binutils-gdb/opcodes/h8300-dis.c
Alan Modra 832a580781 Re: H8300 use of uninitialised value
This patch also had some problems.  Calculation of maxlen was wrong,
and the insn arg loop needed rearranging to work with a correct length.

	* disassemble.h (opcodes_assert): Declare.
	(OPCODES_ASSERT): Define.
	* disassemble.c: Don't include assert.h.  Include opintl.h.
	(opcodes_assert): New function.
	* h8300-dis.c (bfd_h8_disassemble_init): Use OPCODES_ASSERT.
	(bfd_h8_disassemble): Reduce size of data array.  Correctly
	calculate maxlen.  Omit insn decoding when insn length exceeds
	maxlen.  Exit from nibble loop when looking for E, before
	accessing next data byte.  Move processing of E outside loop.
	Replace tests of maxlen in loop with assertions.
2020-03-26 20:02:42 +10:30

746 lines
18 KiB
C

/* Disassemble h8300 instructions.
Copyright (C) 1993-2020 Free Software Foundation, Inc.
This file is part of the GNU opcodes library.
This library 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, or (at your option)
any later version.
It 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., 51 Franklin Street - Fifth Floor, Boston,
MA 02110-1301, USA. */
#define DEFINE_TABLE
#include "sysdep.h"
#define h8_opcodes h8ops
#include "opcode/h8300.h"
#include "disassemble.h"
#include "opintl.h"
#include "libiberty.h"
struct h8_instruction
{
unsigned int length;
const struct h8_opcode *opcode;
};
struct h8_instruction *h8_instructions;
/* Run through the opcodes and sort them into order to make them easy
to disassemble. */
static void
bfd_h8_disassemble_init (void)
{
unsigned int i;
unsigned int nopcodes;
const struct h8_opcode *p;
struct h8_instruction *pi;
nopcodes = sizeof (h8_opcodes) / sizeof (struct h8_opcode);
h8_instructions = xmalloc (nopcodes * sizeof (struct h8_instruction));
for (p = h8_opcodes, pi = h8_instructions; p->name; p++, pi++)
{
/* Just make sure there are an even number of nibbles in it, and
that the count is the same as the length. */
for (i = 0; p->data.nib[i] != (op_type) E; i++)
;
OPCODES_ASSERT (!(i & 1));
pi->length = i / 2;
pi->opcode = p;
}
/* Add entry for the NULL vector terminator. */
pi->length = 0;
pi->opcode = p;
}
static void
extract_immediate (FILE *stream,
op_type looking_for,
int thisnib,
unsigned char *data,
int *cst,
int *len,
const struct h8_opcode *q)
{
switch (looking_for & SIZE)
{
case L_2:
*len = 2;
*cst = thisnib & 3;
/* DISP2 special treatment. */
if ((looking_for & MODE) == DISP)
{
if (OP_KIND (q->how) == O_MOVAB
|| OP_KIND (q->how) == O_MOVAW
|| OP_KIND (q->how) == O_MOVAL)
{
/* Handling for mova insn. */
switch (q->args.nib[0] & MODE)
{
case INDEXB:
default:
break;
case INDEXW:
*cst *= 2;
break;
case INDEXL:
*cst *= 4;
break;
}
}
else
{
/* Handling for non-mova insn. */
switch (OP_SIZE (q->how))
{
default: break;
case SW:
*cst *= 2;
break;
case SL:
*cst *= 4;
break;
}
}
}
break;
case L_8:
*len = 8;
*cst = data[0];
break;
case L_16:
case L_16U:
*len = 16;
*cst = (data[0] << 8) + data [1];
#if 0
if ((looking_for & SIZE) == L_16)
*cst = (short) *cst; /* Sign extend. */
#endif
break;
case L_32:
*len = 32;
*cst = (((unsigned) data[0] << 24) + (data[1] << 16)
+ (data[2] << 8) + data[3]);
break;
default:
*len = 0;
*cst = 0;
fprintf (stream, "DISP bad size\n");
break;
}
}
static const char *regnames[] =
{
"r0h", "r1h", "r2h", "r3h", "r4h", "r5h", "r6h", "r7h",
"r0l", "r1l", "r2l", "r3l", "r4l", "r5l", "r6l", "r7l"
};
static const char *wregnames[] =
{
"r0", "r1", "r2", "r3", "r4", "r5", "r6", "r7",
"e0", "e1", "e2", "e3", "e4", "e5", "e6", "e7"
};
static const char *lregnames[] =
{
"er0", "er1", "er2", "er3", "er4", "er5", "er6", "er7",
"er0", "er1", "er2", "er3", "er4", "er5", "er6", "er7"
};
static const char *cregnames[] =
{
"ccr", "exr", "mach", "macl", "", "", "vbr", "sbr"
};
static void
print_one_arg (disassemble_info *info,
bfd_vma addr,
op_type x,
int cst,
int cstlen,
int rdisp_n,
int rn,
const char **pregnames,
int len)
{
void * stream = info->stream;
fprintf_ftype outfn = info->fprintf_func;
if ((x & SIZE) == L_3 || (x & SIZE) == L_3NZ)
outfn (stream, "#0x%x", (unsigned) cst);
else if ((x & MODE) == IMM)
outfn (stream, "#0x%x", (unsigned) cst);
else if ((x & MODE) == DBIT || (x & MODE) == KBIT)
outfn (stream, "#%d", (unsigned) cst);
else if ((x & MODE) == CONST_2)
outfn (stream, "#2");
else if ((x & MODE) == CONST_4)
outfn (stream, "#4");
else if ((x & MODE) == CONST_8)
outfn (stream, "#8");
else if ((x & MODE) == CONST_16)
outfn (stream, "#16");
else if ((x & MODE) == REG)
{
switch (x & SIZE)
{
case L_8:
outfn (stream, "%s", regnames[rn]);
break;
case L_16:
case L_16U:
outfn (stream, "%s", wregnames[rn]);
break;
case L_P:
case L_32:
outfn (stream, "%s", lregnames[rn]);
break;
}
}
else if ((x & MODE) == LOWREG)
{
switch (x & SIZE)
{
case L_8:
/* Always take low half of reg. */
outfn (stream, "%s.b", regnames[rn < 8 ? rn + 8 : rn]);
break;
case L_16:
case L_16U:
/* Always take low half of reg. */
outfn (stream, "%s.w", wregnames[rn < 8 ? rn : rn - 8]);
break;
case L_P:
case L_32:
outfn (stream, "%s.l", lregnames[rn]);
break;
}
}
else if ((x & MODE) == POSTINC)
outfn (stream, "@%s+", pregnames[rn]);
else if ((x & MODE) == POSTDEC)
outfn (stream, "@%s-", pregnames[rn]);
else if ((x & MODE) == PREINC)
outfn (stream, "@+%s", pregnames[rn]);
else if ((x & MODE) == PREDEC)
outfn (stream, "@-%s", pregnames[rn]);
else if ((x & MODE) == IND)
outfn (stream, "@%s", pregnames[rn]);
else if ((x & MODE) == ABS || (x & ABSJMP))
outfn (stream, "@0x%x:%d", (unsigned) cst, cstlen);
else if ((x & MODE) == MEMIND)
outfn (stream, "@@%d (0x%x)", cst, cst);
else if ((x & MODE) == VECIND)
{
/* FIXME Multiplier should be 2 or 4, depending on processor mode,
by which is meant "normal" vs. "middle", "advanced", "maximum". */
int offset = (cst + 0x80) * 4;
outfn (stream, "@@%d (0x%x)", offset, offset);
}
else if ((x & MODE) == PCREL)
{
if ((x & SIZE) == L_16 ||
(x & SIZE) == L_16U)
{
outfn (stream, ".%s%d (0x%lx)",
(short) cst > 0 ? "+" : "",
(short) cst,
(long)(addr + (short) cst + len));
}
else
{
outfn (stream, ".%s%d (0x%lx)",
(char) cst > 0 ? "+" : "",
(char) cst,
(long)(addr + (char) cst + len));
}
}
else if ((x & MODE) == DISP)
outfn (stream, "@(0x%x:%d,%s)", cst, cstlen, pregnames[rdisp_n]);
else if ((x & MODE) == INDEXB)
/* Always take low half of reg. */
outfn (stream, "@(0x%x:%d,%s.b)", cst, cstlen,
regnames[rdisp_n < 8 ? rdisp_n + 8 : rdisp_n]);
else if ((x & MODE) == INDEXW)
/* Always take low half of reg. */
outfn (stream, "@(0x%x:%d,%s.w)", cst, cstlen,
wregnames[rdisp_n < 8 ? rdisp_n : rdisp_n - 8]);
else if ((x & MODE) == INDEXL)
outfn (stream, "@(0x%x:%d,%s.l)", cst, cstlen, lregnames[rdisp_n]);
else if (x & CTRL)
outfn (stream, "%s", cregnames[rn]);
else if ((x & MODE) == CCR)
outfn (stream, "ccr");
else if ((x & MODE) == EXR)
outfn (stream, "exr");
else if ((x & MODE) == MACREG)
outfn (stream, "mac%c", cst ? 'l' : 'h');
else
/* xgettext:c-format */
outfn (stream, _("Hmmmm 0x%x"), x);
}
static unsigned int
bfd_h8_disassemble (bfd_vma addr, disassemble_info *info, int mach)
{
/* Find the first entry in the table for this opcode. */
int regno[3] = { 0, 0, 0 };
int dispregno[3] = { 0, 0, 0 };
int cst[3] = { 0, 0, 0 };
int cstlen[3] = { 0, 0, 0 };
static bfd_boolean init = 0;
const struct h8_instruction *qi;
char const **pregnames = mach != 0 ? lregnames : wregnames;
int status;
unsigned int maxlen;
unsigned char data[MAX_CODE_NIBBLES / 2];
void *stream = info->stream;
fprintf_ftype outfn = info->fprintf_func;
if (!init)
{
bfd_h8_disassemble_init ();
init = 1;
}
status = info->read_memory_func (addr, data, 2, info);
if (status != 0)
{
info->memory_error_func (status, addr, info);
return -1;
}
for (maxlen = 2; maxlen < sizeof (data); maxlen += 2)
{
status = info->read_memory_func (addr + maxlen, data + maxlen, 2, info);
if (status != 0)
break;
}
/* Find the exact opcode/arg combo. */
for (qi = h8_instructions; qi->opcode->name; qi++)
{
const struct h8_opcode *q;
const op_type *nib;
unsigned int len;
op_type looking_for;
if (qi->length > maxlen)
continue;
q = qi->opcode;
nib = q->data.nib;
len = 0;
while ((looking_for = *nib) != (op_type) E)
{
int thisnib;
int opnr;
OPCODES_ASSERT (len / 2 < maxlen);
thisnib = data[len / 2];
thisnib = (len & 1) ? (thisnib & 0xf) : ((thisnib / 16) & 0xf);
opnr = ((looking_for & OP3) == OP3 ? 2
: (looking_for & DST) == DST ? 1 : 0);
if (looking_for < 16 && looking_for >= 0)
{
if (looking_for != thisnib)
goto fail;
}
else
{
if ((int) looking_for & (int) B31)
{
if (!((thisnib & 0x8) != 0))
goto fail;
looking_for = (op_type) ((int) looking_for & ~(int) B31);
thisnib &= 0x7;
}
else if ((int) looking_for & (int) B30)
{
if (!((thisnib & 0x8) == 0))
goto fail;
looking_for = (op_type) ((int) looking_for & ~(int) B30);
}
if ((int) looking_for & (int) B21)
{
if (!((thisnib & 0x4) != 0))
goto fail;
looking_for = (op_type) ((int) looking_for & ~(int) B21);
thisnib &= 0xb;
}
else if ((int) looking_for & (int) B20)
{
if (!((thisnib & 0x4) == 0))
goto fail;
looking_for = (op_type) ((int) looking_for & ~(int) B20);
}
if ((int) looking_for & (int) B11)
{
if (!((thisnib & 0x2) != 0))
goto fail;
looking_for = (op_type) ((int) looking_for & ~(int) B11);
thisnib &= 0xd;
}
else if ((int) looking_for & (int) B10)
{
if (!((thisnib & 0x2) == 0))
goto fail;
looking_for = (op_type) ((int) looking_for & ~(int) B10);
}
if ((int) looking_for & (int) B01)
{
if (!((thisnib & 0x1) != 0))
goto fail;
looking_for = (op_type) ((int) looking_for & ~(int) B01);
thisnib &= 0xe;
}
else if ((int) looking_for & (int) B00)
{
if (!((thisnib & 0x1) == 0))
goto fail;
looking_for = (op_type) ((int) looking_for & ~(int) B00);
}
if (looking_for & IGNORE)
{
/* Hitachi has declared that IGNORE must be zero. */
if (thisnib != 0)
goto fail;
}
else if ((looking_for & MODE) == DATA)
{
; /* Skip embedded data. */
}
else if ((looking_for & MODE) == DBIT)
{
/* Exclude adds/subs by looking at bit 0 and 2, and
make sure the operand size, either w or l,
matches by looking at bit 1. */
if ((looking_for & 7) != (thisnib & 7))
goto fail;
cst[opnr] = (thisnib & 0x8) ? 2 : 1;
}
else if ((looking_for & MODE) == DISP
|| (looking_for & MODE) == ABS
|| (looking_for & MODE) == PCREL
|| (looking_for & MODE) == INDEXB
|| (looking_for & MODE) == INDEXW
|| (looking_for & MODE) == INDEXL)
{
int extra;
switch (looking_for & SIZE)
{
case L_16:
case L_16U:
extra = 1;
break;
case L_32:
extra = 3;
break;
default:
extra = 0;
break;
}
OPCODES_ASSERT (len / 2 + extra < maxlen);
extract_immediate (stream, looking_for, thisnib,
data + len / 2, cst + opnr,
cstlen + opnr, q);
/* Even address == bra, odd == bra/s. */
if (q->how == O (O_BRAS, SB))
cst[opnr] -= 1;
}
else if ((looking_for & MODE) == REG
|| (looking_for & MODE) == LOWREG
|| (looking_for & MODE) == IND
|| (looking_for & MODE) == PREINC
|| (looking_for & MODE) == POSTINC
|| (looking_for & MODE) == PREDEC
|| (looking_for & MODE) == POSTDEC)
{
regno[opnr] = thisnib;
}
else if (looking_for & CTRL) /* Control Register. */
{
thisnib &= 7;
if (((looking_for & MODE) == CCR && (thisnib != C_CCR))
|| ((looking_for & MODE) == EXR && (thisnib != C_EXR))
|| ((looking_for & MODE) == MACH && (thisnib != C_MACH))
|| ((looking_for & MODE) == MACL && (thisnib != C_MACL))
|| ((looking_for & MODE) == VBR && (thisnib != C_VBR))
|| ((looking_for & MODE) == SBR && (thisnib != C_SBR)))
goto fail;
if (((looking_for & MODE) == CCR_EXR
&& (thisnib != C_CCR && thisnib != C_EXR))
|| ((looking_for & MODE) == VBR_SBR
&& (thisnib != C_VBR && thisnib != C_SBR))
|| ((looking_for & MODE) == MACREG
&& (thisnib != C_MACH && thisnib != C_MACL)))
goto fail;
if (((looking_for & MODE) == CC_EX_VB_SB
&& (thisnib != C_CCR && thisnib != C_EXR
&& thisnib != C_VBR && thisnib != C_SBR)))
goto fail;
regno[opnr] = thisnib;
}
else if ((looking_for & SIZE) == L_5)
{
cst[opnr] = data[len / 2] & 31;
cstlen[opnr] = 5;
}
else if ((looking_for & SIZE) == L_4)
{
cst[opnr] = thisnib;
cstlen[opnr] = 4;
}
else if ((looking_for & SIZE) == L_16
|| (looking_for & SIZE) == L_16U)
{
OPCODES_ASSERT (len / 2 + 1 < maxlen);
cst[opnr] = (data[len / 2]) * 256 + data[(len + 2) / 2];
cstlen[opnr] = 16;
}
else if ((looking_for & MODE) == MEMIND)
{
cst[opnr] = data[1];
}
else if ((looking_for & MODE) == VECIND)
{
cst[opnr] = data[1] & 0x7f;
}
else if ((looking_for & SIZE) == L_32)
{
unsigned int i = len / 2;
OPCODES_ASSERT (i + 3 < maxlen);
cst[opnr] = (((unsigned) data[i] << 24)
| (data[i + 1] << 16)
| (data[i + 2] << 8)
| (data[i + 3]));
cstlen[opnr] = 32;
}
else if ((looking_for & SIZE) == L_24)
{
unsigned int i = len / 2;
OPCODES_ASSERT (i + 2 < maxlen);
cst[opnr] =
(data[i] << 16) | (data[i + 1] << 8) | (data[i + 2]);
cstlen[opnr] = 24;
}
else if (looking_for & DISPREG)
{
dispregno[opnr] = thisnib & 7;
}
else if ((looking_for & MODE) == KBIT)
{
switch (thisnib)
{
case 9:
cst[opnr] = 4;
break;
case 8:
cst[opnr] = 2;
break;
case 0:
cst[opnr] = 1;
break;
default:
goto fail;
}
}
else if ((looking_for & SIZE) == L_8)
{
cstlen[opnr] = 8;
cst[opnr] = data[len / 2];
}
else if ((looking_for & SIZE) == L_3
|| (looking_for & SIZE) == L_3NZ)
{
cst[opnr] = thisnib & 0x7;
if (cst[opnr] == 0 && (looking_for & SIZE) == L_3NZ)
goto fail;
}
else if ((looking_for & SIZE) == L_2)
{
cstlen[opnr] = 2;
cst[opnr] = thisnib & 0x3;
}
else if ((looking_for & MODE) == MACREG)
{
cst[opnr] = (thisnib == 3);
}
else
/* xgettext:c-format */
outfn (stream, _("Don't understand 0x%x \n"), looking_for);
}
len++;
nib++;
}
outfn (stream, "%s\t", q->name);
/* Gross. Disgusting. */
if (strcmp (q->name, "ldm.l") == 0)
{
int count, high;
count = (data[1] / 16) & 0x3;
high = regno[1];
outfn (stream, "@sp+,er%d-er%d", high - count, high);
return qi->length;
}
if (strcmp (q->name, "stm.l") == 0)
{
int count, low;
count = (data[1] / 16) & 0x3;
low = regno[0];
outfn (stream, "er%d-er%d,@-sp", low, low + count);
return qi->length;
}
if (strcmp (q->name, "rte/l") == 0
|| strcmp (q->name, "rts/l") == 0)
{
if (regno[0] == 0)
outfn (stream, "er%d", regno[1]);
else
outfn (stream, "er%d-er%d", regno[1] - regno[0],
regno[1]);
return qi->length;
}
if (CONST_STRNEQ (q->name, "mova"))
{
const op_type *args = q->args.nib;
if (args[1] == (op_type) E)
{
/* Short form. */
print_one_arg (info, addr, args[0], cst[0],
cstlen[0], dispregno[0], regno[0],
pregnames, qi->length);
outfn (stream, ",er%d", dispregno[0]);
}
else
{
outfn (stream, "@(0x%x:%d,", cst[0], cstlen[0]);
print_one_arg (info, addr, args[1], cst[1],
cstlen[1], dispregno[1], regno[1],
pregnames, qi->length);
outfn (stream, ".%c),",
(args[0] & MODE) == INDEXB ? 'b' : 'w');
print_one_arg (info, addr, args[2], cst[2],
cstlen[2], dispregno[2], regno[2],
pregnames, qi->length);
}
return qi->length;
}
/* Fill in the args. */
{
const op_type *args = q->args.nib;
int hadone = 0;
int nargs;
/* Special case handling for the adds and subs instructions
since in H8 mode thay can only take the r0-r7 registers
but in other (higher) modes they can take the er0-er7
registers as well. */
if (strcmp (qi->opcode->name, "adds") == 0
|| strcmp (qi->opcode->name, "subs") == 0)
{
outfn (stream, "#%d,%s", cst[0], pregnames[regno[1] & 0x7]);
return qi->length;
}
for (nargs = 0;
nargs < 3 && args[nargs] != (op_type) E;
nargs++)
{
int x = args[nargs];
if (hadone)
outfn (stream, ",");
print_one_arg (info, addr, x,
cst[nargs], cstlen[nargs],
dispregno[nargs], regno[nargs],
pregnames, qi->length);
hadone = 1;
}
}
return qi->length;
fail:
;
}
/* Fell off the end. */
outfn (stream, ".word\tH'%x,H'%x", data[0], data[1]);
return 2;
}
int
print_insn_h8300 (bfd_vma addr, disassemble_info *info)
{
return bfd_h8_disassemble (addr, info, 0);
}
int
print_insn_h8300h (bfd_vma addr, disassemble_info *info)
{
return bfd_h8_disassemble (addr, info, 1);
}
int
print_insn_h8300s (bfd_vma addr, disassemble_info *info)
{
return bfd_h8_disassemble (addr, info, 2);
}