Enable the new DWARF indexer

This patch finally enables the new indexer.  It is left until this
point in the series to avoid any regressions; in particular, it has to
come after the changes to the DWARF index writer to avoid this
problem.

However, if you experiment with the series, this patch can be moved
anywhere from the patch to wire in the new reader to this point.
Moving this patch around is how I got separate numbers for the
parallelization and background finalization patches.

In the ongoing performance example, this reduces the time from the
baseline of 1.598869 to 0.903534.

gdb/dwarf2/read.c

@@ -5706,7 +5706,8 @@ dwarf2_initialize_objfile (struct objfile *objfile)
     }
 
   global_index_cache.miss ();
-  objfile->qf.push_front (make_lazy_dwarf_reader ());
+  per_bfd->using_index = true;
+  objfile->qf.push_front (make_cooked_index_funcs ());
 }
 
 

gdb/testsuite/gdb.base/maint.exp

@@ -200,11 +200,11 @@ set re \
 	 "  Number of symbol tables: $decimal" \
 	 "  Number of symbol tables with line tables: $decimal" \
 	 "  Number of symbol tables with blockvectors: $decimal" \
-	 "(  Number of read CUs: $decimal" \
-	 "  Number of unread CUs: $decimal" \
-	 ")?(  Number of \"partial\" symbols read: $decimal" \
+	 "(  Number of \"partial\" symbols read: $decimal" \
 	 ")?(  Number of psym tables \\(not yet expanded\\): $decimal" \
 	 ")?(  Total memory used for psymbol cache: $decimal" \
+	 ")?(  Number of read CUs: $decimal" \
+	 "  Number of unread CUs: $decimal" \
 	 ")?  Total memory used for objfile obstack: $decimal" \
 	 "  Total memory used for BFD obstack: $decimal" \
 	 "  Total memory used for string cache: $decimal" \
@@ -224,12 +224,17 @@ gdb_test_no_output "maint print dummy-frames"
 
 set header 0
 set psymtabs 0
+set cooked_index 0
 set symtabs 0
 gdb_test_multiple "maint print objfiles" "" -lbl {
     -re "\r\nObject file.*maint($EXEEXT)?:  Objfile at ${hex}" {
 	set header 1
 	exp_continue
     }
+    -re "\r\nCooked index" {
+	set cooked_index 1
+	exp_continue
+    }
     -re "\r\nPsymtabs:\[\r\t \]+" {
 	set psymtabs 1
 	exp_continue
@@ -248,6 +253,9 @@ proc maint_pass_if {val name} {
 }
 
 maint_pass_if $header   "maint print objfiles: header"
+if {$cooked_index} {
+    set have_psyms 0
+}
 if { $have_psyms } {
     maint_pass_if $psymtabs "maint print objfiles: psymtabs"
 }

gdb/testsuite/gdb.dwarf2/dw2-missing-cu-tag.exp

@@ -54,8 +54,7 @@ clean_restart
 set pattern1 \
     [multi_line \
 	 "Reading symbols from \[^\r\n\]+" \
-	 "Dwarf Error: unexpected tag 'DW_TAG_subprogram' at offset $hex \\\[\[^\r\n\]+\\\]" \
-	 "\\(No debugging symbols \[^\r\n\]+\\)"]
+	 "Dwarf Error: unexpected tag 'DW_TAG_subprogram' at offset $hex \\\[\[^\r\n\]+\\\]"]
 
 # This pattern is hit when GDB does use -readnow (e.g. running with
 # --target_board=readnow).

gdb/testsuite/lib/gdb.exp

@@ -8085,7 +8085,7 @@ proc ensure_gdb_index { binfile {style ""} } {
 	    set has_index 1
 	    gdb_test_lines "" $gdb_test_name ".*"
 	}
-	-re "\r\nPsymtabs:(?=\r\n)" {
+	-re "\r\n(Cooked index in use|Psymtabs)(?=\r\n)" {
 	    gdb_test_lines "" $gdb_test_name ".*"
 	}
 	-re ".gdb_index: faked for \"readnow\"" {