".text$";
+  else if (DECL_INITIAL (decl) == 0
+	   || DECL_INITIAL (decl) == error_mark_node)
+    prefix = "";
   else if (DECL_READONLY_SECTION (decl, reloc))
 #ifdef READONLY_DATA_SECTION
     prefix = ".rdata$";
diff --git a/gcc/config/i386/winnt.c b/gcc/config/i386/winnt.c
index 2c2ce76..13701e2 100644
--- a/gcc/config/i386/winnt.c
+++ b/gcc/config/i386/winnt.c
@@ -480,6 +480,9 @@ i386_pe_unique_section (decl, reloc)
      without a .rdata section.  */
   if (TREE_CODE (decl) == FUNCTION_DECL)
     prefix = ".text$";
+  else if (DECL_INITIAL (decl) == 0
+	   || DECL_INITIAL (decl) == error_mark_node)
+    prefix = "";
   else if (DECL_READONLY_SECTION (decl, reloc))
 #ifdef READONLY_DATA_SECTION
     prefix = ".rdata$";
diff --git a/gcc/config/mips/elf.h b/gcc/config/mips/elf.h
index 9299ac8..b265295 100644
--- a/gcc/config/mips/elf.h
+++ b/gcc/config/mips/elf.h
@@ -212,20 +212,24 @@ do {									 \
 do {									   \
   int len, size, sec;							   \
   char *name, *string, *prefix;						   \
-  static char *prefixes[4][2] = {					   \
+  static char *prefixes[5][2] = {					   \
     { ".text.", ".gnu.linkonce.t." },					   \
     { ".rodata.", ".gnu.linkonce.r." },					   \
     { ".data.", ".gnu.linkonce.d." },					   \
-    { ".sdata.", ".gnu.linkonce.s." }					   \
+    { ".sdata.", ".gnu.linkonce.s." },					   \
+    { "", "" }								   \
   };									   \
 									   \
   name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (DECL));		   \
   size = int_size_in_bytes (TREE_TYPE (decl));				   \
 									   \
   /* Determine the base section we are interested in:			   \
-     0=text, 1=rodata, 2=data, 3=sdata.  */				   \
+     0=text, 1=rodata, 2=data, 3=sdata, [4=bss].  */			   \
   if (TREE_CODE (DECL) == FUNCTION_DECL)				   \
     sec = 0;								   \
+  else if (DECL_INITIAL (DECL) == 0					   \
+           || DECL_INITIAL (DECL) == error_mark_node)			   \
+    sec = 4;								   \
   else if ((TARGET_EMBEDDED_PIC || TARGET_MIPS16)			   \
       && TREE_CODE (decl) == STRING_CST					   \
       && !flag_writable_strings)					   \
diff --git a/gcc/config/mips/elf64.h b/gcc/config/mips/elf64.h
index 5d6632e..907e4cb 100644
--- a/gcc/config/mips/elf64.h
+++ b/gcc/config/mips/elf64.h
@@ -197,16 +197,20 @@ do {									   \
     { ".text.", ".gnu.linkonce.t." },					   \
     { ".rodata.", ".gnu.linkonce.r." },					   \
     { ".data.", ".gnu.linkonce.d." },					   \
-    { ".sdata.", ".gnu.linkonce.s." }					   \
+    { ".sdata.", ".gnu.linkonce.s." },					   \
+    { "", "" }								   \
   };									   \
 									   \
   name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (DECL));		   \
   size = int_size_in_bytes (TREE_TYPE (decl));				   \
 									   \
   /* Determine the base section we are interested in:			   \
-     0=text, 1=rodata, 2=data, 3=sdata.  */				   \
+     0=text, 1=rodata, 2=data, 3=sdata, [4=bss].  */			   \
   if (TREE_CODE (DECL) == FUNCTION_DECL)				   \
     sec = 0;								   \
+  else if (DECL_INITIAL (DECL) == 0					   \
+           || DECL_INITIAL (DECL) == error_mark_node)			   \
+    sec = 4;								   \
   else if ((TARGET_EMBEDDED_PIC || TARGET_MIPS16)			   \
       && TREE_CODE (decl) == STRING_CST					   \
       && !flag_writable_strings)					   \
diff --git a/gcc/config/mips/iris6gld.h b/gcc/config/mips/iris6gld.h
index 860733f..1424021 100644
--- a/gcc/config/mips/iris6gld.h
+++ b/gcc/config/mips/iris6gld.h
@@ -49,35 +49,45 @@ Boston, MA 02111-1307, USA.  */
 
 /* The GNU linker supports one-only sections.  */
 #define MAKE_DECL_ONE_ONLY(DECL) (DECL_WEAK (DECL) = 1)
-#undef UNIQUE_SECTION_P
+#undef  UNIQUE_SECTION_P
 #define UNIQUE_SECTION_P(DECL) (DECL_ONE_ONLY (DECL))
-#define UNIQUE_SECTION(DECL,RELOC)				\
-do {								\
-  int len;							\
-  char *name, *string, *prefix;					\
-								\
-  name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (DECL));	\
-								\
-  if (! DECL_ONE_ONLY (DECL))					\
+#define UNIQUE_SECTION(DECL, RELOC)				\
+  do								\
     {								\
-      prefix = ".";                                             \
+      int len;							\
+      int sec;							\
+      char *name;						\
+      char *string;						\
+      char *prefix;						\
+      static char *prefixes[4][2] =				\
+      {								\
+	{ ".text.",   ".gnu.linkonce.t." },			\
+	{ ".rodata.", ".gnu.linkonce.r." },			\
+	{ ".data.",   ".gnu.linkonce.d." },			\
+	/* Do not generate unique sections for uninitialised 	\
+	   data since we do not have support for this in the    \
+	   linker scripts yet...				\
+        { ".bss.",    ".gnu.linkonce.b." }  */			\
+	{ "", "" }						\
+      };							\
+      								\
       if (TREE_CODE (DECL) == FUNCTION_DECL)			\
-	prefix = ".text.";					\
+	sec = 0;						\
+      else if (DECL_INITIAL (DECL) == 0				\
+	       || DECL_INITIAL (DECL) == error_mark_node)	\
+	sec = 3;						\
       else if (DECL_READONLY_SECTION (DECL, RELOC))		\
-	prefix = ".rodata.";					\
+	sec = 1;						\
       else							\
-	prefix = ".data.";					\
+	sec = 2;						\
+      								\
+      name   = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (DECL));	\
+      prefix = prefixes[sec][DECL_ONE_ONLY(DECL)];		\
+      len    = strlen (name) + strlen (prefix);			\
+      string = alloca (len + 1);				\
+      								\
+      sprintf (string, "%s%s", prefix, name);			\
+      								\
+      DECL_SECTION_NAME (DECL) = build_string (len, string);	\
     }								\
-  else if (TREE_CODE (DECL) == FUNCTION_DECL)			\
-    prefix = ".gnu.linkonce.t.";				\
-  else if (DECL_READONLY_SECTION (DECL, RELOC))			\
-    prefix = ".gnu.linkonce.r.";				\
-  else								\
-    prefix = ".gnu.linkonce.d.";				\
-								\
-  len = strlen (name) + strlen (prefix);			\
-  string = alloca (len + 1);					\
-  sprintf (string, "%s%s", prefix, name);			\
-								\
-  DECL_SECTION_NAME (DECL) = build_string (len, string);	\
-} while (0)
+  while (0)
diff --git a/gcc/tm.texi b/gcc/tm.texi
index 6a3ff51..b2d43c9 100644
--- a/gcc/tm.texi
+++ b/gcc/tm.texi
@@ -4999,7 +4999,9 @@ A C statement to build up a unique section name, expressed as a
 STRING_CST node, and assign it to @samp{DECL_SECTION_NAME (@var{decl})}.
 @var{reloc} indicates whether the initial value of @var{exp} requires
 link-time relocations.  If you do not define this macro, GCC will use
-the symbol name prefixed by @samp{.} as the section name.
+the symbol name prefixed by @samp{.} as the section name.  Note - this
+macro can now be called for unitialised data items as well as
+initialised data and functions.
 @end table
 
 @node PIC
@@ -5513,7 +5515,6 @@ in place of both @code{ASM_OUTPUT_DECL} and
 @code{ASM_OUTPUT_ALIGNED_DECL}.  Define this macro when you need to see
 the variable's decl in order to chose what to output.
 
-
 @findex ASM_OUTPUT_SHARED_LOCAL
 @item ASM_OUTPUT_SHARED_LOCAL (@var{stream}, @var{name}, @var{size}, @var{rounded})
 If defined, it is similar to @code{ASM_OUTPUT_LOCAL}, except that it
diff --git a/gcc/varasm.c b/gcc/varasm.c
index 6087c7b..2743abe 100644
--- a/gcc/varasm.c
+++ b/gcc/varasm.c
@@ -202,10 +202,12 @@ static enum in_section { no_section, in_text, in_data, in_named
 } in_section = no_section;
 
 /* Return a non-zero value if DECL has a section attribute.  */
+#ifndef IN_NAMED_SECTION
 #define IN_NAMED_SECTION(DECL) \
   ((TREE_CODE (DECL) == FUNCTION_DECL || TREE_CODE (DECL) == VAR_DECL) \
    && DECL_SECTION_NAME (DECL) != NULL_TREE)
-
+#endif
+     
 /* Text of section name when in_section == in_named.  */
 static char *in_named_name;
 
@@ -1233,7 +1235,8 @@ asm_emit_uninitialised (decl, name, size, rounded)
      int size;
      int rounded ATTRIBUTE_UNUSED;
 {
-  enum {
+  enum
+  {
     asm_dest_common,
     asm_dest_bss,
     asm_dest_local
@@ -1274,6 +1277,12 @@ asm_emit_uninitialised (decl, name, size, rounded)
 	}
     }
 
+#ifdef ASM_OUTPUT_SECTION_NAME
+  /* We already know that DECL_SECTION_NAME() == NULL.  */
+  if (flag_data_sections != 0 || UNIQUE_SECTION_P (decl))
+    UNIQUE_SECTION (decl, NULL);
+#endif
+  
   switch (destination)
     {
 #ifdef ASM_EMIT_BSS
@@ -1486,7 +1495,7 @@ assemble_variable (decl, top_level, at_end, dont_output_data)
 #if ! defined ASM_EMIT_BSS
       && DECL_COMMON (decl)
 #endif
-      && DECL_SECTION_NAME (decl) == 0
+      && DECL_SECTION_NAME (decl) == NULL_TREE
       && ! dont_output_data)
     {
       int size = TREE_INT_CST_LOW (size_tree);
@@ -1575,8 +1584,7 @@ assemble_variable (decl, top_level, at_end, dont_output_data)
     reloc = output_addressed_constants (DECL_INITIAL (decl));
 
 #ifdef ASM_OUTPUT_SECTION_NAME
-  if ((flag_data_sections != 0
-       && DECL_SECTION_NAME (decl) == NULL_TREE)
+  if ((flag_data_sections != 0 && DECL_SECTION_NAME (decl) == NULL_TREE)
       || UNIQUE_SECTION_P (decl))
     UNIQUE_SECTION (decl, reloc);
 #endif