binutils-gdb/gas/config/tc-m32r.c
Doug Evans f2980bb478 * cgen.c (cgen_asm_finish_insn): New arg relax_p. All callers updated.
* config/tc-m32r.c (assemble_parallel_insn): No need to try
	non-relaxable variant any more.  Simplify test for nop insn.
	(md_assemble): Only scan operands if m32rx.  Set orig_insn in case
	scan of operands yields an insn different from original (e.g. a macro).
	Fix call to can_make_parallel.
1998-04-27 19:36:06 +00:00

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/* tc-m32r.c -- Assembler for the Mitsubishi M32R.
Copyright (C) 1996, 1997, 1998 Free Software Foundation.
This file is part of GAS, the GNU Assembler.
GAS 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, or (at your option)
any later version.
GAS 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 GAS; see the file COPYING. If not, write to
the Free Software Foundation, 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA. */
#include <stdio.h>
#include <ctype.h>
#include "as.h"
#include "subsegs.h"
#include "symcat.h"
#include "cgen-opc.h"
/* Structure to hold all of the different components describing an individual instruction. */
typedef struct
{
const CGEN_INSN * insn;
const CGEN_INSN * orig_insn;
CGEN_FIELDS fields;
#ifdef CGEN_INT_INSN
cgen_insn_t buffer [CGEN_MAX_INSN_SIZE / sizeof (cgen_insn_t)];
#else
char buffer [CGEN_MAX_INSN_SIZE];
#endif
char * addr;
fragS * frag;
int indices [MAX_OPERAND_INSTANCES];
}
m32r_insn;
/* prev_insn.insn is non-null if last insn was a 16 bit insn on a 32 bit
boundary (i.e. was the first of two 16 bit insns). */
static m32r_insn prev_insn;
/* Non-zero if we've seen a relaxable insn since the last 32 bit
alignment request. */
static int seen_relaxable_p = 0;
/* Non-zero if -relax specified, in which case sufficient relocs are output
for the linker to do relaxing.
We do simple forms of relaxing internally, but they are always done.
This flag does not apply to them. */
static int m32r_relax;
/* If non-NULL, pointer to cpu description file to read.
This allows runtime additions to the assembler. */
static char * m32r_cpu_desc;
/* start-sanitize-m32rx */
/* Non-zero if -m32rx has been specified, in which case support for the
extended M32RX instruction set should be enabled. */
static int enable_m32rx = 0;
/* Non-zero if the programmer should be warned when an explicit parallel
instruction might have constraint violations. */
static int warn_explicit_parallel_conflicts = 1;
/* start-sanitize-phase2-m32rx */
/* Non-zero if insns can be made parallel. */
static int optimize;
/* end-sanitize-phase2-m32rx */
/* end-sanitize-m32rx */
/* stuff for .scomm symbols. */
static segT sbss_section;
static asection scom_section;
static asymbol scom_symbol;
const char comment_chars[] = ";";
const char line_comment_chars[] = "#";
const char line_separator_chars[] = "";
const char EXP_CHARS[] = "eE";
const char FLT_CHARS[] = "dD";
/* Relocations against symbols are done in two
parts, with a HI relocation and a LO relocation. Each relocation
has only 16 bits of space to store an addend. This means that in
order for the linker to handle carries correctly, it must be able
to locate both the HI and the LO relocation. This means that the
relocations must appear in order in the relocation table.
In order to implement this, we keep track of each unmatched HI
relocation. We then sort them so that they immediately precede the
corresponding LO relocation. */
struct m32r_hi_fixup
{
struct m32r_hi_fixup * next; /* Next HI fixup. */
fixS * fixp; /* This fixup. */
segT seg; /* The section this fixup is in. */
};
/* The list of unmatched HI relocs. */
static struct m32r_hi_fixup * m32r_hi_fixup_list;
/* start-sanitize-m32rx */
static void
allow_m32rx (on)
int on;
{
enable_m32rx = on;
if (stdoutput != NULL)
bfd_set_arch_mach (stdoutput, TARGET_ARCH,
enable_m32rx ? bfd_mach_m32rx : bfd_mach_m32r);
}
/* end-sanitize-m32rx */
#define M32R_SHORTOPTS ""
/* start-sanitize-phase2-m32rx */
#undef M32R_SHORTOPTS
#define M32R_SHORTOPTS "O"
/* end-sanitize-phase2-m32rx */
const char * md_shortopts = M32R_SHORTOPTS;
struct option md_longopts[] =
{
/* start-sanitize-m32rx */
#define OPTION_M32RX (OPTION_MD_BASE)
{"m32rx", no_argument, NULL, OPTION_M32RX},
#define OPTION_WARN (OPTION_MD_BASE + 1)
{"warn-explicit-parallel-conflicts", no_argument, NULL, OPTION_WARN},
{"Wp", no_argument, NULL, OPTION_WARN},
#define OPTION_NO_WARN (OPTION_MD_BASE + 2)
{"no-warn-explicit-parallel-conflicts", no_argument, NULL, OPTION_NO_WARN},
{"Wnp", no_argument, NULL, OPTION_NO_WARN},
/* end-sanitize-m32rx */
#if 0 /* not supported yet */
#define OPTION_RELAX (OPTION_MD_BASE + 3)
{"relax", no_argument, NULL, OPTION_RELAX},
#define OPTION_CPU_DESC (OPTION_MD_BASE + 4)
{"cpu-desc", required_argument, NULL, OPTION_CPU_DESC},
#endif
{NULL, no_argument, NULL, 0}
};
size_t md_longopts_size = sizeof (md_longopts);
int
md_parse_option (c, arg)
int c;
char * arg;
{
switch (c)
{
/* start-sanitize-m32rx */
/* start-sanitize-phase2-m32rx */
case 'O':
optimize = 1;
break;
/* end-sanitize-phase2-m32rx */
case OPTION_M32RX:
allow_m32rx (1);
break;
case OPTION_WARN:
warn_explicit_parallel_conflicts = 1;
break;
case OPTION_NO_WARN:
warn_explicit_parallel_conflicts = 0;
break;
/* end-sanitize-m32rx */
#if 0 /* not supported yet */
case OPTION_RELAX:
m32r_relax = 1;
break;
case OPTION_CPU_DESC:
m32r_cpu_desc = arg;
break;
#endif
default:
return 0;
}
return 1;
}
void
md_show_usage (stream)
FILE * stream;
{
/* start-sanitize-m32rx */
fprintf (stream, _("M32R/X specific command line options:\n"));
fprintf (stream, _("\
--m32rx support the extended m32rx instruction set\n"));
/* start-sanitize-phase2-m32rx */
fprintf (stream, _("\
-O try to combine instructions in parallel\n"));
/* end-sanitize-phase2-m32rx */
fprintf (stream, _("\
--warn-explicit-parallel-conflicts warn when parallel instrucitons violate contraints\n"));
fprintf (stream, _("\
--no-warn-explicit-parallel-conflicts do not warn when parallel instrucitons violate contraints\n"));
fprintf (stream, _("\
--Wp synonym for --warn-explicit-parallel-conflicts\n"));
fprintf (stream, _("\
--Wnp synonym for --no-warn-explicit-parallel-conflicts\n"));
/* end-sanitize-m32rx */
#if 0
fprintf (stream, _("\
--relax create linker relaxable code\n"));
fprintf (stream, _("\
--cpu-desc provide runtime cpu description file\n"));
#endif
}
static void fill_insn PARAMS ((int));
static void m32r_scomm PARAMS ((int));
/* Set by md_assemble for use by m32r_fill_insn. */
static subsegT prev_subseg;
static segT prev_seg;
/* The target specific pseudo-ops which we support. */
const pseudo_typeS md_pseudo_table[] =
{
{ "word", cons, 4 },
{ "fillinsn", fill_insn, 0 },
{ "scomm", m32r_scomm, 0 },
/* start-sanitize-m32rx */
{ "m32r", allow_m32rx, 0},
{ "m32rx", allow_m32rx, 1},
/* end-sanitize-m32rx */
{ NULL, NULL, 0 }
};
/* FIXME: Should be machine generated. */
#define NOP_INSN 0x7000
#define PAR_NOP_INSN 0xf000 /* can only be used in 2nd slot */
/* When we align the .text section, insert the correct NOP pattern.
N is the power of 2 alignment. LEN is the length of pattern FILL.
MAX is the maximum number of characters to skip when doing the alignment,
or 0 if there is no maximum. */
int
m32r_do_align (n, fill, len, max)
int n;
const char * fill;
int len;
int max;
{
if ((fill == NULL || (* fill == 0 && len == 1))
&& (now_seg->flags & SEC_CODE) != 0
/* Only do this special handling if aligning to at least a
4 byte boundary. */
&& n > 1
/* Only do this special handling if we're allowed to emit at
least two bytes. */
&& (max == 0 || max > 1))
{
static const unsigned char nop_pattern[] = { 0xf0, 0x00 };
#if 0
/* First align to a 2 byte boundary, in case there is an odd .byte. */
/* FIXME: How much memory will cause gas to use when assembling a big
program? Perhaps we can avoid the frag_align call? */
frag_align (1, 0, 0);
#endif
/* Next align to a 4 byte boundary (we know n >= 2) using a parallel
nop. */
frag_align_pattern (2, nop_pattern, sizeof nop_pattern, 0);
/* If doing larger alignments use a repeating sequence of appropriate
nops. */
if (n > 2)
{
static const unsigned char multi_nop_pattern[] =
{ 0x70, 0x00, 0xf0, 0x00 };
frag_align_pattern (n, multi_nop_pattern, sizeof multi_nop_pattern,
max ? max - 2 : 0);
}
return 1;
}
return 0;
}
static void
assemble_nop (opcode)
int opcode;
{
char * f = frag_more (2);
md_number_to_chars (f, opcode, 2);
}
/* If the last instruction was the first of 2 16 bit insns,
output a nop to move the PC to a 32 bit boundary.
This is done via an alignment specification since branch relaxing
may make it unnecessary.
Internally, we need to output one of these each time a 32 bit insn is
seen after an insn that is relaxable. */
static void
fill_insn (ignore)
int ignore;
{
(void) m32r_do_align (2, NULL, 0, 0);
prev_insn.insn = NULL;
seen_relaxable_p = 0;
}
/* Cover function to fill_insn called after a label and at end of assembly.
The result is always 1: we're called in a conditional to see if the
current line is a label. */
int
m32r_fill_insn (done)
int done;
{
if (prev_seg != NULL)
{
segT seg = now_seg;
subsegT subseg = now_subseg;
subseg_set (prev_seg, prev_subseg);
fill_insn (0);
subseg_set (seg, subseg);
}
return 1;
}
void
md_begin ()
{
flagword applicable;
segT seg;
subsegT subseg;
/* Initialize the `cgen' interface. */
/* This is a callback from cgen to gas to parse operands. */
cgen_parse_operand_fn = cgen_parse_operand;
/* Set the machine number and endian. */
CGEN_SYM (init_asm) (0 /* mach number */,
target_big_endian ?
CGEN_ENDIAN_BIG : CGEN_ENDIAN_LITTLE);
#if 0 /* not supported yet */
/* If a runtime cpu description file was provided, parse it. */
if (m32r_cpu_desc != NULL)
{
const char * errmsg;
errmsg = cgen_read_cpu_file (m32r_cpu_desc);
if (errmsg != NULL)
as_bad ("%s: %s", m32r_cpu_desc, errmsg);
}
#endif
/* Save the current subseg so we can restore it [it's the default one and
we don't want the initial section to be .sbss]. */
seg = now_seg;
subseg = now_subseg;
/* The sbss section is for local .scomm symbols. */
sbss_section = subseg_new (".sbss", 0);
/* This is copied from perform_an_assembly_pass. */
applicable = bfd_applicable_section_flags (stdoutput);
bfd_set_section_flags (stdoutput, sbss_section, applicable & SEC_ALLOC);
#if 0 /* What does this do? [see perform_an_assembly_pass] */
seg_info (bss_section)->bss = 1;
#endif
subseg_set (seg, subseg);
/* We must construct a fake section similar to bfd_com_section
but with the name .scommon. */
scom_section = bfd_com_section;
scom_section.name = ".scommon";
scom_section.output_section = & scom_section;
scom_section.symbol = & scom_symbol;
scom_section.symbol_ptr_ptr = & scom_section.symbol;
scom_symbol = * bfd_com_section.symbol;
scom_symbol.name = ".scommon";
scom_symbol.section = & scom_section;
/* start-sanitize-m32rx */
allow_m32rx (enable_m32rx);
/* end-sanitize-m32rx */
}
/* start-sanitize-m32rx */
#define OPERAND_IS_COND_BIT(operand, indices, index) \
(CGEN_OPERAND_INSTANCE_HW (operand)->type == HW_H_COND \
|| (CGEN_OPERAND_INSTANCE_HW (operand)->type == HW_H_CR \
&& (indices [index] == 0 || indices [index] == 1)))
/* Returns true if an output of instruction 'a' is referenced by an operand
of instruction 'b'. If 'check_outputs' is true then b's outputs are
checked, otherwise its inputs are examined. */
static int
first_writes_to_seconds_operands (a, b, check_outputs)
m32r_insn * a;
m32r_insn * b;
const int check_outputs;
{
const CGEN_OPERAND_INSTANCE * a_operands = CGEN_INSN_OPERANDS (a->insn);
const CGEN_OPERAND_INSTANCE * b_ops = CGEN_INSN_OPERANDS (b->insn);
int a_index;
/* If at least one of the instructions takes no operands, then there is
nothing to check. There really are instructions without operands,
eg 'nop'. */
if (a_operands == NULL || b_ops == NULL)
return 0;
/* Scan the operand list of 'a' looking for an output operand. */
for (a_index = 0;
CGEN_OPERAND_INSTANCE_TYPE (a_operands) != CGEN_OPERAND_INSTANCE_END;
a_index ++, a_operands ++)
{
if (CGEN_OPERAND_INSTANCE_TYPE (a_operands) == CGEN_OPERAND_INSTANCE_OUTPUT)
{
int b_index;
const CGEN_OPERAND_INSTANCE * b_operands = b_ops;
/* Special Case:
The Condition bit 'C' is a shadow of the CBR register (control
register 1) and also a shadow of bit 31 of the program status
word (control register 0). For now this is handled here, rather
than by cgen.... */
if (OPERAND_IS_COND_BIT (a_operands, a->indices, a_index))
{
/* Scan operand list of 'b' looking for another reference to the
condition bit, which goes in the right direction. */
for (b_index = 0;
CGEN_OPERAND_INSTANCE_TYPE (b_operands) != CGEN_OPERAND_INSTANCE_END;
b_index ++, b_operands ++)
{
if ((CGEN_OPERAND_INSTANCE_TYPE (b_operands) ==
(check_outputs ? CGEN_OPERAND_INSTANCE_OUTPUT : CGEN_OPERAND_INSTANCE_INPUT))
&& OPERAND_IS_COND_BIT (b_operands, b->indices, b_index))
return 1;
}
}
else
{
/* Scan operand list of 'b' looking for an operand that references
the same hardware element, and which goes in the right direction. */
for (b_index = 0;
CGEN_OPERAND_INSTANCE_TYPE (b_operands) != CGEN_OPERAND_INSTANCE_END;
b_index ++, b_operands ++)
{
if ((CGEN_OPERAND_INSTANCE_TYPE (b_operands) ==
(check_outputs ? CGEN_OPERAND_INSTANCE_OUTPUT : CGEN_OPERAND_INSTANCE_INPUT))
&& (CGEN_OPERAND_INSTANCE_HW (b_operands) == CGEN_OPERAND_INSTANCE_HW (a_operands))
&& (a->indices [a_index] == b->indices [b_index]))
return 1;
}
}
}
}
return 0;
}
/* Returns true if the insn can (potentially) alter the program counter. */
static int
writes_to_pc (a)
m32r_insn * a;
{
#if 0 /* Once PC operands are working.... */
const CGEN_OPERAND_INSTANCE * a_operands == CGEN_INSN_OPERANDS (a->insn);
if (a_operands == NULL)
return 0;
while (CGEN_OPERAND_INSTANCE_TYPE (a_operands) != CGEN_OPERAND_INSTANCE_END)
{
if (CGEN_OPERAND_INSTANCE_OPERAND (a_operands) != NULL
&& CGEN_OPERAND_INDEX (CGEN_OPERAND_INSTANCE_OPERAND (a_operands)) == M32R_OPERAND_PC)
return 1;
a_operands ++;
}
#else
if (CGEN_INSN_ATTR (a->insn, CGEN_INSN_UNCOND_CTI)
|| CGEN_INSN_ATTR (a->insn, CGEN_INSN_COND_CTI))
return 1;
#endif
return 0;
}
/* Returns NULL if the two 16 bit insns can be executed in parallel,
otherwise it returns a pointer to an error message explaining why not. */
static const char *
can_make_parallel (a, b)
m32r_insn * a;
m32r_insn * b;
{
PIPE_ATTR a_pipe;
PIPE_ATTR b_pipe;
/* Make sure the instructions are the right length. */
if ( CGEN_FIELDS_BITSIZE (& a->fields) != 16
|| CGEN_FIELDS_BITSIZE (& b->fields) != 16)
abort();
if (first_writes_to_seconds_operands (a, b, true))
return _("Instructions write to the same destination register.");
a_pipe = CGEN_INSN_ATTR (a->insn, CGEN_INSN_PIPE);
b_pipe = CGEN_INSN_ATTR (b->insn, CGEN_INSN_PIPE);
/* Make sure that the instructions use the correct execution pipelines. */
if ( a_pipe == PIPE_NONE
|| b_pipe == PIPE_NONE)
return _("Instructions do not use parallel execution pipelines.");
/* Leave this test for last, since it is the only test that can
go away if the instructions are swapped, and we want to make
sure that any other errors are detected before this happens. */
if ( a_pipe == PIPE_S
|| b_pipe == PIPE_O)
return _("Instructions share the same execution pipeline");
return NULL;
}
#ifdef CGEN_INT_INSN
static void
make_parallel (buffer)
cgen_insn_t * buffer;
{
/* Force the top bit of the second insn to be set. */
bfd_vma value;
if (CGEN_CURRENT_ENDIAN == CGEN_ENDIAN_BIG)
{
value = bfd_getb16 ((bfd_byte *) buffer);
value |= 0x8000;
bfd_putb16 (value, (char *) buffer);
}
else
{
value = bfd_getl16 ((bfd_byte *) buffer);
value |= 0x8000;
bfd_putl16 (value, (char *) buffer);
}
}
#else
static void
make_parallel (buffer)
char * buffer;
{
/* Force the top bit of the second insn to be set. */
buffer [CGEN_CURRENT_ENDIAN == CGEN_ENDIAN_BIG ? 0 : 1] |= 0x80;
}
#endif /* ! CGEN_INT_INSN */
static void
assemble_parallel_insn (str, str2)
char * str;
char * str2;
{
char * str3;
m32r_insn first;
m32r_insn second;
char * errmsg;
* str2 = 0; /* Seperate the two instructions. */
/* If there was a previous 16 bit insn, then fill the following 16 bit slot,
so that the parallel instruction will start on a 32 bit boundary. */
if (prev_insn.insn)
fill_insn (0);
/* Parse the first instruction. */
if (! (first.insn = CGEN_SYM (assemble_insn)
(str, & first.fields, first.buffer, & errmsg)))
{
as_bad (errmsg);
return;
}
if (! enable_m32rx
/* FIXME: Need standard macro to perform this test. */
&& CGEN_INSN_ATTR (first.insn, CGEN_INSN_MACH) == (1 << MACH_M32RX))
{
as_bad (_("instruction '%s' is for the M32RX only"), str);
return;
}
/* Check to see if this is an allowable parallel insn. */
if (CGEN_INSN_ATTR (first.insn, CGEN_INSN_PIPE) == PIPE_NONE)
{
as_bad (_("instruction '%s' cannot be executed in parallel."), str);
return;
}
*str2 = '|'; /* Restore the original assembly text, just in case it is needed. */
str3 = str; /* Save the original string pointer. */
str = str2 + 2; /* Advanced past the parsed string. */
str2 = str3; /* Remember the entire string in case it is needed for error messages. */
/* Preserve any fixups that have been generated and reset the list to empty. */
cgen_save_fixups();
/* Get the indices of the operands of the instruction. */
/* FIXME: CGEN_FIELDS is already recorded, but relying on that fact
doesn't seem right. Perhaps allow passing fields like we do insn. */
/* FIXME: ALIAS insns do not have operands, so we use this function
to find the equivalent insn and overwrite the value stored in our
structure. We still need the original insn, however, since this
may have certain attributes that are not present in the unaliased
version (eg relaxability). When aliases behave differently this
may have to change. */
first.orig_insn = first.insn;
first.insn = m32r_cgen_lookup_get_insn_operands (NULL,
bfd_getb16 ((char *) first.buffer),
16,
first.indices);
if (first.insn == NULL)
as_fatal (_("internal error: m32r_cgen_lookup_get_insn_operands failed for first insn"));
/* Parse the second instruction. */
if (! (second.insn = CGEN_SYM (assemble_insn)
(str, & second.fields, second.buffer, & errmsg)))
{
as_bad (errmsg);
return;
}
/* Check it. */
if (! enable_m32rx
&& CGEN_INSN_ATTR (second.insn, CGEN_INSN_MACH) == (1 << MACH_M32RX))
{
as_bad (_("instruction '%s' is for the M32RX only"), str);
return;
}
/* Check to see if this is an allowable parallel insn. */
if (CGEN_INSN_ATTR (second.insn, CGEN_INSN_PIPE) == PIPE_NONE)
{
as_bad (_("instruction '%s' cannot be executed in parallel."), str);
return;
}
if (! enable_m32rx)
{
if (CGEN_INSN_NUM (first.insn) != M32R_INSN_NOP
&& CGEN_INSN_NUM (second.insn) != M32R_INSN_NOP)
{
as_bad (_("'%s': only the NOP instruction can be issued in parallel on the m32r"), str2);
return;
}
}
/* Get the indices of the operands of the instruction. */
second.orig_insn = second.insn;
second.insn = m32r_cgen_lookup_get_insn_operands (NULL,
bfd_getb16 ((char *) second.buffer),
16,
second.indices);
if (second.insn == NULL)
as_fatal (_("internal error: m32r_cgen_lookup_get_insn_operands failed for second insn"));
/* We assume that if the first instruction writes to a register that is
read by the second instruction it is because the programmer intended
this to happen, (after all they have explicitly requested that these
two instructions be executed in parallel). Although if the global
variable warn_explicit_parallel_conflicts is true then we do generate
a warning message. Similarly we assume that parallel branch and jump
instructions are deliberate and should not produce errors. */
if (warn_explicit_parallel_conflicts)
{
if (first_writes_to_seconds_operands (& first, & second, false))
as_warn (_("%s: output of 1st instruction is the same as an input to 2nd instruction - is this intentional ?"), str2);
if (first_writes_to_seconds_operands (& second, & first, false))
as_warn (_("%s: output of 2nd instruction is the same as an input to 1st instruction - is this intentional ?"), str2);
}
if ((errmsg = (char *) can_make_parallel (& first, & second)) == NULL)
{
/* Get the fixups for the first instruction. */
cgen_swap_fixups ();
/* Write it out. */
(void) cgen_asm_finish_insn (first.orig_insn, first.buffer,
CGEN_FIELDS_BITSIZE (& first.fields), 0);
/* Force the top bit of the second insn to be set. */
make_parallel (second.buffer);
/* Get its fixups. */
cgen_restore_fixups ();
/* Write it out. */
(void) cgen_asm_finish_insn (second.orig_insn, second.buffer,
CGEN_FIELDS_BITSIZE (& second.fields), 0);
}
/* Try swapping the instructions to see if they work that way. */
else if (can_make_parallel (& second, & first) == NULL)
{
/* Write out the second instruction first. */
(void) cgen_asm_finish_insn (second.orig_insn, second.buffer,
CGEN_FIELDS_BITSIZE (& second.fields), 0);
/* Force the top bit of the first instruction to be set. */
make_parallel (first.buffer);
/* Get the fixups for the first instruction. */
cgen_restore_fixups ();
/* Write out the first instruction. */
(void) cgen_asm_finish_insn (first.orig_insn, first.buffer,
CGEN_FIELDS_BITSIZE (& first.fields), 0);
}
else
{
as_bad ("'%s': %s", str2, errmsg);
return;
}
/* Set these so m32r_fill_insn can use them. */
prev_seg = now_seg;
prev_subseg = now_subseg;
}
/* end-sanitize-m32rx */
void
md_assemble (str)
char * str;
{
m32r_insn insn;
char * errmsg;
char * str2 = NULL;
/* Initialize GAS's cgen interface for a new instruction. */
cgen_asm_init_parse ();
/* start-sanitize-m32rx */
/* Look for a parallel instruction seperator. */
if ((str2 = strstr (str, "||")) != NULL)
{
assemble_parallel_insn (str, str2);
return;
}
/* end-sanitize-m32rx */
insn.insn = CGEN_SYM (assemble_insn) (str, & insn.fields, insn.buffer, & errmsg);
if (!insn.insn)
{
as_bad (errmsg);
return;
}
/* start-sanitize-m32rx */
if (! enable_m32rx && CGEN_INSN_ATTR (insn.insn, CGEN_INSN_MACH) == (1 << MACH_M32RX))
{
as_bad (_("instruction '%s' is for the M32RX only"), str);
return;
}
/* end-sanitize-m32rx */
if (CGEN_INSN_BITSIZE (insn.insn) == 32)
{
/* 32 bit insns must live on 32 bit boundaries. */
if (prev_insn.insn || seen_relaxable_p)
{
/* ??? If calling fill_insn too many times turns us into a memory
pig, can we call assemble_nop instead of !seen_relaxable_p? */
fill_insn (0);
}
/* Doesn't really matter what we pass for RELAX_P here. */
(void) cgen_asm_finish_insn (insn.insn, insn.buffer,
CGEN_FIELDS_BITSIZE (& insn.fields), 1);
}
else
{
/* start-sanitize-m32rx */
/* start-sanitize-phase2-m32rx */
int swap = false;
/* end-sanitize-phase2-m32rx */
/* end-sanitize-m32rx */
if (CGEN_INSN_BITSIZE (insn.insn) != 16)
abort();
if (enable_m32rx)
{
/* Get the indices of the operands of the instruction.
FIXME: See assemble_parallel for notes on orig_insn. */
insn.orig_insn = insn.insn;
insn.insn = m32r_cgen_lookup_get_insn_operands (NULL,
bfd_getb16 ((char *) insn.buffer),
16,
insn.indices);
if (insn.insn == NULL)
as_fatal (_("internal error: m32r_cgen_get_insn_operands failed"));
}
else
insn.orig_insn = insn.insn;
/* Keep track of whether we've seen a pair of 16 bit insns.
prev_insn.insn is NULL when we're on a 32 bit boundary. */
if (prev_insn.insn)
{
/* start-sanitize-m32rx */
/* start-sanitize-phase2-m32rx */
/* Look to see if this instruction can be combined with the
previous instruction to make one, parallel, 32 bit instruction.
If the previous instruction (potentially) changed the flow of
program control, then it cannot be combined with the current
instruction. If the current instruction is relaxable, then it
might be replaced with a longer version, so we cannot combine it.
Also if the output of the previous instruction is used as an
input to the current instruction then it cannot be combined.
Otherwise call can_make_parallel() with both orderings of the
instructions to see if they can be combined. */
if ( enable_m32rx
&& optimize
&& CGEN_INSN_ATTR (insn.orig_insn, CGEN_INSN_RELAXABLE) == 0
&& ! writes_to_pc (& prev_insn)
&& ! first_writes_to_seconds_operands (& prev_insn, &insn, false)
)
{
if (can_make_parallel (& prev_insn, & insn) == NULL)
make_parallel (insn.buffer);
else if (can_make_parallel (& insn, & prev_insn) == NULL)
swap = true;
}
/* end-sanitize-phase2-m32rx */
/* end-sanitize-m32rx */
prev_insn.insn = NULL;
}
else
{
prev_insn = insn;
}
/* Record the frag that might be used by this insn. */
insn.frag = frag_now;
insn.addr = cgen_asm_finish_insn (insn.orig_insn, insn.buffer,
CGEN_FIELDS_BITSIZE (& insn.fields),
1 /*relax_p*/);
/* start-sanitize-m32rx */
/* start-sanitize-phase2-m32rx */
if (swap)
{
int tmp;
#define SWAP_BYTES(a,b) tmp = a; a = b; b = tmp
/* Swap the two insns */
SWAP_BYTES (prev_insn.addr [0], insn.addr [0]);
SWAP_BYTES (prev_insn.addr [1], insn.addr [1]);
make_parallel (insn.addr);
/* Swap any relaxable frags recorded for the two insns. */
if (prev_insn.frag->fr_opcode == prev_insn.addr)
prev_insn.frag->fr_opcode = insn.addr;
else if (insn.frag->fr_opcode == insn.addr)
insn.frag->fr_opcode = prev_insn.addr;
}
/* end-sanitize-phase2-m32rx */
/* Record where this instruction was assembled. */
prev_insn.addr = insn.addr;
prev_insn.frag = insn.frag;
/* end-sanitize-m32rx */
/* If the insn needs the following one to be on a 32 bit boundary
(e.g. subroutine calls), fill this insn's slot. */
if (prev_insn.insn != NULL
&& CGEN_INSN_ATTR (insn.orig_insn, CGEN_INSN_FILL_SLOT) != 0)
fill_insn (0);
/* If this is a relaxable insn (can be replaced with a larger version)
mark the fact so that we can emit an alignment directive for a
following 32 bit insn if we see one. */
if (CGEN_INSN_ATTR (insn.orig_insn, CGEN_INSN_RELAXABLE) != 0)
seen_relaxable_p = 1;
}
/* Set these so m32r_fill_insn can use them. */
prev_seg = now_seg;
prev_subseg = now_subseg;
}
/* The syntax in the manual says constants begin with '#'.
We just ignore it. */
void
md_operand (expressionP)
expressionS * expressionP;
{
if (* input_line_pointer == '#')
{
input_line_pointer ++;
expression (expressionP);
}
}
valueT
md_section_align (segment, size)
segT segment;
valueT size;
{
int align = bfd_get_section_alignment (stdoutput, segment);
return ((size + (1 << align) - 1) & (-1 << align));
}
symbolS *
md_undefined_symbol (name)
char * name;
{
return 0;
}
/* .scomm pseudo-op handler.
This is a new pseudo-op to handle putting objects in .scommon.
By doing this the linker won't need to do any work and more importantly
it removes the implicit -G arg necessary to correctly link the object file.
*/
static void
m32r_scomm (ignore)
int ignore;
{
register char * name;
register char c;
register char * p;
offsetT size;
register symbolS * symbolP;
offsetT align;
int align2;
name = input_line_pointer;
c = get_symbol_end ();
/* just after name is now '\0' */
p = input_line_pointer;
* p = c;
SKIP_WHITESPACE ();
if (* input_line_pointer != ',')
{
as_bad (_("Expected comma after symbol-name: rest of line ignored."));
ignore_rest_of_line ();
return;
}
input_line_pointer ++; /* skip ',' */
if ((size = get_absolute_expression ()) < 0)
{
as_warn (_(".SCOMMon length (%ld.) <0! Ignored."), (long) size);
ignore_rest_of_line ();
return;
}
/* The third argument to .scomm is the alignment. */
if (* input_line_pointer != ',')
align = 8;
else
{
++ input_line_pointer;
align = get_absolute_expression ();
if (align <= 0)
{
as_warn (_("ignoring bad alignment"));
align = 8;
}
}
/* Convert to a power of 2 alignment. */
if (align)
{
for (align2 = 0; (align & 1) == 0; align >>= 1, ++ align2)
continue;
if (align != 1)
{
as_bad (_("Common alignment not a power of 2"));
ignore_rest_of_line ();
return;
}
}
else
align2 = 0;
* p = 0;
symbolP = symbol_find_or_make (name);
* p = c;
if (S_IS_DEFINED (symbolP))
{
as_bad (_("Ignoring attempt to re-define symbol `%s'."),
S_GET_NAME (symbolP));
ignore_rest_of_line ();
return;
}
if (S_GET_VALUE (symbolP) && S_GET_VALUE (symbolP) != (valueT) size)
{
as_bad (_("Length of .scomm \"%s\" is already %ld. Not changed to %ld."),
S_GET_NAME (symbolP),
(long) S_GET_VALUE (symbolP),
(long) size);
ignore_rest_of_line ();
return;
}
if (symbolP->local)
{
segT old_sec = now_seg;
int old_subsec = now_subseg;
char * pfrag;
record_alignment (sbss_section, align2);
subseg_set (sbss_section, 0);
if (align2)
frag_align (align2, 0, 0);
if (S_GET_SEGMENT (symbolP) == sbss_section)
symbolP->sy_frag->fr_symbol = 0;
symbolP->sy_frag = frag_now;
pfrag = frag_var (rs_org, 1, 1, (relax_substateT) 0, symbolP, size,
(char *) 0);
* pfrag = 0;
S_SET_SIZE (symbolP, size);
S_SET_SEGMENT (symbolP, sbss_section);
S_CLEAR_EXTERNAL (symbolP);
subseg_set (old_sec, old_subsec);
}
else
{
S_SET_VALUE (symbolP, (valueT) size);
S_SET_ALIGN (symbolP, align2);
S_SET_EXTERNAL (symbolP);
S_SET_SEGMENT (symbolP, & scom_section);
}
demand_empty_rest_of_line ();
}
/* Interface to relax_segment. */
/* FIXME: Build table by hand, get it working, then machine generate. */
const relax_typeS md_relax_table[] =
{
/* The fields are:
1) most positive reach of this state,
2) most negative reach of this state,
3) how many bytes this mode will add to the size of the current frag
4) which index into the table to try if we can't fit into this one. */
/* The first entry must be unused because an `rlx_more' value of zero ends
each list. */
{1, 1, 0, 0},
/* The displacement used by GAS is from the end of the 2 byte insn,
so we subtract 2 from the following. */
/* 16 bit insn, 8 bit disp -> 10 bit range.
This doesn't handle a branch in the right slot at the border:
the "& -4" isn't taken into account. It's not important enough to
complicate things over it, so we subtract an extra 2 (or + 2 in -ve
case). */
{511 - 2 - 2, -512 - 2 + 2, 0, 2 },
/* 32 bit insn, 24 bit disp -> 26 bit range. */
{0x2000000 - 1 - 2, -0x2000000 - 2, 2, 0 },
/* Same thing, but with leading nop for alignment. */
{0x2000000 - 1 - 2, -0x2000000 - 2, 4, 0 }
};
long
m32r_relax_frag (fragP, stretch)
fragS * fragP;
long stretch;
{
/* Address of branch insn. */
long address = fragP->fr_address + fragP->fr_fix - 2;
long growth = 0;
/* Keep 32 bit insns aligned on 32 bit boundaries. */
if (fragP->fr_subtype == 2)
{
if ((address & 3) != 0)
{
fragP->fr_subtype = 3;
growth = 2;
}
}
else if (fragP->fr_subtype == 3)
{
if ((address & 3) == 0)
{
fragP->fr_subtype = 2;
growth = -2;
}
}
else
{
growth = relax_frag (fragP, stretch);
/* Long jump on odd halfword boundary? */
if (fragP->fr_subtype == 2 && (address & 3) != 0)
{
fragP->fr_subtype = 3;
growth += 2;
}
}
return growth;
}
/* Return an initial guess of the length by which a fragment must grow to
hold a branch to reach its destination.
Also updates fr_type/fr_subtype as necessary.
Called just before doing relaxation.
Any symbol that is now undefined will not become defined.
The guess for fr_var is ACTUALLY the growth beyond fr_fix.
Whatever we do to grow fr_fix or fr_var contributes to our returned value.
Although it may not be explicit in the frag, pretend fr_var starts with a
0 value. */
int
md_estimate_size_before_relax (fragP, segment)
fragS * fragP;
segT segment;
{
int old_fr_fix = fragP->fr_fix;
char * opcode = fragP->fr_opcode;
/* The only thing we have to handle here are symbols outside of the
current segment. They may be undefined or in a different segment in
which case linker scripts may place them anywhere.
However, we can't finish the fragment here and emit the reloc as insn
alignment requirements may move the insn about. */
if (S_GET_SEGMENT (fragP->fr_symbol) != segment)
{
/* The symbol is undefined in this segment.
Change the relaxation subtype to the max allowable and leave
all further handling to md_convert_frag. */
fragP->fr_subtype = 2;
#if 0 /* Can't use this, but leave in for illustration. */
/* Change 16 bit insn to 32 bit insn. */
opcode[0] |= 0x80;
/* Increase known (fixed) size of fragment. */
fragP->fr_fix += 2;
/* Create a relocation for it. */
fix_new (fragP, old_fr_fix, 4,
fragP->fr_symbol,
fragP->fr_offset, 1 /* pcrel */,
/* FIXME: Can't use a real BFD reloc here.
cgen_md_apply_fix3 can't handle it. */
BFD_RELOC_M32R_26_PCREL);
/* Mark this fragment as finished. */
frag_wane (fragP);
#else
{
const CGEN_INSN * insn;
int i;
/* Update the recorded insn.
Fortunately we don't have to look very far.
FIXME: Change this to record in the instruction the next higher
relaxable insn to use. */
for (i = 0, insn = fragP->fr_cgen.insn; i < 4; i++, insn++)
{
if ((strcmp (CGEN_INSN_MNEMONIC (insn),
CGEN_INSN_MNEMONIC (fragP->fr_cgen.insn))
== 0)
&& CGEN_INSN_ATTR (insn, CGEN_INSN_RELAX))
break;
}
if (i == 4)
abort ();
fragP->fr_cgen.insn = insn;
return 2;
}
#endif
}
return (fragP->fr_var + fragP->fr_fix - old_fr_fix);
}
/* *fragP has been relaxed to its final size, and now needs to have
the bytes inside it modified to conform to the new size.
Called after relaxation is finished.
fragP->fr_type == rs_machine_dependent.
fragP->fr_subtype is the subtype of what the address relaxed to. */
void
md_convert_frag (abfd, sec, fragP)
bfd * abfd;
segT sec;
fragS * fragP;
{
char * opcode;
char * displacement;
int target_address;
int opcode_address;
int extension;
int addend;
opcode = fragP->fr_opcode;
/* Address opcode resides at in file space. */
opcode_address = fragP->fr_address + fragP->fr_fix - 2;
switch (fragP->fr_subtype)
{
case 1 :
extension = 0;
displacement = & opcode[1];
break;
case 2 :
opcode[0] |= 0x80;
extension = 2;
displacement = & opcode[1];
break;
case 3 :
opcode[2] = opcode[0] | 0x80;
md_number_to_chars (opcode, PAR_NOP_INSN, 2);
opcode_address += 2;
extension = 4;
displacement = & opcode[3];
break;
default :
abort ();
}
if (S_GET_SEGMENT (fragP->fr_symbol) != sec)
{
/* symbol must be resolved by linker */
if (fragP->fr_offset & 3)
as_warn (_("Addend to unresolved symbol not on word boundary."));
addend = fragP->fr_offset >> 2;
}
else
{
/* Address we want to reach in file space. */
target_address = S_GET_VALUE (fragP->fr_symbol) + fragP->fr_offset;
target_address += fragP->fr_symbol->sy_frag->fr_address;
addend = (target_address - (opcode_address & -4)) >> 2;
}
/* Create a relocation for symbols that must be resolved by the linker.
Otherwise output the completed insn. */
if (S_GET_SEGMENT (fragP->fr_symbol) != sec)
{
assert (fragP->fr_subtype != 1);
assert (fragP->fr_cgen.insn != 0);
cgen_record_fixup (fragP,
/* Offset of branch insn in frag. */
fragP->fr_fix + extension - 4,
fragP->fr_cgen.insn,
4 /*length*/,
/* FIXME: quick hack */
#if 0
CGEN_OPERAND_ENTRY (fragP->fr_cgen.opindex),
#else
CGEN_OPERAND_ENTRY (M32R_OPERAND_DISP24),
#endif
fragP->fr_cgen.opinfo,
fragP->fr_symbol, fragP->fr_offset);
}
#define SIZE_FROM_RELAX_STATE(n) ((n) == 1 ? 1 : 3)
md_number_to_chars (displacement, (valueT) addend,
SIZE_FROM_RELAX_STATE (fragP->fr_subtype));
fragP->fr_fix += extension;
}
/* Functions concerning relocs. */
/* The location from which a PC relative jump should be calculated,
given a PC relative reloc. */
long
md_pcrel_from_section (fixP, sec)
fixS * fixP;
segT sec;
{
if (fixP->fx_addsy != (symbolS *) NULL
&& (! S_IS_DEFINED (fixP->fx_addsy)
|| S_GET_SEGMENT (fixP->fx_addsy) != sec))
{
/* The symbol is undefined (or is defined but not in this section).
Let the linker figure it out. */
return 0;
}
return (fixP->fx_frag->fr_address + fixP->fx_where) & -4L;
}
/* Return the bfd reloc type for OPERAND of INSN at fixup FIXP.
Returns BFD_RELOC_NONE if no reloc type can be found.
*FIXP may be modified if desired. */
bfd_reloc_code_real_type
CGEN_SYM (lookup_reloc) (insn, operand, fixP)
const CGEN_INSN * insn;
const CGEN_OPERAND * operand;
fixS * fixP;
{
switch (CGEN_OPERAND_TYPE (operand))
{
case M32R_OPERAND_DISP8 : return BFD_RELOC_M32R_10_PCREL;
case M32R_OPERAND_DISP16 : return BFD_RELOC_M32R_18_PCREL;
case M32R_OPERAND_DISP24 : return BFD_RELOC_M32R_26_PCREL;
case M32R_OPERAND_UIMM24 : return BFD_RELOC_M32R_24;
case M32R_OPERAND_HI16 :
case M32R_OPERAND_SLO16 :
case M32R_OPERAND_ULO16 :
/* If low/high/shigh/sda was used, it is recorded in `opinfo'. */
if (fixP->tc_fix_data.opinfo != 0)
return fixP->tc_fix_data.opinfo;
break;
}
return BFD_RELOC_NONE;
}
/* Record a HI16 reloc for later matching with its LO16 cousin. */
static void
m32r_record_hi16 (reloc_type, fixP, seg)
int reloc_type;
fixS * fixP;
segT seg;
{
struct m32r_hi_fixup * hi_fixup;
assert (reloc_type == BFD_RELOC_M32R_HI16_SLO
|| reloc_type == BFD_RELOC_M32R_HI16_ULO);
hi_fixup = ((struct m32r_hi_fixup *)
xmalloc (sizeof (struct m32r_hi_fixup)));
hi_fixup->fixp = fixP;
hi_fixup->seg = now_seg;
hi_fixup->next = m32r_hi_fixup_list;
m32r_hi_fixup_list = hi_fixup;
}
/* Called while parsing an instruction to create a fixup.
We need to check for HI16 relocs and queue them up for later sorting. */
fixS *
m32r_cgen_record_fixup_exp (frag, where, insn, length, operand, opinfo, exp)
fragS * frag;
int where;
const CGEN_INSN * insn;
int length;
const CGEN_OPERAND * operand;
int opinfo;
expressionS * exp;
{
fixS * fixP = cgen_record_fixup_exp (frag, where, insn, length,
operand, opinfo, exp);
switch (CGEN_OPERAND_TYPE (operand))
{
case M32R_OPERAND_HI16 :
/* If low/high/shigh/sda was used, it is recorded in `opinfo'. */
if (fixP->tc_fix_data.opinfo == BFD_RELOC_M32R_HI16_SLO
|| fixP->tc_fix_data.opinfo == BFD_RELOC_M32R_HI16_ULO)
m32r_record_hi16 (fixP->tc_fix_data.opinfo, fixP, now_seg);
break;
}
return fixP;
}
/* Return BFD reloc type from opinfo field in a fixS.
It's tricky using fx_r_type in m32r_frob_file because the values
are BFD_RELOC_UNUSED + operand number. */
#define FX_OPINFO_R_TYPE(f) ((f)->tc_fix_data.opinfo)
/* Sort any unmatched HI16 relocs so that they immediately precede
the corresponding LO16 reloc. This is called before md_apply_fix and
tc_gen_reloc. */
void
m32r_frob_file ()
{
struct m32r_hi_fixup * l;
for (l = m32r_hi_fixup_list; l != NULL; l = l->next)
{
segment_info_type * seginfo;
int pass;
assert (FX_OPINFO_R_TYPE (l->fixp) == BFD_RELOC_M32R_HI16_SLO
|| FX_OPINFO_R_TYPE (l->fixp) == BFD_RELOC_M32R_HI16_ULO);
/* Check quickly whether the next fixup happens to be a matching low. */
if (l->fixp->fx_next != NULL
&& FX_OPINFO_R_TYPE (l->fixp->fx_next) == BFD_RELOC_M32R_LO16
&& l->fixp->fx_addsy == l->fixp->fx_next->fx_addsy
&& l->fixp->fx_offset == l->fixp->fx_next->fx_offset)
continue;
/* Look through the fixups for this segment for a matching `low'.
When we find one, move the high/shigh just in front of it. We do
this in two passes. In the first pass, we try to find a
unique `low'. In the second pass, we permit multiple high's
relocs for a single `low'. */
seginfo = seg_info (l->seg);
for (pass = 0; pass < 2; pass++)
{
fixS * f;
fixS * prev;
prev = NULL;
for (f = seginfo->fix_root; f != NULL; f = f->fx_next)
{
/* Check whether this is a `low' fixup which matches l->fixp. */
if (FX_OPINFO_R_TYPE (f) == BFD_RELOC_M32R_LO16
&& f->fx_addsy == l->fixp->fx_addsy
&& f->fx_offset == l->fixp->fx_offset
&& (pass == 1
|| prev == NULL
|| (FX_OPINFO_R_TYPE (prev) != BFD_RELOC_M32R_HI16_SLO
&& FX_OPINFO_R_TYPE (prev) != BFD_RELOC_M32R_HI16_ULO)
|| prev->fx_addsy != f->fx_addsy
|| prev->fx_offset != f->fx_offset))
{
fixS ** pf;
/* Move l->fixp before f. */
for (pf = &seginfo->fix_root;
* pf != l->fixp;
pf = & (* pf)->fx_next)
assert (* pf != NULL);
* pf = l->fixp->fx_next;
l->fixp->fx_next = f;
if (prev == NULL)
seginfo->fix_root = l->fixp;
else
prev->fx_next = l->fixp;
break;
}
prev = f;
}
if (f != NULL)
break;
if (pass == 1)
as_warn_where (l->fixp->fx_file, l->fixp->fx_line,
_("Unmatched high/shigh reloc"));
}
}
}
/* See whether we need to force a relocation into the output file.
This is used to force out switch and PC relative relocations when
relaxing. */
int
m32r_force_relocation (fix)
fixS * fix;
{
if (! m32r_relax)
return 0;
return (fix->fx_pcrel
|| 0 /* ??? */);
}
/* Write a value out to the object file, using the appropriate endianness. */
void
md_number_to_chars (buf, val, n)
char * buf;
valueT val;
int n;
{
if (target_big_endian)
number_to_chars_bigendian (buf, val, n);
else
number_to_chars_littleendian (buf, val, n);
}
/* Turn a string in input_line_pointer into a floating point constant of type
type, and store the appropriate bytes in *litP. The number of LITTLENUMS
emitted is stored in *sizeP . An error message is returned, or NULL on OK.
*/
/* Equal to MAX_PRECISION in atof-ieee.c */
#define MAX_LITTLENUMS 6
char *
md_atof (type, litP, sizeP)
char type;
char *litP;
int *sizeP;
{
int i;
int prec;
LITTLENUM_TYPE words [MAX_LITTLENUMS];
LITTLENUM_TYPE * wordP;
char * t;
char * atof_ieee ();
switch (type)
{
case 'f':
case 'F':
case 's':
case 'S':
prec = 2;
break;
case 'd':
case 'D':
case 'r':
case 'R':
prec = 4;
break;
/* FIXME: Some targets allow other format chars for bigger sizes here. */
default:
* sizeP = 0;
return _("Bad call to md_atof()");
}
t = atof_ieee (input_line_pointer, type, words);
if (t)
input_line_pointer = t;
* sizeP = prec * sizeof (LITTLENUM_TYPE);
if (target_big_endian)
{
for (i = 0; i < prec; i++)
{
md_number_to_chars (litP, (valueT) words[i],
sizeof (LITTLENUM_TYPE));
litP += sizeof (LITTLENUM_TYPE);
}
}
else
{
for (i = prec - 1; i >= 0; i--)
{
md_number_to_chars (litP, (valueT) words[i],
sizeof (LITTLENUM_TYPE));
litP += sizeof (LITTLENUM_TYPE);
}
}
return 0;
}
void
m32r_elf_section_change_hook ()
{
/* If we have reached the end of a section and we have just emitted a
16 bit insn, then emit a nop to make sure that the section ends on
a 32 bit boundary. */
if (prev_insn.insn || seen_relaxable_p)
(void) m32r_fill_insn (0);
}