[google,gcc-4_9] Remove unused key field in gcov_fn_info

Index: gcc/coverage.c
===================================================================
--- gcc/coverage.c	(revision 228223)
+++ gcc/coverage.c	(working copy)
@@ -189,7 +189,7 @@  static void read_counts_file (const char *, unsign
 static tree build_var (tree, tree, int);
 static void build_fn_info_type (tree, unsigned, tree);
 static void build_info_type (tree, tree);
-static tree build_fn_info (const struct coverage_data *, tree, tree);
+static tree build_fn_info (const struct coverage_data *, tree);
 static tree build_info (tree, tree);
 static bool coverage_obj_init (void);
 static vec<constructor_elt, va_gc> *coverage_obj_fn
@@ -1668,16 +1668,9 @@  build_fn_info_type (tree type, unsigned counters,
 
   finish_builtin_struct (ctr_info, "__gcov_ctr_info", fields, NULL_TREE);
 
-  /* key */
-  field = build_decl (BUILTINS_LOCATION, FIELD_DECL, NULL_TREE,
-		      build_pointer_type (build_qualified_type
-					  (gcov_info_type, TYPE_QUAL_CONST)));
-  fields = field;
-
   /* ident */
   field = build_decl (BUILTINS_LOCATION, FIELD_DECL, NULL_TREE,
 		      get_gcov_unsigned_t ());
-  DECL_CHAIN (field) = fields;
   fields = field;
 
   /* lineno_checksum */
@@ -1705,10 +1698,10 @@  build_fn_info_type (tree type, unsigned counters,
 
 /* Returns a CONSTRUCTOR for a gcov_fn_info.  DATA is
    the coverage data for the function and TYPE is the gcov_fn_info
-   RECORD_TYPE.  KEY is the object file key.  */
+   RECORD_TYPE.  */
 
 static tree
-build_fn_info (const struct coverage_data *data, tree type, tree key)
+build_fn_info (const struct coverage_data *data, tree type)
 {
   tree fields = TYPE_FIELDS (type);
   tree ctr_type;
@@ -1716,11 +1709,6 @@  static tree
   vec<constructor_elt, va_gc> *v1 = NULL;
   vec<constructor_elt, va_gc> *v2 = NULL;
 
-  /* key */
-  CONSTRUCTOR_APPEND_ELT (v1, fields,
-			  build1 (ADDR_EXPR, TREE_TYPE (fields), key));
-  fields = DECL_CHAIN (fields);
-  
   /* ident */
   CONSTRUCTOR_APPEND_ELT (v1, fields,
 			  build_int_cstu (get_gcov_unsigned_t (),
@@ -2556,7 +2544,7 @@  static vec<constructor_elt, va_gc> *
 coverage_obj_fn (vec<constructor_elt, va_gc> *ctor, tree fn,
 		 struct coverage_data const *data)
 {
-  tree init = build_fn_info (data, gcov_fn_info_type, gcov_info_var);
+  tree init = build_fn_info (data, gcov_fn_info_type);
   tree var = build_var (fn, gcov_fn_info_type, -1);
   
   DECL_INITIAL (var) = init;
Index: libgcc/libgcov-driver.c
===================================================================
--- libgcc/libgcov-driver.c	(revision 227984)
+++ libgcc/libgcov-driver.c	(working copy)
@@ -380,7 +380,7 @@  gcov_compute_histogram (struct gcov_summary *sum)
         {
           gfi_ptr = gi_ptr->functions[f_ix];
 
-          if (!gfi_ptr || gfi_ptr->key != gi_ptr)
+          if (!gfi_ptr)
             continue;
 
           ci_ptr = &gfi_ptr->ctrs[ctr_info_ix];
@@ -430,9 +430,6 @@  gcov_exit_compute_summary (struct gcov_summary *th
         {
           gfi_ptr = gi_ptr->functions[f_ix];
 
-          if (gfi_ptr && gfi_ptr->key != gi_ptr)
-            gfi_ptr = 0;
-
           crc32 = crc32_unsigned (crc32, gfi_ptr ? gfi_ptr->cfg_checksum : 0);
           crc32 = crc32_unsigned (crc32,
                                   gfi_ptr ? gfi_ptr->lineno_checksum : 0);
@@ -688,7 +685,7 @@  gcov_exit_merge_gcda (struct gcov_info *gi_ptr,
       if (length != GCOV_TAG_FUNCTION_LENGTH)
         goto read_mismatch;
 
-      if (!gfi_ptr || gfi_ptr->key != gi_ptr)
+      if (!gfi_ptr)
         {
           /* This function appears in the other program.  We
              need to buffer the information in order to write
@@ -832,10 +829,8 @@  gcov_write_func_counters (struct gcov_info *gi_ptr
       else
         {
           gfi_ptr = gi_ptr->functions[f_ix];
-          if (gfi_ptr && gfi_ptr->key == gi_ptr)
+          if (gfi_ptr)
             length = GCOV_TAG_FUNCTION_LENGTH;
-          else
-            length = 0;
         }
 
       gcov_write_tag_length (GCOV_TAG_FUNCTION, length);
@@ -1474,7 +1469,7 @@  gcov_clear (void)
           const struct gcov_fn_info *gfi_ptr = gi_ptr->functions[f_ix];
           const struct gcov_ctr_info *ci_ptr;
 
-          if (!gfi_ptr || gfi_ptr->key != gi_ptr)
+          if (!gfi_ptr)
             continue;
           ci_ptr = gfi_ptr->ctrs;
           for (t_ix = 0; t_ix != GCOV_COUNTERS; t_ix++)
Index: libgcc/libgcov-util.c
===================================================================
--- libgcc/libgcov-util.c	(revision 227984)
+++ libgcc/libgcov-util.c	(working copy)
@@ -180,7 +180,6 @@  tag_function (unsigned tag ATTRIBUTE_UNUSED, unsig
         fprintf (stderr, "Function id=%d fixed up\n", curr_fn_info->ident);
     }
 
-  curr_fn_info->key = curr_gcov_info;
   curr_fn_info->ident = gcov_read_unsigned ();
   curr_fn_info->lineno_checksum = gcov_read_unsigned ();
   curr_fn_info->cfg_checksum = gcov_read_unsigned ();
@@ -833,9 +832,9 @@  gcov_merge (struct gcov_info *info1, struct gcov_i
       const struct gcov_fn_info *gfi_ptr2 = info2->functions[f_ix];
       const struct gcov_ctr_info *ci_ptr1, *ci_ptr2;
 
-      if (!gfi_ptr1 || gfi_ptr1->key != info1)
+      if (!gfi_ptr1)
         continue;
-      if (!gfi_ptr2 || gfi_ptr2->key != info2)
+      if (!gfi_ptr2)
         continue;
 
       if (gfi_ptr1->cfg_checksum != gfi_ptr2->cfg_checksum)
@@ -1136,7 +1135,7 @@  gcov_profile_scale (struct gcov_info *profile, flo
         const struct gcov_fn_info *gfi_ptr = gi_ptr->functions[f_ix];
         const struct gcov_ctr_info *ci_ptr;
 
-        if (!gfi_ptr || gfi_ptr->key != gi_ptr)
+        if (!gfi_ptr)
           continue;
 
         ci_ptr = gfi_ptr->ctrs;
@@ -1178,7 +1177,7 @@  gcov_profile_normalize (struct gcov_info *profile,
         const struct gcov_fn_info *gfi_ptr = gi_ptr->functions[f_ix];
         const struct gcov_ctr_info *ci_ptr;
 
-        if (!gfi_ptr || gfi_ptr->key != gi_ptr)
+        if (!gfi_ptr)
           continue;
 
         ci_ptr = gfi_ptr->ctrs;
@@ -1264,7 +1263,7 @@  compute_one_gcov (const struct gcov_info *gcov_inf
       {
         unsigned t_ix;
         const struct gcov_fn_info *gfi_ptr = gcov_info->functions[f_ix];
-        if (!gfi_ptr || gfi_ptr->key != gcov_info)
+        if (!gfi_ptr)
           continue;
         const struct gcov_ctr_info *ci_ptr = gfi_ptr->ctrs;
         for (t_ix = 0; t_ix < GCOV_COUNTERS_SUMMABLE; t_ix++)
@@ -1296,9 +1295,9 @@  compute_one_gcov (const struct gcov_info *gcov_inf
       const struct gcov_fn_info *gfi_ptr1 = gcov_info1->functions[f_ix];
       const struct gcov_fn_info *gfi_ptr2 = gcov_info2->functions[f_ix];
 
-      if (!gfi_ptr1 || gfi_ptr1->key != gcov_info1)
+      if (!gfi_ptr1)
         continue;
-      if (!gfi_ptr2 || gfi_ptr2->key != gcov_info2)
+      if (!gfi_ptr2)
         continue;
 
       const struct gcov_ctr_info *ci_ptr1 = gfi_ptr1->ctrs;
@@ -1358,7 +1357,7 @@  gcov_info_count_all_cold (const struct gcov_info *
       unsigned t_ix;
       const struct gcov_fn_info *gfi_ptr = gcov_info->functions[f_ix];
 
-      if (!gfi_ptr || gfi_ptr->key != gcov_info)
+      if (!gfi_ptr)
         continue;
       const struct gcov_ctr_info *ci_ptr = gfi_ptr->ctrs;
       for (t_ix = 0; t_ix < GCOV_COUNTERS_SUMMABLE; t_ix++)
Index: libgcc/libgcov.h
===================================================================
--- libgcc/libgcov.h	(revision 227984)
+++ libgcc/libgcov.h	(working copy)
@@ -224,13 +224,10 @@  struct gcov_ctr_info
 
 /* Information about a single function.  This uses the trailing array
    idiom. The number of counters is determined from the merge pointer
-   array in gcov_info.  The key is used to detect which of a set of
-   comdat functions was selected -- it points to the gcov_info object
-   of the object file containing the selected comdat function.  */
+   array in gcov_info.  */
 
 struct gcov_fn_info
 {
-  const struct gcov_info *key;          /* comdat key */
   gcov_unsigned_t ident;                /* unique ident of function */
   gcov_unsigned_t lineno_checksum;      /* function lineo_checksum */
   gcov_unsigned_t cfg_checksum; /* function cfg checksum */