static void
elf_x86_amd64_write_secthead_rel(unsigned char *bufp,
elf_secthead *shead,
elf_section_index symtab_idx,
elf_section_index sindex)
{
yasm_intnum *nreloc;
yasm_intnum *relocsize;
YASM_WRITE_32_L(bufp, shead->rel_name ? shead->rel_name->index : 0);
YASM_WRITE_32_L(bufp, SHT_RELA);
YASM_WRITE_64Z_L(bufp, 0);
YASM_WRITE_64Z_L(bufp, 0);
YASM_WRITE_64Z_L(bufp, shead->rel_offset);
nreloc = yasm_intnum_create_uint(shead->nreloc);
relocsize = yasm_intnum_create_uint(RELOC64A_SIZE);
yasm_intnum_calc(relocsize, YASM_EXPR_MUL, nreloc);
YASM_WRITE_64I_L(bufp, relocsize); /* size */
yasm_intnum_destroy(nreloc);
yasm_intnum_destroy(relocsize);
YASM_WRITE_32_L(bufp, symtab_idx); /* link: symtab index */
YASM_WRITE_32_L(bufp, shead->index); /* info: relocated's index */
YASM_WRITE_64Z_L(bufp, RELOC64_ALIGN); /* align */
YASM_WRITE_64Z_L(bufp, RELOC64A_SIZE); /* entity size */
}
static int
run_output_test(Test_Entry *test)
{
char *valstr = yasm__xstrdup(test->input);
yasm_intnum *intn = yasm_intnum_create_hex(valstr);
unsigned long size, i;
unsigned char out[100];
int bad;
yasm_xfree(valstr);
if (test->negate)
yasm_intnum_calc(intn, YASM_EXPR_NEG, NULL);
size = yasm_intnum_size_leb128(intn, test->sign);
if (size != test->outsize) {
yasm_intnum_destroy(intn);
sprintf(failmsg, "%ssigned %s%s size() bad size: expected %lu, got %lu!",
test->sign?"":"un", test->negate?"-":"", test->input,
test->outsize, size);
return 1;
}
for (i=0; i<sizeof(out); i++)
out[i] = 0xFF;
size = yasm_intnum_get_leb128(intn, out, test->sign);
if (size != test->outsize) {
yasm_intnum_destroy(intn);
sprintf(failmsg, "%ssigned %s%s get() bad size: expected %lu, got %lu!",
test->sign?"":"un", test->negate?"-":"", test->input,
test->outsize, size);
return 1;
}
bad = 0;
for (i=0; i<test->outsize && !bad; i++) {
if (out[i] != test->result[i])
bad = 1;
}
if (bad) {
yasm_intnum_destroy(intn);
sprintf(failmsg, "%ssigned %s%s get() bad output!",
test->sign?"":"un", test->negate?"-":"", test->input);
return 1;
}
yasm_intnum_destroy(intn);
return 0;
}
void
elf_reloc_entry_destroy(void *entry)
{
if (((elf_reloc_entry*)entry)->addend)
yasm_intnum_destroy(((elf_reloc_entry*)entry)->addend);
yasm_xfree(entry);
}
/* takes ownership of addr */
elf_reloc_entry *
elf_reloc_entry_create(yasm_symrec *sym,
yasm_symrec *wrt,
yasm_intnum *addr,
int rel,
size_t valsize)
{
elf_reloc_entry *entry;
if (!elf_march->accepts_reloc)
yasm_internal_error(N_("Unsupported machine for ELF output"));
if (!elf_march->accepts_reloc(valsize, wrt, elf_ssyms))
{
if (addr)
yasm_intnum_destroy(addr);
return NULL;
}
if (sym == NULL)
yasm_internal_error("sym is null");
entry = yasm_xmalloc(sizeof(elf_reloc_entry));
entry->reloc.sym = sym;
entry->reloc.addr = addr;
entry->rtype_rel = rel;
entry->valsize = valsize;
entry->addend = NULL;
entry->wrt = wrt;
return entry;
}
static void
elf_x86_x86_handle_reloc_addend(yasm_intnum *intn,
elf_reloc_entry *reloc,
unsigned long offset)
{
if (!reloc->wrt && reloc->is_GOT_sym && reloc->valsize == 32 && offset != 0)
{
yasm_intnum *off_intn = yasm_intnum_create_uint(offset);
yasm_intnum_calc(intn, YASM_EXPR_ADD, off_intn);
yasm_intnum_destroy(off_intn);
}
return; /* .rel: Leave addend in intn */
}
int
yasm_dir_helper_intn(void *obj, yasm_valparam *vp, unsigned long line,
void *data, uintptr_t arg)
{
yasm_object *object = (yasm_object *)obj;
/*@only@*/ /*@null@*/ yasm_expr *e;
/*@dependent@*/ /*@null@*/ yasm_intnum *local;
yasm_intnum **intn = (yasm_intnum **)data;
if (*intn)
yasm_intnum_destroy(*intn);
if (!(e = yasm_vp_expr(vp, object->symtab, line)) ||
!(local = yasm_expr_get_intnum(&e, 0))) {
yasm_error_set(YASM_ERROR_NOT_CONSTANT,
N_("argument to `%s' is not an integer"),
vp->val);
if (e)
yasm_expr_destroy(e);
return -1;
}
*intn = yasm_intnum_copy(local);
yasm_expr_destroy(e);
return 0;
}
static int
run_input_test(Test_Entry *test)
{
char *valstr = yasm__xstrdup(test->input);
yasm_intnum *intn = yasm_intnum_create_hex(valstr);
yasm_intnum *testn;
unsigned long size;
yasm_xfree(valstr);
if (test->negate)
yasm_intnum_calc(intn, YASM_EXPR_NEG, NULL);
testn = yasm_intnum_create_leb128(test->result, test->sign, &size);
if (size != test->outsize) {
yasm_intnum_destroy(testn);
yasm_intnum_destroy(intn);
sprintf(failmsg, "%ssigned %s%s create() bad size: expected %lu, got %lu!",
test->sign?"":"un", test->negate?"-":"", test->input,
test->outsize, size);
return 1;
}
yasm_intnum_calc(intn, YASM_EXPR_EQ, testn);
if (!yasm_intnum_is_pos1(intn)) {
yasm_intnum_destroy(testn);
yasm_intnum_destroy(intn);
sprintf(failmsg, "%ssigned %s%s create() bad output!",
test->sign?"":"un", test->negate?"-":"", test->input);
return 1;
}
yasm_intnum_destroy(testn);
yasm_intnum_destroy(intn);
return 0;
}
int
yasm_value_output_basic(yasm_value *value, /*@out@*/ unsigned char *buf,
size_t destsize, yasm_bytecode *bc, int warn,
yasm_arch *arch)
{
/*@dependent@*/ /*@null@*/ yasm_intnum *intn = NULL;
/*@only@*/ yasm_intnum *outval;
int sym_local;
int retval = 1;
unsigned int valsize = value->size;
if (value->no_warn)
warn = 0;
if (value->abs) {
/* Handle floating point expressions */
if (!value->rel && value->abs->op == YASM_EXPR_IDENT
&& value->abs->terms[0].type == YASM_EXPR_FLOAT) {
if (yasm_arch_floatnum_tobytes(arch, value->abs->terms[0].data.flt,
buf, destsize, valsize, 0, warn))
return -1;
else
return 1;
}
/* Check for complex float expressions */
if (yasm_expr__contains(value->abs, YASM_EXPR_FLOAT)) {
yasm_error_set(YASM_ERROR_FLOATING_POINT,
N_("floating point expression too complex"));
return -1;
}
/* Handle normal integer expressions */
intn = yasm_expr_get_intnum(&value->abs, 1);
if (!intn) {
/* Second try before erroring: yasm_expr_get_intnum doesn't handle
* SEG:OFF, so try simplifying out any to just the OFF portion,
* then getting the intnum again.
*/
yasm_expr *seg = yasm_expr_extract_deep_segoff(&value->abs);
if (seg)
yasm_expr_destroy(seg);
intn = yasm_expr_get_intnum(&value->abs, 1);
}
if (!intn) {
/* Still don't have an integer! */
yasm_error_set(YASM_ERROR_TOO_COMPLEX,
N_("expression too complex"));
return -1;
}
}
/* Adjust warn for signed/unsigned integer warnings */
if (warn != 0)
warn = value->sign ? -1 : 1;
if (value->rel) {
/* If relative portion is not in bc section, don't try to handle it
* here. Otherwise get the relative portion's offset.
*/
/*@dependent@*/ yasm_bytecode *rel_prevbc;
unsigned long dist;
sym_local = yasm_symrec_get_label(value->rel, &rel_prevbc);
if (value->wrt || value->seg_of || value->section_rel || !sym_local)
return 0; /* we can't handle SEG, WRT, or external symbols */
if (rel_prevbc->section != bc->section)
return 0; /* not in this section */
if (!value->curpos_rel)
return 0; /* not PC-relative */
/* Calculate value relative to current assembly position */
dist = yasm_bc_next_offset(rel_prevbc);
if (dist < bc->offset) {
outval = yasm_intnum_create_uint(bc->offset - dist);
yasm_intnum_calc(outval, YASM_EXPR_NEG, NULL);
} else {
dist -= bc->offset;
outval = yasm_intnum_create_uint(dist);
}
if (value->rshift > 0) {
/*@only@*/ yasm_intnum *shamt =
yasm_intnum_create_uint((unsigned long)value->rshift);
yasm_intnum_calc(outval, YASM_EXPR_SHR, shamt);
yasm_intnum_destroy(shamt);
}
/* Add in absolute portion */
if (intn)
yasm_intnum_calc(outval, YASM_EXPR_ADD, intn);
/* Output! */
if (yasm_arch_intnum_tobytes(arch, outval, buf, destsize, valsize, 0,
bc, warn))
retval = -1;
yasm_intnum_destroy(outval);
return retval;
}
if (value->seg_of || value->rshift || value->curpos_rel || value->ip_rel
|| value->section_rel)
return 0; /* We can't handle this with just an absolute */
if (intn) {
/* Output just absolute portion */
if (yasm_arch_intnum_tobytes(arch, intn, buf, destsize, valsize, 0, bc,
warn))
retval = -1;
} else {
/* No absolute or relative portions: output 0 */
outval = yasm_intnum_create_uint(0);
if (yasm_arch_intnum_tobytes(arch, outval, buf, destsize, valsize, 0,
bc, warn))
retval = -1;
yasm_intnum_destroy(outval);
}
return retval;
}
yasm_intnum *
yasm_value_get_intnum(yasm_value *value, yasm_bytecode *bc, int calc_bc_dist)
{
/*@dependent@*/ /*@null@*/ yasm_intnum *intn = NULL;
/*@only@*/ yasm_intnum *outval;
int sym_local;
if (value->abs) {
/* Handle integer expressions, if non-integer or too complex, return
* NULL.
*/
intn = yasm_expr_get_intnum(&value->abs, calc_bc_dist);
if (!intn)
return NULL;
}
if (value->rel) {
/* If relative portion is not in bc section, return NULL.
* Otherwise get the relative portion's offset.
*/
/*@dependent@*/ yasm_bytecode *rel_prevbc;
unsigned long dist;
if (!bc)
return NULL; /* Can't calculate relative value */
sym_local = yasm_symrec_get_label(value->rel, &rel_prevbc);
if (value->wrt || value->seg_of || value->section_rel || !sym_local)
return NULL; /* we can't handle SEG, WRT, or external symbols */
if (rel_prevbc->section != bc->section)
return NULL; /* not in this section */
if (!value->curpos_rel)
return NULL; /* not PC-relative */
/* Calculate value relative to current assembly position */
dist = yasm_bc_next_offset(rel_prevbc);
if (dist < bc->offset) {
outval = yasm_intnum_create_uint(bc->offset - dist);
yasm_intnum_calc(outval, YASM_EXPR_NEG, NULL);
} else {
dist -= bc->offset;
outval = yasm_intnum_create_uint(dist);
}
if (value->rshift > 0) {
/*@only@*/ yasm_intnum *shamt =
yasm_intnum_create_uint((unsigned long)value->rshift);
yasm_intnum_calc(outval, YASM_EXPR_SHR, shamt);
yasm_intnum_destroy(shamt);
}
/* Add in absolute portion */
if (intn)
yasm_intnum_calc(outval, YASM_EXPR_ADD, intn);
return outval;
}
if (intn)
return yasm_intnum_copy(intn);
/* No absolute or relative portions: output 0 */
return yasm_intnum_create_uint(0);
}
int
yasm_value_finalize(yasm_value *value, yasm_bytecode *precbc)
{
if (!value->abs)
return 0;
value->abs = yasm_expr__level_tree(value->abs, 1, 1, 0, 0, NULL, NULL);
/* quit early if there was an issue in simplify() */
if (yasm_error_occurred())
return 1;
/* Strip top-level AND masking to an all-1s mask the same size
* of the value size. This allows forced avoidance of overflow warnings.
*/
if (value->abs->op == YASM_EXPR_AND) {
int term;
/* Calculate 1<<size - 1 value */
yasm_intnum *mask = yasm_intnum_create_uint(1);
yasm_intnum *mask_tmp = yasm_intnum_create_uint(value->size);
yasm_intnum_calc(mask, YASM_EXPR_SHL, mask_tmp);
yasm_intnum_set_uint(mask_tmp, 1);
yasm_intnum_calc(mask, YASM_EXPR_SUB, mask_tmp);
yasm_intnum_destroy(mask_tmp);
/* Walk terms and delete matching masks */
for (term=value->abs->numterms-1; term>=0; term--) {
if (value->abs->terms[term].type == YASM_EXPR_INT &&
yasm_intnum_compare(value->abs->terms[term].data.intn,
mask) == 0) {
/* Delete the intnum */
yasm_intnum_destroy(value->abs->terms[term].data.intn);
/* Slide everything to its right over by 1 */
if (term != value->abs->numterms-1) /* if it wasn't last.. */
memmove(&value->abs->terms[term],
&value->abs->terms[term+1],
(value->abs->numterms-1-term)*
sizeof(yasm_expr__item));
/* Update numterms */
value->abs->numterms--;
/* Indicate warnings have been disabled */
value->no_warn = 1;
}
}
if (value->abs->numterms == 1)
value->abs->op = YASM_EXPR_IDENT;
yasm_intnum_destroy(mask);
}
/* Handle trivial (IDENT) cases immediately */
if (value->abs->op == YASM_EXPR_IDENT) {
switch (value->abs->terms[0].type) {
case YASM_EXPR_INT:
if (yasm_intnum_is_zero(value->abs->terms[0].data.intn)) {
yasm_expr_destroy(value->abs);
value->abs = NULL;
}
return 0;
case YASM_EXPR_REG:
case YASM_EXPR_FLOAT:
return 0;
case YASM_EXPR_SYM:
value->rel = value->abs->terms[0].data.sym;
yasm_expr_destroy(value->abs);
value->abs = NULL;
return 0;
case YASM_EXPR_EXPR:
/* Bring up lower values. */
while (value->abs->op == YASM_EXPR_IDENT
&& value->abs->terms[0].type == YASM_EXPR_EXPR) {
yasm_expr *sube = value->abs->terms[0].data.expn;
yasm_xfree(value->abs);
value->abs = sube;
}
break;
default:
yasm_internal_error(N_("unexpected expr term type"));
}
}
if (value_finalize_scan(value, value->abs, precbc, 0))
return 1;
value->abs = yasm_expr__level_tree(value->abs, 1, 1, 0, 0, NULL, NULL);
/* Simplify 0 in abs to NULL */
if (value->abs->op == YASM_EXPR_IDENT
&& value->abs->terms[0].type == YASM_EXPR_INT
&& yasm_intnum_is_zero(value->abs->terms[0].data.intn)) {
yasm_expr_destroy(value->abs);
value->abs = NULL;
}
return 0;
}
static int
xdf_objfmt_output_value(yasm_value *value, unsigned char *buf,
unsigned int destsize, unsigned long offset,
yasm_bytecode *bc, int warn, /*@null@*/ void *d)
{
/*@null@*/ xdf_objfmt_output_info *info = (xdf_objfmt_output_info *)d;
yasm_objfmt_xdf *objfmt_xdf;
/*@dependent@*/ /*@null@*/ yasm_intnum *intn;
unsigned long intn_minus;
int retval;
unsigned int valsize = value->size;
assert(info != NULL);
objfmt_xdf = info->objfmt_xdf;
if (value->abs)
value->abs = yasm_expr_simplify(value->abs, 1);
/* Try to output constant and PC-relative section-local first.
* Note this does NOT output any value with a SEG, WRT, external,
* cross-section, or non-PC-relative reference (those are handled below).
*/
switch (yasm_value_output_basic(value, buf, destsize, bc, warn,
info->object->arch)) {
case -1:
return 1;
case 0:
break;
default:
return 0;
}
if (value->section_rel) {
yasm_error_set(YASM_ERROR_TOO_COMPLEX,
N_("xdf: relocation too complex"));
return 1;
}
intn_minus = 0;
if (value->rel) {
xdf_reloc *reloc;
reloc = yasm_xmalloc(sizeof(xdf_reloc));
reloc->reloc.addr = yasm_intnum_create_uint(bc->offset + offset);
reloc->reloc.sym = value->rel;
reloc->base = NULL;
reloc->size = valsize/8;
reloc->shift = value->rshift;
if (value->seg_of)
reloc->type = XDF_RELOC_SEG;
else if (value->wrt) {
reloc->base = value->wrt;
reloc->type = XDF_RELOC_WRT;
} else if (value->curpos_rel) {
reloc->type = XDF_RELOC_RIP;
/* Adjust to start of section, so subtract out the bytecode
* offset.
*/
intn_minus = bc->offset;
} else
reloc->type = XDF_RELOC_REL;
info->xsd->nreloc++;
yasm_section_add_reloc(info->sect, (yasm_reloc *)reloc, yasm_xfree);
}
if (intn_minus > 0) {
intn = yasm_intnum_create_uint(intn_minus);
yasm_intnum_calc(intn, YASM_EXPR_NEG, NULL);
} else
intn = yasm_intnum_create_uint(0);
if (value->abs) {
yasm_intnum *intn2 = yasm_expr_get_intnum(&value->abs, 0);
if (!intn2) {
yasm_error_set(YASM_ERROR_TOO_COMPLEX,
N_("xdf: relocation too complex"));
yasm_intnum_destroy(intn);
return 1;
}
yasm_intnum_calc(intn, YASM_EXPR_ADD, intn2);
}
retval = yasm_arch_intnum_tobytes(info->object->arch, intn, buf, destsize,
valsize, 0, bc, warn);
yasm_intnum_destroy(intn);
return retval;
}
/*@-mustfree@*/
static /*@only@*/ yasm_expr *
expr_level_op(/*@returned@*/ /*@only@*/ yasm_expr *e, int fold_const,
int simplify_ident, int simplify_reg_mul)
{
int i, j, o, fold_numterms, level_numterms, level_fold_numterms;
int first_int_term = -1;
/* Determine how many operands will need to be brought up (for leveling).
* Go ahead and bring up any IDENT'ed values.
*/
while (e->op == YASM_EXPR_IDENT && e->terms[0].type == YASM_EXPR_EXPR) {
yasm_expr *sube = e->terms[0].data.expn;
yasm_xfree(e);
e = sube;
}
/* If non-numeric expression, don't fold constants. */
if (e->op > YASM_EXPR_NONNUM)
fold_const = 0;
level_numterms = e->numterms;
level_fold_numterms = 0;
for (i=0; i<e->numterms; i++) {
/* Search downward until we find something *other* than an
* IDENT, then bring it up to the current level.
*/
while (e->terms[i].type == YASM_EXPR_EXPR &&
e->terms[i].data.expn->op == YASM_EXPR_IDENT) {
yasm_expr *sube = e->terms[i].data.expn;
e->terms[i] = sube->terms[0];
yasm_xfree(sube);
}
if (e->terms[i].type == YASM_EXPR_EXPR &&
e->terms[i].data.expn->op == e->op) {
/* It's an expression w/the same operator, add in its numterms.
* But don't forget to subtract one for the expr itself!
*/
level_numterms += e->terms[i].data.expn->numterms - 1;
/* If we're folding constants, count up the number of constants
* that will be merged in.
*/
if (fold_const)
for (j=0; j<e->terms[i].data.expn->numterms; j++)
if (e->terms[i].data.expn->terms[j].type ==
YASM_EXPR_INT)
level_fold_numterms++;
}
/* Find the first integer term (if one is present) if we're folding
* constants.
*/
if (fold_const && first_int_term == -1 &&
e->terms[i].type == YASM_EXPR_INT)
first_int_term = i;
}
/* Look for other integer terms if there's one and combine.
* Also eliminate empty spaces when combining and adjust numterms
* variables.
*/
fold_numterms = e->numterms;
if (first_int_term != -1) {
for (i=first_int_term+1, o=first_int_term+1; i<e->numterms; i++) {
if (e->terms[i].type == YASM_EXPR_INT) {
yasm_intnum_calc(e->terms[first_int_term].data.intn, e->op,
e->terms[i].data.intn);
fold_numterms--;
level_numterms--;
/* make sure to delete folded intnum */
yasm_intnum_destroy(e->terms[i].data.intn);
} else if (o != i) {
/* copy term if it changed places */
e->terms[o++] = e->terms[i];
} else
o++;
}
if (simplify_ident) {
int new_fold_numterms;
/* Simplify identities and make IDENT if possible. */
new_fold_numterms =
expr_simplify_identity(e, fold_numterms, &first_int_term,
simplify_reg_mul);
level_numterms -= fold_numterms-new_fold_numterms;
fold_numterms = new_fold_numterms;
}
if (fold_numterms == 1)
e->op = YASM_EXPR_IDENT;
}
/* Only level operators that allow more than two operand terms.
* Also don't bother leveling if it's not necessary to bring up any terms.
*/
if ((e->op != YASM_EXPR_ADD && e->op != YASM_EXPR_MUL &&
e->op != YASM_EXPR_OR && e->op != YASM_EXPR_AND &&
e->op != YASM_EXPR_LOR && e->op != YASM_EXPR_LAND &&
e->op != YASM_EXPR_LXOR && e->op != YASM_EXPR_XOR) ||
level_numterms <= fold_numterms) {
/* Downsize e if necessary */
if (fold_numterms < e->numterms && e->numterms > 2)
e = yasm_xrealloc(e, sizeof(yasm_expr)+((fold_numterms<2) ? 0 :
sizeof(yasm_expr__item)*(fold_numterms-2)));
/* Update numterms */
e->numterms = fold_numterms;
return e;
}
/* Adjust numterms for constant folding from terms being "pulled up".
* Careful: if there's no integer term in e, then save space for it.
*/
if (fold_const) {
level_numterms -= level_fold_numterms;
if (first_int_term == -1 && level_fold_numterms != 0)
level_numterms++;
}
/* Alloc more (or conceivably less, but not usually) space for e */
e = yasm_xrealloc(e, sizeof(yasm_expr)+((level_numterms<2) ? 0 :
sizeof(yasm_expr__item)*(level_numterms-2)));
/* Copy up ExprItem's. Iterate from right to left to keep the same
* ordering as was present originally.
* Combine integer terms as necessary.
*/
for (i=fold_numterms-1, o=level_numterms-1; i>=0; i--) {
if (e->terms[i].type == YASM_EXPR_EXPR &&
e->terms[i].data.expn->op == e->op) {
/* bring up subexpression */
yasm_expr *sube = e->terms[i].data.expn;
/* copy terms right to left */
for (j=sube->numterms-1; j>=0; j--) {
if (fold_const && sube->terms[j].type == YASM_EXPR_INT) {
/* Need to fold it in.. but if there's no int term already,
* just copy into a new one.
*/
if (first_int_term == -1) {
first_int_term = o--;
e->terms[first_int_term] = sube->terms[j]; /* struc */
} else {
yasm_intnum_calc(e->terms[first_int_term].data.intn,
e->op, sube->terms[j].data.intn);
/* make sure to delete folded intnum */
yasm_intnum_destroy(sube->terms[j].data.intn);
}
} else {
if (o == first_int_term)
o--;
e->terms[o--] = sube->terms[j]; /* structure copy */
}
}
/* delete subexpression, but *don't delete nodes* (as we've just
* copied them!)
*/
yasm_xfree(sube);
} else if (o != i) {
/* copy operand if it changed places */
if (o == first_int_term)
o--;
e->terms[o] = e->terms[i];
/* If we moved the first_int_term, change first_int_num too */
if (i == first_int_term)
first_int_term = o;
o--;
} else
o--;
}
/* Simplify identities, make IDENT if possible, and save to e->numterms. */
if (simplify_ident && first_int_term != -1) {
e->numterms = expr_simplify_identity(e, level_numterms,
&first_int_term, simplify_reg_mul);
} else {
e->numterms = level_numterms;
if (level_numterms == 1)
e->op = YASM_EXPR_IDENT;
}
return e;
}
/* Check for and simplify identities. Returns new number of expr terms.
* Sets e->op = EXPR_IDENT if numterms ends up being 1.
* Uses numterms parameter instead of e->numterms for basis of "new" number
* of terms.
* Assumes int_term is *only* integer term in e.
* NOTE: Really designed to only be used by expr_level_op().
*/
static int
expr_simplify_identity(yasm_expr *e, int numterms, int *int_term,
int simplify_reg_mul)
{
int i;
int save_numterms;
/* Don't do this step if it's 1*REG. Save and restore numterms so
* yasm_expr__contains() works correctly.
*/
save_numterms = e->numterms;
e->numterms = numterms;
if (simplify_reg_mul || e->op != YASM_EXPR_MUL
|| !yasm_intnum_is_pos1(e->terms[*int_term].data.intn)
|| !yasm_expr__contains(e, YASM_EXPR_REG)) {
/* Check for simple identities that delete the intnum.
* Don't delete if the intnum is the only thing in the expn.
*/
if ((*int_term == 0 && numterms > 1 &&
expr_can_destroy_int_left(e->op, e->terms[0].data.intn)) ||
(*int_term > 0 &&
expr_can_destroy_int_right(e->op,
e->terms[*int_term].data.intn))) {
/* Delete the intnum */
yasm_intnum_destroy(e->terms[*int_term].data.intn);
/* Slide everything to its right over by 1 */
if (*int_term != numterms-1) /* if it wasn't last.. */
memmove(&e->terms[*int_term], &e->terms[*int_term+1],
(numterms-1-*int_term)*sizeof(yasm_expr__item));
/* Update numterms */
numterms--;
*int_term = -1; /* no longer an int term */
}
}
e->numterms = save_numterms;
/* Check for simple identites that delete everything BUT the intnum.
* Don't bother if the intnum is the only thing in the expn.
*/
if (numterms > 1 && *int_term != -1 &&
expr_is_constant(e->op, e->terms[*int_term].data.intn)) {
/* Loop through, deleting everything but the integer term */
for (i=0; i<e->numterms; i++)
if (i != *int_term)
expr_delete_term(&e->terms[i], 1);
/* Move integer term to the first term (if not already there) */
if (*int_term != 0)
e->terms[0] = e->terms[*int_term]; /* structure copy */
/* Set numterms to 1 */
numterms = 1;
}
/* Compute NOT, NEG, and LNOT on single intnum. */
if (numterms == 1 && *int_term == 0 &&
(e->op == YASM_EXPR_NOT || e->op == YASM_EXPR_NEG ||
e->op == YASM_EXPR_LNOT))
yasm_intnum_calc(e->terms[0].data.intn, e->op, NULL);
/* Change expression to IDENT if possible. */
if (numterms == 1)
e->op = YASM_EXPR_IDENT;
/* Return the updated numterms */
return numterms;
}