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[V2 09/23] vla: changed string length semantic.
- From: Keven Boell <keven dot boell at intel dot com>
- To: gdb-patches at sourceware dot org
- Cc: keven dot boell at intel dot com, sanimir dot agovic at intel dot com
- Date: Fri, 11 Jul 2014 11:21:21 +0200
- Subject: [V2 09/23] vla: changed string length semantic.
- Authentication-results: sourceware.org; auth=none
- References: <1405070495-6948-1-git-send-email-keven dot boell at intel dot com>
This patch changes the semantic of the Dwarf string length
attribute to reflect the standard. This serves as pre-work
to get variable strings in Fortran to work.
2014-05-28 Keven Boell <keven.boell@intel.com>
Sanimir Agovic <sanimir.agovic@intel.com>
* dwarf2read.c (read_tag_string_type): changed
semantic of DW_AT_string_length to be able to
handle Dwarf blocks as well. Support for
DW_AT_byte_length added to get correct length
if specified in combination with
DW_AT_string_length.
(attr_to_dynamic_prop): added
functionality to add Dwarf operators to baton
data attribute. Added post values to baton
as required by the string evaluation case.
(read_subrange_type): Adapt caller.
(set_die_type): Adapt caller.
(add_post_values_to_baton): New function.
* dwarf2loc.c (dwarf2_evaluate_property): Evaluate
post processing dwarf.
* dwarf2loc.h (struct dwarf2_property_baton): Add
post dwarf values attribute.
Change-Id: I6edfa005f416cddc8e364d34891b9abf6b44f757
Signed-off-by: Keven Boell <keven.boell@intel.com>
---
gdb/dwarf2read.c | 144 +++++++++++++++++++++++++++++++++++++++++++++++-------
1 file changed, 126 insertions(+), 18 deletions(-)
diff --git a/gdb/dwarf2read.c b/gdb/dwarf2read.c
index f612cd8..9b755b2 100644
--- a/gdb/dwarf2read.c
+++ b/gdb/dwarf2read.c
@@ -1847,6 +1847,12 @@ static void free_dwo_file_cleanup (void *);
static void process_cu_includes (void);
static void check_producer (struct dwarf2_cu *cu);
+
+static int
+attr_to_dynamic_prop (const struct attribute *attr, struct die_info *die,
+ struct dwarf2_cu *cu, struct dynamic_prop *prop,
+ const gdb_byte *additional_data, int additional_data_size);
+
/* Various complaints about symbol reading that don't abort the process. */
@@ -14201,29 +14207,94 @@ read_tag_string_type (struct die_info *die, struct dwarf2_cu *cu)
struct gdbarch *gdbarch = get_objfile_arch (objfile);
struct type *type, *range_type, *index_type, *char_type;
struct attribute *attr;
- unsigned int length;
+ unsigned int length = UINT_MAX;
+ index_type = objfile_type (objfile)->builtin_int;
+ range_type = create_static_range_type (NULL, index_type, 1, length);
+
+ /* If DW_AT_string_length is defined, the length is stored at some location
+ * in memory. */
attr = dwarf2_attr (die, DW_AT_string_length, cu);
if (attr)
{
- length = DW_UNSND (attr);
+ if (attr_form_is_block (attr))
+ {
+ struct attribute *byte_size, *bit_size;
+ struct dynamic_prop high;
+
+ byte_size = dwarf2_attr (die, DW_AT_byte_size, cu);
+ bit_size = dwarf2_attr (die, DW_AT_bit_size, cu);
+
+ /* DW_AT_byte_size should never occur together in combination with
+ DW_AT_string_length. */
+ if ((byte_size == NULL && bit_size != NULL) ||
+ (byte_size != NULL && bit_size == NULL))
+ complaint (&symfile_complaints, _("DW_AT_byte_size AND "
+ "DW_AT_bit_size found together at the same time."));
+
+ /* If DW_AT_string_length AND DW_AT_byte_size exist together, it
+ describes the number of bytes that should be read from the length
+ memory location. */
+ if (byte_size != NULL && bit_size == NULL)
+ {
+ /* Build new dwarf2_locexpr_baton structure with additions to the
+ data attribute, to reflect DWARF specialities to get address
+ sizes. */
+ const gdb_byte append_ops[] = {
+ /* DW_OP_deref_size: size of an address on the target machine
+ (bytes), where the size will be specified by the next
+ operand. */
+ DW_OP_deref_size,
+ /* Operand for DW_OP_deref_size. */
+ DW_UNSND (byte_size) };
+
+ if (!attr_to_dynamic_prop (attr, die, cu, &high,
+ append_ops, ARRAY_SIZE (append_ops)))
+ complaint (&symfile_complaints,
+ _("Could not parse DW_AT_byte_size"));
+ }
+ else if (bit_size != NULL && byte_size == NULL)
+ complaint (&symfile_complaints, _("DW_AT_string_length AND "
+ "DW_AT_bit_size found but not supported yet."));
+ /* If DW_AT_string_length WITHOUT DW_AT_byte_size exist, the default
+ is the address size of the target machine. */
+ else
+ {
+ const gdb_byte append_ops[] = { DW_OP_deref };
+
+ if (!attr_to_dynamic_prop (attr, die, cu, &high, append_ops,
+ ARRAY_SIZE (append_ops)))
+ complaint (&symfile_complaints,
+ _("Could not parse DW_AT_string_length"));
+ }
+
+ TYPE_RANGE_DATA (range_type)->high = high;
+ }
+ else
+ {
+ TYPE_HIGH_BOUND (range_type) = DW_UNSND (attr);
+ TYPE_HIGH_BOUND_KIND (range_type) = PROP_CONST;
+ }
}
else
{
- /* Check for the DW_AT_byte_size attribute. */
+ /* Check for the DW_AT_byte_size attribute, which represents the length
+ in this case. */
attr = dwarf2_attr (die, DW_AT_byte_size, cu);
if (attr)
{
- length = DW_UNSND (attr);
+ TYPE_HIGH_BOUND (range_type) = DW_UNSND (attr);
+ TYPE_HIGH_BOUND_KIND (range_type) = PROP_CONST;
}
else
{
- length = 1;
+ TYPE_HIGH_BOUND (range_type) = 1;
+ TYPE_HIGH_BOUND_KIND (range_type) = PROP_CONST;
}
}
- index_type = objfile_type (objfile)->builtin_int;
- range_type = create_static_range_type (NULL, index_type, 1, length);
char_type = language_string_char_type (cu->language_defn, gdbarch);
type = create_string_type (NULL, char_type, range_type);
@@ -14540,13 +14611,15 @@ read_base_type (struct die_info *die, struct dwarf2_cu *cu)
return set_die_type (die, type, cu);
}
+
/* Parse dwarf attribute if it's a block, reference or constant and put the
resulting value of the attribute into struct bound_prop.
Returns 1 if ATTR could be resolved into PROP, 0 otherwise. */
static int
attr_to_dynamic_prop (const struct attribute *attr, struct die_info *die,
- struct dwarf2_cu *cu, struct dynamic_prop *prop)
+ struct dwarf2_cu *cu, struct dynamic_prop *prop,
+ const gdb_byte *additional_data, int additional_data_size)
{
struct dwarf2_property_baton *baton;
struct obstack *obstack = &cu->objfile->objfile_obstack;
@@ -14559,8 +14632,25 @@ attr_to_dynamic_prop (const struct attribute *attr, struct die_info *die,
baton = obstack_alloc (obstack, sizeof (*baton));
baton->referenced_type = NULL;
baton->locexpr.per_cu = cu->per_cu;
- baton->locexpr.size = DW_BLOCK (attr)->size;
- baton->locexpr.data = DW_BLOCK (attr)->data;
+
+ if (additional_data != NULL && additional_data_size > 0)
+ {
+ gdb_byte *data;
+
+ data = obstack_alloc (&cu->objfile->objfile_obstack,
+ DW_BLOCK (attr)->size + additional_data_size);
+ memcpy (data, DW_BLOCK (attr)->data, DW_BLOCK (attr)->size);
+ memcpy (data + DW_BLOCK (attr)->size,
+ additional_data, additional_data_size);
+
+ baton->locexpr.data = data;
+ baton->locexpr.size = DW_BLOCK (attr)->size + additional_data_size;
+ }
+ else
+ {
+ baton->locexpr.data = DW_BLOCK (attr)->data;
+ baton->locexpr.size = DW_BLOCK (attr)->size;
+ }
prop->data.baton = baton;
prop->kind = PROP_LOCEXPR;
gdb_assert (prop->data.baton != NULL);
@@ -14590,8 +14680,26 @@ attr_to_dynamic_prop (const struct attribute *attr, struct die_info *die,
baton = obstack_alloc (obstack, sizeof (*baton));
baton->referenced_type = die_type (target_die, target_cu);
baton->locexpr.per_cu = cu->per_cu;
- baton->locexpr.size = DW_BLOCK (target_attr)->size;
- baton->locexpr.data = DW_BLOCK (target_attr)->data;
+
+ if (additional_data != NULL && additional_data_size > 0)
+ {
+ gdb_byte *data;
+
+ data = obstack_alloc (&cu->objfile->objfile_obstack,
+ DW_BLOCK (attr)->size + additional_data_size);
+ memcpy (data, DW_BLOCK (attr)->data, DW_BLOCK (attr)->size);
+ memcpy (data + DW_BLOCK (attr)->size,
+ additional_data, additional_data_size);
+
+ baton->locexpr.data = data;
+ baton->locexpr.size = DW_BLOCK (attr)->size + additional_data_size;
+ }
+ else
+ {
+ baton->locexpr.data = DW_BLOCK (attr)->data;
+ baton->locexpr.size = DW_BLOCK (attr)->size;
+ }
+
prop->data.baton = baton;
prop->kind = PROP_LOCEXPR;
gdb_assert (prop->data.baton != NULL);
@@ -14681,17 +14789,17 @@ read_subrange_type (struct die_info *die, struct dwarf2_cu *cu)
attr = dwarf2_attr (die, DW_AT_lower_bound, cu);
if (attr)
- attr_to_dynamic_prop (attr, die, cu, &low);
+ attr_to_dynamic_prop (attr, die, cu, &low, NULL, 0);
else if (!low_default_is_valid)
complaint (&symfile_complaints, _("Missing DW_AT_lower_bound "
"- DIE at 0x%x [in module %s]"),
die->offset.sect_off, objfile_name (cu->objfile));
attr = dwarf2_attr (die, DW_AT_upper_bound, cu);
- if (!attr_to_dynamic_prop (attr, die, cu, &high))
+ if (!attr_to_dynamic_prop (attr, die, cu, &high, NULL, 0))
{
attr = dwarf2_attr (die, DW_AT_count, cu);
- if (attr_to_dynamic_prop (attr, die, cu, &high))
+ if (attr_to_dynamic_prop (attr, die, cu, &high, NULL, 0))
{
/* If bounds are constant do the final calculation here. */
if (low.kind == PROP_CONST && high.kind == PROP_CONST)
@@ -21695,7 +21803,7 @@ set_die_type (struct die_info *die, struct type *type, struct dwarf2_cu *cu)
{
struct dynamic_prop prop;
- if (attr_to_dynamic_prop (attr, die, cu, &prop))
+ if (attr_to_dynamic_prop (attr, die, cu, &prop, NULL, 0))
{
TYPE_ALLOCATED_PROP (type)
= obstack_alloc (&objfile->objfile_obstack, sizeof (prop));
@@ -21709,7 +21817,7 @@ set_die_type (struct die_info *die, struct type *type, struct dwarf2_cu *cu)
{
struct dynamic_prop prop;
- if (attr_to_dynamic_prop (attr, die, cu, &prop))
+ if (attr_to_dynamic_prop (attr, die, cu, &prop, NULL, 0))
{
TYPE_ASSOCIATED_PROP (type)
= obstack_alloc (&objfile->objfile_obstack, sizeof (prop));
@@ -21719,7 +21827,7 @@ set_die_type (struct die_info *die, struct type *type, struct dwarf2_cu *cu)
/* Read DW_AT_data_location and set in type. */
attr = dwarf2_attr (die, DW_AT_data_location, cu);
- if (attr_to_dynamic_prop (attr, die, cu, &prop))
+ if (attr_to_dynamic_prop (attr, die, cu, &prop, NULL, 0))
{
TYPE_DATA_LOCATION (type)
= obstack_alloc (&objfile->objfile_obstack, sizeof (prop));
--
1.7.9.5