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binutils-gdb/gas/config/tc-cris.c
Hans-Peter Nilsson 920e417765 Fix typo in comment in last commit
2001-11-17 18:51:15 +00:00

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/* tc-cris.c -- Assembler code for the CRIS CPU core.
Copyright 2000, 2001 Free Software Foundation, Inc.
Contributed by Axis Communications AB, Lund, Sweden.
Originally written for GAS 1.38.1 by Mikael Asker.
Updates, BFDizing, GNUifying and ELF support by Hans-Peter Nilsson.
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 "as.h"
#include "safe-ctype.h"
#include "subsegs.h"
#include "opcode/cris.h"
#include "dwarf2dbg.h"
/* Conventions used here:
Generally speaking, pointers to binutils types such as "fragS" and
"expressionS" get parameter and variable names ending in "P", such as
"fragP", to harmonize with the rest of the binutils code. Other
pointers get a "p" suffix, such as "bufp". Any function or type-name
that could clash with a current or future binutils or GAS function get
a "cris_" prefix. */
#define SYNTAX_RELAX_REG_PREFIX "no_register_prefix"
#define SYNTAX_ENFORCE_REG_PREFIX "register_prefix"
#define SYNTAX_USER_SYM_LEADING_UNDERSCORE "leading_underscore"
#define SYNTAX_USER_SYM_NO_LEADING_UNDERSCORE "no_leading_underscore"
#define REGISTER_PREFIX_CHAR '$'
/* Like in ":GOT", ":GOTOFF" etc. Other ports use '@', but that's in
line_separator_chars for CRIS, so we avoid it. */
#define PIC_SUFFIX_CHAR ':'
/* This might be CRIS_INSN_NONE if we're assembling a prefix-insn only.
Note that some prefix-insns might be assembled as CRIS_INSN_NORMAL. */
enum cris_insn_kind
{
CRIS_INSN_NORMAL, CRIS_INSN_NONE, CRIS_INSN_BRANCH
};
/* An instruction will have one of these prefixes.
Although the same bit-pattern, we handle BDAP with an immediate
expression (eventually quick or [pc+]) different from when we only have
register expressions. */
enum prefix_kind
{
PREFIX_NONE, PREFIX_BDAP_IMM, PREFIX_BDAP, PREFIX_BIAP, PREFIX_DIP,
PREFIX_PUSH
};
/* The prefix for an instruction. */
struct cris_prefix
{
enum prefix_kind kind;
int base_reg_number;
unsigned int opcode;
/* There might be an expression to be evaluated, like I in [rN+I]. */
expressionS expr;
/* If there's an expression, we might need a relocation. Here's the
type of what relocation to start relaxaton with.
The relocation is assumed to start immediately after the prefix insn,
so we don't provide an offset. */
enum bfd_reloc_code_real reloc;
};
/* The description of the instruction being assembled. */
struct cris_instruction
{
/* If CRIS_INSN_NONE, then this insn is of zero length. */
enum cris_insn_kind insn_type;
/* If a special register was mentioned, this is its description, else
it is NULL. */
const struct cris_spec_reg *spec_reg;
unsigned int opcode;
/* An insn may have at most one expression; theoretically there could be
another in its prefix (but I don't see how that could happen). */
expressionS expr;
/* The expression might need a relocation. Here's one to start
relaxation with. */
enum bfd_reloc_code_real reloc;
/* The size in bytes of an immediate expression, or zero if
nonapplicable. */
int imm_oprnd_size;
};
static void cris_process_instruction PARAMS ((char *,
struct cris_instruction *,
struct cris_prefix *));
static int get_bwd_size_modifier PARAMS ((char **, int *));
static int get_bw_size_modifier PARAMS ((char **, int *));
static int get_gen_reg PARAMS ((char **, int *));
static int get_spec_reg PARAMS ((char **,
const struct cris_spec_reg **));
static int get_autoinc_prefix_or_indir_op PARAMS ((char **,
struct cris_prefix *,
int *, int *, int *,
expressionS *));
static int get_3op_or_dip_prefix_op PARAMS ((char **,
struct cris_prefix *));
static int cris_get_expression PARAMS ((char **, expressionS *));
static int get_flags PARAMS ((char **, int *));
static void gen_bdap PARAMS ((int, expressionS *));
static int branch_disp PARAMS ((int));
static void gen_cond_branch_32 PARAMS ((char *, char *, fragS *,
symbolS *, symbolS *, long int));
static void cris_number_to_imm PARAMS ((char *, long, int, fixS *, segT));
static void cris_create_short_jump PARAMS ((char *, addressT, addressT,
fragS *, symbolS *));
static void s_syntax PARAMS ((int));
static void s_cris_file PARAMS ((int));
static void s_cris_loc PARAMS ((int));
/* Get ":GOT", ":GOTOFF", ":PLT" etc. suffixes. */
static void cris_get_pic_suffix PARAMS ((char **,
bfd_reloc_code_real_type *,
expressionS *));
static unsigned int cris_get_pic_reloc_size
PARAMS ((bfd_reloc_code_real_type));
/* All the .syntax functions. */
static void cris_force_reg_prefix PARAMS ((void));
static void cris_relax_reg_prefix PARAMS ((void));
static void cris_sym_leading_underscore PARAMS ((void));
static void cris_sym_no_leading_underscore PARAMS ((void));
static char *cris_insn_first_word_frag PARAMS ((void));
/* Handle to the opcode hash table. */
static struct hash_control *op_hash = NULL;
/* Whether we demand that registers have a `$' prefix. Default here. */
static boolean demand_register_prefix = false;
/* Whether global user symbols have a leading underscore. Default here. */
static boolean symbols_have_leading_underscore = true;
/* Whether or not we allow PIC, and expand to PIC-friendly constructs. */
static boolean pic = false;
const pseudo_typeS md_pseudo_table[] =
{
{"dword", cons, 4},
{"syntax", s_syntax, 0},
{"file", s_cris_file, 0},
{"loc", s_cris_loc, 0},
{NULL, 0, 0}
};
static int warn_for_branch_expansion = 0;
const char cris_comment_chars[] = ";";
/* This array holds the chars that only start a comment at the beginning of
a line. If the line seems to have the form '# 123 filename'
.line and .file directives will appear in the pre-processed output. */
/* Note that input_file.c hand-checks for '#' at the beginning of the
first line of the input file. This is because the compiler outputs
#NO_APP at the beginning of its output. */
/* Also note that slash-star will always start a comment. */
const char line_comment_chars[] = "#";
const char line_separator_chars[] = "@";
/* Now all floating point support is shut off. See md_atof. */
const char EXP_CHARS[] = "";
const char FLT_CHARS[] = "";
/* For CRIS, we encode the relax_substateTs (in e.g. fr_substate) as:
2 1 0
---/ /--+-----------------+-----------------+-----------------+
| what state ? | how long ? |
---/ /--+-----------------+-----------------+-----------------+
The "how long" bits are 00 = byte, 01 = word, 10 = dword (long).
This is a Un*x convention.
Not all lengths are legit for a given value of (what state).
Groups for CRIS address relaxing:
1. Bcc
length: byte, word, 10-byte expansion
2. BDAP
length: byte, word, dword */
#define STATE_CONDITIONAL_BRANCH (1)
#define STATE_BASE_PLUS_DISP_PREFIX (2)
#define STATE_LENGTH_MASK (3)
#define STATE_BYTE (0)
#define STATE_WORD (1)
#define STATE_DWORD (2)
/* Symbol undefined. */
#define STATE_UNDF (3)
#define STATE_MAX_LENGTH (3)
/* These displacements are relative to the adress following the opcode
word of the instruction. The first letter is Byte, Word. The 2nd
letter is Forward, Backward. */
#define BRANCH_BF ( 254)
#define BRANCH_BB (-256)
#define BRANCH_WF (2 + 32767)
#define BRANCH_WB (2 + -32768)
#define BDAP_BF ( 127)
#define BDAP_BB (-128)
#define BDAP_WF ( 32767)
#define BDAP_WB (-32768)
#define ENCODE_RELAX(what, length) (((what) << 2) + (length))
const relax_typeS md_cris_relax_table[] =
{
/* Error sentinel (0, 0). */
{1, 1, 0, 0},
/* Unused (0, 1). */
{1, 1, 0, 0},
/* Unused (0, 2). */
{1, 1, 0, 0},
/* Unused (0, 3). */
{1, 1, 0, 0},
/* Bcc o (1, 0). */
{BRANCH_BF, BRANCH_BB, 0, ENCODE_RELAX (1, 1)},
/* Bcc [PC+] (1, 1). */
{BRANCH_WF, BRANCH_WB, 2, ENCODE_RELAX (1, 2)},
/* BEXT/BWF, BA, JUMP (external), JUMP (always), Bnot_cc, JUMP (default)
(1, 2). */
{0, 0, 10, 0},
/* Unused (1, 3). */
{1, 1, 0, 0},
/* BDAP o (2, 0). */
{BDAP_BF, BDAP_BB, 0, ENCODE_RELAX (2, 1)},
/* BDAP.[bw] [PC+] (2, 1). */
{BDAP_WF, BDAP_WB, 2, ENCODE_RELAX (2, 2)},
/* BDAP.d [PC+] (2, 2). */
{0, 0, 4, 0}
};
#undef BRANCH_BF
#undef BRANCH_BB
#undef BRANCH_WF
#undef BRANCH_WB
#undef BDAP_BF
#undef BDAP_BB
#undef BDAP_WF
#undef BDAP_WB
/* Target-specific multicharacter options, not const-declared at usage
in 2.9.1 and CVS of 2000-02-16. */
struct option md_longopts[] =
{
#define OPTION_NO_US (OPTION_MD_BASE + 0)
{"no-underscore", no_argument, NULL, OPTION_NO_US},
#define OPTION_US (OPTION_MD_BASE + 1)
{"underscore", no_argument, NULL, OPTION_US},
#define OPTION_PIC (OPTION_MD_BASE + 2)
{"pic", no_argument, NULL, OPTION_PIC},
{NULL, no_argument, NULL, 0}
};
/* Not const-declared at usage in 2.9.1. */
size_t md_longopts_size = sizeof (md_longopts);
const char *md_shortopts = "hHN";
/* At first glance, this may seems wrong and should be 4 (ba + nop); but
since a short_jump must skip a *number* of long jumps, it must also be
a long jump. Here, we hope to make it a "ba [16bit_offs]" and a "nop"
for the delay slot and hope that the jump table at most needs
32767/4=8191 long-jumps. A branch is better than a jump, since it is
relative; we will not have a reloc to fix up somewhere.
Note that we can't add relocs, because relaxation uses these fixed
numbers, and md_create_short_jump is called after relaxation. */
const int md_short_jump_size = 6;
const int md_long_jump_size = 6;
/* Report output format. Small changes in output format (like elf
variants below) can happen until all options are parsed, but after
that, the output format must remain fixed. */
const char *
cris_target_format ()
{
switch (OUTPUT_FLAVOR)
{
case bfd_target_aout_flavour:
return "a.out-cris";
case bfd_target_elf_flavour:
if (symbols_have_leading_underscore)
return "elf32-us-cris";
return "elf32-cris";
default:
abort ();
return NULL;
}
}
/* Prepare machine-dependent frags for relaxation.
Called just before relaxation starts. Any symbol that is now undefined
will not become defined.
Return the correct fr_subtype in the frag.
Return the initial "guess for fr_var" to caller. 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 value. */
int
md_estimate_size_before_relax (fragP, segment_type)
fragS *fragP;
/* The segment is either N_DATA or N_TEXT. */
segT segment_type;
{
int old_fr_fix;
old_fr_fix = fragP->fr_fix;
switch (fragP->fr_subtype)
{
case ENCODE_RELAX (STATE_CONDITIONAL_BRANCH, STATE_UNDF):
if (S_GET_SEGMENT (fragP->fr_symbol) == segment_type)
/* The symbol lies in the same segment - a relaxable case. */
fragP->fr_subtype
= ENCODE_RELAX (STATE_CONDITIONAL_BRANCH, STATE_BYTE);
else
/* Unknown or not the same segment, so not relaxable. */
fragP->fr_subtype
= ENCODE_RELAX (STATE_CONDITIONAL_BRANCH, STATE_DWORD);
fragP->fr_var = md_cris_relax_table[fragP->fr_subtype].rlx_length;
break;
case ENCODE_RELAX (STATE_BASE_PLUS_DISP_PREFIX, STATE_UNDF):
/* Note that we can not do anything sane with relaxing
[rX + a_known_symbol_in_text], it will have to be a 32-bit
value.
We could play tricks with managing a constant pool and make
a_known_symbol_in_text a "bdap [pc + offset]" pointing there
(like the GOT for ELF shared libraries), but that's no use, it
would in general be no shorter or faster code, only more
complicated. */
if (S_GET_SEGMENT (fragP->fr_symbol) != absolute_section)
{
/* Go for dword if not absolute or same segment. */
fragP->fr_subtype
= ENCODE_RELAX (STATE_BASE_PLUS_DISP_PREFIX, STATE_DWORD);
fragP->fr_var = md_cris_relax_table[fragP->fr_subtype].rlx_length;
}
else
{
/* Absolute expression. */
long int value;
value = S_GET_VALUE (fragP->fr_symbol) + fragP->fr_offset;
if (value >= -128 && value <= 127)
{
/* Byte displacement. */
(fragP->fr_opcode)[0] = value;
}
else
{
/* Word or dword displacement. */
int pow2_of_size = 1;
char *writep;
if (value < -32768 || value > 32767)
{
/* Outside word range, make it a dword. */
pow2_of_size = 2;
}
/* Modify the byte-offset BDAP into a word or dword offset
BDAP. Or really, a BDAP rX,8bit into a
BDAP.[wd] rX,[PC+] followed by a word or dword. */
(fragP->fr_opcode)[0] = BDAP_PC_LOW + pow2_of_size * 16;
/* Keep the register number in the highest four bits. */
(fragP->fr_opcode)[1] &= 0xF0;
(fragP->fr_opcode)[1] |= BDAP_INCR_HIGH;
/* It grew by two or four bytes. */
fragP->fr_fix += 1 << pow2_of_size;
writep = fragP->fr_literal + old_fr_fix;
md_number_to_chars (writep, value, 1 << pow2_of_size);
}
frag_wane (fragP);
}
break;
case ENCODE_RELAX (STATE_CONDITIONAL_BRANCH, STATE_BYTE):
case ENCODE_RELAX (STATE_CONDITIONAL_BRANCH, STATE_WORD):
case ENCODE_RELAX (STATE_CONDITIONAL_BRANCH, STATE_DWORD):
case ENCODE_RELAX (STATE_BASE_PLUS_DISP_PREFIX, STATE_BYTE):
case ENCODE_RELAX (STATE_BASE_PLUS_DISP_PREFIX, STATE_WORD):
case ENCODE_RELAX (STATE_BASE_PLUS_DISP_PREFIX, STATE_DWORD):
/* When relaxing a section for the second time, we don't need to
do anything except making sure that fr_var is set right. */
fragP->fr_var = md_cris_relax_table[fragP->fr_subtype].rlx_length;
break;
default:
BAD_CASE (fragP->fr_subtype);
}
return fragP->fr_var + (fragP->fr_fix - old_fr_fix);
}
/* Perform post-processing of machine-dependent frags after relaxation.
Called after relaxation is finished.
In: Address of frag.
fr_type == rs_machine_dependent.
fr_subtype is what the address relaxed to.
Out: Any fixS:s and constants are set up.
The caller will turn the frag into a ".space 0". */
void
md_convert_frag (abfd, sec, fragP)
bfd *abfd ATTRIBUTE_UNUSED;
segT sec ATTRIBUTE_UNUSED;
fragS *fragP;
{
/* Pointer to first byte in variable-sized part of the frag. */
char *var_partp;
/* Pointer to first opcode byte in frag. */
char *opcodep;
/* Used to check integrity of the relaxation.
One of 2 = long, 1 = word, or 0 = byte. */
int length_code;
/* Size in bytes of variable-sized part of frag. */
int var_part_size = 0;
/* This is part of *fragP. It contains all information about addresses
and offsets to varying parts. */
symbolS *symbolP;
unsigned long var_part_offset;
/* Where, in file space, is _var of *fragP? */
unsigned long address_of_var_part = 0;
/* Where, in file space, does addr point? */
unsigned long target_address;
know (fragP->fr_type == rs_machine_dependent);
length_code = fragP->fr_subtype & STATE_LENGTH_MASK;
know (length_code >= 0 && length_code < STATE_MAX_LENGTH);
var_part_offset = fragP->fr_fix;
var_partp = fragP->fr_literal + var_part_offset;
opcodep = fragP->fr_opcode;
symbolP = fragP->fr_symbol;
target_address = (symbolP ? S_GET_VALUE (symbolP) : 0) + fragP->fr_offset;
address_of_var_part = fragP->fr_address + var_part_offset;
switch (fragP->fr_subtype)
{
case ENCODE_RELAX (STATE_CONDITIONAL_BRANCH, STATE_BYTE):
opcodep[0] = branch_disp ((target_address - address_of_var_part));
var_part_size = 0;
break;
case ENCODE_RELAX (STATE_CONDITIONAL_BRANCH, STATE_WORD):
/* We had a quick immediate branch, now turn it into a word one i.e. a
PC autoincrement. */
opcodep[0] = BRANCH_PC_LOW;
opcodep[1] &= 0xF0;
opcodep[1] |= BRANCH_INCR_HIGH;
md_number_to_chars (var_partp,
(long) (target_address - (address_of_var_part + 2)),
2);
var_part_size = 2;
break;
case ENCODE_RELAX (STATE_CONDITIONAL_BRANCH, STATE_DWORD):
gen_cond_branch_32 (fragP->fr_opcode, var_partp, fragP,
fragP->fr_symbol, (symbolS *) NULL,
fragP->fr_offset);
/* Ten bytes added: a branch, nop and a jump. */
var_part_size = 2 + 2 + 4 + 2;
break;
case ENCODE_RELAX (STATE_BASE_PLUS_DISP_PREFIX, STATE_BYTE):
var_partp[0] = target_address - (address_of_var_part + 1);
var_part_size = 0;
break;
case ENCODE_RELAX (STATE_BASE_PLUS_DISP_PREFIX, STATE_WORD):
/* We had a BDAP 8-bit "quick immediate", now turn it into a 16-bit
one that uses PC autoincrement. */
opcodep[0] = BDAP_PC_LOW + (1 << 4);
opcodep[1] &= 0xF0;
opcodep[1] |= BDAP_INCR_HIGH;
md_number_to_chars (var_partp, (long) (target_address), 2);
var_part_size = 2;
break;
case ENCODE_RELAX (STATE_BASE_PLUS_DISP_PREFIX, STATE_DWORD):
/* We had a BDAP 16-bit "word", change the offset to a dword. */
opcodep[0] = BDAP_PC_LOW + (2 << 4);
opcodep[1] &= 0xF0;
opcodep[1] |= BDAP_INCR_HIGH;
if (fragP->fr_symbol == NULL)
md_number_to_chars (var_partp, fragP->fr_offset, 4);
else
fix_new (fragP, var_partp - fragP->fr_literal, 4, fragP->fr_symbol,
fragP->fr_offset, 0, BFD_RELOC_32);
var_part_size = 4;
break;
default:
BAD_CASE (fragP->fr_subtype);
break;
}
fragP->fr_fix += var_part_size;
}
/* Generate a short jump around a secondary jump table.
Used by md_create_long_jump.
This used to be md_create_short_jump, but is now called from
md_create_long_jump instead, when sufficient.
since the sizes of the jumps are the same. It used to be brittle,
making possibilities for creating bad code. */
static void
cris_create_short_jump (storep, from_addr, to_addr, fragP, to_symbol)
char *storep;
addressT from_addr;
addressT to_addr;
fragS *fragP ATTRIBUTE_UNUSED;
symbolS *to_symbol ATTRIBUTE_UNUSED;
{
long int distance;
distance = to_addr - from_addr;
if (-254 <= distance && distance <= 256)
{
/* Create a "short" short jump: "BA distance - 2". */
storep[0] = branch_disp (distance - 2);
storep[1] = BA_QUICK_HIGH;
/* A nop for the delay slot. */
md_number_to_chars (storep + 2, NOP_OPCODE, 2);
/* The extra word should be filled with something sane too. Make it
a nop to keep disassembly sane. */
md_number_to_chars (storep + 4, NOP_OPCODE, 2);
}
else
{
/* Make it a "long" short jump: "BA (PC+)". */
md_number_to_chars (storep, BA_PC_INCR_OPCODE, 2);
/* ".WORD distance - 4". */
md_number_to_chars (storep + 2, (long) (distance - 4), 2);
/* A nop for the delay slot. */
md_number_to_chars (storep + 4, NOP_OPCODE, 2);
}
}
/* Generate a long jump in a secondary jump table.
storep Where to store the jump instruction.
from_addr Address of the jump instruction.
to_addr Destination address of the jump.
fragP Which frag the destination address operand
lies in.
to_symbol Destination symbol. */
void
md_create_long_jump (storep, from_addr, to_addr, fragP, to_symbol)
char *storep;
addressT from_addr;
addressT to_addr;
fragS *fragP;
symbolS *to_symbol;
{
long int distance;
distance = to_addr - from_addr;
if (-32763 <= distance && distance <= 32772)
{
/* Then make it a "short" long jump. */
cris_create_short_jump (storep, from_addr, to_addr, fragP,
to_symbol);
}
else
{
/* We have a "long" long jump: "JUMP [PC+]".
Make it an "ADD [PC+],PC" if we're supposed to emit PIC code. */
md_number_to_chars (storep,
pic ? ADD_PC_INCR_OPCODE : JUMP_PC_INCR_OPCODE, 2);
/* Follow with a ".DWORD to_addr", PC-relative for PIC. */
fix_new (fragP, storep + 2 - fragP->fr_literal, 4, to_symbol,
0, pic ? 1 : 0, pic ? BFD_RELOC_32_PCREL : BFD_RELOC_32);
}
}
/* Allocate space for the first piece of an insn, and mark it as the
start of the insn for debug-format use. */
static char *
cris_insn_first_word_frag ()
{
char *insnp = frag_more (2);
/* We need to mark the start of the insn by passing dwarf2_emit_insn
the offset from the current fragment position. This must be done
after the first fragment is created but before any other fragments
(fixed or varying) are created. Note that the offset only
corresponds to the "size" of the insn for a fixed-size,
non-expanded insn. */
if (OUTPUT_FLAVOR == bfd_target_elf_flavour)
dwarf2_emit_insn (2);
return insnp;
}
/* Port-specific assembler initialization. */
void
md_begin ()
{
const char *hashret = NULL;
int i = 0;
/* Set up a hash table for the instructions. */
op_hash = hash_new ();
if (op_hash == NULL)
as_fatal (_("Virtual memory exhausted"));
while (cris_opcodes[i].name != NULL)
{
const char *name = cris_opcodes[i].name;
hashret = hash_insert (op_hash, name, (PTR) &cris_opcodes[i]);
if (hashret != NULL && *hashret != '\0')
as_fatal (_("Can't hash `%s': %s\n"), cris_opcodes[i].name,
*hashret == 0 ? _("(unknown reason)") : hashret);
do
{
if (cris_opcodes[i].match & cris_opcodes[i].lose)
as_fatal (_("Buggy opcode: `%s' \"%s\"\n"), cris_opcodes[i].name,
cris_opcodes[i].args);
++i;
}
while (cris_opcodes[i].name != NULL
&& strcmp (cris_opcodes[i].name, name) == 0);
}
}
/* Assemble a source line. */
void
md_assemble (str)
char *str;
{
struct cris_instruction output_instruction;
struct cris_prefix prefix;
char *opcodep;
char *p;
know (str);
/* Do the low-level grunt - assemble to bits and split up into a prefix
and ordinary insn. */
cris_process_instruction (str, &output_instruction, &prefix);
/* Handle any prefixes to the instruction. */
switch (prefix.kind)
{
case PREFIX_NONE:
break;
/* When the expression is unknown for a BDAP, it can need 0, 2 or 4
extra bytes, so we handle it separately. */
case PREFIX_BDAP_IMM:
/* We only do it if the relocation is unspecified, i.e. not a PIC
relocation. */
if (prefix.reloc == BFD_RELOC_NONE)
{
gen_bdap (prefix.base_reg_number, &prefix.expr);
break;
}
/* Fall through. */
case PREFIX_BDAP:
case PREFIX_BIAP:
case PREFIX_DIP:
opcodep = cris_insn_first_word_frag ();
/* Output the prefix opcode. */
md_number_to_chars (opcodep, (long) prefix.opcode, 2);
/* Having a specified reloc only happens for DIP and for BDAP with
PIC operands, but it is ok to drop through here for the other
prefixes as they can have no relocs specified. */
if (prefix.reloc != BFD_RELOC_NONE)
{
unsigned int relocsize
= (prefix.kind == PREFIX_DIP
? 4 : cris_get_pic_reloc_size (prefix.reloc));
p = frag_more (relocsize);
fix_new_exp (frag_now, (p - frag_now->fr_literal), relocsize,
&prefix.expr, 0, prefix.reloc);
}
break;
case PREFIX_PUSH:
opcodep = cris_insn_first_word_frag ();
/* Output the prefix opcode. Being a "push", we add the negative
size of the register to "sp". */
if (output_instruction.spec_reg != NULL)
{
/* Special register. */
opcodep[0] = -output_instruction.spec_reg->reg_size;
}
else
{
/* General register. */
opcodep[0] = -4;
}
opcodep[1] = (REG_SP << 4) + (BDAP_QUICK_OPCODE >> 8);
break;
default:
BAD_CASE (prefix.kind);
}
/* If we only had a prefix insn, we're done. */
if (output_instruction.insn_type == CRIS_INSN_NONE)
return;
/* Done with the prefix. Continue with the main instruction. */
if (prefix.kind == PREFIX_NONE)
opcodep = cris_insn_first_word_frag ();
else
opcodep = frag_more (2);
/* Output the instruction opcode. */
md_number_to_chars (opcodep, (long) (output_instruction.opcode), 2);
/* Output the symbol-dependent instruction stuff. */
if (output_instruction.insn_type == CRIS_INSN_BRANCH)
{
segT to_seg = absolute_section;
int is_undefined = 0;
int length_code;
if (output_instruction.expr.X_op != O_constant)
{
to_seg = S_GET_SEGMENT (output_instruction.expr.X_add_symbol);
if (to_seg == undefined_section)
is_undefined = 1;
}
if (output_instruction.expr.X_op == O_constant
|| to_seg == now_seg || is_undefined)
{
/* Handle complex expressions. */
valueT addvalue
= (output_instruction.expr.X_op_symbol != NULL
? 0 : output_instruction.expr.X_add_number);
symbolS *sym
= (output_instruction.expr.X_op_symbol != NULL
? make_expr_symbol (&output_instruction.expr)
: output_instruction.expr.X_add_symbol);
/* If is_undefined, then the expression may BECOME now_seg. */
length_code = is_undefined ? STATE_UNDF : STATE_BYTE;
/* Make room for max ten bytes of variable length. */
frag_var (rs_machine_dependent, 10, 0,
ENCODE_RELAX (STATE_CONDITIONAL_BRANCH, length_code),
sym, addvalue, opcodep);
}
else
{
/* We have: to_seg != now_seg && to_seg != undefined_section.
This means it is a branch to a known symbol in another
section. Code in data? Weird but valid. Emit a 32-bit
branch. */
char *cond_jump = frag_more (10);
gen_cond_branch_32 (opcodep, cond_jump, frag_now,
output_instruction.expr.X_add_symbol,
(symbolS *) NULL,
output_instruction.expr.X_add_number);
}
}
else
{
if (output_instruction.imm_oprnd_size > 0)
{
/* The intruction has an immediate operand. */
enum bfd_reloc_code_real reloc = BFD_RELOC_NONE;
switch (output_instruction.imm_oprnd_size)
{
/* Any byte-size immediate constants are treated as
word-size. FIXME: Thus overflow check does not work
correctly. */
case 2:
/* Note that size-check for the explicit reloc has already
been done when we get here. */
if (output_instruction.reloc != BFD_RELOC_NONE)
reloc = output_instruction.reloc;
else
reloc = BFD_RELOC_16;
break;
case 4:
/* Allow a relocation specified in the operand. */
if (output_instruction.reloc != BFD_RELOC_NONE)
reloc = output_instruction.reloc;
else
reloc = BFD_RELOC_32;
break;
default:
BAD_CASE (output_instruction.imm_oprnd_size);
}
p = frag_more (output_instruction.imm_oprnd_size);
fix_new_exp (frag_now, (p - frag_now->fr_literal),
output_instruction.imm_oprnd_size,
&output_instruction.expr, 0, reloc);
}
else if (output_instruction.reloc != BFD_RELOC_NONE)
{
/* An immediate operand that has a relocation and needs to be
processed further. */
/* It is important to use fix_new_exp here and everywhere else
(and not fix_new), as fix_new_exp can handle "difference
expressions" - where the expression contains a difference of
two symbols in the same segment. */
fix_new_exp (frag_now, (opcodep - frag_now->fr_literal), 2,
&output_instruction.expr, 0,
output_instruction.reloc);
}
}
}
/* Low level text-to-bits assembly. */
static void
cris_process_instruction (insn_text, out_insnp, prefixp)
char *insn_text;
struct cris_instruction *out_insnp;
struct cris_prefix *prefixp;
{
char *s;
char modified_char = 0;
const char *args;
struct cris_opcode *instruction;
char *operands;
int match = 0;
int mode;
int regno;
int size_bits;
/* Reset these fields to a harmless state in case we need to return in
error. */
prefixp->kind = PREFIX_NONE;
prefixp->reloc = BFD_RELOC_NONE;
out_insnp->insn_type = CRIS_INSN_NORMAL;
out_insnp->imm_oprnd_size = 0;
/* Find the end of the opcode mnemonic. We assume (true in 2.9.1)
that the caller has translated the opcode to lower-case, up to the
first non-letter. */
for (operands = insn_text; ISLOWER (*operands); ++operands)
;
/* Terminate the opcode after letters, but save the character there if
it was of significance. */
switch (*operands)
{
case '\0':
break;
case '.':
/* Put back the modified character later. */
modified_char = *operands;
/* Fall through. */
case ' ':
/* Consume the character after the mnemonic
and replace it with '\0'. */
*operands++ = '\0';
break;
default:
as_bad (_("Unknown opcode: `%s'"), insn_text);
return;
}
/* Find the instruction. */
instruction = (struct cris_opcode *) hash_find (op_hash, insn_text);
if (instruction == NULL)
{
as_bad (_("Unknown opcode: `%s'"), insn_text);
return;
}
/* Put back the modified character. */
switch (modified_char)
{
case 0:
break;
default:
*--operands = modified_char;
}
/* Try to match an opcode table slot. */
for (s = operands;;)
{
int imm_expr_found;
/* Initialize *prefixp, perhaps after being modified for a
"near match". */
prefixp->kind = PREFIX_NONE;
prefixp->reloc = BFD_RELOC_NONE;
/* Initialize *out_insnp. */
memset (out_insnp, 0, sizeof (*out_insnp));
out_insnp->opcode = instruction->match;
out_insnp->reloc = BFD_RELOC_NONE;
out_insnp->insn_type = CRIS_INSN_NORMAL;
out_insnp->imm_oprnd_size = 0;
imm_expr_found = 0;
/* Build the opcode, checking as we go to make sure that the
operands match. */
for (args = instruction->args;; ++args)
{
switch (*args)
{
case '\0':
/* If we've come to the end of arguments, we're done. */
if (*s == '\0')
match = 1;
break;
case '!':
/* Non-matcher character for disassembly.
Ignore it here. */
continue;
case ',':
case ' ':
/* These must match exactly. */
if (*s++ == *args)
continue;
break;
case 'B':
/* This is not really an operand, but causes a "BDAP
-size,SP" prefix to be output, for PUSH instructions. */
prefixp->kind = PREFIX_PUSH;
continue;
case 'b':
/* This letter marks an operand that should not be matched
in the assembler. It is a branch with 16-bit
displacement. The assembler will create them from the
8-bit flavor when necessary. The assembler does not
support the [rN+] operand, as the [r15+] that is
generated for 16-bit displacements. */
break;
case 'c':
/* A 5-bit unsigned immediate in bits <4:0>. */
if (! cris_get_expression (&s, &out_insnp->expr))
break;
else
{
if (out_insnp->expr.X_op == O_constant
&& (out_insnp->expr.X_add_number < 0
|| out_insnp->expr.X_add_number > 31))
as_bad (_("Immediate value not in 5 bit unsigned range: %ld"),
out_insnp->expr.X_add_number);
out_insnp->reloc = BFD_RELOC_CRIS_UNSIGNED_5;
continue;
}
case 'C':
/* A 4-bit unsigned immediate in bits <3:0>. */
if (! cris_get_expression (&s, &out_insnp->expr))
break;
else
{
if (out_insnp->expr.X_op == O_constant
&& (out_insnp->expr.X_add_number < 0
|| out_insnp->expr.X_add_number > 15))
as_bad (_("Immediate value not in 4 bit unsigned range: %ld"),
out_insnp->expr.X_add_number);
out_insnp->reloc = BFD_RELOC_CRIS_UNSIGNED_4;
continue;
}
case 'D':
/* General register in bits <15:12> and <3:0>. */
if (! get_gen_reg (&s, &regno))
break;
else
{
out_insnp->opcode |= regno /* << 0 */;
out_insnp->opcode |= regno << 12;
continue;
}
case 'f':
/* Flags from the condition code register. */
{
int flags = 0;
if (! get_flags (&s, &flags))
break;
out_insnp->opcode |= ((flags & 0xf0) << 8) | (flags & 0xf);
continue;
}
case 'i':
/* A 6-bit signed immediate in bits <5:0>. */
if (! cris_get_expression (&s, &out_insnp->expr))
break;
else
{
if (out_insnp->expr.X_op == O_constant
&& (out_insnp->expr.X_add_number < -32
|| out_insnp->expr.X_add_number > 31))
as_bad (_("Immediate value not in 6 bit range: %ld"),
out_insnp->expr.X_add_number);
out_insnp->reloc = BFD_RELOC_CRIS_SIGNED_6;
continue;
}
case 'I':
/* A 6-bit unsigned immediate in bits <5:0>. */
if (! cris_get_expression (&s, &out_insnp->expr))
break;
else
{
if (out_insnp->expr.X_op == O_constant
&& (out_insnp->expr.X_add_number < 0
|| out_insnp->expr.X_add_number > 63))
as_bad (_("Immediate value not in 6 bit unsigned range: %ld"),
out_insnp->expr.X_add_number);
out_insnp->reloc = BFD_RELOC_CRIS_UNSIGNED_6;
continue;
}
case 'M':
/* A size modifier, B, W or D, to be put in a bit position
suitable for CLEAR instructions (i.e. reflecting a zero
register). */
if (! get_bwd_size_modifier (&s, &size_bits))
break;
else
{
switch (size_bits)
{
case 0:
out_insnp->opcode |= 0 << 12;
break;
case 1:
out_insnp->opcode |= 4 << 12;
break;
case 2:
out_insnp->opcode |= 8 << 12;
break;
}
continue;
}
case 'm':
/* A size modifier, B, W or D, to be put in bits <5:4>. */
if (! get_bwd_size_modifier (&s, &size_bits))
break;
else
{
out_insnp->opcode |= size_bits << 4;
continue;
}
case 'o':
/* A branch expression. */
if (! cris_get_expression (&s, &out_insnp->expr))
break;
else
{
out_insnp->insn_type = CRIS_INSN_BRANCH;
continue;
}
case 'O':
/* A BDAP expression for any size, "expr,r". */
if (! cris_get_expression (&s, &prefixp->expr))
break;
else
{
if (*s != ',')
break;
s++;
if (!get_gen_reg (&s, &prefixp->base_reg_number))
break;
/* Since 'O' is used with an explicit bdap, we have no
"real" instruction. */
prefixp->kind = PREFIX_BDAP_IMM;
prefixp->opcode
= BDAP_QUICK_OPCODE | (prefixp->base_reg_number << 12);
out_insnp->insn_type = CRIS_INSN_NONE;
continue;
}
case 'P':
/* Special register in bits <15:12>. */
if (! get_spec_reg (&s, &out_insnp->spec_reg))
break;
else
{
/* Use of some special register names come with a
specific warning. Note that we have no ".cpu type"
pseudo yet, so some of this is just unused
framework. */
if (out_insnp->spec_reg->warning)
as_warn (out_insnp->spec_reg->warning);
else if (out_insnp->spec_reg->applicable_version
== cris_ver_warning)
/* Others have a generic warning. */
as_warn (_("Unimplemented register `%s' specified"),
out_insnp->spec_reg->name);
out_insnp->opcode
|= out_insnp->spec_reg->number << 12;
continue;
}
case 'p':
/* This character is used in the disassembler to
recognize a prefix instruction to fold into the
addressing mode for the next instruction. It is
ignored here. */
continue;
case 'R':
/* General register in bits <15:12>. */
if (! get_gen_reg (&s, &regno))
break;
else
{
out_insnp->opcode |= regno << 12;
continue;
}
case 'r':
/* General register in bits <3:0>. */
if (! get_gen_reg (&s, &regno))
break;
else
{
out_insnp->opcode |= regno /* << 0 */;
continue;
}
case 'S':
/* Source operand in bit <10> and a prefix; a 3-operand
prefix. */
if (! get_3op_or_dip_prefix_op (&s, prefixp))
break;
else
continue;
case 's':
/* Source operand in bits <10>, <3:0> and optionally a
prefix; i.e. an indirect operand or an side-effect
prefix. */
if (! get_autoinc_prefix_or_indir_op (&s, prefixp, &mode,
&regno,
&imm_expr_found,
&out_insnp->expr))
break;
else
{
if (prefixp->kind != PREFIX_NONE)
{
/* A prefix, so it has the autoincrement bit
set. */
out_insnp->opcode |= (AUTOINCR_BIT << 8);
}
else
{
/* No prefix. The "mode" variable contains bits like
whether or not this is autoincrement mode. */
out_insnp->opcode |= (mode << 10);
/* If there was a PIC reloc specifier, then it was
attached to the prefix. Note that we can't check
that the reloc size matches, since we don't have
all the operands yet in all cases. */
if (prefixp->reloc != BFD_RELOC_NONE)
out_insnp->reloc = prefixp->reloc;
}
out_insnp->opcode |= regno /* << 0 */ ;
continue;
}
case 'x':
/* Rs.m in bits <15:12> and <5:4>. */
if (! get_gen_reg (&s, &regno)
|| ! get_bwd_size_modifier (&s, &size_bits))
break;
else
{
out_insnp->opcode |= (regno << 12) | (size_bits << 4);
continue;
}
case 'y':
/* Source operand in bits <10>, <3:0> and optionally a
prefix; i.e. an indirect operand or an side-effect
prefix.
The difference to 's' is that this does not allow an
"immediate" expression. */
if (! get_autoinc_prefix_or_indir_op (&s, prefixp,
&mode, &regno,
&imm_expr_found,
&out_insnp->expr)
|| imm_expr_found)
break;
else
{
if (prefixp->kind != PREFIX_NONE)
{
/* A prefix, and those matched here always have
side-effects (see 's' case). */
out_insnp->opcode |= (AUTOINCR_BIT << 8);
}
else
{
/* No prefix. The "mode" variable contains bits
like whether or not this is autoincrement
mode. */
out_insnp->opcode |= (mode << 10);
}
out_insnp->opcode |= regno /* << 0 */;
continue;
}
case 'z':
/* Size modifier (B or W) in bit <4>. */
if (! get_bw_size_modifier (&s, &size_bits))
break;
else
{
out_insnp->opcode |= size_bits << 4;
continue;
}
default:
BAD_CASE (*args);
}
/* We get here when we fail a match above or we found a
complete match. Break out of this loop. */
break;
}
/* Was it a match or a miss? */
if (match == 0)
{
/* If it's just that the args don't match, maybe the next
item in the table is the same opcode but with
matching operands. */
if (instruction[1].name != NULL
&& ! strcmp (instruction->name, instruction[1].name))
{
/* Yep. Restart and try that one instead. */
++instruction;
s = operands;
continue;
}
else
{
/* We've come to the end of instructions with this
opcode, so it must be an error. */
as_bad (_("Illegal operands"));
return;
}
}
else
{
/* We have a match. Check if there's anything more to do. */
if (imm_expr_found)
{
/* There was an immediate mode operand, so we must check
that it has an appropriate size. */
switch (instruction->imm_oprnd_size)
{
default:
case SIZE_NONE:
/* Shouldn't happen; this one does not have immediate
operands with different sizes. */
BAD_CASE (instruction->imm_oprnd_size);
break;
case SIZE_FIX_32:
out_insnp->imm_oprnd_size = 4;
break;
case SIZE_SPEC_REG:
switch (out_insnp->spec_reg->reg_size)
{
case 1:
if (out_insnp->expr.X_op == O_constant
&& (out_insnp->expr.X_add_number < -128
|| out_insnp->expr.X_add_number > 255))
as_bad (_("Immediate value not in 8 bit range: %ld"),
out_insnp->expr.X_add_number);
/* Fall through. */
case 2:
/* FIXME: We need an indicator in the instruction
table to pass on, to indicate if we need to check
overflow for a signed or unsigned number. */
if (out_insnp->expr.X_op == O_constant
&& (out_insnp->expr.X_add_number < -32768
|| out_insnp->expr.X_add_number > 65535))
as_bad (_("Immediate value not in 16 bit range: %ld"),
out_insnp->expr.X_add_number);
out_insnp->imm_oprnd_size = 2;
break;
case 4:
out_insnp->imm_oprnd_size = 4;
break;
default:
BAD_CASE (out_insnp->spec_reg->reg_size);
}
break;
case SIZE_FIELD:
switch (size_bits)
{
case 0:
if (out_insnp->expr.X_op == O_constant
&& (out_insnp->expr.X_add_number < -128
|| out_insnp->expr.X_add_number > 255))
as_bad (_("Immediate value not in 8 bit range: %ld"),
out_insnp->expr.X_add_number);
/* Fall through. */
case 1:
if (out_insnp->expr.X_op == O_constant
&& (out_insnp->expr.X_add_number < -32768
|| out_insnp->expr.X_add_number > 65535))
as_bad (_("Immediate value not in 16 bit range: %ld"),
out_insnp->expr.X_add_number);
out_insnp->imm_oprnd_size = 2;
break;
case 2:
out_insnp->imm_oprnd_size = 4;
break;
default:
BAD_CASE (out_insnp->spec_reg->reg_size);
}
}
/* If there was a relocation specified for the immediate
expression (i.e. it had a PIC modifier) check that the
size of the PIC relocation matches the size specified by
the opcode. */
if (out_insnp->reloc != BFD_RELOC_NONE
&& (cris_get_pic_reloc_size (out_insnp->reloc)
!= (unsigned int) out_insnp->imm_oprnd_size))
as_bad (_("PIC relocation size does not match operand size"));
}
}
break;
}
}
/* Get a B, W, or D size modifier from the string pointed out by *cPP,
which must point to a '.' in front of the modifier. On successful
return, *cPP is advanced to the character following the size
modifier, and is undefined otherwise.
cPP Pointer to pointer to string starting
with the size modifier.
size_bitsp Pointer to variable to contain the size bits on
successful return.
Return 1 iff a correct size modifier is found, else 0. */
static int
get_bwd_size_modifier (cPP, size_bitsp)
char **cPP;
int *size_bitsp;
{
if (**cPP != '.')
return 0;
else
{
/* Consume the '.'. */
(*cPP)++;
switch (**cPP)
{
case 'B':
case 'b':
*size_bitsp = 0;
break;
case 'W':
case 'w':
*size_bitsp = 1;
break;
case 'D':
case 'd':
*size_bitsp = 2;
break;
default:
return 0;
}
/* Consume the size letter. */
(*cPP)++;
return 1;
}
}
/* Get a B or W size modifier from the string pointed out by *cPP,
which must point to a '.' in front of the modifier. On successful
return, *cPP is advanced to the character following the size
modifier, and is undefined otherwise.
cPP Pointer to pointer to string starting
with the size modifier.
size_bitsp Pointer to variable to contain the size bits on
successful return.
Return 1 iff a correct size modifier is found, else 0. */
static int
get_bw_size_modifier (cPP, size_bitsp)
char **cPP;
int *size_bitsp;
{
if (**cPP != '.')
return 0;
else
{
/* Consume the '.'. */
(*cPP)++;
switch (**cPP)
{
case 'B':
case 'b':
*size_bitsp = 0;
break;
case 'W':
case 'w':
*size_bitsp = 1;
break;
default:
return 0;
}
/* Consume the size letter. */
(*cPP)++;
return 1;
}
}
/* Get a general register from the string pointed out by *cPP. The
variable *cPP is advanced to the character following the general
register name on a successful return, and has its initial position
otherwise.
cPP Pointer to pointer to string, beginning with a general
register name.
regnop Pointer to int containing the register number.
Return 1 iff a correct general register designator is found,
else 0. */
static int
get_gen_reg (cPP, regnop)
char **cPP;
int *regnop;
{
char *oldp;
oldp = *cPP;
/* Handle a sometimes-mandatory dollar sign as register prefix. */
if (**cPP == REGISTER_PREFIX_CHAR)
(*cPP)++;
else if (demand_register_prefix)
return 0;
switch (**cPP)
{
case 'P':
case 'p':
/* "P" as in "PC"? Consume the "P". */
(*cPP)++;
if ((**cPP == 'C' || **cPP == 'c')
&& ! ISALNUM ((*cPP)[1]))
{
/* It's "PC": consume the "c" and we're done. */
(*cPP)++;
*regnop = REG_PC;
return 1;
}
break;
case 'R':
case 'r':
/* Hopefully r[0-9] or r1[0-5]. Consume 'R' or 'r'. */
(*cPP)++;
if (ISDIGIT (**cPP))
{
/* It's r[0-9]. Consume and check the next digit. */
*regnop = **cPP - '0';
(*cPP)++;
if (! ISALNUM (**cPP))
{
/* No more digits, we're done. */
return 1;
}
else
{
/* One more digit. Consume and add. */
*regnop = *regnop * 10 + (**cPP - '0');
/* We need to check for a valid register number; Rn,
0 <= n <= MAX_REG. */
if (*regnop <= MAX_REG)
{
/* Consume second digit. */
(*cPP)++;
return 1;
}
}
}
break;
case 'S':
case 's':
/* "S" as in "SP"? Consume the "S". */
(*cPP)++;
if (**cPP == 'P' || **cPP == 'p')
{
/* It's "SP": consume the "p" and we're done. */
(*cPP)++;
*regnop = REG_SP;
return 1;
}
break;
default:
/* Just here to silence compilation warnings. */
;
}
/* We get here if we fail. Restore the pointer. */
*cPP = oldp;
return 0;
}
/* Get a special register from the string pointed out by *cPP. The
variable *cPP is advanced to the character following the special
register name if one is found, and retains its original position
otherwise.
cPP Pointer to pointer to string starting with a special register
name.
sregpp Pointer to Pointer to struct spec_reg, where a pointer to the
register description will be stored.
Return 1 iff a correct special register name is found. */
static int
get_spec_reg (cPP, sregpp)
char **cPP;
const struct cris_spec_reg **sregpp;
{
char *s1;
const char *s2;
char *name_begin = *cPP;
const struct cris_spec_reg *sregp;
/* Handle a sometimes-mandatory dollar sign as register prefix. */
if (*name_begin == REGISTER_PREFIX_CHAR)
name_begin++;
else if (demand_register_prefix)
return 0;
/* Loop over all special registers. */
for (sregp = cris_spec_regs; sregp->name != NULL; sregp++)
{
/* Start over from beginning of the supposed name. */
s1 = name_begin;
s2 = sregp->name;
while (*s2 != '\0' && TOLOWER (*s1) == *s2)
{
s1++;
s2++;
}
/* For a match, we must have consumed the name in the table, and we
must be outside what could be part of a name. Assume here that a
test for alphanumerics is sufficient for a name test. */
if (*s2 == 0 && ! ISALNUM (*s1))
{
/* We have a match. Update the pointer and be done. */
*cPP = s1;
*sregpp = sregp;
return 1;
}
}
/* If we got here, we did not find any name. */
return 0;
}
/* Get an unprefixed or side-effect-prefix operand from the string pointed
out by *cPP. The pointer *cPP is advanced to the character following
the indirect operand if we have success, else it contains an undefined
value.
cPP Pointer to pointer to string beginning with the first
character of the supposed operand.
prefixp Pointer to structure containing an optional instruction
prefix.
is_autoincp Pointer to int indicating the indirect or autoincrement
bits.
src_regnop Pointer to int containing the source register number in
the instruction.
imm_foundp Pointer to an int indicating if an immediate expression
is found.
imm_exprP Pointer to a structure containing an immediate
expression, if success and if *imm_foundp is nonzero.
Return 1 iff a correct indirect operand is found. */
static int
get_autoinc_prefix_or_indir_op (cPP, prefixp, is_autoincp, src_regnop,
imm_foundp, imm_exprP)
char **cPP;
struct cris_prefix *prefixp;
int *is_autoincp;
int *src_regnop;
int *imm_foundp;
expressionS *imm_exprP;
{
/* Assume there was no immediate mode expression. */
*imm_foundp = 0;
if (**cPP == '[')
{
/* So this operand is one of:
Indirect: [rN]
Autoincrement: [rN+]
Indexed with assign: [rN=rM+rO.S]
Offset with assign: [rN=rM+I], [rN=rM+[rO].s], [rN=rM+[rO+].s]
Either way, consume the '['. */
(*cPP)++;
/* Get the rN register. */
if (! get_gen_reg (cPP, src_regnop))
/* If there was no register, then this cannot match. */
return 0;
else
{
/* We got the register, now check the next character. */
switch (**cPP)
{
case ']':
/* Indirect mode. We're done here. */
prefixp->kind = PREFIX_NONE;
*is_autoincp = 0;
break;
case '+':
/* This must be an auto-increment mode, if there's a
match. */
prefixp->kind = PREFIX_NONE;
*is_autoincp = 1;
/* We consume this character and break out to check the
closing ']'. */
(*cPP)++;
break;
case '=':
/* This must be indexed with assign, or offset with assign
to match. */
(*cPP)++;
/* Either way, the next thing must be a register. */
if (! get_gen_reg (cPP, &prefixp->base_reg_number))
/* No register, no match. */
return 0;
else
{
/* We've consumed "[rN=rM", so we must be looking at
"+rO.s]" or "+I]", or "-I]", or "+[rO].s]" or
"+[rO+].s]". */
if (**cPP == '+')
{
int index_reg_number;
(*cPP)++;
if (**cPP == '[')
{
int size_bits;
/* This must be [rx=ry+[rz].s] or
[rx=ry+[rz+].s] or no match. We must be
looking at rz after consuming the '['. */
(*cPP)++;
if (!get_gen_reg (cPP, &index_reg_number))
return 0;
prefixp->kind = PREFIX_BDAP;
prefixp->opcode
= (BDAP_INDIR_OPCODE
+ (prefixp->base_reg_number << 12)
+ index_reg_number);
if (**cPP == '+')
{
/* We've seen "[rx=ry+[rz+" here, so now we
know that there must be "].s]" left to
check. */
(*cPP)++;
prefixp->opcode |= AUTOINCR_BIT << 8;
}
/* If it wasn't autoincrement, we don't need to
add anything. */
/* Check the next-to-last ']'. */
if (**cPP != ']')
return 0;
(*cPP)++;
/* Check the ".s" modifier. */
if (! get_bwd_size_modifier (cPP, &size_bits))
return 0;
prefixp->opcode |= size_bits << 4;
/* Now we got [rx=ry+[rz+].s or [rx=ry+[rz].s.
We break out to check the final ']'. */
break;
}
/* It wasn't an indirection. Check if it's a
register. */
else if (get_gen_reg (cPP, &index_reg_number))
{
int size_bits;
/* Indexed with assign mode: "[rN+rM.S]". */
prefixp->kind = PREFIX_BIAP;
prefixp->opcode
= (BIAP_OPCODE + (index_reg_number << 12)
+ prefixp->base_reg_number /* << 0 */);
if (! get_bwd_size_modifier (cPP, &size_bits))
/* Size missing, this isn't a match. */
return 0;
else
{
/* Size found, break out to check the
final ']'. */
prefixp->opcode |= size_bits << 4;
break;
}
}
/* Not a register. Then this must be "[rN+I]". */
else if (cris_get_expression (cPP, &prefixp->expr))
{
/* We've got offset with assign mode. Fill
in the blanks and break out to match the
final ']'. */
prefixp->kind = PREFIX_BDAP_IMM;
/* We tentatively put an opcode corresponding to
a 32-bit operand here, although it may be
relaxed when there's no PIC specifier for the
operand. */
prefixp->opcode
= (BDAP_INDIR_OPCODE
| (prefixp->base_reg_number << 12)
| (AUTOINCR_BIT << 8)
| (2 << 4)
| REG_PC /* << 0 */);
/* This can have a PIC suffix, specifying reloc
type to use. */
if (pic && **cPP == PIC_SUFFIX_CHAR)
{
unsigned int relocsize;
cris_get_pic_suffix (cPP, &prefixp->reloc,
&prefixp->expr);
/* Tweak the size of the immediate operand
in the prefix opcode if it isn't what we
set. */
relocsize
= cris_get_pic_reloc_size (prefixp->reloc);
if (relocsize != 4)
prefixp->opcode
= ((prefixp->opcode & ~(3 << 4))
| ((relocsize >> 1) << 4));
}
break;
}
else
/* Neither register nor expression found, so
this can't be a match. */
return 0;
}
/* Not "[rN+" but perhaps "[rN-"? */
else if (**cPP == '-')
{
/* We must have an offset with assign mode. */
if (! cris_get_expression (cPP, &prefixp->expr))
/* No expression, no match. */
return 0;
else
{
/* We've got offset with assign mode. Fill
in the blanks and break out to match the
final ']'.
Note that we don't allow a PIC suffix for an
operand with a minus sign. */
prefixp->kind = PREFIX_BDAP_IMM;
break;
}
}
else
/* Neither '+' nor '-' after "[rN=rM". Lose. */
return 0;
}
default:
/* Neither ']' nor '+' nor '=' after "[rN". Lose. */
return 0;
}
}
/* When we get here, we have a match and will just check the closing
']'. We can still fail though. */
if (**cPP != ']')
return 0;
else
{
/* Don't forget to consume the final ']'.
Then return in glory. */
(*cPP)++;
return 1;
}
}
/* No indirection. Perhaps a constant? */
else if (cris_get_expression (cPP, imm_exprP))
{
/* Expression found, this is immediate mode. */
prefixp->kind = PREFIX_NONE;
*is_autoincp = 1;
*src_regnop = REG_PC;
*imm_foundp = 1;
/* This can have a PIC suffix, specifying reloc type to use. The
caller must check that the reloc size matches the operand size. */
if (pic && **cPP == PIC_SUFFIX_CHAR)
cris_get_pic_suffix (cPP, &prefixp->reloc, imm_exprP);
return 1;
}
/* No luck today. */
return 0;
}
/* This function gets an indirect operand in a three-address operand
combination from the string pointed out by *cPP. The pointer *cPP is
advanced to the character following the indirect operand on success, or
has an unspecified value on failure.
cPP Pointer to pointer to string begining
with the operand
prefixp Pointer to structure containing an
instruction prefix
Returns 1 iff a correct indirect operand is found. */
static int
get_3op_or_dip_prefix_op (cPP, prefixp)
char **cPP;
struct cris_prefix *prefixp;
{
int reg_number;
if (**cPP != '[')
/* We must have a '[' or it's a clean failure. */
return 0;
/* Eat the first '['. */
(*cPP)++;
if (**cPP == '[')
{
/* A second '[', so this must be double-indirect mode. */
(*cPP)++;
prefixp->kind = PREFIX_DIP;
prefixp->opcode = DIP_OPCODE;
/* Get the register or fail entirely. */
if (! get_gen_reg (cPP, &reg_number))
return 0;
else
{
prefixp->opcode |= reg_number /* << 0 */ ;
if (**cPP == '+')
{
/* Since we found a '+', this must be double-indirect
autoincrement mode. */
(*cPP)++;
prefixp->opcode |= AUTOINCR_BIT << 8;
}
/* There's nothing particular to do, if this was a
double-indirect *without* autoincrement. */
}
/* Check the first ']'. The second one is checked at the end. */
if (**cPP != ']')
return 0;
/* Eat the first ']', so we'll be looking at a second ']'. */
(*cPP)++;
}
/* No second '['. Then we should have a register here, making
it "[rN". */
else if (get_gen_reg (cPP, &prefixp->base_reg_number))
{
/* This must be indexed or offset mode: "[rN+I]" or
"[rN+rM.S]" or "[rN+[rM].S]" or "[rN+[rM+].S]". */
if (**cPP == '+')
{
int index_reg_number;
(*cPP)++;
if (**cPP == '[')
{
/* This is "[rx+["... Expect a register next. */
int size_bits;
(*cPP)++;
if (!get_gen_reg (cPP, &index_reg_number))
return 0;
prefixp->kind = PREFIX_BDAP;
prefixp->opcode
= (BDAP_INDIR_OPCODE
+ (prefixp->base_reg_number << 12)
+ index_reg_number);
/* We've seen "[rx+[ry", so check if this is
autoincrement. */
if (**cPP == '+')
{
/* Yep, now at "[rx+[ry+". */
(*cPP)++;
prefixp->opcode |= AUTOINCR_BIT << 8;
}
/* If it wasn't autoincrement, we don't need to
add anything. */
/* Check a first closing ']': "[rx+[ry]" or
"[rx+[ry+]". */
if (**cPP != ']')
return 0;
(*cPP)++;
/* Now expect a size modifier ".S". */
if (! get_bwd_size_modifier (cPP, &size_bits))
return 0;
prefixp->opcode |= size_bits << 4;
/* Ok, all interesting stuff has been seen:
"[rx+[ry+].S" or "[rx+[ry].S". We only need to
expect a final ']', which we'll do in a common
closing session. */
}
/* Seen "[rN+", but not a '[', so check if we have a
register. */
else if (get_gen_reg (cPP, &index_reg_number))
{
/* This is indexed mode: "[rN+rM.S]" or
"[rN+rM.S+]". */
int size_bits;
prefixp->kind = PREFIX_BIAP;
prefixp->opcode
= (BIAP_OPCODE
| prefixp->base_reg_number /* << 0 */
| (index_reg_number << 12));
/* Consume the ".S". */
if (! get_bwd_size_modifier (cPP, &size_bits))
/* Missing size, so fail. */
return 0;
else
/* Size found. Add that piece and drop down to
the common checking of the closing ']'. */
prefixp->opcode |= size_bits << 4;
}
/* Seen "[rN+", but not a '[' or a register, so then
it must be a constant "I". */
else if (cris_get_expression (cPP, &prefixp->expr))
{
/* Expression found, so fill in the bits of offset
mode and drop down to check the closing ']'. */
prefixp->kind = PREFIX_BDAP_IMM;
/* We tentatively put an opcode corresponding to a 32-bit
operand here, although it may be relaxed when there's no
PIC specifier for the operand. */
prefixp->opcode
= (BDAP_INDIR_OPCODE
| (prefixp->base_reg_number << 12)
| (AUTOINCR_BIT << 8)
| (2 << 4)
| REG_PC /* << 0 */);
/* This can have a PIC suffix, specifying reloc type to use. */
if (pic && **cPP == PIC_SUFFIX_CHAR)
{
unsigned int relocsize;
cris_get_pic_suffix (cPP, &prefixp->reloc, &prefixp->expr);
/* Tweak the size of the immediate operand in the prefix
opcode if it isn't what we set. */
relocsize = cris_get_pic_reloc_size (prefixp->reloc);
if (relocsize != 4)
prefixp->opcode
= ((prefixp->opcode & ~(3 << 4))
| ((relocsize >> 1) << 4));
}
}
else
/* Nothing valid here: lose. */
return 0;
}
/* Seen "[rN" but no '+', so check if it's a '-'. */
else if (**cPP == '-')
{
/* Yep, we must have offset mode. */
if (! cris_get_expression (cPP, &prefixp->expr))
/* No expression, so we lose. */
return 0;
else
{
/* Expression found to make this offset mode, so
fill those bits and drop down to check the
closing ']'.
Note that we don't allow a PIC suffix for
an operand with a minus sign like this. */
prefixp->kind = PREFIX_BDAP_IMM;
}
}
else
{
/* We've seen "[rN", but not '+' or '-'; rather a ']'.
Hmm. Normally this is a simple indirect mode that we
shouldn't match, but if we expect ']', then we have a
zero offset, so it can be a three-address-operand,
like "[rN],rO,rP", thus offset mode.
Don't eat the ']', that will be done in the closing
ceremony. */
prefixp->expr.X_op = O_constant;
prefixp->expr.X_add_number = 0;
prefixp->expr.X_add_symbol = NULL;
prefixp->expr.X_op_symbol = NULL;
prefixp->kind = PREFIX_BDAP_IMM;
}
}
/* A '[', but no second '[', and no register. Check if we
have an expression, making this "[I]" for a double-indirect
prefix. */
else if (cris_get_expression (cPP, &prefixp->expr))
{
/* Expression found, the so called absolute mode for a
double-indirect prefix on PC. */
prefixp->kind = PREFIX_DIP;
prefixp->opcode = DIP_OPCODE | (AUTOINCR_BIT << 8) | REG_PC;
prefixp->reloc = BFD_RELOC_32;
}
else
/* Neither '[' nor register nor expression. We lose. */
return 0;
/* We get here as a closing ceremony to a successful match. We just
need to check the closing ']'. */
if (**cPP != ']')
/* Oops. Close but no air-polluter. */
return 0;
/* Don't forget to consume that ']', before returning in glory. */
(*cPP)++;
return 1;
}
/* Get an expression from the string pointed out by *cPP.
The pointer *cPP is advanced to the character following the expression
on a success, or retains its original value otherwise.
cPP Pointer to pointer to string beginning with the expression.
exprP Pointer to structure containing the expression.
Return 1 iff a correct expression is found. */
static int
cris_get_expression (cPP, exprP)
char **cPP;
expressionS *exprP;
{
char *saved_input_line_pointer;
segT exp;
/* The "expression" function expects to find an expression at the
global variable input_line_pointer, so we have to save it to give
the impression that we don't fiddle with global variables. */
saved_input_line_pointer = input_line_pointer;
input_line_pointer = *cPP;
exp = expression (exprP);
if (exprP->X_op == O_illegal || exprP->X_op == O_absent)
{
input_line_pointer = saved_input_line_pointer;
return 0;
}
/* Everything seems to be fine, just restore the global
input_line_pointer and say we're successful. */
*cPP = input_line_pointer;
input_line_pointer = saved_input_line_pointer;
return 1;
}
/* Get a sequence of flag characters from *spp. The pointer *cPP is
advanced to the character following the expression. The flag
characters are consecutive, no commas or spaces.
cPP Pointer to pointer to string beginning with the expression.
flagp Pointer to int to return the flags expression.
Return 1 iff a correct flags expression is found. */
static int
get_flags (cPP, flagsp)
char **cPP;
int *flagsp;
{
for (;;)
{
switch (**cPP)
{
case 'd':
case 'D':
case 'm':
case 'M':
*flagsp |= 0x80;
break;
case 'e':
case 'E':
case 'b':
case 'B':
*flagsp |= 0x40;
break;
case 'i':
case 'I':
*flagsp |= 0x20;
break;
case 'x':
case 'X':
*flagsp |= 0x10;
break;
case 'n':
case 'N':
*flagsp |= 0x8;
break;
case 'z':
case 'Z':
*flagsp |= 0x4;
break;
case 'v':
case 'V':
*flagsp |= 0x2;
break;
case 'c':
case 'C':
*flagsp |= 1;
break;
default:
/* We consider this successful if we stop at a comma or
whitespace. Anything else, and we consider it a failure. */
if (**cPP != ','
&& **cPP != 0
&& ! ISSPACE (**cPP))
return 0;
else
return 1;
}
/* Don't forget to consume each flag character. */
(*cPP)++;
}
}
/* Generate code and fixes for a BDAP prefix.
base_regno Int containing the base register number.
exprP Pointer to structure containing the offset expression. */
static void
gen_bdap (base_regno, exprP)
int base_regno;
expressionS *exprP;
{
unsigned int opcode;
char *opcodep;
/* Put out the prefix opcode; assume quick immediate mode at first. */
opcode = BDAP_QUICK_OPCODE | (base_regno << 12);
opcodep = cris_insn_first_word_frag ();
md_number_to_chars (opcodep, opcode, 2);
if (exprP->X_op == O_constant)
{
/* We have an absolute expression that we know the size of right
now. */
long int value;
int size;
value = exprP->X_add_number;
if (value < -32768 || value > 32767)
/* Outside range for a "word", make it a dword. */
size = 2;
else
/* Assume "word" size. */
size = 1;
/* If this is a signed-byte value, we can fit it into the prefix
insn itself. */
if (value >= -128 && value <= 127)
opcodep[0] = value;
else
{
/* This is a word or dword displacement, which will be put in a
word or dword after the prefix. */
char *p;
opcodep[0] = BDAP_PC_LOW + (size << 4);
opcodep[1] &= 0xF0;
opcodep[1] |= BDAP_INCR_HIGH;
p = frag_more (1 << size);
md_number_to_chars (p, value, 1 << size);
}
}
else
{
/* Handle complex expressions. */
valueT addvalue
= exprP->X_op_symbol != NULL ? 0 : exprP->X_add_number;
symbolS *sym
= (exprP->X_op_symbol != NULL
? make_expr_symbol (exprP) : exprP->X_add_symbol);
/* The expression is not defined yet but may become absolute. We
make it a relocation to be relaxed. */
frag_var (rs_machine_dependent, 4, 0,
ENCODE_RELAX (STATE_BASE_PLUS_DISP_PREFIX, STATE_UNDF),
sym, addvalue, opcodep);
}
}
/* Encode a branch displacement in the range -256..254 into the form used
by CRIS conditional branch instructions.
offset The displacement value in bytes. */
static int
branch_disp (offset)
int offset;
{
int disp;
disp = offset & 0xFE;
if (offset < 0)
disp |= 1;
return disp;
}
/* Generate code and fixes for a 32-bit conditional branch instruction
created by "extending" an existing 8-bit branch instruction.
opcodep Pointer to the word containing the original 8-bit branch
instruction.
writep Pointer to "extension area" following the first instruction
word.
fragP Pointer to the frag containing the instruction.
add_symP, Parts of the destination address expression.
sub_symP,
add_num. */
static void
gen_cond_branch_32 (opcodep, writep, fragP, add_symP, sub_symP, add_num)
char *opcodep;
char *writep;
fragS *fragP;
symbolS *add_symP;
symbolS *sub_symP;
long int add_num;
{
if (warn_for_branch_expansion)
as_warn_where (fragP->fr_file, fragP->fr_line,
_("32-bit conditional branch generated"));
/* Here, writep points to what will be opcodep + 2. First, we change
the actual branch in opcodep[0] and opcodep[1], so that in the
final insn, it will look like:
opcodep+10: Bcc .-6
This means we don't have to worry about changing the opcode or
messing with the delay-slot instruction. So, we move it to last in
the "extended" branch, and just change the displacement. Admittedly,
it's not the optimal extended construct, but we should get this
rarely enough that it shouldn't matter. */
writep[8] = branch_disp (-2 - 6);
writep[9] = opcodep[1];
/* Then, we change the branch to an unconditional branch over the
extended part, to the new location of the Bcc:
opcodep: BA .+10
opcodep+2: NOP
Note that these two writes are to currently different locations,
merged later. */
md_number_to_chars (opcodep, BA_QUICK_OPCODE + 8, 2);
md_number_to_chars (writep, NOP_OPCODE, 2);
/* Then the extended thing, the 32-bit jump insn.
opcodep+4: JUMP [PC+]
or, in the PIC case,
opcodep+4: ADD [PC+],PC. */
md_number_to_chars (writep + 2,
pic ? ADD_PC_INCR_OPCODE : JUMP_PC_INCR_OPCODE, 2);
/* We have to fill in the actual value too.
opcodep+6: .DWORD
This is most probably an expression, but we can cope with an absolute
value too. FIXME: Testcase needed with and without pic. */
if (add_symP == NULL && sub_symP == NULL)
{
/* An absolute address. */
if (pic)
fix_new (fragP, writep + 4 - fragP->fr_literal, 4,
section_symbol (absolute_section),
add_num, 1, BFD_RELOC_32_PCREL);
else
md_number_to_chars (writep + 4, add_num, 4);
}
else
{
if (sub_symP != NULL)
as_bad_where (fragP->fr_file, fragP->fr_line,
_("Complex expression not supported"));
/* Not absolute, we have to make it a frag for later evaluation. */
fix_new (fragP, writep + 4 - fragP->fr_literal, 4, add_symP,
add_num, pic ? 1 : 0, pic ? BFD_RELOC_32_PCREL : BFD_RELOC_32);
}
}
/* Get the size of an immediate-reloc in bytes. Only valid for PIC
relocs. */
static unsigned int
cris_get_pic_reloc_size (reloc)
bfd_reloc_code_real_type reloc;
{
return reloc == BFD_RELOC_CRIS_16_GOTPLT || reloc == BFD_RELOC_CRIS_16_GOT
? 2 : 4;
}
/* Store a reloc type at *RELOCP corresponding to the PIC suffix at *CPP.
Adjust *EXPRP with any addend found after the PIC suffix. */
static void
cris_get_pic_suffix (cPP, relocp, exprP)
char **cPP;
bfd_reloc_code_real_type *relocp;
expressionS *exprP;
{
char *s = *cPP;
unsigned int i;
expressionS const_expr;
const struct pic_suffixes_struct
{
const char *const suffix;
unsigned int len;
bfd_reloc_code_real_type reloc;
} pic_suffixes[] =
{
#undef PICMAP
#define PICMAP(s, r) {s, sizeof (s) - 1, r}
/* Keep this in order with longest unambiguous prefix first. */
PICMAP ("GOTPLT16", BFD_RELOC_CRIS_16_GOTPLT),
PICMAP ("GOTPLT", BFD_RELOC_CRIS_32_GOTPLT),
PICMAP ("PLTG", BFD_RELOC_CRIS_32_PLT_GOTREL),
PICMAP ("PLT", BFD_RELOC_CRIS_32_PLT_PCREL),
PICMAP ("GOTOFF", BFD_RELOC_CRIS_32_GOTREL),
PICMAP ("GOT16", BFD_RELOC_CRIS_16_GOT),
PICMAP ("GOT", BFD_RELOC_CRIS_32_GOT)
};
/* We've already seen the ':', so consume it. */
s++;
for (i = 0; i < sizeof (pic_suffixes)/sizeof (pic_suffixes[0]); i++)
{
if (strncmp (s, pic_suffixes[i].suffix, pic_suffixes[i].len) == 0
&& ! is_part_of_name (s[pic_suffixes[i].len]))
{
/* We have a match. Consume the suffix and set the relocation
type. */
s += pic_suffixes[i].len;
/* There can be a constant term appended. If so, we will add it
to *EXPRP. */
if (*s == '+' || *s == '-')
{
if (! cris_get_expression (&s, &const_expr))
/* There was some kind of syntax error. Bail out. */
break;
/* Allow complex expressions as the constant part. It still
has to be an assembly-time constant or there will be an
error emitting the reloc. This makes the PIC qualifiers
idempotent; foo:GOTOFF+32 == foo+32:GOTOFF. The former we
recognize here; the latter is parsed in the incoming
expression. */
exprP->X_add_symbol = make_expr_symbol (exprP);
exprP->X_op = O_add;
exprP->X_add_number = 0;
exprP->X_op_symbol = make_expr_symbol (&const_expr);
}
*relocp = pic_suffixes[i].reloc;
*cPP = s;
return;
}
}
/* No match. Don't consume anything; fall back and there will be a
syntax error. */
}
/* This *could* be:
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.
type A character from FLTCHARS that describes what kind of
floating-point number is wanted.
litp A pointer to an array that the result should be stored in.
sizep A pointer to an integer where the size of the result is stored.
But we don't support floating point constants in assembly code *at all*,
since it's suboptimal and just opens up bug opportunities. GCC emits
the bit patterns as hex. All we could do here is to emit what GCC
would have done in the first place. *Nobody* writes floating-point
code as assembly code, but if they do, they should be able enough to
find out the correct bit patterns and use them. */
char *
md_atof (type, litp, sizep)
char type ATTRIBUTE_UNUSED;
char *litp ATTRIBUTE_UNUSED;
int *sizep ATTRIBUTE_UNUSED;
{
/* FIXME: Is this function mentioned in the internals.texi manual? If
not, add it. */
return _("Bad call to md_atof () - floating point formats are not supported");
}
/* Turn a number as a fixS * into a series of bytes that represents the
number on the target machine. The purpose of this procedure is the
same as that of md_number_to_chars but this procedure is supposed to
handle general bit field fixes and machine-dependent fixups.
bufp Pointer to an array where the result should be stored.
val The value to store.
n The number of bytes in "val" that should be stored.
fixP The fix to be applied to the bit field starting at bufp.
seg The segment containing this number. */
static void
cris_number_to_imm (bufp, val, n, fixP, seg)
char *bufp;
long val;
int n;
fixS *fixP;
segT seg;
{
segT sym_seg;
know (n <= 4);
know (fixP);
/* We put the relative "vma" for the other segment for inter-segment
relocations in the object data to stay binary "compatible" (with an
uninteresting old version) for the relocation.
Maybe delete some day. */
if (fixP->fx_addsy
&& (sym_seg = S_GET_SEGMENT (fixP->fx_addsy)) != seg)
val += sym_seg->vma;
if (fixP->fx_addsy != NULL || fixP->fx_pcrel)
switch (fixP->fx_r_type)
{
/* These must be fully resolved when getting here. */
case BFD_RELOC_32_PCREL:
case BFD_RELOC_16_PCREL:
case BFD_RELOC_8_PCREL:
as_bad_where (fixP->fx_frag->fr_file, fixP->fx_frag->fr_line,
_("PC-relative relocation must be trivially resolved"));
default:
;
}
switch (fixP->fx_r_type)
{
/* Ditto here, we put the addend into the object code as
well as the reloc addend. Keep it that way for now, to simplify
regression tests on the object file contents. FIXME: Seems
uninteresting now that we have a test suite. */
case BFD_RELOC_CRIS_16_GOT:
case BFD_RELOC_CRIS_32_GOT:
case BFD_RELOC_CRIS_32_GOTREL:
case BFD_RELOC_CRIS_16_GOTPLT:
case BFD_RELOC_CRIS_32_GOTPLT:
case BFD_RELOC_CRIS_32_PLT_GOTREL:
case BFD_RELOC_CRIS_32_PLT_PCREL:
/* We don't want to put in any kind of non-zero bits in the data
being relocated for these. */
break;
case BFD_RELOC_32:
case BFD_RELOC_32_PCREL:
/* No use having warnings here, since most hosts have a 32-bit type
for "long" (which will probably change soon, now that I wrote
this). */
bufp[3] = (val >> 24) & 0xFF;
bufp[2] = (val >> 16) & 0xFF;
bufp[1] = (val >> 8) & 0xFF;
bufp[0] = val & 0xFF;
break;
/* FIXME: The 16 and 8-bit cases should have a way to check
whether a signed or unsigned (or any signedness) number is
accepted.
FIXME: Does the as_bad calls find the line number by themselves,
or should we change them into as_bad_where? */
case BFD_RELOC_16:
case BFD_RELOC_16_PCREL:
if (val > 0xffff || val < -32768)
as_bad (_("Value not in 16 bit range: %ld"), val);
if (! fixP->fx_addsy)
{
bufp[1] = (val >> 8) & 0xFF;
bufp[0] = val & 0xFF;
}
break;
case BFD_RELOC_8:
case BFD_RELOC_8_PCREL:
if (val > 255 || val < -128)
as_bad (_("Value not in 8 bit range: %ld"), val);
if (! fixP->fx_addsy)
bufp[0] = val & 0xFF;
break;
case BFD_RELOC_CRIS_UNSIGNED_4:
if (val > 15 || val < 0)
as_bad (_("Value not in 4 bit unsigned range: %ld"), val);
if (! fixP->fx_addsy)
bufp[0] |= val & 0x0F;
break;
case BFD_RELOC_CRIS_UNSIGNED_5:
if (val > 31 || val < 0)
as_bad (_("Value not in 5 bit unsigned range: %ld"), val);
if (! fixP->fx_addsy)
bufp[0] |= val & 0x1F;
break;
case BFD_RELOC_CRIS_SIGNED_6:
if (val > 31 || val < -32)
as_bad (_("Value not in 6 bit range: %ld"), val);
if (! fixP->fx_addsy)
bufp[0] |= val & 0x3F;
break;
case BFD_RELOC_CRIS_UNSIGNED_6:
if (val > 63 || val < 0)
as_bad (_("Value not in 6 bit unsigned range: %ld"), val);
if (! fixP->fx_addsy)
bufp[0] |= val & 0x3F;
break;
case BFD_RELOC_CRIS_BDISP8:
if (! fixP->fx_addsy)
bufp[0] = branch_disp (val);
break;
case BFD_RELOC_NONE:
/* May actually happen automatically. For example at broken
words, if the word turns out not to be broken.
FIXME: When? Which testcase? */
if (! fixP->fx_addsy)
md_number_to_chars (bufp, val, n);
break;
case BFD_RELOC_VTABLE_INHERIT:
/* This borrowed from tc-ppc.c on a whim. */
if (fixP->fx_addsy
&& !S_IS_DEFINED (fixP->fx_addsy)
&& !S_IS_WEAK (fixP->fx_addsy))
S_SET_WEAK (fixP->fx_addsy);
/* Fall through. */
case BFD_RELOC_VTABLE_ENTRY:
fixP->fx_done = 0;
break;
default:
BAD_CASE (fixP->fx_r_type);
}
}
/* Processes machine-dependent command line options. Called once for
each option on the command line that the machine-independent part of
GAS does not understand. */
int
md_parse_option (arg, argp)
int arg;
char *argp ATTRIBUTE_UNUSED;
{
switch (arg)
{
case 'H':
case 'h':
printf (_("Please use --help to see usage and options for this assembler.\n"));
md_show_usage (stdout);
exit (EXIT_SUCCESS);
case 'N':
warn_for_branch_expansion = 1;
return 1;
case OPTION_NO_US:
demand_register_prefix = true;
if (OUTPUT_FLAVOR == bfd_target_aout_flavour)
as_bad (_("--no-underscore is invalid with a.out format"));
else
symbols_have_leading_underscore = false;
return 1;
case OPTION_US:
demand_register_prefix = false;
symbols_have_leading_underscore = true;
return 1;
case OPTION_PIC:
pic = true;
return 1;
default:
return 0;
}
}
/* Round up a section size to the appropriate boundary. */
valueT
md_section_align (segment, size)
segT segment;
valueT size;
{
/* Round all sects to multiple of 4, except the bss section, which
we'll round to word-size.
FIXME: Check if this really matters. All sections should be
rounded up, and all sections should (optionally) be assumed to be
dword-aligned, it's just that there is actual usage of linking to a
multiple of two. */
if (OUTPUT_FLAVOR == bfd_target_aout_flavour)
{
if (segment == bss_section)
return (size + 1) & ~1;
return (size + 3) & ~3;
}
else
{
/* FIXME: Is this wanted? It matches the testsuite, but that's not
really a valid reason. */
if (segment == text_section)
return (size + 3) & ~3;
}
return size;
}
/* Generate a machine-dependent relocation. */
arelent *
tc_gen_reloc (section, fixP)
asection *section ATTRIBUTE_UNUSED;
fixS *fixP;
{
arelent *relP;
bfd_reloc_code_real_type code;
switch (fixP->fx_r_type)
{
case BFD_RELOC_CRIS_16_GOT:
case BFD_RELOC_CRIS_32_GOT:
case BFD_RELOC_CRIS_16_GOTPLT:
case BFD_RELOC_CRIS_32_GOTPLT:
case BFD_RELOC_CRIS_32_GOTREL:
case BFD_RELOC_CRIS_32_PLT_GOTREL:
case BFD_RELOC_CRIS_32_PLT_PCREL:
case BFD_RELOC_32:
case BFD_RELOC_16:
case BFD_RELOC_8:
case BFD_RELOC_VTABLE_INHERIT:
case BFD_RELOC_VTABLE_ENTRY:
code = fixP->fx_r_type;
break;
default:
as_bad_where (fixP->fx_file, fixP->fx_line,
_("Semantics error. This type of operand can not be relocated, it must be an assembly-time constant"));
return 0;
}
relP = (arelent *) xmalloc (sizeof (arelent));
assert (relP != 0);
relP->sym_ptr_ptr = (asymbol **) xmalloc (sizeof (asymbol *));
*relP->sym_ptr_ptr = symbol_get_bfdsym (fixP->fx_addsy);
relP->address = fixP->fx_frag->fr_address + fixP->fx_where;
if (fixP->fx_pcrel)
/* FIXME: Is this correct? */
relP->addend = fixP->fx_addnumber;
else
/* At least *this one* is correct. */
relP->addend = fixP->fx_offset;
/* This is the standard place for KLUDGEs to work around bugs in
bfd_install_relocation (first such note in the documentation
appears with binutils-2.8).
That function bfd_install_relocation does the wrong thing with
putting stuff into the addend of a reloc (it should stay out) for a
weak symbol. The really bad thing is that it adds the
"segment-relative offset" of the symbol into the reloc. In this
case, the reloc should instead be relative to the symbol with no
other offset than the assembly code shows; and since the symbol is
weak, any local definition should be ignored until link time (or
thereafter).
To wit: weaksym+42 should be weaksym+42 in the reloc,
not weaksym+(offset_from_segment_of_local_weaksym_definition)
To "work around" this, we subtract the segment-relative offset of
"known" weak symbols. This evens out the extra offset.
That happens for a.out but not for ELF, since for ELF,
bfd_install_relocation uses the "special function" field of the
howto, and does not execute the code that needs to be undone. */
if (OUTPUT_FLAVOR == bfd_target_aout_flavour
&& fixP->fx_addsy && S_IS_WEAK (fixP->fx_addsy)
&& ! bfd_is_und_section (S_GET_SEGMENT (fixP->fx_addsy)))
{
relP->addend -= S_GET_VALUE (fixP->fx_addsy);
}
relP->howto = bfd_reloc_type_lookup (stdoutput, code);
if (! relP->howto)
{
const char *name;
name = S_GET_NAME (fixP->fx_addsy);
if (name == NULL)
name = _("<unknown>");
as_fatal (_("Cannot generate relocation type for symbol %s, code %s"),
name, bfd_get_reloc_code_name (code));
}
return relP;
}
/* Machine-dependent usage-output. */
void
md_show_usage (stream)
FILE *stream;
{
/* The messages are formatted to line up with the generic options. */
fprintf (stream, _("CRIS-specific options:\n"));
fprintf (stream, "%s",
_(" -h, -H Don't execute, print this help text. Deprecated.\n"));
fprintf (stream, "%s",
_(" -N Warn when branches are expanded to jumps.\n"));
fprintf (stream, "%s",
_(" --underscore User symbols are normally prepended with underscore.\n"));
fprintf (stream, "%s",
_(" Registers will not need any prefix.\n"));
fprintf (stream, "%s",
_(" --no-underscore User symbols do not have any prefix.\n"));
fprintf (stream, "%s",
_(" Registers will require a `$'-prefix.\n"));
fprintf (stream, "%s",
_(" --pic Enable generation of position-independent code.\n"));
}
/* Apply a fixS (fixup of an instruction or data that we didn't have
enough info to complete immediately) to the data in a frag. */
void
md_apply_fix3 (fixP, valP, seg)
fixS *fixP;
valueT *valP;
segT seg;
{
/* This assignment truncates upper bits if valueT is 64 bits (as with
--enable-64-bit-bfd), which is fine here, though we cast to avoid
any compiler warnings. */
long val = (long) *valP;
char *buf = fixP->fx_where + fixP->fx_frag->fr_literal;
if (fixP->fx_addsy == 0 && !fixP->fx_pcrel)
fixP->fx_done = 1;
if (fixP->fx_bit_fixP || fixP->fx_im_disp != 0)
{
as_bad_where (fixP->fx_file, fixP->fx_line, _("Invalid relocation"));
fixP->fx_done = 1;
}
else
{
/* I took this from tc-arc.c, since we used to not support
fx_subsy != NULL. I'm not totally sure it's TRT. */
if (fixP->fx_subsy != (symbolS *) NULL)
{
if (S_GET_SEGMENT (fixP->fx_subsy) == absolute_section)
val -= S_GET_VALUE (fixP->fx_subsy);
else
/* We can't actually support subtracting a symbol. */
as_bad_where (fixP->fx_file, fixP->fx_line,
_("expression too complex"));
}
cris_number_to_imm (buf, val, fixP->fx_size, fixP, seg);
}
}
/* All relocations are relative to the location just after the fixup;
the address of the fixup plus its size. */
long
md_pcrel_from (fixP)
fixS *fixP;
{
valueT addr = fixP->fx_where + fixP->fx_frag->fr_address;
/* FIXME: We get here only at the end of assembly, when X in ".-X" is
still unknown. Since we don't have pc-relative relocations in a.out,
this is invalid. What to do if anything for a.out, is to add
pc-relative relocations everywhere including the elinux program
loader. For ELF, allow straight-forward PC-relative relocations,
which are always relative to the location after the relocation. */
if (OUTPUT_FLAVOR != bfd_target_elf_flavour
|| (fixP->fx_r_type != BFD_RELOC_8_PCREL
&& fixP->fx_r_type != BFD_RELOC_16_PCREL
&& fixP->fx_r_type != BFD_RELOC_32_PCREL))
as_bad_where (fixP->fx_file, fixP->fx_line,
_("Invalid pc-relative relocation"));
return fixP->fx_size + addr;
}
/* We have no need to give defaults for symbol-values. */
symbolS *
md_undefined_symbol (name)
char *name ATTRIBUTE_UNUSED;
{
return 0;
}
/* Definition of TC_FORCE_RELOCATION.
FIXME: Unsure of this. Can we omit it? Just copied from tc-i386.c
when doing multi-object format with ELF, since it's the only other
multi-object-format target with a.out and ELF. */
int
md_cris_force_relocation (fixp)
struct fix *fixp;
{
switch (fixp->fx_r_type)
{
case BFD_RELOC_VTABLE_INHERIT:
case BFD_RELOC_VTABLE_ENTRY:
case BFD_RELOC_CRIS_16_GOT:
case BFD_RELOC_CRIS_32_GOT:
case BFD_RELOC_CRIS_16_GOTPLT:
case BFD_RELOC_CRIS_32_GOTPLT:
case BFD_RELOC_CRIS_32_GOTREL:
case BFD_RELOC_CRIS_32_PLT_GOTREL:
case BFD_RELOC_CRIS_32_PLT_PCREL:
return 1;
default:
;
}
return 0;
}
/* Check and emit error if broken-word handling has failed to fix up a
case-table. This is called from write.c, after doing everything it
knows about how to handle broken words. */
void
tc_cris_check_adjusted_broken_word (new_offset, brokwP)
offsetT new_offset;
struct broken_word *brokwP;
{
if (new_offset > 32767 || new_offset < -32768)
/* We really want a genuine error, not a warning, so make it one. */
as_bad_where (brokwP->frag->fr_file, brokwP->frag->fr_line,
_("Adjusted signed .word (%ld) overflows: `switch'-statement too large."),
(long) new_offset);
}
/* Make a leading REGISTER_PREFIX_CHAR mandatory for all registers. */
static void cris_force_reg_prefix ()
{
demand_register_prefix = true;
}
/* Do not demand a leading REGISTER_PREFIX_CHAR for all registers. */
static void cris_relax_reg_prefix ()
{
demand_register_prefix = false;
}
/* Adjust for having a leading '_' on all user symbols. */
static void cris_sym_leading_underscore ()
{
/* We can't really do anything more than assert that what the program
thinks symbol starts with agrees with the command-line options, since
the bfd is already created. */
if (symbols_have_leading_underscore == false)
as_bad (_(".syntax %s requires command-line option `--underscore'"),
SYNTAX_USER_SYM_LEADING_UNDERSCORE);
}
/* Adjust for not having any particular prefix on user symbols. */
static void cris_sym_no_leading_underscore ()
{
if (symbols_have_leading_underscore == true)
as_bad (_(".syntax %s requires command-line option `--no-underscore'"),
SYNTAX_USER_SYM_NO_LEADING_UNDERSCORE);
}
/* Handle the .syntax pseudo, which takes an argument that decides what
syntax the assembly code has. */
static void
s_syntax (ignore)
int ignore ATTRIBUTE_UNUSED;
{
static const struct syntaxes
{
const char *operand;
void (*fn) PARAMS ((void));
} syntax_table[] =
{{SYNTAX_ENFORCE_REG_PREFIX, cris_force_reg_prefix},
{SYNTAX_RELAX_REG_PREFIX, cris_relax_reg_prefix},
{SYNTAX_USER_SYM_LEADING_UNDERSCORE, cris_sym_leading_underscore},
{SYNTAX_USER_SYM_NO_LEADING_UNDERSCORE, cris_sym_no_leading_underscore}};
const struct syntaxes *sp;
for (sp = syntax_table;
sp < syntax_table + sizeof (syntax_table) / sizeof (syntax_table[0]);
sp++)
{
if (strncmp (input_line_pointer, sp->operand,
strlen (sp->operand)) == 0)
{
(sp->fn) ();
input_line_pointer += strlen (sp->operand);
demand_empty_rest_of_line ();
return;
}
}
as_bad (_("Unknown .syntax operand"));
}
/* Wrapper for dwarf2_directive_file to emit error if this is seen when
not emitting ELF. */
static void
s_cris_file (dummy)
int dummy;
{
if (OUTPUT_FLAVOR != bfd_target_elf_flavour)
as_bad (_("Pseudodirective .file is only valid when generating ELF"));
else
dwarf2_directive_file (dummy);
}
/* Wrapper for dwarf2_directive_loc to emit error if this is seen when not
emitting ELF. */
static void
s_cris_loc (dummy)
int dummy;
{
if (OUTPUT_FLAVOR != bfd_target_elf_flavour)
as_bad (_("Pseudodirective .loc is only valid when generating ELF"));
else
dwarf2_directive_loc (dummy);
}
/*
* Local variables:
* eval: (c-set-style "gnu")
* indent-tabs-mode: t
* End:
*/
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