[RFA 11/15] Allocate the address map on the psymtab obstack

[Tom Tromey <tom@tromey.com>]

After this patch, the psymtab address map will now be allocated on the
psymtab obstack rather than the objfile obstack.  This also changes
the psymtab storage object to make the obstack private; this will be
used later.

2018-05-10  Tom Tromey  <tom@tromey.com>

	* psymtab.h (psymtab_storage::obstack): New method.
	<m_obstack>: Rename from obstack; now private.
	* psymtab.c (psymtab_storage): Update.
	* dwarf2read.c (create_addrmap_from_index)
	(create_addrmap_from_aranges, dwarf2_build_psymtabs_hard):
	Update.
---
 gdb/ChangeLog    |  9 +++++++++
 gdb/dwarf2read.c |  6 +++---
 gdb/psymtab.c    |  4 ++--
 gdb/psymtab.h    | 15 +++++++++++----
 4 files changed, 25 insertions(+), 9 deletions(-)

diff --git a/gdb/dwarf2read.c b/gdb/dwarf2read.c
index 03cb4e9d1e..034d5f477f 100644
--- a/gdb/dwarf2read.c
+++ b/gdb/dwarf2read.c
@@ -3187,7 +3187,7 @@ create_addrmap_from_index (struct dwarf2_per_objfile *dwarf2_per_objfile,
     }
 
   objfile->partial_symtabs->psymtabs_addrmap
-    = addrmap_create_fixed (mutable_map, &objfile->objfile_obstack);
+    = addrmap_create_fixed (mutable_map, objfile->partial_symtabs->obstack ());
 }
 
 /* Read the address map data from DWARF-5 .debug_aranges, and use it to
@@ -3348,7 +3348,7 @@ create_addrmap_from_aranges (struct dwarf2_per_objfile *dwarf2_per_objfile,
     }
 
   objfile->partial_symtabs->psymtabs_addrmap
-    = addrmap_create_fixed (mutable_map, &objfile->objfile_obstack);
+    = addrmap_create_fixed (mutable_map, objfile->partial_symtabs->obstack ());
 }
 
 /* Find a slot in the mapped index INDEX for the object named NAME.
@@ -8424,7 +8424,7 @@ dwarf2_build_psymtabs_hard (struct dwarf2_per_objfile *dwarf2_per_objfile)
 
   objfile->partial_symtabs->psymtabs_addrmap
     = addrmap_create_fixed (objfile->partial_symtabs->psymtabs_addrmap,
-			    &objfile->objfile_obstack);
+			    objfile->partial_symtabs->obstack ());
   /* At this point we want to keep the address map.  */
   save_psymtabs_addrmap.release ();
 
diff --git a/gdb/psymtab.c b/gdb/psymtab.c
index f50d0576f8..a7bec436e0 100644
--- a/gdb/psymtab.c
+++ b/gdb/psymtab.c
@@ -68,8 +68,8 @@ static struct compunit_symtab *psymtab_to_symtab (struct objfile *objfile,
 \f
 
 psymtab_storage::psymtab_storage (struct objfile *objfile)
-  : obstack (&objfile->objfile_obstack),
-    psymbol_cache (psymbol_bcache_init ())
+  : psymbol_cache (psymbol_bcache_init ()),
+    m_obstack (&objfile->objfile_obstack)
 {
 }
 
diff --git a/gdb/psymtab.h b/gdb/psymtab.h
index 58c4bee98a..36dba3245c 100644
--- a/gdb/psymtab.h
+++ b/gdb/psymtab.h
@@ -55,6 +55,11 @@ public:
 
   void discard_psymtab (struct partial_symtab *pst);
 
+  struct obstack *obstack ()
+  {
+    return m_obstack;
+  }
+
 
   /* Each objfile points to a linked list of partial symtabs derived from
      this file, one partial symtab structure for each compilation unit
@@ -73,10 +78,6 @@ public:
 
   struct partial_symtab *free_psymtabs = nullptr;
 
-  /* The obstack where allocations are made.  */
-
-  struct obstack *obstack;
-
   /* A byte cache where we can stash arbitrary "chunks" of bytes that
      will not change.  */
 
@@ -87,6 +88,12 @@ public:
 
   std::vector<partial_symbol *> global_psymbols;
   std::vector<partial_symbol *> static_psymbols;
+
+private:
+
+  /* The obstack where allocations are made.  */
+
+  struct obstack *m_obstack;
 };
 
 
-- 
2.13.6