[libcxxabi] r248108 - EH: fix register usage for SjLj

[Saleem Abdulrasool via cfe-commits]

Author: compnerd
Date: Sat Sep 19 21:08:31 2015
New Revision: 248108

URL: http://llvm.org/viewvc/llvm-project?rev=248108&view=rev
Log:
EH: fix register usage for SjLj

When using SjLj EH, do not use __builtin_eh_return_regno, map directly to the
ID.  This would work on some targets, particularly those where the non-SjLj EH
personality used the same register mapping (0 -> 0, 1 -> 1).  However, this is
not guaranteed.  Avoiding the use of the builtin enables the use of libc++ with
SjLj EH on all targets.

Modified:
    libcxxabi/trunk/src/cxa_personality.cpp

Modified: libcxxabi/trunk/src/cxa_personality.cpp
URL: http://llvm.org/viewvc/llvm-project/libcxxabi/trunk/src/cxa_personality.cpp?rev=248108&r1=248107&r2=248108&view=diff
==============================================================================
--- libcxxabi/trunk/src/cxa_personality.cpp (original)
+++ libcxxabi/trunk/src/cxa_personality.cpp Sat Sep 19 21:08:31 2015
@@ -514,11 +514,14 @@ void
 set_registers(_Unwind_Exception* unwind_exception, _Unwind_Context* context,
               const scan_results& results)
 {
-    _Unwind_SetGR(context, __builtin_eh_return_data_regno(0),
-                                 reinterpret_cast<uintptr_t>(unwind_exception));
-    _Unwind_SetGR(context, __builtin_eh_return_data_regno(1),
-                                    static_cast<uintptr_t>(results.ttypeIndex));
-    _Unwind_SetIP(context, results.landingPad);
+#if defined(__USING_SJLJ_EXCEPTIONS__)
+#define __builtin_eh_return_data_regno(regno) regno
+#endif
+  _Unwind_SetGR(context, __builtin_eh_return_data_regno(0),
+                reinterpret_cast<uintptr_t>(unwind_exception));
+  _Unwind_SetGR(context, __builtin_eh_return_data_regno(1),
+                static_cast<uintptr_t>(results.ttypeIndex));
+  _Unwind_SetIP(context, results.landingPad);
 }
 
 /*