summaryrefslogtreecommitdiff
path: root/gdb/m68k-tdep.c
diff options
context:
space:
mode:
Diffstat (limited to 'gdb/m68k-tdep.c')
-rw-r--r--gdb/m68k-tdep.c148
1 files changed, 128 insertions, 20 deletions
diff --git a/gdb/m68k-tdep.c b/gdb/m68k-tdep.c
index 2d0428b0b0c..f3b4e9bafa7 100644
--- a/gdb/m68k-tdep.c
+++ b/gdb/m68k-tdep.c
@@ -18,15 +18,9 @@ along with this program; if not, write to the Free Software
Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */
#include "defs.h"
-#include "ieee-float.h"
#include "frame.h"
#include "symtab.h"
-const struct ext_format ext_format_68881 = {
-/* tot sbyte smask expbyte manbyte */
- 12, 0, 0x80, 0,1, 4,8 /* mc68881 */
-};
-
/* Things needed for making the inferior call functions.
It seems like every m68k based machine has almost identical definitions
@@ -193,6 +187,120 @@ CORE_ADDR ip;
return (ip);
}
+void
+m68k_find_saved_regs (frame_info, saved_regs)
+ struct frame_info *frame_info;
+ struct frame_saved_regs *saved_regs;
+{
+ register int regnum;
+ register int regmask;
+ register CORE_ADDR next_addr;
+ register CORE_ADDR pc;
+
+ /* First possible address for a pc in a call dummy for this frame. */
+ CORE_ADDR possible_call_dummy_start =
+ (frame_info)->frame - CALL_DUMMY_LENGTH - FP_REGNUM*4 - 4
+#if defined (HAVE_68881)
+ - 8*12
+#endif
+ ;
+
+ int nextinsn;
+ memset (saved_regs, 0, sizeof (*saved_regs));
+ if ((frame_info)->pc >= possible_call_dummy_start
+ && (frame_info)->pc <= (frame_info)->frame)
+ {
+
+ /* It is a call dummy. We could just stop now, since we know
+ what the call dummy saves and where. But this code proceeds
+ to parse the "prologue" which is part of the call dummy.
+ This is needlessly complex, confusing, and also is the only
+ reason that the call dummy is customized based on HAVE_68881.
+ FIXME. */
+
+ next_addr = (frame_info)->frame;
+ pc = possible_call_dummy_start;
+ }
+ else
+ {
+ pc = get_pc_function_start ((frame_info)->pc);
+ /* Verify we have a link a6 instruction next;
+ if not we lose. If we win, find the address above the saved
+ regs using the amount of storage from the link instruction. */
+ if (044016 == read_memory_integer (pc, 2))
+ next_addr = (frame_info)->frame + read_memory_integer (pc += 2, 4), pc+=4;
+ else if (047126 == read_memory_integer (pc, 2))
+ next_addr = (frame_info)->frame + read_memory_integer (pc += 2, 2), pc+=2;
+ else goto lose;
+ /* If have an addal #-n, sp next, adjust next_addr. */
+ if ((0177777 & read_memory_integer (pc, 2)) == 0157774)
+ next_addr += read_memory_integer (pc += 2, 4), pc += 4;
+ }
+ regmask = read_memory_integer (pc + 2, 2);
+#if defined (HAVE_68881)
+ /* Here can come an fmovem. Check for it. */
+ nextinsn = 0xffff & read_memory_integer (pc, 2);
+ if (0xf227 == nextinsn
+ && (regmask & 0xff00) == 0xe000)
+ { pc += 4; /* Regmask's low bit is for register fp7, the first pushed */
+ for (regnum = FP0_REGNUM + 7; regnum >= FP0_REGNUM; regnum--, regmask >>= 1)
+ if (regmask & 1)
+ saved_regs->regs[regnum] = (next_addr -= 12);
+ regmask = read_memory_integer (pc + 2, 2); }
+#endif
+ /* next should be a moveml to (sp) or -(sp) or a movl r,-(sp) */
+ if (0044327 == read_memory_integer (pc, 2))
+ { pc += 4; /* Regmask's low bit is for register 0, the first written */
+ for (regnum = 0; regnum < 16; regnum++, regmask >>= 1)
+ if (regmask & 1)
+ saved_regs->regs[regnum] = (next_addr += 4) - 4; }
+ else if (0044347 == read_memory_integer (pc, 2))
+ {
+ pc += 4; /* Regmask's low bit is for register 15, the first pushed */
+ for (regnum = 15; regnum >= 0; regnum--, regmask >>= 1)
+ if (regmask & 1)
+ saved_regs->regs[regnum] = (next_addr -= 4);
+ }
+ else if (0x2f00 == (0xfff0 & read_memory_integer (pc, 2)))
+ {
+ regnum = 0xf & read_memory_integer (pc, 2); pc += 2;
+ saved_regs->regs[regnum] = (next_addr -= 4);
+ /* gcc, at least, may use a pair of movel instructions when saving
+ exactly 2 registers. */
+ if (0x2f00 == (0xfff0 & read_memory_integer (pc, 2)))
+ {
+ regnum = 0xf & read_memory_integer (pc, 2);
+ pc += 2;
+ saved_regs->regs[regnum] = (next_addr -= 4);
+ }
+ }
+#if defined (HAVE_68881)
+ /* fmovemx to index of sp may follow. */
+ regmask = read_memory_integer (pc + 2, 2);
+ nextinsn = 0xffff & read_memory_integer (pc, 2);
+ if (0xf236 == nextinsn
+ && (regmask & 0xff00) == 0xf000)
+ { pc += 10; /* Regmask's low bit is for register fp0, the first written */
+ for (regnum = FP0_REGNUM + 7; regnum >= FP0_REGNUM; regnum--, regmask >>= 1)
+ if (regmask & 1)
+ saved_regs->regs[regnum] = (next_addr += 12) - 12;
+ regmask = read_memory_integer (pc + 2, 2); }
+#endif
+ /* clrw -(sp); movw ccr,-(sp) may follow. */
+ if (0x426742e7 == read_memory_integer (pc, 4))
+ saved_regs->regs[PS_REGNUM] = (next_addr -= 4);
+ lose: ;
+ saved_regs->regs[SP_REGNUM] = (frame_info)->frame + 8;
+ saved_regs->regs[FP_REGNUM] = (frame_info)->frame;
+ saved_regs->regs[PC_REGNUM] = (frame_info)->frame + 4;
+#ifdef SIG_SP_FP_OFFSET
+ /* Adjust saved SP_REGNUM for fake _sigtramp frames. */
+ if (frame_info->signal_handler_caller && frame_info->next)
+ saved_regs->regs[SP_REGNUM] = frame_info->next->frame + SIG_SP_FP_OFFSET;
+#endif
+}
+
+
#ifdef USE_PROC_FS /* Target dependent support for /proc */
#include <sys/procfs.h>
@@ -317,7 +425,7 @@ int regno;
{
from = (char *) &registers[REGISTER_BYTE (regi)];
to = (char *) &(fpregsetp -> f_fpregs[regi-FP0_REGNUM][0]);
- bcopy (from, to, REGISTER_RAW_SIZE (regi));
+ memcpy (to, from, REGISTER_RAW_SIZE (regi));
}
}
if ((regno == -1) || (regno == FPC_REGNUM))
@@ -348,38 +456,38 @@ int
get_longjmp_target(pc)
CORE_ADDR *pc;
{
+ char buf[TARGET_PTR_BIT / TARGET_CHAR_BIT];
CORE_ADDR sp, jb_addr;
sp = read_register(SP_REGNUM);
- if (target_read_memory(sp + SP_ARG0, /* Offset of first arg on stack */
- &jb_addr,
- sizeof(CORE_ADDR)))
+ if (target_read_memory (sp + SP_ARG0, /* Offset of first arg on stack */
+ buf,
+ TARGET_PTR_BIT / TARGET_CHAR_BIT))
return 0;
+ jb_addr = extract_address (buf, TARGET_PTR_BIT / TARGET_CHAR_BIT);
- SWAP_TARGET_AND_HOST(&jb_addr, sizeof(CORE_ADDR));
-
- if (target_read_memory(jb_addr + JB_PC * JB_ELEMENT_SIZE, pc,
- sizeof(CORE_ADDR)))
+ if (target_read_memory (jb_addr + JB_PC * JB_ELEMENT_SIZE, buf,
+ TARGET_PTR_BIT / TARGET_CHAR_BIT))
return 0;
- SWAP_TARGET_AND_HOST(pc, sizeof(CORE_ADDR));
+ *pc = extract_address (buf, TARGET_PTR_BIT / TARGET_CHAR_BIT);
return 1;
}
#endif /* GET_LONGJMP_TARGET */
/* Immediately after a function call, return the saved pc before the frame
- is setup. We check for the common case of being inside of a system call,
- and if so, we know that Sun pushes the call # on the stack prior to doing
- the trap. */
+ is setup. For sun3's, we check for the common case of being inside of a
+ system call, and if so, we know that Sun pushes the call # on the stack
+ prior to doing the trap. */
CORE_ADDR
m68k_saved_pc_after_call(frame)
struct frame_info *frame;
{
-#ifdef sun
+#ifdef GDB_TARGET_IS_SUN3
int op;
op = read_memory_integer (frame->pc, 2);
@@ -388,6 +496,6 @@ m68k_saved_pc_after_call(frame)
if (op == P_TRAP)
return read_memory_integer (read_register (SP_REGNUM) + 4, 4);
else
-#endif /* sun */
+#endif /* GDB_TARGET_IS_SUN3 */
return read_memory_integer (read_register (SP_REGNUM), 4);
}
View Lorry Controller Status