On 08.01.15 17:27, Richard Earnshaw wrote:
On 29/12/14 18:44, Andreas Tobler wrote:
All,
here is the third attempt to support ARM with FreeBSD.
In the meantime we found another issue in the unwinder where I had to
adapt some stuff.
The unwind_phase2_forced function in libgcc calls a stop_fn function.
This stop_fn is in FreeBSD's libthr implementation and is called
thread_unwind_stop. This thread_unwind_stop is a generic function used
on all FreeBSD archs.
The issue is now that this thread_unwind_stop expects a double int for
the exception_class, like on every other arch. For ARM EABI this
exception_class is an array of char which is passed in one register as
pointer vs. two registers for a double int.
To solve this issue we defined the exception_class as double integer for
FreeBSD.
This adaptation reduced the failure count in libstdc++ by about 40 fails.
I build and test this port on a regular basis and I post the results to
the usual place.
...
Umm, sorry, just seen this update to the previous patch.
The changes to the exception unwinding look a bit more involved. Could
you separate that out into a separate patch, so that it's easier to see
what you're changing?
Ok, here the mentioned part as separate diff. The comments are above.
The CL below :)
Thank you very much!
Andreas
gcc:
* ginclude/unwind-arm-common.h (_Uwind_Control_Block): Define
exception_class as double integer for FreeBSD ARM.
(_Unwind_Exception): Define _Unwind_Exception_Class as double integer
for FreeBSD ARM.
libstc++-v3:
* libsupc++/unwind-cxx.h (__is_gxx_exception_class,
__is_dependent_exception): Exclude FreeBSD ARM from the
__ARM_EABI_UNWINDER__ ifdef.
Index: gcc/ginclude/unwind-arm-common.h
===================================================================
--- gcc/ginclude/unwind-arm-common.h (revision 219357)
+++ gcc/ginclude/unwind-arm-common.h (working copy)
@@ -82,7 +82,11 @@
struct _Unwind_Control_Block
{
+#ifdef __FreeBSD__
+ unsigned exception_class __attribute__((__mode__(__DI__)));
+#else
char exception_class[8];
+#endif
void (*exception_cleanup)(_Unwind_Reason_Code, _Unwind_Control_Block *);
/* Unwinder cache, private fields for the unwinder's use */
struct
@@ -181,7 +185,11 @@
/* Support functions for the PR. */
#define _Unwind_Exception _Unwind_Control_Block
+#ifdef __FreeBSD__
+ typedef unsigned _Unwind_Exception_Class __attribute__((__mode__(__DI__)));
+#else
typedef char _Unwind_Exception_Class[8];
+#endif
void * _Unwind_GetLanguageSpecificData (_Unwind_Context *);
_Unwind_Ptr _Unwind_GetRegionStart (_Unwind_Context *);
Index: libstdc++-v3/libsupc++/unwind-cxx.h
===================================================================
--- libstdc++-v3/libsupc++/unwind-cxx.h (revision 219357)
+++ libstdc++-v3/libsupc++/unwind-cxx.h (working copy)
@@ -235,7 +235,7 @@
return reinterpret_cast<__cxa_dependent_exception *>(exc + 1) - 1;
}
-#ifdef __ARM_EABI_UNWINDER__
+#if defined (__ARM_EABI_UNWINDER__) && !defined (__FreeBSD__)
static inline bool
__is_gxx_exception_class(_Unwind_Exception_Class c)
{
@@ -309,13 +309,7 @@
c[6] = 'R';
c[7] = '\0';
}
-
-static inline void*
-__gxx_caught_object(_Unwind_Exception* eo)
-{
- return (void*)eo->barrier_cache.bitpattern[0];
-}
-#else // !__ARM_EABI_UNWINDER__
+#else // !__ARM_EABI_UNWINDER__ || __FreeBSD__
// This is the primary exception class we report -- "GNUCC++\0".
const _Unwind_Exception_Class __gxx_primary_exception_class
= ((((((((_Unwind_Exception_Class) 'G'
@@ -339,6 +333,16 @@
<< 8 | (_Unwind_Exception_Class) '+')
<< 8 | (_Unwind_Exception_Class) '\x01');
+const _Unwind_Exception_Class __gxx_forced_unwind_class
+= ((((((((_Unwind_Exception_Class) 'G'
+ << 8 | (_Unwind_Exception_Class) 'N')
+ << 8 | (_Unwind_Exception_Class) 'U')
+ << 8 | (_Unwind_Exception_Class) 'C')
+ << 8 | (_Unwind_Exception_Class) 'F')
+ << 8 | (_Unwind_Exception_Class) 'O')
+ << 8 | (_Unwind_Exception_Class) 'R')
+ << 8 | (_Unwind_Exception_Class) '\0');
+
static inline bool
__is_gxx_exception_class(_Unwind_Exception_Class c)
{
@@ -346,6 +350,12 @@
|| c == __gxx_dependent_exception_class;
}
+static inline bool
+__is_gxx_forced_unwind_class(_Unwind_Exception_Class c)
+{
+ return c == __gxx_forced_unwind_class;
+}
+
// Only checks for primary or dependent, but not that it is a C++ exception at
// all.
static inline bool
@@ -357,7 +367,18 @@
#define __GXX_INIT_PRIMARY_EXCEPTION_CLASS(c) c = __gxx_primary_exception_class
#define __GXX_INIT_DEPENDENT_EXCEPTION_CLASS(c) \
c = __gxx_dependent_exception_class
+#define __GXX_INIT_FORCED_UNWIND_CLASS(c) c = __gxx_forced_unwind_class
+#endif // __ARM_EABI_UNWINDER__ && !__FreeBSD__
+#ifdef __ARM_EABI_UNWINDER__
+static inline void*
+__gxx_caught_object(_Unwind_Exception* eo)
+{
+ return (void*)eo->barrier_cache.bitpattern[0];
+}
+
+#else // !__ARM_EABI_UNWINDER__
+
// GNU C++ personality routine, Version 0.
extern "C" _Unwind_Reason_Code __gxx_personality_v0
(int, _Unwind_Action, _Unwind_Exception_Class,
