1 files changed, 88 insertions, 37 deletions

diff --git a/gcc/gengtype.c b/gcc/gengtype.c
index b16a33ac04d..9a7de9fb9a9 100644
--- a/gcc/gengtype.c
+++ b/gcc/gengtype.c
@@ -1571,7 +1571,7 @@ open_base_files (void)
       "optabs.h", "libfuncs.h", "debug.h", "ggc.h", "cgraph.h",
       "tree-flow.h", "reload.h", "cpp-id-data.h", "tree-chrec.h",
       "cfglayout.h", "except.h", "output.h", "gimple.h", "cfgloop.h",
-      "target.h", "ipa-prop.h", "lto-streamer.h", NULL
+      "target.h", "ipa-prop.h", "lto-streamer.h", "target-globals.h", NULL
     };
     const char *const *ifp;
     outf_p gtype_desc_c;
@@ -3174,8 +3174,81 @@ finish_root_table (struct flist *flp, const char *pfx, const char *lastname,
   }
 }
 
+/* Write the first three fields (pointer, count and stride) for
+   root NAME to F.  V and LINE are as for write_root.
+
+   Return true if the entry could be written; return false on error.  */
+
+static bool
+start_root_entry (outf_p f, pair_p v, const char *name, struct fileloc *line)
+{
+  type_p ap;
+
+  if (!v)
+    {
+      error_at_line (line, "`%s' is too complex to be a root", name);
+      return false;
+    }
+
+  oprintf (f, "  {\n");
+  oprintf (f, "    &%s,\n", name);
+  oprintf (f, "    1");
+
+  for (ap = v->type; ap->kind == TYPE_ARRAY; ap = ap->u.a.p)
+    if (ap->u.a.len[0])
+      oprintf (f, " * (%s)", ap->u.a.len);
+    else if (ap == v->type)
+      oprintf (f, " * ARRAY_SIZE (%s)", v->name);
+  oprintf (f, ",\n");
+  oprintf (f, "    sizeof (%s", v->name);
+  for (ap = v->type; ap->kind == TYPE_ARRAY; ap = ap->u.a.p)
+    oprintf (f, "[0]");
+  oprintf (f, "),\n");
+  return true;
+}
+
+/* A subroutine of write_root for writing the roots for field FIELD_NAME,
+   which has type FIELD_TYPE.  Parameters F to EMIT_PCH are the parameters
+   of the caller.  */
+
+static void
+write_field_root (outf_p f, pair_p v, type_p type, const char *name,
+		  int has_length, struct fileloc *line, const char *if_marked,
+		  bool emit_pch, type_p field_type, const char *field_name)
+{
+  /* If the field reference is relative to V, rather than to some
+     subcomponent of V, we can mark any subarrays with a single stride.
+     We're effectively treating the field as a global variable in its
+     own right.  */
+  if (v && type == v->type)
+    {
+      struct pair newv;
+
+      newv = *v;
+      newv.type = field_type;
+      newv.name = ACONCAT ((v->name, ".", field_name, NULL));
+      v = &newv;
+    }
+  /* Otherwise, any arrays nested in the structure are too complex to
+     handle.  */
+  else if (field_type->kind == TYPE_ARRAY)
+    v = NULL;
+  write_root (f, v, field_type, ACONCAT ((name, ".", field_name, NULL)),
+	      has_length, line, if_marked, emit_pch);
+}
+
 /* Write out to F the table entry and any marker routines needed to
-   mark NAME as TYPE.  The original variable is V, at LINE.
+   mark NAME as TYPE.  V can be one of three values:
+
+     - null, if NAME is too complex to represent using a single
+       count and stride.  In this case, it is an error for NAME to
+       contain any gc-ed data.
+
+     - the outermost array that contains NAME, if NAME is part of an array.
+
+     - the C variable that contains NAME, if NAME is not part of an array.
+
+   LINE is the line of the C source that declares the root variable.
    HAS_LENGTH is nonzero iff V was a variable-length array.  IF_MARKED
    is nonzero iff we are building the root table for hash table caches.  */
 
@@ -3232,27 +3305,18 @@ write_root (outf_p f, pair_p v, type_p type, const char *name, int has_length,
 		    validf = ufld;
 		  }
 		if (validf != NULL)
-		  {
-		    char *newname;
-		    newname = xasprintf ("%s.%s.%s",
-					 name, fld->name, validf->name);
-		    write_root (f, v, validf->type, newname, 0, line,
-				if_marked, emit_pch);
-		    free (newname);
-		  }
+		  write_field_root (f, v, type, name, 0, line, if_marked,
+				    emit_pch, validf->type,
+				    ACONCAT ((fld->name, ".",
+					      validf->name, NULL)));
 	      }
 	    else if (desc)
 	      error_at_line (line,
 		     "global `%s.%s' has `desc' option but is not union",
 			     name, fld->name);
 	    else
-	      {
-		char *newname;
-		newname = xasprintf ("%s.%s", name, fld->name);
-		write_root (f, v, fld->type, newname, 0, line, if_marked,
-			    emit_pch);
-		free (newname);
-	      }
+	      write_field_root (f, v, type, name, 0, line, if_marked,
+				emit_pch, fld->type, fld->name);
 	  }
       }
       break;
@@ -3269,22 +3333,10 @@ write_root (outf_p f, pair_p v, type_p type, const char *name, int has_length,
 
     case TYPE_POINTER:
       {
-	type_p ap, tp;
-
-	oprintf (f, "  {\n");
-	oprintf (f, "    &%s,\n", name);
-	oprintf (f, "    1");
-
-	for (ap = v->type; ap->kind == TYPE_ARRAY; ap = ap->u.a.p)
-	  if (ap->u.a.len[0])
-	    oprintf (f, " * (%s)", ap->u.a.len);
-	  else if (ap == v->type)
-	    oprintf (f, " * ARRAY_SIZE (%s)", v->name);
-	oprintf (f, ",\n");
-	oprintf (f, "    sizeof (%s", v->name);
-	for (ap = v->type; ap->kind == TYPE_ARRAY; ap = ap->u.a.p)
-	  oprintf (f, "[0]");
-	oprintf (f, "),\n");
+	type_p tp;
+
+	if (!start_root_entry (f, v, name, line))
+	  return;
 
 	tp = type->u.p;
 
@@ -3331,10 +3383,9 @@ write_root (outf_p f, pair_p v, type_p type, const char *name, int has_length,
 
     case TYPE_STRING:
       {
-	oprintf (f, "  {\n");
-	oprintf (f, "    &%s,\n", name);
-	oprintf (f, "    1, \n");
-	oprintf (f, "    sizeof (%s),\n", v->name);
+	if (!start_root_entry (f, v, name, line))
+	  return;
+
 	oprintf (f, "    (gt_pointer_walker) &gt_ggc_m_S,\n");
 	oprintf (f, "    (gt_pointer_walker) &gt_pch_n_S\n");
 	oprintf (f, "  },\n");