Changeset 485

Timestamp:

01/08/11 15:45:57 (14 years ago)

Author:

Don Clugston

Message:

Added exception frame handling for debugging.

Files:

• trunk/src/rt/deh.d (modified) (1 diff)

trunk/src/rt/deh.d

@@ -190 +190 @@
-}
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-/+
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-Implementation of Structured Exception Handling in DMD-Windows
-
-Every function which uses exception handling (a 'frame') has a thunk created
-for it. This thunk is the 'language-specific handler'.
-The thunks are created in the DMD backend, in nteh_framehandler() in nteh.c.
-These thunks are of the form:
-
+ 
-      JMP     __d_framehandler
-FS:[0] contains a singly linked list of all active handlers (they'll all be
-thunks). The list is created on the stack. 
-At the end of this list is _except_handler3, a function in the DMC library.
-
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-
-extern(C)
-EXCEPTION_DISPOSITION _except_handler3(EXCEPTION_RECORD *eRecord,
-    DEstablisherFrame * frame,CONTEXT *context,void *dispatchercontext);
-
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-
-Documentation of Windows SEH is hard to find. Here is a brief explanation:
-
-When an exception is raised, the OS calls each handler in the FS:[0] list in
-turn, looking for a catch block. It continues moving down the list, as long as
-each handler indicates that it has not caught the exception. When a handler is
-ready to catch the exception, it calls the OS function RtlUnwind.
-This calls each function in the FS:[0] list again, this time indicating that it
-is a 'unwind' call. All of the intervening finally blocks are run at this time.
-The complicated case is a CollidedException, which happens when a finally block