Initial checking of C++ exception handling library

llvm-svn: 8146
diff --git a/llvm/runtime/GCCLibraries/crtend/Exception.h b/llvm/runtime/GCCLibraries/crtend/Exception.h
new file mode 100644
index 0000000..a0357b5
--- /dev/null
+++ b/llvm/runtime/GCCLibraries/crtend/Exception.h
@@ -0,0 +1,49 @@
+//===- exception.h - Generic language-independent exceptions ----*- C++ -*-===//
+//
+// This file defines the the shared data structures used by all language
+// specific exception handling runtime libraries.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef EXCEPTION_H
+#define EXCEPTION_H
+
+typedef struct llvm_exception {
+  // ExceptionDestructor - This call-back function is used to destroy the
+  // current exception, without requiring the caller to know what the concrete
+  // exception type is.
+  //
+  void (*ExceptionDestructor)(struct llvm_exception *);
+  
+  // ExceptionType - This field identifies what runtime library this exception
+  // came from.  Currently defined values are:
+  //     0 - Error
+  //     1 - longjmp exception (see longjmp-exception.c)
+  //     2 - C++ exception (see c++-exception.c)
+  //
+  unsigned ExceptionType;
+
+  // Next - This points to the next exception in the current stack.
+  struct llvm_exception *Next;
+
+  // HandlerCount - This is a count of the number of handlers which have
+  // currently caught this exception.  If the handler is caught and this number
+  // falls to zero, the exception is destroyed.
+  //
+  unsigned HandlerCount;
+} llvm_exception;
+
+enum {
+  ErrorException   = 0,
+  LongjmpException = 1,
+  CXXException     = 2,
+};
+
+// Language independent exception handling API...
+//
+extern "C" {
+  bool __llvm_eh_has_uncaught_exception(void);
+  void *__llvm_eh_current_uncaught_exception_type(unsigned HandlerType);
+}
+
+#endif