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/* Altera Nios II assembler.
Copyright (C) 2012-2021 Free Software Foundation, Inc.
Contributed by Nigel Gray (ngray@altera.com).
Contributed by Mentor Graphics, Inc.
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 3, 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, 51 Franklin Street - Fifth Floor, Boston, MA
02110-1301, USA. */
#include "as.h"
#include "opcode/nios2.h"
#include "elf/nios2.h"
#include "tc-nios2.h"
#include "bfd.h"
#include "dwarf2dbg.h"
#include "subsegs.h"
#include "safe-ctype.h"
#include "dw2gencfi.h"
#ifndef OBJ_ELF
/* We are not supporting any other target so we throw a compile time error. */
OBJ_ELF not defined
#endif
/* We can choose our endianness at run-time, regardless of configuration. */
extern int target_big_endian;
/* This array holds the chars that always start a comment. If the
pre-processor is disabled, these aren't very useful. */
const char 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 C style comments are always supported. */
const char line_comment_chars[] = "#";
/* This array holds machine specific line separator characters. */
const char line_separator_chars[] = ";";
/* Chars that can be used to separate mant from exp in floating point nums. */
const char EXP_CHARS[] = "eE";
/* Chars that mean this number is a floating point constant. */
/* As in 0f12.456 */
/* or 0d1.2345e12 */
const char FLT_CHARS[] = "rRsSfFdDxXpP";
/* Also be aware that MAXIMUM_NUMBER_OF_CHARS_FOR_FLOAT may have to be
changed in read.c. Ideally it shouldn't have to know about it at all,
but nothing is ideal around here. */
/* Machine-dependent command-line options. */
const char *md_shortopts = "r";
struct option md_longopts[] = {
#define OPTION_RELAX_ALL (OPTION_MD_BASE + 0)
{"relax-all", no_argument, NULL, OPTION_RELAX_ALL},
#define OPTION_NORELAX (OPTION_MD_BASE + 1)
{"no-relax", no_argument, NULL, OPTION_NORELAX},
#define OPTION_RELAX_SECTION (OPTION_MD_BASE + 2)
{"relax-section", no_argument, NULL, OPTION_RELAX_SECTION},
#define OPTION_EB (OPTION_MD_BASE + 3)
{"EB", no_argument, NULL, OPTION_EB},
#define OPTION_EL (OPTION_MD_BASE + 4)
{"EL", no_argument, NULL, OPTION_EL},
#define OPTION_MARCH (OPTION_MD_BASE + 5)
{"march", required_argument, NULL, OPTION_MARCH}
};
size_t md_longopts_size = sizeof (md_longopts);
/* The assembler supports three different relaxation modes, controlled by
command-line options. */
typedef enum
{
relax_section = 0,
relax_none,
relax_all
} relax_optionT;
/* Struct contains all assembler options set with .set. */
static struct
{
/* .set noat -> noat = 1 allows assembly code to use at without warning
and macro expansions generate a warning.
.set at -> noat = 0, assembly code using at warn but macro expansions
do not generate warnings. */
bool noat;
/* .set nobreak -> nobreak = 1 allows assembly code to use ba,bt without
warning.
.set break -> nobreak = 0, assembly code using ba,bt warns. */
bool nobreak;
/* .cmd line option -relax-all allows all branches and calls to be replaced
with longer versions.
-no-relax inhibits branch/call conversion.
The default value is relax_section, which relaxes branches within
a section. */
relax_optionT relax;
} nios2_as_options = {false, false, relax_section};
typedef struct nios2_insn_reloc
{
/* Any expression in the instruction is parsed into this field,
which is passed to fix_new_exp() to generate a fixup. */
expressionS reloc_expression;
/* The type of the relocation to be applied. */
bfd_reloc_code_real_type reloc_type;
/* PC-relative. */
unsigned int reloc_pcrel;
/* The next relocation to be applied to the instruction. */
struct nios2_insn_reloc *reloc_next;
} nios2_insn_relocS;
/* This struct is used to hold state when assembling instructions. */
typedef struct nios2_insn_info
{
/* Assembled instruction. */
unsigned long insn_code;
/* Constant bits masked into insn_code for self-check mode. */
unsigned long constant_bits;
/* Pointer to the relevant bit of the opcode table. */
const struct nios2_opcode *insn_nios2_opcode;
/* After parsing ptrs to the tokens in the instruction fill this array
it is terminated with a null pointer (hence the first +1).
The second +1 is because in some parts of the code the opcode
is not counted as a token, but still placed in this array. */
const char *insn_tokens[NIOS2_MAX_INSN_TOKENS + 1 + 1];
/* This holds information used to generate fixups
and eventually relocations if it is not null. */
nios2_insn_relocS *insn_reloc;
} nios2_insn_infoS;
/* This struct is used to convert Nios II pseudo-ops into the
corresponding real op. */
typedef struct nios2_ps_insn_info
{
/* Map this pseudo_op... */
const char *pseudo_insn;
/* ...to this real instruction. */
const char *insn;
/* Call this function to modify the operands.... */
void (*arg_modifer_func) (char ** parsed_args, const char *arg, int num,
int start);
/* ...with these arguments. */
const char *arg_modifier;
int num;
int index;
/* If arg_modifier_func allocates new memory, provide this function
to free it afterwards. */
void (*arg_cleanup_func) (char **parsed_args, int num, int start);
} nios2_ps_insn_infoS;
/* Opcode hash table. */
static htab_t nios2_opcode_hash = NULL;
#define nios2_opcode_lookup(NAME) \
((struct nios2_opcode *) str_hash_find (nios2_opcode_hash, (NAME)))
/* Register hash table. */
static htab_t nios2_reg_hash = NULL;
#define nios2_reg_lookup(NAME) \
((struct nios2_reg *) str_hash_find (nios2_reg_hash, (NAME)))
/* Pseudo-op hash table. */
static htab_t nios2_ps_hash = NULL;
#define nios2_ps_lookup(NAME) \
((nios2_ps_insn_infoS *) str_hash_find (nios2_ps_hash, (NAME)))
/* The known current alignment of the current section. */
static int nios2_current_align;
static segT nios2_current_align_seg;
static int nios2_auto_align_on = 1;
/* The last seen label in the current section. This is used to auto-align
labels preceding instructions. */
static symbolS *nios2_last_label;
/* If we saw a 16-bit CDX instruction, we can align on 2-byte boundaries
instead of 4-bytes. Use this to keep track of the minimum power-of-2
alignment. */
static int nios2_min_align = 2;
#ifdef OBJ_ELF
/* Pre-defined "_GLOBAL_OFFSET_TABLE_" */
symbolS *GOT_symbol;
#endif
/* The processor architecture value, EF_NIOS2_ARCH_R1 by default. */
static int nios2_architecture = EF_NIOS2_ARCH_R1;
/** Utility routines. */
/* Function md_chars_to_number takes the sequence of
bytes in buf and returns the corresponding value
in an int. n must be 1, 2 or 4. */
static valueT
md_chars_to_number (char *buf, int n)
{
int i;
valueT val;
gas_assert (n == 1 || n == 2 || n == 4);
val = 0;
if (target_big_endian)
for (i = 0; i < n; ++i)
val = val | ((valueT) (buf[i] & 0xff) << 8 * (n - (i + 1)));
else
for (i = 0; i < n; ++i)
val = val | ((valueT) (buf[i] & 0xff) << 8 * i);
return val;
}
/* This function turns a C long int, short int or char
into the series of bytes that represent the number
on the target machine. */
void
md_number_to_chars (char *buf, valueT val, int n)
{
gas_assert (n == 1 || n == 2 || n == 4 || n == 8);
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. */
const char *
md_atof (int type, char *litP, int *sizeP)
{
int prec;
LITTLENUM_TYPE words[4];
char *t;
int i;
switch (type)
{
case 'f':
prec = 2;
break;
case 'd':
prec = 4;
break;
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 * 2;
if (! target_big_endian)
for (i = prec - 1; i >= 0; i--, litP += 2)
md_number_to_chars (litP, (valueT) words[i], 2);
else
for (i = 0; i < prec; i++, litP += 2)
md_number_to_chars (litP, (valueT) words[i], 2);
return NULL;
}
/* Return true if STR is prefixed with a special relocation operator. */
static int
nios2_special_relocation_p (const char *str)
{
return (startswith (str, "%lo")
|| startswith (str, "%hi")
|| startswith (str, "%hiadj")
|| startswith (str, "%gprel")
|| startswith (str, "%got")
|| startswith (str, "%call")
|| startswith (str, "%gotoff_lo")
|| startswith (str, "%gotoff_hiadj")
|| startswith (str, "%tls_gd")
|| startswith (str, "%tls_ldm")
|| startswith (str, "%tls_ldo")
|| startswith (str, "%tls_ie")
|| startswith (str, "%tls_le")
|| startswith (str, "%gotoff"));
}
/* nop fill patterns for text section. */
static char const nop_r1[4] = { 0x3a, 0x88, 0x01, 0x00 };
static char const nop_r2[4] = { 0x20, 0x00, 0x00, 0xc4 };
static char const nop_r2_cdx[2] = { 0x3b, 0x00 };
static char const *nop32 = nop_r1;
static char const *nop16 = NULL;
/* Handles all machine-dependent alignment needs. */
static void
nios2_align (int log_size, const char *pfill, symbolS *label)
{
int align;
long max_alignment = 15;
/* The front end is prone to changing segments out from under us
temporarily when -g is in effect. */
int switched_seg_p = (nios2_current_align_seg != now_seg);
align = log_size;
if (align > max_alignment)
{
align = max_alignment;
as_bad (_("Alignment too large: %d. assumed"), align);
}
else if (align < 0)
{
as_warn (_("Alignment negative: 0 assumed"));
align = 0;
}
if (align != 0)
{
if (subseg_text_p (now_seg) && align >= nios2_min_align)
{
/* First, make sure we're on the minimum boundary, in case
someone has been putting .byte values the text section. */
if (nios2_current_align < nios2_min_align || switched_seg_p)
frag_align (nios2_min_align, 0, 0);
/* If we might be on a 2-byte boundary, first align to a
4-byte boundary using the 2-byte nop as fill. */
if (nios2_min_align == 1
&& align > nios2_min_align
&& pfill == nop32 )
{
gas_assert (nop16);
frag_align_pattern (2, nop16, 2, 0);
}
/* Now fill in the alignment pattern. */
if (pfill != NULL)
frag_align_pattern (align, pfill, 4, 0);
else
frag_align (align, 0, 0);
}
else
frag_align (align, 0, 0);
if (!switched_seg_p)
nios2_current_align = align;
/* If the last label was in a different section we can't align it. */
if (label != NULL && !switched_seg_p)
{
symbolS *sym;
int label_seen = false;
struct frag *old_frag;
valueT old_value;
valueT new_value;
gas_assert (S_GET_SEGMENT (label) == now_seg);
old_frag = symbol_get_frag (label);
old_value = S_GET_VALUE (label);
new_value = (valueT) frag_now_fix ();
/* It is possible to have more than one label at a particular
address, especially if debugging is enabled, so we must
take care to adjust all the labels at this address in this
fragment. To save time we search from the end of the symbol
list, backwards, since the symbols we are interested in are
almost certainly the ones that were most recently added.
Also to save time we stop searching once we have seen at least
one matching label, and we encounter a label that is no longer
in the target fragment. Note, this search is guaranteed to
find at least one match when sym == label, so no special case
code is necessary. */
for (sym = symbol_lastP; sym != NULL; sym = symbol_previous (sym))
if (symbol_get_frag (sym) == old_frag
&& S_GET_VALUE (sym) == old_value)
{
label_seen = true;
symbol_set_frag (sym, frag_now);
S_SET_VALUE (sym, new_value);
}
else if (label_seen && symbol_get_frag (sym) != old_frag)
break;
}
record_alignment (now_seg, align);
}
}
/** Support for self-check mode. */
/* Mode of the assembler. */
typedef enum
{
NIOS2_MODE_ASSEMBLE, /* Ordinary operation. */
NIOS2_MODE_TEST /* Hidden mode used for self testing. */
} NIOS2_MODE;
static NIOS2_MODE nios2_mode = NIOS2_MODE_ASSEMBLE;
/* This function is used to in self-checking mode
to check the assembled instruction
opcode should be the assembled opcode, and exp_opcode
the parsed string representing the expected opcode. */
static void
nios2_check_assembly (unsigned int opcode, const char *exp_opcode)
{
if (nios2_mode == NIOS2_MODE_TEST)
{
if (exp_opcode == NULL)
as_bad (_("expecting opcode string in self test mode"));
else if (opcode != strtoul (exp_opcode, NULL, 16))
as_bad (_("assembly 0x%08x, expected %s"), opcode, exp_opcode);
}
}
/** Support for machine-dependent assembler directives. */
/* Handle the .align pseudo-op. This aligns to a power of two. It
also adjusts any current instruction label. We treat this the same
way the MIPS port does: .align 0 turns off auto alignment. */
static void
s_nios2_align (int ignore ATTRIBUTE_UNUSED)
{
int align;
char fill;
const char *pfill = NULL;
long max_alignment = 15;
align = get_absolute_expression ();
if (align > max_alignment)
{
align = max_alignment;
as_bad (_("Alignment too large: %d. assumed"), align);
}
else if (align < 0)
{
as_warn (_("Alignment negative: 0 assumed"));
align = 0;
}
if (*input_line_pointer == ',')
{
input_line_pointer++;
fill = get_absolute_expression ();
pfill = (const char *) &fill;
}
else if (subseg_text_p (now_seg))
pfill = (const char *) nop32;
else
{
pfill = NULL;
nios2_last_label = NULL;
}
if (align != 0)
{
nios2_auto_align_on = 1;
nios2_align (align, pfill, nios2_last_label);
nios2_last_label = NULL;
}
else
nios2_auto_align_on = 0;
demand_empty_rest_of_line ();
}
/* Handle the .text pseudo-op. This is like the usual one, but it
clears the saved last label and resets known alignment. */
static void
s_nios2_text (int i)
{
s_text (i);
nios2_last_label = NULL;
nios2_current_align = 0;
nios2_current_align_seg = now_seg;
}
/* Handle the .data pseudo-op. This is like the usual one, but it
clears the saved last label and resets known alignment. */
static void
s_nios2_data (int i)
{
s_data (i);
nios2_last_label = NULL;
nios2_current_align = 0;
nios2_current_align_seg = now_seg;
}
/* Handle the .section pseudo-op. This is like the usual one, but it
clears the saved last label and resets known alignment. */
static void
s_nios2_section (int ignore)
{
obj_elf_section (ignore);
nios2_last_label = NULL;
nios2_current_align = 0;
nios2_current_align_seg = now_seg;
}
/* Explicitly unaligned cons. */
static void
s_nios2_ucons (int nbytes)
{
int hold;
hold = nios2_auto_align_on;
nios2_auto_align_on = 0;
cons (nbytes);
nios2_auto_align_on = hold;
}
/* Handle the .sdata directive. */
static void
s_nios2_sdata (int ignore ATTRIBUTE_UNUSED)
{
get_absolute_expression (); /* Ignored. */
subseg_new (".sdata", 0);
demand_empty_rest_of_line ();
}
/* .set sets assembler options eg noat/at and is also used
to set symbol values (.equ, .equiv ). */
static void
s_nios2_set (int equiv)
{
char *save = input_line_pointer;
char *directive;
char delim = get_symbol_name (&directive);
char *endline = input_line_pointer;
(void) restore_line_pointer (delim);
/* We only want to handle ".set XXX" if the
user has tried ".set XXX, YYY" they are not
trying a directive. This prevents
us from polluting the name space. */
SKIP_WHITESPACE ();
if (is_end_of_line[(unsigned char) *input_line_pointer])
{
bool done = true;
*endline = 0;
if (!strcmp (directive, "noat"))
nios2_as_options.noat = true;
else if (!strcmp (directive, "at"))
nios2_as_options.noat = false;
else if (!strcmp (directive, "nobreak"))
nios2_as_options.nobreak = true;
else if (!strcmp (directive, "break"))
nios2_as_options.nobreak = false;
else if (!strcmp (directive, "norelax"))
nios2_as_options.relax = relax_none;
else if (!strcmp (directive, "relaxsection"))
nios2_as_options.relax = relax_section;
else if (!strcmp (directive, "relaxall"))
nios2_as_options.relax = relax_all;
else
done = false;
if (done)
{
*endline = delim;
demand_empty_rest_of_line ();
return;
}
}
/* If we fall through to here, either we have ".set XXX, YYY"
or we have ".set XXX" where XXX is unknown or we have
a syntax error. */
input_line_pointer = save;
s_set (equiv);
}
/* Machine-dependent assembler directives.
Format of each entry is:
{ "directive", handler_func, param } */
const pseudo_typeS md_pseudo_table[] = {
{"align", s_nios2_align, 0},
{"text", s_nios2_text, 0},
{"data", s_nios2_data, 0},
{"section", s_nios2_section, 0},
{"section.s", s_nios2_section, 0},
{"sect", s_nios2_section, 0},
{"sect.s", s_nios2_section, 0},
/* .dword and .half are included for compatibility with MIPS. */
{"dword", cons, 8},
{"half", cons, 2},
/* NIOS2 native word size is 4 bytes, so we override
the GAS default of 2. */
{"word", cons, 4},
/* Explicitly unaligned directives. */
{"2byte", s_nios2_ucons, 2},
{"4byte", s_nios2_ucons, 4},
{"8byte", s_nios2_ucons, 8},
{"16byte", s_nios2_ucons, 16},
#ifdef OBJ_ELF
{"sdata", s_nios2_sdata, 0},
#endif
{"set", s_nios2_set, 0},
{NULL, NULL, 0}
};
/** Relaxation support. */
/* We support two relaxation modes: a limited PC-relative mode with
-relax-section (the default), and an absolute jump mode with -relax-all.
Nios II PC-relative branch instructions only support 16-bit offsets.
And, there's no good way to add a 32-bit constant to the PC without
using two registers.
To deal with this, for the pc-relative relaxation mode we convert
br label
into a series of 16-bit adds, like:
nextpc at
addi at, at, 32767
...
addi at, at, remainder
jmp at
Similarly, conditional branches are converted from
b(condition) r, s, label
into a series like:
b(opposite condition) r, s, skip
nextpc at
addi at, at, 32767
...
addi at, at, remainder
jmp at
skip:
The compiler can do a better job, either by converting the branch
directly into a JMP (going through the GOT for PIC) or by allocating
a second register for the 32-bit displacement.
For the -relax-all relaxation mode, the conversions are
movhi at, %hi(symbol+offset)
ori at, %lo(symbol+offset)
jmp at
and
b(opposite condition), r, s, skip
movhi at, %hi(symbol+offset)
ori at, %lo(symbol+offset)
jmp at
skip:
respectively.
16-bit CDX branch instructions are relaxed first into equivalent
32-bit branches and then the above transformations are applied
if necessary.
*/
/* Arbitrarily limit the number of addis we can insert; we need to be able
to specify the maximum growth size for each frag that contains a
relaxable branch. There's no point in specifying a huge number here
since that means the assembler needs to allocate that much extra
memory for every branch, and almost no real code will ever need it.
Plus, as already noted a better solution is to just use a jmp, or
allocate a second register to hold a 32-bit displacement.
FIXME: Rather than making this a constant, it could be controlled by
a command-line argument. */
#define RELAX_MAX_ADDI 32
/* The fr_subtype field represents the target-specific relocation state.
It has type relax_substateT (unsigned int). We use it to track the
number of addis necessary, plus a bit to track whether this is a
conditional branch and a bit for 16-bit CDX instructions.
Regardless of the smaller RELAX_MAX_ADDI limit, we reserve 16 bits
in the fr_subtype to encode the number of addis so that the whole
theoretically-valid range is representable.
For the -relax-all mode, N = 0 represents an in-range branch and N = 1
represents a branch that needs to be relaxed. */
#define UBRANCH (0 << 16)
#define CBRANCH (1 << 16)
#define CDXBRANCH (1 << 17)
#define IS_CBRANCH(SUBTYPE) ((SUBTYPE) & CBRANCH)
#define IS_UBRANCH(SUBTYPE) (!IS_CBRANCH (SUBTYPE))
#define IS_CDXBRANCH(SUBTYPE) ((SUBTYPE) & CDXBRANCH)
#define UBRANCH_SUBTYPE(N) (UBRANCH | (N))
#define CBRANCH_SUBTYPE(N) (CBRANCH | (N))
#define CDX_UBRANCH_SUBTYPE(N) (CDXBRANCH | UBRANCH | (N))
#define CDX_CBRANCH_SUBTYPE(N) (CDXBRANCH | CBRANCH | (N))
#define SUBTYPE_ADDIS(SUBTYPE) ((SUBTYPE) & 0xffff)
/* For the -relax-section mode, unconditional branches require 2 extra
instructions besides the addis, conditional branches require 3. */
#define UBRANCH_ADDIS_TO_SIZE(N) (((N) + 2) * 4)
#define CBRANCH_ADDIS_TO_SIZE(N) (((N) + 3) * 4)
/* For the -relax-all mode, unconditional branches require 3 instructions
and conditional branches require 4. */
#define UBRANCH_JUMP_SIZE 12
#define CBRANCH_JUMP_SIZE 16
/* Maximum sizes of relaxation sequences. */
#define UBRANCH_MAX_SIZE \
(nios2_as_options.relax == relax_all \
? UBRANCH_JUMP_SIZE \
: UBRANCH_ADDIS_TO_SIZE (RELAX_MAX_ADDI))
#define CBRANCH_MAX_SIZE \
(nios2_as_options.relax == relax_all \
? CBRANCH_JUMP_SIZE \
: CBRANCH_ADDIS_TO_SIZE (RELAX_MAX_ADDI))
/* Register number of AT, the assembler temporary. */
#define AT_REGNUM 1
/* Determine how many bytes are required to represent the sequence
indicated by SUBTYPE. */
static int
nios2_relax_subtype_size (relax_substateT subtype)
{
int n = SUBTYPE_ADDIS (subtype);
if (n == 0)
/* Regular conditional/unconditional branch instruction. */
return (IS_CDXBRANCH (subtype) ? 2 : 4);
else if (nios2_as_options.relax == relax_all)
return (IS_CBRANCH (subtype) ? CBRANCH_JUMP_SIZE : UBRANCH_JUMP_SIZE);
else if (IS_CBRANCH (subtype))
return CBRANCH_ADDIS_TO_SIZE (n);
else
return UBRANCH_ADDIS_TO_SIZE (n);
}
/* Estimate size of fragp before relaxation.
This could also examine the offset in fragp and adjust
fragp->fr_subtype, but we will do that in nios2_relax_frag anyway. */
int
md_estimate_size_before_relax (fragS *fragp, segT segment ATTRIBUTE_UNUSED)
{
return nios2_relax_subtype_size (fragp->fr_subtype);
}
/* Implement md_relax_frag, returning the change in size of the frag. */
long
nios2_relax_frag (segT segment, fragS *fragp, long stretch)
{
addressT target = fragp->fr_offset;
relax_substateT subtype = fragp->fr_subtype;
symbolS *symbolp = fragp->fr_symbol;
if (symbolp)
{
fragS *sym_frag = symbol_get_frag (symbolp);
offsetT offset;
int n;
bool is_cdx = false;
target += S_GET_VALUE (symbolp);
/* See comments in write.c:relax_frag about handling of stretch. */
if (stretch != 0
&& sym_frag->relax_marker != fragp->relax_marker)
{
if (stretch < 0 || sym_frag->region == fragp->region)
target += stretch;
else if (target < fragp->fr_address)
target = fragp->fr_next->fr_address + stretch;
}
/* We subtract fr_var (4 for 32-bit insns) because all pc relative
branches are from the next instruction. */
offset = target - fragp->fr_address - fragp->fr_fix - fragp->fr_var;
if (IS_CDXBRANCH (subtype) && IS_UBRANCH (subtype)
&& offset >= -1024 && offset < 1024)
/* PC-relative CDX branch with 11-bit offset. */
is_cdx = true;
else if (IS_CDXBRANCH (subtype) && IS_CBRANCH (subtype)
&& offset >= -128 && offset < 128)
/* PC-relative CDX branch with 8-bit offset. */
is_cdx = true;
else if (offset >= -32768 && offset < 32768)
/* Fits in PC-relative branch. */
n = 0;
else if (nios2_as_options.relax == relax_all)
/* Convert to jump. */
n = 1;
else if (nios2_as_options.relax == relax_section
&& S_GET_SEGMENT (symbolp) == segment
&& S_IS_DEFINED (symbolp))
/* Attempt a PC-relative relaxation on a branch to a defined
symbol in the same segment. */
{
/* The relaxation for conditional branches is offset by 4
bytes because we insert the inverted branch around the
sequence. */
if (IS_CBRANCH (subtype))
offset = offset - 4;
if (offset > 0)
n = offset / 32767 + 1;
else
n = offset / -32768 + 1;
/* Bail out immediately if relaxation has failed. If we try to
defer the diagnostic to md_convert_frag, some pathological test
cases (e.g. gcc/testsuite/gcc.c-torture/compile/20001226-1.c)
apparently never converge. By returning 0 here we could pretend
to the caller that nothing has changed, but that leaves things
in an inconsistent state when we get to md_convert_frag. */
if (n > RELAX_MAX_ADDI)
{
as_bad_where (fragp->fr_file, fragp->fr_line,
_("branch offset out of range\n"));
as_fatal (_("branch relaxation failed\n"));
}
}
else
/* We cannot handle this case, diagnose overflow later. */
return 0;
if (is_cdx)
fragp->fr_subtype = subtype;
else if (IS_CBRANCH (subtype))
fragp->fr_subtype = CBRANCH_SUBTYPE (n);
else
fragp->fr_subtype = UBRANCH_SUBTYPE (n);
return (nios2_relax_subtype_size (fragp->fr_subtype)
- nios2_relax_subtype_size (subtype));
}
/* If we got here, it's probably an error. */
return 0;
}
/* Complete fragp using the data from the relaxation pass. */
void
md_convert_frag (bfd *headers ATTRIBUTE_UNUSED, segT segment ATTRIBUTE_UNUSED,
fragS *fragp)
{
char *buffer = fragp->fr_literal + fragp->fr_fix;
relax_substateT subtype = fragp->fr_subtype;
int n = SUBTYPE_ADDIS (subtype);
addressT target = fragp->fr_offset;
symbolS *symbolp = fragp->fr_symbol;
offsetT offset;
unsigned int addend_mask, addi_mask, op;
offsetT addend, remainder;
int i;
bool is_r2 = (bfd_get_mach (stdoutput) == bfd_mach_nios2r2);
/* If this is a CDX branch we're not relaxing, just generate the fixup. */
if (IS_CDXBRANCH (subtype))
{
gas_assert (is_r2);
fix_new (fragp, fragp->fr_fix, 2, fragp->fr_symbol,
fragp->fr_offset, 1,
(IS_UBRANCH (subtype)
? BFD_RELOC_NIOS2_R2_I10_1_PCREL
: BFD_RELOC_NIOS2_R2_T1I7_1_PCREL));
fragp->fr_fix += 2;
return;
}
/* If this is a CDX branch we are relaxing, turn it into an equivalent
32-bit branch and then fall through to the normal non-CDX cases. */
if (fragp->fr_var == 2)
{
unsigned int opcode = md_chars_to_number (buffer, 2);
gas_assert (is_r2);
if (IS_CBRANCH (subtype))
{
unsigned int reg = nios2_r2_reg3_mappings[GET_IW_T1I7_A3 (opcode)];
if (GET_IW_R2_OP (opcode) == R2_OP_BNEZ_N)
opcode = MATCH_R2_BNE | SET_IW_F2I16_A (reg);
else
opcode = MATCH_R2_BEQ | SET_IW_F2I16_A (reg);
}
else
opcode = MATCH_R2_BR;
md_number_to_chars (buffer, opcode, 4);
fragp->fr_var = 4;
}
/* If we didn't or can't relax, this is a regular branch instruction.
We just need to generate the fixup for the symbol and offset. */
if (n == 0)
{
fix_new (fragp, fragp->fr_fix, 4, fragp->fr_symbol,
fragp->fr_offset, 1, BFD_RELOC_16_PCREL);
fragp->fr_fix += 4;
return;
}
/* Replace the cbranch at fr_fix with one that has the opposite condition
in order to jump around the block of instructions we'll be adding. */
if (IS_CBRANCH (subtype))
{
unsigned int br_opcode;
unsigned int old_op, new_op;
int nbytes;
/* Account for the nextpc and jmp in the pc-relative case, or the two
load instructions and jump in the absolute case. */
if (nios2_as_options.relax == relax_section)
nbytes = (n + 2) * 4;
else
nbytes = 12;
br_opcode = md_chars_to_number (buffer, 4);
if (is_r2)
{
old_op = GET_IW_R2_OP (br_opcode);
switch (old_op)
{
case R2_OP_BEQ:
new_op = R2_OP_BNE;
break;
case R2_OP_BNE:
new_op = R2_OP_BEQ;
break;
case R2_OP_BGE:
new_op = R2_OP_BLT;
break;
case R2_OP_BGEU:
new_op = R2_OP_BLTU;
break;
case R2_OP_BLT:
new_op = R2_OP_BGE;
break;
case R2_OP_BLTU:
new_op = R2_OP_BGEU;
break;
default:
abort ();
}
br_opcode = ((br_opcode & ~IW_R2_OP_SHIFTED_MASK)
| SET_IW_R2_OP (new_op));
br_opcode = br_opcode | SET_IW_F2I16_IMM16 (nbytes);
}
else
{
old_op = GET_IW_R1_OP (br_opcode);
switch (old_op)
{
case R1_OP_BEQ:
new_op = R1_OP_BNE;
break;
case R1_OP_BNE:
new_op = R1_OP_BEQ;
break;
case R1_OP_BGE:
new_op = R1_OP_BLT;
break;
case R1_OP_BGEU:
new_op = R1_OP_BLTU;
break;
case R1_OP_BLT:
new_op = R1_OP_BGE;
break;
case R1_OP_BLTU:
new_op = R1_OP_BGEU;
break;
default:
abort ();
}
br_opcode = ((br_opcode & ~IW_R1_OP_SHIFTED_MASK)
| SET_IW_R1_OP (new_op));
br_opcode = br_opcode | SET_IW_I_IMM16 (nbytes);
}
md_number_to_chars (buffer, br_opcode, 4);
fragp->fr_fix += 4;
buffer += 4;
}
/* Load at for the PC-relative case. */
if (nios2_as_options.relax == relax_section)
{
/* Insert the nextpc instruction. */
if (is_r2)
op = MATCH_R2_NEXTPC | SET_IW_F3X6L5_C (AT_REGNUM);
else
op = MATCH_R1_NEXTPC | SET_IW_R_C (AT_REGNUM);
md_number_to_chars (buffer, op, 4);
fragp->fr_fix += 4;
buffer += 4;
/* We need to know whether the offset is positive or negative. */
target += S_GET_VALUE (symbolp);
offset = target - fragp->fr_address - fragp->fr_fix;
if (offset > 0)
addend = 32767;
else
addend = -32768;
if (is_r2)
addend_mask = SET_IW_F2I16_IMM16 ((unsigned int)addend);
else
addend_mask = SET_IW_I_IMM16 ((unsigned int)addend);
/* Insert n-1 addi instructions. */
if (is_r2)
addi_mask = (MATCH_R2_ADDI
| SET_IW_F2I16_B (AT_REGNUM)
| SET_IW_F2I16_A (AT_REGNUM));
else
addi_mask = (MATCH_R1_ADDI
| SET_IW_I_B (AT_REGNUM)
| SET_IW_I_A (AT_REGNUM));
for (i = 0; i < n - 1; i ++)
{
md_number_to_chars (buffer, addi_mask | addend_mask, 4);
fragp->fr_fix += 4;
buffer += 4;
}
/* Insert the last addi instruction to hold the remainder. */
remainder = offset - addend * (n - 1);
gas_assert (remainder >= -32768 && remainder <= 32767);
if (is_r2)
addend_mask = SET_IW_F2I16_IMM16 ((unsigned int)remainder);
else
addend_mask = SET_IW_I_IMM16 ((unsigned int)remainder);
md_number_to_chars (buffer, addi_mask | addend_mask, 4);
fragp->fr_fix += 4;
buffer += 4;
}
/* Load at for the absolute case. */
else
{
if (is_r2)
op = MATCH_R2_ORHI | SET_IW_F2I16_B (AT_REGNUM) | SET_IW_F2I16_A (0);
else
op = MATCH_R1_ORHI | SET_IW_I_B (AT_REGNUM) | SET_IW_I_A (0);
md_number_to_chars (buffer, op, 4);
fix_new (fragp, fragp->fr_fix, 4, fragp->fr_symbol, fragp->fr_offset,
0, BFD_RELOC_NIOS2_HI16);
fragp->fr_fix += 4;
buffer += 4;
if (is_r2)
op = (MATCH_R2_ORI | SET_IW_F2I16_B (AT_REGNUM)
| SET_IW_F2I16_A (AT_REGNUM));
else
op = (MATCH_R1_ORI | SET_IW_I_B (AT_REGNUM)
| SET_IW_I_A (AT_REGNUM));
md_number_to_chars (buffer, op, 4);
fix_new (fragp, fragp->fr_fix, 4, fragp->fr_symbol, fragp->fr_offset,
0, BFD_RELOC_NIOS2_LO16);
fragp->fr_fix += 4;
buffer += 4;
}
/* Insert the jmp instruction. */
if (is_r2)
op = MATCH_R2_JMP | SET_IW_F3X6L5_A (AT_REGNUM);
else
op = MATCH_R1_JMP | SET_IW_R_A (AT_REGNUM);
md_number_to_chars (buffer, op, 4);
fragp->fr_fix += 4;
buffer += 4;
}
/** Fixups and overflow checking. */
/* Check a fixup for overflow. */
static bool
nios2_check_overflow (valueT fixup, reloc_howto_type *howto)
{
/* If there is a rightshift, check that the low-order bits are
zero before applying it. */
if (howto->rightshift)
{
if ((~(~((valueT) 0) << howto->rightshift) & fixup)
&& howto->complain_on_overflow != complain_overflow_dont)
return true;
fixup = ((signed)fixup) >> howto->rightshift;
}
/* Check for overflow - return TRUE if overflow, FALSE if not. */
switch (howto->complain_on_overflow)
{
case complain_overflow_dont:
break;
case complain_overflow_bitfield:
if ((fixup >> howto->bitsize) != 0
&& ((signed) fixup >> howto->bitsize) != -1)
return true;
break;
case complain_overflow_signed:
if ((fixup & 0x80000000) > 0)
{
/* Check for negative overflow. */
if ((signed) fixup < (signed) (~0U << (howto->bitsize - 1)))
return true;
}
else
{
/* Check for positive overflow. */
if (fixup >= ((unsigned) 1 << (howto->bitsize - 1)))
return true;
}
break;
case complain_overflow_unsigned:
if ((fixup >> howto->bitsize) != 0)
return true;
break;
default:
as_bad (_("error checking for overflow - broken assembler"));
break;
}
return false;
}
/* Emit diagnostic for fixup overflow. */
static void
nios2_diagnose_overflow (valueT fixup, reloc_howto_type *howto,
fixS *fixP, valueT value)
{
if (fixP->fx_r_type == BFD_RELOC_8
|| fixP->fx_r_type == BFD_RELOC_16
|| fixP->fx_r_type == BFD_RELOC_32)
/* These relocs are against data, not instructions. */
as_bad_where (fixP->fx_file, fixP->fx_line,
_("immediate value 0x%x truncated to 0x%x"),
(unsigned int) fixup,
(unsigned int) (~(~(valueT) 0 << howto->bitsize) & fixup));
else
{
/* What opcode is the instruction? This will determine
whether we check for overflow in immediate values
and what error message we get. */
const struct nios2_opcode *opcode;
enum overflow_type overflow_msg_type;
unsigned int range_min;
unsigned int range_max;
unsigned int address;
opcode = nios2_find_opcode_hash (value, bfd_get_mach (stdoutput));
gas_assert (opcode);
gas_assert (fixP->fx_size == opcode->size);
overflow_msg_type = opcode->overflow_msg;
switch (overflow_msg_type)
{
case call_target_overflow:
range_min
= ((fixP->fx_frag->fr_address + fixP->fx_where) & 0xf0000000);
range_max = range_min + 0x0fffffff;
address = fixup | range_min;
as_bad_where (fixP->fx_file, fixP->fx_line,
_("call target address 0x%08x out of range 0x%08x to 0x%08x"),
address, range_min, range_max);
break;
case branch_target_overflow:
if (opcode->format == iw_i_type || opcode->format == iw_F2I16_type)
as_bad_where (fixP->fx_file, fixP->fx_line,
_("branch offset %d out of range %d to %d"),
(int)fixup, -32768, 32767);
else
as_bad_where (fixP->fx_file, fixP->fx_line,
_("branch offset %d out of range"),
(int)fixup);
break;
case address_offset_overflow:
if (opcode->format == iw_i_type || opcode->format == iw_F2I16_type)
as_bad_where (fixP->fx_file, fixP->fx_line,
_("%s offset %d out of range %d to %d"),
opcode->name, (int)fixup, -32768, 32767);
else
as_bad_where (fixP->fx_file, fixP->fx_line,
_("%s offset %d out of range"),
opcode->name, (int)fixup);
break;
case signed_immed16_overflow:
as_bad_where (fixP->fx_file, fixP->fx_line,
_("immediate value %d out of range %d to %d"),
(int)fixup, -32768, 32767);
break;
case unsigned_immed16_overflow:
as_bad_where (fixP->fx_file, fixP->fx_line,
_("immediate value %u out of range %u to %u"),
(unsigned int)fixup, 0, 65535);
break;
case unsigned_immed5_overflow:
as_bad_where (fixP->fx_file, fixP->fx_line,
_("immediate value %u out of range %u to %u"),
(unsigned int)fixup, 0, 31);
break;
case signed_immed12_overflow:
as_bad_where (fixP->fx_file, fixP->fx_line,
_("immediate value %d out of range %d to %d"),
(int)fixup, -2048, 2047);
break;
case custom_opcode_overflow:
as_bad_where (fixP->fx_file, fixP->fx_line,
_("custom instruction opcode %u out of range %u to %u"),
(unsigned int)fixup, 0, 255);
break;
default:
as_bad_where (fixP->fx_file, fixP->fx_line,
_("overflow in immediate argument"));
break;
}
}
}
/* Apply a fixup to the object file. */
void
md_apply_fix (fixS *fixP, valueT *valP, segT seg ATTRIBUTE_UNUSED)
{
/* Assert that the fixup is one we can handle. */
gas_assert (fixP != NULL && valP != NULL
&& (fixP->fx_r_type == BFD_RELOC_8
|| fixP->fx_r_type == BFD_RELOC_16
|| fixP->fx_r_type == BFD_RELOC_32
|| fixP->fx_r_type == BFD_RELOC_64
|| fixP->fx_r_type == BFD_RELOC_NIOS2_S16
|| fixP->fx_r_type == BFD_RELOC_NIOS2_U16
|| fixP->fx_r_type == BFD_RELOC_16_PCREL
|| fixP->fx_r_type == BFD_RELOC_NIOS2_CALL26
|| fixP->fx_r_type == BFD_RELOC_NIOS2_IMM5
|| fixP->fx_r_type == BFD_RELOC_NIOS2_CACHE_OPX
|| fixP->fx_r_type == BFD_RELOC_NIOS2_IMM6
|| fixP->fx_r_type == BFD_RELOC_NIOS2_IMM8
|| fixP->fx_r_type == BFD_RELOC_NIOS2_HI16
|| fixP->fx_r_type == BFD_RELOC_NIOS2_LO16
|| fixP->fx_r_type == BFD_RELOC_NIOS2_HIADJ16
|| fixP->fx_r_type == BFD_RELOC_NIOS2_GPREL
|| fixP->fx_r_type == BFD_RELOC_VTABLE_INHERIT
|| fixP->fx_r_type == BFD_RELOC_VTABLE_ENTRY
|| fixP->fx_r_type == BFD_RELOC_NIOS2_UJMP
|| fixP->fx_r_type == BFD_RELOC_NIOS2_CJMP
|| fixP->fx_r_type == BFD_RELOC_NIOS2_CALLR
|| fixP->fx_r_type == BFD_RELOC_NIOS2_ALIGN
|| fixP->fx_r_type == BFD_RELOC_NIOS2_GOT16
|| fixP->fx_r_type == BFD_RELOC_NIOS2_CALL16
|| fixP->fx_r_type == BFD_RELOC_NIOS2_GOTOFF_LO
|| fixP->fx_r_type == BFD_RELOC_NIOS2_GOTOFF_HA
|| fixP->fx_r_type == BFD_RELOC_NIOS2_TLS_GD16
|| fixP->fx_r_type == BFD_RELOC_NIOS2_TLS_LDM16
|| fixP->fx_r_type == BFD_RELOC_NIOS2_TLS_LDO16
|| fixP->fx_r_type == BFD_RELOC_NIOS2_TLS_IE16
|| fixP->fx_r_type == BFD_RELOC_NIOS2_TLS_LE16
|| fixP->fx_r_type == BFD_RELOC_NIOS2_GOTOFF
|| fixP->fx_r_type == BFD_RELOC_NIOS2_TLS_DTPREL
|| fixP->fx_r_type == BFD_RELOC_NIOS2_CALL26_NOAT
|| fixP->fx_r_type == BFD_RELOC_NIOS2_GOT_LO
|| fixP->fx_r_type == BFD_RELOC_NIOS2_GOT_HA
|| fixP->fx_r_type == BFD_RELOC_NIOS2_CALL_LO
|| fixP->fx_r_type == BFD_RELOC_NIOS2_CALL_HA
|| fixP->fx_r_type == BFD_RELOC_NIOS2_R2_S12
|| fixP->fx_r_type == BFD_RELOC_NIOS2_R2_I10_1_PCREL
|| fixP->fx_r_type == BFD_RELOC_NIOS2_R2_T1I7_1_PCREL
|| fixP->fx_r_type == BFD_RELOC_NIOS2_R2_T1I7_2
|| fixP->fx_r_type == BFD_RELOC_NIOS2_R2_T2I4
|| fixP->fx_r_type == BFD_RELOC_NIOS2_R2_T2I4_1
|| fixP->fx_r_type == BFD_RELOC_NIOS2_R2_T2I4_2
|| fixP->fx_r_type == BFD_RELOC_NIOS2_R2_X1I7_2
|| fixP->fx_r_type == BFD_RELOC_NIOS2_R2_X2L5
|| fixP->fx_r_type == BFD_RELOC_NIOS2_R2_F1I5_2
|| fixP->fx_r_type == BFD_RELOC_NIOS2_R2_L5I4X1
|| fixP->fx_r_type == BFD_RELOC_NIOS2_R2_T1X1I6
|| fixP->fx_r_type == BFD_RELOC_NIOS2_R2_T1X1I6_2
/* Add other relocs here as we generate them. */
));
if (fixP->fx_r_type == BFD_RELOC_64)
{
/* We may reach here due to .8byte directives, but we never output
BFD_RELOC_64; it must be resolved. */
if (fixP->fx_addsy != NULL)
as_bad_where (fixP->fx_file, fixP->fx_line,
_("cannot create 64-bit relocation"));
else
{
md_number_to_chars (fixP->fx_frag->fr_literal + fixP->fx_where,
*valP, 8);
fixP->fx_done = 1;
}
return;
}
/* The value passed in valP can be the value of a fully
resolved expression, or it can be the value of a partially
resolved expression. In the former case, both fixP->fx_addsy
and fixP->fx_subsy are NULL, and fixP->fx_offset == *valP, and
we can fix up the instruction that fixP relates to.
In the latter case, one or both of fixP->fx_addsy and
fixP->fx_subsy are not NULL, and fixP->fx_offset may or may not
equal *valP. We don't need to check for fixP->fx_subsy being null
because the generic part of the assembler generates an error if
it is not an absolute symbol. */
if (fixP->fx_addsy != NULL)
/* Partially resolved expression. */
{
fixP->fx_addnumber = fixP->fx_offset;
fixP->fx_done = 0;
switch (fixP->fx_r_type)
{
case BFD_RELOC_NIOS2_TLS_GD16:
case BFD_RELOC_NIOS2_TLS_LDM16:
case BFD_RELOC_NIOS2_TLS_LDO16:
case BFD_RELOC_NIOS2_TLS_IE16:
case BFD_RELOC_NIOS2_TLS_LE16:
case BFD_RELOC_NIOS2_TLS_DTPMOD:
case BFD_RELOC_NIOS2_TLS_DTPREL:
case BFD_RELOC_NIOS2_TLS_TPREL:
S_SET_THREAD_LOCAL (fixP->fx_addsy);
break;
default:
break;
}
}
else
/* Fully resolved fixup. */
{
reloc_howto_type *howto
= bfd_reloc_type_lookup (stdoutput, fixP->fx_r_type);
if (howto == NULL)
as_bad_where (fixP->fx_file, fixP->fx_line,
_("relocation is not supported"));
else
{
valueT fixup = *valP;
valueT value;
char *buf;
/* If this is a pc-relative relocation, we need to
subtract the current offset within the object file
FIXME : for some reason fixP->fx_pcrel isn't 1 when it should be
so I'm using the howto structure instead to determine this. */
if (howto->pc_relative == 1)
{
fixup = (fixup - (fixP->fx_frag->fr_address + fixP->fx_where
+ fixP->fx_size));
*valP = fixup;
}
/* Get the instruction or data to be fixed up. */
buf = fixP->fx_frag->fr_literal + fixP->fx_where;
value = md_chars_to_number (buf, fixP->fx_size);
/* Check for overflow, emitting a diagnostic if necessary. */
if (nios2_check_overflow (fixup, howto))
nios2_diagnose_overflow (fixup, howto, fixP, value);
/* Apply the right shift. */
fixup = (offsetT) fixup >> howto->rightshift;
/* Truncate the fixup to right size. */
switch (fixP->fx_r_type)
{
case BFD_RELOC_NIOS2_HI16:
fixup = (fixup >> 16) & 0xFFFF;
break;
case BFD_RELOC_NIOS2_LO16:
fixup = fixup & 0xFFFF;
break;
case BFD_RELOC_NIOS2_HIADJ16:
fixup = ((fixup + 0x8000) >> 16) & 0xFFFF;
break;
default:
{
fixup &= ((valueT) 2 << (howto->bitsize - 1)) - 1;
break;
}
}
/* Fix up the instruction. */
value = (value & ~howto->dst_mask) | (fixup << howto->bitpos);
md_number_to_chars (buf, value, fixP->fx_size);
}
fixP->fx_done = 1;
}
if (fixP->fx_r_type == BFD_RELOC_VTABLE_INHERIT)
{
fixP->fx_done = 0;
if (fixP->fx_addsy
&& !S_IS_DEFINED (fixP->fx_addsy) && !S_IS_WEAK (fixP->fx_addsy))
S_SET_WEAK (fixP->fx_addsy);
}
else if (fixP->fx_r_type == BFD_RELOC_VTABLE_ENTRY)
fixP->fx_done = 0;
}
/** Instruction parsing support. */
/* General internal error routine. */
static void
bad_opcode (const struct nios2_opcode *op)
{
fprintf (stderr, _("internal error: broken opcode descriptor for `%s %s'\n"),
op->name, op->args);
as_fatal (_("Broken assembler. No assembly attempted."));
}
/* Special relocation directive strings. */
struct nios2_special_relocS
{
const char *string;
bfd_reloc_code_real_type reloc_type;
};
/* This table is sorted so that prefix strings are listed after the longer
strings that include them -- e.g., %got after %got_hiadj, etc. */
struct nios2_special_relocS nios2_special_reloc[] = {
{"%hiadj", BFD_RELOC_NIOS2_HIADJ16},
{"%hi", BFD_RELOC_NIOS2_HI16},
{"%lo", BFD_RELOC_NIOS2_LO16},
{"%gprel", BFD_RELOC_NIOS2_GPREL},
{"%call_lo", BFD_RELOC_NIOS2_CALL_LO},
{"%call_hiadj", BFD_RELOC_NIOS2_CALL_HA},
{"%call", BFD_RELOC_NIOS2_CALL16},
{"%gotoff_lo", BFD_RELOC_NIOS2_GOTOFF_LO},
{"%gotoff_hiadj", BFD_RELOC_NIOS2_GOTOFF_HA},
{"%gotoff", BFD_RELOC_NIOS2_GOTOFF},
{"%got_hiadj", BFD_RELOC_NIOS2_GOT_HA},
{"%got_lo", BFD_RELOC_NIOS2_GOT_LO},
{"%got", BFD_RELOC_NIOS2_GOT16},
{"%tls_gd", BFD_RELOC_NIOS2_TLS_GD16},
{"%tls_ldm", BFD_RELOC_NIOS2_TLS_LDM16},
{"%tls_ldo", BFD_RELOC_NIOS2_TLS_LDO16},
{"%tls_ie", BFD_RELOC_NIOS2_TLS_IE16},
{"%tls_le", BFD_RELOC_NIOS2_TLS_LE16},
};
#define NIOS2_NUM_SPECIAL_RELOCS \
(sizeof(nios2_special_reloc)/sizeof(nios2_special_reloc[0]))
const int nios2_num_special_relocs = NIOS2_NUM_SPECIAL_RELOCS;
/* Creates a new nios2_insn_relocS and returns a pointer to it. */
static nios2_insn_relocS *
nios2_insn_reloc_new (bfd_reloc_code_real_type reloc_type, unsigned int pcrel)
{
nios2_insn_relocS *retval;
retval = XNEW (nios2_insn_relocS);
if (retval == NULL)
{
as_bad (_("can't create relocation"));
abort ();
}
/* Fill out the fields with default values. */
retval->reloc_next = NULL;
retval->reloc_type = reloc_type;
retval->reloc_pcrel = pcrel;
return retval;
}
/* Frees up memory previously allocated by nios2_insn_reloc_new(). */
/* FIXME: this is never called; memory leak? */
#if 0
static void
nios2_insn_reloc_destroy (nios2_insn_relocS *reloc)
{
gas_assert (reloc != NULL);
free (reloc);
}
#endif
/* Look up a register name and validate it for the given regtype.
Return the register mapping or NULL on failure. */
static struct nios2_reg *
nios2_parse_reg (const char *token, unsigned long regtype)
{
struct nios2_reg *reg = nios2_reg_lookup (token);
if (reg == NULL)
{
as_bad (_("unknown register %s"), token);
return NULL;
}
/* Matched a register, but is it the wrong type? */
if (!(regtype & reg->regtype))
{
if (regtype & REG_CONTROL)
as_bad (_("expecting control register"));
else if (reg->regtype & REG_CONTROL)
as_bad (_("illegal use of control register"));
else if (reg->regtype & REG_COPROCESSOR)
as_bad (_("illegal use of coprocessor register"));
else
as_bad (_("invalid register %s"), token);
return NULL;
}
/* Warn for explicit use of special registers. */
if (reg->regtype & REG_NORMAL)
{
if (!nios2_as_options.noat && reg->index == 1)
as_warn (_("Register at (r1) can sometimes be corrupted by "
"assembler optimizations.\n"
"Use .set noat to turn off those optimizations "
"(and this warning)."));
if (!nios2_as_options.nobreak && reg->index == 25)
as_warn (_("The debugger will corrupt bt (r25).\n"
"If you don't need to debug this "
"code use .set nobreak to turn off this warning."));
if (!nios2_as_options.nobreak && reg->index == 30)
as_warn (_("The debugger will corrupt sstatus/ba (r30).\n"
"If you don't need to debug this "
"code use .set nobreak to turn off this warning."));
}
return reg;
}
/* This function parses a reglist for ldwm/stwm and push.n/pop.n
instructions, given as a brace-enclosed register list. The tokenizer
has replaced commas in the token with spaces.
The return value is a bitmask of registers in the set. It also
sets nios2_reglist_mask and nios2_reglist_dir to allow error checking
when parsing the base register. */
static unsigned long nios2_reglist_mask;
static int nios2_reglist_dir;
static unsigned long
nios2_parse_reglist (char *token, const struct nios2_opcode *op)
{
unsigned long mask = 0;
int dir = 0;
unsigned long regtype = 0;
int last = -1;
const char *regname;
nios2_reglist_mask = 0;
nios2_reglist_dir = 0;
if (op->match == MATCH_R2_LDWM || op->match == MATCH_R2_STWM)
{
regtype = REG_LDWM;
dir = 0;
}
else if (op->match == MATCH_R2_PUSH_N)
{
regtype = REG_POP;
dir = -1;
}
else if (op->match == MATCH_R2_POP_N)
{
regtype = REG_POP;
dir = 1;
}
else
bad_opcode (op);
for (regname = strtok (token, "{ }");
regname;
regname = strtok (NULL, "{ }"))
{
int regno;
struct nios2_reg *reg = nios2_parse_reg (regname, regtype);
if (!reg)
break;
regno = reg->index;
/* Make sure registers are listed in proper sequence. */
if (last >= 0)
{
if (regno == last)
{
as_bad ("duplicate register %s\n", reg->name);
return 0;
}
else if (dir == 0)
dir = (regno < last ? -1 : 1);
else if ((dir > 0 && regno < last)
|| (dir < 0 && regno > last)
|| (op->match == MATCH_R2_PUSH_N
&& ! ((last == 31 && regno == 28)
|| (last == 31 && regno <= 23)
|| (last == 28 && regno <= 23)
|| (regno < 23 && regno == last - 1)))
|| (op->match == MATCH_R2_POP_N
&& ! ((regno == 31 && last == 28)
|| (regno == 31 && last <= 23)
|| (regno == 28 && last <= 23)
|| (last < 23 && last == regno - 1))))
{
as_bad ("invalid register order");
return 0;
}
}
mask |= 1UL << regno;
last = regno;
}
/* Check that all ldwm/stwm regs belong to the same set. */
if ((op->match == MATCH_R2_LDWM || op->match == MATCH_R2_STWM)
&& (mask & 0x00003ffc) && (mask & 0x90ffc000))
{
as_bad ("invalid register set in reglist");
return 0;
}
/* Check that push.n/pop.n regs include RA. */
if ((op->match == MATCH_R2_PUSH_N || op->match == MATCH_R2_POP_N)
&& ((mask & 0x80000000) == 0))
{
as_bad ("reglist must include ra (r31)");
return 0;
}
/* Check that there is at least one register in the set. */
if (!mask)
{
as_bad ("reglist must include at least one register");
return 0;
}
/* OK, reglist passed validation. */
nios2_reglist_mask = mask;
nios2_reglist_dir = dir;
return mask;
}
/* This function parses the base register and options used by the ldwm/stwm
instructions. Returns the base register and sets the option arguments
accordingly. On failure, returns NULL. */
static struct nios2_reg *
nios2_parse_base_register (char *str, int *direction, int *writeback, int *ret)
{
char *regname;
struct nios2_reg *reg;
*direction = 0;
*writeback = 0;
*ret = 0;
/* Check for --. */
if (startswith (str, "--"))
{
str += 2;
*direction -= 1;
}
/* Extract the base register. */
if (*str != '(')
{
as_bad ("expected '(' before base register");
return NULL;
}
str++;
regname = str;
str = strchr (str, ')');
if (!str)
{
as_bad ("expected ')' after base register");
return NULL;
}
*str = '\0';
str++;
reg = nios2_parse_reg (regname, REG_NORMAL);
if (reg == NULL)
return NULL;
/* Check for ++. */
if (startswith (str, "++"))
{
str += 2;
*direction += 1;
}
/* Ensure that either -- or ++ is specified, but not both. */
if (*direction == 0)
{
as_bad ("invalid base register syntax");
return NULL;;
}
/* Check for options. The tokenizer has replaced commas with spaces. */
while (*str)
{
while (*str == ' ')
str++;
if (startswith (str, "writeback"))
{
*writeback = 1;
str += 9;
}
else if (startswith (str, "ret"))
{
*ret = 1;
str += 3;
}
else if (*str)
{
as_bad ("invalid option syntax");
return NULL;
}
}
return reg;
}
/* The various nios2_assemble_* functions call this
function to generate an expression from a string representing an expression.
It then tries to evaluate the expression, and if it can, returns its value.
If not, it creates a new nios2_insn_relocS and stores the expression and
reloc_type for future use. */
static unsigned long
nios2_assemble_expression (const char *exprstr,
nios2_insn_infoS *insn,
bfd_reloc_code_real_type orig_reloc_type,
unsigned int pcrel)
{
nios2_insn_relocS *reloc;
char *saved_line_ptr;
unsigned long value = 0;
int i;
bfd_reloc_code_real_type reloc_type = orig_reloc_type;
gas_assert (exprstr != NULL);
gas_assert (insn != NULL);
/* Check for relocation operators.
Change the relocation type and advance the ptr to the start of
the expression proper. */
for (i = 0; i < nios2_num_special_relocs; i++)
if (strstr (exprstr, nios2_special_reloc[i].string) != NULL)
{
reloc_type = nios2_special_reloc[i].reloc_type;
exprstr += strlen (nios2_special_reloc[i].string) + 1;
/* %lo and %hiadj have different meanings for PC-relative
expressions. */
if (pcrel)
{
if (reloc_type == BFD_RELOC_NIOS2_LO16)
reloc_type = BFD_RELOC_NIOS2_PCREL_LO;
if (reloc_type == BFD_RELOC_NIOS2_HIADJ16)
reloc_type = BFD_RELOC_NIOS2_PCREL_HA;
}
break;
}
/* No relocation allowed; we must have a constant expression. */
if (orig_reloc_type == BFD_RELOC_NONE)
{
expressionS exp;
/* Parse the expression string. */
saved_line_ptr = input_line_pointer;
input_line_pointer = (char *) exprstr;
expression (&exp);
input_line_pointer = saved_line_ptr;
/* If we don't have a constant, give an error. */
if (reloc_type != orig_reloc_type || exp.X_op != O_constant)
as_bad (_("expression must be constant"));
else
value = exp.X_add_number;
return (unsigned long) value;
}
/* We potentially have a relocation. */
reloc = nios2_insn_reloc_new (reloc_type, pcrel);
reloc->reloc_next = insn->insn_reloc;
insn->insn_reloc = reloc;
/* Parse the expression string. */
saved_line_ptr = input_line_pointer;
input_line_pointer = (char *) exprstr;
expression (&reloc->reloc_expression);
input_line_pointer = saved_line_ptr;
/* This is redundant as the fixup will put this into
the instruction, but it is included here so that
self-test mode (-r) works. */
if (nios2_mode == NIOS2_MODE_TEST
&& reloc->reloc_expression.X_op == O_constant)
value = reloc->reloc_expression.X_add_number;
return (unsigned long) value;
}
/* Encode a 3-bit register number, giving an error if this is not possible. */
static unsigned int
nios2_assemble_reg3 (const char *token)
{
struct nios2_reg *reg = nios2_parse_reg (token, REG_3BIT);
int j;
if (reg == NULL)
return 0;
for (j = 0; j < nios2_num_r2_reg3_mappings; j++)
if (nios2_r2_reg3_mappings[j] == reg->index)
return j;
/* Should never get here if we passed validation. */
as_bad (_("invalid register %s"), token);
return 0;
}
/* Argument assemble functions. */
/* Control register index. */
static void
nios2_assemble_arg_c (const char *token, nios2_insn_infoS *insn)
{
struct nios2_reg *reg = nios2_parse_reg (token, REG_CONTROL);
const struct nios2_opcode *op = insn->insn_nios2_opcode;
if (reg == NULL)
return;
switch (op->format)
{
case iw_r_type:
insn->insn_code |= SET_IW_R_IMM5 (reg->index);
break;
case iw_F3X6L5_type:
insn->insn_code |= SET_IW_F3X6L5_IMM5 (reg->index);
break;
default:
bad_opcode (op);
}
}
/* Destination register. */
static void
nios2_assemble_arg_d (const char *token, nios2_insn_infoS *insn)
{
const struct nios2_opcode *op = insn->insn_nios2_opcode;
unsigned long regtype = REG_NORMAL;
struct nios2_reg *reg;
if (op->format == iw_custom_type || op->format == iw_F3X8_type)
regtype |= REG_COPROCESSOR;
reg = nios2_parse_reg (token, regtype);
if (reg == NULL)
return;
switch (op->format)
{
case iw_r_type:
insn->insn_code |= SET_IW_R_C (reg->index);
break;
case iw_custom_type:
insn->insn_code |= SET_IW_CUSTOM_C (reg->index);
if (reg->regtype & REG_COPROCESSOR)
insn->insn_code |= SET_IW_CUSTOM_READC (0);
else
insn->insn_code |= SET_IW_CUSTOM_READC (1);
break;
case iw_F3X6L5_type:
case iw_F3X6_type:
insn->insn_code |= SET_IW_F3X6L5_C (reg->index);
break;
case iw_F3X8_type:
insn->insn_code |= SET_IW_F3X8_C (reg->index);
if (reg->regtype & REG_COPROCESSOR)
insn->insn_code |= SET_IW_F3X8_READC (0);
else
insn->insn_code |= SET_IW_F3X8_READC (1);
break;
case iw_F2_type:
insn->insn_code |= SET_IW_F2_B (reg->index);
break;
default:
bad_opcode (op);
}
}
/* Source register 1. */
static void
nios2_assemble_arg_s (const char *token, nios2_insn_infoS *insn)
{
const struct nios2_opcode *op = insn->insn_nios2_opcode;
unsigned long regtype = REG_NORMAL;
struct nios2_reg *reg;
if (op->format == iw_custom_type || op->format == iw_F3X8_type)
regtype |= REG_COPROCESSOR;
reg = nios2_parse_reg (token, regtype);
if (reg == NULL)
return;
switch (op->format)
{
case iw_r_type:
if (op->match == MATCH_R1_JMP && reg->index == 31)
as_bad (_("r31 cannot be used with jmp; use ret instead"));
insn->insn_code |= SET_IW_R_A (reg->index);
break;
case iw_i_type:
insn->insn_code |= SET_IW_I_A (reg->index);
break;
case iw_custom_type:
insn->insn_code |= SET_IW_CUSTOM_A (reg->index);
if (reg->regtype & REG_COPROCESSOR)
insn->insn_code |= SET_IW_CUSTOM_READA (0);
else
insn->insn_code |= SET_IW_CUSTOM_READA (1);
break;
case iw_F2I16_type:
insn->insn_code |= SET_IW_F2I16_A (reg->index);
break;
case iw_F2X4I12_type:
insn->insn_code |= SET_IW_F2X4I12_A (reg->index);
break;
case iw_F1X4I12_type:
insn->insn_code |= SET_IW_F1X4I12_A (reg->index);
break;
case iw_F1X4L17_type:
insn->insn_code |= SET_IW_F1X4L17_A (reg->index);
break;
case iw_F3X6L5_type:
case iw_F3X6_type:
if (op->match == MATCH_R2_JMP && reg->index == 31)
as_bad (_("r31 cannot be used with jmp; use ret instead"));
insn->insn_code |= SET_IW_F3X6L5_A (reg->index);
break;
case iw_F2X6L10_type:
insn->insn_code |= SET_IW_F2X6L10_A (reg->index);
break;
case iw_F3X8_type:
insn->insn_code |= SET_IW_F3X8_A (reg->index);
if (reg->regtype & REG_COPROCESSOR)
insn->insn_code |= SET_IW_F3X8_READA (0);
else
insn->insn_code |= SET_IW_F3X8_READA (1);
break;
case iw_F1X1_type:
if (op->match == MATCH_R2_JMPR_N && reg->index == 31)
as_bad (_("r31 cannot be used with jmpr.n; use ret.n instead"));
insn->insn_code |= SET_IW_F1X1_A (reg->index);
break;
case iw_F1I5_type:
/* Implicit stack pointer reference. */
if (reg->index != 27)
as_bad (_("invalid register %s"), token);
break;
case iw_F2_type:
insn->insn_code |= SET_IW_F2_A (reg->index);
break;
default:
bad_opcode (op);
}
}
/* Source register 2. */
static void
nios2_assemble_arg_t (const char *token, nios2_insn_infoS *insn)
{
const struct nios2_opcode *op = insn->insn_nios2_opcode;
unsigned long regtype = REG_NORMAL;
struct nios2_reg *reg;
if (op->format == iw_custom_type || op->format == iw_F3X8_type)
regtype |= REG_COPROCESSOR;
reg = nios2_parse_reg (token, regtype);
if (reg == NULL)
return;
switch (op->format)
{
case iw_r_type:
insn->insn_code |= SET_IW_R_B (reg->index);
break;
case iw_i_type:
insn->insn_code |= SET_IW_I_B (reg->index);
break;
case iw_custom_type:
insn->insn_code |= SET_IW_CUSTOM_B (reg->index);
if (reg->regtype & REG_COPROCESSOR)
insn->insn_code |= SET_IW_CUSTOM_READB (0);
else
insn->insn_code |= SET_IW_CUSTOM_READB (1);
break;
case iw_F2I16_type:
insn->insn_code |= SET_IW_F2I16_B (reg->index);
break;
case iw_F2X4I12_type:
insn->insn_code |= SET_IW_F2X4I12_B (reg->index);
break;
case iw_F3X6L5_type:
case iw_F3X6_type:
insn->insn_code |= SET_IW_F3X6L5_B (reg->index);
break;
case iw_F2X6L10_type:
insn->insn_code |= SET_IW_F2X6L10_B (reg->index);
break;
case iw_F3X8_type:
insn->insn_code |= SET_IW_F3X8_B (reg->index);
if (reg->regtype & REG_COPROCESSOR)
insn->insn_code |= SET_IW_F3X8_READB (0);
else
insn->insn_code |= SET_IW_F3X8_READB (1);
break;
case iw_F1I5_type:
insn->insn_code |= SET_IW_F1I5_B (reg->index);
break;
case iw_F2_type:
insn->insn_code |= SET_IW_F2_B (reg->index);
break;
case iw_T1X1I6_type:
/* Implicit zero register reference. */
if (reg->index != 0)
as_bad (_("invalid register %s"), token);
break;
default:
bad_opcode (op);
}
}
/* Destination register w/3-bit encoding. */
static void
nios2_assemble_arg_D (const char *token, nios2_insn_infoS *insn)
{
const struct nios2_opcode *op = insn->insn_nios2_opcode;
int reg = nios2_assemble_reg3 (token);
switch (op->format)
{
case iw_T1I7_type:
insn->insn_code |= SET_IW_T1I7_A3 (reg);
break;
case iw_T2X1L3_type:
insn->insn_code |= SET_IW_T2X1L3_B3 (reg);
break;
case iw_T2X1I3_type:
insn->insn_code |= SET_IW_T2X1I3_B3 (reg);
break;
case iw_T3X1_type:
insn->insn_code |= SET_IW_T3X1_C3 (reg);
break;
case iw_T2X3_type:
/* Some instructions using this encoding take 3 register arguments,
requiring the destination register to be the same as the first
source register. */
if (op->num_args == 3)
insn->insn_code |= SET_IW_T2X3_A3 (reg);
else
insn->insn_code |= SET_IW_T2X3_B3 (reg);
break;
default:
bad_opcode (op);
}
}
/* Source register w/3-bit encoding. */
static void
nios2_assemble_arg_S (const char *token, nios2_insn_infoS *insn)
{
const struct nios2_opcode *op = insn->insn_nios2_opcode;
int reg = nios2_assemble_reg3 (token);
switch (op->format)
{
case iw_T1I7_type:
insn->insn_code |= SET_IW_T1I7_A3 (reg);
break;
case iw_T2I4_type:
insn->insn_code |= SET_IW_T2I4_A3 (reg);
break;
case iw_T2X1L3_type:
insn->insn_code |= SET_IW_T2X1L3_A3 (reg);
break;
case iw_T2X1I3_type:
insn->insn_code |= SET_IW_T2X1I3_A3 (reg);
break;
case iw_T3X1_type:
insn->insn_code |= SET_IW_T3X1_A3 (reg);
break;
case iw_T2X3_type:
/* Some instructions using this encoding take 3 register arguments,
requiring the destination register to be the same as the first
source register. */
if (op->num_args == 3)
{
int dreg = GET_IW_T2X3_A3 (insn->insn_code);
if (dreg != reg)
as_bad ("source and destination registers must be the same");
}
else
insn->insn_code |= SET_IW_T2X3_A3 (reg);
break;
case iw_T1X1I6_type:
insn->insn_code |= SET_IW_T1X1I6_A3 (reg);
break;
default:
bad_opcode (op);
}
}
/* Source register 2 w/3-bit encoding. */
static void
nios2_assemble_arg_T (const char *token, nios2_insn_infoS *insn)
{
const struct nios2_opcode *op = insn->insn_nios2_opcode;
int reg = nios2_assemble_reg3 (token);
switch (op->format)
{
case iw_T2I4_type:
insn->insn_code |= SET_IW_T2I4_B3 (reg);
break;
case iw_T3X1_type:
insn->insn_code |= SET_IW_T3X1_B3 (reg);
break;
case iw_T2X3_type:
insn->insn_code |= SET_IW_T2X3_B3 (reg);
break;
default:
bad_opcode (op);
}
}
/* 16-bit signed immediate. */
static void
nios2_assemble_arg_i (const char *token, nios2_insn_infoS *insn)
{
const struct nios2_opcode *op = insn->insn_nios2_opcode;
unsigned int val;
switch (op->format)
{
case iw_i_type:
val = nios2_assemble_expression (token, insn,
BFD_RELOC_NIOS2_S16, 0);
insn->constant_bits |= SET_IW_I_IMM16 (val);
break;
case iw_F2I16_type:
val = nios2_assemble_expression (token, insn,
BFD_RELOC_NIOS2_S16, 0);
insn->constant_bits |= SET_IW_F2I16_IMM16 (val);
break;
default:
bad_opcode (op);
}
}
/* 12-bit signed immediate. */
static void
nios2_assemble_arg_I (const char *token, nios2_insn_infoS *insn)
{
const struct nios2_opcode *op = insn->insn_nios2_opcode;
unsigned int val;
switch (op->format)
{
case iw_F2X4I12_type:
val = nios2_assemble_expression (token, insn,
BFD_RELOC_NIOS2_R2_S12, 0);
insn->constant_bits |= SET_IW_F2X4I12_IMM12 (val);
break;
case iw_F1X4I12_type:
val = nios2_assemble_expression (token, insn,
BFD_RELOC_NIOS2_R2_S12, 0);
insn->constant_bits |= SET_IW_F2X4I12_IMM12 (val);
break;
default:
bad_opcode (op);
}
}
/* 16-bit unsigned immediate. */
static void
nios2_assemble_arg_u (const char *token, nios2_insn_infoS *insn)
{
const struct nios2_opcode *op = insn->insn_nios2_opcode;
unsigned int val;
switch (op->format)
{
case iw_i_type:
val = nios2_assemble_expression (token, insn,
BFD_RELOC_NIOS2_U16, 0);
insn->constant_bits |= SET_IW_I_IMM16 (val);
break;
case iw_F2I16_type:
val = nios2_assemble_expression (token, insn,
BFD_RELOC_NIOS2_U16, 0);
insn->constant_bits |= SET_IW_F2I16_IMM16 (val);
break;
default:
bad_opcode (op);
}
}
/* 7-bit unsigned immediate with 2-bit shift. */
static void
nios2_assemble_arg_U (const char *token, nios2_insn_infoS *insn)
{
const struct nios2_opcode *op = insn->insn_nios2_opcode;
unsigned int val;
switch (op->format)
{
case iw_T1I7_type:
val = nios2_assemble_expression (token, insn,
BFD_RELOC_NIOS2_R2_T1I7_2, 0);
insn->constant_bits |= SET_IW_T1I7_IMM7 (val >> 2);
break;
case iw_X1I7_type:
val = nios2_assemble_expression (token, insn,
BFD_RELOC_NIOS2_R2_X1I7_2, 0);
insn->constant_bits |= SET_IW_X1I7_IMM7 (val >> 2);
break;
default:
bad_opcode (op);
}
}
/* 5-bit unsigned immediate with 2-bit shift. */
static void
nios2_assemble_arg_V (const char *token, nios2_insn_infoS *insn)
{
const struct nios2_opcode *op = insn->insn_nios2_opcode;
unsigned int val;
switch (op->format)
{
case iw_F1I5_type:
val = nios2_assemble_expression (token, insn,
BFD_RELOC_NIOS2_R2_F1I5_2, 0);
insn->constant_bits |= SET_IW_F1I5_IMM5 (val >> 2);
break;
default:
bad_opcode (op);
}
}
/* 4-bit unsigned immediate with 2-bit shift. */
static void
nios2_assemble_arg_W (const char *token, nios2_insn_infoS *insn)
{
const struct nios2_opcode *op = insn->insn_nios2_opcode;
unsigned int val;
switch (op->format)
{
case iw_T2I4_type:
val = nios2_assemble_expression (token, insn,
BFD_RELOC_NIOS2_R2_T2I4_2, 0);
insn->constant_bits |= SET_IW_T2I4_IMM4 (val >> 2);
break;
case iw_L5I4X1_type:
/* This argument is optional for push.n/pop.n, and defaults to
zero if unspecified. */
if (token == NULL)
return;
val = nios2_assemble_expression (token, insn,
BFD_RELOC_NIOS2_R2_L5I4X1, 0);
insn->constant_bits |= SET_IW_L5I4X1_IMM4 (val >> 2);
break;
default:
bad_opcode (op);
}
}
/* 4-bit unsigned immediate with 1-bit shift. */
static void
nios2_assemble_arg_X (const char *token, nios2_insn_infoS *insn)
{
const struct nios2_opcode *op = insn->insn_nios2_opcode;
unsigned int val;
switch (op->format)
{
case iw_T2I4_type:
val = nios2_assemble_expression (token, insn,
BFD_RELOC_NIOS2_R2_T2I4_1, 0);
insn->constant_bits |= SET_IW_T2I4_IMM4 (val >> 1);
break;
default:
bad_opcode (op);
}
}
/* 4-bit unsigned immediate without shift. */
static void
nios2_assemble_arg_Y (const char *token, nios2_insn_infoS *insn)
{
const struct nios2_opcode *op = insn->insn_nios2_opcode;
unsigned int val;
switch (op->format)
{
case iw_T2I4_type:
val = nios2_assemble_expression (token, insn,
BFD_RELOC_NIOS2_R2_T2I4, 0);
insn->constant_bits |= SET_IW_T2I4_IMM4 (val);
break;
default:
bad_opcode (op);
}
}
/* 16-bit signed immediate address offset. */
static void
nios2_assemble_arg_o (const char *token, nios2_insn_infoS *insn)
{
const struct nios2_opcode *op = insn->insn_nios2_opcode;
unsigned int val;
switch (op->format)
{
case iw_i_type:
val = nios2_assemble_expression (token, insn,
BFD_RELOC_16_PCREL, 1);
insn->constant_bits |= SET_IW_I_IMM16 (val);
break;
case iw_F2I16_type:
val = nios2_assemble_expression (token, insn,
BFD_RELOC_16_PCREL, 1);
insn->constant_bits |= SET_IW_F2I16_IMM16 (val);
break;
default:
bad_opcode (op);
}
}
/* 10-bit signed address offset with 1-bit shift. */
static void
nios2_assemble_arg_O (const char *token, nios2_insn_infoS *insn)
{
const struct nios2_opcode *op = insn->insn_nios2_opcode;
unsigned int val;
switch (op->format)
{
case iw_I10_type:
val = nios2_assemble_expression (token, insn,
BFD_RELOC_NIOS2_R2_I10_1_PCREL, 1);
insn->constant_bits |= SET_IW_I10_IMM10 (val >> 1);
break;
default:
bad_opcode (op);
}
}
/* 7-bit signed address offset with 1-bit shift. */
static void
nios2_assemble_arg_P (const char *token, nios2_insn_infoS *insn)
{
const struct nios2_opcode *op = insn->insn_nios2_opcode;
unsigned int val;
switch (op->format)
{
case iw_T1I7_type:
val = nios2_assemble_expression (token, insn,
BFD_RELOC_NIOS2_R2_T1I7_1_PCREL, 1);
insn->constant_bits |= SET_IW_T1I7_IMM7 (val >> 1);
break;
default:
bad_opcode (op);
}
}
/* 5-bit unsigned immediate. */
static void
nios2_assemble_arg_j (const char *token, nios2_insn_infoS *insn)
{
const struct nios2_opcode *op = insn->insn_nios2_opcode;
unsigned int val;
switch (op->format)
{
case iw_r_type:
val = nios2_assemble_expression (token, insn,
BFD_RELOC_NIOS2_IMM5, 0);
insn->constant_bits |= SET_IW_R_IMM5 (val);
break;
case iw_F3X6L5_type:
if (op->match == MATCH_R2_ENI)
/* Value must be constant 0 or 1. */
{
val = nios2_assemble_expression (token, insn, BFD_RELOC_NONE, 0);
if (val != 0 && val != 1)
as_bad ("invalid eni argument %u", val);
insn->insn_code |= SET_IW_F3X6L5_IMM5 (val);
}
else
{
val = nios2_assemble_expression (token, insn,
BFD_RELOC_NIOS2_IMM5, 0);
insn->constant_bits |= SET_IW_F3X6L5_IMM5 (val);
}
break;
case iw_F2X6L10_type:
/* Only constant expression without relocation permitted for
bit position. */
val = nios2_assemble_expression (token, insn, BFD_RELOC_NONE, 0);
if (val > 31)
as_bad ("invalid bit position %u", val);
insn->insn_code |= SET_IW_F2X6L10_MSB (val);
break;
case iw_X2L5_type:
val = nios2_assemble_expression (token, insn,
BFD_RELOC_NIOS2_R2_X2L5, 0);
insn->constant_bits |= SET_IW_X2L5_IMM5 (val);
break;
default:
bad_opcode (op);
}
}
/* Second 5-bit unsigned immediate field. */
static void
nios2_assemble_arg_k (const char *token, nios2_insn_infoS *insn)
{
const struct nios2_opcode *op = insn->insn_nios2_opcode;
unsigned int val;
switch (op->format)
{
case iw_F2X6L10_type:
/* Only constant expression without relocation permitted for
bit position. */
val = nios2_assemble_expression (token, insn,
BFD_RELOC_NONE, 0);
if (val > 31)
as_bad ("invalid bit position %u", val);
else if (GET_IW_F2X6L10_MSB (insn->insn_code) < val)
as_bad ("MSB must be greater than or equal to LSB");
insn->insn_code |= SET_IW_F2X6L10_LSB (val);
break;
default:
bad_opcode (op);
}
}
/* 8-bit unsigned immediate. */
static void
nios2_assemble_arg_l (const char *token, nios2_insn_infoS *insn)
{
const struct nios2_opcode *op = insn->insn_nios2_opcode;
unsigned int val;
switch (op->format)
{
case iw_custom_type:
val = nios2_assemble_expression (token, insn,
BFD_RELOC_NIOS2_IMM8, 0);
insn->constant_bits |= SET_IW_CUSTOM_N (val);
break;
case iw_F3X8_type:
val = nios2_assemble_expression (token, insn,
BFD_RELOC_NIOS2_IMM8, 0);
insn->constant_bits |= SET_IW_F3X8_N (val);
break;
default:
bad_opcode (op);
}
}
/* 26-bit unsigned immediate. */
static void
nios2_assemble_arg_m (const char *token, nios2_insn_infoS *insn)
{
const struct nios2_opcode *op = insn->insn_nios2_opcode;
unsigned int val;
switch (op->format)
{
case iw_j_type:
val = nios2_assemble_expression (token, insn,
(nios2_as_options.noat
? BFD_RELOC_NIOS2_CALL26_NOAT
: BFD_RELOC_NIOS2_CALL26),
0);
insn->constant_bits |= SET_IW_J_IMM26 (val);
break;
case iw_L26_type:
val = nios2_assemble_expression (token, insn,
(nios2_as_options.noat
? BFD_RELOC_NIOS2_CALL26_NOAT
: BFD_RELOC_NIOS2_CALL26),
0);
insn->constant_bits |= SET_IW_L26_IMM26 (val);
break;
default:
bad_opcode (op);
}
}
/* 6-bit unsigned immediate with no shifting. */
static void
nios2_assemble_arg_M (const char *token, nios2_insn_infoS *insn)
{
const struct nios2_opcode *op = insn->insn_nios2_opcode;
unsigned int val;
switch (op->format)
{
case iw_T1X1I6_type:
val = nios2_assemble_expression (token, insn,
BFD_RELOC_NIOS2_R2_T1X1I6, 0);
insn->constant_bits |= SET_IW_T1X1I6_IMM6 (val);
break;
default:
bad_opcode (op);
}
}
/* 6-bit unsigned immediate with 2-bit shift. */
static void
nios2_assemble_arg_N (const char *token, nios2_insn_infoS *insn)
{
const struct nios2_opcode *op = insn->insn_nios2_opcode;
unsigned int val;
switch (op->format)
{
case iw_T1X1I6_type:
val = nios2_assemble_expression (token, insn,
BFD_RELOC_NIOS2_R2_T1X1I6_2, 0);
insn->constant_bits |= SET_IW_T1X1I6_IMM6 (val >> 2);
break;
default:
bad_opcode (op);
}
}
/* Encoded enumeration for addi.n/subi.n. */
static void
nios2_assemble_arg_e (const char *token, nios2_insn_infoS *insn)
{
const struct nios2_opcode *op = insn->insn_nios2_opcode;
unsigned int val;
int i;
switch (op->format)
{
case iw_T2X1I3_type:
val = nios2_assemble_expression (token, insn, BFD_RELOC_NONE, 0);
for (i = 0; i < nios2_num_r2_asi_n_mappings; i++)
if (val == nios2_r2_asi_n_mappings[i])
break;
if (i == nios2_num_r2_asi_n_mappings)
{
as_bad (_("Invalid constant operand %s"), token);
return;
}
insn->insn_code |= SET_IW_T2X1I3_IMM3 ((unsigned)i);
break;
default:
bad_opcode (op);
}
}
/* Encoded enumeration for slli.n/srli.n. */
static void
nios2_assemble_arg_f (const char *token, nios2_insn_infoS *insn)
{
const struct nios2_opcode *op = insn->insn_nios2_opcode;
unsigned int val;
int i;
switch (op->format)
{
case iw_T2X1L3_type:
val = nios2_assemble_expression (token, insn, BFD_RELOC_NONE, 0);
for (i = 0; i < nios2_num_r2_shi_n_mappings; i++)
if (val == nios2_r2_shi_n_mappings[i])
break;
if (i == nios2_num_r2_shi_n_mappings)
{
as_bad (_("Invalid constant operand %s"), token);
return;
}
insn->insn_code |= SET_IW_T2X1L3_SHAMT ((unsigned)i);
break;
default:
bad_opcode (op);
}
}
/* Encoded enumeration for andi.n. */
static void
nios2_assemble_arg_g (const char *token, nios2_insn_infoS *insn)
{
const struct nios2_opcode *op = insn->insn_nios2_opcode;
unsigned int val;
int i;
switch (op->format)
{
case iw_T2I4_type:
val = nios2_assemble_expression (token, insn, BFD_RELOC_NONE, 0);
for (i = 0; i < nios2_num_r2_andi_n_mappings; i++)
if (val == nios2_r2_andi_n_mappings[i])
break;
if (i == nios2_num_r2_andi_n_mappings)
{
as_bad (_("Invalid constant operand %s"), token);
return;
}
insn->insn_code |= SET_IW_T2I4_IMM4 ((unsigned)i);
break;
default:
bad_opcode (op);
}
}
/* Encoded enumeration for movi.n. */
static void
nios2_assemble_arg_h (const char *token, nios2_insn_infoS *insn)
{
const struct nios2_opcode *op = insn->insn_nios2_opcode;
unsigned int val;
int i;
switch (op->format)
{
case iw_T1I7_type:
val = nios2_assemble_expression (token, insn, BFD_RELOC_NONE, 0);
i = (signed) val;
if ((signed) i == -1)
val = 127;
else if (i == -2)
val = 126;
else if (i == 0xff)
val = 125;
else if (i < 0 || i > 125)
{
as_bad (_("Invalid constant operand %s"), token);
return;
}
insn->insn_code |= SET_IW_T1I7_IMM7 (val);
break;
default:
bad_opcode (op);
}
}
/* Encoded REGMASK for ldwm/stwm or push.n/pop.n. */
static void
nios2_assemble_arg_R (const char *token, nios2_insn_infoS *insn)
{
const struct nios2_opcode *op = insn->insn_nios2_opcode;
unsigned long mask;
char *buf = strdup (token);
unsigned long reglist = nios2_parse_reglist (buf, op);
free (buf);
if (reglist == 0)
return;
switch (op->format)
{
case iw_F1X4L17_type:
/* Encoding for ldwm/stwm. */
if (reglist & 0x00003ffc)
mask = reglist >> 2;
else
{
insn->insn_code |= SET_IW_F1X4L17_RS (1);
mask = (reglist & 0x00ffc000) >> 14;
if (reglist & (1 << 28))
mask |= 1 << 10;
if (reglist & (1u << 31))
mask |= 1 << 11;
}
insn->insn_code |= SET_IW_F1X4L17_REGMASK (mask);
break;
case iw_L5I4X1_type:
/* Encoding for push.n/pop.n. */
if (reglist & (1 << 28))
insn->insn_code |= SET_IW_L5I4X1_FP (1);
mask = reglist & 0x00ff0000;
if (mask)
{
int i;
for (i = 0; i < nios2_num_r2_reg_range_mappings; i++)
if (nios2_r2_reg_range_mappings[i] == mask)
break;
if (i == nios2_num_r2_reg_range_mappings)
{
as_bad ("invalid reglist");
return;
}
insn->insn_code |= SET_IW_L5I4X1_REGRANGE (i);
insn->insn_code |= SET_IW_L5I4X1_CS (1);
}
break;
default:
bad_opcode (op);
}
}
/* Base register for ldwm/stwm. */
static void
nios2_assemble_arg_B (const char *token, nios2_insn_infoS *insn)
{
const struct nios2_opcode *op = insn->insn_nios2_opcode;
int direction, writeback, ret;
char *str = strdup (token);
struct nios2_reg *reg
= nios2_parse_base_register (str, &direction, &writeback, &ret);
free (str);
if (!reg)
return;
switch (op->format)
{
case iw_F1X4L17_type:
/* For ldwm, check to see if the base register is already inside the
register list. */
if (op->match == MATCH_R2_LDWM
&& (nios2_reglist_mask & (1 << reg->index)))
{
as_bad ("invalid base register; %s is inside the reglist", reg->name);
return;
}
/* For stwm, ret option is not allowed. */
if (op->match == MATCH_R2_STWM && ret)
{
as_bad ("invalid option syntax");
return;
}
/* Check that the direction matches the ordering of the reglist. */
if (nios2_reglist_dir && direction != nios2_reglist_dir)
{
as_bad ("reglist order does not match increment/decrement mode");
return;
}
insn->insn_code |= SET_IW_F1X4L17_A (reg->index);
if (direction > 0)
insn->insn_code |= SET_IW_F1X4L17_ID (1);
if (writeback)
insn->insn_code |= SET_IW_F1X4L17_WB (1);
if (ret)
insn->insn_code |= SET_IW_F1X4L17_PC (1);
break;
default:
bad_opcode (op);
}
}
static void
nios2_assemble_args (nios2_insn_infoS *insn)
{
const struct nios2_opcode *op = insn->insn_nios2_opcode;
const char *argptr;
unsigned int tokidx, ntok;
/* Make sure there are enough arguments. */
ntok = (op->pinfo & NIOS2_INSN_OPTARG) ? op->num_args - 1 : op->num_args;
for (tokidx = 1; tokidx <= ntok; tokidx++)
if (insn->insn_tokens[tokidx] == NULL)
{
as_bad ("missing argument");
return;
}
for (argptr = op->args, tokidx = 1;
*argptr && insn->insn_tokens[tokidx];
argptr++)
switch (*argptr)
{
case ',':
case '(':
case ')':
break;
case 'c':
nios2_assemble_arg_c (insn->insn_tokens[tokidx++], insn);
break;
case 'd':
nios2_assemble_arg_d (insn->insn_tokens[tokidx++], insn);
break;
case 's':
nios2_assemble_arg_s (insn->insn_tokens[tokidx++], insn);
break;
case 't':
nios2_assemble_arg_t (insn->insn_tokens[tokidx++], insn);
break;
case 'D':
nios2_assemble_arg_D (insn->insn_tokens[tokidx++], insn);
break;
case 'S':
nios2_assemble_arg_S (insn->insn_tokens[tokidx++], insn);
break;
case 'T':
nios2_assemble_arg_T (insn->insn_tokens[tokidx++], insn);
break;
case 'i':
nios2_assemble_arg_i (insn->insn_tokens[tokidx++], insn);
break;
case 'I':
nios2_assemble_arg_I (insn->insn_tokens[tokidx++], insn);
break;
case 'u':
nios2_assemble_arg_u (insn->insn_tokens[tokidx++], insn);
break;
case 'U':
nios2_assemble_arg_U (insn->insn_tokens[tokidx++], insn);
break;
case 'V':
nios2_assemble_arg_V (insn->insn_tokens[tokidx++], insn);
break;
case 'W':
nios2_assemble_arg_W (insn->insn_tokens[tokidx++], insn);
break;
case 'X':
nios2_assemble_arg_X (insn->insn_tokens[tokidx++], insn);
break;
case 'Y':
nios2_assemble_arg_Y (insn->insn_tokens[tokidx++], insn);
break;
case 'o':
nios2_assemble_arg_o (insn->insn_tokens[tokidx++], insn);
break;
case 'O':
nios2_assemble_arg_O (insn->insn_tokens[tokidx++], insn);
break;
case 'P':
nios2_assemble_arg_P (insn->insn_tokens[tokidx++], insn);
break;
case 'j':
nios2_assemble_arg_j (insn->insn_tokens[tokidx++], insn);
break;
case 'k':
nios2_assemble_arg_k (insn->insn_tokens[tokidx++], insn);
break;
case 'l':
nios2_assemble_arg_l (insn->insn_tokens[tokidx++], insn);
break;
case 'm':
nios2_assemble_arg_m (insn->insn_tokens[tokidx++], insn);
break;
case 'M':
nios2_assemble_arg_M (insn->insn_tokens[tokidx++], insn);
break;
case 'N':
nios2_assemble_arg_N (insn->insn_tokens[tokidx++], insn);
break;
case 'e':
nios2_assemble_arg_e (insn->insn_tokens[tokidx++], insn);
break;
case 'f':
nios2_assemble_arg_f (insn->insn_tokens[tokidx++], insn);
break;
case 'g':
nios2_assemble_arg_g (insn->insn_tokens[tokidx++], insn);
break;
case 'h':
nios2_assemble_arg_h (insn->insn_tokens[tokidx++], insn);
break;
case 'R':
nios2_assemble_arg_R (insn->insn_tokens[tokidx++], insn);
break;
case 'B':
nios2_assemble_arg_B (insn->insn_tokens[tokidx++], insn);
break;
default:
bad_opcode (op);
break;
}
/* Perform argument checking. */
nios2_check_assembly (insn->insn_code | insn->constant_bits,
insn->insn_tokens[tokidx]);
}
/* The function consume_arg takes a pointer into a string
of instruction tokens (args) and a pointer into a string
representing the expected sequence of tokens and separators.
It checks whether the first argument in argstr is of the
expected type, throwing an error if it is not, and returns
the pointer argstr. */
static char *
nios2_consume_arg (char *argstr, const char *parsestr)
{
char *temp;
switch (*parsestr)
{
case 'c':
case 'd':
case 's':
case 't':
case 'D':
case 'S':
case 'T':
break;
case 'i':
case 'u':
if (*argstr == '%')
{
if (nios2_special_relocation_p (argstr))
{
/* We zap the parentheses because we don't want them confused
with separators. */
temp = strchr (argstr, '(');
if (temp != NULL)
*temp = ' ';
temp = strchr (argstr, ')');
if (temp != NULL)
*temp = ' ';
}
else
as_bad (_("badly formed expression near %s"), argstr);
}
break;
case 'm':
case 'j':
case 'k':
case 'l':
case 'I':
case 'U':
case 'V':
case 'W':
case 'X':
case 'Y':
case 'O':
case 'P':
case 'e':
case 'f':
case 'g':
case 'h':
case 'M':
case 'N':
/* We can't have %hi, %lo or %hiadj here. */
if (*argstr == '%')
as_bad (_("badly formed expression near %s"), argstr);
break;
case 'R':
/* Register list for ldwm/stwm or push.n/pop.n. Replace the commas
in the list with spaces so we don't confuse them with separators. */
if (*argstr != '{')
{
as_bad ("missing '{' in register list");
break;
}
for (temp = argstr + 1; *temp; temp++)
{
if (*temp == '}')
break;
else if (*temp == ',')
*temp = ' ';
}
if (!*temp)
{
as_bad ("missing '}' in register list");
break;
}
break;
case 'B':
/* Base register and options for ldwm/stwm. This is the final argument
and consumes the rest of the argument string; replace commas
with spaces so that the token splitter doesn't think they are
separate arguments. */
for (temp = argstr; *temp; temp++)
if (*temp == ',')
*temp = ' ';
break;
case 'o':
case 'E':
break;
default:
BAD_CASE (*parsestr);
break;
}
return argstr;
}
/* The function consume_separator takes a pointer into a string
of instruction tokens (args) and a pointer into a string representing
the expected sequence of tokens and separators. It finds the first
instance of the character pointed to by separator in argstr, and
returns a pointer to the next element of argstr, which is the
following token in the sequence. */
static char *
nios2_consume_separator (char *argstr, const char *separator)
{
char *p;
/* If we have a opcode reg, expr(reg) type instruction, and
* we are separating the expr from the (reg), we find the last
* (, just in case the expression has parentheses. */
if (*separator == '(')
p = strrchr (argstr, *separator);
else
p = strchr (argstr, *separator);
if (p != NULL)
*p++ = 0;
return p;
}
/* The principal argument parsing function which takes a string argstr
representing the instruction arguments for insn, and extracts the argument
tokens matching parsestr into parsed_args. */
static void
nios2_parse_args (nios2_insn_infoS *insn, char *argstr,
const char *parsestr, char **parsed_args)
{
char *p;
char *end = NULL;
int i;
p = argstr;
i = 0;
bool terminate = false;
/* This rest of this function is it too fragile and it mostly works,
therefore special case this one. */
if (*parsestr == 0 && argstr != 0)
{
as_bad (_("too many arguments"));
parsed_args[0] = NULL;
return;
}
while (p != NULL && !terminate && i < NIOS2_MAX_INSN_TOKENS)
{
parsed_args[i] = nios2_consume_arg (p, parsestr);
++parsestr;
while (*parsestr == '(' || *parsestr == ')' || *parsestr == ',')
{
char *context = p;
p = nios2_consume_separator (p, parsestr);
/* Check for missing separators. */
if (!p && !(insn->insn_nios2_opcode->pinfo & NIOS2_INSN_OPTARG))
{
as_bad (_("expecting %c near %s"), *parsestr, context);
break;
}
++parsestr;
}
if (*parsestr == '\0')
{
/* Check that the argument string has no trailing arguments. */
end = strpbrk (p, ",");