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nasm/assemble.c
H. Peter Anvin 09f6acbb75 NASM 0.98.21
2002-04-30 21:05:55 +00:00

1461 lines
42 KiB
C
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/* assemble.c code generation for the Netwide Assembler
*
* The Netwide Assembler is copyright (C) 1996 Simon Tatham and
* Julian Hall. All rights reserved. The software is
* redistributable under the licence given in the file "Licence"
* distributed in the NASM archive.
*
* the actual codes (C syntax, i.e. octal):
* \0 - terminates the code. (Unless it's a literal of course.)
* \1, \2, \3 - that many literal bytes follow in the code stream
* \4, \6 - the POP/PUSH (respectively) codes for CS, DS, ES, SS
* (POP is never used for CS) depending on operand 0
* \5, \7 - the second byte of POP/PUSH codes for FS, GS, depending
* on operand 0
* \10, \11, \12 - a literal byte follows in the code stream, to be added
* to the register value of operand 0, 1 or 2
* \17 - encodes the literal byte 0. (Some compilers don't take
* kindly to a zero byte in the _middle_ of a compile time
* string constant, so I had to put this hack in.)
* \14, \15, \16 - a signed byte immediate operand, from operand 0, 1 or 2
* \20, \21, \22 - a byte immediate operand, from operand 0, 1 or 2
* \24, \25, \26 - an unsigned byte immediate operand, from operand 0, 1 or 2
* \30, \31, \32 - a word immediate operand, from operand 0, 1 or 2
* \34, \35, \36 - select between \3[012] and \4[012] depending on 16/32 bit
* assembly mode or the address-size override on the operand
* \37 - a word constant, from the _segment_ part of operand 0
* \40, \41, \42 - a long immediate operand, from operand 0, 1 or 2
* \50, \51, \52 - a byte relative operand, from operand 0, 1 or 2
* \60, \61, \62 - a word relative operand, from operand 0, 1 or 2
* \64, \65, \66 - select between \6[012] and \7[012] depending on 16/32 bit
* assembly mode or the address-size override on the operand
* \70, \71, \72 - a long relative operand, from operand 0, 1 or 2
* \1ab - a ModRM, calculated on EA in operand a, with the spare
* field the register value of operand b.
* \130,\131,\132 - an immediate word or signed byte for operand 0, 1, or 2
* \133,\134,\135 - or 2 (s-field) into next opcode byte if operand 0, 1, or 2
* is a signed byte rather than a word.
* \140,\141,\142 - an immediate dword or signed byte for operand 0, 1, or 2
* \143,\144,\145 - or 2 (s-field) into next opcode byte if operand 0, 1, or 2
* is a signed byte rather than a dword.
* \2ab - a ModRM, calculated on EA in operand a, with the spare
* field equal to digit b.
* \30x - might be an 0x67 byte, depending on the address size of
* the memory reference in operand x.
* \310 - indicates fixed 16-bit address size, i.e. optional 0x67.
* \311 - indicates fixed 32-bit address size, i.e. optional 0x67.
* \312 - (disassembler only) marker on LOOP, LOOPxx instructions.
* \320 - indicates fixed 16-bit operand size, i.e. optional 0x66.
* \321 - indicates fixed 32-bit operand size, i.e. optional 0x66.
* \322 - indicates that this instruction is only valid when the
* operand size is the default (instruction to disassembler,
* generates no code in the assembler)
* \330 - a literal byte follows in the code stream, to be added
* to the condition code value of the instruction.
* \331 - instruction not valid with REP prefix. Hint for
* disassembler only; for SSE instructions.
* \332 - disassemble a rep (0xF3 byte) prefix as repe not rep.
* \333 - REP prefix (0xF3 byte); for SSE instructions. Not encoded
* as a literal byte in order to aid the disassembler.
* \340 - reserve <operand 0> bytes of uninitialised storage.
* Operand 0 had better be a segmentless constant.
* \370,\371,\372 - match only if operand 0 meets byte jump criteria.
* 370 is used for Jcc, 371 is used for JMP.
* \373 - assemble 0x03 if bits==16, 0x05 if bits==32;
* used for conditional jump over longer jump
*/
#include <stdio.h>
#include <string.h>
#include "nasm.h"
#include "nasmlib.h"
#include "assemble.h"
#include "insns.h"
extern struct itemplate *nasm_instructions[];
typedef struct {
int sib_present; /* is a SIB byte necessary? */
int bytes; /* # of bytes of offset needed */
int size; /* lazy - this is sib+bytes+1 */
unsigned char modrm, sib; /* the bytes themselves */
} ea;
static unsigned long cpu; /* cpu level received from nasm.c */
static efunc errfunc;
static struct ofmt *outfmt;
static ListGen *list;
static long calcsize (long, long, int, insn *, char *);
static void gencode (long, long, int, insn *, char *, long);
static int regval (operand *o);
static int matches (struct itemplate *, insn *);
static ea * process_ea (operand *, ea *, int, int, int);
static int chsize (operand *, int);
/*
* This routine wrappers the real output format's output routine,
* in order to pass a copy of the data off to the listing file
* generator at the same time.
*/
static void out (long offset, long segto, void *data, unsigned long type,
long segment, long wrt)
{
long lineno;
char *lnfname = NULL;
if ((type & OUT_TYPMASK) == OUT_ADDRESS) {
if (segment != NO_SEG || wrt != NO_SEG) {
/*
* This address is relocated. We must write it as
* OUT_ADDRESS, so there's no work to be done here.
*/
list->output (offset, data, type);
}
else {
unsigned char p[4], *q = p;
/*
* This is a non-relocated address, and we're going to
* convert it into RAWDATA format.
*/
if ((type & OUT_SIZMASK) == 4) {
WRITELONG (q, * (long *) data);
list->output (offset, p, OUT_RAWDATA+4);
}
else {
WRITESHORT (q, * (long *) data);
list->output (offset, p, OUT_RAWDATA+2);
}
}
}
else if ((type & OUT_TYPMASK) == OUT_RAWDATA) {
list->output (offset, data, type);
}
else if ((type & OUT_TYPMASK) == OUT_RESERVE) {
list->output (offset, NULL, type);
}
else if ((type & OUT_TYPMASK) == OUT_REL2ADR ||
(type & OUT_TYPMASK) == OUT_REL4ADR) {
list->output (offset, data, type);
}
if (src_get(&lineno,&lnfname))
{
outfmt->current_dfmt->linenum(lnfname,lineno,segto);
if (lnfname) nasm_free(lnfname);
}
outfmt->output (segto, data, type, segment, wrt);
}
static int jmp_match (long segment, long offset, int bits,
insn *ins, char *code)
{ long isize;
unsigned char c = code[0];
if (c != 0370 && c != 0371) return 0;
if (ins->oprs[0].opflags & OPFLAG_FORWARD) {
if (optimizing<0 && c==0370) return 1;
else return (pass0==0); /* match a forward reference */
}
isize = calcsize (segment, offset, bits, ins, code);
if (ins->oprs[0].segment != segment) return 0;
isize = ins->oprs[0].offset - offset - isize; /* isize is now the delta */
if (isize >= -128L && isize <= 127L) return 1; /* it is byte size */
return 0;
}
long assemble (long segment, long offset, int bits, unsigned long cp,
insn *instruction, struct ofmt *output, efunc error,
ListGen *listgen)
{
struct itemplate *temp;
int j;
int size_prob;
long insn_end;
long itimes;
long start = offset;
long wsize = 0; /* size for DB etc. */
errfunc = error; /* to pass to other functions */
cpu = cp;
outfmt = output; /* likewise */
list = listgen; /* and again */
switch (instruction->opcode)
{
case -1: return 0;
case I_DB: wsize = 1; break;
case I_DW: wsize = 2; break;
case I_DD: wsize = 4; break;
case I_DQ: wsize = 8; break;
case I_DT: wsize = 10; break;
}
if (wsize) {
extop * e;
long t = instruction->times;
if (t < 0)
errfunc(ERR_PANIC, "instruction->times < 0 (%ld) in assemble()",t);
while (t--) /* repeat TIMES times */
{
for (e = instruction->eops; e; e = e->next)
{
if (e->type == EOT_DB_NUMBER)
{
if (wsize == 1) {
if (e->segment != NO_SEG)
errfunc (ERR_NONFATAL,
"one-byte relocation attempted");
else {
unsigned char out_byte = e->offset;
out (offset, segment, &out_byte, OUT_RAWDATA+1,
NO_SEG, NO_SEG);
}
}
else if (wsize > 5) {
errfunc (ERR_NONFATAL, "integer supplied to a D%c"
" instruction", wsize==8 ? 'Q' : 'T');
}
else
out (offset, segment, &e->offset,
OUT_ADDRESS+wsize, e->segment,
e->wrt);
offset += wsize;
}
else if (e->type == EOT_DB_STRING)
{
int align;
out (offset, segment, e->stringval,
OUT_RAWDATA+e->stringlen, NO_SEG, NO_SEG);
align = e->stringlen % wsize;
if (align) {
align = wsize - align;
out (offset, segment, "\0\0\0\0\0\0\0\0",
OUT_RAWDATA+align, NO_SEG, NO_SEG);
}
offset += e->stringlen + align;
}
}
if (t > 0 && t == instruction->times-1)
{
/*
* Dummy call to list->output to give the offset to the
* listing module.
*/
list->output (offset, NULL, OUT_RAWDATA);
list->uplevel (LIST_TIMES);
}
}
if (instruction->times > 1)
list->downlevel (LIST_TIMES);
return offset - start;
}
if (instruction->opcode == I_INCBIN)
{
static char fname[FILENAME_MAX];
FILE * fp;
long len;
len = FILENAME_MAX-1;
if (len > instruction->eops->stringlen)
len = instruction->eops->stringlen;
strncpy (fname, instruction->eops->stringval, len);
fname[len] = '\0';
if ( (fp = fopen(fname, "rb")) == NULL)
error (ERR_NONFATAL, "`incbin': unable to open file `%s'", fname);
else if (fseek(fp, 0L, SEEK_END) < 0)
error (ERR_NONFATAL, "`incbin': unable to seek on file `%s'",
fname);
else
{
static char buf[2048];
long t = instruction->times;
long base = 0;
len = ftell (fp);
if (instruction->eops->next) {
base = instruction->eops->next->offset;
len -= base;
if (instruction->eops->next->next &&
len > instruction->eops->next->next->offset)
len = instruction->eops->next->next->offset;
}
/*
* Dummy call to list->output to give the offset to the
* listing module.
*/
list->output (offset, NULL, OUT_RAWDATA);
list->uplevel(LIST_INCBIN);
while (t--)
{
long l;
fseek (fp, base, SEEK_SET);
l = len;
while (l > 0) {
long m = fread (buf, 1, (l>sizeof(buf)?sizeof(buf):l),
fp);
if (!m) {
/*
* This shouldn't happen unless the file
* actually changes while we are reading
* it.
*/
error (ERR_NONFATAL, "`incbin': unexpected EOF while"
" reading file `%s'", fname);
t=0; /* Try to exit cleanly */
break;
}
out (offset, segment, buf, OUT_RAWDATA+m,
NO_SEG, NO_SEG);
l -= m;
}
}
list->downlevel(LIST_INCBIN);
if (instruction->times > 1) {
/*
* Dummy call to list->output to give the offset to the
* listing module.
*/
list->output (offset, NULL, OUT_RAWDATA);
list->uplevel(LIST_TIMES);
list->downlevel(LIST_TIMES);
}
fclose (fp);
return instruction->times * len;
}
return 0; /* if we're here, there's an error */
}
size_prob = FALSE;
temp = nasm_instructions[instruction->opcode];
while (temp->opcode != -1) {
int m = matches (temp, instruction);
if (m == 99)
m += jmp_match(segment, offset, bits, instruction, temp->code);
if (m == 100) /* matches! */
{
char *codes = temp->code;
long insn_size = calcsize(segment, offset, bits,
instruction, codes);
itimes = instruction->times;
if (insn_size < 0) /* shouldn't be, on pass two */
error (ERR_PANIC, "errors made it through from pass one");
else while (itimes--) {
insn_end = offset + insn_size;
for (j=0; j<instruction->nprefix; j++) {
unsigned char c=0;
switch (instruction->prefixes[j]) {
case P_LOCK:
c = 0xF0; break;
case P_REPNE: case P_REPNZ:
c = 0xF2; break;
case P_REPE: case P_REPZ: case P_REP:
c = 0xF3; break;
case R_CS: c = 0x2E; break;
case R_DS: c = 0x3E; break;
case R_ES: c = 0x26; break;
case R_FS: c = 0x64; break;
case R_GS: c = 0x65; break;
case R_SS: c = 0x36; break;
case P_A16:
if (bits != 16)
c = 0x67;
break;
case P_A32:
if (bits != 32)
c = 0x67;
break;
case P_O16:
if (bits != 16)
c = 0x66;
break;
case P_O32:
if (bits != 32)
c = 0x66;
break;
default:
error (ERR_PANIC,
"invalid instruction prefix");
}
if (c != 0) {
out (offset, segment, &c, OUT_RAWDATA+1,
NO_SEG, NO_SEG);
offset++;
}
}
gencode (segment, offset, bits, instruction, codes, insn_end);
offset += insn_size;
if (itimes > 0 && itimes == instruction->times-1) {
/*
* Dummy call to list->output to give the offset to the
* listing module.
*/
list->output (offset, NULL, OUT_RAWDATA);
list->uplevel (LIST_TIMES);
}
}
if (instruction->times > 1)
list->downlevel (LIST_TIMES);
return offset - start;
} else if (m > 0 && m > size_prob) {
size_prob = m;
}
temp++;
}
if (temp->opcode == -1) { /* didn't match any instruction */
if (size_prob == 1) /* would have matched, but for size */
error (ERR_NONFATAL, "operation size not specified");
else if (size_prob == 2)
error (ERR_NONFATAL, "mismatch in operand sizes");
else if (size_prob == 3)
error (ERR_NONFATAL, "no instruction for this cpu level");
else
error (ERR_NONFATAL,
"invalid combination of opcode and operands");
}
return 0;
}
long insn_size (long segment, long offset, int bits, unsigned long cp,
insn *instruction, efunc error)
{
struct itemplate *temp;
errfunc = error; /* to pass to other functions */
cpu = cp;
if (instruction->opcode == -1)
return 0;
if (instruction->opcode == I_DB ||
instruction->opcode == I_DW ||
instruction->opcode == I_DD ||
instruction->opcode == I_DQ ||
instruction->opcode == I_DT)
{
extop *e;
long isize, osize, wsize = 0; /* placate gcc */
isize = 0;
switch (instruction->opcode)
{
case I_DB: wsize = 1; break;
case I_DW: wsize = 2; break;
case I_DD: wsize = 4; break;
case I_DQ: wsize = 8; break;
case I_DT: wsize = 10; break;
}
for (e = instruction->eops; e; e = e->next)
{
long align;
osize = 0;
if (e->type == EOT_DB_NUMBER)
osize = 1;
else if (e->type == EOT_DB_STRING)
osize = e->stringlen;
align = (-osize) % wsize;
if (align < 0)
align += wsize;
isize += osize + align;
}
return isize * instruction->times;
}
if (instruction->opcode == I_INCBIN)
{
char fname[FILENAME_MAX];
FILE * fp;
long len;
len = FILENAME_MAX-1;
if (len > instruction->eops->stringlen)
len = instruction->eops->stringlen;
strncpy (fname, instruction->eops->stringval, len);
fname[len] = '\0';
if ( (fp = fopen(fname, "rb")) == NULL )
error (ERR_NONFATAL, "`incbin': unable to open file `%s'", fname);
else if (fseek(fp, 0L, SEEK_END) < 0)
error (ERR_NONFATAL, "`incbin': unable to seek on file `%s'",
fname);
else
{
len = ftell (fp);
fclose (fp);
if (instruction->eops->next)
{
len -= instruction->eops->next->offset;
if (instruction->eops->next->next &&
len > instruction->eops->next->next->offset)
{
len = instruction->eops->next->next->offset;
}
}
return instruction->times * len;
}
return 0; /* if we're here, there's an error */
}
temp = nasm_instructions[instruction->opcode];
while (temp->opcode != -1) {
int m = matches(temp, instruction);
if (m == 99)
m += jmp_match(segment, offset, bits, instruction, temp->code);
if (m == 100) {
/* we've matched an instruction. */
long isize;
char * codes = temp->code;
int j;
isize = calcsize(segment, offset, bits, instruction, codes);
if (isize < 0)
return -1;
for (j = 0; j < instruction->nprefix; j++)
{
if ((instruction->prefixes[j] != P_A16 &&
instruction->prefixes[j] != P_O16 && bits==16) ||
(instruction->prefixes[j] != P_A32 &&
instruction->prefixes[j] != P_O32 && bits==32))
{
isize++;
}
}
return isize * instruction->times;
}
temp++;
}
return -1; /* didn't match any instruction */
}
/* check that opn[op] is a signed byte of size 16 or 32,
and return the signed value*/
static int is_sbyte (insn *ins, int op, int size)
{
signed long v;
int ret;
ret = !(ins->forw_ref && ins->oprs[op].opflags ) && /* dead in the water on forward reference or External */
optimizing>=0 &&
/* !(ins->oprs[op].type & (BITS16|BITS32)) && */
ins->oprs[op].wrt==NO_SEG && ins->oprs[op].segment==NO_SEG;
v = ins->oprs[op].offset;
if (size==16) v = (signed short)v; /* sign extend if 16 bits */
return ret && v>=-128L && v<=127L;
}
static long calcsize (long segment, long offset, int bits,
insn *ins, char *codes)
{
long length = 0;
unsigned char c;
(void) segment; /* Don't warn that this parameter is unused */
(void) offset; /* Don't warn that this parameter is unused */
while (*codes) switch (c = *codes++) {
case 01: case 02: case 03:
codes += c, length += c; break;
case 04: case 05: case 06: case 07:
length++; break;
case 010: case 011: case 012:
codes++, length++; break;
case 017:
length++; break;
case 014: case 015: case 016:
length++; break;
case 020: case 021: case 022:
length++; break;
case 024: case 025: case 026:
length++; break;
case 030: case 031: case 032:
length += 2; break;
case 034: case 035: case 036:
length += ((ins->oprs[c-034].addr_size ?
ins->oprs[c-034].addr_size : bits) == 16 ? 2 : 4); break;
case 037:
length += 2; break;
case 040: case 041: case 042:
length += 4; break;
case 050: case 051: case 052:
length++; break;
case 060: case 061: case 062:
length += 2; break;
case 064: case 065: case 066:
length += ((ins->oprs[c-064].addr_size ?
ins->oprs[c-064].addr_size : bits) == 16 ? 2 : 4); break;
case 070: case 071: case 072:
length += 4; break;
case 0130: case 0131: case 0132:
length += is_sbyte(ins, c-0130, 16) ? 1 : 2; break;
case 0133: case 0134: case 0135:
codes+=2; length++; break;
case 0140: case 0141: case 0142:
length += is_sbyte(ins, c-0140, 32) ? 1 : 4; break;
case 0143: case 0144: case 0145:
codes+=2; length++; break;
case 0300: case 0301: case 0302:
length += chsize (&ins->oprs[c-0300], bits);
break;
case 0310:
length += (bits==32);
break;
case 0311:
length += (bits==16);
break;
case 0312:
break;
case 0320:
length += (bits==32);
break;
case 0321:
length += (bits==16);
break;
case 0322:
break;
case 0330:
codes++, length++; break;
case 0331:
case 0332:
break;
case 0333:
length++; break;
case 0340: case 0341: case 0342:
if (ins->oprs[0].segment != NO_SEG)
errfunc (ERR_NONFATAL, "attempt to reserve non-constant"
" quantity of BSS space");
else
length += ins->oprs[0].offset << (c-0340);
break;
case 0370: case 0371: case 0372:
break;
case 0373:
length++; break;
default: /* can't do it by 'case' statements */
if (c>=0100 && c<=0277) { /* it's an EA */
ea ea_data;
if (!process_ea (&ins->oprs[(c>>3)&7], &ea_data, bits, 0,
ins->forw_ref)) {
errfunc (ERR_NONFATAL, "invalid effective address");
return -1;
} else
length += ea_data.size;
} else
errfunc (ERR_PANIC, "internal instruction table corrupt"
": instruction code 0x%02X given", c);
}
return length;
}
static void gencode (long segment, long offset, int bits,
insn *ins, char *codes, long insn_end)
{
static char condval[] = { /* conditional opcodes */
0x7, 0x3, 0x2, 0x6, 0x2, 0x4, 0xF, 0xD, 0xC, 0xE, 0x6, 0x2,
0x3, 0x7, 0x3, 0x5, 0xE, 0xC, 0xD, 0xF, 0x1, 0xB, 0x9, 0x5,
0x0, 0xA, 0xA, 0xB, 0x8, 0x4
};
unsigned char c;
unsigned char bytes[4];
long data, size;
while (*codes)
switch (c = *codes++)
{
case 01: case 02: case 03:
out (offset, segment, codes, OUT_RAWDATA+c, NO_SEG, NO_SEG);
codes += c;
offset += c;
break;
case 04: case 06:
switch (ins->oprs[0].basereg)
{
case R_CS:
bytes[0] = 0x0E + (c == 0x04 ? 1 : 0); break;
case R_DS:
bytes[0] = 0x1E + (c == 0x04 ? 1 : 0); break;
case R_ES:
bytes[0] = 0x06 + (c == 0x04 ? 1 : 0); break;
case R_SS:
bytes[0] = 0x16 + (c == 0x04 ? 1 : 0); break;
default:
errfunc (ERR_PANIC, "bizarre 8086 segment register received");
}
out (offset, segment, bytes, OUT_RAWDATA+1, NO_SEG, NO_SEG);
offset++;
break;
case 05: case 07:
switch (ins->oprs[0].basereg) {
case R_FS: bytes[0] = 0xA0 + (c == 0x05 ? 1 : 0); break;
case R_GS: bytes[0] = 0xA8 + (c == 0x05 ? 1 : 0); break;
default:
errfunc (ERR_PANIC, "bizarre 386 segment register received");
}
out (offset, segment, bytes, OUT_RAWDATA+1, NO_SEG, NO_SEG);
offset++;
break;
case 010: case 011: case 012:
bytes[0] = *codes++ + regval(&ins->oprs[c-010]);
out (offset, segment, bytes, OUT_RAWDATA+1, NO_SEG, NO_SEG);
offset += 1;
break;
case 017:
bytes[0] = 0;
out (offset, segment, bytes, OUT_RAWDATA+1, NO_SEG, NO_SEG);
offset += 1;
break;
case 014: case 015: case 016:
if (ins->oprs[c-014].offset < -128
|| ins->oprs[c-014].offset > 127)
{
errfunc (ERR_WARNING, "signed byte value exceeds bounds");
}
if (ins->oprs[c-014].segment != NO_SEG)
{
data = ins->oprs[c-014].offset;
out (offset, segment, &data, OUT_ADDRESS+1,
ins->oprs[c-014].segment, ins->oprs[c-014].wrt);
}
else {
bytes[0] = ins->oprs[c-014].offset;
out (offset, segment, bytes, OUT_RAWDATA+1, NO_SEG, NO_SEG);
}
offset += 1;
break;
case 020: case 021: case 022:
if (ins->oprs[c-020].offset < -256
|| ins->oprs[c-020].offset > 255)
{
errfunc (ERR_WARNING, "byte value exceeds bounds");
}
if (ins->oprs[c-020].segment != NO_SEG) {
data = ins->oprs[c-020].offset;
out (offset, segment, &data, OUT_ADDRESS+1,
ins->oprs[c-020].segment, ins->oprs[c-020].wrt);
}
else {
bytes[0] = ins->oprs[c-020].offset;
out (offset, segment, bytes, OUT_RAWDATA+1, NO_SEG, NO_SEG);
}
offset += 1;
break;
case 024: case 025: case 026:
if (ins->oprs[c-024].offset < 0 || ins->oprs[c-024].offset > 255)
errfunc (ERR_WARNING, "unsigned byte value exceeds bounds");
if (ins->oprs[c-024].segment != NO_SEG) {
data = ins->oprs[c-024].offset;
out (offset, segment, &data, OUT_ADDRESS+1,
ins->oprs[c-024].segment, ins->oprs[c-024].wrt);
}
else {
bytes[0] = ins->oprs[c-024].offset;
out (offset, segment, bytes, OUT_RAWDATA+1, NO_SEG, NO_SEG);
}
offset += 1;
break;
case 030: case 031: case 032:
if (ins->oprs[c-030].segment == NO_SEG &&
ins->oprs[c-030].wrt == NO_SEG &&
(ins->oprs[c-030].offset < -65536L ||
ins->oprs[c-030].offset > 65535L))
{
errfunc (ERR_WARNING, "word value exceeds bounds");
}
data = ins->oprs[c-030].offset;
out (offset, segment, &data, OUT_ADDRESS+2,
ins->oprs[c-030].segment, ins->oprs[c-030].wrt);
offset += 2;
break;
case 034: case 035: case 036:
data = ins->oprs[c-034].offset;
size = ((ins->oprs[c-034].addr_size ?
ins->oprs[c-034].addr_size : bits) == 16 ? 2 : 4);
if (size==2 && (data < -65536L || data > 65535L))
errfunc (ERR_WARNING, "word value exceeds bounds");
out (offset, segment, &data, OUT_ADDRESS+size,
ins->oprs[c-034].segment, ins->oprs[c-034].wrt);
offset += size;
break;
case 037:
if (ins->oprs[0].segment == NO_SEG)
errfunc (ERR_NONFATAL, "value referenced by FAR is not"
" relocatable");
data = 0L;
out (offset, segment, &data, OUT_ADDRESS+2,
outfmt->segbase(1+ins->oprs[0].segment),
ins->oprs[0].wrt);
offset += 2;
break;
case 040: case 041: case 042:
data = ins->oprs[c-040].offset;
out (offset, segment, &data, OUT_ADDRESS+4,
ins->oprs[c-040].segment, ins->oprs[c-040].wrt);
offset += 4;
break;
case 050: case 051: case 052:
if (ins->oprs[c-050].segment != segment)
errfunc (ERR_NONFATAL, "short relative jump outside segment");
data = ins->oprs[c-050].offset - insn_end;
if (data > 127 || data < -128)
errfunc (ERR_NONFATAL, "short jump is out of range");
bytes[0] = data;
out (offset, segment, bytes, OUT_RAWDATA+1, NO_SEG, NO_SEG);
offset += 1;
break;
case 060: case 061: case 062:
if (ins->oprs[c-060].segment != segment) {
data = ins->oprs[c-060].offset;
out (offset, segment, &data, OUT_REL2ADR+insn_end-offset,
ins->oprs[c-060].segment, ins->oprs[c-060].wrt);
} else {
data = ins->oprs[c-060].offset - insn_end;
out (offset, segment, &data,
OUT_ADDRESS+2, NO_SEG, NO_SEG);
}
offset += 2;
break;
case 064: case 065: case 066:
size = ((ins->oprs[c-064].addr_size ?
ins->oprs[c-064].addr_size : bits) == 16 ? 2 : 4);
if (ins->oprs[c-064].segment != segment) {
data = ins->oprs[c-064].offset;
size = (bits == 16 ? OUT_REL2ADR : OUT_REL4ADR);
out (offset, segment, &data, size+insn_end-offset,
ins->oprs[c-064].segment, ins->oprs[c-064].wrt);
size = (bits == 16 ? 2 : 4);
} else {
data = ins->oprs[c-064].offset - insn_end;
out (offset, segment, &data,
OUT_ADDRESS+size, NO_SEG, NO_SEG);
}
offset += size;
break;
case 070: case 071: case 072:
if (ins->oprs[c-070].segment != segment) {
data = ins->oprs[c-070].offset;
out (offset, segment, &data, OUT_REL4ADR+insn_end-offset,
ins->oprs[c-070].segment, ins->oprs[c-070].wrt);
} else {
data = ins->oprs[c-070].offset - insn_end;
out (offset, segment, &data,
OUT_ADDRESS+4, NO_SEG, NO_SEG);
}
offset += 4;
break;
case 0130: case 0131: case 0132:
data = ins->oprs[c-0130].offset;
if (is_sbyte(ins, c-0130, 16)) {
out (offset, segment, &data, OUT_RAWDATA+1, NO_SEG, NO_SEG);
offset++;
} else {
if (ins->oprs[c-0130].segment == NO_SEG &&
ins->oprs[c-0130].wrt == NO_SEG &&
(data < -65536L || data > 65535L)) {
errfunc (ERR_WARNING, "word value exceeds bounds");
}
out (offset, segment, &data, OUT_ADDRESS+2,
ins->oprs[c-0130].segment, ins->oprs[c-0130].wrt);
offset += 2;
}
break;
case 0133: case 0134: case 0135:
codes++;
bytes[0] = *codes++;
if (is_sbyte(ins, c-0133, 16)) bytes[0] |= 2; /* s-bit */
out (offset, segment, bytes, OUT_RAWDATA+1, NO_SEG, NO_SEG);
offset++;
break;
case 0140: case 0141: case 0142:
data = ins->oprs[c-0140].offset;
if (is_sbyte(ins, c-0140, 32)) {
out (offset, segment, &data, OUT_RAWDATA+1, NO_SEG, NO_SEG);
offset++;
} else {
out (offset, segment, &data, OUT_ADDRESS+4,
ins->oprs[c-0140].segment, ins->oprs[c-0140].wrt);
offset += 4;
}
break;
case 0143: case 0144: case 0145:
codes++;
bytes[0] = *codes++;
if (is_sbyte(ins, c-0143, 32)) bytes[0] |= 2; /* s-bit */
out (offset, segment, bytes, OUT_RAWDATA+1, NO_SEG, NO_SEG);
offset++;
break;
case 0300: case 0301: case 0302:
if (chsize (&ins->oprs[c-0300], bits)) {
*bytes = 0x67;
out (offset, segment, bytes,
OUT_RAWDATA+1, NO_SEG, NO_SEG);
offset += 1;
} else
offset += 0;
break;
case 0310:
if (bits==32) {
*bytes = 0x67;
out (offset, segment, bytes,
OUT_RAWDATA+1, NO_SEG, NO_SEG);
offset += 1;
} else
offset += 0;
break;
case 0311:
if (bits==16) {
*bytes = 0x67;
out (offset, segment, bytes,
OUT_RAWDATA+1, NO_SEG, NO_SEG);
offset += 1;
} else
offset += 0;
break;
case 0312:
break;
case 0320:
if (bits==32) {
*bytes = 0x66;
out (offset, segment, bytes,
OUT_RAWDATA+1, NO_SEG, NO_SEG);
offset += 1;
} else
offset += 0;
break;
case 0321:
if (bits==16) {
*bytes = 0x66;
out (offset, segment, bytes,
OUT_RAWDATA+1, NO_SEG, NO_SEG);
offset += 1;
} else
offset += 0;
break;
case 0322:
break;
case 0330:
*bytes = *codes++ ^ condval[ins->condition];
out (offset, segment, bytes,
OUT_RAWDATA+1, NO_SEG, NO_SEG);
offset += 1;
break;
case 0331:
case 0332:
break;
case 0333:
*bytes = 0xF3;
out (offset, segment, bytes,
OUT_RAWDATA+1, NO_SEG, NO_SEG);
offset += 1;
break;
case 0340: case 0341: case 0342:
if (ins->oprs[0].segment != NO_SEG)
errfunc (ERR_PANIC, "non-constant BSS size in pass two");
else {
long size = ins->oprs[0].offset << (c-0340);
if (size > 0)
out (offset, segment, NULL,
OUT_RESERVE+size, NO_SEG, NO_SEG);
offset += size;
}
break;
case 0370: case 0371: case 0372:
break;
case 0373:
*bytes = bits==16 ? 3 : 5;
out (offset, segment, bytes,
OUT_RAWDATA+1, NO_SEG, NO_SEG);
offset += 1;
break;
default: /* can't do it by 'case' statements */
if (c>=0100 && c<=0277) { /* it's an EA */
ea ea_data;
int rfield;
unsigned char *p;
long s;
if (c<=0177) /* pick rfield from operand b */
rfield = regval (&ins->oprs[c&7]);
else /* rfield is constant */
rfield = c & 7;
if (!process_ea (&ins->oprs[(c>>3)&7], &ea_data, bits, rfield,
ins->forw_ref))
{
errfunc (ERR_NONFATAL, "invalid effective address");
}
p = bytes;
*p++ = ea_data.modrm;
if (ea_data.sib_present)
*p++ = ea_data.sib;
s = p-bytes;
out (offset, segment, bytes, OUT_RAWDATA + s,
NO_SEG, NO_SEG);
switch (ea_data.bytes) {
case 0:
break;
case 1:
if (ins->oprs[(c>>3)&7].segment != NO_SEG) {
data = ins->oprs[(c>>3)&7].offset;
out (offset, segment, &data, OUT_ADDRESS+1,
ins->oprs[(c>>3)&7].segment,
ins->oprs[(c>>3)&7].wrt);
} else {
*bytes = ins->oprs[(c>>3)&7].offset;
out (offset, segment, bytes, OUT_RAWDATA+1,
NO_SEG, NO_SEG);
}
s++;
break;
case 2:
case 4:
data = ins->oprs[(c>>3)&7].offset;
out (offset, segment, &data,
OUT_ADDRESS+ea_data.bytes,
ins->oprs[(c>>3)&7].segment, ins->oprs[(c>>3)&7].wrt);
s += ea_data.bytes;
break;
}
offset += s;
} else
errfunc (ERR_PANIC, "internal instruction table corrupt"
": instruction code 0x%02X given", c);
}
}
static int regval (operand *o)
{
switch (o->basereg) {
case R_EAX: case R_AX: case R_AL: case R_ES: case R_CR0: case R_DR0:
case R_ST0: case R_MM0: case R_XMM0:
return 0;
case R_ECX: case R_CX: case R_CL: case R_CS: case R_DR1: case R_ST1:
case R_MM1: case R_XMM1:
return 1;
case R_EDX: case R_DX: case R_DL: case R_SS: case R_CR2: case R_DR2:
case R_ST2: case R_MM2: case R_XMM2:
return 2;
case R_EBX: case R_BX: case R_BL: case R_DS: case R_CR3: case R_DR3:
case R_TR3: case R_ST3: case R_MM3: case R_XMM3:
return 3;
case R_ESP: case R_SP: case R_AH: case R_FS: case R_CR4: case R_TR4:
case R_ST4: case R_MM4: case R_XMM4:
return 4;
case R_EBP: case R_BP: case R_CH: case R_GS: case R_TR5: case R_ST5:
case R_MM5: case R_XMM5:
return 5;
case R_ESI: case R_SI: case R_DH: case R_DR6: case R_TR6: case R_ST6:
case R_MM6: case R_XMM6:
return 6;
case R_EDI: case R_DI: case R_BH: case R_DR7: case R_TR7: case R_ST7:
case R_MM7: case R_XMM7:
return 7;
default: /* panic */
errfunc (ERR_PANIC, "invalid register operand given to regval()");
return 0;
}
}
static int matches (struct itemplate *itemp, insn *instruction)
{
int i, size[3], asize, oprs, ret;
ret = 100;
/*
* Check the opcode
*/
if (itemp->opcode != instruction->opcode) return 0;
/*
* Count the operands
*/
if (itemp->operands != instruction->operands) return 0;
/*
* Check that no spurious colons or TOs are present
*/
for (i=0; i<itemp->operands; i++)
if (instruction->oprs[i].type & ~itemp->opd[i] & (COLON|TO))
return 0;
/*
* Check that the operand flags all match up
*/
for (i=0; i<itemp->operands; i++)
if (itemp->opd[i] & ~instruction->oprs[i].type ||
((itemp->opd[i] & SIZE_MASK) &&
((itemp->opd[i] ^ instruction->oprs[i].type) & SIZE_MASK)))
{
if ((itemp->opd[i] & ~instruction->oprs[i].type & NON_SIZE) ||
(instruction->oprs[i].type & SIZE_MASK))
return 0;
else
/* ret = 1; */
return 1;
}
/*
* Check operand sizes
*/
if (itemp->flags & IF_ARMASK) {
size[0] = size[1] = size[2] = 0;
switch (itemp->flags & IF_ARMASK) {
case IF_AR0: i = 0; break;
case IF_AR1: i = 1; break;
case IF_AR2: i = 2; break;
default: break; /* Shouldn't happen */
}
if (itemp->flags & IF_SB) {
size[i] = BITS8;
} else if (itemp->flags & IF_SW) {
size[i] = BITS16;
} else if (itemp->flags & IF_SD) {
size[i] = BITS32;
}
} else {
asize = 0;
if (itemp->flags & IF_SB) {
asize = BITS8;
oprs = itemp->operands;
} else if (itemp->flags & IF_SW) {
asize = BITS16;
oprs = itemp->operands;
} else if (itemp->flags & IF_SD) {
asize = BITS32;
oprs = itemp->operands;
}
size[0] = size[1] = size[2] = asize;
}
if (itemp->flags & (IF_SM | IF_SM2)) {
oprs = (itemp->flags & IF_SM2 ? 2 : itemp->operands);
asize = 0;
for (i=0; i<oprs; i++) {
if ( (asize = itemp->opd[i] & SIZE_MASK) != 0) {
int j;
for (j=0; j<oprs; j++)
size[j] = asize;
break;
}
}
} else {
oprs = itemp->operands;
}
for (i=0; i<itemp->operands; i++)
if (!(itemp->opd[i] & SIZE_MASK) &&
(instruction->oprs[i].type & SIZE_MASK & ~size[i]))
/* ret = 2; */
return 2;
/*
* Check template is okay at the set cpu level
*/
if ((itemp->flags & IF_PLEVEL) > cpu) return 3;
/*
* Check if special handling needed for Jumps
*/
if ((unsigned char)(itemp->code[0]) >= 0370) return 99;
return ret;
}
static ea *process_ea (operand *input, ea *output, int addrbits, int rfield,
int forw_ref)
{
if (!(REGISTER & ~input->type)) { /* it's a single register */
static int regs[] = {
R_AL, R_CL, R_DL, R_BL, R_AH, R_CH, R_DH, R_BH,
R_AX, R_CX, R_DX, R_BX, R_SP, R_BP, R_SI, R_DI,
R_EAX, R_ECX, R_EDX, R_EBX, R_ESP, R_EBP, R_ESI, R_EDI,
R_MM0, R_MM1, R_MM2, R_MM3, R_MM4, R_MM5, R_MM6, R_MM7,
R_XMM0, R_XMM1, R_XMM2, R_XMM3, R_XMM4, R_XMM5, R_XMM6, R_XMM7
};
int i;
for (i=0; i<elements(regs); i++)
if (input->basereg == regs[i]) break;
if (i<elements(regs)) {
output->sib_present = FALSE;/* no SIB necessary */
output->bytes = 0; /* no offset necessary either */
output->modrm = 0xC0 | (rfield << 3) | (i & 7);
}
else
return NULL;
} else { /* it's a memory reference */
if (input->basereg==-1 && (input->indexreg==-1 || input->scale==0)) {
/* it's a pure offset */
if (input->addr_size)
addrbits = input->addr_size;
output->sib_present = FALSE;
output->bytes = (addrbits==32 ? 4 : 2);
output->modrm = (addrbits==32 ? 5 : 6) | (rfield << 3);
}
else { /* it's an indirection */
int i=input->indexreg, b=input->basereg, s=input->scale;
long o=input->offset, seg=input->segment;
int hb=input->hintbase, ht=input->hinttype;
int t;
if (s==0) i = -1; /* make this easy, at least */
if (i==R_EAX || i==R_EBX || i==R_ECX || i==R_EDX
|| i==R_EBP || i==R_ESP || i==R_ESI || i==R_EDI
|| b==R_EAX || b==R_EBX || b==R_ECX || b==R_EDX
|| b==R_EBP || b==R_ESP || b==R_ESI || b==R_EDI) {
/* it must be a 32-bit memory reference. Firstly we have
* to check that all registers involved are type Exx. */
if (i!=-1 && i!=R_EAX && i!=R_EBX && i!=R_ECX && i!=R_EDX
&& i!=R_EBP && i!=R_ESP && i!=R_ESI && i!=R_EDI)
return NULL;
if (b!=-1 && b!=R_EAX && b!=R_EBX && b!=R_ECX && b!=R_EDX
&& b!=R_EBP && b!=R_ESP && b!=R_ESI && b!=R_EDI)
return NULL;
/* While we're here, ensure the user didn't specify WORD. */
if (input->addr_size == 16)
return NULL;
/* now reorganise base/index */
if (s == 1 && b != i && b != -1 && i != -1 &&
((hb==b&&ht==EAH_NOTBASE) || (hb==i&&ht==EAH_MAKEBASE)))
t = b, b = i, i = t; /* swap if hints say so */
if (b==i) /* convert EAX+2*EAX to 3*EAX */
b = -1, s++;
if (b==-1 && s==1 && !(hb == i && ht == EAH_NOTBASE))
b = i, i = -1; /* make single reg base, unless hint */
if (((s==2 && i!=R_ESP && !(input->eaflags & EAF_TIMESTWO)) ||
s==3 || s==5 || s==9) && b==-1)
b = i, s--; /* convert 3*EAX to EAX+2*EAX */
if (s==1 && i==R_ESP) /* swap ESP into base if scale is 1 */
i = b, b = R_ESP;
if (i==R_ESP || (s!=1 && s!=2 && s!=4 && s!=8 && i!=-1))
return NULL; /* wrong, for various reasons */
if (i==-1 && b!=R_ESP) {/* no SIB needed */
int mod, rm;
switch(b) {
case R_EAX: rm = 0; break;
case R_ECX: rm = 1; break;
case R_EDX: rm = 2; break;
case R_EBX: rm = 3; break;
case R_EBP: rm = 5; break;
case R_ESI: rm = 6; break;
case R_EDI: rm = 7; break;
case -1: rm = 5; break;
default: /* should never happen */
return NULL;
}
if (b==-1 || (b!=R_EBP && o==0 &&
seg==NO_SEG && !forw_ref &&
!(input->eaflags &
(EAF_BYTEOFFS|EAF_WORDOFFS))))
mod = 0;
else if (input->eaflags & EAF_BYTEOFFS ||
(o>=-128 && o<=127 && seg==NO_SEG && !forw_ref &&
!(input->eaflags & EAF_WORDOFFS))) {
mod = 1;
}
else
mod = 2;
output->sib_present = FALSE;
output->bytes = (b==-1 || mod==2 ? 4 : mod);
output->modrm = (mod<<6) | (rfield<<3) | rm;
}
else { /* we need a SIB */
int mod, scale, index, base;
switch (b) {
case R_EAX: base = 0; break;
case R_ECX: base = 1; break;
case R_EDX: base = 2; break;
case R_EBX: base = 3; break;
case R_ESP: base = 4; break;
case R_EBP: case -1: base = 5; break;
case R_ESI: base = 6; break;
case R_EDI: base = 7; break;
default: /* then what the smeg is it? */
return NULL; /* panic */
}
switch (i) {
case R_EAX: index = 0; break;
case R_ECX: index = 1; break;
case R_EDX: index = 2; break;
case R_EBX: index = 3; break;
case -1: index = 4; break;
case R_EBP: index = 5; break;
case R_ESI: index = 6; break;
case R_EDI: index = 7; break;
default: /* then what the smeg is it? */
return NULL; /* panic */
}
if (i==-1) s = 1;
switch (s) {
case 1: scale = 0; break;
case 2: scale = 1; break;
case 4: scale = 2; break;
case 8: scale = 3; break;
default: /* then what the smeg is it? */
return NULL; /* panic */
}
if (b==-1 || (b!=R_EBP && o==0 &&
seg==NO_SEG && !forw_ref &&
!(input->eaflags &
(EAF_BYTEOFFS|EAF_WORDOFFS))))
mod = 0;
else if (input->eaflags & EAF_BYTEOFFS ||
(o>=-128 && o<=127 && seg==NO_SEG && !forw_ref &&
!(input->eaflags & EAF_WORDOFFS)))
mod = 1;
else
mod = 2;
output->sib_present = TRUE;
output->bytes = (b==-1 || mod==2 ? 4 : mod);
output->modrm = (mod<<6) | (rfield<<3) | 4;
output->sib = (scale<<6) | (index<<3) | base;
}
}
else { /* it's 16-bit */
int mod, rm;
/* check all registers are BX, BP, SI or DI */
if ((b!=-1 && b!=R_BP && b!=R_BX && b!=R_SI && b!=R_DI) ||
(i!=-1 && i!=R_BP && i!=R_BX && i!=R_SI && i!=R_DI))
return NULL;
/* ensure the user didn't specify DWORD */
if (input->addr_size == 32)
return NULL;
if (s!=1 && i!=-1) return NULL;/* no can do, in 16-bit EA */
if (b==-1 && i!=-1) b ^= i ^= b ^= i; /* swap them round */
if ((b==R_SI || b==R_DI) && i!=-1)
b ^= i ^= b ^= i; /* have BX/BP as base, SI/DI index */
if (b==i) return NULL;/* shouldn't ever happen, in theory */
if (i!=-1 && b!=-1 &&
(i==R_BP || i==R_BX || b==R_SI || b==R_DI))
return NULL; /* invalid combinations */
if (b==-1) /* pure offset: handled above */
return NULL; /* so if it gets to here, panic! */
rm = -1;
if (i!=-1)
switch (i*256 + b) {
case R_SI*256+R_BX: rm=0; break;
case R_DI*256+R_BX: rm=1; break;
case R_SI*256+R_BP: rm=2; break;
case R_DI*256+R_BP: rm=3; break;
}
else
switch (b) {
case R_SI: rm=4; break;
case R_DI: rm=5; break;
case R_BP: rm=6; break;
case R_BX: rm=7; break;
}
if (rm==-1) /* can't happen, in theory */
return NULL; /* so panic if it does */
if (o==0 && seg==NO_SEG && !forw_ref && rm!=6 &&
!(input->eaflags & (EAF_BYTEOFFS|EAF_WORDOFFS)))
mod = 0;
else if (input->eaflags & EAF_BYTEOFFS ||
(o>=-128 && o<=127 && seg==NO_SEG && !forw_ref &&
!(input->eaflags & EAF_WORDOFFS)))
mod = 1;
else
mod = 2;
output->sib_present = FALSE; /* no SIB - it's 16-bit */
output->bytes = mod; /* bytes of offset needed */
output->modrm = (mod<<6) | (rfield<<3) | rm;
}
}
}
output->size = 1 + output->sib_present + output->bytes;
return output;
}
static int chsize (operand *input, int addrbits)
{
if (!(MEMORY & ~input->type)) {
int i=input->indexreg, b=input->basereg;
if (input->scale==0) i = -1;
if (i == -1 && b == -1) /* pure offset */
return (input->addr_size != 0 && input->addr_size != addrbits);
if (i==R_EAX || i==R_EBX || i==R_ECX || i==R_EDX
|| i==R_EBP || i==R_ESP || i==R_ESI || i==R_EDI
|| b==R_EAX || b==R_EBX || b==R_ECX || b==R_EDX
|| b==R_EBP || b==R_ESP || b==R_ESI || b==R_EDI)
return (addrbits==16);
else
return (addrbits==32);
}
else
return 0;
}
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