2004-02-17 Ulrich Weigand <Ulrich.Weigand@de.ibm.com>

	Committed by Jim Blandy  <jimb@redhat.com>.

	* s390-nat.c (SUBOFF): New macro.
	(supply_gregset, fill_gregset): Use it to handle debugging
	of 32-bit exectuables running under a 64-bit kernel.
	* s390-tdep.c: Include "solib-svr4.h".
	(s390_svr4_fetch_link_map_offset): New function.
	(s390x_svr_fetch_link_map_offset): Likewise.
	(s390_gdbarch_init): Call set_solib_svr4_fetch_link_map_offsets.
	* Makefile.in (s390-tdep.o): Update dependencies.

4 files changed, 99 insertions, 3 deletions

diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index d4e53c1..aef385d 100644
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -2,6 +2,15 @@
 
 	Committed by Jim Blandy  <jimb@redhat.com>.
 
+	* s390-nat.c (SUBOFF): New macro.
+	(supply_gregset, fill_gregset): Use it to handle debugging
+	of 32-bit exectuables running under a 64-bit kernel.
+	* s390-tdep.c: Include "solib-svr4.h".
+	(s390_svr4_fetch_link_map_offset): New function.
+	(s390x_svr_fetch_link_map_offset): Likewise.
+	(s390_gdbarch_init): Call set_solib_svr4_fetch_link_map_offsets.
+	* Makefile.in (s390-tdep.o): Update dependencies.
+
 	* s390-tdep.c: Include "trad-frame.h", "frame-base.h", and
 	"frame-unwind.h".
 	(s390_readinstruction): Reformat.  Use read_memory_nobpt.
diff --git a/gdb/Makefile.in b/gdb/Makefile.in
index b26c3f3..3f0d3b8 100644
--- a/gdb/Makefile.in
+++ b/gdb/Makefile.in
@@ -2183,7 +2183,7 @@ s390-tdep.o: s390-tdep.c $(defs_h) $(arch_utils_h) $(frame_h) $(inferior_h) \
 	$(objfiles_h) $(tm_h) $(__bfd_bfd_h) $(floatformat_h) $(regcache_h) \
 	$(trad_frame_h) $(frame_base_h) $(frame_unwind_h) \
 	$(reggroups_h) $(regset_h) $(value_h) $(gdb_assert_h) $(dis_asm_h) \
-	$(s390_tdep_h)
+	$(solib_svr4_h) $(s390_tdep_h)
 scm-exp.o: scm-exp.c $(defs_h) $(symtab_h) $(gdbtypes_h) $(expression_h) \
 	$(parser_defs_h) $(language_h) $(value_h) $(c_lang_h) $(scm_lang_h) \
 	$(scm_tags_h)
diff --git a/gdb/s390-nat.c b/gdb/s390-nat.c
index a2a7759..b8da548 100644
--- a/gdb/s390-nat.c
+++ b/gdb/s390-nat.c
@@ -47,6 +47,18 @@
 
 #define regmap_fpregset s390_regmap_fpregset
 
+/* When debugging a 32-bit executable running under a 64-bit kernel,
+   we have to fix up the 64-bit registers we get from the kernel
+   to make them look like 32-bit registers.  */
+#ifdef __s390x__
+#define SUBOFF(i) \
+	((TARGET_PTR_BIT == 32 \
+	  && ((i) == S390_PSWA_REGNUM \
+	      || ((i) >= S390_R0_REGNUM && (i) <= S390_R15_REGNUM)))? 4 : 0)
+#else
+#define SUBOFF(i) 0
+#endif
+
 
 /* Fill GDB's register array with the general-purpose register values
    in *REGP.  */
@@ -57,7 +69,7 @@ supply_gregset (gregset_t *regp)
   for (i = 0; i < S390_NUM_REGS; i++)
     if (regmap_gregset[i] != -1)
       regcache_raw_supply (current_regcache, i, 
-			   (char *)regp + regmap_gregset[i]);
+			   (char *)regp + regmap_gregset[i] + SUBOFF (i));
 }
 
 /* Fill register REGNO (if it is a general-purpose register) in
@@ -71,7 +83,7 @@ fill_gregset (gregset_t *regp, int regno)
     if (regmap_gregset[i] != -1)
       if (regno == -1 || regno == i)
 	regcache_raw_collect (current_regcache, i, 
-			      (char *)regp + regmap_gregset[i]);
+			      (char *)regp + regmap_gregset[i] + SUBOFF (i));
 }
 
 /* Fill GDB's register array with the floating-point register values
diff --git a/gdb/s390-tdep.c b/gdb/s390-tdep.c
index 227213f..2499c3c 100644
--- a/gdb/s390-tdep.c
+++ b/gdb/s390-tdep.c
@@ -43,6 +43,7 @@
 #include "value.h"
 #include "gdb_assert.h"
 #include "dis-asm.h"
+#include "solib-svr4.h"         /* For struct link_map_offsets.  */
 
 #include "s390-tdep.h"
 
@@ -2848,6 +2849,75 @@ s390_address_class_name_to_type_flags (struct gdbarch *gdbarch, const char *name
 }
 
 
+/* Link map offsets.  */
+
+static struct link_map_offsets *
+s390_svr4_fetch_link_map_offsets (void)
+{
+  static struct link_map_offsets lmo;
+  static struct link_map_offsets *lmp = NULL;
+
+  if (lmp == NULL)
+    {
+      lmp = &lmo;
+
+      lmo.r_debug_size = 8;
+
+      lmo.r_map_offset = 4;
+      lmo.r_map_size   = 4;
+
+      lmo.link_map_size = 20;
+
+      lmo.l_addr_offset = 0;
+      lmo.l_addr_size   = 4;
+
+      lmo.l_name_offset = 4;
+      lmo.l_name_size   = 4;
+
+      lmo.l_next_offset = 12;
+      lmo.l_next_size   = 4;
+
+      lmo.l_prev_offset = 16;
+      lmo.l_prev_size   = 4;
+    }
+
+  return lmp;
+}
+
+static struct link_map_offsets *
+s390x_svr4_fetch_link_map_offsets (void)
+{
+  static struct link_map_offsets lmo;
+  static struct link_map_offsets *lmp = NULL;
+
+  if (lmp == NULL)
+    {
+      lmp = &lmo;
+
+      lmo.r_debug_size = 16;   /* All we need.  */
+
+      lmo.r_map_offset = 8;
+      lmo.r_map_size   = 8;
+
+      lmo.link_map_size = 40;   /* All we need.  */
+
+      lmo.l_addr_offset = 0;
+      lmo.l_addr_size   = 8;
+
+      lmo.l_name_offset = 8;
+      lmo.l_name_size   = 8;
+
+      lmo.l_next_offset = 24;
+      lmo.l_next_size   = 8;
+
+      lmo.l_prev_offset = 32;
+      lmo.l_prev_size   = 8;
+    }
+
+  return lmp;
+}
+
+
 /* Set up gdbarch struct.  */
 
 static struct gdbarch *
@@ -2927,6 +2997,9 @@ s390_gdbarch_init (struct gdbarch_info info, struct gdbarch_list *arches)
       set_gdbarch_addr_bits_remove (gdbarch, s390_addr_bits_remove);
       set_gdbarch_pseudo_register_read (gdbarch, s390_pseudo_register_read);
       set_gdbarch_pseudo_register_write (gdbarch, s390_pseudo_register_write);
+      set_solib_svr4_fetch_link_map_offsets (gdbarch,
+					     s390_svr4_fetch_link_map_offsets);
+
       break;
     case bfd_mach_s390_64:
       tdep->abi = ABI_LINUX_ZSERIES;
@@ -2941,6 +3014,8 @@ s390_gdbarch_init (struct gdbarch_info info, struct gdbarch_list *arches)
       set_gdbarch_ptr_bit (gdbarch, 64);
       set_gdbarch_pseudo_register_read (gdbarch, s390x_pseudo_register_read);
       set_gdbarch_pseudo_register_write (gdbarch, s390x_pseudo_register_write);
+      set_solib_svr4_fetch_link_map_offsets (gdbarch,
+					     s390x_svr4_fetch_link_map_offsets);
       set_gdbarch_address_class_type_flags (gdbarch,
                                             s390_address_class_type_flags);
       set_gdbarch_address_class_type_flags_to_name (gdbarch,