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NetBSD/gnu/usr.bin/gas/config/tc-i960.c

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/* tc-i960.c - All the i80960-specific stuff
Copyright (C) 1989, 1990, 1991, 1992 Free Software Foundation, Inc.
This file is part of GAS.
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, 675 Mass Ave, Cambridge, MA 02139, USA. */
/* See comment on md_parse_option for 80960-specific invocation options. */
/******************************************************************************
* i80690 NOTE!!!:
* Header, symbol, and relocation info will be used on the host machine
* only -- only executable code is actually downloaded to the i80960.
* Therefore, leave all such information in host byte order.
*
* (That's a slight lie -- we DO download some header information, but
* the downloader converts the file format and corrects the byte-ordering
* of the relevant fields while doing so.)
*
***************************************************************************** */
/* There are 4 different lengths of (potentially) symbol-based displacements
* in the 80960 instruction set, each of which could require address fix-ups
* and (in the case of external symbols) emission of relocation directives:
*
* 32-bit (MEMB)
* This is a standard length for the base assembler and requires no
* special action.
*
* 13-bit (COBR)
* This is a non-standard length, but the base assembler has a hook for
* bit field address fixups: the fixS structure can point to a descriptor
* of the field, in which case our md_number_to_field() routine gets called
* to process it.
*
* I made the hook a little cleaner by having fix_new() (in the base
* assembler) return a pointer to the fixS in question. And I made it a
* little simpler by storing the field size (in this case 13) instead of
* of a pointer to another structure: 80960 displacements are ALWAYS
* stored in the low-order bits of a 4-byte word.
*
* Since the target of a COBR cannot be external, no relocation directives
* for this size displacement have to be generated. But the base assembler
* had to be modified to issue error messages if the symbol did turn out
* to be external.
*
* 24-bit (CTRL)
* Fixups are handled as for the 13-bit case (except that 24 is stored
* in the fixS).
*
* The relocation directive generated is the same as that for the 32-bit
* displacement, except that it's PC-relative (the 32-bit displacement
* never is). The i80960 version of the linker needs a mod to
* distinguish and handle the 24-bit case.
*
* 12-bit (MEMA)
* MEMA formats are always promoted to MEMB (32-bit) if the displacement
* is based on a symbol, because it could be relocated at link time.
* The only time we use the 12-bit format is if an absolute value of
* less than 4096 is specified, in which case we need neither a fixup nor
* a relocation directive.
*/
#include <stdio.h>
#include <ctype.h>
#include "as.h"
#include "obstack.h"
#include "opcode/i960.h"
extern char *input_line_pointer;
extern struct hash_control *po_hash;
extern char *next_object_file_charP;
#ifdef OBJ_COFF
const int md_reloc_size = sizeof(struct reloc);
#else /* OBJ_COFF */
const int md_reloc_size = sizeof(struct relocation_info);
#endif /* OBJ_COFF */
/***************************
* Local i80960 routines *
************************** */
static void brcnt_emit(); /* Emit branch-prediction instrumentation code */
static char * brlab_next(); /* Return next branch local label */
void brtab_emit(); /* Emit br-predict instrumentation table */
static void cobr_fmt(); /* Generate COBR instruction */
static void ctrl_fmt(); /* Generate CTRL instruction */
static char * emit(); /* Emit (internally) binary */
static int get_args(); /* Break arguments out of comma-separated list */
static void get_cdisp(); /* Handle COBR or CTRL displacement */
static char * get_ispec(); /* Find index specification string */
static int get_regnum(); /* Translate text to register number */
static int i_scan(); /* Lexical scan of instruction source */
static void mem_fmt(); /* Generate MEMA or MEMB instruction */
static void mema_to_memb(); /* Convert MEMA instruction to MEMB format */
static segT parse_expr(); /* Parse an expression */
static int parse_ldconst();/* Parse and replace a 'ldconst' pseudo-op */
static void parse_memop(); /* Parse a memory operand */
static void parse_po(); /* Parse machine-dependent pseudo-op */
static void parse_regop(); /* Parse a register operand */
static void reg_fmt(); /* Generate a REG format instruction */
void reloc_callj(); /* Relocate a 'callj' instruction */
static void relax_cobr(); /* "De-optimize" cobr into compare/branch */
static void s_leafproc(); /* Process '.leafproc' pseudo-op */
static void s_sysproc(); /* Process '.sysproc' pseudo-op */
static int shift_ok(); /* Will a 'shlo' substiture for a 'ldconst'? */
static void syntax(); /* Give syntax error */
static int targ_has_sfr(); /* Target chip supports spec-func register? */
static int targ_has_iclass();/* Target chip supports instruction set? */
/* static void unlink_sym(); */ /* Remove a symbol from the symbol list */
/* See md_parse_option() for meanings of these options */
static char norelax = 0; /* True if -norelax switch seen */
static char instrument_branches = 0; /* True if -b switch seen */
/* Characters that always start a comment.
* If the pre-processor is disabled, these aren't very useful.
*/
char comment_chars[] = "#";
/* Characters 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 comments started like this one will always work. */
char line_comment_chars[] = "";
/* Chars that can be used to separate mant from exp in floating point nums */
char EXP_CHARS[] = "eE";
/* Chars that mean this number is a floating point constant,
* as in 0f12.456 or 0d1.2345e12
*/
char FLT_CHARS[] = "fFdDtT";
/* Table used by base assembler to relax addresses based on varying length
* instructions. The fields are:
* 1) most positive reach of this state,
* 2) most negative reach of this state,
* 3) how many bytes this mode will add to the size of the current frag
* 4) which index into the table to try if we can't fit into this one.
*
* For i80960, the only application is the (de-)optimization of cobr
* instructions into separate compare and branch instructions when a 13-bit
* displacement won't hack it.
*/
const relax_typeS
md_relax_table[] = {
{0, 0, 0,0}, /* State 0 => no more relaxation possible */
{4088, -4096, 0,2}, /* State 1: conditional branch (cobr) */
{0x800000-8,-0x800000,4,0}, /* State 2: compare (reg) & branch (ctrl) */
};
/* These are the machine dependent pseudo-ops.
*
* This table describes all the machine specific pseudo-ops the assembler
* has to support. The fields are:
* pseudo-op name without dot
* function to call to execute this pseudo-op
* integer arg to pass to the function
*/
#define S_LEAFPROC 1
#define S_SYSPROC 2
const pseudo_typeS
md_pseudo_table[] = {
{ "bss", s_lcomm, 1 },
{ "extended", float_cons, 't' },
{ "leafproc", parse_po, S_LEAFPROC },
{ "sysproc", parse_po, S_SYSPROC },
{ "word", cons, 4 },
{ "quad", big_cons, 16 },
{ 0, 0, 0 }
};
/* Macros to extract info from an 'expressionS' structure 'e' */
#define adds(e) e.X_add_symbol
#define subs(e) e.X_subtract_symbol
#define offs(e) e.X_add_number
#define segs(e) e.X_seg
/* Branch-prediction bits for CTRL/COBR format opcodes */
#define BP_MASK 0x00000002 /* Mask for branch-prediction bit */
#define BP_TAKEN 0x00000000 /* Value to OR in to predict branch */
#define BP_NOT_TAKEN 0x00000002 /* Value to OR in to predict no branch */
/* Some instruction opcodes that we need explicitly */
#define BE 0x12000000
#define BG 0x11000000
#define BGE 0x13000000
#define BL 0x14000000
#define BLE 0x16000000
#define BNE 0x15000000
#define BNO 0x10000000
#define BO 0x17000000
#define CHKBIT 0x5a002700
#define CMPI 0x5a002080
#define CMPO 0x5a002000
#define B 0x08000000
#define BAL 0x0b000000
#define CALL 0x09000000
#define CALLS 0x66003800
#define RET 0x0a000000
/* These masks are used to build up a set of MEMB mode bits. */
#define A_BIT 0x0400
#define I_BIT 0x0800
#define MEMB_BIT 0x1000
#define D_BIT 0x2000
/* Mask for the only mode bit in a MEMA instruction (if set, abase reg is used) */
#define MEMA_ABASE 0x2000
/* Info from which a MEMA or MEMB format instruction can be generated */
typedef struct {
long opcode; /* (First) 32 bits of instruction */
int disp; /* 0-(none), 12- or, 32-bit displacement needed */
char *e; /* The expression in the source instruction from
* which the displacement should be determined
*/
} memS;
/* The two pieces of info we need to generate a register operand */
struct regop {
int mode; /* 0 =>local/global/spec reg; 1=> literal or fp reg */
int special; /* 0 =>not a sfr; 1=> is a sfr (not valid w/mode=0) */
int n; /* Register number or literal value */
};
/* Number and assembler mnemonic for all registers that can appear in operands */
static struct {
char *reg_name;
int reg_num;
} regnames[] = {
{ "pfp", 0 }, { "sp", 1 }, { "rip", 2 }, { "r3", 3 },
{ "r4", 4 }, { "r5", 5 }, { "r6", 6 }, { "r7", 7 },
{ "r8", 8 }, { "r9", 9 }, { "r10", 10 }, { "r11", 11 },
{ "r12", 12 }, { "r13", 13 }, { "r14", 14 }, { "r15", 15 },
{ "g0", 16 }, { "g1", 17 }, { "g2", 18 }, { "g3", 19 },
{ "g4", 20 }, { "g5", 21 }, { "g6", 22 }, { "g7", 23 },
{ "g8", 24 }, { "g9", 25 }, { "g10", 26 }, { "g11", 27 },
{ "g12", 28 }, { "g13", 29 }, { "g14", 30 }, { "fp", 31 },
/* Numbers for special-function registers are for assembler internal
* use only: they are scaled back to range [0-31] for binary output.
*/
# define SF0 32
{ "sf0", 32 }, { "sf1", 33 }, { "sf2", 34 }, { "sf3", 35 },
{ "sf4", 36 }, { "sf5", 37 }, { "sf6", 38 }, { "sf7", 39 },
{ "sf8", 40 }, { "sf9", 41 }, { "sf10",42 }, { "sf11",43 },
{ "sf12",44 }, { "sf13",45 }, { "sf14",46 }, { "sf15",47 },
{ "sf16",48 }, { "sf17",49 }, { "sf18",50 }, { "sf19",51 },
{ "sf20",52 }, { "sf21",53 }, { "sf22",54 }, { "sf23",55 },
{ "sf24",56 }, { "sf25",57 }, { "sf26",58 }, { "sf27",59 },
{ "sf28",60 }, { "sf29",61 }, { "sf30",62 }, { "sf31",63 },
/* Numbers for floating point registers are for assembler internal use
* only: they are scaled back to [0-3] for binary output.
*/
# define FP0 64
{ "fp0", 64 }, { "fp1", 65 }, { "fp2", 66 }, { "fp3", 67 },
{ NULL, 0 }, /* END OF LIST */
};
#define IS_RG_REG(n) ((0 <= (n)) && ((n) < SF0))
#define IS_SF_REG(n) ((SF0 <= (n)) && ((n) < FP0))
#define IS_FP_REG(n) ((n) >= FP0)
/* Number and assembler mnemonic for all registers that can appear as 'abase'
* (indirect addressing) registers.
*/
static struct {
char *areg_name;
int areg_num;
} aregs[] = {
{ "(pfp)", 0 }, { "(sp)", 1 }, { "(rip)", 2 }, { "(r3)", 3 },
{ "(r4)", 4 }, { "(r5)", 5 }, { "(r6)", 6 }, { "(r7)", 7 },
{ "(r8)", 8 }, { "(r9)", 9 }, { "(r10)", 10 }, { "(r11)", 11 },
{ "(r12)", 12 }, { "(r13)", 13 }, { "(r14)", 14 }, { "(r15)", 15 },
{ "(g0)", 16 }, { "(g1)", 17 }, { "(g2)", 18 }, { "(g3)", 19 },
{ "(g4)", 20 }, { "(g5)", 21 }, { "(g6)", 22 }, { "(g7)", 23 },
{ "(g8)", 24 }, { "(g9)", 25 }, { "(g10)", 26 }, { "(g11)", 27 },
{ "(g12)", 28 }, { "(g13)", 29 }, { "(g14)", 30 }, { "(fp)", 31 },
# define IPREL 32
/* for assembler internal use only: this number never appears in binary
* output.
*/
{ "(ip)", IPREL },
{ NULL, 0 }, /* END OF LIST */
};
/* Hash tables */
static struct hash_control *op_hash = NULL; /* Opcode mnemonics */
static struct hash_control *reg_hash = NULL; /* Register name hash table */
static struct hash_control *areg_hash = NULL; /* Abase register hash table */
/* Architecture for which we are assembling */
#define ARCH_ANY 0 /* Default: no architecture checking done */
#define ARCH_KA 1
#define ARCH_KB 2
#define ARCH_MC 3
#define ARCH_CA 4
int architecture = ARCH_ANY; /* Architecture requested on invocation line */
int iclasses_seen = 0; /* OR of instruction classes (I_* constants)
* for which we've actually assembled
* instructions.
*/
/* BRANCH-PREDICTION INSTRUMENTATION
*
* The following supports generation of branch-prediction instrumentation
* (turned on by -b switch). The instrumentation collects counts
* of branches taken/not-taken for later input to a utility that will
* set the branch prediction bits of the instructions in accordance with
* the behavior observed. (Note that the KX series does not have
* brach-prediction.)
*
* The instrumentation consists of:
*
* (1) before and after each conditional branch, a call to an external
* routine that increments and steps over an inline counter. The
* counter itself, initialized to 0, immediately follows the call
* instruction. For each branch, the counter following the branch
* is the number of times the branch was not taken, and the difference
* between the counters is the number of times it was taken. An
* example of an instrumented conditional branch:
*
* call BR_CNT_FUNC
* .word 0
* LBRANCH23: be label
* call BR_CNT_FUNC
* .word 0
*
* (2) a table of pointers to the instrumented branches, so that an
* external postprocessing routine can locate all of the counters.
* the table begins with a 2-word header: a pointer to the next in
* a linked list of such tables (initialized to 0); and a count
* of the number of entries in the table (exclusive of the header.
*
* Note that input source code is expected to already contain calls
* an external routine that will link the branch local table into a
* list of such tables.
*/
static int br_cnt = 0; /* Number of branches instrumented so far.
* Also used to generate unique local labels
* for each instrumented branch
*/
#define BR_LABEL_BASE "LBRANCH"
/* Basename of local labels on instrumented
* branches, to avoid conflict with compiler-
* generated local labels.
*/
#define BR_CNT_FUNC "__inc_branch"
/* Name of the external routine that will
* increment (and step over) an inline counter.
*/
#define BR_TAB_NAME "__BRANCH_TABLE__"
/* Name of the table of pointers to branches.
* A local (i.e., non-external) symbol.
*/
/*****************************************************************************
* md_begin: One-time initialization.
*
* Set up hash tables.
*
**************************************************************************** */
void
md_begin()
{
int i; /* Loop counter */
const struct i960_opcode *oP; /* Pointer into opcode table */
char *retval; /* Value returned by hash functions */
if (((op_hash = hash_new()) == 0)
|| ((reg_hash = hash_new()) == 0)
|| ((areg_hash = hash_new()) == 0)) {
as_fatal("virtual memory exceeded");
}
retval = ""; /* For some reason, the base assembler uses an empty
* string for "no error message", instead of a NULL
* pointer.
*/
for (oP=i960_opcodes; oP->name && !*retval; oP++) {
retval = hash_insert(op_hash, oP->name, oP);
}
for (i=0; regnames[i].reg_name && !*retval; i++) {
retval = hash_insert(reg_hash, regnames[i].reg_name,
&regnames[i].reg_num);
}
for (i=0; aregs[i].areg_name && !*retval; i++){
retval = hash_insert(areg_hash, aregs[i].areg_name,
&aregs[i].areg_num);
}
if (*retval) {
as_fatal("Hashing returned \"%s\".", retval);
}
} /* md_begin() */
/*****************************************************************************
* md_end: One-time final cleanup
*
* None necessary
*
**************************************************************************** */
void
md_end()
{
}
/*****************************************************************************
* md_assemble: Assemble an instruction
*
* Assumptions about the passed-in text:
* - all comments, labels removed
* - text is an instruction
* - all white space compressed to single blanks
* - all character constants have been replaced with decimal
*
**************************************************************************** */
void
md_assemble(textP)
char *textP; /* Source text of instruction */
{
char *args[4]; /* Parsed instruction text, containing NO whitespace:
* arg[0]->opcode mnemonic
* arg[1-3]->operands, with char constants
* replaced by decimal numbers
*/
int n_ops; /* Number of instruction operands */
struct i960_opcode *oP;
/* Pointer to instruction description */
int branch_predict;
/* TRUE iff opcode mnemonic included branch-prediction
* suffix (".f" or ".t")
*/
long bp_bits; /* Setting of branch-prediction bit(s) to be OR'd
* into instruction opcode of CTRL/COBR format
* instructions.
*/
int n; /* Offset of last character in opcode mnemonic */
static const char bp_error_msg[] = "branch prediction invalid on this opcode";
/* Parse instruction into opcode and operands */
memset(args, '\0', sizeof(args));
n_ops = i_scan(textP, args);
if (n_ops == -1){
return; /* Error message already issued */
}
/* Do "macro substitution" (sort of) on 'ldconst' pseudo-instruction */
if (!strcmp(args[0],"ldconst")){
n_ops = parse_ldconst(args);
if (n_ops == -1){
return;
}
}
/* Check for branch-prediction suffix on opcode mnemonic, strip it off */
n = strlen(args[0]) - 1;
branch_predict = 0;
bp_bits = 0;
if (args[0][n-1] == '.' && (args[0][n] == 't' || args[0][n] == 'f')){
/* We could check here to see if the target architecture
* supports branch prediction, but why bother? The bit
* will just be ignored by processors that don't use it.
*/
branch_predict = 1;
bp_bits = (args[0][n] == 't') ? BP_TAKEN : BP_NOT_TAKEN;
args[0][n-1] = '\0'; /* Strip suffix from opcode mnemonic */
}
/* Look up opcode mnemonic in table and check number of operands.
* Check that opcode is legal for the target architecture.
* If all looks good, assemble instruction.
*/
oP = (struct i960_opcode *) hash_find(op_hash, args[0]);
if (!oP || !targ_has_iclass(oP->iclass)) {
as_bad("invalid opcode, \"%s\".", args[0]);
} else if (n_ops != oP->num_ops) {
as_bad("improper number of operands. expecting %d, got %d", oP->num_ops, n_ops);
} else {
switch (oP->format){
case FBRA:
case CTRL:
ctrl_fmt(args[1], oP->opcode | bp_bits, oP->num_ops);
if (oP->format == FBRA){
/* Now generate a 'bno' to same arg */
ctrl_fmt(args[1], BNO | bp_bits, 1);
}
break;
case COBR:
case COJ:
cobr_fmt(args, oP->opcode | bp_bits, oP);
break;
case REG:
if (branch_predict){
as_warn(bp_error_msg);
}
reg_fmt(args, oP);
break;
case MEM1:
case MEM2:
case MEM4:
case MEM8:
case MEM12:
case MEM16:
if (branch_predict){
as_warn(bp_error_msg);
}
mem_fmt(args, oP);
break;
case CALLJ:
if (branch_predict){
as_warn(bp_error_msg);
}
/* Output opcode & set up "fixup" (relocation);
* flag relocation as 'callj' type.
*/
know(oP->num_ops == 1);
get_cdisp(args[1], "CTRL", oP->opcode, 24, 0, 1);
break;
default:
BAD_CASE(oP->format);
break;
}
}
} /* md_assemble() */
/*****************************************************************************
* md_number_to_chars: convert a number to target byte order
*
**************************************************************************** */
void
md_number_to_chars(buf, value, n)
char *buf; /* Put output here */
long value; /* The integer to be converted */
int n; /* Number of bytes to output (significant bytes
* in 'value')
*/
{
while (n--){
*buf++ = value;
value >>= 8;
}
/* XXX line number probably botched for this warning message. */
if (value != 0 && value != -1){
as_bad("Displacement too long for instruction field length.");
}
return;
} /* md_number_to_chars() */
/*****************************************************************************
* md_chars_to_number: convert from target byte order to host byte order.
*
**************************************************************************** */
int
md_chars_to_number(val, n)
unsigned char *val; /* Value in target byte order */
int n; /* Number of bytes in the input */
{
int retval;
for (retval=0; n--;){
retval <<= 8;
retval |= val[n];
}
return retval;
}
#define MAX_LITTLENUMS 6
#define LNUM_SIZE sizeof(LITTLENUM_TYPE)
/*****************************************************************************
* md_atof: convert ascii to floating point
*
* Turn a string at input_line_pointer into a floating point constant of type
* 'type', and store the appropriate bytes at *litP. The number of LITTLENUMS
* emitted is returned at 'sizeP'. An error message is returned, or a pointer
* to an empty message if OK.
*
* Note we call the i386 floating point routine, rather than complicating
* things with more files or symbolic links.
*
**************************************************************************** */
char * md_atof(type, litP, sizeP)
int type;
char *litP;
int *sizeP;
{
LITTLENUM_TYPE words[MAX_LITTLENUMS];
LITTLENUM_TYPE *wordP;
int prec;
char *t;
char *atof_ieee();
switch (type) {
case 'f':
case 'F':
prec = 2;
break;
case 'd':
case 'D':
prec = 4;
break;
case 't':
case 'T':
prec = 5;
type = 'x'; /* That's what atof_ieee() understands */
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 * LNUM_SIZE;
/* Output the LITTLENUMs in REVERSE order in accord with i80960
* word-order. (Dunno why atof_ieee doesn't do it in the right
* order in the first place -- probably because it's a hack of
* atof_m68k.)
*/
for (wordP = words + prec - 1; prec--;){
md_number_to_chars(litP, (long) (*wordP--), LNUM_SIZE);
litP += sizeof(LITTLENUM_TYPE);
}
return ""; /* Someone should teach Dean about null pointers */
}
/*****************************************************************************
* md_number_to_imm
*
**************************************************************************** */
void
md_number_to_imm(buf, val, n)
char *buf;
long val;
int n;
{
md_number_to_chars(buf, val, n);
}
/*****************************************************************************
* md_number_to_disp
*
**************************************************************************** */
void
md_number_to_disp(buf, val, n)
char *buf;
long val;
int n;
{
md_number_to_chars(buf, val, n);
}
/*****************************************************************************
* md_number_to_field:
*
* Stick a value (an address fixup) into a bit field of
* previously-generated instruction.
*
**************************************************************************** */
void
md_number_to_field(instrP, val, bfixP)
char *instrP; /* Pointer to instruction to be fixed */
long val; /* Address fixup value */
bit_fixS *bfixP; /* Description of bit field to be fixed up */
{
int numbits; /* Length of bit field to be fixed */
long instr; /* 32-bit instruction to be fixed-up */
long sign; /* 0 or -1, according to sign bit of 'val' */
/* Convert instruction back to host byte order
*/
instr = md_chars_to_number(instrP, 4);
/* Surprise! -- we stored the number of bits
* to be modified rather than a pointer to a structure.
*/
numbits = (int)bfixP;
if (numbits == 1){
/* This is a no-op, stuck here by reloc_callj() */
return;
}
know ((numbits == 13) || (numbits == 24));
/* Propagate sign bit of 'val' for the given number of bits.
* Result should be all 0 or all 1
*/
sign = val >> ((int)numbits - 1);
if (((val < 0) && (sign != -1))
|| ((val > 0) && (sign != 0))){
as_bad("Fixup of %d too large for field width of %d",
val, numbits);
} else {
/* Put bit field into instruction and write back in target
* byte order.
*/
val &= ~(-1 << (int)numbits); /* Clear unused sign bits */
instr |= val;
md_number_to_chars(instrP, instr, 4);
}
} /* md_number_to_field() */
/*****************************************************************************
* md_parse_option
* Invocation line includes a switch not recognized by the base assembler.
* See if it's a processor-specific option. For the 960, these are:
*
* -norelax:
* Conditional branch instructions that require displacements
* greater than 13 bits (or that have external targets) should
* generate errors. The default is to replace each such
* instruction with the corresponding compare (or chkbit) and
* branch instructions. Note that the Intel "j" cobr directives
* are ALWAYS "de-optimized" in this way when necessary,
* regardless of the setting of this option.
*
* -b:
* Add code to collect information about branches taken, for
* later optimization of branch prediction bits by a separate
* tool. COBR and CNTL format instructions have branch
* prediction bits (in the CX architecture); if "BR" represents
* an instruction in one of these classes, the following rep-
* resents the code generated by the assembler:
*
* call <increment routine>
* .word 0 # pre-counter
* Label: BR
* call <increment routine>
* .word 0 # post-counter
*
* A table of all such "Labels" is also generated.
*
*
* -AKA, -AKB, -AKC, -ASA, -ASB, -AMC, -ACA:
* Select the 80960 architecture. Instructions or features not
* supported by the selected architecture cause fatal errors.
* The default is to generate code for any instruction or feature
* that is supported by SOME version of the 960 (even if this
* means mixing architectures!).
*
**************************************************************************** */
int
md_parse_option(argP, cntP, vecP)
char **argP;
int *cntP;
char ***vecP;
{
char *p;
struct tabentry { char *flag; int arch; };
static struct tabentry arch_tab[] = {
"KA", ARCH_KA,
"KB", ARCH_KB,
"SA", ARCH_KA, /* Synonym for KA */
"SB", ARCH_KB, /* Synonym for KB */
"KC", ARCH_MC, /* Synonym for MC */
"MC", ARCH_MC,
"CA", ARCH_CA,
NULL, 0
};
struct tabentry *tp;
if (!strcmp(*argP,"norelax")){
norelax = 1;
} else if (**argP == 'b'){
instrument_branches = 1;
} else if (**argP == 'A'){
p = (*argP) + 1;
for (tp = arch_tab; tp->flag != NULL; tp++){
if (!strcmp(p,tp->flag)){
break;
}
}
if (tp->flag == NULL){
as_bad("unknown architecture: %s", p);
} else {
architecture = tp->arch;
}
} else {
/* Unknown option */
(*argP)++;
return 0;
}
**argP = '\0'; /* Done parsing this switch */
return 1;
}
/*****************************************************************************
* md_convert_frag:
* Called by base assembler after address relaxation is finished: modify
* variable fragments according to how much relaxation was done.
*
* If the fragment substate is still 1, a 13-bit displacement was enough
* to reach the symbol in question. Set up an address fixup, but otherwise
* leave the cobr instruction alone.
*
* If the fragment substate is 2, a 13-bit displacement was not enough.
* Replace the cobr with a two instructions (a compare and a branch).
*
**************************************************************************** */
void
md_convert_frag(headers, fragP)
object_headers *headers;
fragS * fragP;
{
fixS *fixP; /* Structure describing needed address fix */
switch (fragP->fr_subtype){
case 1:
/* LEAVE SINGLE COBR INSTRUCTION */
fixP = fix_new(fragP,
fragP->fr_opcode-fragP->fr_literal,
4,
fragP->fr_symbol,
0,
fragP->fr_offset,
1,
0);
fixP->fx_bit_fixP = (bit_fixS *) 13; /* size of bit field */
break;
case 2:
/* REPLACE COBR WITH COMPARE/BRANCH INSTRUCTIONS */
relax_cobr(fragP);
break;
default:
BAD_CASE(fragP->fr_subtype);
break;
}
}
/*****************************************************************************
* md_estimate_size_before_relax: How much does it look like *fragP will grow?
*
* Called by base assembler just before address relaxation.
* Return the amount by which the fragment will grow.
*
* Any symbol that is now undefined will not become defined; cobr's
* based on undefined symbols will have to be replaced with a compare
* instruction and a branch instruction, and the code fragment will grow
* by 4 bytes.
*
**************************************************************************** */
int
md_estimate_size_before_relax(fragP, segment_type)
register fragS *fragP;
register segT segment_type;
{
/* If symbol is undefined in this segment, go to "relaxed" state
* (compare and branch instructions instead of cobr) right now.
*/
if (S_GET_SEGMENT(fragP->fr_symbol) != segment_type) {
relax_cobr(fragP);
return 4;
}
return 0;
} /* md_estimate_size_before_relax() */
/*****************************************************************************
* md_ri_to_chars:
* This routine exists in order to overcome machine byte-order problems
* when dealing with bit-field entries in the relocation_info struct.
*
* But relocation info will be used on the host machine only (only
* executable code is actually downloaded to the i80960). Therefore,
* we leave it in host byte order.
*
**************************************************************************** */
void md_ri_to_chars(where, ri)
char *where;
struct relocation_info *ri;
{
*((struct relocation_info *) where) = *ri; /* structure assignment */
} /* md_ri_to_chars() */
#ifndef WORKING_DOT_WORD
int md_short_jump_size = 0;
int md_long_jump_size = 0;
void md_create_short_jump(ptr, from_addr, to_addr, frag, to_symbol)
char *ptr;
long from_addr;
long to_addr;
fragS *frag;
symbolS *to_symbol;
{
as_fatal("failed sanity check.");
}
void
md_create_long_jump(ptr,from_addr,to_addr,frag,to_symbol)
char *ptr;
long from_addr, to_addr;
fragS *frag;
symbolS *to_symbol;
{
as_fatal("failed sanity check.");
}
#endif
/*************************************************************
* *
* FOLLOWING ARE THE LOCAL ROUTINES, IN ALPHABETICAL ORDER *
* *
************************************************************ */
/*****************************************************************************
* brcnt_emit: Emit code to increment inline branch counter.
*
* See the comments above the declaration of 'br_cnt' for details on
* branch-prediction instrumentation.
**************************************************************************** */
static void
brcnt_emit()
{
ctrl_fmt(BR_CNT_FUNC,CALL,1);/* Emit call to "increment" routine */
emit(0); /* Emit inline counter to be incremented */
}
/*****************************************************************************
* brlab_next: generate the next branch local label
*
* See the comments above the declaration of 'br_cnt' for details on
* branch-prediction instrumentation.
**************************************************************************** */
static char *
brlab_next()
{
static char buf[20];
sprintf(buf, "%s%d", BR_LABEL_BASE, br_cnt++);
return buf;
}
/*****************************************************************************
* brtab_emit: generate the fetch-prediction branch table.
*
* See the comments above the declaration of 'br_cnt' for details on
* branch-prediction instrumentation.
*
* The code emitted here would be functionally equivalent to the following
* example assembler source.
*
* .data
* .align 2
* BR_TAB_NAME:
* .word 0 # link to next table
* .word 3 # length of table
* .word LBRANCH0 # 1st entry in table proper
* .word LBRANCH1
* .word LBRANCH2
***************************************************************************** */
void
brtab_emit()
{
int i;
char buf[20];
char *p; /* Where the binary was output to */
fixS *fixP; /*->description of deferred address fixup */
if (!instrument_branches){
return;
}
subseg_new(SEG_DATA,0); /* .data */
frag_align(2,0); /* .align 2 */
record_alignment(now_seg,2);
colon(BR_TAB_NAME); /* BR_TAB_NAME: */
emit(0); /* .word 0 #link to next table */
emit(br_cnt); /* .word n #length of table */
for (i=0; i<br_cnt; i++){
sprintf(buf, "%s%d", BR_LABEL_BASE, i);
p = emit(0);
fixP = fix_new(frag_now,
p - frag_now->fr_literal,
4,
symbol_find(buf),
0,
0,
0,
0);
fixP->fx_im_disp = 2; /* 32-bit displacement fix */
}
}
/*****************************************************************************
* cobr_fmt: generate a COBR-format instruction
*
**************************************************************************** */
static
void
cobr_fmt(arg, opcode, oP)
char *arg[]; /* arg[0]->opcode mnemonic, arg[1-3]->operands (ascii) */
long opcode; /* Opcode, with branch-prediction bits already set
* if necessary.
*/
struct i960_opcode *oP;
/*->description of instruction */
{
long instr; /* 32-bit instruction */
struct regop regop; /* Description of register operand */
int n; /* Number of operands */
int var_frag; /* 1 if varying length code fragment should
* be emitted; 0 if an address fix
* should be emitted.
*/
instr = opcode;
n = oP->num_ops;
if (n >= 1) {
/* First operand (if any) of a COBR is always a register
* operand. Parse it.
*/
parse_regop(&regop, arg[1], oP->operand[0]);
instr |= (regop.n << 19) | (regop.mode << 13);
}
if (n >= 2) {
/* Second operand (if any) of a COBR is always a register
* operand. Parse it.
*/
parse_regop(&regop, arg[2], oP->operand[1]);
instr |= (regop.n << 14) | regop.special;
}
if (n < 3){
emit(instr);
} else {
if (instrument_branches){
brcnt_emit();
colon(brlab_next());
}
/* A third operand to a COBR is always a displacement.
* Parse it; if it's relaxable (a cobr "j" directive, or any
* cobr other than bbs/bbc when the "-norelax" option is not in
* use) set up a variable code fragment; otherwise set up an
* address fix.
*/
var_frag = !norelax || (oP->format == COJ); /* TRUE or FALSE */
get_cdisp(arg[3], "COBR", instr, 13, var_frag, 0);
if (instrument_branches){
brcnt_emit();
}
}
} /* cobr_fmt() */
/*****************************************************************************
* ctrl_fmt: generate a CTRL-format instruction
*
**************************************************************************** */
static
void
ctrl_fmt(targP, opcode, num_ops)
char *targP; /* Pointer to text of lone operand (if any) */
long opcode; /* Template of instruction */
int num_ops; /* Number of operands */
{
int instrument; /* TRUE iff we should add instrumentation to track
* how often the branch is taken
*/
if (num_ops == 0){
emit(opcode); /* Output opcode */
} else {
instrument = instrument_branches && (opcode != CALL)
&& (opcode != B) && (opcode != RET) && (opcode != BAL);
if (instrument){
brcnt_emit();
colon(brlab_next());
}
/* The operand MUST be an ip-relative displacment. Parse it
* and set up address fix for the instruction we just output.
*/
get_cdisp(targP, "CTRL", opcode, 24, 0, 0);
if (instrument){
brcnt_emit();
}
}
}
/*****************************************************************************
* emit: output instruction binary
*
* Output instruction binary, in target byte order, 4 bytes at a time.
* Return pointer to where it was placed.
*
**************************************************************************** */
static
char *
emit(instr)
long instr; /* Word to be output, host byte order */
{
char *toP; /* Where to output it */
toP = frag_more(4); /* Allocate storage */
md_number_to_chars(toP, instr, 4); /* Convert to target byte order */
return toP;
}
/*****************************************************************************
* get_args: break individual arguments out of comma-separated list
*
* Input assumptions:
* - all comments and labels have been removed
* - all strings of whitespace have been collapsed to a single blank.
* - all character constants ('x') have been replaced with decimal
*
* Output:
* args[0] is untouched. args[1] points to first operand, etc. All args:
* - are NULL-terminated
* - contain no whitespace
*
* Return value:
* Number of operands (0,1,2, or 3) or -1 on error.
*
**************************************************************************** */
static int get_args(p, args)
register char *p; /* Pointer to comma-separated operands; MUCKED BY US */
char *args[]; /* Output arg: pointers to operands placed in args[1-3].
* MUST ACCOMMODATE 4 ENTRIES (args[0-3]).
*/
{
register int n; /* Number of operands */
register char *to;
/* char buf[4]; */
/* int len; */
/* Skip lead white space */
while (*p == ' '){
p++;
}
if (*p == '\0'){
return 0;
}
n = 1;
args[1] = p;
/* Squeze blanks out by moving non-blanks toward start of string.
* Isolate operands, whenever comma is found.
*/
to = p;
while (*p != '\0'){
if (*p == ' '){
p++;
} else if (*p == ','){
/* Start of operand */
if (n == 3){
as_bad("too many operands");
return -1;
}
*to++ = '\0'; /* Terminate argument */
args[++n] = to; /* Start next argument */
p++;
} else {
*to++ = *p++;
}
}
*to = '\0';
return n;
}
/*****************************************************************************
* get_cdisp: handle displacement for a COBR or CTRL instruction.
*
* Parse displacement for a COBR or CTRL instruction.
*
* If successful, output the instruction opcode and set up for it,
* depending on the arg 'var_frag', either:
* o an address fixup to be done when all symbol values are known, or
* o a varying length code fragment, with address fixup info. This
* will be done for cobr instructions that may have to be relaxed
* in to compare/branch instructions (8 bytes) if the final address
* displacement is greater than 13 bits.
*
**************************************************************************** */
static
void
get_cdisp(dispP, ifmtP, instr, numbits, var_frag, callj)
char *dispP; /*->displacement as specified in source instruction */
char *ifmtP; /*->"COBR" or "CTRL" (for use in error message) */
long instr; /* Instruction needing the displacement */
int numbits; /* # bits of displacement (13 for COBR, 24 for CTRL) */
int var_frag; /* 1 if varying length code fragment should be emitted;
* 0 if an address fix should be emitted.
*/
int callj; /* 1 if callj relocation should be done; else 0 */
{
expressionS e; /* Parsed expression */
fixS *fixP; /* Structure describing needed address fix */
char *outP; /* Where instruction binary is output to */
fixP = NULL;
switch (parse_expr(dispP,&e)) {
case SEG_GOOF:
as_bad("expression syntax error");
break;
case SEG_TEXT:
case SEG_UNKNOWN:
if (var_frag) {
outP = frag_more(8); /* Allocate worst-case storage */
md_number_to_chars(outP, instr, 4);
frag_variant(rs_machine_dependent, 4, 4, 1,
adds(e), offs(e), outP, 0, 0);
} else {
/* Set up a new fix structure, so address can be updated
* when all symbol values are known.
*/
outP = emit(instr);
fixP = fix_new(frag_now,
outP - frag_now->fr_literal,
4,
adds(e),
0,
offs(e),
1,
0);
fixP->fx_callj = callj;
/* We want to modify a bit field when the address is
* known. But we don't need all the garbage in the
* bit_fix structure. So we're going to lie and store
* the number of bits affected instead of a pointer.
*/
fixP->fx_bit_fixP = (bit_fixS *) numbits;
}
break;
case SEG_DATA:
case SEG_BSS:
as_bad("attempt to branch into different segment");
break;
default:
as_bad("target of %s instruction must be a label", ifmtP);
break;
}
}
/*****************************************************************************
* get_ispec: parse a memory operand for an index specification
*
* Here, an "index specification" is taken to be anything surrounded
* by square brackets and NOT followed by anything else.
*
* If it's found, detach it from the input string, remove the surrounding
* square brackets, and return a pointer to it. Otherwise, return NULL.
*
**************************************************************************** */
static
char *
get_ispec(textP)
char *textP; /*->memory operand from source instruction, no white space */
{
char *start; /*->start of index specification */
char *end; /*->end of index specification */
/* Find opening square bracket, if any
*/
start = strchr(textP, '[');
if (start != NULL){
/* Eliminate '[', detach from rest of operand */
*start++ = '\0';
end = strchr(start, ']');
if (end == NULL){
as_bad("unmatched '['");
} else {
/* Eliminate ']' and make sure it was the last thing
* in the string.
*/
*end = '\0';
if (*(end+1) != '\0'){
as_bad("garbage after index spec ignored");
}
}
}
return start;
}
/*****************************************************************************
* get_regnum:
*
* Look up a (suspected) register name in the register table and return the
* associated register number (or -1 if not found).
*
**************************************************************************** */
static
int
get_regnum(regname)
char *regname; /* Suspected register name */
{
int *rP;
rP = (int *) hash_find(reg_hash, regname);
return (rP == NULL) ? -1 : *rP;
}
/*****************************************************************************
* i_scan: perform lexical scan of ascii assembler instruction.
*
* Input assumptions:
* - input string is an i80960 instruction (not a pseudo-op)
* - all comments and labels have been removed
* - all strings of whitespace have been collapsed to a single blank.
*
* Output:
* args[0] points to opcode, other entries point to operands. All strings:
* - are NULL-terminated
* - contain no whitespace
* - have character constants ('x') replaced with a decimal number
*
* Return value:
* Number of operands (0,1,2, or 3) or -1 on error.
*
**************************************************************************** */
static int i_scan(iP, args)
register char *iP; /* Pointer to ascii instruction; MUCKED BY US. */
char *args[]; /* Output arg: pointers to opcode and operands placed
* here. MUST ACCOMMODATE 4 ENTRIES.
*/
{
/* Isolate opcode */
if (*(iP) == ' ') {
iP++;
} /* Skip lead space, if any */
args[0] = iP;
for (; *iP != ' '; iP++) {
if (*iP == '\0') {
/* There are no operands */
if (args[0] == iP) {
/* We never moved: there was no opcode either! */
as_bad("missing opcode");
return -1;
}
return 0;
}
}
*iP++ = '\0'; /* Terminate opcode */
return(get_args(iP, args));
} /* i_scan() */
/*****************************************************************************
* mem_fmt: generate a MEMA- or MEMB-format instruction
*
**************************************************************************** */
static void mem_fmt(args, oP)
char *args[]; /* args[0]->opcode mnemonic, args[1-3]->operands */
struct i960_opcode *oP; /* Pointer to description of instruction */
{
int i; /* Loop counter */
struct regop regop; /* Description of register operand */
char opdesc; /* Operand descriptor byte */
memS instr; /* Description of binary to be output */
char *outP; /* Where the binary was output to */
expressionS expr; /* Parsed expression */
fixS *fixP; /*->description of deferred address fixup */
memset(&instr, '\0', sizeof(memS));
instr.opcode = oP->opcode;
/* Process operands. */
for (i = 1; i <= oP->num_ops; i++){
opdesc = oP->operand[i-1];
if (MEMOP(opdesc)){
parse_memop(&instr, args[i], oP->format);
} else {
parse_regop(&regop, args[i], opdesc);
instr.opcode |= regop.n << 19;
}
}
/* Output opcode */
outP = emit(instr.opcode);
if (instr.disp == 0){
return;
}
/* Parse and process the displacement */
switch (parse_expr(instr.e,&expr)){
case SEG_GOOF:
as_bad("expression syntax error");
break;
case SEG_ABSOLUTE:
if (instr.disp == 32){
(void) emit(offs(expr)); /* Output displacement */
} else {
/* 12-bit displacement */
if (offs(expr) & ~0xfff){
/* Won't fit in 12 bits: convert already-output
* instruction to MEMB format, output
* displacement.
*/
mema_to_memb(outP);
(void) emit(offs(expr));
} else {
/* WILL fit in 12 bits: OR into opcode and
* overwrite the binary we already put out
*/
instr.opcode |= offs(expr);
md_number_to_chars(outP, instr.opcode, 4);
}
}
break;
case SEG_DIFFERENCE:
case SEG_TEXT:
case SEG_DATA:
case SEG_BSS:
case SEG_UNKNOWN:
if (instr.disp == 12){
/* Displacement is dependent on a symbol, whose value
* may change at link time. We HAVE to reserve 32 bits.
* Convert already-output opcode to MEMB format.
*/
mema_to_memb(outP);
}
/* Output 0 displacement and set up address fixup for when
* this symbol's value becomes known.
*/
outP = emit((long) 0);
fixP = fix_new(frag_now,
outP - frag_now->fr_literal,
4,
adds(expr),
subs(expr),
offs(expr),
0,
0);
fixP->fx_im_disp = 2; /* 32-bit displacement fix */
break;
default:
BAD_CASE(segs(expr));
break;
}
} /* memfmt() */
/*****************************************************************************
* mema_to_memb: convert a MEMA-format opcode to a MEMB-format opcode.
*
* There are 2 possible MEMA formats:
* - displacement only
* - displacement + abase
*
* They are distinguished by the setting of the MEMA_ABASE bit.
*
**************************************************************************** */
static void mema_to_memb(opcodeP)
char *opcodeP; /* Where to find the opcode, in target byte order */
{
long opcode; /* Opcode in host byte order */
long mode; /* Mode bits for MEMB instruction */
opcode = md_chars_to_number(opcodeP, 4);
know(!(opcode & MEMB_BIT));
mode = MEMB_BIT | D_BIT;
if (opcode & MEMA_ABASE){
mode |= A_BIT;
}
opcode &= 0xffffc000; /* Clear MEMA offset and mode bits */
opcode |= mode; /* Set MEMB mode bits */
md_number_to_chars(opcodeP, opcode, 4);
} /* mema_to_memb() */
/*****************************************************************************
* parse_expr: parse an expression
*
* Use base assembler's expression parser to parse an expression.
* It, unfortunately, runs off a global which we have to save/restore
* in order to make it work for us.
*
* An empty expression string is treated as an absolute 0.
*
* Return "segment" to which the expression evaluates.
* Return SEG_GOOF regardless of expression evaluation if entire input
* string is not consumed in the evaluation -- tolerate no dangling junk!
*
**************************************************************************** */
static
segT
parse_expr(textP, expP)
char *textP; /* Text of expression to be parsed */
expressionS *expP; /* Where to put the results of parsing */
{
char *save_in; /* Save global here */
segT seg; /* Segment to which expression evaluates */
symbolS *symP;
know(textP);
if (*textP == '\0') {
/* Treat empty string as absolute 0 */
expP->X_add_symbol = expP->X_subtract_symbol = NULL;
expP->X_add_number = 0;
seg = expP->X_seg = SEG_ABSOLUTE;
} else {
save_in = input_line_pointer; /* Save global */
input_line_pointer = textP; /* Make parser work for us */
seg = expression(expP);
if (input_line_pointer - textP != strlen(textP)) {
/* Did not consume all of the input */
seg = SEG_GOOF;
}
symP = expP->X_add_symbol;
if (symP && (hash_find(reg_hash, S_GET_NAME(symP)))) {
/* Register name in an expression */
seg = SEG_GOOF;
}
input_line_pointer = save_in; /* Restore global */
}
return seg;
}
/*****************************************************************************
* parse_ldcont:
* Parse and replace a 'ldconst' pseudo-instruction with an appropriate
* i80960 instruction.
*
* Assumes the input consists of:
* arg[0] opcode mnemonic ('ldconst')
* arg[1] first operand (constant)
* arg[2] name of register to be loaded
*
* Replaces opcode and/or operands as appropriate.
*
* Returns the new number of arguments, or -1 on failure.
*
**************************************************************************** */
static
int
parse_ldconst(arg)
char *arg[]; /* See above */
{
int n; /* Constant to be loaded */
int shift; /* Shift count for "shlo" instruction */
static char buf[5]; /* Literal for first operand */
static char buf2[5]; /* Literal for second operand */
expressionS e; /* Parsed expression */
arg[3] = NULL; /* So we can tell at the end if it got used or not */
switch (parse_expr(arg[1],&e)){
case SEG_TEXT:
case SEG_DATA:
case SEG_BSS:
case SEG_UNKNOWN:
case SEG_DIFFERENCE:
/* We're dependent on one or more symbols -- use "lda" */
arg[0] = "lda";
break;
case SEG_ABSOLUTE:
/* Try the following mappings:
* ldconst 0,<reg> ->mov 0,<reg>
* ldconst 31,<reg> ->mov 31,<reg>
* ldconst 32,<reg> ->addo 1,31,<reg>
* ldconst 62,<reg> ->addo 31,31,<reg>
* ldconst 64,<reg> ->shlo 8,3,<reg>
* ldconst -1,<reg> ->subo 1,0,<reg>
* ldconst -31,<reg>->subo 31,0,<reg>
*
* anthing else becomes:
* lda xxx,<reg>
*/
n = offs(e);
if ((0 <= n) && (n <= 31)){
arg[0] = "mov";
} else if ((-31 <= n) && (n <= -1)){
arg[0] = "subo";
arg[3] = arg[2];
sprintf(buf, "%d", -n);
arg[1] = buf;
arg[2] = "0";
} else if ((32 <= n) && (n <= 62)){
arg[0] = "addo";
arg[3] = arg[2];
arg[1] = "31";
sprintf(buf, "%d", n-31);
arg[2] = buf;
} else if ((shift = shift_ok(n)) != 0){
arg[0] = "shlo";
arg[3] = arg[2];
sprintf(buf, "%d", shift);
arg[1] = buf;
sprintf(buf2, "%d", n >> shift);
arg[2] = buf2;
} else {
arg[0] = "lda";
}
break;
default:
as_bad("invalid constant");
return -1;
break;
}
return (arg[3] == 0) ? 2: 3;
}
/*****************************************************************************
* parse_memop: parse a memory operand
*
* This routine is based on the observation that the 4 mode bits of the
* MEMB format, taken individually, have fairly consistent meaning:
*
* M3 (bit 13): 1 if displacement is present (D_BIT)
* M2 (bit 12): 1 for MEMB instructions (MEMB_BIT)
* M1 (bit 11): 1 if index is present (I_BIT)
* M0 (bit 10): 1 if abase is present (A_BIT)
*
* So we parse the memory operand and set bits in the mode as we find
* things. Then at the end, if we go to MEMB format, we need only set
* the MEMB bit (M2) and our mode is built for us.
*
* Unfortunately, I said "fairly consistent". The exceptions:
*
* DBIA
* 0100 Would seem illegal, but means "abase-only".
*
* 0101 Would seem to mean "abase-only" -- it means IP-relative.
* Must be converted to 0100.
*
* 0110 Would seem to mean "index-only", but is reserved.
* We turn on the D bit and provide a 0 displacement.
*
* The other thing to observe is that we parse from the right, peeling
* things * off as we go: first any index spec, then any abase, then
* the displacement.
*
**************************************************************************** */
static
void
parse_memop(memP, argP, optype)
memS *memP; /* Where to put the results */
char *argP; /* Text of the operand to be parsed */
int optype; /* MEM1, MEM2, MEM4, MEM8, MEM12, or MEM16 */
{
char *indexP; /* Pointer to index specification with "[]" removed */
char *p; /* Temp char pointer */
char iprel_flag;/* True if this is an IP-relative operand */
int regnum; /* Register number */
int scale; /* Scale factor: 1,2,4,8, or 16. Later converted
* to internal format (0,1,2,3,4 respectively).
*/
int mode; /* MEMB mode bits */
int *intP; /* Pointer to register number */
/* The following table contains the default scale factors for each
* type of memory instruction. It is accessed using (optype-MEM1)
* as an index -- thus it assumes the 'optype' constants are assigned
* consecutive values, in the order they appear in this table
*/
static int def_scale[] = {
1, /* MEM1 */
2, /* MEM2 */
4, /* MEM4 */
8, /* MEM8 */
-1, /* MEM12 -- no valid default */
16 /* MEM16 */
};
iprel_flag = mode = 0;
/* Any index present? */
indexP = get_ispec(argP);
if (indexP) {
p = strchr(indexP, '*');
if (p == NULL) {
/* No explicit scale -- use default for this
*instruction type.
*/
scale = def_scale[ optype - MEM1 ];
} else {
*p++ = '\0'; /* Eliminate '*' */
/* Now indexP->a '\0'-terminated register name,
* and p->a scale factor.
*/
if (!strcmp(p,"16")){
scale = 16;
} else if (strchr("1248",*p) && (p[1] == '\0')){
scale = *p - '0';
} else {
scale = -1;
}
}
regnum = get_regnum(indexP); /* Get index reg. # */
if (!IS_RG_REG(regnum)){
as_bad("invalid index register");
return;
}
/* Convert scale to its binary encoding */
switch (scale){
case 1: scale = 0 << 7; break;
case 2: scale = 1 << 7; break;
case 4: scale = 2 << 7; break;
case 8: scale = 3 << 7; break;
case 16: scale = 4 << 7; break;
default: as_bad("invalid scale factor"); return;
};
memP->opcode |= scale | regnum; /* Set index bits in opcode */
mode |= I_BIT; /* Found a valid index spec */
}
/* Any abase (Register Indirect) specification present? */
if ((p = strrchr(argP,'(')) != NULL) {
/* "(" is there -- does it start a legal abase spec?
* (If not it could be part of a displacement expression.)
*/
intP = (int *) hash_find(areg_hash, p);
if (intP != NULL){
/* Got an abase here */
regnum = *intP;
*p = '\0'; /* discard register spec */
if (regnum == IPREL){
/* We have to specialcase ip-rel mode */
iprel_flag = 1;
} else {
memP->opcode |= regnum << 14;
mode |= A_BIT;
}
}
}
/* Any expression present? */
memP->e = argP;
if (*argP != '\0'){
mode |= D_BIT;
}
/* Special-case ip-relative addressing */
if (iprel_flag){
if (mode & I_BIT){
syntax();
} else {
memP->opcode |= 5 << 10; /* IP-relative mode */
memP->disp = 32;
}
return;
}
/* Handle all other modes */
switch (mode){
case D_BIT | A_BIT:
/* Go with MEMA instruction format for now (grow to MEMB later
* if 12 bits is not enough for the displacement).
* MEMA format has a single mode bit: set it to indicate
* that abase is present.
*/
memP->opcode |= MEMA_ABASE;
memP->disp = 12;
break;
case D_BIT:
/* Go with MEMA instruction format for now (grow to MEMB later
* if 12 bits is not enough for the displacement).
*/
memP->disp = 12;
break;
case A_BIT:
/* For some reason, the bit string for this mode is not
* consistent: it should be 0 (exclusive of the MEMB bit),
* so we set it "by hand" here.
*/
memP->opcode |= MEMB_BIT;
break;
case A_BIT | I_BIT:
/* set MEMB bit in mode, and OR in mode bits */
memP->opcode |= mode | MEMB_BIT;
break;
case I_BIT:
/* Treat missing displacement as displacement of 0 */
mode |= D_BIT;
/***********************
* Fall into next case *
********************** */
case D_BIT | A_BIT | I_BIT:
case D_BIT | I_BIT:
/* set MEMB bit in mode, and OR in mode bits */
memP->opcode |= mode | MEMB_BIT;
memP->disp = 32;
break;
default:
syntax();
break;
}
}
/*****************************************************************************
* parse_po: parse machine-dependent pseudo-op
*
* This is a top-level routine for machine-dependent pseudo-ops. It slurps
* up the rest of the input line, breaks out the individual arguments,
* and dispatches them to the correct handler.
**************************************************************************** */
static
void
parse_po(po_num)
int po_num; /* Pseudo-op number: currently S_LEAFPROC or S_SYSPROC */
{
char *args[4]; /* Pointers operands, with no embedded whitespace.
* arg[0] unused.
* arg[1-3]->operands
*/
int n_ops; /* Number of operands */
char *p; /* Pointer to beginning of unparsed argument string */
char eol; /* Character that indicated end of line */
extern char is_end_of_line[];
/* Advance input pointer to end of line. */
p = input_line_pointer;
while (!is_end_of_line[ *input_line_pointer ]){
input_line_pointer++;
}
eol = *input_line_pointer; /* Save end-of-line char */
*input_line_pointer = '\0'; /* Terminate argument list */
/* Parse out operands */
n_ops = get_args(p, args);
if (n_ops == -1){
return;
}
/* Dispatch to correct handler */
switch (po_num){
case S_SYSPROC: s_sysproc(n_ops, args); break;
case S_LEAFPROC: s_leafproc(n_ops, args); break;
default: BAD_CASE(po_num); break;
}
/* Restore eol, so line numbers get updated correctly. Base assembler
* assumes we leave input pointer pointing at char following the eol.
*/
*input_line_pointer++ = eol;
}
/*****************************************************************************
* parse_regop: parse a register operand.
*
* In case of illegal operand, issue a message and return some valid
* information so instruction processing can continue.
**************************************************************************** */
static
void
parse_regop(regopP, optext, opdesc)
struct regop *regopP; /* Where to put description of register operand */
char *optext; /* Text of operand */
char opdesc; /* Descriptor byte: what's legal for this operand */
{
int n; /* Register number */
expressionS e; /* Parsed expression */
/* See if operand is a register */
n = get_regnum(optext);
if (n >= 0){
if (IS_RG_REG(n)){
/* global or local register */
if (!REG_ALIGN(opdesc,n)){
as_bad("unaligned register");
}
regopP->n = n;
regopP->mode = 0;
regopP->special = 0;
return;
} else if (IS_FP_REG(n) && FP_OK(opdesc)){
/* Floating point register, and it's allowed */
regopP->n = n - FP0;
regopP->mode = 1;
regopP->special = 0;
return;
} else if (IS_SF_REG(n) && SFR_OK(opdesc)){
/* Special-function register, and it's allowed */
regopP->n = n - SF0;
regopP->mode = 0;
regopP->special = 1;
if (!targ_has_sfr(regopP->n)){
as_bad("no such sfr in this architecture");
}
return;
}
} else if (LIT_OK(opdesc)){
/*
* How about a literal?
*/
regopP->mode = 1;
regopP->special = 0;
if (FP_OK(opdesc)){ /* floating point literal acceptable */
/* Skip over 0f, 0d, or 0e prefix */
if ( (optext[0] == '0')
&& (optext[1] >= 'd')
&& (optext[1] <= 'f') ){
optext += 2;
}
if (!strcmp(optext,"0.0") || !strcmp(optext,"0") ){
regopP->n = 0x10;
return;
}
if (!strcmp(optext,"1.0") || !strcmp(optext,"1") ){
regopP->n = 0x16;
return;
}
} else { /* fixed point literal acceptable */
if ((parse_expr(optext,&e) != SEG_ABSOLUTE)
|| (offs(e) < 0) || (offs(e) > 31)){
as_bad("illegal literal");
offs(e) = 0;
}
regopP->n = offs(e);
return;
}
}
/* Nothing worked */
syntax();
regopP->mode = 0; /* Register r0 is always a good one */
regopP->n = 0;
regopP->special = 0;
} /* parse_regop() */
/*****************************************************************************
* reg_fmt: generate a REG-format instruction
*
**************************************************************************** */
static void reg_fmt(args, oP)
char *args[]; /* args[0]->opcode mnemonic, args[1-3]->operands */
struct i960_opcode *oP; /* Pointer to description of instruction */
{
long instr; /* Binary to be output */
struct regop regop; /* Description of register operand */
int n_ops; /* Number of operands */
instr = oP->opcode;
n_ops = oP->num_ops;
if (n_ops >= 1){
parse_regop(&regop, args[1], oP->operand[0]);
if ((n_ops == 1) && !(instr & M3)){
/* 1-operand instruction in which the dst field should
* be used (instead of src1).
*/
regop.n <<= 19;
if (regop.special){
regop.mode = regop.special;
}
regop.mode <<= 13;
regop.special = 0;
} else {
/* regop.n goes in bit 0, needs no shifting */
regop.mode <<= 11;
regop.special <<= 5;
}
instr |= regop.n | regop.mode | regop.special;
}
if (n_ops >= 2) {
parse_regop(&regop, args[2], oP->operand[1]);
if ((n_ops == 2) && !(instr & M3)){
/* 2-operand instruction in which the dst field should
* be used instead of src2).
*/
regop.n <<= 19;
if (regop.special){
regop.mode = regop.special;
}
regop.mode <<= 13;
regop.special = 0;
} else {
regop.n <<= 14;
regop.mode <<= 12;
regop.special <<= 6;
}
instr |= regop.n | regop.mode | regop.special;
}
if (n_ops == 3){
parse_regop(&regop, args[3], oP->operand[2]);
if (regop.special){
regop.mode = regop.special;
}
instr |= (regop.n <<= 19) | (regop.mode <<= 13);
}
emit(instr);
}
/*****************************************************************************
* relax_cobr:
* Replace cobr instruction in a code fragment with equivalent branch and
* compare instructions, so it can reach beyond a 13-bit displacement.
* Set up an address fix/relocation for the new branch instruction.
*
**************************************************************************** */
/* This "conditional jump" table maps cobr instructions into equivalent
* compare and branch opcodes.
*/
static
struct {
long compare;
long branch;
} coj[] = { /* COBR OPCODE: */
CHKBIT, BNO, /* 0x30 - bbc */
CMPO, BG, /* 0x31 - cmpobg */
CMPO, BE, /* 0x32 - cmpobe */
CMPO, BGE, /* 0x33 - cmpobge */
CMPO, BL, /* 0x34 - cmpobl */
CMPO, BNE, /* 0x35 - cmpobne */
CMPO, BLE, /* 0x36 - cmpoble */
CHKBIT, BO, /* 0x37 - bbs */
CMPI, BNO, /* 0x38 - cmpibno */
CMPI, BG, /* 0x39 - cmpibg */
CMPI, BE, /* 0x3a - cmpibe */
CMPI, BGE, /* 0x3b - cmpibge */
CMPI, BL, /* 0x3c - cmpibl */
CMPI, BNE, /* 0x3d - cmpibne */
CMPI, BLE, /* 0x3e - cmpible */
CMPI, BO, /* 0x3f - cmpibo */
};
static
void
relax_cobr(fragP)
register fragS *fragP; /* fragP->fr_opcode is assumed to point to
* the cobr instruction, which comes at the
* end of the code fragment.
*/
{
int opcode, src1, src2, m1, s2;
/* Bit fields from cobr instruction */
long bp_bits; /* Branch prediction bits from cobr instruction */
long instr; /* A single i960 instruction */
char *iP; /*->instruction to be replaced */
fixS *fixP; /* Relocation that can be done at assembly time */
/* PICK UP & PARSE COBR INSTRUCTION */
iP = fragP->fr_opcode;
instr = md_chars_to_number(iP, 4);
opcode = ((instr >> 24) & 0xff) - 0x30; /* "-0x30" for table index */
src1 = (instr >> 19) & 0x1f;
m1 = (instr >> 13) & 1;
s2 = instr & 1;
src2 = (instr >> 14) & 0x1f;
bp_bits= instr & BP_MASK;
/* GENERATE AND OUTPUT COMPARE INSTRUCTION */
instr = coj[opcode].compare
| src1 | (m1 << 11) | (s2 << 6) | (src2 << 14);
md_number_to_chars(iP, instr, 4);
/* OUTPUT BRANCH INSTRUCTION */
md_number_to_chars(iP+4, coj[opcode].branch | bp_bits, 4);
/* SET UP ADDRESS FIXUP/RELOCATION */
fixP = fix_new(fragP,
iP+4 - fragP->fr_literal,
4,
fragP->fr_symbol,
0,
fragP->fr_offset,
1,
0);
fixP->fx_bit_fixP = (bit_fixS *) 24; /* Store size of bit field */
fragP->fr_fix += 4;
frag_wane(fragP);
}
/*****************************************************************************
* reloc_callj: Relocate a 'callj' instruction
*
* This is a "non-(GNU)-standard" machine-dependent hook. The base
* assembler calls it when it decides it can relocate an address at
* assembly time instead of emitting a relocation directive.
*
* Check to see if the relocation involves a 'callj' instruction to a:
* sysproc: Replace the default 'call' instruction with a 'calls'
* leafproc: Replace the default 'call' instruction with a 'bal'.
* other proc: Do nothing.
*
* See b.out.h for details on the 'n_other' field in a symbol structure.
*
* IMPORTANT!:
* Assumes the caller has already figured out, in the case of a leafproc,
* to use the 'bal' entry point, and has substituted that symbol into the
* passed fixup structure.
*
**************************************************************************** */
void reloc_callj(fixP)
fixS *fixP; /* Relocation that can be done at assembly time */
{
char *where; /*->the binary for the instruction being relocated */
if (!fixP->fx_callj) {
return;
} /* This wasn't a callj instruction in the first place */
where = fixP->fx_frag->fr_literal + fixP->fx_where;
if (TC_S_IS_SYSPROC(fixP->fx_addsy)) {
/* Symbol is a .sysproc: replace 'call' with 'calls'.
* System procedure number is (other-1).
*/
md_number_to_chars(where, CALLS|TC_S_GET_SYSPROC(fixP->fx_addsy), 4);
/* Nothing else needs to be done for this instruction.
* Make sure 'md_number_to_field()' will perform a no-op.
*/
fixP->fx_bit_fixP = (bit_fixS *) 1;
} else if (TC_S_IS_CALLNAME(fixP->fx_addsy)) {
/* Should not happen: see block comment above */
as_fatal("Trying to 'bal' to %s", S_GET_NAME(fixP->fx_addsy));
} else if (TC_S_IS_BALNAME(fixP->fx_addsy)) {
/* Replace 'call' with 'bal'; both instructions have
* the same format, so calling code should complete
* relocation as if nothing happened here.
*/
md_number_to_chars(where, BAL, 4);
} else if (TC_S_IS_BADPROC(fixP->fx_addsy)) {
as_bad("Looks like a proc, but can't tell what kind.\n");
} /* switch on proc type */
/* else Symbol is neither a sysproc nor a leafproc */
return;
} /* reloc_callj() */
/*****************************************************************************
* s_leafproc: process .leafproc pseudo-op
*
* .leafproc takes two arguments, the second one is optional:
* arg[1]: name of 'call' entry point to leaf procedure
* arg[2]: name of 'bal' entry point to leaf procedure
*
* If the two arguments are identical, or if the second one is missing,
* the first argument is taken to be the 'bal' entry point.
*
* If there are 2 distinct arguments, we must make sure that the 'bal'
* entry point immediately follows the 'call' entry point in the linked
* list of symbols.
*
**************************************************************************** */
static void s_leafproc(n_ops, args)
int n_ops; /* Number of operands */
char *args[]; /* args[1]->1st operand, args[2]->2nd operand */
{
symbolS *callP; /* Pointer to leafproc 'call' entry point symbol */
symbolS *balP; /* Pointer to leafproc 'bal' entry point symbol */
if ((n_ops != 1) && (n_ops != 2)) {
as_bad("should have 1 or 2 operands");
return;
} /* Check number of arguments */
/* Find or create symbol for 'call' entry point. */
callP = symbol_find_or_make(args[1]);
if (TC_S_IS_CALLNAME(callP)) {
as_warn("Redefining leafproc %s", S_GET_NAME(callP));
} /* is leafproc */
/* If that was the only argument, use it as the 'bal' entry point.
* Otherwise, mark it as the 'call' entry point and find or create
* another symbol for the 'bal' entry point.
*/
if ((n_ops == 1) || !strcmp(args[1],args[2])) {
TC_S_FORCE_TO_BALNAME(callP);
} else {
TC_S_FORCE_TO_CALLNAME(callP);
balP = symbol_find_or_make(args[2]);
if (TC_S_IS_CALLNAME(balP)) {
as_warn("Redefining leafproc %s", S_GET_NAME(balP));
}
TC_S_FORCE_TO_BALNAME(balP);
tc_set_bal_of_call(callP, balP);
} /* if only one arg, or the args are the same */
return;
} /* s_leafproc() */
/*
* s_sysproc: process .sysproc pseudo-op
*
* .sysproc takes two arguments:
* arg[1]: name of entry point to system procedure
* arg[2]: 'entry_num' (index) of system procedure in the range
* [0,31] inclusive.
*
* For [ab].out, we store the 'entrynum' in the 'n_other' field of
* the symbol. Since that entry is normally 0, we bias 'entrynum'
* by adding 1 to it. It must be unbiased before it is used.
*/
static void s_sysproc(n_ops, args)
int n_ops; /* Number of operands */
char *args[]; /* args[1]->1st operand, args[2]->2nd operand */
{
expressionS exp;
symbolS *symP;
if (n_ops != 2) {
as_bad("should have two operands");
return;
} /* bad arg count */
/* Parse "entry_num" argument and check it for validity. */
if ((parse_expr(args[2],&exp) != SEG_ABSOLUTE)
|| (offs(exp) < 0)
|| (offs(exp) > 31)) {
as_bad("'entry_num' must be absolute number in [0,31]");
return;
}
/* Find/make symbol and stick entry number (biased by +1) into it */
symP = symbol_find_or_make(args[1]);
if (TC_S_IS_SYSPROC(symP)) {
as_warn("Redefining entrynum for sysproc %s", S_GET_NAME(symP));
} /* redefining */
TC_S_SET_SYSPROC(symP, offs(exp)); /* encode entry number */
TC_S_FORCE_TO_SYSPROC(symP);
return;
} /* s_sysproc() */
/*****************************************************************************
* shift_ok:
* Determine if a "shlo" instruction can be used to implement a "ldconst".
* This means that some number X < 32 can be shifted left to produce the
* constant of interest.
*
* Return the shift count, or 0 if we can't do it.
* Caller calculates X by shifting original constant right 'shift' places.
*
**************************************************************************** */
static
int
shift_ok(n)
int n; /* The constant of interest */
{
int shift; /* The shift count */
if (n <= 0){
/* Can't do it for negative numbers */
return 0;
}
/* Shift 'n' right until a 1 is about to be lost */
for (shift = 0; (n & 1) == 0; shift++){
n >>= 1;
}
if (n >= 32){
return 0;
}
return shift;
}
/*****************************************************************************
* syntax: issue syntax error
*
**************************************************************************** */
static void syntax() {
as_bad("syntax error");
} /* syntax() */
/*****************************************************************************
* targ_has_sfr:
* Return TRUE iff the target architecture supports the specified
* special-function register (sfr).
*
**************************************************************************** */
static
int
targ_has_sfr(n)
int n; /* Number (0-31) of sfr */
{
switch (architecture){
case ARCH_KA:
case ARCH_KB:
case ARCH_MC:
return 0;
case ARCH_CA:
default:
return ((0 <= n) && (n <= 2));
}
}
/*****************************************************************************
* targ_has_iclass:
* Return TRUE iff the target architecture supports the indicated
* class of instructions.
*
**************************************************************************** */
static
int
targ_has_iclass(ic)
int ic; /* Instruction class; one of:
* I_BASE, I_CX, I_DEC, I_KX, I_FP, I_MIL, I_CASIM
*/
{
iclasses_seen |= ic;
switch (architecture){
case ARCH_KA: return ic & (I_BASE | I_KX);
case ARCH_KB: return ic & (I_BASE | I_KX | I_FP | I_DEC);
case ARCH_MC: return ic & (I_BASE | I_KX | I_FP | I_DEC | I_MIL);
case ARCH_CA: return ic & (I_BASE | I_CX | I_CASIM);
default:
if ((iclasses_seen & (I_KX|I_FP|I_DEC|I_MIL))
&& (iclasses_seen & I_CX)){
as_warn("architecture of opcode conflicts with that of earlier instruction(s)");
iclasses_seen &= ~ic;
}
return 1;
}
}
/* Parse an operand that is machine-specific.
We just return without modifying the expression if we have nothing
to do. */
/* ARGSUSED */
void
md_operand (expressionP)
expressionS *expressionP;
{
}
/* We have no need to default values of symbols. */
/* ARGSUSED */
symbolS *md_undefined_symbol(name)
char *name;
{
return 0;
} /* md_undefined_symbol() */
/* Exactly what point is a PC-relative offset relative TO?
On the i960, they're relative to the address of the instruction,
which we have set up as the address of the fixup too. */
long
md_pcrel_from (fixP)
fixS *fixP;
{
return fixP->fx_where + fixP->fx_frag->fr_address;
}
void
md_apply_fix(fixP, val)
fixS *fixP;
long val;
{
char *place = fixP->fx_where + fixP->fx_frag->fr_literal;
if (!fixP->fx_bit_fixP) {
switch (fixP->fx_im_disp) {
case 0:
fixP->fx_addnumber = val;
md_number_to_imm(place, val, fixP->fx_size, fixP);
break;
case 1:
md_number_to_disp(place,
fixP->fx_pcrel ? val + fixP->fx_pcrel_adjust : val,
fixP->fx_size);
break;
case 2: /* fix requested for .long .word etc */
md_number_to_chars(place, val, fixP->fx_size);
break;
default:
as_fatal("Internal error in md_apply_fix() in file \"%s\"", __FILE__);
} /* OVE: maybe one ought to put _imm _disp _chars in one md-func */
} else {
md_number_to_field(place, val, fixP->fx_bit_fixP);
}
return;
} /* md_apply_fix() */
#if defined(OBJ_AOUT) | defined(OBJ_BOUT)
void tc_bout_fix_to_chars(where, fixP, segment_address_in_file)
char *where;
fixS *fixP;
relax_addressT segment_address_in_file;
{
static unsigned char nbytes_r_length[] = { 42, 0, 1, 42, 2 };
struct relocation_info ri;
symbolS *symbolP;
/* JF this is for paranoia */
memset((char *)&ri, '\0', sizeof(ri));
know((symbolP = fixP->fx_addsy) != 0);
/* These two 'cuz of NS32K */
ri.r_callj = fixP->fx_callj;
ri.r_length = nbytes_r_length[fixP->fx_size];
ri.r_pcrel = fixP->fx_pcrel;
ri.r_address = fixP->fx_frag->fr_address + fixP->fx_where - segment_address_in_file;
if (!S_IS_DEFINED(symbolP)) {
ri.r_extern = 1;
ri.r_index = symbolP->sy_number;
} else {
ri.r_extern = 0;
ri.r_index = S_GET_TYPE(symbolP);
}
/* Output the relocation information in machine-dependent form. */
md_ri_to_chars(where, &ri);
return;
} /* tc_bout_fix_to_chars() */
#endif /* OBJ_AOUT or OBJ_BOUT */
/* Align an address by rounding it up to the specified boundary.
*/
long md_section_align(seg, addr)
segT seg;
long addr; /* Address to be rounded up */
{
return((addr + (1 << section_alignment[(int) seg]) - 1) & (-1 << section_alignment[(int) seg]));
} /* md_section_align() */
#ifdef OBJ_COFF
void tc_headers_hook(headers)
object_headers *headers;
{
/* FIXME: remove this line */ /* unsigned short arch_flag = 0; */
if ((iclasses_seen == I_BASE) || (iclasses_seen == 0)) {
headers->filehdr.f_flags |= F_I960CORE;
} else if (iclasses_seen & I_CX){
headers->filehdr.f_flags |= F_I960CA;
} else if (iclasses_seen & I_MIL){
headers->filehdr.f_flags |= F_I960MC;
} else if (iclasses_seen & (I_DEC|I_FP)){
headers->filehdr.f_flags |= F_I960KB;
} else {
headers->filehdr.f_flags |= F_I960KA;
} /* set arch flag */
if (flagseen['R']) {
headers->filehdr.f_magic = I960RWMAGIC;
headers->aouthdr.magic = OMAGIC;
} else {
headers->filehdr.f_magic = I960ROMAGIC;
headers->aouthdr.magic = NMAGIC;
} /* set magic numbers */
return;
} /* tc_headers_hook() */
#endif /* OBJ_COFF */
/*
* Things going on here:
*
* For bout, We need to assure a couple of simplifying
* assumptions about leafprocs for the linker: the leafproc
* entry symbols will be defined in the same assembly in
* which they're declared with the '.leafproc' directive;
* and if a leafproc has both 'call' and 'bal' entry points
* they are both global or both local.
*
* For coff, the call symbol has a second aux entry that
* contains the bal entry point. The bal symbol becomes a
* label.
*
* For coff representation, the call symbol has a second aux entry that
* contains the bal entry point. The bal symbol becomes a label.
*
*/
void tc_crawl_symbol_chain(headers)
object_headers *headers;
{
symbolS *symbolP;
for (symbolP = symbol_rootP; symbolP; symbolP = symbol_next(symbolP)) {
#ifdef OBJ_COFF
if (TC_S_IS_SYSPROC(symbolP)) {
/* second aux entry already contains the sysproc number */
S_SET_NUMBER_AUXILIARY(symbolP, 2);
S_SET_STORAGE_CLASS(symbolP, C_SCALL);
S_SET_DATA_TYPE(symbolP, S_GET_DATA_TYPE(symbolP) | (DT_FCN << N_BTSHFT));
continue;
} /* rewrite sysproc */
#endif /* OBJ_COFF */
if (!TC_S_IS_BALNAME(symbolP) && !TC_S_IS_CALLNAME(symbolP)) {
continue;
} /* Not a leafproc symbol */
if (!S_IS_DEFINED(symbolP)) {
as_bad("leafproc symbol '%s' undefined", S_GET_NAME(symbolP));
} /* undefined leaf */
if (TC_S_IS_CALLNAME(symbolP)) {
symbolS *balP = tc_get_bal_of_call(symbolP);
if (S_IS_EXTERNAL(symbolP) != S_IS_EXTERNAL(balP)) {
S_SET_EXTERNAL(symbolP);
S_SET_EXTERNAL(balP);
as_warn("Warning: making leafproc entries %s and %s both global\n",
S_GET_NAME(symbolP), S_GET_NAME(balP));
} /* externality mismatch */
} /* if callname */
} /* walk the symbol chain */
return;
} /* tc_crawl_symbol_chain() */
/*
* For aout or bout, the bal immediately follows the call.
*
* For coff, we cheat and store a pointer to the bal symbol
* in the second aux entry of the call.
*/
void tc_set_bal_of_call(callP, balP)
symbolS *callP;
symbolS *balP;
{
know(TC_S_IS_CALLNAME(callP));
know(TC_S_IS_BALNAME(balP));
#ifdef OBJ_COFF
callP->sy_symbol.ost_auxent[1].x_bal.x_balntry = (int) balP;
S_SET_NUMBER_AUXILIARY(callP,2);
#elif defined(OBJ_AOUT) || defined(OBJ_BOUT)
/* If the 'bal' entry doesn't immediately follow the 'call'
* symbol, unlink it from the symbol list and re-insert it.
*/
if (symbol_next(callP) != balP) {
symbol_remove(balP, &symbol_rootP, &symbol_lastP);
symbol_append(balP, callP, &symbol_rootP, &symbol_lastP);
} /* if not in order */
#else
(as yet unwritten.);
#endif /* switch on OBJ_FORMAT */
return;
} /* tc_set_bal_of_call() */
char *_tc_get_bal_of_call(callP)
symbolS *callP;
{
symbolS *retval;
know(TC_S_IS_CALLNAME(callP));
#ifdef OBJ_COFF
retval = (symbolS *) (callP->sy_symbol.ost_auxent[1].x_bal.x_balntry);
#elif defined(OBJ_AOUT) || defined(OBJ_BOUT)
retval = symbol_next(callP);
#else
(as yet unwritten.);
#endif /* switch on OBJ_FORMAT */
know(TC_S_IS_BALNAME(retval));
return((char *) retval);
} /* _tc_get_bal_of_call() */
void tc_coff_symbol_emit_hook(symbolP)
symbolS *symbolP;
{
if (TC_S_IS_CALLNAME(symbolP)) {
#ifdef OBJ_COFF
symbolS *balP = tc_get_bal_of_call(symbolP);
/* second aux entry contains the bal entry point */
/* S_SET_NUMBER_AUXILIARY(symbolP, 2); */
symbolP->sy_symbol.ost_auxent[1].x_bal.x_balntry = S_GET_VALUE(balP);
S_SET_STORAGE_CLASS(symbolP, (!SF_GET_LOCAL(symbolP) ? C_LEAFEXT : C_LEAFSTAT));
S_SET_DATA_TYPE(symbolP, S_GET_DATA_TYPE(symbolP) | (DT_FCN << N_BTSHFT));
/* fix up the bal symbol */
S_SET_STORAGE_CLASS(balP, C_LABEL);
#endif /* OBJ_COFF */
} /* only on calls */
return;
} /* tc_coff_symbol_emit_hook() */
/*
* Local Variables:
* comment-column: 0
* fill-column: 131
* End:
*/
/* end of tc-i960.c */
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