add Outputable instance for OccIfaceEq

[ghc-hetmet.git] / rts / RaiseAsync.c

diff --git a/rts/RaiseAsync.c b/rts/RaiseAsync.c
index d555953..73c4429 100644 (file)
--- a/rts/RaiseAsync.c
+++ b/rts/RaiseAsync.c
@@ -17,6 +17,7 @@
 #include "Updates.h"
 #include "STM.h"
 #include "Sanity.h"
+#include "Profiling.h"
 #if defined(mingw32_HOST_OS)
 #include "win32/IOManager.h"
 #endif
@@ -282,7 +283,13 @@ check_target:
 
        // ASSUMPTION: tso->block_info must always point to a
        // closure.  In the threaded RTS it does.
-       if (get_itbl(mvar)->type != MVAR) goto retry;
+        switch (get_itbl(mvar)->type) {
+        case MVAR_CLEAN:
+        case MVAR_DIRTY:
+            break;
+        default:
+            goto retry;
+        }
 
        info = lockClosure((StgClosure *)mvar);
 
@@ -496,9 +503,11 @@ throwToReleaseTarget (void *tso)
    queue, but not perform any throwTo() immediately.  This might be
    more appropriate when the target thread is the one actually running
    (see Exception.cmm).
+
+   Returns: non-zero if an exception was raised, zero otherwise.
    -------------------------------------------------------------------------- */
 
-void
+int
 maybePerformBlockedException (Capability *cap, StgTSO *tso)
 {
     StgTSO *source;
@@ -514,7 +523,7 @@ maybePerformBlockedException (Capability *cap, StgTSO *tso)
        // locked it.
        if (tso->blocked_exceptions == END_TSO_QUEUE) {
            unlockTSO(tso);
-           return;
+           return 0;
        }
 
        // We unblock just the first thread on the queue, and perform
@@ -524,7 +533,9 @@ maybePerformBlockedException (Capability *cap, StgTSO *tso)
        tso->blocked_exceptions = unblockOne_(cap, source, 
                                              rtsFalse/*no migrate*/);
        unlockTSO(tso);
+        return 1;
     }
+    return 0;
 }
 
 void
@@ -842,6 +853,18 @@ raiseAsync(Capability *cap, StgTSO *tso, StgClosure *exception,
     debugTrace(DEBUG_sched,
               "raising exception in thread %ld.", (long)tso->id);
     
+#if defined(PROFILING)
+    /* 
+     * Debugging tool: on raising an  exception, show where we are.
+     * See also Exception.cmm:raisezh_fast.
+     * This wasn't done for asynchronous exceptions originally; see #1450 
+     */
+    if (RtsFlags.ProfFlags.showCCSOnException)
+    {
+        fprintCCS_stderr(tso->prof.CCCS);
+    }
+#endif
+
     // mark it dirty; we're about to change its stack.
     dirtyTSO(tso);
 
@@ -938,10 +961,12 @@ raiseAsync(Capability *cap, StgTSO *tso, StgClosure *exception,
        }
 
        case STOP_FRAME:
+       {
            // We've stripped the entire stack, the thread is now dead.
            tso->what_next = ThreadKilled;
            tso->sp = frame + sizeofW(StgStopFrame);
            return;
+       }
 
        case CATCH_FRAME:
            // If we find a CATCH_FRAME, and we've got an exception to raise,
@@ -1013,15 +1038,17 @@ raiseAsync(Capability *cap, StgTSO *tso, StgClosure *exception,
            // whether the transaction is valid or not because its
            // possible validity cannot have caused the exception
            // and will not be visible after the abort.
-           debugTrace(DEBUG_stm, 
-                      "found atomically block delivering async exception");
 
+               {
             StgTRecHeader *trec = tso -> trec;
             StgTRecHeader *outer = stmGetEnclosingTRec(trec);
+           debugTrace(DEBUG_stm, 
+                      "found atomically block delivering async exception");
             stmAbortTransaction(cap, trec);
            stmFreeAbortedTRec(cap, trec);
             tso -> trec = outer;
            break;
+           };
            
        default:
            break;