-/* Target-dependent code for Motorola 68HC11
+/* Target-dependent code for Motorola 68HC11 & 68HC12
Copyright (C) 1999, 2000 Free Software Foundation, Inc.
Contributed by Stephane Carrez, stcarrez@worldnet.fr
#define M68HC11_REG_SIZE (2)
+struct insn_sequence;
struct gdbarch_tdep
{
/* from the elf header */
the address where the last value is saved. For 68hc12, the stack
pointer points to the last value pushed. No offset is necessary. */
int stack_correction;
+
+ /* Description of instructions in the prologue. */
+ struct insn_sequence *prologue;
};
#define M6811_TDEP gdbarch_tdep (current_gdbarch)
static CORE_ADDR
m68hc11_frame_args_address (struct frame_info *frame)
{
- return frame->frame;
+ return frame->frame + frame->extra_info->size + STACK_CORRECTION + 2;
}
static CORE_ADDR
flush_cached_frames ();
}
+\f
+/* 68HC11 & 68HC12 prologue analysis.
+
+ */
+#define MAX_CODES 12
+
+/* 68HC11 opcodes. */
+#undef M6811_OP_PAGE2
+#define M6811_OP_PAGE2 (0x18)
+#define M6811_OP_LDX (0xde)
+#define M6811_OP_PSHX (0x3c)
+#define M6811_OP_STS (0x9f)
+#define M6811_OP_TSX (0x30)
+#define M6811_OP_XGDX (0x8f)
+#define M6811_OP_ADDD (0xc3)
+#define M6811_OP_TXS (0x35)
+#define M6811_OP_DES (0x34)
+
+/* 68HC12 opcodes. */
+#define M6812_OP_PAGE2 (0x18)
+#define M6812_OP_MOVW (0x01)
+#define M6812_PB_PSHW (0xae)
+#define M6812_OP_STS (0x7f)
+#define M6812_OP_LEAS (0x1b)
+
+/* Operand extraction. */
+#define OP_DIRECT (0x100) /* 8-byte direct addressing. */
+#define OP_IMM_LOW (0x200) /* Low part of 16-bit constant/address. */
+#define OP_IMM_HIGH (0x300) /* High part of 16-bit constant/address. */
+#define OP_PBYTE (0x400) /* 68HC12 indexed operand. */
+
+/* Identification of the sequence. */
+enum m6811_seq_type
+{
+ P_LAST = 0,
+ P_SAVE_REG, /* Save a register on the stack. */
+ P_SET_FRAME, /* Setup the frame pointer. */
+ P_LOCAL_1, /* Allocate 1 byte for locals. */
+ P_LOCAL_2, /* Allocate 2 bytes for locals. */
+ P_LOCAL_N /* Allocate N bytes for locals. */
+};
+
+struct insn_sequence {
+ enum m6811_seq_type type;
+ unsigned length;
+ unsigned short code[MAX_CODES];
+};
+
+/* Sequence of instructions in the 68HC11 function prologue. */
+static struct insn_sequence m6811_prologue[] = {
+ /* Sequences to save a soft-register. */
+ { P_SAVE_REG, 3, { M6811_OP_LDX, OP_DIRECT,
+ M6811_OP_PSHX } },
+ { P_SAVE_REG, 5, { M6811_OP_PAGE2, M6811_OP_LDX, OP_DIRECT,
+ M6811_OP_PAGE2, M6811_OP_PSHX } },
+
+ /* Sequences to allocate local variables. */
+ { P_LOCAL_N, 7, { M6811_OP_TSX,
+ M6811_OP_XGDX,
+ M6811_OP_ADDD, OP_IMM_HIGH, OP_IMM_LOW,
+ M6811_OP_XGDX,
+ M6811_OP_TXS } },
+ { P_LOCAL_N, 11, { M6811_OP_PAGE2, M6811_OP_TSX,
+ M6811_OP_PAGE2, M6811_OP_XGDX,
+ M6811_OP_ADDD, OP_IMM_HIGH, OP_IMM_LOW,
+ M6811_OP_PAGE2, M6811_OP_XGDX,
+ M6811_OP_PAGE2, M6811_OP_TXS } },
+ { P_LOCAL_1, 1, { M6811_OP_DES } },
+ { P_LOCAL_2, 1, { M6811_OP_PSHX } },
+ { P_LOCAL_2, 2, { M6811_OP_PAGE2, M6811_OP_PSHX } },
+
+ /* Initialize the frame pointer. */
+ { P_SET_FRAME, 2, { M6811_OP_STS, OP_DIRECT } },
+ { P_LAST, 0, { 0 } }
+};
+
+
+/* Sequence of instructions in the 68HC12 function prologue. */
+static struct insn_sequence m6812_prologue[] = {
+ { P_SAVE_REG, 5, { M6812_OP_PAGE2, M6812_OP_MOVW, M6812_PB_PSHW,
+ OP_IMM_HIGH, OP_IMM_LOW } },
+ { P_SET_FRAME, 3, { M6812_OP_STS, OP_IMM_HIGH, OP_IMM_LOW } },
+ { P_LOCAL_N, 2, { M6812_OP_LEAS, OP_PBYTE } },
+ { P_LAST, 0 }
+};
+
+
+/* Analyze the sequence of instructions starting at the given address.
+ Returns a pointer to the sequence when it is recognized and
+ the optional value (constant/address) associated with it.
+ Advance the pc for the next sequence. */
+static struct insn_sequence *
+m68hc11_analyze_instruction (struct insn_sequence *seq, CORE_ADDR *pc,
+ CORE_ADDR *val)
+{
+ unsigned char buffer[MAX_CODES];
+ unsigned bufsize;
+ unsigned j;
+ CORE_ADDR cur_val;
+ short v = 0;
+
+ bufsize = 0;
+ for (; seq->type != P_LAST; seq++)
+ {
+ cur_val = 0;
+ for (j = 0; j < seq->length; j++)
+ {
+ if (bufsize < j + 1)
+ {
+ buffer[bufsize] = read_memory_unsigned_integer (*pc + bufsize,
+ 1);
+ bufsize++;
+ }
+ /* Continue while we match the opcode. */
+ if (seq->code[j] == buffer[j])
+ continue;
+
+ if ((seq->code[j] & 0xf00) == 0)
+ break;
+
+ /* Extract a sequence parameter (address or constant). */
+ switch (seq->code[j])
+ {
+ case OP_DIRECT:
+ cur_val = (CORE_ADDR) buffer[j];
+ break;
+
+ case OP_IMM_HIGH:
+ cur_val = cur_val & 0x0ff;
+ cur_val |= (buffer[j] << 8);
+ break;
+
+ case OP_IMM_LOW:
+ cur_val &= 0x0ff00;
+ cur_val |= buffer[j];
+ break;
+
+ case OP_PBYTE:
+ if ((buffer[j] & 0xE0) == 0x80)
+ {
+ v = buffer[j] & 0x1f;
+ if (v & 0x10)
+ v |= 0xfff0;
+ }
+ else if ((buffer[j] & 0xfe) == 0xf0)
+ {
+ v = read_memory_unsigned_integer (*pc + j + 1, 1);
+ if (buffer[j] & 1)
+ v |= 0xff00;
+ }
+ else if (buffer[j] == 0xf2)
+ {
+ v = read_memory_unsigned_integer (*pc + j + 1, 2);
+ }
+ cur_val = v;
+ break;
+ }
+ }
+
+ /* We have a full match. */
+ if (j == seq->length)
+ {
+ *val = cur_val;
+ *pc = *pc + j;
+ return seq;
+ }
+ }
+ return 0;
+}
+
/* Analyze the function prologue to find some information
about the function:
- the PC of the first line (for m68hc11_skip_prologue)
{
CORE_ADDR save_addr;
CORE_ADDR func_end;
- unsigned char op0, op1, op2;
- int add_sp_mode;
- int sp_adjust = 0;
int size;
int found_frame_point;
int saved_reg;
CORE_ADDR first_pc;
+ int done = 0;
+ struct insn_sequence *seq_table;
first_pc = get_pc_function_start (pc);
size = 0;
return;
}
-#define OP_PAGE2 (0x18)
-#define OP_LDX (0xde)
-#define OP_LDY (0xde)
-#define OP_PSHX (0x3c)
-#define OP_PSHY (0x3c)
-#define OP_STS (0x9f)
-#define OP_TSX (0x30)
-#define OP_TSY (0x30)
-#define OP_XGDX (0x8f)
-#define OP_XGDY (0x8f)
-#define OP_ADDD (0xc3)
-#define OP_TXS (0x35)
-#define OP_TYS (0x35)
-#define OP_DES (0x34)
-
+ seq_table = gdbarch_tdep (current_gdbarch)->prologue;
+
/* The 68hc11 stack is as follows:
*/
pc = first_pc;
func_end = pc + 128;
- add_sp_mode = 0;
found_frame_point = 0;
- while (pc + 2 < func_end)
+ *frame_offset = 0;
+ save_addr = fp;
+ while (!done && pc + 2 < func_end)
{
- op0 = read_memory_unsigned_integer (pc, 1);
- op1 = read_memory_unsigned_integer (pc + 1, 1);
- op2 = read_memory_unsigned_integer (pc + 2, 1);
+ struct insn_sequence *seq;
+ CORE_ADDR val;
- /* ldx *frame */
- if (op0 == OP_LDX && op1 == M68HC11_FP_ADDR)
- {
- pc += 2;
- }
+ seq = m68hc11_analyze_instruction (seq_table, &pc, &val);
+ if (seq == 0)
+ break;
- /* ldy *frame */
- else if (op0 == OP_PAGE2 && op1 == OP_LDY
- && op2 == M68HC11_FP_ADDR)
+ if (seq->type == P_SAVE_REG)
{
- pc += 3;
- }
-
- /* pshx */
- else if (op0 == OP_PSHX)
- {
- pc += 1;
- size += 2;
- }
+ if (found_frame_point)
+ {
+ saved_reg = m68hc11_which_soft_register (val);
+ if (saved_reg < 0)
+ break;
- /* pshy */
- else if (op0 == OP_PAGE2 && op1 == OP_PSHX)
- {
- pc += 2;
- size += 2;
+ save_addr -= 2;
+ if (pushed_regs)
+ pushed_regs[saved_reg] = save_addr;
+ }
+ else
+ {
+ size += 2;
+ }
}
-
- /* sts *frame */
- else if (op0 == OP_STS && op1 == M68HC11_FP_ADDR)
+ else if (seq->type == P_SET_FRAME)
{
found_frame_point = 1;
- pc += 2;
- break;
+ *frame_offset = size;
}
- else if (op0 == OP_TSX && op1 == OP_XGDX)
+ else if (seq->type == P_LOCAL_1)
{
- add_sp_mode = 1;
- pc += 2;
- }
- /* des to allocate 1 byte on the stack */
- else if (op0 == OP_DES)
- {
- pc += 1;
size += 1;
}
- else if (op0 == OP_PAGE2 && op1 == OP_TSY && op2 == OP_PAGE2)
- {
- op0 = read_memory_unsigned_integer (pc + 3, 1);
- if (op0 != OP_XGDY)
- break;
-
- add_sp_mode = 2;
- pc += 4;
- }
- else if (add_sp_mode && op0 == OP_ADDD)
- {
- sp_adjust = read_memory_unsigned_integer (pc + 1, 2);
- if (sp_adjust & 0x8000)
- sp_adjust |= 0xffff0000L;
-
- sp_adjust = -sp_adjust;
- add_sp_mode |= 4;
- pc += 3;
- }
- else if (add_sp_mode == (1 | 4) && op0 == OP_XGDX
- && op1 == OP_TXS)
- {
- size += sp_adjust;
- pc += 2;
- add_sp_mode = 0;
- }
- else if (add_sp_mode == (2 | 4) && op0 == OP_PAGE2
- && op1 == OP_XGDY && op2 == OP_PAGE2)
- {
- op0 = read_memory_unsigned_integer (pc + 3, 1);
- if (op0 != OP_TYS)
- break;
-
- size += sp_adjust;
- pc += 4;
- add_sp_mode = 0;
- }
- else
- {
- break;
- }
- }
-
- if (found_frame_point == 0)
- {
- *frame_offset = 0;
- }
- else
- {
- *frame_offset = size;
- }
-
- /* Now, look forward to see how many registers are pushed on the stack.
- We look only for soft registers so there must be a first LDX *REG
- before a PSHX. */
- saved_reg = -1;
- save_addr = fp;
- while (pc + 2 < func_end)
- {
- op0 = read_memory_unsigned_integer (pc, 1);
- op1 = read_memory_unsigned_integer (pc + 1, 1);
- op2 = read_memory_unsigned_integer (pc + 2, 1);
- if (op0 == OP_LDX)
- {
- saved_reg = m68hc11_which_soft_register (op1);
- if (saved_reg < 0 || saved_reg == SOFT_FP_REGNUM)
- break;
-
- pc += 2;
- }
- else if (op0 == OP_PAGE2 && op1 == OP_LDY)
+ else if (seq->type == P_LOCAL_2)
{
- saved_reg = m68hc11_which_soft_register (op2);
- if (saved_reg < 0 || saved_reg == SOFT_FP_REGNUM)
- break;
-
- pc += 3;
- }
- else if (op0 == OP_PSHX)
- {
- /* If there was no load, this is a push for a function call. */
- if (saved_reg < 0 || saved_reg >= M68HC11_ALL_REGS)
- break;
-
- /* Keep track of the address where that register is saved
- on the stack. */
- save_addr -= 2;
- if (pushed_regs)
- pushed_regs[saved_reg] = save_addr;
-
- pc += 1;
- saved_reg = -1;
- }
- else if (op0 == OP_PAGE2 && op1 == OP_PSHY)
- {
- if (saved_reg < 0 || saved_reg >= M68HC11_ALL_REGS)
- break;
-
- /* Keep track of the address where that register is saved
- on the stack. */
- save_addr -= 2;
- if (pushed_regs)
- pushed_regs[saved_reg] = save_addr;
-
- pc += 2;
- saved_reg = -1;
+ size += 2;
}
- else
+ else if (seq->type == P_LOCAL_N)
{
- break;
+ /* Stack pointer is decremented for the allocation. */
+ if (val & 0x8000)
+ size -= (int) (val) | 0xffff0000;
+ else
+ size -= val;
}
}
*first_line = pc;
fi->saved_regs);
addr = fi->frame + fi->extra_info->size + STACK_CORRECTION;
- fi->saved_regs[SOFT_FP_REGNUM] = addr - 2;
+ if (soft_regs[SOFT_FP_REGNUM].name)
+ fi->saved_regs[SOFT_FP_REGNUM] = addr - 2;
fi->saved_regs[HARD_SP_REGNUM] = addr;
fi->saved_regs[HARD_PC_REGNUM] = fi->saved_regs[HARD_SP_REGNUM];
}
{
case bfd_arch_m68hc11:
tdep->stack_correction = 1;
+ tdep->prologue = m6811_prologue;
break;
case bfd_arch_m68hc12:
tdep->stack_correction = 0;
+ tdep->prologue = m6812_prologue;
break;
default:
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