/* dwarf2dbg.c - DWARF2 debug support
- Copyright (C) 1999-2017 Free Software Foundation, Inc.
+ Copyright (C) 1999-2019 Free Software Foundation, Inc.
Contributed by David Mosberger-Tang <davidm@hpl.hp.com>
This file is part of GAS, the GNU Assembler.
#define DWARF2_ARANGES_VERSION 2
#endif
-/* This implementation output version 2 .debug_line information. */
+/* This implementation outputs version 3 .debug_line information. */
#ifndef DWARF2_LINE_VERSION
-#define DWARF2_LINE_VERSION 2
+#define DWARF2_LINE_VERSION 3
#endif
#include "subsegs.h"
#define TC_PARSE_CONS_RETURN_NONE BFD_RELOC_NONE
#endif
-struct line_entry {
+struct line_entry
+{
struct line_entry *next;
symbolS *label;
struct dwarf2_line_info loc;
};
-struct line_subseg {
+/* Don't change the offset of next in line_entry. set_or_check_view
+ calls in dwarf2_gen_line_info_1 depend on it. */
+static char unused[offsetof(struct line_entry, next) ? -1 : 1]
+ATTRIBUTE_UNUSED;
+
+struct line_subseg
+{
struct line_subseg *next;
subsegT subseg;
struct line_entry *head;
struct line_entry **pmove_tail;
};
-struct line_seg {
+struct line_seg
+{
struct line_seg *next;
segT seg;
struct line_subseg *head;
static struct line_seg *all_segs;
static struct line_seg **last_seg_ptr;
-struct file_entry {
+struct file_entry
+{
const char *filename;
unsigned int dir;
};
bfd_boolean dwarf2_loc_mark_labels;
/* Current location as indicated by the most recent .loc directive. */
-static struct dwarf2_line_info current = {
+static struct dwarf2_line_info current =
+{
1, 1, 0, 0,
DWARF2_LINE_DEFAULT_IS_STMT ? DWARF2_FLAG_IS_STMT : 0,
- 0
+ 0, NULL
};
+/* This symbol is used to recognize view number forced resets in loc
+ lists. */
+static symbolS *force_reset_view;
+
+/* This symbol evaluates to an expression that, if nonzero, indicates
+ some view assert check failed. */
+static symbolS *view_assert_failed;
+
/* The size of an address on the target. */
static unsigned int sizeof_address;
\f
{
expressionS exp;
+ memset (&exp, 0, sizeof exp);
exp.X_op = O_symbol;
exp.X_add_symbol = symbol;
exp.X_add_number = 0;
return lss;
}
+/* (Un)reverse the line_entry list starting from H. */
+
+static struct line_entry *
+reverse_line_entry_list (struct line_entry *h)
+{
+ struct line_entry *p = NULL, *e, *n;
+
+ for (e = h; e; e = n)
+ {
+ n = e->next;
+ e->next = p;
+ p = e;
+ }
+ return p;
+}
+
+/* Compute the view for E based on the previous entry P. If we
+ introduce an (undefined) view symbol for P, and H is given (P must
+ be the tail in this case), introduce view symbols for earlier list
+ entries as well, until one of them is constant. */
+
+static void
+set_or_check_view (struct line_entry *e, struct line_entry *p,
+ struct line_entry *h)
+{
+ expressionS viewx;
+
+ memset (&viewx, 0, sizeof (viewx));
+ viewx.X_unsigned = 1;
+
+ /* First, compute !(E->label > P->label), to tell whether or not
+ we're to reset the view number. If we can't resolve it to a
+ constant, keep it symbolic. */
+ if (!p || (e->loc.view == force_reset_view && force_reset_view))
+ {
+ viewx.X_op = O_constant;
+ viewx.X_add_number = 0;
+ viewx.X_add_symbol = NULL;
+ viewx.X_op_symbol = NULL;
+ }
+ else
+ {
+ viewx.X_op = O_gt;
+ viewx.X_add_number = 0;
+ viewx.X_add_symbol = e->label;
+ viewx.X_op_symbol = p->label;
+ resolve_expression (&viewx);
+ if (viewx.X_op == O_constant)
+ viewx.X_add_number = !viewx.X_add_number;
+ else
+ {
+ viewx.X_add_symbol = make_expr_symbol (&viewx);
+ viewx.X_add_number = 0;
+ viewx.X_op_symbol = NULL;
+ viewx.X_op = O_logical_not;
+ }
+ }
+
+ if (S_IS_DEFINED (e->loc.view) && symbol_constant_p (e->loc.view))
+ {
+ expressionS *value = symbol_get_value_expression (e->loc.view);
+ /* We can't compare the view numbers at this point, because in
+ VIEWX we've only determined whether we're to reset it so
+ far. */
+ if (viewx.X_op == O_constant)
+ {
+ if (!value->X_add_number != !viewx.X_add_number)
+ as_bad (_("view number mismatch"));
+ }
+ /* Record the expression to check it later. It is the result of
+ a logical not, thus 0 or 1. We just add up all such deferred
+ expressions, and resolve it at the end. */
+ else if (!value->X_add_number)
+ {
+ symbolS *deferred = make_expr_symbol (&viewx);
+ if (view_assert_failed)
+ {
+ expressionS chk;
+
+ memset (&chk, 0, sizeof (chk));
+ chk.X_unsigned = 1;
+ chk.X_op = O_add;
+ chk.X_add_number = 0;
+ chk.X_add_symbol = view_assert_failed;
+ chk.X_op_symbol = deferred;
+ deferred = make_expr_symbol (&chk);
+ }
+ view_assert_failed = deferred;
+ }
+ }
+
+ if (viewx.X_op != O_constant || viewx.X_add_number)
+ {
+ expressionS incv;
+
+ if (!p->loc.view)
+ {
+ p->loc.view = symbol_temp_make ();
+ gas_assert (!S_IS_DEFINED (p->loc.view));
+ }
+
+ memset (&incv, 0, sizeof (incv));
+ incv.X_unsigned = 1;
+ incv.X_op = O_symbol;
+ incv.X_add_symbol = p->loc.view;
+ incv.X_add_number = 1;
+
+ if (viewx.X_op == O_constant)
+ {
+ gas_assert (viewx.X_add_number == 1);
+ viewx = incv;
+ }
+ else
+ {
+ viewx.X_add_symbol = make_expr_symbol (&viewx);
+ viewx.X_add_number = 0;
+ viewx.X_op_symbol = make_expr_symbol (&incv);
+ viewx.X_op = O_multiply;
+ }
+ }
+
+ if (!S_IS_DEFINED (e->loc.view))
+ {
+ symbol_set_value_expression (e->loc.view, &viewx);
+ S_SET_SEGMENT (e->loc.view, expr_section);
+ symbol_set_frag (e->loc.view, &zero_address_frag);
+ }
+
+ /* Define and attempt to simplify any earlier views needed to
+ compute E's. */
+ if (h && p && p->loc.view && !S_IS_DEFINED (p->loc.view))
+ {
+ struct line_entry *h2;
+ /* Reverse the list to avoid quadratic behavior going backwards
+ in a single-linked list. */
+ struct line_entry *r = reverse_line_entry_list (h);
+
+ gas_assert (r == p);
+ /* Set or check views until we find a defined or absent view. */
+ do
+ set_or_check_view (r, r->next, NULL);
+ while (r->next && r->next->loc.view && !S_IS_DEFINED (r->next->loc.view)
+ && (r = r->next));
+
+ /* Unreverse the list, so that we can go forward again. */
+ h2 = reverse_line_entry_list (p);
+ gas_assert (h2 == h);
+
+ /* Starting from the last view we just defined, attempt to
+ simplify the view expressions, until we do so to P. */
+ do
+ {
+ gas_assert (S_IS_DEFINED (r->loc.view));
+ resolve_expression (symbol_get_value_expression (r->loc.view));
+ }
+ while (r != p && (r = r->next));
+
+ /* Now that we've defined and computed all earlier views that might
+ be needed to compute E's, attempt to simplify it. */
+ resolve_expression (symbol_get_value_expression (e->loc.view));
+ }
+}
+
/* Record an entry for LOC occurring at LABEL. */
static void
e->loc = *loc;
lss = get_line_subseg (now_seg, now_subseg, TRUE);
+
+ if (loc->view)
+ set_or_check_view (e,
+ !lss->head ? NULL : (struct line_entry *)lss->ptail,
+ lss->head);
+
*lss->ptail = e;
lss->ptail = &e->next;
}
{
if (debug_type == DEBUG_DWARF2)
{
- const char *filename = as_where (&line->line);
+ const char *filename;
+
+ memset (line, 0, sizeof (*line));
+ filename = as_where (&line->line);
line->filenum = get_filenum (filename, 0);
line->column = 0;
line->flags = DWARF2_FLAG_IS_STMT;
line->isa = current.isa;
line->discriminator = current.discriminator;
+ line->view = NULL;
}
else
*line = current;
{
struct dwarf2_line_info loc;
- if (!dwarf2_loc_directive_seen && debug_type != DEBUG_DWARF2)
+ if (debug_type != DEBUG_DWARF2
+ ? !dwarf2_loc_directive_seen
+ : !seen_at_least_1_file ())
return;
dwarf2_where (&loc);
| DWARF2_FLAG_PROLOGUE_END
| DWARF2_FLAG_EPILOGUE_BEGIN);
current.discriminator = 0;
+ current.view = NULL;
}
/* Called for each (preferably code) label. If dwarf2_loc_mark_labels
- Pass .file "source.c" to s_app_file
- Handle .file 1 "source.c" by adding an entry to the DWARF-2 file table
- If an entry is added to the file table, return a pointer to the filename. */
+ If an entry is added to the file table, return a pointer to the filename. */
char *
-dwarf2_directive_file (int dummy ATTRIBUTE_UNUSED)
+dwarf2_directive_filename (void)
{
offsetT num;
char *filename;
return filename;
}
+/* Calls dwarf2_directive_filename, but discards its result.
+ Used in pseudo-op tables where the function result is ignored. */
+
+void
+dwarf2_directive_file (int dummy ATTRIBUTE_UNUSED)
+{
+ (void) dwarf2_directive_filename ();
+}
+
void
dwarf2_directive_loc (int dummy ATTRIBUTE_UNUSED)
{
return;
}
}
+ else if (strcmp (p, "view") == 0)
+ {
+ symbolS *sym;
+
+ (void) restore_line_pointer (c);
+ SKIP_WHITESPACE ();
+
+ if (ISDIGIT (*input_line_pointer)
+ || *input_line_pointer == '-')
+ {
+ bfd_boolean force_reset = *input_line_pointer == '-';
+
+ value = get_absolute_expression ();
+ if (value != 0)
+ {
+ as_bad (_("numeric view can only be asserted to zero"));
+ return;
+ }
+ if (force_reset && force_reset_view)
+ sym = force_reset_view;
+ else
+ {
+ sym = symbol_temp_new (absolute_section, value,
+ &zero_address_frag);
+ if (force_reset)
+ force_reset_view = sym;
+ }
+ }
+ else
+ {
+ char *name = read_symbol_name ();
+
+ if (!name)
+ return;
+ sym = symbol_find_or_make (name);
+ if (S_IS_DEFINED (sym) || symbol_equated_p (sym))
+ {
+ if (S_IS_VOLATILE (sym))
+ sym = symbol_clone (sym, 1);
+ else if (!S_CAN_BE_REDEFINED (sym))
+ {
+ as_bad (_("symbol `%s' is already defined"), name);
+ return;
+ }
+ }
+ S_SET_SEGMENT (sym, undefined_section);
+ S_SET_VALUE (sym, 0);
+ symbol_set_frag (sym, &zero_address_frag);
+ }
+ current.view = sym;
+ }
else
{
as_bad (_("unknown .loc sub-directive `%s'"), p);
demand_empty_rest_of_line ();
dwarf2_loc_directive_seen = TRUE;
debug_type = DEBUG_NONE;
+
+ /* If we were given a view id, emit the row right away. */
+ if (current.view)
+ dwarf2_emit_insn (0);
}
void
{
expressionS exp;
+ memset (&exp, 0, sizeof exp);
out_opcode (DW_LNS_extended_op);
out_uleb128 (sizeof_address + 1);
symbolS *to_sym;
expressionS exp;
+ memset (&exp, 0, sizeof exp);
gas_assert (pexp->X_op == O_subtract);
to_sym = pexp->X_add_symbol;
expressionS exp;
int max_chars;
+ memset (&exp, 0, sizeof exp);
exp.X_op = O_subtract;
exp.X_add_symbol = to_sym;
exp.X_op_symbol = from_sym;
frag = symbol_get_frag (lab);
frag_ofs = S_GET_VALUE (lab);
- if (last_frag == NULL)
+ if (last_frag == NULL
+ || (e->loc.view == force_reset_view && force_reset_view
+ /* If we're going to reset the view, but we know we're
+ advancing the PC, we don't have to force with
+ set_address. We know we do when we're at the same
+ address of the same frag, and we know we might when
+ we're in the beginning of a frag, and we were at the
+ end of the previous frag. */
+ && (frag == last_frag
+ ? (last_frag_ofs == frag_ofs)
+ : (frag_ofs == 0
+ && ((offsetT)last_frag_ofs
+ >= get_frag_fix (last_frag, seg))))))
{
out_set_addr (lab);
out_inc_line_addr (line_delta, 0);
struct line_seg *s;
int sizeof_offset;
+ memset (&exp, 0, sizeof exp);
sizeof_offset = out_header (line_seg, &exp);
line_end = exp.X_add_symbol;
expressionS exp;
unsigned int i;
+ memset (&exp, 0, sizeof exp);
subseg_set (ranges_seg, 0);
/* Base Address Entry. */
char *p;
int sizeof_offset;
+ memset (&exp, 0, sizeof exp);
sizeof_offset = out_header (aranges_seg, &exp);
aranges_end = exp.X_add_symbol;
size = -exp.X_add_number;
else
out_abbrev (DW_AT_ranges, DW_FORM_data8);
}
- out_abbrev (DW_AT_name, DW_FORM_string);
- out_abbrev (DW_AT_comp_dir, DW_FORM_string);
- out_abbrev (DW_AT_producer, DW_FORM_string);
+ out_abbrev (DW_AT_name, DW_FORM_strp);
+ out_abbrev (DW_AT_comp_dir, DW_FORM_strp);
+ out_abbrev (DW_AT_producer, DW_FORM_strp);
out_abbrev (DW_AT_language, DW_FORM_data2);
out_abbrev (0, 0);
/* Emit a description of this compilation unit for .debug_info. */
static void
-out_debug_info (segT info_seg, segT abbrev_seg, segT line_seg, segT ranges_seg)
+out_debug_info (segT info_seg, segT abbrev_seg, segT line_seg, segT ranges_seg,
+ symbolS *name_sym, symbolS *comp_dir_sym, symbolS *producer_sym)
{
- char producer[128];
- const char *comp_dir;
- const char *dirname;
expressionS exp;
symbolS *info_end;
- char *p;
- int len;
int sizeof_offset;
+ memset (&exp, 0, sizeof exp);
sizeof_offset = out_header (info_seg, &exp);
info_end = exp.X_add_symbol;
TC_DWARF2_EMIT_OFFSET (section_symbol (ranges_seg), sizeof_offset);
}
+ /* DW_AT_name, DW_AT_comp_dir and DW_AT_producer. Symbols in .debug_str
+ setup in out_debug_str below. */
+ TC_DWARF2_EMIT_OFFSET (name_sym, sizeof_offset);
+ TC_DWARF2_EMIT_OFFSET (comp_dir_sym, sizeof_offset);
+ TC_DWARF2_EMIT_OFFSET (producer_sym, sizeof_offset);
+
+ /* DW_AT_language. Yes, this is probably not really MIPS, but the
+ dwarf2 draft has no standard code for assembler. */
+ out_two (DW_LANG_Mips_Assembler);
+
+ symbol_set_value_now (info_end);
+}
+
+/* Emit the three debug strings needed in .debug_str and setup symbols
+ to them for use in out_debug_info. */
+static void
+out_debug_str (segT str_seg, symbolS **name_sym, symbolS **comp_dir_sym,
+ symbolS **producer_sym)
+{
+ char producer[128];
+ const char *comp_dir;
+ const char *dirname;
+ char *p;
+ int len;
+
+ subseg_set (str_seg, 0);
+
/* DW_AT_name. We don't have the actual file name that was present
on the command line, so assume files[1] is the main input file.
We're not supposed to get called unless at least one line number
entry was emitted, so this should always be defined. */
+ *name_sym = symbol_temp_new_now ();
if (files_in_use == 0)
abort ();
if (files[1].dir)
memcpy (p, files[1].filename, len);
/* DW_AT_comp_dir */
+ *comp_dir_sym = symbol_temp_new_now ();
comp_dir = remap_debug_filename (getpwd ());
len = strlen (comp_dir) + 1;
p = frag_more (len);
memcpy (p, comp_dir, len);
/* DW_AT_producer */
+ *producer_sym = symbol_temp_new_now ();
sprintf (producer, "GNU AS %s", VERSION);
len = strlen (producer) + 1;
p = frag_more (len);
memcpy (p, producer, len);
-
- /* DW_AT_language. Yes, this is probably not really MIPS, but the
- dwarf2 draft has no standard code for assembler. */
- out_two (DW_LANG_Mips_Assembler);
-
- symbol_set_value_now (info_end);
}
void
out_debug_line (line_seg);
/* If this is assembler generated line info, and there is no
- debug_info already, we need .debug_info and .debug_abbrev
- sections as well. */
+ debug_info already, we need .debug_info, .debug_abbrev and
+ .debug_str sections as well. */
if (emit_other_sections)
{
segT abbrev_seg;
segT aranges_seg;
segT ranges_seg;
+ segT str_seg;
+ symbolS *name_sym, *comp_dir_sym, *producer_sym;
gas_assert (all_segs);
info_seg = subseg_new (".debug_info", 0);
abbrev_seg = subseg_new (".debug_abbrev", 0);
aranges_seg = subseg_new (".debug_aranges", 0);
+ str_seg = subseg_new (".debug_str", 0);
bfd_set_section_flags (stdoutput, info_seg,
SEC_READONLY | SEC_DEBUGGING);
SEC_READONLY | SEC_DEBUGGING);
bfd_set_section_flags (stdoutput, aranges_seg,
SEC_READONLY | SEC_DEBUGGING);
+ bfd_set_section_flags (stdoutput, str_seg,
+ (SEC_READONLY | SEC_DEBUGGING
+ | SEC_MERGE | SEC_STRINGS));
+ str_seg->entsize = 1;
record_alignment (aranges_seg, ffs (2 * sizeof_address) - 1);
out_debug_aranges (aranges_seg, info_seg);
out_debug_abbrev (abbrev_seg, info_seg, line_seg);
- out_debug_info (info_seg, abbrev_seg, line_seg, ranges_seg);
+ out_debug_str (str_seg, &name_sym, &comp_dir_sym, &producer_sym);
+ out_debug_info (info_seg, abbrev_seg, line_seg, ranges_seg,
+ name_sym, comp_dir_sym, producer_sym);
+ }
+}
+
+/* Perform any deferred checks pertaining to debug information. */
+
+void
+dwarf2dbg_final_check (void)
+{
+ /* Perform reset-view checks. Don't evaluate view_assert_failed
+ recursively: it could be very deep. It's a chain of adds, with
+ each chain element pointing to the next in X_add_symbol, and
+ holding the check value in X_op_symbol. */
+ while (view_assert_failed)
+ {
+ expressionS *exp;
+ symbolS *sym;
+ offsetT failed;
+
+ gas_assert (!symbol_resolved_p (view_assert_failed));
+
+ exp = symbol_get_value_expression (view_assert_failed);
+ sym = view_assert_failed;
+
+ /* If view_assert_failed looks like a compound check in the
+ chain, break it up. */
+ if (exp->X_op == O_add && exp->X_add_number == 0 && exp->X_unsigned)
+ {
+ view_assert_failed = exp->X_add_symbol;
+ sym = exp->X_op_symbol;
+ }
+ else
+ view_assert_failed = NULL;
+
+ failed = resolve_symbol_value (sym);
+ if (!symbol_resolved_p (sym) || failed)
+ {
+ as_bad (_("view number mismatch"));
+ break;
+ }
}
}