Finish stable split

Long ago, the stable name table and stable pointer tables were one.
Now, they are separate, and have significantly different
implementations. I believe the time has come to finish the split
that began in #7674.

* Divide `rts/Stable` into `rts/StableName` and `rts/StablePtr`.

* Give each table its own mutex.

* Add FFI functions `hs_lock_stable_ptr_table` and
`hs_unlock_stable_ptr_table` and document them.
  These are intended to replace the previously undocumented
`hs_lock_stable_tables` and `hs_lock_stable_tables`,
  which are now documented as deprecated synonyms.

* Make `eqStableName#` use pointer equality instead of unnecessarily
comparing stable name table indices.

Reviewers: simonmar, bgamari, erikd

Reviewed By: bgamari

Subscribers: rwbarton, carter

GHC Trac Issues: #15555

Differential Revision: https://phabricator.haskell.org/D5084

1 files changed, 10 insertions, 3 deletions

diff --git a/rts/RtsStartup.c b/rts/RtsStartup.c
index 0cb1ff9700..5e5aef3505 100644
--- a/rts/RtsStartup.c
+++ b/rts/RtsStartup.c
@@ -26,7 +26,8 @@
 #include "ThreadLabels.h"
 #include "sm/BlockAlloc.h"
 #include "Trace.h"
-#include "Stable.h"
+#include "StableName.h"
+#include "StablePtr.h"
 #include "StaticPtrTable.h"
 #include "Hash.h"
 #include "Profiling.h"
@@ -243,7 +244,10 @@ hs_init_ghc(int *argc, char **argv[], RtsConfig rts_config)
     initStorage();
 
     /* initialise the stable pointer table */
-    initStableTables();
+    initStablePtrTable();
+
+    /* initialise the stable name table */
+    initStableNameTable();
 
     /* Add some GC roots for things in the base package that the RTS
      * knows about.  We don't know whether these turn out to be CAFs
@@ -451,7 +455,10 @@ hs_exit_(bool wait_foreign)
     exitTopHandler();
 
     /* free the stable pointer table */
-    exitStableTables();
+    exitStablePtrTable();
+
+    /* free the stable name table */
+    exitStableNameTable();
 
 #if defined(DEBUG)
     /* free the thread label table */