Bug 567106 - Could we have a fix to solve the "0" line issue as the GDB
diff --git a/agent/tcf/services/runctrl.c b/agent/tcf/services/runctrl.c
index f27f0be..a7c9f4b 100644
--- a/agent/tcf/services/runctrl.c
+++ b/agent/tcf/services/runctrl.c
@@ -1540,13 +1540,13 @@
return 0;
}
-#if EN_STEP_OVER
-
static void get_machine_code_area(CodeArea * area, void * args) {
*(CodeArea **)args = (CodeArea *)tmp_alloc(sizeof(CodeArea));
memcpy(*(CodeArea **)args, area, sizeof(CodeArea));
}
+#if EN_STEP_OVER
+
static int is_within_function_epilogue(Context * ctx, ContextAddress ip) {
Symbol * sym = NULL;
int sym_class = SYM_CLASS_UNKNOWN;
@@ -1975,7 +1975,6 @@
}
}
else if (addr < ext->step_range_start || addr >= ext->step_range_end) {
- int same_line = 0;
int function_prologue = 0;
CodeArea * area = ext->step_code_area;
if (area == NULL) {
@@ -2019,39 +2018,50 @@
return 0;
}
- same_line = is_same_line(ext->step_code_area, area);
- if (!same_line) {
- function_prologue = is_function_prologue(ctx, addr, ext->step_code_area);
- if (cache_miss_count() > 0) {
- free_code_area(ext->step_code_area);
- ext->step_code_area = area;
- errno = ERR_CACHE_MISS;
- return -1;
+ if (ext->step_code_area->start_line == 0) {
+ /* Clang associates some instructions in the middle of functions to line 0.
+ * That is valid DWARF, we need to step over such no-line-info instructions.
+ */
+ ext->step_range_start = ext->step_code_area->start_address;
+ ext->step_range_end = ext->step_code_area->end_address;
+ free_code_area(ext->step_code_area);
+ ext->step_code_area = area;
+ }
+ else {
+ int same_line = is_same_line(ext->step_code_area, area);
+ if (!same_line) {
+ function_prologue = is_function_prologue(ctx, addr, ext->step_code_area);
+ if (cache_miss_count() > 0) {
+ free_code_area(ext->step_code_area);
+ ext->step_code_area = area;
+ errno = ERR_CACHE_MISS;
+ return -1;
+ }
}
- }
- free_code_area(area);
+ free_code_area(area);
- /* We are doing reverse step-over/into line. The first line has already been skipped, we are now trying to reach
- * the beginning of previous line. If we are still on same line but have reached the beginning of the line, then we
- * are done.
- */
- if (same_line && do_reverse && ext->step_line_cnt > 0 && addr == ext->step_code_area->start_address) {
- ext->step_done = REASON_STEP;
- return 0;
- }
- if (!same_line && !function_prologue) {
- if (!do_reverse ||
- (ext->step_line_cnt == 0 && addr == ext->step_code_area->start_address) ||
- ext->step_line_cnt >= 2) {
+ /* We are doing reverse step-over/into line. The first line has already been skipped, we are now trying to reach
+ * the beginning of previous line. If we are still on same line but have reached the beginning of the line, then we
+ * are done.
+ */
+ if (same_line && do_reverse && ext->step_line_cnt > 0 && addr == ext->step_code_area->start_address) {
ext->step_done = REASON_STEP;
return 0;
}
- /* Current IP is in the middle of a source line.
- * Continue stepping to get to the beginning of the line */
- ext->step_line_cnt++;
+ if (!same_line && !function_prologue) {
+ if (!do_reverse ||
+ (ext->step_line_cnt == 0 && addr == ext->step_code_area->start_address) ||
+ ext->step_line_cnt >= 2) {
+ ext->step_done = REASON_STEP;
+ return 0;
+ }
+ /* Current IP is in the middle of a source line.
+ * Continue stepping to get to the beginning of the line */
+ ext->step_line_cnt++;
+ }
+ ext->step_range_start = ext->step_code_area->start_address;
+ ext->step_range_end = ext->step_code_area->end_address;
}
- ext->step_range_start = ext->step_code_area->start_address;
- ext->step_range_end = ext->step_code_area->end_address;
/* When doing reverse step-into/over line, if we have already skipped the first line, we want to reach
* the beginning of current line, fix step range to handle this.
@@ -2069,7 +2079,7 @@
return 0;
}
if (address_to_line(ctx, addr, addr + 1, get_machine_code_area, &area) < 0) return -1;
- if (area == NULL || !is_function_prologue(ctx, addr, area)) {
+ if (area == NULL || (area->start_line != 0 && !is_function_prologue(ctx, addr, area))) {
if (cache_miss_count() > 0) {
errno = ERR_CACHE_MISS;
return -1;
@@ -2083,6 +2093,29 @@
#endif /* EN_STEP_LINE */
case RM_STEP_OUT:
case RM_REVERSE_STEP_OUT:
+#if EN_STEP_LINE
+ {
+ /* Clang associates some instructions in the middle of functions to line 0.
+ * That is valid DWARF, we need to step over such no-line-info instructions.
+ */
+ CodeArea * area = NULL;
+ if (address_to_line(ctx, addr, addr + 1, get_machine_code_area, &area) < 0) return -1;
+ if (area != NULL && area->start_line == 0) {
+ ext->step_range_start = area->start_address;
+ ext->step_range_end = area->end_address;
+ switch (ext->step_mode) {
+ case RM_STEP_OUT:
+ if (context_can_resume(ctx, ext->step_continue_mode = RM_STEP_INTO_RANGE)) return 0;
+ if (context_can_resume(ctx, ext->step_continue_mode = RM_STEP_INTO)) return 0;
+ break;
+ case RM_REVERSE_STEP_OUT:
+ if (context_can_resume(ctx, ext->step_continue_mode = RM_REVERSE_STEP_INTO_RANGE)) return 0;
+ if (context_can_resume(ctx, ext->step_continue_mode = RM_REVERSE_STEP_INTO)) return 0;
+ break;
+ }
+ }
+ }
+#endif /* EN_STEP_LINE */
ext->step_done = REASON_STEP;
return 0;
default:
