[obv] minor comment cleanups in dwarf2read.c

[obv] minor comment cleanups in dwarf2read.c

[Doug Evans]

Hi.

Checked in as obvious.

2009-05-26  Doug Evans  <dje@google.com>

	* dwarf2read.c (follow_die_ref): Add comment.
	(dwarf2_mark_helper): Tweak comment.
	(dwarf2_mark): Move description to its proper place.

Index: dwarf2read.c
===================================================================
RCS file: /cvs/src/src/gdb/dwarf2read.c,v
retrieving revision 1.304
diff -u -p -r1.304 dwarf2read.c
--- dwarf2read.c	21 May 2009 07:57:45 -0000	1.304
+++ dwarf2read.c	26 May 2009 21:21:05 -0000
@@ -9577,6 +9577,10 @@ maybe_queue_comp_unit (struct dwarf2_cu 
   queue_comp_unit (per_cu, this_cu->objfile);
 }
 
+/* Follow reference attribute ATTR of SRC_DIE.
+   On entry *REF_CU is the CU of SRC_DIE.
+   On exit *REF_CU is the CU of the result.  */
+
 static struct die_info *
 follow_die_ref (struct die_info *src_die, struct attribute *attr,
 		struct dwarf2_cu **ref_cu)
@@ -10830,9 +10834,6 @@ get_die_type (struct die_info *die, stru
     return NULL;
 }
 
-/* Set the mark field in CU and in every other compilation unit in the
-   cache that we must keep because we are keeping CU.  */
-
 /* Add a dependence relationship from CU to REF_PER_CU.  */
 
 static void
@@ -10853,7 +10854,8 @@ dwarf2_add_dependence (struct dwarf2_cu 
     *slot = ref_per_cu;
 }
 
-/* Set the mark field in CU and in every other compilation unit in the
+/* Subroutine of dwarf2_mark to pass to htab_traverse.
+   Set the mark field in every compilation unit in the
    cache that we must keep because we are keeping CU.  */
 
 static int
@@ -10872,6 +10874,9 @@ dwarf2_mark_helper (void **slot, void *d
   return 1;
 }
 
+/* Set the mark field in CU and in every other compilation unit in the
+   cache that we must keep because we are keeping CU.  */
+
 static void
 dwarf2_mark (struct dwarf2_cu *cu)
 {