[6/10] RFC: fix somread.c

[Tom Tromey <tromey at redhat dot com>]

CCing binutils because this needed a small BFD change.  I needed to be
able to call bfd_section_from_som_symbol from gdb, so I changed it to be
non-static and declared it in bfd/som.h.

One problem with unifying 'section' and 'obj_section' is that the
somread code uses hard-coded section indices.  This was filed in
bugzilla ages ago: http://sourceware.org/bugzilla/show_bug.cgi?id=8423

This patch reworks all this code to use the BFD section indices.

Tom

BFD:
	* som.c (bfd_section_from_som_symbol): No longer static.
	* som.h (bfd_section_from_som_symbol): Declare.

gdb:
	PR symtab/8423:
	* solib-som.c (som_solib_section_offsets): Use BFD section
	indices.  Set offsets for all sections.
	* somread.c (som_symtab_read): Compute BFD section for
	symbol.  Use prim_record_minimal_symbol_and_info.
	(som_symfile_read): Fix comment.
	(struct find_section_offset_arg): New.
	(find_section_offset, set_section_index): New functions.
	(som_symfile_offsets): Use set_section_index to compute
	section indices.
---
 bfd/som.c       |    4 +-
 bfd/som.h       |    3 +-
 gdb/solib-som.c |   29 ++++++++--
 gdb/somread.c   |  151 +++++++++++++++++++++++++++++++++++++++++++++++++------
 4 files changed, 163 insertions(+), 24 deletions(-)

diff --git a/bfd/som.c b/bfd/som.c
index 87aa88f..0ddbb6f 100644
--- a/bfd/som.c
+++ b/bfd/som.c
@@ -1,7 +1,7 @@
 /* bfd back-end for HP PA-RISC SOM objects.
    Copyright 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999,
    2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011,
-   2012  Free Software Foundation, Inc.
+   2012, 2013  Free Software Foundation, Inc.
 
    Contributed by the Center for Software Science at the
    University of Utah.
@@ -4572,7 +4572,7 @@ som_get_symtab_upper_bound (bfd *abfd)
 
 /* Convert from a SOM subspace index to a BFD section.  */
 
-static asection *
+asection *
 bfd_section_from_som_symbol
   (bfd *abfd, struct som_external_symbol_dictionary_record *symbol)
 {
diff --git a/bfd/som.h b/bfd/som.h
index cf8dcbf..7a54249 100644
--- a/bfd/som.h
+++ b/bfd/som.h
@@ -1,6 +1,6 @@
 /* HP PA-RISC SOM object file format:  definitions internal to BFD.
    Copyright 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1998, 2000, 2001,
-   2002, 2003, 2004, 2005, 2007, 2008, 2012 Free Software Foundation, Inc.
+   2002, 2003, 2004, 2005, 2007, 2008, 2012, 2013 Free Software Foundation, Inc.
 
    Contributed by the Center for Software Science at the
    University of Utah (pa-gdb-bugs@cs.utah.edu).
@@ -234,5 +234,6 @@ void         bfd_som_set_symbol_type           (asymbol *, unsigned int);
 bfd_boolean  bfd_som_attach_aux_hdr            (bfd *, int, char *);
 int **       hppa_som_gen_reloc_type           (bfd *, int, int, enum hppa_reloc_field_selector_type_alt, int, asymbol *);
 bfd_boolean  bfd_som_attach_compilation_unit   (bfd *, const char *, const char *, const char *, const char *);
+asection *   bfd_section_from_som_symbol       (bfd *abfd, struct som_external_symbol_dictionary_record *symbol);
 
 #endif /* _SOM_H */
diff --git a/gdb/solib-som.c b/gdb/solib-som.c
index bd763b8..3bf78e2 100644
--- a/gdb/solib-som.c
+++ b/gdb/solib-som.c
@@ -840,13 +840,12 @@ som_solib_section_offsets (struct objfile *objfile,
       if (strstr (objfile->name, so_list->so_name))
 	{
 	  asection *private_section;
+	  struct obj_section *sect;
 
 	  /* The text offset is easy.  */
 	  offsets->offsets[SECT_OFF_TEXT (objfile)]
 	    = (so_list->lm_info->text_addr
 	       - so_list->lm_info->text_link_addr);
-	  offsets->offsets[SECT_OFF_RODATA (objfile)]
-	    = ANOFFSET (offsets, SECT_OFF_TEXT (objfile));
 
 	  /* We should look at presumed_dp in the SOM header, but
 	     that's not easily available.  This should be OK though.  */
@@ -859,10 +858,28 @@ som_solib_section_offsets (struct objfile *objfile,
 	      offsets->offsets[SECT_OFF_BSS (objfile)] = 0;
 	      return 1;
 	    }
-	  offsets->offsets[SECT_OFF_DATA (objfile)]
-	    = (so_list->lm_info->data_start - private_section->vma);
-	  offsets->offsets[SECT_OFF_BSS (objfile)]
-	    = ANOFFSET (offsets, SECT_OFF_DATA (objfile));
+	  if (objfile->sect_index_data != -1)
+	    {
+	      offsets->offsets[SECT_OFF_DATA (objfile)]
+		= (so_list->lm_info->data_start - private_section->vma);
+	      if (objfile->sect_index_bss != -1)
+		offsets->offsets[SECT_OFF_BSS (objfile)]
+		  = ANOFFSET (offsets, SECT_OFF_DATA (objfile));
+	    }
+
+	  ALL_OBJFILE_OSECTIONS (objfile, sect)
+	    {
+	      flagword flags = bfd_get_section_flags (objfile->obfd,
+						      sect->the_bfd_section);
+
+	      if ((flags & SEC_CODE) != 0)
+		offsets->offsets[sect->the_bfd_section->index]
+		  = offsets->offsets[SECT_OFF_TEXT (objfile)];
+	      else
+		offsets->offsets[sect->the_bfd_section->index]
+		  = offsets->offsets[SECT_OFF_DATA (objfile)];
+	    }
+
 	  return 1;
 	}
       so_list = so_list->next;
diff --git a/gdb/somread.c b/gdb/somread.c
index d9d3e7b..858574f 100644
--- a/gdb/somread.c
+++ b/gdb/somread.c
@@ -54,11 +54,10 @@ som_symtab_read (bfd *abfd, struct objfile *objfile,
   struct som_external_symbol_dictionary_record *buf, *bufp, *endbufp;
   char *symname;
   CONST int symsize = sizeof (struct som_external_symbol_dictionary_record);
-  CORE_ADDR text_offset, data_offset;
 
 
-  text_offset = ANOFFSET (section_offsets, 0);
-  data_offset = ANOFFSET (section_offsets, 1);
+#define text_offset ANOFFSET (section_offsets, SECT_OFF_TEXT (objfile))
+#define data_offset ANOFFSET (section_offsets, SECT_OFF_DATA (objfile))
 
   number_of_symbols = bfd_get_symcount (abfd);
 
@@ -106,9 +105,36 @@ som_symtab_read (bfd *abfd, struct objfile *objfile,
       unsigned int symbol_scope
 	= (flags >> SOM_SYMBOL_SCOPE_SH) & SOM_SYMBOL_SCOPE_MASK;
       CORE_ADDR symbol_value = bfd_getb32 (bufp->symbol_value);
+      asection *section = NULL;
 
       QUIT;
 
+      /* Compute the section.  */
+      switch (symbol_scope)
+	{
+	case SS_EXTERNAL:
+	  if (symbol_type != ST_STORAGE)
+	    section = bfd_und_section_ptr;
+	  else
+	    section = bfd_com_section_ptr;
+	  break;
+
+	case SS_UNSAT:
+	  if (symbol_type != ST_STORAGE)
+	    section = bfd_und_section_ptr;
+	  else
+	    section = bfd_com_section_ptr;
+	  break;
+
+	case SS_UNIVERSAL:
+	  section = bfd_section_from_som_symbol (abfd, bufp);
+	  break;
+
+	case SS_LOCAL:
+	  section = bfd_section_from_som_symbol (abfd, bufp);
+	  break;
+	}
+
       switch (symbol_scope)
 	{
 	case SS_UNIVERSAL:
@@ -267,7 +293,29 @@ som_symtab_read (bfd *abfd, struct objfile *objfile,
 	error (_("Invalid symbol data; bad HP string table offset: %s"),
 	       plongest (bfd_getb32 (bufp->name)));
 
-      prim_record_minimal_symbol (symname, symbol_value, ms_type, objfile);
+      if (bfd_is_const_section (section))
+	{
+	  struct obj_section *iter;
+
+	  ALL_OBJFILE_OSECTIONS (objfile, iter)
+	    {
+	      if (bfd_is_const_section (iter->the_bfd_section))
+		continue;
+
+	      if (obj_section_addr (iter) <= symbol_value
+		  && symbol_value < obj_section_endaddr (iter))
+		{
+		  section = iter->the_bfd_section;
+		  break;
+		}
+	    }
+	}
+
+      prim_record_minimal_symbol_and_info (symname, symbol_value, ms_type,
+					   gdb_bfd_section_index (objfile->obfd,
+								  section),
+					   section,
+					   objfile);
     }
 }
 
@@ -287,7 +335,7 @@ som_symtab_read (bfd *abfd, struct objfile *objfile,
    for real.
 
    We look for sections with specific names, to tell us what debug
-   format to look for:  FIXME!!!
+   format to look for.
 
    somstab_build_psymtabs() handles STABS symbols.
 
@@ -361,6 +409,80 @@ som_symfile_init (struct objfile *objfile)
   objfile->flags |= OBJF_REORDERED;
 }
 
+/* An object of this type is passed to find_section_offset.  */
+
+struct find_section_offset_arg
+{
+  /* The objfile.  */
+
+  struct objfile *objfile;
+
+  /* Flags to invert.  */
+
+  flagword invert;
+
+  /* Flags to look for.  */
+
+  flagword flags;
+
+  /* A text section with non-zero size, if any.  */
+
+  asection *best_section;
+
+  /* An empty text section, if any.  */
+
+  asection *empty_section;
+};
+
+/* A callback for bfd_map_over_sections that tries to find a section
+   with particular flags in an objfile.  */
+
+static void
+find_section_offset (bfd *abfd, asection *sect, void *arg)
+{
+  struct find_section_offset_arg *info = arg;
+  flagword aflag;
+
+  aflag = bfd_get_section_flags (abfd, sect);
+
+  aflag ^= info->invert;
+
+  if ((aflag & info->flags) == info->flags)
+    {
+      if (bfd_section_size (abfd, sect) > 0)
+	{
+	  if (info->best_section == NULL)
+	    info->best_section = sect;
+	}
+      else
+	{
+	  if (info->empty_section == NULL)
+	    info->empty_section = sect;
+	}
+    }
+}
+
+/* Set a section index from a BFD.  */
+
+static void
+set_section_index (struct objfile *objfile, flagword invert, flagword flags,
+		   int *index_ptr)
+{
+  struct find_section_offset_arg info;
+
+  info.objfile = objfile;
+  info.best_section = NULL;
+  info.empty_section = NULL;
+  info.invert = invert;
+  info.flags = flags;
+  bfd_map_over_sections (objfile->obfd, find_section_offset, &info);
+
+  if (info.best_section)
+    *index_ptr = info.best_section->index;
+  else if (info.empty_section)
+    *index_ptr = info.empty_section->index;
+}
+
 /* SOM specific parsing routine for section offsets.
 
    Plain and simple for now.  */
@@ -370,22 +492,21 @@ som_symfile_offsets (struct objfile *objfile, struct section_addr_info *addrs)
 {
   int i;
   CORE_ADDR text_addr;
+  asection *sect;
 
   objfile->num_sections = bfd_count_sections (objfile->obfd);
   objfile->section_offsets = (struct section_offsets *)
     obstack_alloc (&objfile->objfile_obstack, 
 		   SIZEOF_N_SECTION_OFFSETS (objfile->num_sections));
 
-  /* FIXME: ezannoni 2000-04-20 The section names in SOM are not
-     .text, .data, etc, but $TEXT$, $DATA$,...  We should initialize
-     SET_OFF_* from bfd.  (See default_symfile_offsets()).  But I don't
-     know the correspondence between SOM sections and GDB's idea of
-     section names.  So for now we default to what is was before these
-     changes.  */
-  objfile->sect_index_text = 0;
-  objfile->sect_index_data = 1;
-  objfile->sect_index_bss = 2;
-  objfile->sect_index_rodata = 3;
+  set_section_index (objfile, 0, SEC_ALLOC | SEC_CODE,
+		     &objfile->sect_index_text);
+  set_section_index (objfile, 0, SEC_ALLOC | SEC_DATA,
+		     &objfile->sect_index_data);
+  set_section_index (objfile, SEC_LOAD, SEC_ALLOC | SEC_LOAD,
+		     &objfile->sect_index_bss);
+  set_section_index (objfile, 0, SEC_ALLOC | SEC_READONLY,
+		     &objfile->sect_index_rodata);
 
   /* First see if we're a shared library.  If so, get the section
      offsets from the library, else get them from addrs.  */
-- 
1.7.7.6