binutils-gdb/gdb/gdb-gdb.py.in
Joel Brobecker 7f5331a885 gdb-gdb.py.in: Fix error when printing range type
I noticed that trying to print the contents of a struct main_type
would fail when the type was a TYPE_CODE_RANGE:

    (gdb) p *type.main_type
    $1 = Python Exception <class 'gdb.error'> There is no member named low_undefined.:

And indeed, Python is right, fields "low_undefined" has been removed
from struct range_bounds back in ... 2014! It was done when we introduced
dynamic bounds handling. This patch fixes gdb-gdb.py.in according to
the new structure.

gdb/ChangeLog:

	* gdb-gdb.py.in (StructMainTypePrettyPrinter.bound_img): New method.
	(StructMainTypePrettyPrinter.bounds_img): Use new "bound_img"
	method to compute the bounds of range types. Also print "[evaluated]"
	if the bounds' values come from a dynamic evaluation.
2019-03-26 18:30:21 -04:00

299 lines
11 KiB
Python

# Copyright (C) 2009-2019 Free Software Foundation, Inc.
#
# This file is part of GDB.
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 3 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program. If not, see <http://www.gnu.org/licenses/>.
import gdb
import os.path
class TypeFlag:
"""A class that allows us to store a flag name, its short name,
and its value.
In the GDB sources, struct type has a component called instance_flags
in which the value is the addition of various flags. These flags are
defined by the enumerates type_instance_flag_value. This class helps us
recreate a list with all these flags that is easy to manipulate and sort.
Because all flag names start with TYPE_INSTANCE_FLAG_, a short_name
attribute is provided that strips this prefix.
ATTRIBUTES
name: The enumeration name (eg: "TYPE_INSTANCE_FLAG_CONST").
value: The associated value.
short_name: The enumeration name, with the suffix stripped.
"""
def __init__(self, name, value):
self.name = name
self.value = value
self.short_name = name.replace("TYPE_INSTANCE_FLAG_", '')
def __lt__(self, other):
"""Sort by value order."""
return self.value < other.value
# A list of all existing TYPE_INSTANCE_FLAGS_* enumerations,
# stored as TypeFlags objects. Lazy-initialized.
TYPE_FLAGS = None
class TypeFlagsPrinter:
"""A class that prints a decoded form of an instance_flags value.
This class uses a global named TYPE_FLAGS, which is a list of
all defined TypeFlag values. Using a global allows us to compute
this list only once.
This class relies on a couple of enumeration types being defined.
If not, then printing of the instance_flag is going to be degraded,
but it's not a fatal error.
"""
def __init__(self, val):
self.val = val
def __str__(self):
global TYPE_FLAGS
if TYPE_FLAGS is None:
self.init_TYPE_FLAGS()
if not self.val:
return "0"
if TYPE_FLAGS:
flag_list = [flag.short_name for flag in TYPE_FLAGS
if self.val & flag.value]
else:
flag_list = ["???"]
return "0x%x [%s]" % (self.val, "|".join(flag_list))
def init_TYPE_FLAGS(self):
"""Initialize the TYPE_FLAGS global as a list of TypeFlag objects.
This operation requires the search of a couple of enumeration types.
If not found, a warning is printed on stdout, and TYPE_FLAGS is
set to the empty list.
The resulting list is sorted by increasing value, to facilitate
printing of the list of flags used in an instance_flags value.
"""
global TYPE_FLAGS
TYPE_FLAGS = []
try:
iflags = gdb.lookup_type("enum type_instance_flag_value")
except:
print("Warning: Cannot find enum type_instance_flag_value type.")
print(" `struct type' pretty-printer will be degraded")
return
TYPE_FLAGS = [TypeFlag(field.name, field.enumval)
for field in iflags.fields()]
TYPE_FLAGS.sort()
class StructTypePrettyPrinter:
"""Pretty-print an object of type struct type"""
def __init__(self, val):
self.val = val
def to_string(self):
fields = []
fields.append("pointer_type = %s" % self.val['pointer_type'])
fields.append("reference_type = %s" % self.val['reference_type'])
fields.append("chain = %s" % self.val['reference_type'])
fields.append("instance_flags = %s"
% TypeFlagsPrinter(self.val['instance_flags']))
fields.append("length = %d" % self.val['length'])
fields.append("main_type = %s" % self.val['main_type'])
return "\n{" + ",\n ".join(fields) + "}"
class StructMainTypePrettyPrinter:
"""Pretty-print an objet of type main_type"""
def __init__(self, val):
self.val = val
def flags_to_string(self):
"""struct main_type contains a series of components that
are one-bit ints whose name start with "flag_". For instance:
flag_unsigned, flag_stub, etc. In essence, these components are
really boolean flags, and this method prints a short synthetic
version of the value of all these flags. For instance, if
flag_unsigned and flag_static are the only components set to 1,
this function will return "unsigned|static".
"""
fields = [field.name.replace("flag_", "")
for field in self.val.type.fields()
if field.name.startswith("flag_") and self.val[field.name]]
return "|".join(fields)
def owner_to_string(self):
"""Return an image of component "owner".
"""
if self.val['flag_objfile_owned'] != 0:
return "%s (objfile)" % self.val['owner']['objfile']
else:
return "%s (gdbarch)" % self.val['owner']['gdbarch']
def struct_field_location_img(self, field_val):
"""Return an image of the loc component inside the given field
gdb.Value.
"""
loc_val = field_val['loc']
loc_kind = str(field_val['loc_kind'])
if loc_kind == "FIELD_LOC_KIND_BITPOS":
return 'bitpos = %d' % loc_val['bitpos']
elif loc_kind == "FIELD_LOC_KIND_ENUMVAL":
return 'enumval = %d' % loc_val['enumval']
elif loc_kind == "FIELD_LOC_KIND_PHYSADDR":
return 'physaddr = 0x%x' % loc_val['physaddr']
elif loc_kind == "FIELD_LOC_KIND_PHYSNAME":
return 'physname = %s' % loc_val['physname']
elif loc_kind == "FIELD_LOC_KIND_DWARF_BLOCK":
return 'dwarf_block = %s' % loc_val['dwarf_block']
else:
return 'loc = ??? (unsupported loc_kind value)'
def struct_field_img(self, fieldno):
"""Return an image of the main_type field number FIELDNO.
"""
f = self.val['flds_bnds']['fields'][fieldno]
label = "flds_bnds.fields[%d]:" % fieldno
if f['artificial']:
label += " (artificial)"
fields = []
fields.append("name = %s" % f['name'])
fields.append("type = %s" % f['type'])
fields.append("loc_kind = %s" % f['loc_kind'])
fields.append("bitsize = %d" % f['bitsize'])
fields.append(self.struct_field_location_img(f))
return label + "\n" + " {" + ",\n ".join(fields) + "}"
def bound_img(self, bound_name):
"""Return an image of the given main_type's bound."""
b = self.val['flds_bnds']['bounds'].dereference()[bound_name]
bnd_kind = str(b['kind'])
if bnd_kind == 'PROP_CONST':
return str(b['data']['const_val'])
elif bnd_kind == 'PROP_UNDEFINED':
return '(undefined)'
else:
info = [bnd_kind]
if bound_name == 'high' and b['flag_upper_bound_is_count']:
info.append('upper_bound_is_count')
return '{} ({})'.format(str(b['data']['baton']), ','.join(info))
def bounds_img(self):
"""Return an image of the main_type bounds.
"""
b = self.val['flds_bnds']['bounds'].dereference()
low = self.bound_img('low')
high = self.bound_img('high')
img = "flds_bnds.bounds = {%s, %s}" % (low, high)
if b['flag_bound_evaluated']:
img += ' [evaluated]'
return img
def type_specific_img(self):
"""Return a string image of the main_type type_specific union.
Only the relevant component of that union is printed (based on
the value of the type_specific_kind field.
"""
type_specific_kind = str(self.val['type_specific_field'])
type_specific = self.val['type_specific']
if type_specific_kind == "TYPE_SPECIFIC_NONE":
img = 'type_specific_field = %s' % type_specific_kind
elif type_specific_kind == "TYPE_SPECIFIC_CPLUS_STUFF":
img = "cplus_stuff = %s" % type_specific['cplus_stuff']
elif type_specific_kind == "TYPE_SPECIFIC_GNAT_STUFF":
img = ("gnat_stuff = {descriptive_type = %s}"
% type_specific['gnat_stuff']['descriptive_type'])
elif type_specific_kind == "TYPE_SPECIFIC_FLOATFORMAT":
img = "floatformat[0..1] = %s" % type_specific['floatformat']
elif type_specific_kind == "TYPE_SPECIFIC_FUNC":
img = ("calling_convention = %d"
% type_specific['func_stuff']['calling_convention'])
# tail_call_list is not printed.
elif type_specific_kind == "TYPE_SPECIFIC_SELF_TYPE":
img = "self_type = %s" % type_specific['self_type']
else:
img = ("type_specific = ??? (unknown type_secific_kind: %s)"
% type_specific_kind)
return img
def to_string(self):
"""Return a pretty-printed image of our main_type.
"""
fields = []
fields.append("name = %s" % self.val['name'])
fields.append("code = %s" % self.val['code'])
fields.append("flags = [%s]" % self.flags_to_string())
fields.append("owner = %s" % self.owner_to_string())
fields.append("target_type = %s" % self.val['target_type'])
if self.val['nfields'] > 0:
for fieldno in range(self.val['nfields']):
fields.append(self.struct_field_img(fieldno))
if self.val['code'] == gdb.TYPE_CODE_RANGE:
fields.append(self.bounds_img())
fields.append(self.type_specific_img())
return "\n{" + ",\n ".join(fields) + "}"
class CoreAddrPrettyPrinter:
"""Print CORE_ADDR values as hex."""
def __init__(self, val):
self._val = val
def to_string(self):
return hex(int(self._val))
def type_lookup_function(val):
"""A routine that returns the correct pretty printer for VAL
if appropriate. Returns None otherwise.
"""
if val.type.tag == "type":
return StructTypePrettyPrinter(val)
elif val.type.tag == "main_type":
return StructMainTypePrettyPrinter(val)
elif val.type.name == 'CORE_ADDR':
return CoreAddrPrettyPrinter(val)
return None
def register_pretty_printer(objfile):
"""A routine to register a pretty-printer against the given OBJFILE.
"""
objfile.pretty_printers.append(type_lookup_function)
if __name__ == "__main__":
if gdb.current_objfile() is not None:
# This is the case where this script is being "auto-loaded"
# for a given objfile. Register the pretty-printer for that
# objfile.
register_pretty_printer(gdb.current_objfile())
else:
# We need to locate the objfile corresponding to the GDB
# executable, and register the pretty-printer for that objfile.
# FIXME: The condition used to match the objfile is too simplistic
# and will not work on Windows.
for objfile in gdb.objfiles():
if os.path.basename(objfile.filename) == "gdb":
objfile.pretty_printers.append(type_lookup_function)