Fetch the registers from struct members in the pcb instead of

punning the pcb to an array of ints and using magic indices to
access values in it.  This should prevent silent breakage from
changes in the pcb.

Supply 0 for unavailable registers instead of punning the tss to
an array of ints and using magic indices to access garbage values
in it.  (The registers are in the pcb; there is nothing interesting
in the tss.  This should change someday.  At least for dumps, all
the registers should be saved, and common_tss is a good place to
put them.)

Removed ancient wrong (disabled) method for reading eip.

3 files changed, 57 insertions, 84 deletions

diff --git a/gnu/usr.bin/binutils/gdb/i386/kvm-fbsd.c b/gnu/usr.bin/binutils/gdb/i386/kvm-fbsd.c
index 27e6f6c..92528f7 100644
--- a/gnu/usr.bin/binutils/gdb/i386/kvm-fbsd.c
+++ b/gnu/usr.bin/binutils/gdb/i386/kvm-fbsd.c
@@ -479,7 +479,6 @@ static int found_pcb;
 static int devmem;
 static int kfd;
 static struct pcb pcb;
-static struct i386tss cts;
 
 /* substitutes for the stuff in libkvm which doesn't work */
 /* most of this was taken from the old kgdb */
@@ -497,6 +496,7 @@ kvm_open (efile, cfile, sfile, perm, errout)
   struct stat stb;
   CORE_ADDR addr;
   int cfd;
+  struct i386tss cts;
 
   if ((cfd = open (cfile, perm, 0)) < 0)
     return (cfd);
@@ -811,9 +811,7 @@ read_pcb (fd, uaddr)
      CORE_ADDR uaddr;
 {
   int i;
-  int *pcb_regs = (int *)&pcb;
-  int *cts_regs = (int *)&cts;
-  int	eip;
+  int noreg;
   CORE_ADDR nuaddr = uaddr;
 
   /* need this for the `proc' command to work */
@@ -831,30 +829,23 @@ read_pcb (fd, uaddr)
    * get the register values out of the sys pcb and
    * store them where `read_register' will find them.
    */
-  for (i = 0; i < 3; ++i)
-    supply_register (i, (char *)&cts_regs[i+10]);    /* eax, ecx, edx */
-
-  /* get registers from the pcb */
-  supply_register (3, (char *)&pcb_regs[5]);	/* ebx */
-  supply_register (4, (char *)&pcb_regs[4]);	/* esp */
-  supply_register (5, (char *)&pcb_regs[3]);	/* ebp */
-  supply_register (6, (char *)&pcb_regs[2]);	/* esi */
-  supply_register (7, (char *)&pcb_regs[1]);	/* edi */
-  supply_register (8, (char *)&pcb_regs[6]);	/* eip */
-
-  supply_register (9, (char *)&cts_regs[9]);	/* eflags */
-  for (i = 10; i < 13; ++i)		/* cs, ss, ds */
-    supply_register (i, (char *)&cts_regs[i+9]);
-  supply_register (13, (char *)&cts_regs[18]);	/* es */
-  for (i = 14; i < 16; ++i)		/* fs, gs */
-    supply_register (i, (char *)&cts_regs[i+8]);
-
-#if 0 /* doesn't work ??? */
-  /* Hmm... */
-  if (target_read_memory (pcb_regs[5+10]+4, &eip, sizeof eip, 0))
-    error ("Cannot read PC.");
-  supply_register (8, (char *)&eip);	/* eip */
-#endif
+  /*
+   * XXX many registers aren't available.
+   * XXX for the non-core case, the registers are stale - they are for
+   *     the last context switch to the debugger.
+   * XXX gcc's register numbers aren't all #defined in tm-i386.h.
+   */
+  noreg = 0;
+  for (i = 0; i < 3; ++i)		/* eax,ecx,edx */
+    supply_register (i, (char *)&noreg);
+  supply_register (3, (char *)&pcb.pcb_ebx);
+  supply_register (SP_REGNUM, (char *)&pcb.pcb_esp);
+  supply_register (FP_REGNUM, (char *)&pcb.pcb_ebp);
+  supply_register (6, (char *)&pcb.pcb_esi);
+  supply_register (7, (char *)&pcb.pcb_edi);
+  supply_register (PC_REGNUM, (char *)&pcb.pcb_eip);
+  for (i = 9; i < 16; ++i)		/* eflags, cs, ss, ds, es, fs, gs */
+    supply_register (i, (char *)&noreg);
 
   /* XXX 80387 registers? */
 }
diff --git a/gnu/usr.bin/binutils/gdb/kvm-fbsd.c b/gnu/usr.bin/binutils/gdb/kvm-fbsd.c
index 27e6f6c..92528f7 100644
--- a/gnu/usr.bin/binutils/gdb/kvm-fbsd.c
+++ b/gnu/usr.bin/binutils/gdb/kvm-fbsd.c
@@ -479,7 +479,6 @@ static int found_pcb;
 static int devmem;
 static int kfd;
 static struct pcb pcb;
-static struct i386tss cts;
 
 /* substitutes for the stuff in libkvm which doesn't work */
 /* most of this was taken from the old kgdb */
@@ -497,6 +496,7 @@ kvm_open (efile, cfile, sfile, perm, errout)
   struct stat stb;
   CORE_ADDR addr;
   int cfd;
+  struct i386tss cts;
 
   if ((cfd = open (cfile, perm, 0)) < 0)
     return (cfd);
@@ -811,9 +811,7 @@ read_pcb (fd, uaddr)
      CORE_ADDR uaddr;
 {
   int i;
-  int *pcb_regs = (int *)&pcb;
-  int *cts_regs = (int *)&cts;
-  int	eip;
+  int noreg;
   CORE_ADDR nuaddr = uaddr;
 
   /* need this for the `proc' command to work */
@@ -831,30 +829,23 @@ read_pcb (fd, uaddr)
    * get the register values out of the sys pcb and
    * store them where `read_register' will find them.
    */
-  for (i = 0; i < 3; ++i)
-    supply_register (i, (char *)&cts_regs[i+10]);    /* eax, ecx, edx */
-
-  /* get registers from the pcb */
-  supply_register (3, (char *)&pcb_regs[5]);	/* ebx */
-  supply_register (4, (char *)&pcb_regs[4]);	/* esp */
-  supply_register (5, (char *)&pcb_regs[3]);	/* ebp */
-  supply_register (6, (char *)&pcb_regs[2]);	/* esi */
-  supply_register (7, (char *)&pcb_regs[1]);	/* edi */
-  supply_register (8, (char *)&pcb_regs[6]);	/* eip */
-
-  supply_register (9, (char *)&cts_regs[9]);	/* eflags */
-  for (i = 10; i < 13; ++i)		/* cs, ss, ds */
-    supply_register (i, (char *)&cts_regs[i+9]);
-  supply_register (13, (char *)&cts_regs[18]);	/* es */
-  for (i = 14; i < 16; ++i)		/* fs, gs */
-    supply_register (i, (char *)&cts_regs[i+8]);
-
-#if 0 /* doesn't work ??? */
-  /* Hmm... */
-  if (target_read_memory (pcb_regs[5+10]+4, &eip, sizeof eip, 0))
-    error ("Cannot read PC.");
-  supply_register (8, (char *)&eip);	/* eip */
-#endif
+  /*
+   * XXX many registers aren't available.
+   * XXX for the non-core case, the registers are stale - they are for
+   *     the last context switch to the debugger.
+   * XXX gcc's register numbers aren't all #defined in tm-i386.h.
+   */
+  noreg = 0;
+  for (i = 0; i < 3; ++i)		/* eax,ecx,edx */
+    supply_register (i, (char *)&noreg);
+  supply_register (3, (char *)&pcb.pcb_ebx);
+  supply_register (SP_REGNUM, (char *)&pcb.pcb_esp);
+  supply_register (FP_REGNUM, (char *)&pcb.pcb_ebp);
+  supply_register (6, (char *)&pcb.pcb_esi);
+  supply_register (7, (char *)&pcb.pcb_edi);
+  supply_register (PC_REGNUM, (char *)&pcb.pcb_eip);
+  for (i = 9; i < 16; ++i)		/* eflags, cs, ss, ds, es, fs, gs */
+    supply_register (i, (char *)&noreg);
 
   /* XXX 80387 registers? */
 }
diff --git a/gnu/usr.bin/gdb/gdb/kvm-fbsd.c b/gnu/usr.bin/gdb/gdb/kvm-fbsd.c
index 27e6f6c..92528f7 100644
--- a/gnu/usr.bin/gdb/gdb/kvm-fbsd.c
+++ b/gnu/usr.bin/gdb/gdb/kvm-fbsd.c
@@ -479,7 +479,6 @@ static int found_pcb;
 static int devmem;
 static int kfd;
 static struct pcb pcb;
-static struct i386tss cts;
 
 /* substitutes for the stuff in libkvm which doesn't work */
 /* most of this was taken from the old kgdb */
@@ -497,6 +496,7 @@ kvm_open (efile, cfile, sfile, perm, errout)
   struct stat stb;
   CORE_ADDR addr;
   int cfd;
+  struct i386tss cts;
 
   if ((cfd = open (cfile, perm, 0)) < 0)
     return (cfd);
@@ -811,9 +811,7 @@ read_pcb (fd, uaddr)
      CORE_ADDR uaddr;
 {
   int i;
-  int *pcb_regs = (int *)&pcb;
-  int *cts_regs = (int *)&cts;
-  int	eip;
+  int noreg;
   CORE_ADDR nuaddr = uaddr;
 
   /* need this for the `proc' command to work */
@@ -831,30 +829,23 @@ read_pcb (fd, uaddr)
    * get the register values out of the sys pcb and
    * store them where `read_register' will find them.
    */
-  for (i = 0; i < 3; ++i)
-    supply_register (i, (char *)&cts_regs[i+10]);    /* eax, ecx, edx */
-
-  /* get registers from the pcb */
-  supply_register (3, (char *)&pcb_regs[5]);	/* ebx */
-  supply_register (4, (char *)&pcb_regs[4]);	/* esp */
-  supply_register (5, (char *)&pcb_regs[3]);	/* ebp */
-  supply_register (6, (char *)&pcb_regs[2]);	/* esi */
-  supply_register (7, (char *)&pcb_regs[1]);	/* edi */
-  supply_register (8, (char *)&pcb_regs[6]);	/* eip */
-
-  supply_register (9, (char *)&cts_regs[9]);	/* eflags */
-  for (i = 10; i < 13; ++i)		/* cs, ss, ds */
-    supply_register (i, (char *)&cts_regs[i+9]);
-  supply_register (13, (char *)&cts_regs[18]);	/* es */
-  for (i = 14; i < 16; ++i)		/* fs, gs */
-    supply_register (i, (char *)&cts_regs[i+8]);
-
-#if 0 /* doesn't work ??? */
-  /* Hmm... */
-  if (target_read_memory (pcb_regs[5+10]+4, &eip, sizeof eip, 0))
-    error ("Cannot read PC.");
-  supply_register (8, (char *)&eip);	/* eip */
-#endif
+  /*
+   * XXX many registers aren't available.
+   * XXX for the non-core case, the registers are stale - they are for
+   *     the last context switch to the debugger.
+   * XXX gcc's register numbers aren't all #defined in tm-i386.h.
+   */
+  noreg = 0;
+  for (i = 0; i < 3; ++i)		/* eax,ecx,edx */
+    supply_register (i, (char *)&noreg);
+  supply_register (3, (char *)&pcb.pcb_ebx);
+  supply_register (SP_REGNUM, (char *)&pcb.pcb_esp);
+  supply_register (FP_REGNUM, (char *)&pcb.pcb_ebp);
+  supply_register (6, (char *)&pcb.pcb_esi);
+  supply_register (7, (char *)&pcb.pcb_edi);
+  supply_register (PC_REGNUM, (char *)&pcb.pcb_eip);
+  for (i = 9; i < 16; ++i)		/* eflags, cs, ss, ds, es, fs, gs */
+    supply_register (i, (char *)&noreg);
 
   /* XXX 80387 registers? */
 }