Change representation of psymbol to flush out accessors

This is the psymbol analog to the patch to change the representation
of minimal symbols:

    https://sourceware.org/ml/gdb-patches/2013-10/msg00524.html

It has the same rationale: namely, that we're going to change the code
to apply psymbol offsets at runtime.  This will be done by adding an
argument to the SYMBOL_VALUE_ADDRESS macro -- but since we can't
convert all the symbol types at once, we need a new approach.

Because gdb now is in C++, this patch changes partial_symbol to
inherit from general_symbol_info, rather than renaming the field.
This simplifies code in some places.

Also, as noted before, these macros implement a kind of "phony
polymorphism" that is not actually useful in practice; so this patch
removes the macros in favor of simply referring directly to members.
In a few cases -- obj_section in this patch and the symbol address in
the future -- methods will be used instead.

Note that this removes the blanket memset from add_psymbol_to_bcache.
This hasn't really been needed since bcache was modified to allow
holes in objects and since psymtab took advantage of that.  This
deletion was required due to changing partial_symbol to derive from
general_symbol_info.

gdb/ChangeLog
2018-07-26  Tom Tromey  <tom@tromey.com>

	* dwarf-index-write.c (write_psymbols, debug_names::insert)
	(debug_names::write_psymbols): Update.
	* psympriv.h (struct partial_symbol): Derive from
	general_symbol_info.
	<obj_section>: New method.
	(PSYMBOL_DOMAIN, PSYMBOL_CLASS): Remove.n
	* psymtab.c (find_pc_sect_psymtab_closer, find_pc_sect_psymtab)
	(find_pc_sect_psymbol, fixup_psymbol_section)
	(match_partial_symbol, lookup_partial_symbol, relocate_psymtabs)
	(print_partial_symbols, recursively_search_psymtabs)
	(compare_psymbols, psymbol_hash, psymbol_compare)
	(add_psymbol_to_bcache, maintenance_check_psymtabs)
	(psymbol_name_matches, psym_fill_psymbol_map): Update.

1 files changed, 82 insertions, 86 deletions

diff --git a/gdb/psymtab.c b/gdb/psymtab.c
index fa59ee2..9a06d68 100644
--- a/gdb/psymtab.c
+++ b/gdb/psymtab.c
@@ -267,8 +267,7 @@ find_pc_sect_psymtab_closer (struct objfile *objfile,
 	     object's symbol table.  */
 	  p = find_pc_sect_psymbol (objfile, tpst, pc, section);
 	  if (p != NULL
-	      && (SYMBOL_VALUE_ADDRESS (p)
-		  == BMSYMBOL_VALUE_ADDRESS (msymbol)))
+	      && (p->value.address == BMSYMBOL_VALUE_ADDRESS (msymbol)))
 	    return tpst;
 
 	  /* Also accept the textlow value of a psymtab as a
@@ -276,7 +275,7 @@ find_pc_sect_psymtab_closer (struct objfile *objfile,
 	     symbol tables with line information but no debug
 	     symbols (e.g. those produced by an assembler).  */
 	  if (p != NULL)
-	    this_addr = SYMBOL_VALUE_ADDRESS (p);
+	    this_addr = p->value.address;
 	  else
 	    this_addr = tpst->textlow;
 
@@ -334,8 +333,7 @@ find_pc_sect_psymtab (struct objfile *objfile, CORE_ADDR pc,
 		 object's symbol table.  */
 	      p = find_pc_sect_psymbol (objfile, pst, pc, section);
 	      if (p == NULL
-		  || (SYMBOL_VALUE_ADDRESS (p)
-		      != BMSYMBOL_VALUE_ADDRESS (msymbol)))
+		  || (p->value.address != BMSYMBOL_VALUE_ADDRESS (msymbol)))
 		goto next;
 	    }
 
@@ -425,21 +423,21 @@ find_pc_sect_psymbol (struct objfile *objfile,
     {
       partial_symbol *p = objfile->global_psymbols[psymtab->globals_offset + i];
 
-      if (SYMBOL_DOMAIN (p) == VAR_DOMAIN
-	  && PSYMBOL_CLASS (p) == LOC_BLOCK
-	  && pc >= SYMBOL_VALUE_ADDRESS (p)
-	  && (SYMBOL_VALUE_ADDRESS (p) > best_pc
+      if (p->domain == VAR_DOMAIN
+	  && p->aclass == LOC_BLOCK
+	  && pc >= p->value.address
+	  && (p->value.address > best_pc
 	      || (psymtab->textlow == 0
-		  && best_pc == 0 && SYMBOL_VALUE_ADDRESS (p) == 0)))
+		  && best_pc == 0 && p->value.address == 0)))
 	{
 	  if (section != NULL)  /* Match on a specific section.  */
 	    {
 	      fixup_psymbol_section (p, objfile);
-	      if (!matching_obj_sections (SYMBOL_OBJ_SECTION (objfile, p),
+	      if (!matching_obj_sections (p->obj_section (objfile),
 					  section))
 		continue;
 	    }
-	  best_pc = SYMBOL_VALUE_ADDRESS (p);
+	  best_pc = p->value.address;
 	  best = p;
 	}
     }
@@ -448,21 +446,21 @@ find_pc_sect_psymbol (struct objfile *objfile,
     {
       partial_symbol *p = objfile->static_psymbols[psymtab->statics_offset + i];
 
-      if (SYMBOL_DOMAIN (p) == VAR_DOMAIN
-	  && PSYMBOL_CLASS (p) == LOC_BLOCK
-	  && pc >= SYMBOL_VALUE_ADDRESS (p)
-	  && (SYMBOL_VALUE_ADDRESS (p) > best_pc
+      if (p->domain == VAR_DOMAIN
+	  && p->aclass == LOC_BLOCK
+	  && pc >= p->value.address
+	  && (p->value.address > best_pc
 	      || (psymtab->textlow == 0
-		  && best_pc == 0 && SYMBOL_VALUE_ADDRESS (p) == 0)))
+		  && best_pc == 0 && p->value.address == 0)))
 	{
 	  if (section != NULL)  /* Match on a specific section.  */
 	    {
 	      fixup_psymbol_section (p, objfile);
-	      if (!matching_obj_sections (SYMBOL_OBJ_SECTION (objfile, p),
+	      if (!matching_obj_sections (p->obj_section (objfile),
 					  section))
 		continue;
 	    }
-	  best_pc = SYMBOL_VALUE_ADDRESS (p);
+	  best_pc = p->value.address;
 	  best = p;
 	}
     }
@@ -478,17 +476,17 @@ fixup_psymbol_section (struct partial_symbol *psym, struct objfile *objfile)
   if (psym == NULL)
     return;
 
-  if (SYMBOL_SECTION (psym) >= 0)
+  if (psym->section >= 0)
     return;
 
   gdb_assert (objfile);
 
-  switch (PSYMBOL_CLASS (psym))
+  switch (psym->aclass)
     {
     case LOC_STATIC:
     case LOC_LABEL:
     case LOC_BLOCK:
-      addr = SYMBOL_VALUE_ADDRESS (psym);
+      addr = psym->value.address;
       break;
     default:
       /* Nothing else will be listed in the minsyms -- no use looking
@@ -496,7 +494,7 @@ fixup_psymbol_section (struct partial_symbol *psym, struct objfile *objfile)
       return;
     }
 
-  fixup_section (&psym->ginfo, addr, objfile);
+  fixup_section (psym, addr, objfile);
 }
 
 /* Psymtab version of lookup_symbol.  See its definition in
@@ -554,10 +552,10 @@ static bool
 psymbol_name_matches (partial_symbol *psym,
 		      const lookup_name_info &lookup_name)
 {
-  const language_defn *lang = language_def (SYMBOL_LANGUAGE (psym));
+  const language_defn *lang = language_def (psym->language);
   symbol_name_matcher_ftype *name_match
     = get_symbol_name_matcher (lang, lookup_name);
-  return name_match (SYMBOL_SEARCH_NAME (psym), lookup_name, NULL);
+  return name_match (symbol_search_name (psym), lookup_name, NULL);
 }
 
 /* Look in PST for a symbol in DOMAIN whose name matches NAME.  Search
@@ -607,11 +605,11 @@ match_partial_symbol (struct objfile *objfile,
 	  center = bottom + (top - bottom) / 2;
 	  gdb_assert (center < top);
 
-	  enum language lang = SYMBOL_LANGUAGE (*center);
+	  enum language lang = (*center)->language;
 	  const char *lang_ln
 	    = lookup_name.language_lookup_name (lang).c_str ();
 
-	  if (ordered_compare (SYMBOL_SEARCH_NAME (*center), lang_ln) >= 0)
+	  if (ordered_compare (symbol_search_name (*center), lang_ln) >= 0)
 	    top = center;
 	  else
 	    bottom = center + 1;
@@ -621,8 +619,8 @@ match_partial_symbol (struct objfile *objfile,
       while (top <= real_top
 	     && psymbol_name_matches (*top, lookup_name))
 	{
-	  if (symbol_matches_domain (SYMBOL_LANGUAGE (*top),
-				     SYMBOL_DOMAIN (*top), domain))
+	  if (symbol_matches_domain ((*top)->language,
+				     (*top)->domain, domain))
 	    return *top;
 	  top++;
 	}
@@ -635,8 +633,8 @@ match_partial_symbol (struct objfile *objfile,
     {
       for (psym = start; psym < start + length; psym++)
 	{
-	  if (symbol_matches_domain (SYMBOL_LANGUAGE (*psym),
-				     SYMBOL_DOMAIN (*psym), domain)
+	  if (symbol_matches_domain ((*psym)->language,
+				     (*psym)->domain, domain)
 	      && psymbol_name_matches (*psym, lookup_name))
 	    return *psym;
 	}
@@ -718,7 +716,7 @@ lookup_partial_symbol (struct objfile *objfile,
 	  if (!(center < top))
 	    internal_error (__FILE__, __LINE__,
 			    _("failed internal consistency check"));
-	  if (strcmp_iw_ordered (SYMBOL_SEARCH_NAME (*center),
+	  if (strcmp_iw_ordered (symbol_search_name (*center),
 				 search_name.get ()) >= 0)
 	    {
 	      top = center;
@@ -734,16 +732,16 @@ lookup_partial_symbol (struct objfile *objfile,
 
       /* For `case_sensitivity == case_sensitive_off' strcmp_iw_ordered will
 	 search more exactly than what matches SYMBOL_MATCHES_SEARCH_NAME.  */
-      while (top >= start && SYMBOL_MATCHES_SEARCH_NAME (*top, lookup_name))
+      while (top >= start && symbol_matches_search_name (*top, lookup_name))
 	top--;
 
       /* Fixup to have a symbol which matches SYMBOL_MATCHES_SEARCH_NAME.  */
       top++;
 
-      while (top <= real_top && SYMBOL_MATCHES_SEARCH_NAME (*top, lookup_name))
+      while (top <= real_top && symbol_matches_search_name (*top, lookup_name))
 	{
-	  if (symbol_matches_domain (SYMBOL_LANGUAGE (*top),
-				     SYMBOL_DOMAIN (*top), domain))
+	  if (symbol_matches_domain ((*top)->language,
+				     (*top)->domain, domain))
 	    return *top;
 	  top++;
 	}
@@ -756,9 +754,9 @@ lookup_partial_symbol (struct objfile *objfile,
     {
       for (psym = start; psym < start + length; psym++)
 	{
-	  if (symbol_matches_domain (SYMBOL_LANGUAGE (*psym),
-				     SYMBOL_DOMAIN (*psym), domain)
-	      && SYMBOL_MATCHES_SEARCH_NAME (*psym, lookup_name))
+	  if (symbol_matches_domain ((*psym)->language,
+				     (*psym)->domain, domain)
+	      && symbol_matches_search_name (*psym, lookup_name))
 	    return *psym;
 	}
     }
@@ -814,14 +812,14 @@ psym_relocate (struct objfile *objfile,
   for (partial_symbol *psym : objfile->global_psymbols)
     {
       fixup_psymbol_section (psym, objfile);
-      if (SYMBOL_SECTION (psym) >= 0)
-	SYMBOL_VALUE_ADDRESS (psym) += ANOFFSET (delta, SYMBOL_SECTION (psym));
+      if (psym->section >= 0)
+	psym->value.address += ANOFFSET (delta, psym->section);
     }
   for (partial_symbol *psym : objfile->static_psymbols)
     {
       fixup_psymbol_section (psym, objfile);
-      if (SYMBOL_SECTION (psym) >= 0)
-	SYMBOL_VALUE_ADDRESS (psym) += ANOFFSET (delta, SYMBOL_SECTION (psym));
+      if (psym->section >= 0)
+	psym->value.address += ANOFFSET (delta, psym->section);
     }
 
   objfile->psymbol_map.clear ();
@@ -893,13 +891,13 @@ print_partial_symbols (struct gdbarch *gdbarch,
   while (count-- > 0)
     {
       QUIT;
-      fprintf_filtered (outfile, "    `%s'", SYMBOL_LINKAGE_NAME (*p));
-      if (SYMBOL_DEMANGLED_NAME (*p) != NULL)
+      fprintf_filtered (outfile, "    `%s'", (*p)->name);
+      if (symbol_demangled_name (*p) != NULL)
 	{
-	  fprintf_filtered (outfile, "  `%s'", SYMBOL_DEMANGLED_NAME (*p));
+	  fprintf_filtered (outfile, "  `%s'", symbol_demangled_name (*p));
 	}
       fputs_filtered (", ", outfile);
-      switch (SYMBOL_DOMAIN (*p))
+      switch ((*p)->domain)
 	{
 	case UNDEF_DOMAIN:
 	  fputs_filtered ("undefined domain, ", outfile);
@@ -917,7 +915,7 @@ print_partial_symbols (struct gdbarch *gdbarch,
 	  fputs_filtered ("<invalid domain>, ", outfile);
 	  break;
 	}
-      switch (PSYMBOL_CLASS (*p))
+      switch ((*p)->aclass)
 	{
 	case LOC_UNDEF:
 	  fputs_filtered ("undefined", outfile);
@@ -969,7 +967,7 @@ print_partial_symbols (struct gdbarch *gdbarch,
 	  break;
 	}
       fputs_filtered (", ", outfile);
-      fputs_filtered (paddress (gdbarch, SYMBOL_VALUE_ADDRESS (*p)), outfile);
+      fputs_filtered (paddress (gdbarch, (*p)->value.address), outfile);
       fprintf_filtered (outfile, "\n");
       p++;
     }
@@ -1364,14 +1362,14 @@ recursively_search_psymtabs
 
 	  if ((domain == ALL_DOMAIN
 	       || (domain == VARIABLES_DOMAIN
-		   && PSYMBOL_CLASS (*psym) != LOC_TYPEDEF
-		   && PSYMBOL_CLASS (*psym) != LOC_BLOCK)
+		   && (*psym)->aclass != LOC_TYPEDEF
+		   && (*psym)->aclass != LOC_BLOCK)
 	       || (domain == FUNCTIONS_DOMAIN
-		   && PSYMBOL_CLASS (*psym) == LOC_BLOCK)
+		   && (*psym)->aclass == LOC_BLOCK)
 	       || (domain == TYPES_DOMAIN
-		   && PSYMBOL_CLASS (*psym) == LOC_TYPEDEF))
+		   && (*psym)->aclass == LOC_TYPEDEF))
 	      && psymbol_name_matches (*psym, lookup_name)
-	      && (sym_matcher == NULL || sym_matcher (SYMBOL_SEARCH_NAME (*psym))))
+	      && (sym_matcher == NULL || sym_matcher (symbol_search_name (*psym))))
 	    {
 	      /* Found a match, so notify our caller.  */
 	      result = PST_SEARCHED_AND_FOUND;
@@ -1475,9 +1473,9 @@ psym_fill_psymbol_map (struct objfile *objfile,
     {
       struct partial_symbol *psym = symbols[start + i];
 
-      if (PSYMBOL_CLASS (psym) == LOC_STATIC)
+      if (psym->aclass == LOC_STATIC)
 	{
-	  CORE_ADDR addr = SYMBOL_VALUE_ADDRESS (psym);
+	  CORE_ADDR addr = psym->value.address;
 	  if (seen_addrs->find (addr) == seen_addrs->end ())
 	    {
 	      seen_addrs->insert (addr);
@@ -1573,8 +1571,8 @@ sort_pst_symbols (struct objfile *objfile, struct partial_symtab *pst)
 
   std::sort (begin, end, [] (partial_symbol *s1, partial_symbol *s2)
     {
-      return strcmp_iw_ordered (SYMBOL_SEARCH_NAME (s1),
-				SYMBOL_SEARCH_NAME (s2)) < 0;
+      return strcmp_iw_ordered (symbol_search_name (s1),
+				symbol_search_name (s2)) < 0;
     });
 }
 
@@ -1621,17 +1619,18 @@ psymbol_hash (const void *addr, int length)
 {
   unsigned long h = 0;
   struct partial_symbol *psymbol = (struct partial_symbol *) addr;
-  unsigned int lang = psymbol->ginfo.language;
-  unsigned int domain = PSYMBOL_DOMAIN (psymbol);
-  unsigned int theclass = PSYMBOL_CLASS (psymbol);
+  unsigned int lang = psymbol->language;
+  unsigned int domain = psymbol->domain;
+  unsigned int theclass = psymbol->aclass;
 
-  h = hash_continue (&psymbol->ginfo.value, sizeof (psymbol->ginfo.value), h);
+  h = hash_continue (&psymbol->value, sizeof (psymbol->value), h);
   h = hash_continue (&lang, sizeof (unsigned int), h);
   h = hash_continue (&domain, sizeof (unsigned int), h);
   h = hash_continue (&theclass, sizeof (unsigned int), h);
   /* Note that psymbol names are interned via symbol_set_names, so
      there's no need to hash the contents of the name here.  */
-  h = hash_continue (&psymbol->ginfo.name, sizeof (psymbol->ginfo.name), h);
+  h = hash_continue (&psymbol->name,
+		     sizeof (psymbol->name), h);
 
   return h;
 }
@@ -1646,15 +1645,15 @@ psymbol_compare (const void *addr1, const void *addr2, int length)
   struct partial_symbol *sym1 = (struct partial_symbol *) addr1;
   struct partial_symbol *sym2 = (struct partial_symbol *) addr2;
 
-  return (memcmp (&sym1->ginfo.value, &sym2->ginfo.value,
-                  sizeof (sym1->ginfo.value)) == 0
-	  && sym1->ginfo.language == sym2->ginfo.language
-          && PSYMBOL_DOMAIN (sym1) == PSYMBOL_DOMAIN (sym2)
-          && PSYMBOL_CLASS (sym1) == PSYMBOL_CLASS (sym2)
+  return (memcmp (&sym1->value, &sym2->value,
+                  sizeof (sym1->value)) == 0
+	  && sym1->language == sym2->language
+          && sym1->domain == sym2->domain
+          && sym1->aclass == sym2->aclass
 	  /* Note that psymbol names are interned via
 	     symbol_set_names, so there's no need to compare the
 	     contents of the name here.  */
-          && sym1->ginfo.name == sym2->ginfo.name);
+          && sym1->name == sym2->name);
 }
 
 /* Initialize a partial symbol bcache.  */
@@ -1719,18 +1718,15 @@ add_psymbol_to_bcache (const char *name, int namelength, int copy_name,
 {
   struct partial_symbol psymbol;
 
-  /* We must ensure that the entire struct has been zeroed before
-     assigning to it, because an assignment may not touch some of the
-     holes.  */
-  memset (&psymbol, 0, sizeof (psymbol));
+  psymbol.value.address = coreaddr;
+  psymbol.section = -1;
+  psymbol.domain = domain;
+  psymbol.aclass = theclass;
 
-  SYMBOL_VALUE_ADDRESS (&psymbol) = coreaddr;
-  SYMBOL_SECTION (&psymbol) = -1;
-  SYMBOL_SET_LANGUAGE (&psymbol, language, &objfile->objfile_obstack);
-  PSYMBOL_DOMAIN (&psymbol) = domain;
-  PSYMBOL_CLASS (&psymbol) = theclass;
-
-  SYMBOL_SET_NAMES (&psymbol, name, namelength, copy_name, objfile);
+  memset (&psymbol.language_specific, 0, sizeof (psymbol.language_specific));
+  psymbol.ada_mangled = 0;
+  symbol_set_language (&psymbol, language, &objfile->objfile_obstack);
+  symbol_set_names (&psymbol, name, namelength, copy_name, objfile);
 
   /* Stash the partial symbol away in the cache.  */
   return psymbol_bcache_full (&psymbol, objfile->psymbol_cache, added);
@@ -2252,13 +2248,13 @@ maintenance_check_psymtabs (const char *ignore, int from_tty)
     length = ps->n_static_syms;
     while (length--)
       {
-	sym = block_lookup_symbol (b, SYMBOL_SEARCH_NAME (*psym),
+	sym = block_lookup_symbol (b, symbol_search_name (*psym),
 				   symbol_name_match_type::SEARCH_NAME,
-				   SYMBOL_DOMAIN (*psym));
+				   (*psym)->domain);
 	if (!sym)
 	  {
 	    printf_filtered ("Static symbol `");
-	    puts_filtered (SYMBOL_LINKAGE_NAME (*psym));
+	    puts_filtered ((*psym)->name);
 	    printf_filtered ("' only found in ");
 	    puts_filtered (ps->filename);
 	    printf_filtered (" psymtab\n");
@@ -2270,13 +2266,13 @@ maintenance_check_psymtabs (const char *ignore, int from_tty)
     length = ps->n_global_syms;
     while (length--)
       {
-	sym = block_lookup_symbol (b, SYMBOL_SEARCH_NAME (*psym),
+	sym = block_lookup_symbol (b, symbol_search_name (*psym),
 				   symbol_name_match_type::SEARCH_NAME,
-				   SYMBOL_DOMAIN (*psym));
+				   (*psym)->domain);
 	if (!sym)
 	  {
 	    printf_filtered ("Global symbol `");
-	    puts_filtered (SYMBOL_LINKAGE_NAME (*psym));
+	    puts_filtered ((*psym)->name);
 	    printf_filtered ("' only found in ");
 	    puts_filtered (ps->filename);
 	    printf_filtered (" psymtab\n");