mirror/nasm
2
0
Fork 0
mirror of https://github.com/netwide-assembler/nasm.git synced 2025-01-24 16:35:40 +08:00
Code Issues Packages Projects Releases Wiki Activity
2be1050f93
nasm/eval.c
H. Peter Anvin cd7893d02d Remove additional function pointers that never change 
Remove additional cached function pointers which point to static
variables which are never actually changed.  Just refer to the global
variable instead.

Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2016-02-18 01:25:46 -08:00

1017 lines
28 KiB
C
Raw Blame History

/* ----------------------------------------------------------------------- *
*
* Copyright 1996-2016 The NASM Authors - All Rights Reserved
* See the file AUTHORS included with the NASM distribution for
* the specific copyright holders.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following
* conditions are met:
*
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above
* copyright notice, this list of conditions and the following
* disclaimer in the documentation and/or other materials provided
* with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
* CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
* INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
* OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
* EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* ----------------------------------------------------------------------- */
/*
* eval.c expression evaluator for the Netwide Assembler
*/
#include "compiler.h"
#include <stdio.h>
#include <stdlib.h>
#include <stddef.h>
#include <string.h>
#include <ctype.h>
#include <inttypes.h>
#include "nasm.h"
#include "nasmlib.h"
#include "eval.h"
#include "labels.h"
#include "float.h"
#define TEMPEXPRS_DELTA 128
#define TEMPEXPR_DELTA 8
static scanner scan; /* Address of scanner routine */
static expr **tempexprs = NULL;
static int ntempexprs;
static int tempexprs_size = 0;
static expr *tempexpr;
static int ntempexpr;
static int tempexpr_size;
static struct tokenval *tokval; /* The current token */
static int i; /* The t_type of tokval */
static void *scpriv;
static int *opflags;
static struct eval_hints *hint;
extern int in_abs_seg; /* ABSOLUTE segment flag */
extern int32_t abs_seg; /* ABSOLUTE segment */
extern int32_t abs_offset; /* ABSOLUTE segment offset */
/*
* Unimportant cleanup is done to avoid confusing people who are trying
* to debug real memory leaks
*/
void eval_cleanup(void)
{
while (ntempexprs)
nasm_free(tempexprs[--ntempexprs]);
nasm_free(tempexprs);
}
/*
* Construct a temporary expression.
*/
static void begintemp(void)
{
tempexpr = NULL;
tempexpr_size = ntempexpr = 0;
}
static void addtotemp(int32_t type, int64_t value)
{
while (ntempexpr >= tempexpr_size) {
tempexpr_size += TEMPEXPR_DELTA;
tempexpr = nasm_realloc(tempexpr,
tempexpr_size * sizeof(*tempexpr));
}
tempexpr[ntempexpr].type = type;
tempexpr[ntempexpr++].value = value;
}
static expr *finishtemp(void)
{
addtotemp(0L, 0L); /* terminate */
while (ntempexprs >= tempexprs_size) {
tempexprs_size += TEMPEXPRS_DELTA;
tempexprs = nasm_realloc(tempexprs,
tempexprs_size * sizeof(*tempexprs));
}
return tempexprs[ntempexprs++] = tempexpr;
}
/*
* Add two vector datatypes. We have some bizarre behaviour on far-
* absolute segment types: we preserve them during addition _only_
* if one of the segments is a truly pure scalar.
*/
static expr *add_vectors(expr * p, expr * q)
{
int preserve;
preserve = is_really_simple(p) || is_really_simple(q);
begintemp();
while (p->type && q->type &&
p->type < EXPR_SEGBASE + SEG_ABS &&
q->type < EXPR_SEGBASE + SEG_ABS) {
int lasttype;
if (p->type > q->type) {
addtotemp(q->type, q->value);
lasttype = q++->type;
} else if (p->type < q->type) {
addtotemp(p->type, p->value);
lasttype = p++->type;
} else { /* *p and *q have same type */
int64_t sum = p->value + q->value;
if (sum) {
addtotemp(p->type, sum);
if (hint)
hint->type = EAH_SUMMED;
}
lasttype = p->type;
p++, q++;
}
if (lasttype == EXPR_UNKNOWN) {
return finishtemp();
}
}
while (p->type && (preserve || p->type < EXPR_SEGBASE + SEG_ABS)) {
addtotemp(p->type, p->value);
p++;
}
while (q->type && (preserve || q->type < EXPR_SEGBASE + SEG_ABS)) {
addtotemp(q->type, q->value);
q++;
}
return finishtemp();
}
/*
* Multiply a vector by a scalar. Strip far-absolute segment part
* if present.
*
* Explicit treatment of UNKNOWN is not required in this routine,
* since it will silently do the Right Thing anyway.
*
* If `affect_hints' is set, we also change the hint type to
* NOTBASE if a MAKEBASE hint points at a register being
* multiplied. This allows [eax*1+ebx] to hint EBX rather than EAX
* as the base register.
*/
static expr *scalar_mult(expr * vect, int64_t scalar, int affect_hints)
{
expr *p = vect;
while (p->type && p->type < EXPR_SEGBASE + SEG_ABS) {
p->value = scalar * (p->value);
if (hint && hint->type == EAH_MAKEBASE &&
p->type == hint->base && affect_hints)
hint->type = EAH_NOTBASE;
p++;
}
p->type = 0;
return vect;
}
static expr *scalarvect(int64_t scalar)
{
begintemp();
addtotemp(EXPR_SIMPLE, scalar);
return finishtemp();
}
static expr *unknown_expr(void)
{
begintemp();
addtotemp(EXPR_UNKNOWN, 1L);
return finishtemp();
}
/*
* The SEG operator: calculate the segment part of a relocatable
* value. Return NULL, as usual, if an error occurs. Report the
* error too.
*/
static expr *segment_part(expr * e)
{
int32_t seg;
if (is_unknown(e))
return unknown_expr();
if (!is_reloc(e)) {
nasm_error(ERR_NONFATAL, "cannot apply SEG to a non-relocatable value");
return NULL;
}
seg = reloc_seg(e);
if (seg == NO_SEG) {
nasm_error(ERR_NONFATAL, "cannot apply SEG to a non-relocatable value");
return NULL;
} else if (seg & SEG_ABS) {
return scalarvect(seg & ~SEG_ABS);
} else if (seg & 1) {
nasm_error(ERR_NONFATAL, "SEG applied to something which"
" is already a segment base");
return NULL;
} else {
int32_t base = ofmt->segbase(seg + 1);
begintemp();
addtotemp((base == NO_SEG ? EXPR_UNKNOWN : EXPR_SEGBASE + base),
1L);
return finishtemp();
}
}
/*
* Recursive-descent parser. Called with a single boolean operand,
* which is true if the evaluation is critical (i.e. unresolved
* symbols are an error condition). Must update the global `i' to
* reflect the token after the parsed string. May return NULL.
*
* evaluate() should report its own errors: on return it is assumed
* that if NULL has been returned, the error has already been
* reported.
*/
/*
* Grammar parsed is:
*
* expr : bexpr [ WRT expr6 ]
* bexpr : rexp0 or expr0 depending on relative-mode setting
* rexp0 : rexp1 [ {||} rexp1...]
* rexp1 : rexp2 [ {^^} rexp2...]
* rexp2 : rexp3 [ {&&} rexp3...]
* rexp3 : expr0 [ {=,==,<>,!=,<,>,<=,>=} expr0 ]
* expr0 : expr1 [ {|} expr1...]
* expr1 : expr2 [ {^} expr2...]
* expr2 : expr3 [ {&} expr3...]
* expr3 : expr4 [ {<<,>>} expr4...]
* expr4 : expr5 [ {+,-} expr5...]
* expr5 : expr6 [ {*,/,%,//,%%} expr6...]
* expr6 : { ~,+,-,IFUNC,SEG } expr6
* | (bexpr)
* | symbol
* | $
* | number
*/
static expr *rexp0(int), *rexp1(int), *rexp2(int), *rexp3(int);
static expr *expr0(int), *expr1(int), *expr2(int), *expr3(int);
static expr *expr4(int), *expr5(int), *expr6(int);
static expr *(*bexpr) (int);
static expr *rexp0(int critical)
{
expr *e, *f;
e = rexp1(critical);
if (!e)
return NULL;
while (i == TOKEN_DBL_OR) {
i = scan(scpriv, tokval);
f = rexp1(critical);
if (!f)
return NULL;
if (!(is_simple(e) || is_just_unknown(e)) ||
!(is_simple(f) || is_just_unknown(f))) {
nasm_error(ERR_NONFATAL, "`|' operator may only be applied to"
" scalar values");
}
if (is_just_unknown(e) || is_just_unknown(f))
e = unknown_expr();
else
e = scalarvect((int64_t)(reloc_value(e) || reloc_value(f)));
}
return e;
}
static expr *rexp1(int critical)
{
expr *e, *f;
e = rexp2(critical);
if (!e)
return NULL;
while (i == TOKEN_DBL_XOR) {
i = scan(scpriv, tokval);
f = rexp2(critical);
if (!f)
return NULL;
if (!(is_simple(e) || is_just_unknown(e)) ||
!(is_simple(f) || is_just_unknown(f))) {
nasm_error(ERR_NONFATAL, "`^' operator may only be applied to"
" scalar values");
}
if (is_just_unknown(e) || is_just_unknown(f))
e = unknown_expr();
else
e = scalarvect((int64_t)(!reloc_value(e) ^ !reloc_value(f)));
}
return e;
}
static expr *rexp2(int critical)
{
expr *e, *f;
e = rexp3(critical);
if (!e)
return NULL;
while (i == TOKEN_DBL_AND) {
i = scan(scpriv, tokval);
f = rexp3(critical);
if (!f)
return NULL;
if (!(is_simple(e) || is_just_unknown(e)) ||
!(is_simple(f) || is_just_unknown(f))) {
nasm_error(ERR_NONFATAL, "`&' operator may only be applied to"
" scalar values");
}
if (is_just_unknown(e) || is_just_unknown(f))
e = unknown_expr();
else
e = scalarvect((int64_t)(reloc_value(e) && reloc_value(f)));
}
return e;
}
static expr *rexp3(int critical)
{
expr *e, *f;
int64_t v;
e = expr0(critical);
if (!e)
return NULL;
while (i == TOKEN_EQ || i == TOKEN_LT || i == TOKEN_GT ||
i == TOKEN_NE || i == TOKEN_LE || i == TOKEN_GE) {
int j = i;
i = scan(scpriv, tokval);
f = expr0(critical);
if (!f)
return NULL;
e = add_vectors(e, scalar_mult(f, -1L, false));
switch (j) {
case TOKEN_EQ:
case TOKEN_NE:
if (is_unknown(e))
v = -1; /* means unknown */
else if (!is_really_simple(e) || reloc_value(e) != 0)
v = (j == TOKEN_NE); /* unequal, so return true if NE */
else
v = (j == TOKEN_EQ); /* equal, so return true if EQ */
break;
default:
if (is_unknown(e))
v = -1; /* means unknown */
else if (!is_really_simple(e)) {
nasm_error(ERR_NONFATAL,
"`%s': operands differ by a non-scalar",
(j == TOKEN_LE ? "<=" : j == TOKEN_LT ? "<" : j ==
TOKEN_GE ? ">=" : ">"));
v = 0; /* must set it to _something_ */
} else {
int64_t vv = reloc_value(e);
if (vv == 0)
v = (j == TOKEN_LE || j == TOKEN_GE);
else if (vv > 0)
v = (j == TOKEN_GE || j == TOKEN_GT);
else /* vv < 0 */
v = (j == TOKEN_LE || j == TOKEN_LT);
}
break;
}
if (v == -1)
e = unknown_expr();
else
e = scalarvect(v);
}
return e;
}
static expr *expr0(int critical)
{
expr *e, *f;
e = expr1(critical);
if (!e)
return NULL;
while (i == '|') {
i = scan(scpriv, tokval);
f = expr1(critical);
if (!f)
return NULL;
if (!(is_simple(e) || is_just_unknown(e)) ||
!(is_simple(f) || is_just_unknown(f))) {
nasm_error(ERR_NONFATAL, "`|' operator may only be applied to"
" scalar values");
}
if (is_just_unknown(e) || is_just_unknown(f))
e = unknown_expr();
else
e = scalarvect(reloc_value(e) | reloc_value(f));
}
return e;
}
static expr *expr1(int critical)
{
expr *e, *f;
e = expr2(critical);
if (!e)
return NULL;
while (i == '^') {
i = scan(scpriv, tokval);
f = expr2(critical);
if (!f)
return NULL;
if (!(is_simple(e) || is_just_unknown(e)) ||
!(is_simple(f) || is_just_unknown(f))) {
nasm_error(ERR_NONFATAL, "`^' operator may only be applied to"
" scalar values");
}
if (is_just_unknown(e) || is_just_unknown(f))
e = unknown_expr();
else
e = scalarvect(reloc_value(e) ^ reloc_value(f));
}
return e;
}
static expr *expr2(int critical)
{
expr *e, *f;
e = expr3(critical);
if (!e)
return NULL;
while (i == '&') {
i = scan(scpriv, tokval);
f = expr3(critical);
if (!f)
return NULL;
if (!(is_simple(e) || is_just_unknown(e)) ||
!(is_simple(f) || is_just_unknown(f))) {
nasm_error(ERR_NONFATAL, "`&' operator may only be applied to"
" scalar values");
}
if (is_just_unknown(e) || is_just_unknown(f))
e = unknown_expr();
else
e = scalarvect(reloc_value(e) & reloc_value(f));
}
return e;
}
static expr *expr3(int critical)
{
expr *e, *f;
e = expr4(critical);
if (!e)
return NULL;
while (i == TOKEN_SHL || i == TOKEN_SHR) {
int j = i;
i = scan(scpriv, tokval);
f = expr4(critical);
if (!f)
return NULL;
if (!(is_simple(e) || is_just_unknown(e)) ||
!(is_simple(f) || is_just_unknown(f))) {
nasm_error(ERR_NONFATAL, "shift operator may only be applied to"
" scalar values");
} else if (is_just_unknown(e) || is_just_unknown(f)) {
e = unknown_expr();
} else
switch (j) {
case TOKEN_SHL:
e = scalarvect(reloc_value(e) << reloc_value(f));
break;
case TOKEN_SHR:
e = scalarvect(((uint64_t)reloc_value(e)) >>
reloc_value(f));
break;
}
}
return e;
}
static expr *expr4(int critical)
{
expr *e, *f;
e = expr5(critical);
if (!e)
return NULL;
while (i == '+' || i == '-') {
int j = i;
i = scan(scpriv, tokval);
f = expr5(critical);
if (!f)
return NULL;
switch (j) {
case '+':
e = add_vectors(e, f);
break;
case '-':
e = add_vectors(e, scalar_mult(f, -1L, false));
break;
}
}
return e;
}
static expr *expr5(int critical)
{
expr *e, *f;
e = expr6(critical);
if (!e)
return NULL;
while (i == '*' || i == '/' || i == '%' ||
i == TOKEN_SDIV || i == TOKEN_SMOD) {
int j = i;
i = scan(scpriv, tokval);
f = expr6(critical);
if (!f)
return NULL;
if (j != '*' && (!(is_simple(e) || is_just_unknown(e)) ||
!(is_simple(f) || is_just_unknown(f)))) {
nasm_error(ERR_NONFATAL, "division operator may only be applied to"
" scalar values");
return NULL;
}
if (j != '*' && !is_unknown(f) && reloc_value(f) == 0) {
nasm_error(ERR_NONFATAL, "division by zero");
return NULL;
}
switch (j) {
case '*':
if (is_simple(e))
e = scalar_mult(f, reloc_value(e), true);
else if (is_simple(f))
e = scalar_mult(e, reloc_value(f), true);
else if (is_just_unknown(e) && is_just_unknown(f))
e = unknown_expr();
else {
nasm_error(ERR_NONFATAL, "unable to multiply two "
"non-scalar objects");
return NULL;
}
break;
case '/':
if (is_just_unknown(e) || is_just_unknown(f))
e = unknown_expr();
else
e = scalarvect(((uint64_t)reloc_value(e)) /
((uint64_t)reloc_value(f)));
break;
case '%':
if (is_just_unknown(e) || is_just_unknown(f))
e = unknown_expr();
else
e = scalarvect(((uint64_t)reloc_value(e)) %
((uint64_t)reloc_value(f)));
break;
case TOKEN_SDIV:
if (is_just_unknown(e) || is_just_unknown(f))
e = unknown_expr();
else
e = scalarvect(((int64_t)reloc_value(e)) /
((int64_t)reloc_value(f)));
break;
case TOKEN_SMOD:
if (is_just_unknown(e) || is_just_unknown(f))
e = unknown_expr();
else
e = scalarvect(((int64_t)reloc_value(e)) %
((int64_t)reloc_value(f)));
break;
}
}
return e;
}
static expr *eval_floatize(enum floatize type)
{
uint8_t result[16], *p; /* Up to 128 bits */
static const struct {
int bytes, start, len;
} formats[] = {
{ 1, 0, 1 }, /* FLOAT_8 */
{ 2, 0, 2 }, /* FLOAT_16 */
{ 4, 0, 4 }, /* FLOAT_32 */
{ 8, 0, 8 }, /* FLOAT_64 */
{ 10, 0, 8 }, /* FLOAT_80M */
{ 10, 8, 2 }, /* FLOAT_80E */
{ 16, 0, 8 }, /* FLOAT_128L */
{ 16, 8, 8 }, /* FLOAT_128H */
};
int sign = 1;
int64_t val;
int j;
i = scan(scpriv, tokval);
if (i != '(') {
nasm_error(ERR_NONFATAL, "expecting `('");
return NULL;
}
i = scan(scpriv, tokval);
if (i == '-' || i == '+') {
sign = (i == '-') ? -1 : 1;
i = scan(scpriv, tokval);
}
if (i != TOKEN_FLOAT) {
nasm_error(ERR_NONFATAL, "expecting floating-point number");
return NULL;
}
if (!float_const(tokval->t_charptr, sign, result, formats[type].bytes))
return NULL;
i = scan(scpriv, tokval);
if (i != ')') {
nasm_error(ERR_NONFATAL, "expecting `)'");
return NULL;
}
p = result+formats[type].start+formats[type].len;
val = 0;
for (j = formats[type].len; j; j--) {
p--;
val = (val << 8) + *p;
}
begintemp();
addtotemp(EXPR_SIMPLE, val);
i = scan(scpriv, tokval);
return finishtemp();
}
static expr *eval_strfunc(enum strfunc type)
{
char *string;
size_t string_len;
int64_t val;
bool parens, rn_warn;
parens = false;
i = scan(scpriv, tokval);
if (i == '(') {
parens = true;
i = scan(scpriv, tokval);
}
if (i != TOKEN_STR) {
nasm_error(ERR_NONFATAL, "expecting string");
return NULL;
}
string_len = string_transform(tokval->t_charptr, tokval->t_inttwo,
&string, type);
if (string_len == (size_t)-1) {
nasm_error(ERR_NONFATAL, "invalid string for transform");
return NULL;
}
val = readstrnum(string, string_len, &rn_warn);
if (parens) {
i = scan(scpriv, tokval);
if (i != ')') {
nasm_error(ERR_NONFATAL, "expecting `)'");
return NULL;
}
}
if (rn_warn)
nasm_error(ERR_WARNING|ERR_PASS1, "character constant too long");
begintemp();
addtotemp(EXPR_SIMPLE, val);
i = scan(scpriv, tokval);
return finishtemp();
}
static int64_t eval_ifunc(int64_t val, enum ifunc func)
{
int errtype;
uint64_t uval = (uint64_t)val;
int64_t rv;
switch (func) {
case IFUNC_ILOG2E:
case IFUNC_ILOG2W:
errtype = (func == IFUNC_ILOG2E) ? ERR_NONFATAL : ERR_WARNING;
if (!is_power2(uval))
nasm_error(errtype, "ilog2 argument is not a power of two");
/* fall through */
case IFUNC_ILOG2F:
rv = ilog2_64(uval);
break;
case IFUNC_ILOG2C:
rv = (uval < 2) ? 0 : ilog2_64(uval-1) + 1;
break;
default:
nasm_error(ERR_PANIC, "invalid IFUNC token %d", func);
rv = 0;
break;
}
return rv;
}
static expr *expr6(int critical)
{
int32_t type;
expr *e;
int32_t label_seg;
int64_t label_ofs;
int64_t tmpval;
bool rn_warn;
char *scope;
switch (i) {
case '-':
i = scan(scpriv, tokval);
e = expr6(critical);
if (!e)
return NULL;
return scalar_mult(e, -1L, false);
case '+':
i = scan(scpriv, tokval);
return expr6(critical);
case '~':
i = scan(scpriv, tokval);
e = expr6(critical);
if (!e)
return NULL;
if (is_just_unknown(e))
return unknown_expr();
else if (!is_simple(e)) {
nasm_error(ERR_NONFATAL, "`~' operator may only be applied to"
" scalar values");
return NULL;
}
return scalarvect(~reloc_value(e));
case '!':
i = scan(scpriv, tokval);
e = expr6(critical);
if (!e)
return NULL;
if (is_just_unknown(e))
return unknown_expr();
else if (!is_simple(e)) {
nasm_error(ERR_NONFATAL, "`!' operator may only be applied to"
" scalar values");
return NULL;
}
return scalarvect(!reloc_value(e));
case TOKEN_IFUNC:
{
enum ifunc func = tokval->t_integer;
i = scan(scpriv, tokval);
e = expr6(critical);
if (!e)
return NULL;
if (is_just_unknown(e))
return unknown_expr();
else if (!is_simple(e)) {
nasm_error(ERR_NONFATAL, "function may only be applied to"
" scalar values");
return NULL;
}
return scalarvect(eval_ifunc(reloc_value(e), func));
}
case TOKEN_SEG:
i = scan(scpriv, tokval);
e = expr6(critical);
if (!e)
return NULL;
e = segment_part(e);
if (!e)
return NULL;
if (is_unknown(e) && critical) {
nasm_error(ERR_NONFATAL, "unable to determine segment base");
return NULL;
}
return e;
case TOKEN_FLOATIZE:
return eval_floatize(tokval->t_integer);
case TOKEN_STRFUNC:
return eval_strfunc(tokval->t_integer);
case '(':
i = scan(scpriv, tokval);
e = bexpr(critical);
if (!e)
return NULL;
if (i != ')') {
nasm_error(ERR_NONFATAL, "expecting `)'");
return NULL;
}
i = scan(scpriv, tokval);
return e;
case TOKEN_NUM:
case TOKEN_STR:
case TOKEN_REG:
case TOKEN_ID:
case TOKEN_INSN: /* Opcodes that occur here are really labels */
case TOKEN_HERE:
case TOKEN_BASE:
case TOKEN_DECORATOR:
begintemp();
switch (i) {
case TOKEN_NUM:
addtotemp(EXPR_SIMPLE, tokval->t_integer);
break;
case TOKEN_STR:
tmpval = readstrnum(tokval->t_charptr, tokval->t_inttwo, &rn_warn);
if (rn_warn)
nasm_error(ERR_WARNING|ERR_PASS1, "character constant too long");
addtotemp(EXPR_SIMPLE, tmpval);
break;
case TOKEN_REG:
addtotemp(tokval->t_integer, 1L);
if (hint && hint->type == EAH_NOHINT)
hint->base = tokval->t_integer, hint->type = EAH_MAKEBASE;
break;
case TOKEN_ID:
case TOKEN_INSN:
case TOKEN_HERE:
case TOKEN_BASE:
/*
* If !location.known, this indicates that no
* symbol, Here or Base references are valid because we
* are in preprocess-only mode.
*/
if (!location.known) {
nasm_error(ERR_NONFATAL,
"%s not supported in preprocess-only mode",
(i == TOKEN_HERE ? "`$'" :
i == TOKEN_BASE ? "`$$'" :
"symbol references"));
addtotemp(EXPR_UNKNOWN, 1L);
break;
}
type = EXPR_SIMPLE; /* might get overridden by UNKNOWN */
if (i == TOKEN_BASE) {
label_seg = in_abs_seg ? abs_seg : location.segment;
label_ofs = 0;
} else if (i == TOKEN_HERE) {
label_seg = in_abs_seg ? abs_seg : location.segment;
label_ofs = in_abs_seg ? abs_offset : location.offset;
} else {
if (!lookup_label(tokval->t_charptr, &label_seg, &label_ofs)) {
scope = local_scope(tokval->t_charptr);
if (critical == 2) {
nasm_error(ERR_NONFATAL, "symbol `%s%s' undefined",
scope,tokval->t_charptr);
return NULL;
} else if (critical == 1) {
nasm_error(ERR_NONFATAL,
"symbol `%s%s' not defined before use",
scope,tokval->t_charptr);
return NULL;
} else {
if (opflags)
*opflags |= OPFLAG_FORWARD;
type = EXPR_UNKNOWN;
label_seg = NO_SEG;
label_ofs = 1;
}
}
if (opflags && is_extern(tokval->t_charptr))
*opflags |= OPFLAG_EXTERN;
}
addtotemp(type, label_ofs);
if (label_seg != NO_SEG)
addtotemp(EXPR_SEGBASE + label_seg, 1L);
break;
case TOKEN_DECORATOR:
addtotemp(EXPR_RDSAE, tokval->t_integer);
break;
}
i = scan(scpriv, tokval);
return finishtemp();
default:
nasm_error(ERR_NONFATAL, "expression syntax error");
return NULL;
}
}
expr *evaluate(scanner sc, void *scprivate, struct tokenval *tv,
int *fwref, int critical, struct eval_hints *hints)
{
expr *e;
expr *f = NULL;
hint = hints;
if (hint)
hint->type = EAH_NOHINT;
if (critical & CRITICAL) {
critical &= ~CRITICAL;
bexpr = rexp0;
} else
bexpr = expr0;
scan = sc;
scpriv = scprivate;
tokval = tv;
opflags = fwref;
if (tokval->t_type == TOKEN_INVALID)
i = scan(scpriv, tokval);
else
i = tokval->t_type;
while (ntempexprs) /* initialize temporary storage */
nasm_free(tempexprs[--ntempexprs]);
e = bexpr(critical);
if (!e)
return NULL;
if (i == TOKEN_WRT) {
i = scan(scpriv, tokval); /* eat the WRT */
f = expr6(critical);
if (!f)
return NULL;
}
e = scalar_mult(e, 1L, false); /* strip far-absolute segment part */
if (f) {
expr *g;
if (is_just_unknown(f))
g = unknown_expr();
else {
int64_t value;
begintemp();
if (!is_reloc(f)) {
nasm_error(ERR_NONFATAL, "invalid right-hand operand to WRT");
return NULL;
}
value = reloc_seg(f);
if (value == NO_SEG)
value = reloc_value(f) | SEG_ABS;
else if (!(value & SEG_ABS) && !(value % 2) && critical) {
nasm_error(ERR_NONFATAL, "invalid right-hand operand to WRT");
return NULL;
}
addtotemp(EXPR_WRT, value);
g = finishtemp();
}
e = add_vectors(e, g);
}
return e;
}
Reference in New Issue View Git Blame Copy Permalink