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h8300-tdep.c
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/* Target-machine dependent code for Renesas H8/300, for GDB.
Copyright (C) 1988-2015 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 3 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, see <http://www.gnu.org/licenses/>. */
/*
Contributed by Steve Chamberlain
*/
#include "defs.h"
#include "value.h"
#include "arch-utils.h"
#include "regcache.h"
#include "gdbcore.h"
#include "objfiles.h"
#include "dis-asm.h"
#include "dwarf2-frame.h"
#include "frame-base.h"
#include "frame-unwind.h"
enum gdb_regnum
{
E_R0_REGNUM, E_ER0_REGNUM = E_R0_REGNUM, E_ARG0_REGNUM = E_R0_REGNUM,
E_RET0_REGNUM = E_R0_REGNUM,
E_R1_REGNUM, E_ER1_REGNUM = E_R1_REGNUM, E_RET1_REGNUM = E_R1_REGNUM,
E_R2_REGNUM, E_ER2_REGNUM = E_R2_REGNUM, E_ARGLAST_REGNUM = E_R2_REGNUM,
E_R3_REGNUM, E_ER3_REGNUM = E_R3_REGNUM,
E_R4_REGNUM, E_ER4_REGNUM = E_R4_REGNUM,
E_R5_REGNUM, E_ER5_REGNUM = E_R5_REGNUM,
E_R6_REGNUM, E_ER6_REGNUM = E_R6_REGNUM, E_FP_REGNUM = E_R6_REGNUM,
E_SP_REGNUM,
E_CCR_REGNUM,
E_PC_REGNUM,
E_CYCLES_REGNUM,
E_TICK_REGNUM, E_EXR_REGNUM = E_TICK_REGNUM,
E_INST_REGNUM, E_TICKS_REGNUM = E_INST_REGNUM,
E_INSTS_REGNUM,
E_MACH_REGNUM,
E_MACL_REGNUM,
E_SBR_REGNUM,
E_VBR_REGNUM
};
#define H8300_MAX_NUM_REGS 18
#define E_PSEUDO_CCR_REGNUM(gdbarch) (gdbarch_num_regs (gdbarch))
#define E_PSEUDO_EXR_REGNUM(gdbarch) (gdbarch_num_regs (gdbarch)+1)
struct h8300_frame_cache
{
/* Base address. */
CORE_ADDR base;
CORE_ADDR sp_offset;
CORE_ADDR pc;
/* Flag showing that a frame has been created in the prologue code. */
int uses_fp;
/* Saved registers. */
CORE_ADDR saved_regs[H8300_MAX_NUM_REGS];
CORE_ADDR saved_sp;
};
enum
{
h8300_reg_size = 2,
h8300h_reg_size = 4,
h8300_max_reg_size = 4,
};
static int is_h8300hmode (struct gdbarch *gdbarch);
static int is_h8300smode (struct gdbarch *gdbarch);
static int is_h8300sxmode (struct gdbarch *gdbarch);
static int is_h8300_normal_mode (struct gdbarch *gdbarch);
#define BINWORD(gdbarch) ((is_h8300hmode (gdbarch) \
&& !is_h8300_normal_mode (gdbarch)) \
? h8300h_reg_size : h8300_reg_size)
static CORE_ADDR
h8300_unwind_pc (struct gdbarch *gdbarch, struct frame_info *next_frame)
{
return frame_unwind_register_unsigned (next_frame, E_PC_REGNUM);
}
static CORE_ADDR
h8300_unwind_sp (struct gdbarch *gdbarch, struct frame_info *next_frame)
{
return frame_unwind_register_unsigned (next_frame, E_SP_REGNUM);
}
static struct frame_id
h8300_dummy_id (struct gdbarch *gdbarch, struct frame_info *this_frame)
{
CORE_ADDR sp = get_frame_register_unsigned (this_frame, E_SP_REGNUM);
return frame_id_build (sp, get_frame_pc (this_frame));
}
/* Normal frames. */
/* Allocate and initialize a frame cache. */
static void
h8300_init_frame_cache (struct gdbarch *gdbarch,
struct h8300_frame_cache *cache)
{
int i;
/* Base address. */
cache->base = 0;
cache->sp_offset = 0;
cache->pc = 0;
/* Frameless until proven otherwise. */
cache->uses_fp = 0;
/* Saved registers. We initialize these to -1 since zero is a valid
offset (that's where %fp is supposed to be stored). */
for (i = 0; i < gdbarch_num_regs (gdbarch); i++)
cache->saved_regs[i] = -1;
}
#define IS_MOVB_RnRm(x) (((x) & 0xff88) == 0x0c88)
#define IS_MOVW_RnRm(x) (((x) & 0xff88) == 0x0d00)
#define IS_MOVL_RnRm(x) (((x) & 0xff88) == 0x0f80)
#define IS_MOVB_Rn16_SP(x) (((x) & 0xfff0) == 0x6ee0)
#define IS_MOVB_EXT(x) ((x) == 0x7860)
#define IS_MOVB_Rn24_SP(x) (((x) & 0xfff0) == 0x6aa0)
#define IS_MOVW_Rn16_SP(x) (((x) & 0xfff0) == 0x6fe0)
#define IS_MOVW_EXT(x) ((x) == 0x78e0)
#define IS_MOVW_Rn24_SP(x) (((x) & 0xfff0) == 0x6ba0)
/* Same instructions as mov.w, just prefixed with 0x0100. */
#define IS_MOVL_PRE(x) ((x) == 0x0100)
#define IS_MOVL_Rn16_SP(x) (((x) & 0xfff0) == 0x6fe0)
#define IS_MOVL_EXT(x) ((x) == 0x78e0)
#define IS_MOVL_Rn24_SP(x) (((x) & 0xfff0) == 0x6ba0)
#define IS_PUSHFP_MOVESPFP(x) ((x) == 0x6df60d76)
#define IS_PUSH_FP(x) ((x) == 0x01006df6)
#define IS_MOV_SP_FP(x) ((x) == 0x0ff6)
#define IS_SUB2_SP(x) ((x) == 0x1b87)
#define IS_SUB4_SP(x) ((x) == 0x1b97)
#define IS_ADD_IMM_SP(x) ((x) == 0x7a1f)
#define IS_SUB_IMM_SP(x) ((x) == 0x7a3f)
#define IS_SUBL4_SP(x) ((x) == 0x1acf)
#define IS_MOV_IMM_Rn(x) (((x) & 0xfff0) == 0x7905)
#define IS_SUB_RnSP(x) (((x) & 0xff0f) == 0x1907)
#define IS_ADD_RnSP(x) (((x) & 0xff0f) == 0x0907)
#define IS_PUSH(x) (((x) & 0xfff0) == 0x6df0)
/* If the instruction at PC is an argument register spill, return its
length. Otherwise, return zero.
An argument register spill is an instruction that moves an argument
from the register in which it was passed to the stack slot in which
it really lives. It is a byte, word, or longword move from an
argument register to a negative offset from the frame pointer.
CV, 2003-06-16: Or, in optimized code or when the `register' qualifier
is used, it could be a byte, word or long move to registers r3-r5. */
static int
h8300_is_argument_spill (struct gdbarch *gdbarch, CORE_ADDR pc)
{
enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
int w = read_memory_unsigned_integer (pc, 2, byte_order);
if ((IS_MOVB_RnRm (w) || IS_MOVW_RnRm (w) || IS_MOVL_RnRm (w))
&& (w & 0x70) <= 0x20 /* Rs is R0, R1 or R2 */
&& (w & 0x7) >= 0x3 && (w & 0x7) <= 0x5) /* Rd is R3, R4 or R5 */
return 2;
if (IS_MOVB_Rn16_SP (w)
&& 8 <= (w & 0xf) && (w & 0xf) <= 10) /* Rs is R0L, R1L, or R2L */
{
/* ... and d:16 is negative. */
if (read_memory_integer (pc + 2, 2, byte_order) < 0)
return 4;
}
else if (IS_MOVB_EXT (w))
{
if (IS_MOVB_Rn24_SP (read_memory_unsigned_integer (pc + 2,
2, byte_order)))
{
LONGEST disp = read_memory_integer (pc + 4, 4, byte_order);
/* ... and d:24 is negative. */
if (disp < 0 && disp > 0xffffff)
return 8;
}
}
else if (IS_MOVW_Rn16_SP (w)
&& (w & 0xf) <= 2) /* Rs is R0, R1, or R2 */
{
/* ... and d:16 is negative. */
if (read_memory_integer (pc + 2, 2, byte_order) < 0)
return 4;
}
else if (IS_MOVW_EXT (w))
{
if (IS_MOVW_Rn24_SP (read_memory_unsigned_integer (pc + 2,
2, byte_order)))
{
LONGEST disp = read_memory_integer (pc + 4, 4, byte_order);
/* ... and d:24 is negative. */
if (disp < 0 && disp > 0xffffff)
return 8;
}
}
else if (IS_MOVL_PRE (w))
{
int w2 = read_memory_integer (pc + 2, 2, byte_order);
if (IS_MOVL_Rn16_SP (w2)
&& (w2 & 0xf) <= 2) /* Rs is ER0, ER1, or ER2 */
{
/* ... and d:16 is negative. */
if (read_memory_integer (pc + 4, 2, byte_order) < 0)
return 6;
}
else if (IS_MOVL_EXT (w2))
{
int w3 = read_memory_integer (pc + 4, 2, byte_order);
if (IS_MOVL_Rn24_SP (read_memory_integer (pc + 4, 2, byte_order)))
{
LONGEST disp = read_memory_integer (pc + 6, 4, byte_order);
/* ... and d:24 is negative. */
if (disp < 0 && disp > 0xffffff)
return 10;
}
}
}
return 0;
}
/* Do a full analysis of the prologue at PC and update CACHE
accordingly. Bail out early if CURRENT_PC is reached. Return the
address where the analysis stopped.
We handle all cases that can be generated by gcc.
For allocating a stack frame:
mov.w r6,@-sp
mov.w sp,r6
mov.w #-n,rN
add.w rN,sp
mov.w r6,@-sp
mov.w sp,r6
subs #2,sp
(repeat)
mov.l er6,@-sp
mov.l sp,er6
add.l #-n,sp
mov.w r6,@-sp
mov.w sp,r6
subs #4,sp
(repeat)
For saving registers:
mov.w rN,@-sp
mov.l erN,@-sp
stm.l reglist,@-sp
*/
static CORE_ADDR
h8300_analyze_prologue (struct gdbarch *gdbarch,
CORE_ADDR pc, CORE_ADDR current_pc,
struct h8300_frame_cache *cache)
{
enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
unsigned int op;
int regno, i, spill_size;
cache->sp_offset = 0;
if (pc >= current_pc)
return current_pc;
op = read_memory_unsigned_integer (pc, 4, byte_order);
if (IS_PUSHFP_MOVESPFP (op))
{
cache->saved_regs[E_FP_REGNUM] = 0;
cache->uses_fp = 1;
pc += 4;
}
else if (IS_PUSH_FP (op))
{
cache->saved_regs[E_FP_REGNUM] = 0;
pc += 4;
if (pc >= current_pc)
return current_pc;
op = read_memory_unsigned_integer (pc, 2, byte_order);
if (IS_MOV_SP_FP (op))
{
cache->uses_fp = 1;
pc += 2;
}
}
while (pc < current_pc)
{
op = read_memory_unsigned_integer (pc, 2, byte_order);
if (IS_SUB2_SP (op))
{
cache->sp_offset += 2;
pc += 2;
}
else if (IS_SUB4_SP (op))
{
cache->sp_offset += 4;
pc += 2;
}
else if (IS_ADD_IMM_SP (op))
{
cache->sp_offset += -read_memory_integer (pc + 2, 2, byte_order);
pc += 4;
}
else if (IS_SUB_IMM_SP (op))
{
cache->sp_offset += read_memory_integer (pc + 2, 2, byte_order);
pc += 4;
}
else if (IS_SUBL4_SP (op))
{
cache->sp_offset += 4;
pc += 2;
}
else if (IS_MOV_IMM_Rn (op))
{
int offset = read_memory_integer (pc + 2, 2, byte_order);
regno = op & 0x000f;
op = read_memory_unsigned_integer (pc + 4, 2, byte_order);
if (IS_ADD_RnSP (op) && (op & 0x00f0) == regno)
{
cache->sp_offset -= offset;
pc += 6;
}
else if (IS_SUB_RnSP (op) && (op & 0x00f0) == regno)
{
cache->sp_offset += offset;
pc += 6;
}
else
break;
}
else if (IS_PUSH (op))
{
regno = op & 0x000f;
cache->sp_offset += 2;
cache->saved_regs[regno] = cache->sp_offset;
pc += 2;
}
else if (op == 0x0100)
{
op = read_memory_unsigned_integer (pc + 2, 2, byte_order);
if (IS_PUSH (op))
{
regno = op & 0x000f;
cache->sp_offset += 4;
cache->saved_regs[regno] = cache->sp_offset;
pc += 4;
}
else
break;
}
else if ((op & 0xffcf) == 0x0100)
{
int op1;
op1 = read_memory_unsigned_integer (pc + 2, 2, byte_order);
if (IS_PUSH (op1))
{
/* Since the prefix is 0x01x0, this is not a simple pushm but a
stm.l reglist,@-sp */
i = ((op & 0x0030) >> 4) + 1;
regno = op1 & 0x000f;
for (; i > 0; regno++, --i)
{
cache->sp_offset += 4;
cache->saved_regs[regno] = cache->sp_offset;
}
pc += 4;
}
else
break;
}
else
break;
}
/* Check for spilling an argument register to the stack frame.
This could also be an initializing store from non-prologue code,
but I don't think there's any harm in skipping that. */
while ((spill_size = h8300_is_argument_spill (gdbarch, pc)) > 0
&& pc + spill_size <= current_pc)
pc += spill_size;
return pc;
}
static struct h8300_frame_cache *
h8300_frame_cache (struct frame_info *this_frame, void **this_cache)
{
struct gdbarch *gdbarch = get_frame_arch (this_frame);
struct h8300_frame_cache *cache;
int i;
CORE_ADDR current_pc;
if (*this_cache)
return *this_cache;
cache = FRAME_OBSTACK_ZALLOC (struct h8300_frame_cache);
h8300_init_frame_cache (gdbarch, cache);
*this_cache = cache;
/* In principle, for normal frames, %fp holds the frame pointer,
which holds the base address for the current stack frame.
However, for functions that don't need it, the frame pointer is
optional. For these "frameless" functions the frame pointer is
actually the frame pointer of the calling frame. */
cache->base = get_frame_register_unsigned (this_frame, E_FP_REGNUM);
if (cache->base == 0)
return cache;
cache->saved_regs[E_PC_REGNUM] = -BINWORD (gdbarch);
cache->pc = get_frame_func (this_frame);
current_pc = get_frame_pc (this_frame);
if (cache->pc != 0)
h8300_analyze_prologue (gdbarch, cache->pc, current_pc, cache);
if (!cache->uses_fp)
{
/* We didn't find a valid frame, which means that CACHE->base
currently holds the frame pointer for our calling frame. If
we're at the start of a function, or somewhere half-way its
prologue, the function's frame probably hasn't been fully
setup yet. Try to reconstruct the base address for the stack
frame by looking at the stack pointer. For truly "frameless"
functions this might work too. */
cache->base = get_frame_register_unsigned (this_frame, E_SP_REGNUM)
+ cache->sp_offset;
cache->saved_sp = cache->base + BINWORD (gdbarch);
cache->saved_regs[E_PC_REGNUM] = 0;
}
else
{
cache->saved_sp = cache->base + 2 * BINWORD (gdbarch);
cache->saved_regs[E_PC_REGNUM] = -BINWORD (gdbarch);
}
/* Adjust all the saved registers such that they contain addresses
instead of offsets. */
for (i = 0; i < gdbarch_num_regs (gdbarch); i++)
if (cache->saved_regs[i] != -1)
cache->saved_regs[i] = cache->base - cache->saved_regs[i];
return cache;
}
static void
h8300_frame_this_id (struct frame_info *this_frame, void **this_cache,
struct frame_id *this_id)
{
struct h8300_frame_cache *cache =
h8300_frame_cache (this_frame, this_cache);
/* This marks the outermost frame. */
if (cache->base == 0)
return;
*this_id = frame_id_build (cache->saved_sp, cache->pc);
}
static struct value *
h8300_frame_prev_register (struct frame_info *this_frame, void **this_cache,
int regnum)
{
struct gdbarch *gdbarch = get_frame_arch (this_frame);
struct h8300_frame_cache *cache =
h8300_frame_cache (this_frame, this_cache);
gdb_assert (regnum >= 0);
if (regnum == E_SP_REGNUM && cache->saved_sp)
return frame_unwind_got_constant (this_frame, regnum, cache->saved_sp);
if (regnum < gdbarch_num_regs (gdbarch)
&& cache->saved_regs[regnum] != -1)
return frame_unwind_got_memory (this_frame, regnum,
cache->saved_regs[regnum]);
return frame_unwind_got_register (this_frame, regnum, regnum);
}
static const struct frame_unwind h8300_frame_unwind = {
NORMAL_FRAME,
default_frame_unwind_stop_reason,
h8300_frame_this_id,
h8300_frame_prev_register,
NULL,
default_frame_sniffer
};
static CORE_ADDR
h8300_frame_base_address (struct frame_info *this_frame, void **this_cache)
{
struct h8300_frame_cache *cache = h8300_frame_cache (this_frame, this_cache);
return cache->base;
}
static const struct frame_base h8300_frame_base = {
&h8300_frame_unwind,
h8300_frame_base_address,
h8300_frame_base_address,
h8300_frame_base_address
};
static CORE_ADDR
h8300_skip_prologue (struct gdbarch *gdbarch, CORE_ADDR pc)
{
CORE_ADDR func_addr = 0 , func_end = 0;
if (find_pc_partial_function (pc, NULL, &func_addr, &func_end))
{
struct symtab_and_line sal;
struct h8300_frame_cache cache;
/* Found a function. */
sal = find_pc_line (func_addr, 0);
if (sal.end && sal.end < func_end)
/* Found a line number, use it as end of prologue. */
return sal.end;
/* No useable line symbol. Use prologue parsing method. */
h8300_init_frame_cache (gdbarch, &cache);
return h8300_analyze_prologue (gdbarch, func_addr, func_end, &cache);
}
/* No function symbol -- just return the PC. */
return (CORE_ADDR) pc;
}
/* Function: push_dummy_call
Setup the function arguments for calling a function in the inferior.
In this discussion, a `word' is 16 bits on the H8/300s, and 32 bits
on the H8/300H.
There are actually two ABI's here: -mquickcall (the default) and
-mno-quickcall. With -mno-quickcall, all arguments are passed on
the stack after the return address, word-aligned. With
-mquickcall, GCC tries to use r0 -- r2 to pass registers. Since
GCC doesn't indicate in the object file which ABI was used to
compile it, GDB only supports the default --- -mquickcall.
Here are the rules for -mquickcall, in detail:
Each argument, whether scalar or aggregate, is padded to occupy a
whole number of words. Arguments smaller than a word are padded at
the most significant end; those larger than a word are padded at
the least significant end.
The initial arguments are passed in r0 -- r2. Earlier arguments go in
lower-numbered registers. Multi-word arguments are passed in
consecutive registers, with the most significant end in the
lower-numbered register.
If an argument doesn't fit entirely in the remaining registers, it
is passed entirely on the stack. Stack arguments begin just after
the return address. Once an argument has overflowed onto the stack
this way, all subsequent arguments are passed on the stack.
The above rule has odd consequences. For example, on the h8/300s,
if a function takes two longs and an int as arguments:
- the first long will be passed in r0/r1,
- the second long will be passed entirely on the stack, since it
doesn't fit in r2,
- and the int will be passed on the stack, even though it could fit
in r2.
A weird exception: if an argument is larger than a word, but not a
whole number of words in length (before padding), it is passed on
the stack following the rules for stack arguments above, even if
there are sufficient registers available to hold it. Stranger
still, the argument registers are still `used up' --- even though
there's nothing in them.
So, for example, on the h8/300s, if a function expects a three-byte
structure and an int, the structure will go on the stack, and the
int will go in r2, not r0.
If the function returns an aggregate type (struct, union, or class)
by value, the caller must allocate space to hold the return value,
and pass the callee a pointer to this space as an invisible first
argument, in R0.
For varargs functions, the last fixed argument and all the variable
arguments are always passed on the stack. This means that calls to
varargs functions don't work properly unless there is a prototype
in scope.
Basically, this ABI is not good, for the following reasons:
- You can't call vararg functions properly unless a prototype is in scope.
- Structure passing is inconsistent, to no purpose I can see.
- It often wastes argument registers, of which there are only three
to begin with. */
static CORE_ADDR
h8300_push_dummy_call (struct gdbarch *gdbarch, struct value *function,
struct regcache *regcache, CORE_ADDR bp_addr,
int nargs, struct value **args, CORE_ADDR sp,
int struct_return, CORE_ADDR struct_addr)
{
enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
int stack_alloc = 0, stack_offset = 0;
int wordsize = BINWORD (gdbarch);
int reg = E_ARG0_REGNUM;
int argument;
/* First, make sure the stack is properly aligned. */
sp = align_down (sp, wordsize);
/* Now make sure there's space on the stack for the arguments. We
may over-allocate a little here, but that won't hurt anything. */
for (argument = 0; argument < nargs; argument++)
stack_alloc += align_up (TYPE_LENGTH (value_type (args[argument])),
wordsize);
sp -= stack_alloc;
/* Now load as many arguments as possible into registers, and push
the rest onto the stack.
If we're returning a structure by value, then we must pass a
pointer to the buffer for the return value as an invisible first
argument. */
if (struct_return)
regcache_cooked_write_unsigned (regcache, reg++, struct_addr);
for (argument = 0; argument < nargs; argument++)
{
struct cleanup *back_to;
struct type *type = value_type (args[argument]);
int len = TYPE_LENGTH (type);
char *contents = (char *) value_contents (args[argument]);
/* Pad the argument appropriately. */
int padded_len = align_up (len, wordsize);
gdb_byte *padded = xmalloc (padded_len);
back_to = make_cleanup (xfree, padded);
memset (padded, 0, padded_len);
memcpy (len < wordsize ? padded + padded_len - len : padded,
contents, len);
/* Could the argument fit in the remaining registers? */
if (padded_len <= (E_ARGLAST_REGNUM - reg + 1) * wordsize)
{
/* Are we going to pass it on the stack anyway, for no good
reason? */
if (len > wordsize && len % wordsize)
{
/* I feel so unclean. */
write_memory (sp + stack_offset, padded, padded_len);
stack_offset += padded_len;
/* That's right --- even though we passed the argument
on the stack, we consume the registers anyway! Love
me, love my dog. */
reg += padded_len / wordsize;
}
else
{
/* Heavens to Betsy --- it's really going in registers!
Note that on the h8/300s, there are gaps between the
registers in the register file. */
int offset;
for (offset = 0; offset < padded_len; offset += wordsize)
{
ULONGEST word
= extract_unsigned_integer (padded + offset,
wordsize, byte_order);
regcache_cooked_write_unsigned (regcache, reg++, word);
}
}
}
else
{
/* It doesn't fit in registers! Onto the stack it goes. */
write_memory (sp + stack_offset, padded, padded_len);
stack_offset += padded_len;
/* Once one argument has spilled onto the stack, all
subsequent arguments go on the stack. */
reg = E_ARGLAST_REGNUM + 1;
}
do_cleanups (back_to);
}
/* Store return address. */
sp -= wordsize;
write_memory_unsigned_integer (sp, wordsize, byte_order, bp_addr);
/* Update stack pointer. */
regcache_cooked_write_unsigned (regcache, E_SP_REGNUM, sp);
/* Return the new stack pointer minus the return address slot since
that's what DWARF2/GCC uses as the frame's CFA. */
return sp + wordsize;
}
/* Function: extract_return_value
Figure out where in REGBUF the called function has left its return value.
Copy that into VALBUF. Be sure to account for CPU type. */
static void
h8300_extract_return_value (struct type *type, struct regcache *regcache,
void *valbuf)
{
struct gdbarch *gdbarch = get_regcache_arch (regcache);
enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
int len = TYPE_LENGTH (type);
ULONGEST c, addr;
switch (len)
{
case 1:
case 2:
regcache_cooked_read_unsigned (regcache, E_RET0_REGNUM, &c);
store_unsigned_integer (valbuf, len, byte_order, c);
break;
case 4: /* Needs two registers on plain H8/300 */
regcache_cooked_read_unsigned (regcache, E_RET0_REGNUM, &c);
store_unsigned_integer (valbuf, 2, byte_order, c);
regcache_cooked_read_unsigned (regcache, E_RET1_REGNUM, &c);
store_unsigned_integer ((void *)((char *) valbuf + 2), 2, byte_order, c);
break;
case 8: /* long long is now 8 bytes. */
if (TYPE_CODE (type) == TYPE_CODE_INT)
{
regcache_cooked_read_unsigned (regcache, E_RET0_REGNUM, &addr);
c = read_memory_unsigned_integer ((CORE_ADDR) addr, len, byte_order);
store_unsigned_integer (valbuf, len, byte_order, c);
}
else
{
error (_("I don't know how this 8 byte value is returned."));
}
break;
}
}
static void
h8300h_extract_return_value (struct type *type, struct regcache *regcache,
void *valbuf)
{
struct gdbarch *gdbarch = get_regcache_arch (regcache);
enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
ULONGEST c;
switch (TYPE_LENGTH (type))
{
case 1:
case 2:
case 4:
regcache_cooked_read_unsigned (regcache, E_RET0_REGNUM, &c);
store_unsigned_integer (valbuf, TYPE_LENGTH (type), byte_order, c);
break;
case 8: /* long long is now 8 bytes. */
if (TYPE_CODE (type) == TYPE_CODE_INT)
{
regcache_cooked_read_unsigned (regcache, E_RET0_REGNUM, &c);
store_unsigned_integer (valbuf, 4, byte_order, c);
regcache_cooked_read_unsigned (regcache, E_RET1_REGNUM, &c);
store_unsigned_integer ((void *) ((char *) valbuf + 4), 4,
byte_order, c);
}
else
{
error (_("I don't know how this 8 byte value is returned."));
}
break;
}
}
static int
h8300_use_struct_convention (struct type *value_type)
{
/* Types of 1, 2 or 4 bytes are returned in R0/R1, everything else on the
stack. */
if (TYPE_CODE (value_type) == TYPE_CODE_STRUCT
|| TYPE_CODE (value_type) == TYPE_CODE_UNION)
return 1;
return !(TYPE_LENGTH (value_type) == 1
|| TYPE_LENGTH (value_type) == 2
|| TYPE_LENGTH (value_type) == 4);
}
static int
h8300h_use_struct_convention (struct type *value_type)
{
/* Types of 1, 2 or 4 bytes are returned in R0, INT types of 8 bytes are
returned in R0/R1, everything else on the stack. */
if (TYPE_CODE (value_type) == TYPE_CODE_STRUCT
|| TYPE_CODE (value_type) == TYPE_CODE_UNION)
return 1;
return !(TYPE_LENGTH (value_type) == 1
|| TYPE_LENGTH (value_type) == 2
|| TYPE_LENGTH (value_type) == 4
|| (TYPE_LENGTH (value_type) == 8
&& TYPE_CODE (value_type) == TYPE_CODE_INT));
}
/* Function: store_return_value
Place the appropriate value in the appropriate registers.
Primarily used by the RETURN command. */
static void
h8300_store_return_value (struct type *type, struct regcache *regcache,
const void *valbuf)
{
struct gdbarch *gdbarch = get_regcache_arch (regcache);
enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
ULONGEST val;
switch (TYPE_LENGTH (type))
{
case 1:
case 2: /* short... */
val = extract_unsigned_integer (valbuf, TYPE_LENGTH (type), byte_order);
regcache_cooked_write_unsigned (regcache, E_RET0_REGNUM, val);
break;
case 4: /* long, float */
val = extract_unsigned_integer (valbuf, TYPE_LENGTH (type), byte_order);
regcache_cooked_write_unsigned (regcache, E_RET0_REGNUM,
(val >> 16) & 0xffff);
regcache_cooked_write_unsigned (regcache, E_RET1_REGNUM, val & 0xffff);
break;
case 8: /* long long, double and long double
are all defined as 4 byte types so
far so this shouldn't happen. */
error (_("I don't know how to return an 8 byte value."));
break;
}
}
static void
h8300h_store_return_value (struct type *type, struct regcache *regcache,
const void *valbuf)
{
struct gdbarch *gdbarch = get_regcache_arch (regcache);
enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
ULONGEST val;
switch (TYPE_LENGTH (type))
{
case 1:
case 2:
case 4: /* long, float */
val = extract_unsigned_integer (valbuf, TYPE_LENGTH (type), byte_order);
regcache_cooked_write_unsigned (regcache, E_RET0_REGNUM, val);
break;
case 8:
val = extract_unsigned_integer (valbuf, TYPE_LENGTH (type), byte_order);
regcache_cooked_write_unsigned (regcache, E_RET0_REGNUM,
(val >> 32) & 0xffffffff);
regcache_cooked_write_unsigned (regcache, E_RET1_REGNUM,
val & 0xffffffff);
break;
}
}
static enum return_value_convention
h8300_return_value (struct gdbarch *gdbarch, struct value *function,
struct type *type, struct regcache *regcache,
gdb_byte *readbuf, const gdb_byte *writebuf)
{
if (h8300_use_struct_convention (type))
return RETURN_VALUE_STRUCT_CONVENTION;
if (writebuf)
h8300_store_return_value (type, regcache, writebuf);
else if (readbuf)
h8300_extract_return_value (type, regcache, readbuf);
return RETURN_VALUE_REGISTER_CONVENTION;
}
static enum return_value_convention
h8300h_return_value (struct gdbarch *gdbarch, struct value *function,
struct type *type, struct regcache *regcache,
gdb_byte *readbuf, const gdb_byte *writebuf)
{
if (h8300h_use_struct_convention (type))
{
if (readbuf)
{
ULONGEST addr;
regcache_raw_read_unsigned (regcache, E_R0_REGNUM, &addr);
read_memory (addr, readbuf, TYPE_LENGTH (type));
}
return RETURN_VALUE_ABI_RETURNS_ADDRESS;
}
if (writebuf)
h8300h_store_return_value (type, regcache, writebuf);
else if (readbuf)
h8300h_extract_return_value (type, regcache, readbuf);
return RETURN_VALUE_REGISTER_CONVENTION;
}
/* Implementation of 'register_sim_regno' gdbarch method. */
static int
h8300_register_sim_regno (struct gdbarch *gdbarch, int regnum)
{
/* Only makes sense to supply raw registers. */
gdb_assert (regnum >= 0 && regnum < gdbarch_num_regs (gdbarch));
/* We hide the raw ccr from the user by making it nameless. Because
the default register_sim_regno hook returns
LEGACY_SIM_REGNO_IGNORE for unnamed registers, we need to
override it. The sim register numbering is compatible with
gdb's. */
return regnum;
}
static const char *
h8300_register_name (struct gdbarch *gdbarch, int regno)
{
/* The register names change depending on which h8300 processor
type is selected. */
static char *register_names[] = {
"r0", "r1", "r2", "r3", "r4", "r5", "r6",
"sp", "", "pc", "cycles", "tick", "inst",
"ccr", /* pseudo register */
};
if (regno < 0
|| regno >= (sizeof (register_names) / sizeof (*register_names)))
internal_error (__FILE__, __LINE__,
_("h8300_register_name: illegal register number %d"),
regno);
else
return register_names[regno];
}
static const char *
h8300s_register_name (struct gdbarch *gdbarch, int regno)
{
static char *register_names[] = {
"er0", "er1", "er2", "er3", "er4", "er5", "er6",
"sp", "", "pc", "cycles", "", "tick", "inst",
"mach", "macl",
"ccr", "exr" /* pseudo registers */
};
if (regno < 0
|| regno >= (sizeof (register_names) / sizeof (*register_names)))
internal_error (__FILE__, __LINE__,
_("h8300s_register_name: illegal register number %d"),
regno);
else
return register_names[regno];
}
static const char *
h8300sx_register_name (struct gdbarch *gdbarch, int regno)
{
static char *register_names[] = {
"er0", "er1", "er2", "er3", "er4", "er5", "er6",
"sp", "", "pc", "cycles", "", "tick", "inst",
"mach", "macl", "sbr", "vbr",
"ccr", "exr" /* pseudo registers */
};