+#include "Windows/WindowsSupport.h"
+
+// On Windows, we can make use of vectored exception handling to
+// catch most crashing situations. Note that this does mean
+// we will be alerted of exceptions *before* structured exception
+// handling has the opportunity to catch it. But that isn't likely
+// to cause problems because nowhere in the project is SEH being
+// used.
+//
+// Vectored exception handling is built on top of SEH, and so it
+// works on a per-thread basis.
+//
+// The vectored exception handler functionality was added in Windows
+// XP, so if support for older versions of Windows is required,
+// it will have to be added.
+//
+// If we want to support as far back as Win2k, we could use the
+// SetUnhandledExceptionFilter API, but there's a risk of that
+// being entirely overwritten (it's not a chain).
+
+static LONG CALLBACK ExceptionHandler(PEXCEPTION_POINTERS ExceptionInfo)
+{
+ // Lookup the current thread local recovery object.
+ const CrashRecoveryContextImpl *CRCI = CurrentContext->get();
+
+ if (!CRCI) {
+ // Something has gone horribly wrong, so let's just tell everyone
+ // to keep searching
+ CrashRecoveryContext::Disable();
+ return EXCEPTION_CONTINUE_SEARCH;
+ }
+
+ // TODO: We can capture the stack backtrace here and store it on the
+ // implementation if we so choose.
+
+ // Handle the crash
+ const_cast<CrashRecoveryContextImpl*>(CRCI)->HandleCrash();
+
+ // Note that we don't actually get here because HandleCrash calls
+ // longjmp, which means the HandleCrash function never returns.
+ llvm_unreachable("Handled the crash, should have longjmp'ed out of here");
+}
+
+// Because the Enable and Disable calls are static, it means that
+// there may not actually be an Impl available, or even a current
+// CrashRecoveryContext at all. So we make use of a thread-local
+// exception table. The handles contained in here will either be
+// non-NULL, valid VEH handles, or NULL.
+static sys::ThreadLocal<const void> sCurrentExceptionHandle;