* mips-nat.c (fetch_core_registers, register_addr): Copy from

coredep.c, but zero out FP_REGNUM & ZERO_REGNUM so that stack
	backtraces from core files work.
	* config/decstation.mh, config/irix3.mh:  Remove coredep.o.
	Functions are now defined in mips-nat.c.

gdb/ChangeLog

@@ -1,5 +1,13 @@
 Mon Oct 19 15:09:57 1992  Stu Grossman  (grossman at cygnus.com)
 
+	* mips-nat.c (fetch_core_registers, register_addr):  Copy from
+	coredep.c, but zero out FP_REGNUM & ZERO_REGNUM so that stack
+	backtraces from core files work.
+	* config/decstation.mh, config/irix3.mh:  Remove coredep.o.
+	Functions are now defined in mips-nat.c.
+
+	* tm-irix3.h:  Put MIPS_EFI_SYMBOL_NAME in here too.
+
 	* remote-hms.c:  Disable all uses of serial_nextbaudrate and
 	serial_default_name().
 

gdb/config/decstation.mh

@@ -2,7 +2,7 @@
 XDEPFILES= 
 XM_FILE= xm-mips.h
 NAT_FILE= nm-mips.h
-NATDEPFILES= infptrace.o inftarg.o coredep.o corelow.o mips-nat.o fork-child.o
+NATDEPFILES= infptrace.o inftarg.o corelow.o mips-nat.o fork-child.o
 
 # We can't use MMALLOC because the DECstation RPC library can't cope
 # with a malloc(0) that returns 0.  Besides, it's useless on a machine

gdb/config/irix3.mh

@@ -2,7 +2,7 @@
 XDEPFILES= 
 XM_FILE= xm-irix3.h
 NAT_FILE= nm-irix3.h
-NATDEPFILES= fork-child.o coredep.o corelow.o infptrace.o inftarg.o mips-nat.o
+NATDEPFILES= fork-child.o corelow.o infptrace.o inftarg.o mips-nat.o
 ALLOCA=alloca.o
 ALLOCA1=alloca.o
 MUNCH_DEFINE=-B

gdb/mips-nat.c

@@ -25,6 +25,17 @@ Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.  */
 #include <sys/ptrace.h>
 #include <setjmp.h>		/* For JB_XXX.  */
 
+#include <sys/types.h>
+#include <sys/param.h>
+#include "gdbcore.h"
+
+/* These are needed on various systems to expand REGISTER_U_ADDR.  */
+#include <sys/dir.h>
+#include <sys/file.h>
+#include <sys/stat.h>
+#include <sys/user.h>
+#include <sys/ptrace.h>
+
 /* Size of elements in jmpbuf */
 
 #define JB_ELEMENT_SIZE 4
@@ -144,3 +155,74 @@ get_longjmp_target(pc)
 
   return 1;
 }
+
+/* Extract the register values out of the core file and store
+   them where `read_register' will find them.
+
+   CORE_REG_SECT points to the register values themselves, read into memory.
+   CORE_REG_SIZE is the size of that area.
+   WHICH says which set of registers we are handling (0 = int, 2 = float
+         on machines where they are discontiguous).
+   REG_ADDR is the offset from u.u_ar0 to the register values relative to
+            core_reg_sect.  This is used with old-fashioned core files to
+	    locate the registers in a large upage-plus-stack ".reg" section.
+	    Original upage address X is at location core_reg_sect+x+reg_addr.
+ */
+
+void
+fetch_core_registers (core_reg_sect, core_reg_size, which, reg_addr)
+     char *core_reg_sect;
+     unsigned core_reg_size;
+     int which;
+     unsigned reg_addr;
+{
+  register int regno;
+  register unsigned int addr;
+  int bad_reg = -1;
+  register reg_ptr = -reg_addr;		/* Original u.u_ar0 is -reg_addr. */
+
+  /* If u.u_ar0 was an absolute address in the core file, relativize it now,
+     so we can use it as an offset into core_reg_sect.  When we're done,
+     "register 0" will be at core_reg_sect+reg_ptr, and we can use
+     register_addr to offset to the other registers.  If this is a modern
+     core file without a upage, reg_ptr will be zero and this is all a big
+     NOP.  */
+  if (reg_ptr > core_reg_size)
+    reg_ptr -= KERNEL_U_ADDR;
+
+  for (regno = 0; regno < NUM_REGS; regno++)
+    {
+      addr = register_addr (regno, reg_ptr);
+      if (addr >= core_reg_size) {
+	if (bad_reg < 0)
+	  bad_reg = regno;
+      } else {
+	supply_register (regno, core_reg_sect + addr);
+      }
+    }
+  if (bad_reg >= 0)
+    {
+      error ("Register %s not found in core file.", reg_names[bad_reg]);
+    }
+  supply_register (ZERO_REGNUM, zerobuf);
+  /* Frame ptr reg must appear to be 0; it is faked by stack handling code. */
+  supply_register (FP_REGNUM, zerobuf);
+}
+
+/* Return the address in the core dump or inferior of register REGNO.
+   BLOCKEND is the address of the end of the user structure.  */
+
+unsigned int
+register_addr (regno, blockend)
+     int regno;
+     int blockend;
+{
+  int addr;
+
+  if (regno < 0 || regno >= NUM_REGS)
+    error ("Invalid register number %d.", regno);
+
+  REGISTER_U_ADDR (addr, blockend, regno);
+
+  return addr;
+}

gdb/tm-irix3.h

@@ -314,3 +314,8 @@ typedef struct mips_extra_func_info {
   struct frame_saved_regs *saved_regs;
 
 #define INIT_EXTRA_FRAME_INFO(fromleaf, fci) init_extra_frame_info(fci)
+
+/* Special symbol found in blocks associated with routines.  We can hang
+   mips_extra_func_info_t's off of this.  */
+
+#define MIPS_EFI_SYMBOL_NAME "__GDB_EFI_INFO__"