[gdb/symtab] C++-ify call_site

- add constructor
- add member function call_site::pc ()

Tested on x86_64-linux.

Co-Authored-By: Tom de Vries <tdevries@suse.de>

gdb/dwarf2/frame-tailcall.c

@@ -240,14 +240,14 @@ pretend_pc (struct frame_info *this_frame, struct tailcall_cache *cache)
   gdb_assert (next_levels >= 0);
 
   if (next_levels < chain->callees)
-    return chain->call_site[chain->length - next_levels - 1]->pc;
+    return chain->call_site[chain->length - next_levels - 1]->pc ();
   next_levels -= chain->callees;
 
   /* Otherwise CHAIN->CALLEES are already covered by CHAIN->CALLERS.  */
   if (chain->callees != chain->length)
     {
       if (next_levels < chain->callers)
-	return chain->call_site[chain->callers - next_levels - 1]->pc;
+	return chain->call_site[chain->callers - next_levels - 1]->pc ();
       next_levels -= chain->callers;
     }
 

gdb/dwarf2/loc.c

@@ -654,10 +654,10 @@ call_site_to_target_addr (struct gdbarch *call_site_gdbarch,
 	  {
 	    struct bound_minimal_symbol msym;
 	    
-	    msym = lookup_minimal_symbol_by_pc (call_site->pc - 1);
+	    msym = lookup_minimal_symbol_by_pc (call_site->pc () - 1);
 	    throw_error (NO_ENTRY_VALUE_ERROR,
 			 _("DW_AT_call_target is not specified at %s in %s"),
-			 paddress (call_site_gdbarch, call_site->pc),
+			 paddress (call_site_gdbarch, call_site->pc ()),
 			 (msym.minsym == NULL ? "???"
 			  : msym.minsym->print_name ()));
 			
@@ -666,12 +666,12 @@ call_site_to_target_addr (struct gdbarch *call_site_gdbarch,
 	  {
 	    struct bound_minimal_symbol msym;
 	    
-	    msym = lookup_minimal_symbol_by_pc (call_site->pc - 1);
+	    msym = lookup_minimal_symbol_by_pc (call_site->pc () - 1);
 	    throw_error (NO_ENTRY_VALUE_ERROR,
 			 _("DW_AT_call_target DWARF block resolving "
 			   "requires known frame which is currently not "
 			   "available at %s in %s"),
-			 paddress (call_site_gdbarch, call_site->pc),
+			 paddress (call_site_gdbarch, call_site->pc ()),
 			 (msym.minsym == NULL ? "???"
 			  : msym.minsym->print_name ()));
 			
@@ -700,11 +700,11 @@ call_site_to_target_addr (struct gdbarch *call_site_gdbarch,
 	msym = lookup_minimal_symbol (physname, NULL, NULL);
 	if (msym.minsym == NULL)
 	  {
-	    msym = lookup_minimal_symbol_by_pc (call_site->pc - 1);
+	    msym = lookup_minimal_symbol_by_pc (call_site->pc () - 1);
 	    throw_error (NO_ENTRY_VALUE_ERROR,
 			 _("Cannot find function \"%s\" for a call site target "
 			   "at %s in %s"),
-			 physname, paddress (call_site_gdbarch, call_site->pc),
+			 physname, paddress (call_site_gdbarch, call_site->pc ()),
 			 (msym.minsym == NULL ? "???"
 			  : msym.minsym->print_name ()));
 			
@@ -810,7 +810,7 @@ func_verify_no_selftailcall (struct gdbarch *gdbarch, CORE_ADDR verify_addr)
 static void
 tailcall_dump (struct gdbarch *gdbarch, const struct call_site *call_site)
 {
-  CORE_ADDR addr = call_site->pc;
+  CORE_ADDR addr = call_site->pc ();
   struct bound_minimal_symbol msym = lookup_minimal_symbol_by_pc (addr - 1);
 
   fprintf_unfiltered (gdb_stdlog, " %s(%s)", paddress (gdbarch, addr),
@@ -986,7 +986,7 @@ call_site_find_chain_1 (struct gdbarch *gdbarch, CORE_ADDR caller_pc,
 
 	  if (target_call_site)
 	    {
-	      if (addr_hash.insert (target_call_site->pc).second)
+	      if (addr_hash.insert (target_call_site->pc ()).second)
 		{
 		  /* Successfully entered TARGET_CALL_SITE.  */
 
@@ -1005,7 +1005,7 @@ call_site_find_chain_1 (struct gdbarch *gdbarch, CORE_ADDR caller_pc,
 	      call_site = chain.back ();
 	      chain.pop_back ();
 
-	      size_t removed = addr_hash.erase (call_site->pc);
+	      size_t removed = addr_hash.erase (call_site->pc ());
 	      gdb_assert (removed == 1);
 
 	      target_call_site = call_site->tail_call_next;

gdb/dwarf2/read.c

@@ -13341,7 +13341,6 @@ read_call_site_scope (struct die_info *die, struct dwarf2_cu *cu)
   struct gdbarch *gdbarch = objfile->arch ();
   CORE_ADDR pc, baseaddr;
   struct attribute *attr;
-  struct call_site *call_site, call_site_local;
   void **slot;
   int nparams;
   struct die_info *child_die;
@@ -13366,10 +13365,11 @@ read_call_site_scope (struct die_info *die, struct dwarf2_cu *cu)
   pc = gdbarch_adjust_dwarf2_addr (gdbarch, pc);
 
   if (cu->call_site_htab == NULL)
-    cu->call_site_htab = htab_create_alloc_ex (16, call_site_hash, call_site_eq,
-					       NULL, &objfile->objfile_obstack,
+    cu->call_site_htab = htab_create_alloc_ex (16, call_site::hash,
+					       call_site::eq, NULL,
+					       &objfile->objfile_obstack,
 					       hashtab_obstack_allocate, NULL);
-  call_site_local.pc = pc;
+  struct call_site call_site_local (pc, nullptr, nullptr);
   slot = htab_find_slot (cu->call_site_htab, &call_site_local, INSERT);
   if (*slot != NULL)
     {
@@ -13399,14 +13399,16 @@ read_call_site_scope (struct die_info *die, struct dwarf2_cu *cu)
       nparams++;
     }
 
-  call_site
-    = ((struct call_site *)
-       obstack_alloc (&objfile->objfile_obstack,
-		      sizeof (*call_site)
-		      + (sizeof (*call_site->parameter) * (nparams - 1))));
+  struct call_site *call_site
+    = new (XOBNEWVAR (&objfile->objfile_obstack,
+		      struct call_site,
+		      sizeof (*call_site) + sizeof (call_site->parameter[0]) * nparams))
+    struct call_site (pc, cu->per_cu, per_objfile);
   *slot = call_site;
-  memset (call_site, 0, sizeof (*call_site) - sizeof (*call_site->parameter));
-  call_site->pc = pc;
+
+  /* We never call the destructor of call_site, so we must ensure it is
+     trivially destructible.  */
+  gdb_static_assert(std::is_trivially_destructible<struct call_site>::value);
 
   if (dwarf2_flag_true_p (die, DW_AT_call_tail_call, cu)
       || dwarf2_flag_true_p (die, DW_AT_GNU_tail_call, cu))
@@ -13527,9 +13529,6 @@ read_call_site_scope (struct die_info *die, struct dwarf2_cu *cu)
 		 "block nor reference, for DIE %s [in module %s]"),
 	       sect_offset_str (die->sect_off), objfile_name (objfile));
 
-  call_site->per_cu = cu->per_cu;
-  call_site->per_objfile = per_objfile;
-
   for (child_die = die->child;
        child_die && child_die->tag;
        child_die = child_die->sibling)

gdb/gdbtypes.c

@@ -37,6 +37,7 @@
 #include "cp-support.h"
 #include "bcache.h"
 #include "dwarf2/loc.h"
+#include "dwarf2/read.h"
 #include "gdbcore.h"
 #include "floatformat.h"
 #include "f-lang.h"
@@ -6308,6 +6309,14 @@ objfile_type (struct objfile *objfile)
   return objfile_type;
 }
 
+/* See gdbtypes.h.  */
+
+CORE_ADDR
+call_site::pc () const
+{
+  return m_pc;
+}
+
 void _initialize_gdbtypes ();
 void
 _initialize_gdbtypes ()

gdb/gdbtypes.h

@@ -1793,52 +1793,71 @@ struct call_site_parameter
 
 struct call_site
   {
-    /* Address of the first instruction after this call.  */
+    call_site (CORE_ADDR pc, dwarf2_per_cu_data *per_cu,
+	       dwarf2_per_objfile *per_objfile)
+      : per_cu (per_cu), per_objfile (per_objfile), m_pc (pc)
+    {}
 
-    CORE_ADDR pc;
+    static int
+    eq (const call_site *a, const call_site *b)
+    {
+      return core_addr_eq (&a->m_pc, &b->m_pc);
+    }
+
+    static hashval_t
+    hash (const call_site *a)
+    {
+      return core_addr_hash (&a->m_pc);
+    }
+
+    static int
+    eq (const void *a, const void *b)
+    {
+      return eq ((const call_site *)a, (const call_site *)b);
+    }
+
+    static hashval_t
+    hash (const void *a)
+    {
+      return hash ((const call_site *)a);
+    }
+
+    /* Return the address of the first instruction after this call.  */
+
+    CORE_ADDR pc () const;
 
     /* * List successor with head in FUNC_TYPE.TAIL_CALL_LIST.  */
 
-    struct call_site *tail_call_next;
+    struct call_site *tail_call_next = nullptr;
 
     /* * Describe DW_AT_call_target.  Missing attribute uses
        FIELD_LOC_KIND_DWARF_BLOCK with FIELD_DWARF_BLOCK == NULL.  */
 
-    struct call_site_target target;
+    struct call_site_target target {};
 
     /* * Size of the PARAMETER array.  */
 
-    unsigned parameter_count;
+    unsigned parameter_count = 0;
 
     /* * CU of the function where the call is located.  It gets used
        for DWARF blocks execution in the parameter array below.  */
 
-    dwarf2_per_cu_data *per_cu;
+    dwarf2_per_cu_data *const per_cu = nullptr;
 
     /* objfile of the function where the call is located.  */
 
-    dwarf2_per_objfile *per_objfile;
+    dwarf2_per_objfile *const per_objfile = nullptr;
 
+  private:
+    /* Address of the first instruction after this call.  */
+    const CORE_ADDR m_pc;
+
+  public:
     /* * Describe DW_TAG_call_site's DW_TAG_formal_parameter.  */
 
-    struct call_site_parameter parameter[1];
+    struct call_site_parameter parameter[];
   };
 
-static inline int
-call_site_eq (const void *a_, const void *b_)
-{
-  const struct call_site *a = (const call_site *)a_;
-  const struct call_site *b = (const call_site *)b_;
-  return core_addr_eq (&a->pc, &b->pc);
-}
-
-static inline hashval_t
-call_site_hash (const void *a_)
-{
-  const struct call_site *a = (const call_site *)a_;
-  return core_addr_hash (&a->pc);
-}
-
 /* The type-specific info for TYPE_CODE_FIXED_POINT types.  */
 
 struct fixed_point_type_info

gdb/symtab.c

@@ -334,11 +334,10 @@ search_domain_name (enum search_domain e)
 call_site *
 compunit_symtab::find_call_site (CORE_ADDR pc) const
 {
-  struct call_site call_site_local;
   if (m_call_site_htab == nullptr)
     return nullptr;
 
-  call_site_local.pc = pc;
+  struct call_site call_site_local (pc, nullptr, nullptr);
   void **slot
     = htab_find_slot (m_call_site_htab, &call_site_local, NO_INSERT);
   if (slot == nullptr)