-#include <stdio.h>
+/* Target-machine dependent code for Hitachi H8/300, for GDB.
+ Copyright (C) 1988, 1990, 1991 Free Software Foundation, Inc.
+
+This file is part of GDB.
+
+This program is free software; you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation; either version 2 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program; if not, write to the Free Software
+Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */
+
+/*
+ Contributed by Steve Chamberlain
+ sac@cygnus.com
+ */
+
#include "defs.h"
+#include "frame.h"
+#include "obstack.h"
+#include "symtab.h"
+#include <dis-asm.h>
+#undef NUM_REGS
+#define NUM_REGS 11
+
+#define UNSIGNED_SHORT(X) ((X) & 0xffff)
/* an easy to debug H8 stack frame looks like:
-0x6df2 push r2
-0x6df3 push r3
-0x6df6 push r6
-0x mov.w r7,r6
- subs stuff,sp mov.w #x,r5
- subs r5,sp
+0x6df6 push r6
+0x0d76 mov.w r7,r6
+0x6dfn push reg
+0x7905 nnnn mov.w #n,r5 or 0x1b87 subs #2,sp
+0x1957 sub.w r5,sp
*/
+
#define IS_PUSH(x) ((x & 0xff00)==0x6d00)
-CORE_ADDR h8300_skip_prologue(start_pc)
-CORE_ADDR start_pc;
+#define IS_PUSH_FP(x) (x == 0x6df6)
+#define IS_MOVE_FP(x) (x == 0x0d76)
+#define IS_MOV_SP_FP(x) (x == 0x0d76)
+#define IS_SUB2_SP(x) (x==0x1b87)
+#define IS_MOVK_R5(x) (x==0x7905)
+#define IS_SUB_R5SP(x) (x==0x1957)
+CORE_ADDR examine_prologue ();
+
+void frame_find_saved_regs ();
+CORE_ADDR
+h8300_skip_prologue (start_pc)
+ CORE_ADDR start_pc;
{
- /* Skip past all push insns */
short int w;
-
- w = read_memory_integer(start_pc, 2);
- while (IS_PUSH(w))
- {
- start_pc+=2;
- w = read_memory_integer(start_pc, 2);
- }
-return start_pc;
-
+
+ w = read_memory_unsigned_integer (start_pc, 2);
+ /* Skip past all push insns */
+ while (IS_PUSH_FP (w))
+ {
+ start_pc += 2;
+ w = read_memory_unsigned_integer (start_pc, 2);
+ }
+
+ /* Skip past a move to FP */
+ if (IS_MOVE_FP (w))
+ {
+ start_pc += 2;
+ w = read_memory_unsigned_integer (start_pc, 2);
+ }
+
+ /* Skip the stack adjust */
+
+ if (IS_MOVK_R5 (w))
+ {
+ start_pc += 2;
+ w = read_memory_unsigned_integer (start_pc, 2);
+ }
+ if (IS_SUB_R5SP (w))
+ {
+ start_pc += 2;
+ w = read_memory_unsigned_integer (start_pc, 2);
+ }
+ while (IS_SUB2_SP (w))
+ {
+ start_pc += 2;
+ w = read_memory_unsigned_integer (start_pc, 2);
+ }
+
+ return start_pc;
+
}
-h8300_pop_frame()
+int
+print_insn (memaddr, stream)
+ CORE_ADDR memaddr;
+ FILE *stream;
{
- printf("pop frame\n");
-
+ disassemble_info info;
+ GDB_INIT_DISASSEMBLE_INFO(info, stream);
+ return print_insn_h8300 (memaddr, &info);
}
-int
-print_insn(memaddr, stream)
-CORE_ADDR memaddr;
-FILE *stream;
-{
- /* Nothing is bigger than 8 bytes */
- char data[8];
- read_memory (memaddr, data, sizeof(data));
- return print_insn_h8300(memaddr, data , stream);
-
-
-}
-
-
-
- FRAME_CHAIN()
- {
-
- printf("Frame chain\n");
-
- }
-
-
+/* Given a GDB frame, determine the address of the calling function's frame.
+ This will be used to create a new GDB frame struct, and then
+ INIT_EXTRA_FRAME_INFO and INIT_FRAME_PC will be called for the new frame.
+
+ For us, the frame address is its stack pointer value, so we look up
+ the function prologue to determine the caller's sp value, and return it. */
+
+FRAME_ADDR
+FRAME_CHAIN (thisframe)
+ FRAME thisframe;
+{
+
+ frame_find_saved_regs (thisframe, (struct frame_saved_regs *) 0);
+ return thisframe->fsr->regs[SP_REGNUM];
+}
+
+/* Put here the code to store, into a struct frame_saved_regs,
+ the addresses of the saved registers of frame described by FRAME_INFO.
+ This includes special registers such as pc and fp saved in special
+ ways in the stack frame. sp is even more special:
+ the address we return for it IS the sp for the next frame.
+
+ We cache the result of doing this in the frame_cache_obstack, since
+ it is fairly expensive. */
+
+void
+frame_find_saved_regs (fi, fsr)
+ struct frame_info *fi;
+ struct frame_saved_regs *fsr;
+{
+ register CORE_ADDR next_addr;
+ register CORE_ADDR *saved_regs;
+ register int regnum;
+ register struct frame_saved_regs *cache_fsr;
+ extern struct obstack frame_cache_obstack;
+ CORE_ADDR ip;
+ struct symtab_and_line sal;
+ CORE_ADDR limit;
+
+ if (!fi->fsr)
+ {
+ cache_fsr = (struct frame_saved_regs *)
+ obstack_alloc (&frame_cache_obstack,
+ sizeof (struct frame_saved_regs));
+ bzero (cache_fsr, sizeof (struct frame_saved_regs));
+
+ fi->fsr = cache_fsr;
+
+ /* Find the start and end of the function prologue. If the PC
+ is in the function prologue, we only consider the part that
+ has executed already. */
+
+ ip = get_pc_function_start (fi->pc);
+ sal = find_pc_line (ip, 0);
+ limit = (sal.end && sal.end < fi->pc) ? sal.end : fi->pc;
+
+ /* This will fill in fields in *fi as well as in cache_fsr. */
+ examine_prologue (ip, limit, fi->frame, cache_fsr, fi);
+ }
+
+ if (fsr)
+ *fsr = *fi->fsr;
+}
+
+/* Fetch the instruction at ADDR, returning 0 if ADDR is beyond LIM or
+ is not the address of a valid instruction, the address of the next
+ instruction beyond ADDR otherwise. *PWORD1 receives the first word
+ of the instruction.*/
+
+CORE_ADDR
+NEXT_PROLOGUE_INSN (addr, lim, pword1)
+ CORE_ADDR addr;
+ CORE_ADDR lim;
+ short *pword1;
+{
+ if (addr < lim + 8)
+ {
+ read_memory (addr, pword1, sizeof (*pword1));
+ SWAP_TARGET_AND_HOST (pword1, sizeof (short));
+
+ return addr + 2;
+ }
+ return 0;
+}
+
+/* Examine the prologue of a function. `ip' points to the first instruction.
+ `limit' is the limit of the prologue (e.g. the addr of the first
+ linenumber, or perhaps the program counter if we're stepping through).
+ `frame_sp' is the stack pointer value in use in this frame.
+ `fsr' is a pointer to a frame_saved_regs structure into which we put
+ info about the registers saved by this frame.
+ `fi' is a struct frame_info pointer; we fill in various fields in it
+ to reflect the offsets of the arg pointer and the locals pointer. */
+
+static CORE_ADDR
+examine_prologue (ip, limit, after_prolog_fp, fsr, fi)
+ register CORE_ADDR ip;
+ register CORE_ADDR limit;
+ FRAME_ADDR after_prolog_fp;
+ struct frame_saved_regs *fsr;
+ struct frame_info *fi;
+{
+ register CORE_ADDR next_ip;
+ int r;
+ int i;
+ int have_fp = 0;
+
+ register int src;
+ register struct pic_prologue_code *pcode;
+ INSN_WORD insn_word;
+ int size, offset;
+ unsigned int reg_save_depth = 2; /* Number of things pushed onto
+ stack, starts at 2, 'cause the
+ PC is already there */
+
+ unsigned int auto_depth = 0; /* Number of bytes of autos */
+
+ char in_frame[11]; /* One for each reg */
+
+ memset (in_frame, 1, 11);
+ for (r = 0; r < 8; r++)
+ {
+ fsr->regs[r] = 0;
+ }
+ if (after_prolog_fp == 0)
+ {
+ after_prolog_fp = read_register (SP_REGNUM);
+ }
+ if (ip == 0 || ip & ~0xffff)
+ return 0;
+
+ next_ip = NEXT_PROLOGUE_INSN (ip, limit, &insn_word);
+
+ /* Skip over any fp push instructions */
+ fsr->regs[6] = after_prolog_fp;
+ while (next_ip && IS_PUSH_FP (insn_word))
+ {
+ ip = next_ip;
+
+ in_frame[insn_word & 0x7] = reg_save_depth;
+ next_ip = NEXT_PROLOGUE_INSN (ip, limit, &insn_word);
+ reg_save_depth += 2;
+ }
+
+ /* Is this a move into the fp */
+ if (next_ip && IS_MOV_SP_FP (insn_word))
+ {
+ ip = next_ip;
+ next_ip = NEXT_PROLOGUE_INSN (ip, limit, &insn_word);
+ have_fp = 1;
+ }
+
+ /* Skip over any stack adjustment, happens either with a number of
+ sub#2,sp or a mov #x,r5 sub r5,sp */
+
+ if (next_ip && IS_SUB2_SP (insn_word))
+ {
+ while (next_ip && IS_SUB2_SP (insn_word))
+ {
+ auto_depth += 2;
+ ip = next_ip;
+ next_ip = NEXT_PROLOGUE_INSN (ip, limit, &insn_word);
+ }
+ }
+ else
+ {
+ if (next_ip && IS_MOVK_R5 (insn_word))
+ {
+ ip = next_ip;
+ next_ip = NEXT_PROLOGUE_INSN (ip, limit, &insn_word);
+ auto_depth += insn_word;
+
+ next_ip = NEXT_PROLOGUE_INSN (next_ip, limit, &insn_word);
+ auto_depth += insn_word;
+
+ }
+ }
+ /* Work out which regs are stored where */
+ while (next_ip && IS_PUSH (insn_word))
+ {
+ ip = next_ip;
+ next_ip = NEXT_PROLOGUE_INSN (ip, limit, &insn_word);
+ fsr->regs[r] = after_prolog_fp + auto_depth;
+ auto_depth += 2;
+ }
+
+ /* The args are always reffed based from the stack pointer */
+ fi->args_pointer = after_prolog_fp;
+ /* Locals are always reffed based from the fp */
+ fi->locals_pointer = after_prolog_fp;
+ /* The PC is at a known place */
+ fi->from_pc = read_memory_unsigned_integer (after_prolog_fp + 2, BINWORD);
+
+ /* Rememeber any others too */
+ in_frame[PC_REGNUM] = 0;
+
+ if (have_fp)
+ /* We keep the old FP in the SP spot */
+ fsr->regs[SP_REGNUM] = (read_memory_unsigned_integer
+ (fsr->regs[6]), BINWORD);
+ else
+ fsr->regs[SP_REGNUM] = after_prolog_fp + auto_depth;
+
+ return (ip);
+}
+
+void
+init_extra_frame_info (fromleaf, fi)
+ int fromleaf;
+ struct frame_info *fi;
+{
+ fi->fsr = 0; /* Not yet allocated */
+ fi->args_pointer = 0; /* Unknown */
+ fi->locals_pointer = 0; /* Unknown */
+ fi->from_pc = 0;
+
+}
+
+/* Return the saved PC from this frame.
+
+ If the frame has a memory copy of SRP_REGNUM, use that. If not,
+ just use the register SRP_REGNUM itself. */
+
+CORE_ADDR
+frame_saved_pc (frame)
+ FRAME frame;
+
+{
+ return frame->from_pc;
+}
+
+CORE_ADDR
+frame_locals_address (fi)
+ struct frame_info *fi;
+{
+ if (!fi->locals_pointer)
+ {
+ struct frame_saved_regs ignore;
+
+ get_frame_saved_regs (fi, &ignore);
+
+ }
+ return fi->locals_pointer;
+}
+
+/* Return the address of the argument block for the frame
+ described by FI. Returns 0 if the address is unknown. */
+
+CORE_ADDR
+frame_args_address (fi)
+ struct frame_info *fi;
+{
+ if (!fi->args_pointer)
+ {
+ struct frame_saved_regs ignore;
+
+ get_frame_saved_regs (fi, &ignore);
+
+ }
+
+ return fi->args_pointer;
+}
+
+void
+h8300_pop_frame ()
+{
+ unsigned regnum;
+ struct frame_saved_regs fsr;
+ struct frame_info *fi;
+
+ FRAME frame = get_current_frame ();
+
+ fi = get_frame_info (frame);
+ get_frame_saved_regs (fi, &fsr);
+
+ for (regnum = 0; regnum < 8; regnum++)
+ {
+ if (fsr.regs[regnum])
+ {
+ write_register (regnum, read_memory_integer(fsr.regs[regnum]), BINWORD);
+ }
+
+ flush_cached_frames ();
+ set_current_frame (create_new_frame (read_register (FP_REGNUM),
+ read_pc ()));
+
+ }
+
+}
+
+void
+print_register_hook (regno)
+{
+ if (regno == 8)
+ {
+ /* CCR register */
+
+ int C, Z, N, V;
+ unsigned char b[2];
+ unsigned char l;
+
+ read_relative_register_raw_bytes (regno, b);
+ l = b[1];
+ printf ("\t");
+ printf ("I-%d - ", (l & 0x80) != 0);
+ printf ("H-%d - ", (l & 0x20) != 0);
+ N = (l & 0x8) != 0;
+ Z = (l & 0x4) != 0;
+ V = (l & 0x2) != 0;
+ C = (l & 0x1) != 0;
+ printf ("N-%d ", N);
+ printf ("Z-%d ", Z);
+ printf ("V-%d ", V);
+ printf ("C-%d ", C);
+ if ((C | Z) == 0)
+ printf ("u> ");
+ if ((C | Z) == 1)
+ printf ("u<= ");
+ if ((C == 0))
+ printf ("u>= ");
+ if (C == 1)
+ printf ("u< ");
+ if (Z == 0)
+ printf ("!= ");
+ if (Z == 1)
+ printf ("== ");
+ if ((N ^ V) == 0)
+ printf (">= ");
+ if ((N ^ V) == 1)
+ printf ("< ");
+ if ((Z | (N ^ V)) == 0)
+ printf ("> ");
+ if ((Z | (N ^ V)) == 1)
+ printf ("<= ");
+ }
+}