Remove some extraneous whitespace

[ghc-hetmet.git] / rts / Exception.cmm

diff --git a/rts/Exception.cmm b/rts/Exception.cmm
index cd3f2bc..f85e2e9 100644 (file)
--- a/rts/Exception.cmm
+++ b/rts/Exception.cmm
@@ -21,12 +21,12 @@ import ghczmprim_GHCziBool_True_closure;
    A thread can request that asynchronous exceptions not be delivered
    ("blocked") for the duration of an I/O computation.  The primitive
    
    A thread can request that asynchronous exceptions not be delivered
    ("blocked") for the duration of an I/O computation.  The primitive
    

-       blockAsyncExceptions# :: IO a -> IO a
+       maskAsyncExceptions# :: IO a -> IO a

 
    is used for this purpose.  During a blocked section, asynchronous
    exceptions may be unblocked again temporarily:
 
 
    is used for this purpose.  During a blocked section, asynchronous
    exceptions may be unblocked again temporarily:
 

-       unblockAsyncExceptions# :: IO a -> IO a
+       unmaskAsyncExceptions# :: IO a -> IO a

 
    Furthermore, asynchronous exceptions are blocked automatically during
    the execution of an exception handler.  Both of these primitives
 
    Furthermore, asynchronous exceptions are blocked automatically during
    the execution of an exception handler.  Both of these primitives

@@ -39,34 +39,33 @@ import ghczmprim_GHCziBool_True_closure;
    the threads waiting to deliver exceptions to that thread.
 
    NB. there's a bug in here.  If a thread is inside an
    the threads waiting to deliver exceptions to that thread.
 
    NB. there's a bug in here.  If a thread is inside an

-   unsafePerformIO, and inside blockAsyncExceptions# (there is an
-   unblockAsyncExceptions_ret on the stack), and it is blocked in an
+   unsafePerformIO, and inside maskAsyncExceptions# (there is an
+   unmaskAsyncExceptions_ret on the stack), and it is blocked in an

    interruptible operation, and it receives an exception, then the
    unsafePerformIO thunk will be updated with a stack object
    interruptible operation, and it receives an exception, then the
    unsafePerformIO thunk will be updated with a stack object

-   containing the unblockAsyncExceptions_ret frame.  Later, when
+   containing the unmaskAsyncExceptions_ret frame.  Later, when

    someone else evaluates this thunk, the blocked exception state is
    not restored.
 
    -------------------------------------------------------------------------- */
 
    someone else evaluates this thunk, the blocked exception state is
    not restored.
 
    -------------------------------------------------------------------------- */
 

-STRING(stg_unblockAsync_err_str, "unblockAsyncExceptions#_ret")

 
 

-INFO_TABLE_RET( stg_unblockAsyncExceptionszh_ret, RET_SMALL )
+INFO_TABLE_RET(stg_unmaskAsyncExceptionszh_ret, RET_SMALL)

 {
     CInt r;
 
 {
     CInt r;
 

-    StgTSO_flags(CurrentTSO) = StgTSO_flags(CurrentTSO) & 
-       ~(TSO_BLOCKEX::I32|TSO_INTERRUPTIBLE::I32);
+    StgTSO_flags(CurrentTSO) = %lobits32(
+      TO_W_(StgTSO_flags(CurrentTSO)) & ~(TSO_BLOCKEX|TSO_INTERRUPTIBLE));

 
     /* Eagerly raise a blocked exception, if there is one */
     if (StgTSO_blocked_exceptions(CurrentTSO) != END_TSO_QUEUE) {
 
     /* Eagerly raise a blocked exception, if there is one */
     if (StgTSO_blocked_exceptions(CurrentTSO) != END_TSO_QUEUE) {

+
+        STK_CHK_GEN( WDS(2), R1_PTR, stg_unmaskAsyncExceptionszh_ret_info);

         /* 
          * We have to be very careful here, as in killThread#, since
          * we are about to raise an async exception in the current
          * thread, which might result in the thread being killed.
          */
         /* 
          * We have to be very careful here, as in killThread#, since
          * we are about to raise an async exception in the current
          * thread, which might result in the thread being killed.
          */

-
-        STK_CHK_GEN( WDS(2), R1_PTR, stg_unblockAsyncExceptionszh_ret_info);

         Sp_adj(-2);
         Sp(1) = R1;
         Sp(0) = stg_gc_unpt_r1_info;
         Sp_adj(-2);
         Sp(1) = R1;
         Sp(0) = stg_gc_unpt_r1_info;

@@ -97,44 +96,94 @@ INFO_TABLE_RET( stg_unblockAsyncExceptionszh_ret, RET_SMALL )
     jump %ENTRY_CODE(Sp(0));
 }
 
     jump %ENTRY_CODE(Sp(0));
 }
 

-INFO_TABLE_RET( stg_blockAsyncExceptionszh_ret, RET_SMALL )
+INFO_TABLE_RET(stg_maskAsyncExceptionszh_ret, RET_SMALL)

 {
     StgTSO_flags(CurrentTSO) = 
 {
     StgTSO_flags(CurrentTSO) = 

-       StgTSO_flags(CurrentTSO) | TSO_BLOCKEX::I32 | TSO_INTERRUPTIBLE::I32;
+       %lobits32(
+        TO_W_(StgTSO_flags(CurrentTSO))
+          | TSO_BLOCKEX | TSO_INTERRUPTIBLE
+      );

 
     Sp_adj(1);
     jump %ENTRY_CODE(Sp(0));
 }
 
 
     Sp_adj(1);
     jump %ENTRY_CODE(Sp(0));
 }
 

-stg_blockAsyncExceptionszh
+INFO_TABLE_RET(stg_maskUninterruptiblezh_ret, RET_SMALL)
+{
+    StgTSO_flags(CurrentTSO) = 
+       %lobits32(
+       (TO_W_(StgTSO_flags(CurrentTSO))
+          | TSO_BLOCKEX)
+          & ~TSO_INTERRUPTIBLE
+       );
+
+    Sp_adj(1);
+    jump %ENTRY_CODE(Sp(0));
+}
+
+stg_maskAsyncExceptionszh

 {
     /* Args: R1 :: IO a */
 {
     /* Args: R1 :: IO a */

-    STK_CHK_GEN( WDS(2)/* worst case */, R1_PTR, stg_blockAsyncExceptionszh);
+    STK_CHK_GEN( WDS(1)/* worst case */, R1_PTR, stg_maskAsyncExceptionszh);

 
     if ((TO_W_(StgTSO_flags(CurrentTSO)) & TSO_BLOCKEX) == 0) {
 
     if ((TO_W_(StgTSO_flags(CurrentTSO)) & TSO_BLOCKEX) == 0) {

-       
-       StgTSO_flags(CurrentTSO) = 
-          StgTSO_flags(CurrentTSO) | TSO_BLOCKEX::I32 | TSO_INTERRUPTIBLE::I32;
+        /* avoid growing the stack unnecessarily */
+        if (Sp(0) == stg_maskAsyncExceptionszh_ret_info) {
+            Sp_adj(1);
+        } else {
+            Sp_adj(-1);
+            Sp(0) = stg_unmaskAsyncExceptionszh_ret_info;
+        }
+    } else {
+        if ((TO_W_(StgTSO_flags(CurrentTSO)) & TSO_INTERRUPTIBLE) == 0) {
+            Sp_adj(-1);
+            Sp(0) = stg_maskUninterruptiblezh_ret_info;
+        }
+    }

 
 

-       /* avoid growing the stack unnecessarily */
-       if (Sp(0) == stg_blockAsyncExceptionszh_ret_info) {
-           Sp_adj(1);
-       } else {
-           Sp_adj(-1);
-           Sp(0) = stg_unblockAsyncExceptionszh_ret_info;
-       }
+    StgTSO_flags(CurrentTSO) = %lobits32(
+        TO_W_(StgTSO_flags(CurrentTSO)) | TSO_BLOCKEX | TSO_INTERRUPTIBLE);
+
+    TICK_UNKNOWN_CALL();
+    TICK_SLOW_CALL_v();
+    jump stg_ap_v_fast;
+}
+
+stg_maskUninterruptiblezh
+{
+    /* Args: R1 :: IO a */
+    STK_CHK_GEN( WDS(1)/* worst case */, R1_PTR, stg_maskAsyncExceptionszh);
+
+    if ((TO_W_(StgTSO_flags(CurrentTSO)) & TSO_BLOCKEX) == 0) {
+        /* avoid growing the stack unnecessarily */
+        if (Sp(0) == stg_maskUninterruptiblezh_ret_info) {
+            Sp_adj(1);
+        } else {
+            Sp_adj(-1);
+            Sp(0) = stg_unmaskAsyncExceptionszh_ret_info;
+        }
+    } else {
+        if ((TO_W_(StgTSO_flags(CurrentTSO)) & TSO_INTERRUPTIBLE) != 0) {
+            Sp_adj(-1);
+            Sp(0) = stg_maskAsyncExceptionszh_ret_info;
+        }

     }
     }

+
+    StgTSO_flags(CurrentTSO) = %lobits32(
+        (TO_W_(StgTSO_flags(CurrentTSO)) | TSO_BLOCKEX) & ~TSO_INTERRUPTIBLE);
+

     TICK_UNKNOWN_CALL();
     TICK_SLOW_CALL_v();
     jump stg_ap_v_fast;
 }
 
     TICK_UNKNOWN_CALL();
     TICK_SLOW_CALL_v();
     jump stg_ap_v_fast;
 }
 

-stg_unblockAsyncExceptionszh
+stg_unmaskAsyncExceptionszh

 {
     CInt r;
 {
     CInt r;

+    W_ level;

 
     /* Args: R1 :: IO a */
 
     /* Args: R1 :: IO a */

-    STK_CHK_GEN( WDS(4), R1_PTR, stg_unblockAsyncExceptionszh);
+    STK_CHK_GEN( WDS(4), R1_PTR, stg_unmaskAsyncExceptionszh);

     /* 4 words: one for the unblock frame, 3 for setting up the
      * stack to call maybePerformBlockedException() below.
      */
     /* 4 words: one for the unblock frame, 3 for setting up the
      * stack to call maybePerformBlockedException() below.
      */

@@ -142,17 +191,21 @@ stg_unblockAsyncExceptionszh
     /* If exceptions are already unblocked, there's nothing to do */
     if ((TO_W_(StgTSO_flags(CurrentTSO)) & TSO_BLOCKEX) != 0) {
 
     /* If exceptions are already unblocked, there's nothing to do */
     if ((TO_W_(StgTSO_flags(CurrentTSO)) & TSO_BLOCKEX) != 0) {
 

-       StgTSO_flags(CurrentTSO) = StgTSO_flags(CurrentTSO) & 
-          ~(TSO_BLOCKEX::I32|TSO_INTERRUPTIBLE::I32);
-

        /* avoid growing the stack unnecessarily */
        /* avoid growing the stack unnecessarily */

-       if (Sp(0) == stg_unblockAsyncExceptionszh_ret_info) {
+       if (Sp(0) == stg_unmaskAsyncExceptionszh_ret_info) {

            Sp_adj(1);
        } else {
            Sp_adj(-1);
            Sp_adj(1);
        } else {
            Sp_adj(-1);

-           Sp(0) = stg_blockAsyncExceptionszh_ret_info;
+            if ((TO_W_(StgTSO_flags(CurrentTSO)) & TSO_INTERRUPTIBLE) != 0) {
+                Sp(0) = stg_maskAsyncExceptionszh_ret_info;
+            } else {
+                Sp(0) = stg_maskUninterruptiblezh_ret_info;
+            }

        }
 
        }
 

+       StgTSO_flags(CurrentTSO) = %lobits32(
+            TO_W_(StgTSO_flags(CurrentTSO)) & ~(TSO_BLOCKEX|TSO_INTERRUPTIBLE));
+

         /* Eagerly raise a blocked exception, if there is one */
         if (StgTSO_blocked_exceptions(CurrentTSO) != END_TSO_QUEUE) {
             /* 
         /* Eagerly raise a blocked exception, if there is one */
         if (StgTSO_blocked_exceptions(CurrentTSO) != END_TSO_QUEUE) {
             /* 

@@ -195,14 +248,17 @@ stg_unblockAsyncExceptionszh
     jump stg_ap_v_fast;
 }
 
     jump stg_ap_v_fast;
 }
 

-stg_asyncExceptionsBlockedzh
+
+stg_getMaskingStatezh

 {
     /* args: none */
 {
     /* args: none */

-    if ((TO_W_(StgTSO_flags(CurrentTSO)) & TSO_BLOCKEX) != 0) {
-        RET_N(1);
-    } else {
-        RET_N(0);
-    }
+    /* 
+       returns: 0 == unmasked,
+                1 == masked, non-interruptible,
+                2 == masked, interruptible
+    */
+    RET_N(((TO_W_(StgTSO_flags(CurrentTSO)) & TSO_BLOCKEX) != 0) +
+          ((TO_W_(StgTSO_flags(CurrentTSO)) & TSO_INTERRUPTIBLE) != 0));

 }
 
 stg_killThreadzh
 }
 
 stg_killThreadzh

@@ -218,6 +274,8 @@ stg_killThreadzh
     
     /* Needs 3 words because throwToSingleThreaded uses some stack */
     STK_CHK_GEN( WDS(3), R1_PTR & R2_PTR, stg_killThreadzh);
     
     /* Needs 3 words because throwToSingleThreaded uses some stack */
     STK_CHK_GEN( WDS(3), R1_PTR & R2_PTR, stg_killThreadzh);

+    /* We call allocate in throwTo(), so better check for GC */
+    MAYBE_GC(R1_PTR & R2_PTR, stg_killThreadzh);

 
     /* 
      * We might have killed ourselves.  In which case, better be *very*
 
     /* 
      * We might have killed ourselves.  In which case, better be *very*

@@ -252,27 +310,22 @@ stg_killThreadzh
        }
     } else {
        W_ out;
        }
     } else {
        W_ out;

-       W_ retcode;
+       W_ msg;

        out = Sp - WDS(1); /* ok to re-use stack space here */
 
        out = Sp - WDS(1); /* ok to re-use stack space here */
 

-       (retcode) = foreign "C" throwTo(MyCapability() "ptr",
-                                     CurrentTSO "ptr",
-                                     target "ptr",
-                                     exception "ptr",
-                                     out "ptr") [R1,R2];
+       (msg) = foreign "C" throwTo(MyCapability() "ptr",
+                                    CurrentTSO "ptr",
+                                    target "ptr",
+                                    exception "ptr") [R1,R2];

        
        

-       switch [THROWTO_SUCCESS .. THROWTO_BLOCKED] (retcode) {
-
-       case THROWTO_SUCCESS: {
+        if (msg == NULL) {

            jump %ENTRY_CODE(Sp(0));
            jump %ENTRY_CODE(Sp(0));

-       }
-
-       case THROWTO_BLOCKED: {
-           R3 = W_[out];
-           // we must block, and call throwToReleaseTarget() before returning
+       } else {
+            StgTSO_why_blocked(CurrentTSO) = BlockedOnMsgThrowTo;
+            StgTSO_block_info(CurrentTSO) = msg;
+           // we must block, and unlock the message before returning

            jump stg_block_throwto;
        }
            jump stg_block_throwto;
        }

-       }

     }
 }
 
     }
 }
 

@@ -324,7 +377,8 @@ stg_catchzh
     SET_HDR(Sp,stg_catch_frame_info,W_[CCCS]);
     
     StgCatchFrame_handler(Sp) = R2;
     SET_HDR(Sp,stg_catch_frame_info,W_[CCCS]);
     
     StgCatchFrame_handler(Sp) = R2;

-    StgCatchFrame_exceptions_blocked(Sp) = TO_W_(StgTSO_flags(CurrentTSO)) & TSO_BLOCKEX;
+    StgCatchFrame_exceptions_blocked(Sp) = 
+        TO_W_(StgTSO_flags(CurrentTSO)) & (TSO_BLOCKEX | TSO_INTERRUPTIBLE);

     TICK_CATCHF_PUSHED();
 
     /* Apply R1 to the realworld token */
     TICK_CATCHF_PUSHED();
 
     /* Apply R1 to the realworld token */

@@ -398,7 +452,7 @@ retry_pop_stack:
       W_ r;
       trec = StgTSO_trec(CurrentTSO);
       (r) = foreign "C" stmValidateNestOfTransactions(trec "ptr") [];
       W_ r;
       trec = StgTSO_trec(CurrentTSO);
       (r) = foreign "C" stmValidateNestOfTransactions(trec "ptr") [];

-      ("ptr" outer) = foreign "C" stmGetEnclosingTRec(trec "ptr") [];
+      outer  = StgTRecHeader_enclosing_trec(trec);

       foreign "C" stmAbortTransaction(MyCapability() "ptr", trec "ptr") [];
       foreign "C" stmFreeAbortedTRec(MyCapability() "ptr", trec "ptr") [];
 
       foreign "C" stmAbortTransaction(MyCapability() "ptr", trec "ptr") [];
       foreign "C" stmFreeAbortedTRec(MyCapability() "ptr", trec "ptr") [];
 

@@ -440,10 +494,9 @@ retry_pop_stack:
             // be per-thread.
             CInt[rts_stop_on_exception] = 0;
             ("ptr" ioAction) = foreign "C" deRefStablePtr (W_[rts_breakpoint_io_action] "ptr") [];
             // be per-thread.
             CInt[rts_stop_on_exception] = 0;
             ("ptr" ioAction) = foreign "C" deRefStablePtr (W_[rts_breakpoint_io_action] "ptr") [];

-            Sp = Sp - WDS(7);
-            Sp(6) = exception;
-            Sp(5) = stg_raise_ret_info;
-            Sp(4) = stg_noforceIO_info;    // required for unregisterised
+            Sp = Sp - WDS(6);
+            Sp(5) = exception;
+            Sp(4) = stg_raise_ret_info;

             Sp(3) = exception;             // the AP_STACK
             Sp(2) = ghczmprim_GHCziBool_True_closure; // dummy breakpoint info
             Sp(1) = ghczmprim_GHCziBool_True_closure; // True <=> a breakpoint
             Sp(3) = exception;             // the AP_STACK
             Sp(2) = ghczmprim_GHCziBool_True_closure; // dummy breakpoint info
             Sp(1) = ghczmprim_GHCziBool_True_closure; // True <=> a breakpoint

@@ -482,7 +535,7 @@ retry_pop_stack:
      *
      * If exceptions were unblocked, arrange that they are unblocked
      * again after executing the handler by pushing an
      *
      * If exceptions were unblocked, arrange that they are unblocked
      * again after executing the handler by pushing an

-     * unblockAsyncExceptions_ret stack frame.
+     * unmaskAsyncExceptions_ret stack frame.

      *
      * If we've reached an STM catch frame then roll back the nested
      * transaction we were using.
      *
      * If we've reached an STM catch frame then roll back the nested
      * transaction we were using.

@@ -491,14 +544,14 @@ retry_pop_stack:
     frame = Sp;
     if (frame_type == CATCH_FRAME) {
       Sp = Sp + SIZEOF_StgCatchFrame;
     frame = Sp;
     if (frame_type == CATCH_FRAME) {
       Sp = Sp + SIZEOF_StgCatchFrame;

-      if (StgCatchFrame_exceptions_blocked(frame) == 0) {
-        Sp_adj(-1);
-        Sp(0) = stg_unblockAsyncExceptionszh_ret_info;
+      if ((StgCatchFrame_exceptions_blocked(frame) & TSO_BLOCKEX) == 0) {
+          Sp_adj(-1);
+          Sp(0) = stg_unmaskAsyncExceptionszh_ret_info;

       }
     } else {
       W_ trec, outer;
       trec = StgTSO_trec(CurrentTSO);
       }
     } else {
       W_ trec, outer;
       trec = StgTSO_trec(CurrentTSO);

-      ("ptr" outer) = foreign "C" stmGetEnclosingTRec(trec "ptr") [];
+      outer  = StgTRecHeader_enclosing_trec(trec);

       foreign "C" stmAbortTransaction(MyCapability() "ptr", trec "ptr") [];
       foreign "C" stmFreeAbortedTRec(MyCapability() "ptr", trec "ptr") [];
       StgTSO_trec(CurrentTSO) = outer;
       foreign "C" stmAbortTransaction(MyCapability() "ptr", trec "ptr") [];
       foreign "C" stmFreeAbortedTRec(MyCapability() "ptr", trec "ptr") [];
       StgTSO_trec(CurrentTSO) = outer;

@@ -506,9 +559,18 @@ retry_pop_stack:
     }
 
     /* Ensure that async excpetions are blocked when running the handler.
     }
 
     /* Ensure that async excpetions are blocked when running the handler.

+     * The interruptible state is inherited from the context of the
+     * catch frame.

     */
     */

-    StgTSO_flags(CurrentTSO) = 
-       StgTSO_flags(CurrentTSO) | TSO_BLOCKEX::I32 | TSO_INTERRUPTIBLE::I32;
+    StgTSO_flags(CurrentTSO) = %lobits32(
+       TO_W_(StgTSO_flags(CurrentTSO)) | TSO_BLOCKEX);
+    if ((StgCatchFrame_exceptions_blocked(frame) & TSO_INTERRUPTIBLE) == 0) {
+        StgTSO_flags(CurrentTSO) = %lobits32(
+            TO_W_(StgTSO_flags(CurrentTSO)) & ~TSO_INTERRUPTIBLE);
+    } else {
+        StgTSO_flags(CurrentTSO) = %lobits32(
+            TO_W_(StgTSO_flags(CurrentTSO)) | TSO_INTERRUPTIBLE);
+    }

 
     /* Call the handler, passing the exception value and a realworld
      * token as arguments.
 
     /* Call the handler, passing the exception value and a realworld
      * token as arguments.