gdb: Add support for tracking the DWARF line table is-stmt field

[deliverable/binutils-gdb.git] / gdb / buildsym.c

diff --git a/gdb/buildsym.c b/gdb/buildsym.c
index 8e05706c4be7ead2ce8dbae8d76f7c7c2a60e6a7..24aeba8e25220b80210e0d08b0a8badf6cd848af 100644 (file)
--- a/gdb/buildsym.c
+++ b/gdb/buildsym.c
@@ -1,5 +1,5 @@
 /* Support routines for building symbol tables in GDB's internal format.
-   Copyright (C) 1986-2019 Free Software Foundation, Inc.
+   Copyright (C) 1986-2020 Free Software Foundation, Inc.
 
    This file is part of GDB.
 
@@ -49,8 +49,6 @@ struct pending_block
     struct block *block;
   };
 
-static int compare_line_numbers (const void *ln1p, const void *ln2p);
-
 /* Initial sizes of data structures.  These are realloc'd larger if
    needed, and realloc'd down to the size actually used, when
    completed.  */
@@ -122,7 +120,7 @@ buildsym_compunit::get_macro_table ()
 {
   if (m_pending_macros == nullptr)
     m_pending_macros = new_macro_table (&m_objfile->per_bfd->storage_obstack,
-                                       &m_objfile->per_bfd->macro_cache,
+                                       &m_objfile->per_bfd->string_cache,
                                        m_compunit_symtab);
   return m_pending_macros;
 }
@@ -137,7 +135,7 @@ add_symbol_to_list (struct symbol *symbol, struct pending **listhead)
   struct pending *link;
 
   /* If this is an alias for another symbol, don't add it.  */
-  if (symbol->ginfo.name && symbol->ginfo.name[0] == '#')
+  if (symbol->linkage_name () && symbol->linkage_name ()[0] == '#')
     return;
 
   /* We keep PENDINGSIZE symbols in each link of the list.  If we
@@ -166,7 +164,7 @@ find_symbol_in_list (struct pending *list, char *name, int length)
     {
       for (j = list->nsyms; --j >= 0;)
        {
-         pp = SYMBOL_LINKAGE_NAME (list->symbol[j]);
+         pp = list->symbol[j]->linkage_name ();
          if (*pp == *name && strncmp (pp, name, length) == 0
              && pp[length] == '\0')
            {
@@ -321,7 +319,7 @@ buildsym_compunit::finish_block_internal
        {
          complaint (_("block end address less than block "
                       "start address in %s (patched it)"),
-                    SYMBOL_PRINT_NAME (symbol));
+                    symbol->print_name ());
        }
       else
        {
@@ -358,7 +356,7 @@ buildsym_compunit::finish_block_internal
              if (symbol)
                {
                  complaint (_("inner block not inside outer block in %s"),
-                            SYMBOL_PRINT_NAME (symbol));
+                            symbol->print_name ());
                }
              else
                {
@@ -668,16 +666,10 @@ buildsym_compunit::pop_subfile ()
 
 void
 buildsym_compunit::record_line (struct subfile *subfile, int line,
-                               CORE_ADDR pc)
+                               CORE_ADDR pc, bool is_stmt)
 {
   struct linetable_entry *e;
 
-  /* Ignore the dummy line number in libg.o */
-  if (line == 0xffff)
-    {
-      return;
-    }
-
   /* Make sure line vector exists and is big enough.  */
   if (!subfile->line_vector)
     {
@@ -689,6 +681,17 @@ buildsym_compunit::record_line (struct subfile *subfile, int line,
       m_have_line_numbers = true;
     }
 
+  /* If we have a duplicate for the previous entry then ignore the new
+     entry, except, if the new entry is setting the is_stmt flag, then
+     ensure the previous entry respects the new setting.  */
+  e = subfile->line_vector->item + subfile->line_vector->nitems - 1;
+  if (e->line == line && e->pc == pc)
+    {
+      if (is_stmt && !e->is_stmt)
+       e->is_stmt = 1;
+      return;
+    }
+
   if (subfile->line_vector->nitems + 1 >= subfile->line_vector_length)
     {
       subfile->line_vector_length *= 2;
@@ -724,29 +727,10 @@ buildsym_compunit::record_line (struct subfile *subfile, int line,
 
   e = subfile->line_vector->item + subfile->line_vector->nitems++;
   e->line = line;
+  e->is_stmt = is_stmt ? 1 : 0;
   e->pc = pc;
 }
 
-/* Needed in order to sort line tables from IBM xcoff files.  Sigh!  */
-
-static int
-compare_line_numbers (const void *ln1p, const void *ln2p)
-{
-  struct linetable_entry *ln1 = (struct linetable_entry *) ln1p;
-  struct linetable_entry *ln2 = (struct linetable_entry *) ln2p;
-
-  /* Note: this code does not assume that CORE_ADDRs can fit in ints.
-     Please keep it that way.  */
-  if (ln1->pc < ln2->pc)
-    return -1;
-
-  if (ln1->pc > ln2->pc)
-    return 1;
-
-  /* If pc equal, sort by line.  I'm not sure whether this is optimum
-     behavior (see comment at struct linetable in symtab.h).  */
-  return ln1->line - ln2->line;
-}
 \f
 /* Subroutine of end_symtab to simplify it.  Look for a subfile that
    matches the main source file's basename.  If there is only one, and
@@ -964,13 +948,23 @@ buildsym_compunit::end_symtab_with_blockvector (struct block *static_block,
          linetablesize = sizeof (struct linetable) +
            subfile->line_vector->nitems * sizeof (struct linetable_entry);
 
-         /* Like the pending blocks, the line table may be
-            scrambled in reordered executables.  Sort it if
-            OBJF_REORDERED is true.  */
+         const auto lte_is_less_than
+           = [] (const linetable_entry &ln1,
+                 const linetable_entry &ln2) -> bool
+             {
+               return (ln1.pc < ln2.pc);
+             };
+
+         /* Like the pending blocks, the line table may be scrambled in
+            reordered executables.  Sort it if OBJF_REORDERED is true.  It
+            is important to preserve the order of lines at the same
+            address, as this maintains the inline function caller/callee
+            relationships, this is why std::stable_sort is used.  */
          if (m_objfile->flags & OBJF_REORDERED)
-           qsort (subfile->line_vector->item,
-                  subfile->line_vector->nitems,
-                  sizeof (struct linetable_entry), compare_line_numbers);
+           std::stable_sort (subfile->line_vector->item,
+                             subfile->line_vector->item
+                             + subfile->line_vector->nitems,
+                             lte_is_less_than);
        }
 
       /* Allocate a symbol table if necessary.  */