*
* Data structures:
* - Interval tree to store spans and associated data
- * - Queue Q
+ * - Queues QA and QB
*
* Each span keeps track of:
* - Associated bytecode (bytecode that depends on the span length)
* - Negative/Positive thresholds
* - Span ID (unique within each bytecode)
*
- * How org and align are handled:
+ * How org and align and any other offset-based bytecodes are handled:
+ *
* Some portions are critical values that must not depend on any bytecode
* offset (either relative or absolute).
*
- * ALIGN/ORG/other offset-based bytecodes: Length set to bump offset to
- * alignment. Span from 0 to bytecode, update on any change. Can
- * update to new offset for things like align, which gets propagated
- * to update dependent spans. Alignment/ORG value is critical value.
- * Cannot be combined with TIMES.
+ * Length set to bump offset to required position. Span created from first
+ * bytecode in section to bytecode, update when it exceeds the next offset.
+ * This threshold can update to new offset for things like align, which gets
+ * propagated to update dependent spans.
+ *
+ * Offset-based bytecodes are updated by QA before any expansion of normal
+ * bytecodes (in QB). This is done because offset-based bytecodes can absorb
+ * expansions.
+ *
+ * Alignment/ORG value is critical value.
+ * Cannot be combined with TIMES.
*
* How times is handled:
*
/* Special handling: see descriptions above */
enum {
NOT_SPECIAL = 0,
- SPECIAL_BC_OFFSET,
- SPECIAL_TIMES
+ SPECIAL_BC_OFFSET
} special;
long cur_val;
long len_diff; /* used only for optimize_term_expand */
} optimize_data;
-static void
-optimize_add_span(void *add_span_data, yasm_bytecode *bc, int id,
- const yasm_value *value, long neg_thres, long pos_thres)
+static yasm_span *
+create_span(yasm_bytecode *bc, int id, /*@null@*/ const yasm_value *value,
+ int special, long neg_thres, long pos_thres)
{
- optimize_data *optd = (optimize_data *)add_span_data;
yasm_span *span = yasm_xmalloc(sizeof(yasm_span));
span->bc = bc;
- yasm_value_init_copy(&span->depval, value);
+ if (value)
+ yasm_value_init_copy(&span->depval, value);
+ else
+ yasm_value_initialize(&span->depval, NULL, 0);
span->rel_term = NULL;
span->terms = NULL;
span->items = NULL;
span->num_terms = 0;
- span->special = NOT_SPECIAL;
+ span->special = special;
span->cur_val = 0;
span->new_val = 0;
span->neg_thres = neg_thres;
span->id = id;
span->active = 1;
+ return span;
+}
+
+static void
+optimize_add_span(void *add_span_data, yasm_bytecode *bc, int id,
+ const yasm_value *value, long neg_thres, long pos_thres)
+{
+ optimize_data *optd = (optimize_data *)add_span_data;
+ yasm_span *span;
+ span = create_span(bc, id, value, NOT_SPECIAL, neg_thres, pos_thres);
TAILQ_INSERT_TAIL(&optd->spans, span, link);
}
/* Create items with dummy value */
span->items[i].type = YASM_EXPR_INT;
span->items[i].data.intn = yasm_intnum_create_int(0);
+
+ /* Check for circular references */
+ if ((span->bc->bc_index >= span->terms[i].precbc->bc_index &&
+ span->bc->bc_index <= span->terms[i].precbc2->bc_index) ||
+ (span->bc->bc_index >= span->terms[i].precbc2->bc_index &&
+ span->bc->bc_index <= span->terms[i].precbc->bc_index))
+ yasm_error_set(YASM_ERROR_VALUE,
+ N_("circular reference detected"));
}
}
}
}
/* Recalculate span value based on current span replacement values.
- * Returns 1 if span exceeded thresholds.
+ * Returns 1 if span needs expansion (e.g. exceeded thresholds).
*/
static int
recalc_normal_span(yasm_span *span)
if (span->new_val == LONG_MAX)
span->active = 0;
+ /* If id=0, flag update on any change */
+ if (span->id == 0)
+ return (span->new_val != span->cur_val);
+
return (span->new_val < span->neg_thres
|| span->new_val > span->pos_thres);
}
/* Recalculate/adjust len of offset-based bytecodes here */
long neg_thres = 0;
long pos_thres = bc->offset+bc->len;
- int retval = yasm_bc_expand(bc, 0, 0,
+ int retval = yasm_bc_expand(bc, 1, 0,
(long)(prevbc->offset+prevbc->len),
&neg_thres, &pos_thres);
yasm_errwarn_propagate(errwarns, bc->line);
if (!recalc_normal_span(span))
return; /* didn't exceed thresholds, we're done */
- /* Exceeded thresholds, probably need to add to Q for expansion */
+ /* Exceeded thresholds, need to add to Q for expansion */
switch (span->special) {
case NOT_SPECIAL:
STAILQ_INSERT_TAIL(&optd->QB, span, linkq);
- span->active = 2; /* Mark as being in Q */
break;
case SPECIAL_BC_OFFSET:
STAILQ_INSERT_TAIL(&optd->QA, span, linkq);
- span->active = 2; /* Mark as being in Q */
- break;
- case SPECIAL_TIMES:
break;
}
+ span->active = 2; /* Mark as being in Q */
}
void
saw_error = 1;
else {
if (bc->callback->special == YASM_BC_SPECIAL_OFFSET) {
- span = yasm_xmalloc(sizeof(yasm_span));
-
- span->bc = bc;
- yasm_value_initialize(&span->depval, NULL, 0);
- span->rel_term = NULL;
- span->terms = NULL;
- span->items = NULL;
- span->num_terms = 0;
- span->special = SPECIAL_BC_OFFSET;
- span->cur_val = (long)bc->offset;
- span->new_val = 0;
- span->neg_thres = 0;
- span->pos_thres = (long)(bc->offset+bc->len);
- span->id = 0;
- span->active = 1;
-
+ span = create_span(bc, 1, NULL, SPECIAL_BC_OFFSET, 0,
+ (long)(bc->offset+bc->len));
TAILQ_INSERT_TAIL(&optd.spans, span, link);
if (bc->multiple) {
yasm_error_set(YASM_ERROR_VALUE,
saw_error = 1;
}
}
- /* TODO: times */
-#if 0
- if (bc->len != 0 && bc->multiple) {
- yasm_internal_error("multiple not yet supported");
- }
-#endif
+
offset += bc->len;
}
switch (span->special) {
case NOT_SPECIAL:
span_create_terms(span);
- if (recalc_normal_span(span)) {
+ if (yasm_error_occurred()) {
+ yasm_errwarn_propagate(errwarns, span->bc->line);
+ saw_error = 1;
+ } else if (recalc_normal_span(span)) {
retval = yasm_bc_expand(span->bc, span->id, span->cur_val,
span->new_val, &span->neg_thres,
&span->pos_thres);
span->rel_term->cur_val = 0;
span->rel_term->new_val = (long)span->bc->offset;
break;
- case SPECIAL_TIMES:
- break;
}
}
span->rel_term->cur_val = span->rel_term->new_val;
span->cur_val = span->new_val;
break;
- case SPECIAL_TIMES:
- break;
}
}
projects / yasm / commitdiff