2009-10-24 Zoltan Varga <vargaz@gmail.com>
[mono.git] / mono / mini / exceptions-s390.c
index 2e3bb3faf3fb10e06af7c17ad3c0c8642eb1e715..2e41bb787e4c6f3456e75e066aa1fb46c0b243ca 100644 (file)
 /*                 D e f i n e s                                    */
 /*------------------------------------------------------------------*/
 
-#define MONO_CONTEXT_SET_IP(ctx,ip)                                    \
-       do {                                                            \
-               (ctx)->uc_mcontext.gregs[14] = (unsigned long)ip;       \
-               (ctx)->uc_mcontext.psw.addr = (unsigned long)ip;        \
-       } while (0); 
-
-#define MONO_CONTEXT_SET_BP(ctx,bp)                                    \
-       do {                                                            \
-               (ctx)->uc_mcontext.gregs[15] = (unsigned long)bp;       \
-               (ctx)->uc_stack.ss_sp        = (unsigned long)bp;       \
-       } while (0); 
-
-#define MONO_CONTEXT_GET_IP(ctx) context_get_ip ((ctx))
-#define MONO_CONTEXT_GET_BP(ctx) ((gpointer)((ctx)->uc_mcontext.gregs[15]))
-
-/* disable this for now */
-#undef MONO_USE_EXC_TABLES
-
 #define S390_CALLFILTER_INTREGS        S390_MINIMAL_STACK_SIZE
 #define S390_CALLFILTER_FLTREGS                S390_CALLFILTER_INTREGS+(16*sizeof(gulong))
 #define S390_CALLFILTER_ACCREGS                S390_CALLFILTER_FLTREGS+(16*sizeof(gdouble))
 
 #define S390_THROWSTACK_ACCPRM         S390_MINIMAL_STACK_SIZE
 #define S390_THROWSTACK_FPCPRM         S390_THROWSTACK_ACCPRM+sizeof(gpointer)
-#define S390_THROWSTACK_INTREGS                S390_THROWSTACK_FPCPRM+sizeof(gulong)
+#define S390_THROWSTACK_RETHROW                S390_THROWSTACK_FPCPRM+sizeof(gulong)
+#define S390_THROWSTACK_INTREGS                S390_THROWSTACK_RETHROW+sizeof(gboolean)
 #define S390_THROWSTACK_FLTREGS                S390_THROWSTACK_INTREGS+(16*sizeof(gulong))
 #define S390_THROWSTACK_ACCREGS                S390_THROWSTACK_FLTREGS+(16*sizeof(gdouble))
 #define S390_THROWSTACK_SIZE           (S390_THROWSTACK_ACCREGS+(16*sizeof(gulong)))
 
+#define SZ_THROW       384
+
 /*========================= End of Defines =========================*/
 
 /*------------------------------------------------------------------*/
@@ -60,6 +45,7 @@
 #include <glib.h>
 #include <signal.h>
 #include <string.h>
+#include <ucontext.h>
 
 #include <mono/arch/s390/s390-codegen.h>
 #include <mono/metadata/appdomain.h>
 
 /*========================= End of Includes ========================*/
 
-/*------------------------------------------------------------------*/
-/*                 T y p e d e f s                                  */
-/*------------------------------------------------------------------*/
-
-typedef struct
-{
-  void *prev;
-  void *unused[5];
-  void *reg6;
-  void *reg7;
-  void *reg8;
-  void *reg9;
-  void *reg10;
-  void *reg11;
-  void *reg12;
-  void *reg13;
-  void *return_address;
-} MonoS390StackFrame;
-
-#ifdef MONO_USE_EXC_TABLES
-
-/*************************************/
-/*    STACK UNWINDING STUFF          */
-/*************************************/
-
-/* These definitions are from unwind-dw2.c in glibc 2.2.5 */
-
-/* For x86 */
-#define DWARF_FRAME_REGISTERS 17
-
-typedef struct frame_state
-{
-  void *cfa;
-  void *eh_ptr;
-  long cfa_offset;
-  long args_size;
-  long reg_or_offset[DWARF_FRAME_REGISTERS+1];
-  unsigned short cfa_reg;
-  unsigned short retaddr_column;
-  char saved[DWARF_FRAME_REGISTERS+1];
-} frame_state;
-
-typedef struct frame_state * (*framesf) (void *, struct frame_state *);
-
-#endif
-
-/*========================= End of Typedefs ========================*/
-
 /*------------------------------------------------------------------*/
 /*                   P r o t o t y p e s                            */
 /*------------------------------------------------------------------*/
@@ -136,79 +74,8 @@ gboolean mono_arch_handle_exception (void     *ctx,
 /*                 G l o b a l   V a r i a b l e s                  */
 /*------------------------------------------------------------------*/
 
-#ifdef MONO_USE_EXC_TABLES
-
-static framesf frame_state_for = NULL;
-
-static gboolean inited = FALSE;
-
-typedef char ** (*get_backtrace_symbols_type) (void *__const *__array, int __size);
-
-static get_backtrace_symbols_type get_backtrace_symbols = NULL;
-
-#endif
-
 /*====================== End of Global Variables ===================*/
 
-/*------------------------------------------------------------------*/
-/*                                                                  */
-/* Name                - context_get_ip                                    */
-/*                                                                  */
-/* Function    - Extract the current instruction address from the  */
-/*               context.                                          */
-/*                                                                 */
-/*------------------------------------------------------------------*/
-
-static inline gpointer 
-context_get_ip (MonoContext *ctx) 
-{
-       gpointer ip;
-
-       ip = (gpointer) ((gint32) (ctx->uc_mcontext.psw.addr) & 0x7fffffff);
-       return ip;
-}
-
-/*========================= End of Function ========================*/
-
-#ifdef MONO_USE_EXC_TABLES
-
-/*------------------------------------------------------------------*/
-/*                                                                  */
-/* Name                - init_frame_state_for                              */
-/*                                                                  */
-/* Function    - Load the __frame_state_for from libc.             */
-/*                There are two versions of __frame_state_for: one  */ 
-/*               in libgcc.a and the other in glibc.so. We need    */
-/*                the version from glibc. For more information, see:*/
-/*                http://gcc.gnu.org/ml/gcc/2002-08/msg00192.html   */
-/*                                                                  */
-/*------------------------------------------------------------------*/
-
-static void
-init_frame_state_for (void)
-{
-       GModule *module;
-
-       if ((module = g_module_open ("libc.so.6", G_MODULE_BIND_LAZY))) {
-       
-               if (!g_module_symbol (module, "__frame_state_for", (gpointer*)&frame_state_for))
-                       frame_state_for = NULL;
-
-               if (!g_module_symbol (module, "backtrace_symbols", (gpointer*)&get_backtrace_symbols)) {
-                       get_backtrace_symbols = NULL;
-                       frame_state_for = NULL;
-               }
-
-               g_module_close (module);
-       }
-
-       inited = TRUE;
-}
-
-/*========================= End of Function ========================*/
-
-#endif
-
 /*------------------------------------------------------------------*/
 /*                                                                  */
 /* Name                - mono_arch_has_unwind_info                         */
@@ -221,154 +88,14 @@ init_frame_state_for (void)
 gboolean
 mono_arch_has_unwind_info (gconstpointer addr)
 {
-#if 0
-       struct frame_state state_in;
-       struct frame_state *res;
-
-       if (!inited) 
-               init_frame_state_for ();
-       
-       if (!frame_state_for)
-               return FALSE;
-
-       g_assert (method->addr);
-
-       memset (&state_in, 0, sizeof (state_in));
-
-       /* offset 10 is just a guess, but it works for all methods tested */
-       if ((res = frame_state_for ((char *)method->addr + 10, &state_in))) {
-
-               if (res->saved [X86_EBX] != 1 ||
-                   res->saved [X86_EDI] != 1 ||
-                   res->saved [X86_EBP] != 1 ||
-                   res->saved [X86_ESI] != 1) {
-                       return FALSE;
-               }
-               return TRUE;
-       } else {
-               return FALSE;
-       }
-#else
        return FALSE;
-#endif
 }
 
 /*========================= End of Function ========================*/
 
 /*------------------------------------------------------------------*/
 /*                                                                  */
-/* Name                - s390_unwind_native_frame                          */
-/*                                                                  */
-/* Function    - Use the context to unwind a stack frame.          */
-/*                                                                  */
-/*------------------------------------------------------------------*/
-
-static MonoJitInfo *
-s390_unwind_native_frame (MonoDomain *domain, MonoJitTlsData *jit_tls, 
-                         struct sigcontext *ctx, struct sigcontext *new_ctx, 
-                         MonoLMF *lmf, char **trace)
-{
-#if 0
-       struct stack_frame *frame;
-       gpointer max_stack;
-       MonoJitInfo *ji;
-       struct frame_state state_in;
-       struct frame_state *res;
-
-       if (trace)
-               *trace = NULL;
-
-       if (!inited) 
-               init_frame_state_for ();
-
-       if (!frame_state_for)
-               return FALSE;
-
-       frame = MONO_CONTEXT_GET_BP (ctx);
-
-       max_stack = lmf && lmf->method ? lmf : jit_tls->end_of_stack;
-
-       *new_ctx = *ctx;
-
-       memset (&state_in, 0, sizeof (state_in));
-
-       while ((gpointer)frame->next < (gpointer)max_stack) {
-               gpointer ip, addr = frame->return_address;
-               void *cfa;
-               char *tmp, **symbols;
-
-               if (trace) {
-                       ip = MONO_CONTEXT_GET_IP (new_ctx);
-                       symbols = get_backtrace_symbols (&ip, 1);
-                       if (*trace)
-                               tmp = g_strdup_printf ("%s\nin (unmanaged) %s", *trace, symbols [0]);
-                       else
-                               tmp = g_strdup_printf ("in (unmanaged) %s", symbols [0]);
-
-                       free (symbols);
-                       g_free (*trace);
-                       *trace = tmp;
-               }
-
-               if ((res = frame_state_for (addr, &state_in))) {        
-                       int i;
-
-                       cfa = (gint8*) (get_sigcontext_reg (new_ctx, res->cfa_reg) + res->cfa_offset);
-                       frame = (struct stack_frame *)((gint8*)cfa - 8);
-                       for (i = 0; i < DWARF_FRAME_REGISTERS + 1; i++) {
-                               int how = res->saved[i];
-                               long val;
-                               g_assert ((how == 0) || (how == 1));
-                       
-                               if (how == 1) {
-                                       val = * (long*) ((gint8*)cfa + res->reg_or_offset[i]);
-                                       set_sigcontext_reg (new_ctx, i, val);
-                               }
-                       }
-                       new_ctx->SC_ESP = (long)cfa;
-
-                       if (res->saved [X86_EBX] == 1 &&
-                           res->saved [X86_EDI] == 1 &&
-                           res->saved [X86_EBP] == 1 &&
-                           res->saved [X86_ESI] == 1 &&
-                           (ji = mono_jit_info_table_find (domain, frame->return_address))) {
-                               //printf ("FRAME CFA %s\n", mono_method_full_name (ji->method, TRUE));
-                               return ji;
-                       }
-
-               } else {
-//                     printf ("FRAME %p %p %p\n", 
-//                             frame, MONO_CONTEXT_GET_IP (new_ctx), 
-//                             mono_jit_info_table_find (domain, MONO_CONTEXT_GET_IP (new_ctx)));
-
-                       MONO_CONTEXT_SET_IP (new_ctx, frame->return_address);
-                       frame = frame->next;
-                       MONO_CONTEXT_SET_BP (new_ctx, frame);
-
-                       /* stop if !frame or when we detect an unexpected managed frame */
-                       if (!frame || mono_jit_info_table_find (domain, frame->return_address)) {
-                               if (trace) {
-                                       g_free (*trace);
-                                       *trace = NULL;
-                               }
-                               return NULL;
-                       }
-               }
-       }
-
-       if (trace) {
-               g_free (*trace);
-               *trace = NULL;
-       }
-#endif
-       return NULL;
-}
-
-/*========================= End of Function ========================*/
-
-/*------------------------------------------------------------------*/
-/*                                                                  */
-/* Name                - arch_get_call_filter                              */
+/* Name                - mono_arch_get_call_filter                         */
 /*                                                                  */
 /* Function    - Return a pointer to a method which calls an       */
 /*                exception filter. We also use this function to    */
@@ -377,10 +104,10 @@ s390_unwind_native_frame (MonoDomain *domain, MonoJitTlsData *jit_tls,
 /*                                                                  */
 /*------------------------------------------------------------------*/
 
-static gpointer
-arch_get_call_filter (void)
+gpointer
+mono_arch_get_call_filter (void)
 {
-       static guint8 start [256];
+       static guint8 *start;
        static int inited = 0;
        guint8 *code;
        int alloc_size, pos, i;
@@ -390,7 +117,7 @@ arch_get_call_filter (void)
 
        inited = 1;
        /* call_filter (MonoContext *ctx, unsigned long eip, gpointer exc) */
-       code = start;
+       code = start = mono_global_codeman_reserve (512);
 
        s390_stm (code, s390_r6, s390_r14, STK_BASE, S390_REG_SAVE_OFFSET);
        s390_lr  (code, s390_r14, STK_BASE);
@@ -406,46 +133,71 @@ arch_get_call_filter (void)
        /*------------------------------------------------------*/
        /* save floating point registers on stack               */
        /*------------------------------------------------------*/
-       s390_stm (code, s390_r0, s390_r13, STK_BASE, S390_CALLFILTER_INTREGS);
-       pos = S390_CALLFILTER_FLTREGS;
-       for (i = 0; i < 16; ++i) {
-               s390_std (code, i, 0, STK_BASE, pos);
-               pos += sizeof (gdouble);
-       }
+//     pos = S390_CALLFILTER_FLTREGS;
+//     for (i = 0; i < 16; ++i) {
+//             s390_std (code, i, 0, STK_BASE, pos);
+//             pos += sizeof (gdouble);
+//     }
 
        /*------------------------------------------------------*/
        /* save access registers on stack                       */
        /*------------------------------------------------------*/
-       s390_stam (code, s390_r0, s390_r15, STK_BASE, S390_CALLFILTER_ACCREGS);
+//     s390_stam (code, s390_a0, s390_a15, STK_BASE, S390_CALLFILTER_ACCREGS);
 
+       /*------------------------------------------------------*/
+       /* Get A(Context)                                       */
+       /*------------------------------------------------------*/
        s390_lr   (code, s390_r13, s390_r2);
-       s390_lr   (code, s390_r14, s390_r3);
+
+       /*------------------------------------------------------*/
+       /* Get A(Handler Entry Point)                           */
+       /*------------------------------------------------------*/
+       s390_lr   (code, s390_r0, s390_r3);
+
+       /*------------------------------------------------------*/
+       /* Set parameter register with Exception                */
+       /*------------------------------------------------------*/
        s390_lr   (code, s390_r2, s390_r4);
 
-       s390_lm   (code, s390_r0, s390_r1, s390_r13, G_STRUCT_OFFSET(MonoContext, uc_mcontext.gregs));
-       s390_lm   (code, s390_r3, s390_r12, s390_r13, G_STRUCT_OFFSET(MonoContext, uc_mcontext.gregs[2]));
+       /*------------------------------------------------------*/
+       /* Load all registers with values from the context      */
+       /*------------------------------------------------------*/
+       s390_lm   (code, s390_r3, s390_r12, s390_r13, 
+                  G_STRUCT_OFFSET(MonoContext, uc_mcontext.gregs[3]));
        pos = G_STRUCT_OFFSET(MonoContext, uc_mcontext.fpregs.fprs[0]);
        for (i = 0; i < 16; ++i) {
                s390_ld  (code, i, 0, s390_r13, pos);
                pos += sizeof(gdouble);
        }
+       
+       /*------------------------------------------------------*/
+       /* Point at the copied stack frame and call the filter  */
+       /*------------------------------------------------------*/
+       s390_lr   (code, s390_r1, s390_r0);
+       s390_basr (code, s390_r14, s390_r1);
 
-       s390_basr (code, s390_r14, s390_r14);
+       /*------------------------------------------------------*/
+       /* Save return value                                    */
+       /*------------------------------------------------------*/
+       s390_lr   (code, s390_r14, s390_r2);
 
-       /* restore all the regs from the stack */
+       /*------------------------------------------------------*/
+       /* Restore all the regs from the stack                  */
+       /*------------------------------------------------------*/
        s390_lm (code, s390_r0, s390_r13, STK_BASE, S390_CALLFILTER_INTREGS);
-       pos = S390_CALLFILTER_FLTREGS;
-       for (i = 0; i < 16; ++i) {
-               s390_ld (code, i, 0, STK_BASE, pos);
-               pos += sizeof (gdouble);
-       }
-
-       s390_lam  (code, s390_r0, s390_r15, STK_BASE, S390_CALLFILTER_ACCREGS);
+//     pos = S390_CALLFILTER_FLTREGS;
+//     for (i = 0; i < 16; ++i) {
+//             s390_ld (code, i, 0, STK_BASE, pos);
+//             pos += sizeof (gdouble);
+//     }
+
+       s390_lr   (code, s390_r2, s390_r14);
+//     s390_lam  (code, s390_a0, s390_a15, STK_BASE, S390_CALLFILTER_ACCREGS);
        s390_ahi  (code, s390_r15, alloc_size);
        s390_lm   (code, s390_r6, s390_r14, STK_BASE, S390_REG_SAVE_OFFSET);
        s390_br   (code, s390_r14);
 
-       g_assert ((code - start) < sizeof(start));
+       g_assert ((code - start) < SZ_THROW); 
        return start;
 }
 
@@ -453,18 +205,17 @@ arch_get_call_filter (void)
 
 /*------------------------------------------------------------------*/
 /*                                                                  */
-/* Name                - arch_get_restore_context                          */
+/* Name                - throw_exception.                                  */
 /*                                                                  */
-/* Function    - Return a pointer to a method which restores a     */
-/*                previously saved context.                         */
+/* Function    - Raise an exception based on the parameters passed.*/
 /*                                                                  */
 /*------------------------------------------------------------------*/
 
 static void
 throw_exception (MonoObject *exc, unsigned long ip, unsigned long sp, 
-                gulong *int_regs, gdouble *fp_regs, gulong *acc_regs, guint fpc)
+                gulong *int_regs, gdouble *fp_regs, gulong *acc_regs, 
+                guint fpc, gboolean rethrow)
 {
-       static void (*restore_context) (MonoContext *);
        MonoContext ctx;
        int iReg;
        
@@ -486,6 +237,11 @@ throw_exception (MonoObject *exc, unsigned long ip, unsigned long sp,
        MONO_CONTEXT_SET_BP (&ctx, sp);
        MONO_CONTEXT_SET_IP (&ctx, ip);
        
+       if (mono_object_isinst (exc, mono_defaults.exception_class)) {
+               MonoException *mono_ex = (MonoException*)exc;
+               if (!rethrow)
+                       mono_ex->stack_trace = NULL;
+       }
        mono_arch_handle_exception (&ctx, exc, FALSE);
        setcontext(&ctx);
 
@@ -496,7 +252,7 @@ throw_exception (MonoObject *exc, unsigned long ip, unsigned long sp,
 
 /*------------------------------------------------------------------*/
 /*                                                                  */
-/* Name                - arch_get_throw_exception_generic                  */
+/* Name                - get_throw_exception_generic                       */
 /*                                                                  */
 /* Function    - Return a function pointer which can be used to    */
 /*                raise exceptions. The returned function has the   */
@@ -507,7 +263,8 @@ throw_exception (MonoObject *exc, unsigned long ip, unsigned long sp,
 /*------------------------------------------------------------------*/
 
 static gpointer 
-mono_arch_get_throw_exception_generic (guint8 *start, int size, int by_name)
+get_throw_exception_generic (guint8 *start, int size, 
+                            int by_name, gboolean rethrow)
 {
        guint8 *code;
        int alloc_size, pos, i, offset;
@@ -567,6 +324,8 @@ mono_arch_get_throw_exception_generic (guint8 *start, int size, int by_name)
        s390_la   (code, s390_r7, 0, STK_BASE, S390_THROWSTACK_ACCREGS);
        s390_st   (code, s390_r7, 0, STK_BASE, S390_THROWSTACK_ACCPRM);
        s390_stfpc(code, STK_BASE, S390_THROWSTACK_FPCPRM);
+       s390_lhi  (code, s390_r7, rethrow);
+       s390_st   (code, s390_r7, 0, STK_BASE, S390_THROWSTACK_RETHROW);
        offset = (guint32) S390_RELATIVE(throw_exception, code);
        s390_brasl(code, s390_r14, offset);
        /* we should never reach this breakpoint */
@@ -591,12 +350,13 @@ mono_arch_get_throw_exception_generic (guint8 *start, int size, int by_name)
 gpointer 
 mono_arch_get_throw_exception (void)
 {
-       static guint8 start [128];
+       static guint8 *start;
        static int inited = 0;
 
        if (inited)
                return start;
-       mono_arch_get_throw_exception_generic (start, sizeof (start), FALSE);
+       start = mono_global_codeman_reserve (SZ_THROW);
+       get_throw_exception_generic (start, SZ_THROW, FALSE, FALSE);
        inited = 1;
        return start;
 }
@@ -605,56 +365,55 @@ mono_arch_get_throw_exception (void)
 
 /*------------------------------------------------------------------*/
 /*                                                                  */
-/* Name                - arch_get_throw_exception_by_name                  */
+/* Name                - arch_get_rethrow_exception                        */
 /*                                                                  */
 /* Function    - Return a function pointer which can be used to    */
-/*                raise corlib exceptions. The return function has  */
-/*                the following signature:                          */
-/*                void (*func) (char *exc_name);                    */
+/*                raise exceptions. The returned function has the   */
+/*                following signature:                              */
+/*                void (*func) (MonoException *exc);                */
 /*                                                                  */
 /*------------------------------------------------------------------*/
 
 gpointer 
-mono_arch_get_throw_exception_by_name (void)
+mono_arch_get_rethrow_exception (void)
 {
-       static guint8 start [160];
+       static guint8 *start;
        static int inited = 0;
 
        if (inited)
                return start;
-       mono_arch_get_throw_exception_generic (start, sizeof (start), TRUE);
+       start = mono_global_codeman_reserve (SZ_THROW);
+       get_throw_exception_generic (start, SZ_THROW, FALSE, TRUE);
        inited = 1;
        return start;
-}      
+}
 
 /*========================= End of Function ========================*/
 
 /*------------------------------------------------------------------*/
 /*                                                                  */
-/* Name                - glist_to_array                                    */
+/* Name                - arch_get_throw_exception_by_name                  */
 /*                                                                  */
-/* Function    - Convert a list to a mono array.                   */
+/* Function    - Return a function pointer which can be used to    */
+/*                raise corlib exceptions. The return function has  */
+/*                the following signature:                          */
+/*                void (*func) (char *exc_name);                    */
 /*                                                                  */
 /*------------------------------------------------------------------*/
 
-static MonoArray *
-glist_to_array (GList *list) 
+gpointer 
+mono_arch_get_throw_exception_by_name (void)
 {
-       MonoDomain *domain = mono_domain_get ();
-       MonoArray *res;
-       int len, i;
-
-       if (!list)
-               return NULL;
-
-       len = g_list_length (list);
-       res = mono_array_new (domain, mono_defaults.int_class, len);
-
-       for (i = 0; list; list = list->next, i++)
-               mono_array_set (res, gpointer, i, list->data);
+       static guint8 *start;
+       static int inited = 0;
 
-       return res;
-}
+       if (inited)
+               return start;
+       start = mono_global_codeman_reserve (SZ_THROW);
+       get_throw_exception_generic (start, SZ_THROW, TRUE, FALSE);
+       inited = 1;
+       return start;
+}      
 
 /*========================= End of Function ========================*/
 
@@ -677,86 +436,44 @@ glist_to_array (GList *list)
 MonoJitInfo *
 mono_arch_find_jit_info (MonoDomain *domain, MonoJitTlsData *jit_tls, 
                         MonoJitInfo *res, MonoJitInfo *prev_ji, MonoContext *ctx, 
-                        MonoContext *new_ctx, char **trace, MonoLMF **lmf, 
-                        int *native_offset, gboolean *managed)
+                        MonoContext *new_ctx, MonoLMF **lmf, gboolean *managed)
 {
        MonoJitInfo *ji;
        gpointer ip = MONO_CONTEXT_GET_IP (ctx);
-       unsigned long *ptr;
-       char *p;
        MonoS390StackFrame *sframe;
 
        if (prev_ji && 
-           (ip > prev_ji->code_start && 
-           ((guint8 *) ip < ((guint8 *) prev_ji->code_start) + prev_ji->code_size)))
+           (ip >= prev_ji->code_start && 
+           ((guint8 *) ip <= ((guint8 *) prev_ji->code_start) + prev_ji->code_size)))
                ji = prev_ji;
        else
-               ji = mono_jit_info_table_find (domain, ip);
-
-       if (trace)
-               *trace = NULL;
-
-       if (native_offset)
-               *native_offset = -1;
+               ji = mini_jit_info_table_find (domain, ip, NULL);
 
        if (managed)
                *managed = FALSE;
 
        if (ji != NULL) {
-               char *source_location, *tmpaddr, *fname;
-               gint32 address, iloffset;
-               int offset;
+               gint32 address;
 
-//             *new_ctx = *ctx;
-               memcpy(new_ctx, ctx, sizeof(*new_ctx));
+               *new_ctx = *ctx;
 
-               if (*lmf && (MONO_CONTEXT_GET_BP (ctx) >= (gpointer)(*lmf)->ebp)) {
+               if (*lmf && (MONO_CONTEXT_GET_SP (ctx) >= (gpointer)(*lmf)->ebp)) {
                        /* remove any unused lmf */
                        *lmf = (*lmf)->previous_lmf;
                }
 
                address = (char *)ip - (char *)ji->code_start;
 
-               if (native_offset)
-                       *native_offset = address;
-
                if (managed)
                        if (!ji->method->wrapper_type)
                                *managed = TRUE;
 
-               if (trace) {
-                       source_location = mono_debug_source_location_from_address (ji->method, address, NULL, domain);
-                       iloffset = mono_debug_il_offset_from_address (ji->method, address, domain);
-
-                       if (iloffset < 0)
-                               tmpaddr = g_strdup_printf ("<0x%08x>", address);
-                       else
-                               tmpaddr = g_strdup_printf ("[0x%08x]", iloffset);
-               
-                       fname = mono_method_full_name (ji->method, TRUE);
-
-                       if (source_location)
-                               *trace = g_strdup_printf ("in %s (at %s) %s", tmpaddr, source_location, fname);
-                       else
-                               *trace = g_strdup_printf ("in %s %s", tmpaddr, fname);
-
-                       g_free (fname);
-                       g_free (source_location);
-                       g_free (tmpaddr);
-               }
-               sframe = (MonoS390StackFrame *) MONO_CONTEXT_GET_BP (ctx);
-               if (ji->used_regs) {
-               }
+               sframe = (MonoS390StackFrame *) MONO_CONTEXT_GET_SP (ctx);
                MONO_CONTEXT_SET_BP (new_ctx, sframe->prev);
                sframe = (MonoS390StackFrame *) sframe->prev;
                MONO_CONTEXT_SET_IP (new_ctx, sframe->return_address);
-               *res = *ji;
-               return res;
-#ifdef MONO_USE_EXC_TABLES
-       } else if ((ji = s390_unwind_native_frame (domain, jit_tls, ctx, new_ctx, *lmf, trace))) {
-               *res = *ji;
-               return res;
-#endif
+               memcpy (&new_ctx->uc_mcontext.gregs[6], sframe->regs, (8*sizeof(gint32)));
+               return ji;
        } else if (*lmf) {
                
                *new_ctx = *ctx;
@@ -764,28 +481,20 @@ mono_arch_find_jit_info (MonoDomain *domain, MonoJitTlsData *jit_tls,
                if (!(*lmf)->method)
                        return (gpointer)-1;
 
-               if (trace)
-                       *trace = g_strdup_printf ("in (unmanaged) %s", mono_method_full_name ((*lmf)->method, TRUE));
-               
-               if ((ji = mono_jit_info_table_find (domain, (gpointer)(*lmf)->eip))) {
-                       *res = *ji;
+               if ((ji = mini_jit_info_table_find (domain, (gpointer)(*lmf)->eip, NULL))) {
                } else {
-                       memset (res, 0, sizeof (MonoJitInfo));
+                       memset (res, 0, MONO_SIZEOF_JIT_INFO);
                        res->method = (*lmf)->method;
                }
 
-/*
-               MONO_CONTEXT_SET_BP (ctx, (*lmf)->ebp);
-               MONO_CONTEXT_SET_IP (ctx, (*lmf)->eip);
-*/
                memcpy(new_ctx->uc_mcontext.gregs, (*lmf)->gregs, sizeof((*lmf)->gregs));
                memcpy(new_ctx->uc_mcontext.fpregs.fprs, (*lmf)->fregs, sizeof((*lmf)->fregs));
+
                MONO_CONTEXT_SET_BP (new_ctx, (*lmf)->ebp);
                MONO_CONTEXT_SET_IP (new_ctx, (*lmf)->eip);
                *lmf = (*lmf)->previous_lmf;
 
-               return res;
-               
+               return ji ? ji : res;
        }
 
        return NULL;
@@ -795,335 +504,122 @@ mono_arch_find_jit_info (MonoDomain *domain, MonoJitTlsData *jit_tls,
 
 /*------------------------------------------------------------------*/
 /*                                                                  */
-/* Name                - ves_icall_get_trace                               */
+/* Name                - mono_arch_handle_exception                        */
 /*                                                                  */
-/* Function    -                                                   */
+/* Function    - Handle an exception raised by the JIT code.       */
+/*                                                                  */
+/* Parameters   - ctx       - Saved processor state                 */
+/*                obj       - The exception object                  */
+/*                test_only - Only test if the exception is caught, */
+/*                            but don't call handlers               */
 /*                                                                  */
 /*------------------------------------------------------------------*/
 
-MonoArray *
-ves_icall_get_trace (MonoException *exc, gint32 skip, MonoBoolean need_file_info)
+gboolean
+mono_arch_handle_exception (void *uc, gpointer obj, gboolean test_only)
 {
-       MonoDomain *domain = mono_domain_get ();
-       MonoArray *res;
-       MonoArray *ta = exc->trace_ips;
-       int i, len;
-       
-       len = mono_array_length (ta);
-
-       res = mono_array_new (domain, mono_defaults.stack_frame_class, len > skip ? len - skip : 0);
-
-       for (i = skip; i < len; i++) {
-               MonoJitInfo *ji;
-               MonoStackFrame *sf = (MonoStackFrame *)mono_object_new (domain, mono_defaults.stack_frame_class);
-               gpointer ip = mono_array_get (ta, gpointer, i);
-
-               ji = mono_jit_info_table_find (domain, ip);
-               g_assert (ji != NULL);
-
-               sf->method = mono_method_get_object (domain, ji->method, NULL);
-               sf->native_offset = (char *)ip - (char *)ji->code_start;
-
-               sf->il_offset = mono_debug_il_offset_from_address (ji->method, sf->native_offset, domain);
-
-               if (need_file_info) {
-                       gchar *filename;
-                       
-                       filename = mono_debug_source_location_from_address (ji->method, sf->native_offset, &sf->line, domain);
-
-                       sf->filename = filename? mono_string_new (domain, filename): NULL;
-                       sf->column = 0;
-
-                       g_free (filename);
-               }
-
-               mono_array_set (res, gpointer, i, sf);
-       }
-
-       return res;
+       return mono_handle_exception (uc, obj, mono_arch_ip_from_context(uc), test_only);
 }
 
 /*========================= End of Function ========================*/
 
 /*------------------------------------------------------------------*/
 /*                                                                  */
-/* Name                - mono_jit_walk_stack                               */
+/* Name                - mono_arch_ip_from_context                         */
+/*                                                                  */
+/* Function    - Return the instruction pointer from the context.  */
 /*                                                                  */
-/* Function    -                                                   */
+/* Parameters   - sigctx    - Saved processor state                 */
 /*                                                                  */
 /*------------------------------------------------------------------*/
 
-void
-mono_jit_walk_stack (MonoStackWalk func, gpointer user_data) {
-       MonoDomain *domain = mono_domain_get ();
-       MonoJitTlsData *jit_tls = TlsGetValue (mono_jit_tls_id);
-       MonoLMF *lmf = jit_tls->lmf;
-       MonoJitInfo *ji, rji;
-       gint native_offset, il_offset;
-       gboolean managed;
-       MonoContext ctx, new_ctx;
-
-       MONO_CONTEXT_SET_IP (&ctx, __builtin_return_address (0));
-       MONO_CONTEXT_SET_BP (&ctx, __builtin_frame_address (1));
-
-       while (MONO_CONTEXT_GET_BP (&ctx) < jit_tls->end_of_stack) {
-               
-               ji = mono_arch_find_jit_info (domain, jit_tls, &rji, NULL, 
-                                             &ctx, &new_ctx, NULL, &lmf, 
-                                             &native_offset, &managed);
-               g_assert (ji);
-
-               if (ji == (gpointer)-1)
-                       return;
-
-               il_offset = mono_debug_il_offset_from_address (ji->method, native_offset, domain);
-
-               if (func (ji->method, native_offset, il_offset, managed, user_data))
-                       return;
-               
-               ctx = new_ctx;
-       }
+gpointer
+mono_arch_ip_from_context (void *sigctx)
+{
+       return context_get_ip (sigctx);
 }
 
+
 /*========================= End of Function ========================*/
 
 /*------------------------------------------------------------------*/
 /*                                                                  */
-/* Name                - ves_icall_get_frame_info                          */
+/* Name                - mono_arch_get_restore_context                     */
 /*                                                                  */
-/* Function    -                                                   */
+/* Function    - Return the address of the routine that will rest- */
+/*                ore the context.                                  */
 /*                                                                  */
 /*------------------------------------------------------------------*/
 
-MonoBoolean
-ves_icall_get_frame_info (gint32 skip, MonoBoolean need_file_info, 
-                         MonoReflectionMethod **method, 
-                         gint32 *iloffset, gint32 *native_offset,
-                         MonoString **file, gint32 *line, gint32 *column)
+gpointer
+mono_arch_get_restore_context ()
 {
-       MonoDomain *domain = mono_domain_get ();
-       MonoJitTlsData *jit_tls = TlsGetValue (mono_jit_tls_id);
-       MonoLMF *lmf = jit_tls->lmf;
-       MonoJitInfo *ji, rji;
-       MonoContext ctx, new_ctx;
-
-       MONO_CONTEXT_SET_IP (&ctx, ves_icall_get_frame_info);
-       MONO_CONTEXT_SET_BP (&ctx, __builtin_frame_address (0));
-
-       skip++;
-
-       do {
-               ji = mono_arch_find_jit_info (domain, jit_tls, &rji, NULL, 
-                                             &ctx, &new_ctx, NULL, &lmf, 
-                                             native_offset, NULL);
-
-               ctx = new_ctx;
-               
-               if (!ji || ji == (gpointer)-1 || MONO_CONTEXT_GET_BP (&ctx) >= jit_tls->end_of_stack)
-                       return FALSE;
-
-               /* skip all wrappers ??*/
-               if (ji->method->wrapper_type == MONO_WRAPPER_RUNTIME_INVOKE ||
-                   ji->method->wrapper_type == MONO_WRAPPER_REMOTING_INVOKE_WITH_CHECK ||
-                   ji->method->wrapper_type == MONO_WRAPPER_REMOTING_INVOKE)
-                       continue;
-
-               skip--;
-
-       } while (skip >= 0);
-
-       *method = mono_method_get_object (domain, ji->method, NULL);
-       *iloffset = mono_debug_il_offset_from_address (ji->method, *native_offset, domain);
-
-       if (need_file_info) {
-               gchar *filename;
-
-               filename = mono_debug_source_location_from_address (ji->method, *native_offset, line, domain);
-
-               *file = filename? mono_string_new (domain, filename): NULL;
-               *column = 0;
-
-               g_free (filename);
-       }
-
-       return TRUE;
+       return setcontext;
 }
 
+
 /*========================= End of Function ========================*/
 
 /*------------------------------------------------------------------*/
 /*                                                                  */
-/* Name                - mono_arch_handle_exception                        */
-/*                                                                  */
-/* Function    - Handle an exception raised by the JIT code.       */
-/*                                                                  */
-/* Parameters   - ctx       - Saved processor state                 */
-/*                obj       - The exception object                  */
-/*                test_only - Only test if the exception is caught, */
-/*                            but don't call handlers               */
+/* Name                - mono_arch_is_int_overflow                         */
 /*                                                                  */
+/* Function    - Inspect the code that raised the SIGFPE signal    */
+/*               to see if the DivideByZero or Arithmetic exception*/
+/*               should be raised.                                 */
+/*                                                                 */
 /*------------------------------------------------------------------*/
 
 gboolean
-mono_arch_handle_exception (void *uc, gpointer obj, gboolean test_only)
+mono_arch_is_int_overflow (void *uc, void *info)
 {
-       MonoContext     *ctx = uc;
-       MonoDomain      *domain = mono_domain_get ();
-       MonoJitInfo     *ji, rji;
-       static int      (*call_filter) (MonoContext *, gpointer, gpointer) = NULL;
-       MonoJitTlsData  *jit_tls = TlsGetValue (mono_jit_tls_id);
-       MonoLMF         *lmf = jit_tls->lmf;            
-       GList           *trace_ips = NULL;
-       MonoException   *mono_ex;
-
-       g_assert (ctx != NULL);
-       memset(&rji, 0, sizeof(rji));
-       if (!obj) {
-               MonoException *ex = mono_get_exception_null_reference ();
-               ex->message = mono_string_new (domain, 
-                       "Object reference not set to an instance of an object");
-               obj = (MonoObject *)ex;
-       } 
-
-       if (mono_object_isinst (obj, mono_defaults.exception_class)) {
-               mono_ex = (MonoException*)obj;
-               mono_ex->stack_trace = NULL;
-       } else {
-               mono_ex = NULL;
-       }
-
-
-       if (!call_filter)
-               call_filter = arch_get_call_filter ();
-
-       g_assert (jit_tls->end_of_stack);
-       g_assert (jit_tls->abort_func);
-
-       if (!test_only) {
-               MonoContext ctx_cp = *ctx;
-               if (mono_jit_trace_calls != NULL)
-                       g_print ("EXCEPTION handling: %s\n", mono_object_class (obj)->name);
-               if (!mono_arch_handle_exception (&ctx_cp, obj, TRUE)) {
-                       if (mono_break_on_exc)
-                               G_BREAKPOINT ();
-                       mono_unhandled_exception (obj);
-               }
-       }
-
-       while (1) {
-               MonoContext new_ctx;
-               char *trace = NULL;
-               
-               ji = mono_arch_find_jit_info (domain, jit_tls, &rji, &rji, ctx, &new_ctx, 
-                                             test_only ? &trace : NULL, &lmf, NULL, NULL);
-               if (!ji) {
-                       g_warning ("Exception inside function without unwind info");
-                       g_assert_not_reached ();
-               }
-
-               if (ji != (gpointer)-1) {
-                       
-                       if (test_only && ji->method->wrapper_type != MONO_WRAPPER_RUNTIME_INVOKE && mono_ex) {
-                               char *tmp, *strace;
-
-                               trace_ips = g_list_append (trace_ips, MONO_CONTEXT_GET_IP (ctx));
-
-                               if (!mono_ex->stack_trace)
-                                       strace = g_strdup ("");
-                               else
-                                       strace = mono_string_to_utf8 (mono_ex->stack_trace);
-                       
-                               tmp = g_strdup_printf ("%s%s\n", strace, trace);
-                               g_free (strace);
-
-                               mono_ex->stack_trace = mono_string_new (domain, tmp);
-
-                               g_free (tmp);
+       MonoContext *ctx;
+       guint8      *code;
+       guint32     *operand;
+       gboolean    arithExc = TRUE;
+       gint        regNo,
+                   offset;
+
+       ctx  = (MonoContext *) uc;
+       code =  (guint8 *) ((siginfo_t *)info)->si_addr;
+       /*----------------------------------------------------------*/
+       /* Divide operations are the only ones that will give the   */
+       /* divide by zero exception so just check for these ops.    */
+       /*----------------------------------------------------------*/
+       switch (code[0]) {
+               case 0x1d :             /* Divide Register          */
+                       regNo = code[1] & 0x0f; 
+                       if (ctx->uc_mcontext.gregs[regNo] == 0)
+                               arithExc = FALSE;
+               break;
+               case 0x5d :             /* Divide                   */
+                       regNo   = (code[2] & 0xf0 >> 8);        
+                       offset  = *((guint16 *) code+2) & 0x0fff;
+                       operand = (guint32*)(ctx->uc_mcontext.gregs[regNo] + offset);
+                       if (*operand == 0)
+                               arithExc = FALSE; 
+               break;
+               case 0xb9 :             /* Divide logical Register? */
+                       if (code[1] == 0x97) {
+                               regNo = (code[2] & 0xf0 >> 8);  
+                               if (ctx->uc_mcontext.gregs[regNo] == 0)
+                                       arithExc = FALSE;
                        }
-
-                       if (ji->num_clauses) {
-                               int i;
-                               
-                               g_assert (ji->clauses);
-                       
-                               for (i = 0; i < ji->num_clauses; i++) {
-                                       MonoJitExceptionInfo *ei = &ji->clauses [i];
-
-                                       if (ei->try_start <= MONO_CONTEXT_GET_IP (ctx) && 
-                                           MONO_CONTEXT_GET_IP (ctx) <= ei->try_end) { 
-                                               /* catch block */
-                                               if ((ei->flags == MONO_EXCEPTION_CLAUSE_NONE && 
-                                                    mono_object_isinst (obj, mono_class_get (ji->method->klass->image, ei->data.token))) ||
-                                                   ((ei->flags == MONO_EXCEPTION_CLAUSE_FILTER &&
-                                                     call_filter (ctx, ei->data.filter, obj)))) {
-                                                       if (test_only) {
-                                                               if (mono_ex)
-                                                                       mono_ex->trace_ips = glist_to_array (trace_ips);
-                                                               g_list_free (trace_ips);
-                                                               g_free (trace);
-                                                               return TRUE;
-                                                       }
-//                                                     memcpy(ctx, &new_ctx, sizeof(new_ctx));
-                                                       if (mono_jit_trace_calls != NULL)
-                                                               g_print ("EXCEPTION: catch found at clause %d of %s - caught at %p with sp %p\n", 
-                                                                        i, mono_method_full_name (ji->method, TRUE),
-                                                                        ei->handler_start,
-                                                                        MONO_CONTEXT_GET_BP(ctx));
-                                                       MONO_CONTEXT_SET_IP (ctx, ei->handler_start);
-                                                       *((gpointer *)((char *)MONO_CONTEXT_GET_BP (ctx) + ji->exvar_offset)) = obj;
-                                                       jit_tls->lmf = lmf;
-                                                       g_free (trace);
-                                                       return 0;
-                                               }
-                                               if (!test_only && ei->try_start <= MONO_CONTEXT_GET_IP (ctx) && 
-                                                   MONO_CONTEXT_GET_IP (ctx) < ei->try_end &&
-                                                   (ei->flags & MONO_EXCEPTION_CLAUSE_FINALLY)) {
-                                                       if (mono_jit_trace_calls != NULL)
-                                                               g_print ("EXCEPTION: finally clause %d of %s\n", i, mono_method_full_name (ji->method, TRUE));
-                                                       call_filter (ctx, ei->handler_start, NULL);
-                                               }
-                                               
-                                       }
-                               }
-                       }
-               }
-
-               g_free (trace);
-                       
-               *ctx = new_ctx;
-
-               if ((ji == (gpointer)-1) || MONO_CONTEXT_GET_BP (ctx) >= jit_tls->end_of_stack) {
-                       if (!test_only) {
-                               jit_tls->lmf = lmf;
-                               jit_tls->abort_func (obj);
-                               g_assert_not_reached ();
-                       } else {
-                               if (mono_ex)
-                                       mono_ex->trace_ips = glist_to_array (trace_ips);
-                               g_list_free (trace_ips);
-                               return FALSE;
+               break;
+               case 0xe3 :             /* Divide logical?          */
+                       if (code[1] == 0x97) {  
+                               regNo   = (code[2] & 0xf0 >> 8);        
+                               offset  = *((guint32 *) code+1) & 0x000fffff;
+                               operand = (guint32*)(ctx->uc_mcontext.gregs[regNo] + offset);
+                               if (*operand == 0)
+                                       arithExc = FALSE; 
                        }
-               }
+               break;
+               default:
+                       arithExc = TRUE;
        }
-
-       g_assert_not_reached ();
+       ctx->uc_mcontext.psw.addr = (guint32)code;
+       return (arithExc);
 }
 
 /*========================= End of Function ========================*/
-
-/*------------------------------------------------------------------*/
-/*                                                                  */
-/* Name                - mono_arch_ip_from_context                         */
-/*                                                                  */
-/* Function    - Return the instruction pointer from the context.  */
-/*                                                                  */
-/* Parameters   - sigctx    - Saved processor state                 */
-/*                                                                  */
-/*------------------------------------------------------------------*/
-
-gpointer
-mono_arch_ip_from_context (void *sigctx)
-{
-       return context_get_ip (sigctx);
-}
-