dwarflint: In all_dies_iterator, replace parent () with stack ()

- use it in locstats to find the nearest parental DIE with non-empty ranges

diff --git a/dwarflint/all-dies-it.hh b/dwarflint/all-dies-it.hh
index 615825762813239d56ccb6f7c0e4976341a8cd06..10619e6ad598aee387bc68b3a2432e1d381735f3 100644 (file)
--- a/dwarflint/all-dies-it.hh
+++ b/dwarflint/all-dies-it.hh
@@ -122,11 +122,19 @@ public:
     return *_m_die_it;
   }
 
-  typename T::debug_info_entry const &parent ()
+  std::vector<typename T::debug_info_entry> stack () const
   {
-    if (_m_die_it_stack.empty ())
-      throw std::runtime_error ("no parent");
-    return *_m_die_it_stack.back ().first;
+    std::vector<typename T::debug_info_entry> ret;
+    for (auto it = _m_die_it_stack.begin ();
+        it != _m_die_it_stack.end (); ++it)
+      ret.push_back (*it->first);
+    ret.push_back (*_m_die_it);
+    return ret;
+  }
+
+  typename T::compile_unit cu () const
+  {
+    return *_m_cu_it;
   }
 
   typename T::debug_info_entry const *operator-> () const

diff --git a/dwarflint/locstats.cc b/dwarflint/locstats.cc
index fe7f57f69d74f1237df182c0ea5ba3467901b191..32f3010fea9e167f35bdef2a7ca40512408f54ba 100644 (file)
--- a/dwarflint/locstats.cc
+++ b/dwarflint/locstats.cc
@@ -26,6 +26,8 @@
 #include "highlevel_check.hh"
 #include "all-dies-it.hh"
 #include "option.hh"
+#include "messages.h"
+#include "pri.hh"
 
 #include <sstream>
 
@@ -120,6 +122,19 @@ namespace
       return at (0).start == value;
     }
   };
+
+  class no_ranges {};
+
+  // Look through the stack of parental dies and return the non-empty
+  // ranges instance closest to the stack top (i.e. die_stack.end ()).
+  dwarf::ranges
+  find_ranges (std::vector<dwarf::debug_info_entry> const &die_stack)
+  {
+    for (auto it = die_stack.rbegin (); it != die_stack.rend (); ++it)
+      if (!it->ranges ().empty ())
+       return it->ranges ();
+    throw no_ranges ();
+  }
 }
 
 locstats::locstats (checkstack &stack, dwarflint &lint)
@@ -143,8 +158,6 @@ locstats::locstats (checkstack &stack, dwarflint &lint)
       if (!is_formal_parameter && die.tag () != DW_TAG_variable)
        continue;
 
-      dwarf::debug_info_entry const &parent = it.parent ();
-
       dwarf::debug_info_entry::attributes_type const &attrs
        = die.attributes ();
 
@@ -154,9 +167,10 @@ locstats::locstats (checkstack &stack, dwarflint &lint)
 
       // Of formal parameters we ignore those that are children of
       // subprograms that are themselves declarations.
+      std::vector<dwarf::debug_info_entry> const &die_stack = it.stack ();
       if (is_formal_parameter)
        {
-         if (parent.attributes ().find (DW_AT_declaration)
+         if (die_stack.back ().attributes ().find (DW_AT_declaration)
              != die.attributes ().end ())
            continue;
        }
@@ -207,34 +221,41 @@ locstats::locstats (checkstack &stack, dwarflint &lint)
            // Globals and statics have non-list location that is a
            // singleton DW_OP_addr expression.
            continue;
-         coverage = 100;
+         coverage = (len == 0) ? 0 : 100;
        }
 
       // location list
       else
        {
-         dwarf::ranges const &ranges
-           = die.ranges ().empty () ? parent.ranges () : die.ranges ();
-         if (ranges.empty ())
-           // what?
-           continue;
-
-         size_t length = 0;
-         size_t covered = 0;
-         for (dwarf::ranges::const_iterator rit = ranges.begin ();
-              rit != ranges.end (); ++rit)
+         try
+           {
+             dwarf::ranges ranges (find_ranges (die_stack));
+             size_t length = 0;
+             size_t covered = 0;
+             for (dwarf::ranges::const_iterator rit = ranges.begin ();
+                  rit != ranges.end (); ++rit)
+               {
+                 Dwarf_Addr low = (*rit).first;
+                 Dwarf_Addr high = (*rit).second;
+                 length += high - low;
+                 /*std::cerr << std::endl << " " << low << ".." << high
+                   << std::endl;*/
+                 for (Dwarf_Addr addr = low; addr < high; ++addr)
+                   if (dwarf_getlocation_addr (locattr, addr,
+                                               NULL, NULL, 0) > 0)
+                     covered++;
+               }
+             coverage = 100 * covered / length;
+           }
+         catch (no_ranges const &e)
            {
-             Dwarf_Addr low = (*rit).first;
-             Dwarf_Addr high = (*rit).second;
-             length += high - low;
-             /*std::cerr << std::endl << " " << low << ".." << high
-               << std::endl;*/
-             for (Dwarf_Addr addr = low; addr < high; ++addr)
-               if (dwarf_getlocation_addr (locattr, addr,
-                                           NULL, NULL, 0) > 0)
-                 covered++;
+             struct where where = WHERE (sec_info, NULL);
+             where_reset_1 (&where, it.cu ().offset ());
+             where_reset_2 (&where, die.offset ());
+             wr_error (where)
+               << "no ranges for this DIE." << std::endl;
+             continue;
            }
-         coverage = 100 * covered / length;
        }
 
       tally[coverage]++;