xemu/scripts/decodetree.py
Thomas Huth 7aa12aa215 Remove the CONFIG_PRAGMA_DIAGNOSTIC_AVAILABLE switch
GCC supports "#pragma GCC diagnostic" since version 4.6, and
Clang seems to support it, too, since its early versions 3.x.
That means that our minimum required compiler versions all support
this pragma already and we can remove the test from configure and
all the related #ifdefs in the code.

Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20200710045515.25986-1-thuth@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
2020-07-13 11:40:52 +02:00

1384 lines
40 KiB
Python
Executable File

#!/usr/bin/env python3
# Copyright (c) 2018 Linaro Limited
#
# This library is free software; you can redistribute it and/or
# modify it under the terms of the GNU Lesser General Public
# License as published by the Free Software Foundation; either
# version 2 of the License, or (at your option) any later version.
#
# This library 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
# Lesser General Public License for more details.
#
# You should have received a copy of the GNU Lesser General Public
# License along with this library; if not, see <http://www.gnu.org/licenses/>.
#
#
# Generate a decoding tree from a specification file.
# See the syntax and semantics in docs/devel/decodetree.rst.
#
import os
import re
import sys
import getopt
insnwidth = 32
insnmask = 0xffffffff
variablewidth = False
fields = {}
arguments = {}
formats = {}
allpatterns = []
anyextern = False
translate_prefix = 'trans'
translate_scope = 'static '
input_file = ''
output_file = None
output_fd = None
insntype = 'uint32_t'
decode_function = 'decode'
re_ident = '[a-zA-Z][a-zA-Z0-9_]*'
def error_with_file(file, lineno, *args):
"""Print an error message from file:line and args and exit."""
global output_file
global output_fd
prefix = ''
if file:
prefix += '{0}:'.format(file)
if lineno:
prefix += '{0}:'.format(lineno)
if prefix:
prefix += ' '
print(prefix, end='error: ', file=sys.stderr)
print(*args, file=sys.stderr)
if output_file and output_fd:
output_fd.close()
os.remove(output_file)
exit(1)
# end error_with_file
def error(lineno, *args):
error_with_file(input_file, lineno, *args)
# end error
def output(*args):
global output_fd
for a in args:
output_fd.write(a)
def output_autogen():
output('/* This file is autogenerated by scripts/decodetree.py. */\n\n')
def str_indent(c):
"""Return a string with C spaces"""
return ' ' * c
def str_fields(fields):
"""Return a string uniquely identifing FIELDS"""
r = ''
for n in sorted(fields.keys()):
r += '_' + n
return r[1:]
def str_match_bits(bits, mask):
"""Return a string pretty-printing BITS/MASK"""
global insnwidth
i = 1 << (insnwidth - 1)
space = 0x01010100
r = ''
while i != 0:
if i & mask:
if i & bits:
r += '1'
else:
r += '0'
else:
r += '.'
if i & space:
r += ' '
i >>= 1
return r
def is_pow2(x):
"""Return true iff X is equal to a power of 2."""
return (x & (x - 1)) == 0
def ctz(x):
"""Return the number of times 2 factors into X."""
assert x != 0
r = 0
while ((x >> r) & 1) == 0:
r += 1
return r
def is_contiguous(bits):
if bits == 0:
return -1
shift = ctz(bits)
if is_pow2((bits >> shift) + 1):
return shift
else:
return -1
def eq_fields_for_args(flds_a, flds_b):
if len(flds_a) != len(flds_b):
return False
for k, a in flds_a.items():
if k not in flds_b:
return False
return True
def eq_fields_for_fmts(flds_a, flds_b):
if len(flds_a) != len(flds_b):
return False
for k, a in flds_a.items():
if k not in flds_b:
return False
b = flds_b[k]
if a.__class__ != b.__class__ or a != b:
return False
return True
class Field:
"""Class representing a simple instruction field"""
def __init__(self, sign, pos, len):
self.sign = sign
self.pos = pos
self.len = len
self.mask = ((1 << len) - 1) << pos
def __str__(self):
if self.sign:
s = 's'
else:
s = ''
return str(self.pos) + ':' + s + str(self.len)
def str_extract(self):
if self.sign:
extr = 'sextract32'
else:
extr = 'extract32'
return '{0}(insn, {1}, {2})'.format(extr, self.pos, self.len)
def __eq__(self, other):
return self.sign == other.sign and self.mask == other.mask
def __ne__(self, other):
return not self.__eq__(other)
# end Field
class MultiField:
"""Class representing a compound instruction field"""
def __init__(self, subs, mask):
self.subs = subs
self.sign = subs[0].sign
self.mask = mask
def __str__(self):
return str(self.subs)
def str_extract(self):
ret = '0'
pos = 0
for f in reversed(self.subs):
if pos == 0:
ret = f.str_extract()
else:
ret = 'deposit32({0}, {1}, {2}, {3})' \
.format(ret, pos, 32 - pos, f.str_extract())
pos += f.len
return ret
def __ne__(self, other):
if len(self.subs) != len(other.subs):
return True
for a, b in zip(self.subs, other.subs):
if a.__class__ != b.__class__ or a != b:
return True
return False
def __eq__(self, other):
return not self.__ne__(other)
# end MultiField
class ConstField:
"""Class representing an argument field with constant value"""
def __init__(self, value):
self.value = value
self.mask = 0
self.sign = value < 0
def __str__(self):
return str(self.value)
def str_extract(self):
return str(self.value)
def __cmp__(self, other):
return self.value - other.value
# end ConstField
class FunctionField:
"""Class representing a field passed through a function"""
def __init__(self, func, base):
self.mask = base.mask
self.sign = base.sign
self.base = base
self.func = func
def __str__(self):
return self.func + '(' + str(self.base) + ')'
def str_extract(self):
return self.func + '(ctx, ' + self.base.str_extract() + ')'
def __eq__(self, other):
return self.func == other.func and self.base == other.base
def __ne__(self, other):
return not self.__eq__(other)
# end FunctionField
class ParameterField:
"""Class representing a pseudo-field read from a function"""
def __init__(self, func):
self.mask = 0
self.sign = 0
self.func = func
def __str__(self):
return self.func
def str_extract(self):
return self.func + '(ctx)'
def __eq__(self, other):
return self.func == other.func
def __ne__(self, other):
return not self.__eq__(other)
# end ParameterField
class Arguments:
"""Class representing the extracted fields of a format"""
def __init__(self, nm, flds, extern):
self.name = nm
self.extern = extern
self.fields = sorted(flds)
def __str__(self):
return self.name + ' ' + str(self.fields)
def struct_name(self):
return 'arg_' + self.name
def output_def(self):
if not self.extern:
output('typedef struct {\n')
for n in self.fields:
output(' int ', n, ';\n')
output('} ', self.struct_name(), ';\n\n')
# end Arguments
class General:
"""Common code between instruction formats and instruction patterns"""
def __init__(self, name, lineno, base, fixb, fixm, udfm, fldm, flds, w):
self.name = name
self.file = input_file
self.lineno = lineno
self.base = base
self.fixedbits = fixb
self.fixedmask = fixm
self.undefmask = udfm
self.fieldmask = fldm
self.fields = flds
self.width = w
def __str__(self):
return self.name + ' ' + str_match_bits(self.fixedbits, self.fixedmask)
def str1(self, i):
return str_indent(i) + self.__str__()
# end General
class Format(General):
"""Class representing an instruction format"""
def extract_name(self):
global decode_function
return decode_function + '_extract_' + self.name
def output_extract(self):
output('static void ', self.extract_name(), '(DisasContext *ctx, ',
self.base.struct_name(), ' *a, ', insntype, ' insn)\n{\n')
for n, f in self.fields.items():
output(' a->', n, ' = ', f.str_extract(), ';\n')
output('}\n\n')
# end Format
class Pattern(General):
"""Class representing an instruction pattern"""
def output_decl(self):
global translate_scope
global translate_prefix
output('typedef ', self.base.base.struct_name(),
' arg_', self.name, ';\n')
output(translate_scope, 'bool ', translate_prefix, '_', self.name,
'(DisasContext *ctx, arg_', self.name, ' *a);\n')
def output_code(self, i, extracted, outerbits, outermask):
global translate_prefix
ind = str_indent(i)
arg = self.base.base.name
output(ind, '/* ', self.file, ':', str(self.lineno), ' */\n')
if not extracted:
output(ind, self.base.extract_name(),
'(ctx, &u.f_', arg, ', insn);\n')
for n, f in self.fields.items():
output(ind, 'u.f_', arg, '.', n, ' = ', f.str_extract(), ';\n')
output(ind, 'if (', translate_prefix, '_', self.name,
'(ctx, &u.f_', arg, ')) return true;\n')
# Normal patterns do not have children.
def build_tree(self):
return
def prop_masks(self):
return
def prop_format(self):
return
def prop_width(self):
return
# end Pattern
class MultiPattern(General):
"""Class representing a set of instruction patterns"""
def __init__(self, lineno):
self.file = input_file
self.lineno = lineno
self.pats = []
self.base = None
self.fixedbits = 0
self.fixedmask = 0
self.undefmask = 0
self.width = None
def __str__(self):
r = 'group'
if self.fixedbits is not None:
r += ' ' + str_match_bits(self.fixedbits, self.fixedmask)
return r
def output_decl(self):
for p in self.pats:
p.output_decl()
def prop_masks(self):
global insnmask
fixedmask = insnmask
undefmask = insnmask
# Collect fixedmask/undefmask for all of the children.
for p in self.pats:
p.prop_masks()
fixedmask &= p.fixedmask
undefmask &= p.undefmask
# Widen fixedmask until all fixedbits match
repeat = True
fixedbits = 0
while repeat and fixedmask != 0:
fixedbits = None
for p in self.pats:
thisbits = p.fixedbits & fixedmask
if fixedbits is None:
fixedbits = thisbits
elif fixedbits != thisbits:
fixedmask &= ~(fixedbits ^ thisbits)
break
else:
repeat = False
self.fixedbits = fixedbits
self.fixedmask = fixedmask
self.undefmask = undefmask
def build_tree(self):
for p in self.pats:
p.build_tree()
def prop_format(self):
for p in self.pats:
p.build_tree()
def prop_width(self):
width = None
for p in self.pats:
p.prop_width()
if width is None:
width = p.width
elif width != p.width:
error_with_file(self.file, self.lineno,
'width mismatch in patterns within braces')
self.width = width
# end MultiPattern
class IncMultiPattern(MultiPattern):
"""Class representing an overlapping set of instruction patterns"""
def output_code(self, i, extracted, outerbits, outermask):
global translate_prefix
ind = str_indent(i)
for p in self.pats:
if outermask != p.fixedmask:
innermask = p.fixedmask & ~outermask
innerbits = p.fixedbits & ~outermask
output(ind, 'if ((insn & ',
'0x{0:08x}) == 0x{1:08x}'.format(innermask, innerbits),
') {\n')
output(ind, ' /* ',
str_match_bits(p.fixedbits, p.fixedmask), ' */\n')
p.output_code(i + 4, extracted, p.fixedbits, p.fixedmask)
output(ind, '}\n')
else:
p.output_code(i, extracted, p.fixedbits, p.fixedmask)
#end IncMultiPattern
class Tree:
"""Class representing a node in a decode tree"""
def __init__(self, fm, tm):
self.fixedmask = fm
self.thismask = tm
self.subs = []
self.base = None
def str1(self, i):
ind = str_indent(i)
r = '{0}{1:08x}'.format(ind, self.fixedmask)
if self.format:
r += ' ' + self.format.name
r += ' [\n'
for (b, s) in self.subs:
r += '{0} {1:08x}:\n'.format(ind, b)
r += s.str1(i + 4) + '\n'
r += ind + ']'
return r
def __str__(self):
return self.str1(0)
def output_code(self, i, extracted, outerbits, outermask):
ind = str_indent(i)
# If we identified all nodes below have the same format,
# extract the fields now.
if not extracted and self.base:
output(ind, self.base.extract_name(),
'(ctx, &u.f_', self.base.base.name, ', insn);\n')
extracted = True
# Attempt to aid the compiler in producing compact switch statements.
# If the bits in the mask are contiguous, extract them.
sh = is_contiguous(self.thismask)
if sh > 0:
# Propagate SH down into the local functions.
def str_switch(b, sh=sh):
return '(insn >> {0}) & 0x{1:x}'.format(sh, b >> sh)
def str_case(b, sh=sh):
return '0x{0:x}'.format(b >> sh)
else:
def str_switch(b):
return 'insn & 0x{0:08x}'.format(b)
def str_case(b):
return '0x{0:08x}'.format(b)
output(ind, 'switch (', str_switch(self.thismask), ') {\n')
for b, s in sorted(self.subs):
assert (self.thismask & ~s.fixedmask) == 0
innermask = outermask | self.thismask
innerbits = outerbits | b
output(ind, 'case ', str_case(b), ':\n')
output(ind, ' /* ',
str_match_bits(innerbits, innermask), ' */\n')
s.output_code(i + 4, extracted, innerbits, innermask)
output(ind, ' return false;\n')
output(ind, '}\n')
# end Tree
class ExcMultiPattern(MultiPattern):
"""Class representing a non-overlapping set of instruction patterns"""
def output_code(self, i, extracted, outerbits, outermask):
# Defer everything to our decomposed Tree node
self.tree.output_code(i, extracted, outerbits, outermask)
@staticmethod
def __build_tree(pats, outerbits, outermask):
# Find the intersection of all remaining fixedmask.
innermask = ~outermask & insnmask
for i in pats:
innermask &= i.fixedmask
if innermask == 0:
# Edge condition: One pattern covers the entire insnmask
if len(pats) == 1:
t = Tree(outermask, innermask)
t.subs.append((0, pats[0]))
return t
text = 'overlapping patterns:'
for p in pats:
text += '\n' + p.file + ':' + str(p.lineno) + ': ' + str(p)
error_with_file(pats[0].file, pats[0].lineno, text)
fullmask = outermask | innermask
# Sort each element of pats into the bin selected by the mask.
bins = {}
for i in pats:
fb = i.fixedbits & innermask
if fb in bins:
bins[fb].append(i)
else:
bins[fb] = [i]
# We must recurse if any bin has more than one element or if
# the single element in the bin has not been fully matched.
t = Tree(fullmask, innermask)
for b, l in bins.items():
s = l[0]
if len(l) > 1 or s.fixedmask & ~fullmask != 0:
s = ExcMultiPattern.__build_tree(l, b | outerbits, fullmask)
t.subs.append((b, s))
return t
def build_tree(self):
super().prop_format()
self.tree = self.__build_tree(self.pats, self.fixedbits,
self.fixedmask)
@staticmethod
def __prop_format(tree):
"""Propagate Format objects into the decode tree"""
# Depth first search.
for (b, s) in tree.subs:
if isinstance(s, Tree):
ExcMultiPattern.__prop_format(s)
# If all entries in SUBS have the same format, then
# propagate that into the tree.
f = None
for (b, s) in tree.subs:
if f is None:
f = s.base
if f is None:
return
if f is not s.base:
return
tree.base = f
def prop_format(self):
super().prop_format()
self.__prop_format(self.tree)
# end ExcMultiPattern
def parse_field(lineno, name, toks):
"""Parse one instruction field from TOKS at LINENO"""
global fields
global re_ident
global insnwidth
# A "simple" field will have only one entry;
# a "multifield" will have several.
subs = []
width = 0
func = None
for t in toks:
if re.fullmatch('!function=' + re_ident, t):
if func:
error(lineno, 'duplicate function')
func = t.split('=')
func = func[1]
continue
if re.fullmatch('[0-9]+:s[0-9]+', t):
# Signed field extract
subtoks = t.split(':s')
sign = True
elif re.fullmatch('[0-9]+:[0-9]+', t):
# Unsigned field extract
subtoks = t.split(':')
sign = False
else:
error(lineno, 'invalid field token "{0}"'.format(t))
po = int(subtoks[0])
le = int(subtoks[1])
if po + le > insnwidth:
error(lineno, 'field {0} too large'.format(t))
f = Field(sign, po, le)
subs.append(f)
width += le
if width > insnwidth:
error(lineno, 'field too large')
if len(subs) == 0:
if func:
f = ParameterField(func)
else:
error(lineno, 'field with no value')
else:
if len(subs) == 1:
f = subs[0]
else:
mask = 0
for s in subs:
if mask & s.mask:
error(lineno, 'field components overlap')
mask |= s.mask
f = MultiField(subs, mask)
if func:
f = FunctionField(func, f)
if name in fields:
error(lineno, 'duplicate field', name)
fields[name] = f
# end parse_field
def parse_arguments(lineno, name, toks):
"""Parse one argument set from TOKS at LINENO"""
global arguments
global re_ident
global anyextern
flds = []
extern = False
for t in toks:
if re.fullmatch('!extern', t):
extern = True
anyextern = True
continue
if not re.fullmatch(re_ident, t):
error(lineno, 'invalid argument set token "{0}"'.format(t))
if t in flds:
error(lineno, 'duplicate argument "{0}"'.format(t))
flds.append(t)
if name in arguments:
error(lineno, 'duplicate argument set', name)
arguments[name] = Arguments(name, flds, extern)
# end parse_arguments
def lookup_field(lineno, name):
global fields
if name in fields:
return fields[name]
error(lineno, 'undefined field', name)
def add_field(lineno, flds, new_name, f):
if new_name in flds:
error(lineno, 'duplicate field', new_name)
flds[new_name] = f
return flds
def add_field_byname(lineno, flds, new_name, old_name):
return add_field(lineno, flds, new_name, lookup_field(lineno, old_name))
def infer_argument_set(flds):
global arguments
global decode_function
for arg in arguments.values():
if eq_fields_for_args(flds, arg.fields):
return arg
name = decode_function + str(len(arguments))
arg = Arguments(name, flds.keys(), False)
arguments[name] = arg
return arg
def infer_format(arg, fieldmask, flds, width):
global arguments
global formats
global decode_function
const_flds = {}
var_flds = {}
for n, c in flds.items():
if c is ConstField:
const_flds[n] = c
else:
var_flds[n] = c
# Look for an existing format with the same argument set and fields
for fmt in formats.values():
if arg and fmt.base != arg:
continue
if fieldmask != fmt.fieldmask:
continue
if width != fmt.width:
continue
if not eq_fields_for_fmts(flds, fmt.fields):
continue
return (fmt, const_flds)
name = decode_function + '_Fmt_' + str(len(formats))
if not arg:
arg = infer_argument_set(flds)
fmt = Format(name, 0, arg, 0, 0, 0, fieldmask, var_flds, width)
formats[name] = fmt
return (fmt, const_flds)
# end infer_format
def parse_generic(lineno, parent_pat, name, toks):
"""Parse one instruction format from TOKS at LINENO"""
global fields
global arguments
global formats
global allpatterns
global re_ident
global insnwidth
global insnmask
global variablewidth
is_format = parent_pat is None
fixedmask = 0
fixedbits = 0
undefmask = 0
width = 0
flds = {}
arg = None
fmt = None
for t in toks:
# '&Foo' gives a format an explcit argument set.
if t[0] == '&':
tt = t[1:]
if arg:
error(lineno, 'multiple argument sets')
if tt in arguments:
arg = arguments[tt]
else:
error(lineno, 'undefined argument set', t)
continue
# '@Foo' gives a pattern an explicit format.
if t[0] == '@':
tt = t[1:]
if fmt:
error(lineno, 'multiple formats')
if tt in formats:
fmt = formats[tt]
else:
error(lineno, 'undefined format', t)
continue
# '%Foo' imports a field.
if t[0] == '%':
tt = t[1:]
flds = add_field_byname(lineno, flds, tt, tt)
continue
# 'Foo=%Bar' imports a field with a different name.
if re.fullmatch(re_ident + '=%' + re_ident, t):
(fname, iname) = t.split('=%')
flds = add_field_byname(lineno, flds, fname, iname)
continue
# 'Foo=number' sets an argument field to a constant value
if re.fullmatch(re_ident + '=[+-]?[0-9]+', t):
(fname, value) = t.split('=')
value = int(value)
flds = add_field(lineno, flds, fname, ConstField(value))
continue
# Pattern of 0s, 1s, dots and dashes indicate required zeros,
# required ones, or dont-cares.
if re.fullmatch('[01.-]+', t):
shift = len(t)
fms = t.replace('0', '1')
fms = fms.replace('.', '0')
fms = fms.replace('-', '0')
fbs = t.replace('.', '0')
fbs = fbs.replace('-', '0')
ubm = t.replace('1', '0')
ubm = ubm.replace('.', '0')
ubm = ubm.replace('-', '1')
fms = int(fms, 2)
fbs = int(fbs, 2)
ubm = int(ubm, 2)
fixedbits = (fixedbits << shift) | fbs
fixedmask = (fixedmask << shift) | fms
undefmask = (undefmask << shift) | ubm
# Otherwise, fieldname:fieldwidth
elif re.fullmatch(re_ident + ':s?[0-9]+', t):
(fname, flen) = t.split(':')
sign = False
if flen[0] == 's':
sign = True
flen = flen[1:]
shift = int(flen, 10)
if shift + width > insnwidth:
error(lineno, 'field {0} exceeds insnwidth'.format(fname))
f = Field(sign, insnwidth - width - shift, shift)
flds = add_field(lineno, flds, fname, f)
fixedbits <<= shift
fixedmask <<= shift
undefmask <<= shift
else:
error(lineno, 'invalid token "{0}"'.format(t))
width += shift
if variablewidth and width < insnwidth and width % 8 == 0:
shift = insnwidth - width
fixedbits <<= shift
fixedmask <<= shift
undefmask <<= shift
undefmask |= (1 << shift) - 1
# We should have filled in all of the bits of the instruction.
elif not (is_format and width == 0) and width != insnwidth:
error(lineno, 'definition has {0} bits'.format(width))
# Do not check for fields overlaping fields; one valid usage
# is to be able to duplicate fields via import.
fieldmask = 0
for f in flds.values():
fieldmask |= f.mask
# Fix up what we've parsed to match either a format or a pattern.
if is_format:
# Formats cannot reference formats.
if fmt:
error(lineno, 'format referencing format')
# If an argument set is given, then there should be no fields
# without a place to store it.
if arg:
for f in flds.keys():
if f not in arg.fields:
error(lineno, 'field {0} not in argument set {1}'
.format(f, arg.name))
else:
arg = infer_argument_set(flds)
if name in formats:
error(lineno, 'duplicate format name', name)
fmt = Format(name, lineno, arg, fixedbits, fixedmask,
undefmask, fieldmask, flds, width)
formats[name] = fmt
else:
# Patterns can reference a format ...
if fmt:
# ... but not an argument simultaneously
if arg:
error(lineno, 'pattern specifies both format and argument set')
if fixedmask & fmt.fixedmask:
error(lineno, 'pattern fixed bits overlap format fixed bits')
if width != fmt.width:
error(lineno, 'pattern uses format of different width')
fieldmask |= fmt.fieldmask
fixedbits |= fmt.fixedbits
fixedmask |= fmt.fixedmask
undefmask |= fmt.undefmask
else:
(fmt, flds) = infer_format(arg, fieldmask, flds, width)
arg = fmt.base
for f in flds.keys():
if f not in arg.fields:
error(lineno, 'field {0} not in argument set {1}'
.format(f, arg.name))
if f in fmt.fields.keys():
error(lineno, 'field {0} set by format and pattern'.format(f))
for f in arg.fields:
if f not in flds.keys() and f not in fmt.fields.keys():
error(lineno, 'field {0} not initialized'.format(f))
pat = Pattern(name, lineno, fmt, fixedbits, fixedmask,
undefmask, fieldmask, flds, width)
parent_pat.pats.append(pat)
allpatterns.append(pat)
# Validate the masks that we have assembled.
if fieldmask & fixedmask:
error(lineno, 'fieldmask overlaps fixedmask (0x{0:08x} & 0x{1:08x})'
.format(fieldmask, fixedmask))
if fieldmask & undefmask:
error(lineno, 'fieldmask overlaps undefmask (0x{0:08x} & 0x{1:08x})'
.format(fieldmask, undefmask))
if fixedmask & undefmask:
error(lineno, 'fixedmask overlaps undefmask (0x{0:08x} & 0x{1:08x})'
.format(fixedmask, undefmask))
if not is_format:
allbits = fieldmask | fixedmask | undefmask
if allbits != insnmask:
error(lineno, 'bits left unspecified (0x{0:08x})'
.format(allbits ^ insnmask))
# end parse_general
def parse_file(f, parent_pat):
"""Parse all of the patterns within a file"""
# Read all of the lines of the file. Concatenate lines
# ending in backslash; discard empty lines and comments.
toks = []
lineno = 0
nesting = 0
nesting_pats = []
for line in f:
lineno += 1
# Expand and strip spaces, to find indent.
line = line.rstrip()
line = line.expandtabs()
len1 = len(line)
line = line.lstrip()
len2 = len(line)
# Discard comments
end = line.find('#')
if end >= 0:
line = line[:end]
t = line.split()
if len(toks) != 0:
# Next line after continuation
toks.extend(t)
else:
# Allow completely blank lines.
if len1 == 0:
continue
indent = len1 - len2
# Empty line due to comment.
if len(t) == 0:
# Indentation must be correct, even for comment lines.
if indent != nesting:
error(lineno, 'indentation ', indent, ' != ', nesting)
continue
start_lineno = lineno
toks = t
# Continuation?
if toks[-1] == '\\':
toks.pop()
continue
name = toks[0]
del toks[0]
# End nesting?
if name == '}' or name == ']':
if len(toks) != 0:
error(start_lineno, 'extra tokens after close brace')
# Make sure { } and [ ] nest properly.
if (name == '}') != isinstance(parent_pat, IncMultiPattern):
error(lineno, 'mismatched close brace')
try:
parent_pat = nesting_pats.pop()
except:
error(lineno, 'extra close brace')
nesting -= 2
if indent != nesting:
error(lineno, 'indentation ', indent, ' != ', nesting)
toks = []
continue
# Everything else should have current indentation.
if indent != nesting:
error(start_lineno, 'indentation ', indent, ' != ', nesting)
# Start nesting?
if name == '{' or name == '[':
if len(toks) != 0:
error(start_lineno, 'extra tokens after open brace')
if name == '{':
nested_pat = IncMultiPattern(start_lineno)
else:
nested_pat = ExcMultiPattern(start_lineno)
parent_pat.pats.append(nested_pat)
nesting_pats.append(parent_pat)
parent_pat = nested_pat
nesting += 2
toks = []
continue
# Determine the type of object needing to be parsed.
if name[0] == '%':
parse_field(start_lineno, name[1:], toks)
elif name[0] == '&':
parse_arguments(start_lineno, name[1:], toks)
elif name[0] == '@':
parse_generic(start_lineno, None, name[1:], toks)
else:
parse_generic(start_lineno, parent_pat, name, toks)
toks = []
if nesting != 0:
error(lineno, 'missing close brace')
# end parse_file
class SizeTree:
"""Class representing a node in a size decode tree"""
def __init__(self, m, w):
self.mask = m
self.subs = []
self.base = None
self.width = w
def str1(self, i):
ind = str_indent(i)
r = '{0}{1:08x}'.format(ind, self.mask)
r += ' [\n'
for (b, s) in self.subs:
r += '{0} {1:08x}:\n'.format(ind, b)
r += s.str1(i + 4) + '\n'
r += ind + ']'
return r
def __str__(self):
return self.str1(0)
def output_code(self, i, extracted, outerbits, outermask):
ind = str_indent(i)
# If we need to load more bytes to test, do so now.
if extracted < self.width:
output(ind, 'insn = ', decode_function,
'_load_bytes(ctx, insn, {0}, {1});\n'
.format(extracted // 8, self.width // 8));
extracted = self.width
# Attempt to aid the compiler in producing compact switch statements.
# If the bits in the mask are contiguous, extract them.
sh = is_contiguous(self.mask)
if sh > 0:
# Propagate SH down into the local functions.
def str_switch(b, sh=sh):
return '(insn >> {0}) & 0x{1:x}'.format(sh, b >> sh)
def str_case(b, sh=sh):
return '0x{0:x}'.format(b >> sh)
else:
def str_switch(b):
return 'insn & 0x{0:08x}'.format(b)
def str_case(b):
return '0x{0:08x}'.format(b)
output(ind, 'switch (', str_switch(self.mask), ') {\n')
for b, s in sorted(self.subs):
innermask = outermask | self.mask
innerbits = outerbits | b
output(ind, 'case ', str_case(b), ':\n')
output(ind, ' /* ',
str_match_bits(innerbits, innermask), ' */\n')
s.output_code(i + 4, extracted, innerbits, innermask)
output(ind, '}\n')
output(ind, 'return insn;\n')
# end SizeTree
class SizeLeaf:
"""Class representing a leaf node in a size decode tree"""
def __init__(self, m, w):
self.mask = m
self.width = w
def str1(self, i):
ind = str_indent(i)
return '{0}{1:08x}'.format(ind, self.mask)
def __str__(self):
return self.str1(0)
def output_code(self, i, extracted, outerbits, outermask):
global decode_function
ind = str_indent(i)
# If we need to load more bytes, do so now.
if extracted < self.width:
output(ind, 'insn = ', decode_function,
'_load_bytes(ctx, insn, {0}, {1});\n'
.format(extracted // 8, self.width // 8));
extracted = self.width
output(ind, 'return insn;\n')
# end SizeLeaf
def build_size_tree(pats, width, outerbits, outermask):
global insnwidth
# Collect the mask of bits that are fixed in this width
innermask = 0xff << (insnwidth - width)
innermask &= ~outermask
minwidth = None
onewidth = True
for i in pats:
innermask &= i.fixedmask
if minwidth is None:
minwidth = i.width
elif minwidth != i.width:
onewidth = False;
if minwidth < i.width:
minwidth = i.width
if onewidth:
return SizeLeaf(innermask, minwidth)
if innermask == 0:
if width < minwidth:
return build_size_tree(pats, width + 8, outerbits, outermask)
pnames = []
for p in pats:
pnames.append(p.name + ':' + p.file + ':' + str(p.lineno))
error_with_file(pats[0].file, pats[0].lineno,
'overlapping patterns size {0}:'.format(width), pnames)
bins = {}
for i in pats:
fb = i.fixedbits & innermask
if fb in bins:
bins[fb].append(i)
else:
bins[fb] = [i]
fullmask = outermask | innermask
lens = sorted(bins.keys())
if len(lens) == 1:
b = lens[0]
return build_size_tree(bins[b], width + 8, b | outerbits, fullmask)
r = SizeTree(innermask, width)
for b, l in bins.items():
s = build_size_tree(l, width, b | outerbits, fullmask)
r.subs.append((b, s))
return r
# end build_size_tree
def prop_size(tree):
"""Propagate minimum widths up the decode size tree"""
if isinstance(tree, SizeTree):
min = None
for (b, s) in tree.subs:
width = prop_size(s)
if min is None or min > width:
min = width
assert min >= tree.width
tree.width = min
else:
min = tree.width
return min
# end prop_size
def main():
global arguments
global formats
global allpatterns
global translate_scope
global translate_prefix
global output_fd
global output_file
global input_file
global insnwidth
global insntype
global insnmask
global decode_function
global variablewidth
global anyextern
decode_scope = 'static '
long_opts = ['decode=', 'translate=', 'output=', 'insnwidth=',
'static-decode=', 'varinsnwidth=']
try:
(opts, args) = getopt.getopt(sys.argv[1:], 'o:vw:', long_opts)
except getopt.GetoptError as err:
error(0, err)
for o, a in opts:
if o in ('-o', '--output'):
output_file = a
elif o == '--decode':
decode_function = a
decode_scope = ''
elif o == '--static-decode':
decode_function = a
elif o == '--translate':
translate_prefix = a
translate_scope = ''
elif o in ('-w', '--insnwidth', '--varinsnwidth'):
if o == '--varinsnwidth':
variablewidth = True
insnwidth = int(a)
if insnwidth == 16:
insntype = 'uint16_t'
insnmask = 0xffff
elif insnwidth != 32:
error(0, 'cannot handle insns of width', insnwidth)
else:
assert False, 'unhandled option'
if len(args) < 1:
error(0, 'missing input file')
toppat = ExcMultiPattern(0)
for filename in args:
input_file = filename
f = open(filename, 'r')
parse_file(f, toppat)
f.close()
# We do not want to compute masks for toppat, because those masks
# are used as a starting point for build_tree. For toppat, we must
# insist that decode begins from naught.
for i in toppat.pats:
i.prop_masks()
toppat.build_tree()
toppat.prop_format()
if variablewidth:
for i in toppat.pats:
i.prop_width()
stree = build_size_tree(toppat.pats, 8, 0, 0)
prop_size(stree)
if output_file:
output_fd = open(output_file, 'w')
else:
output_fd = sys.stdout
output_autogen()
for n in sorted(arguments.keys()):
f = arguments[n]
f.output_def()
# A single translate function can be invoked for different patterns.
# Make sure that the argument sets are the same, and declare the
# function only once.
#
# If we're sharing formats, we're likely also sharing trans_* functions,
# but we can't tell which ones. Prevent issues from the compiler by
# suppressing redundant declaration warnings.
if anyextern:
output("#pragma GCC diagnostic push\n",
"#pragma GCC diagnostic ignored \"-Wredundant-decls\"\n",
"#ifdef __clang__\n"
"# pragma GCC diagnostic ignored \"-Wtypedef-redefinition\"\n",
"#endif\n\n")
out_pats = {}
for i in allpatterns:
if i.name in out_pats:
p = out_pats[i.name]
if i.base.base != p.base.base:
error(0, i.name, ' has conflicting argument sets')
else:
i.output_decl()
out_pats[i.name] = i
output('\n')
if anyextern:
output("#pragma GCC diagnostic pop\n\n")
for n in sorted(formats.keys()):
f = formats[n]
f.output_extract()
output(decode_scope, 'bool ', decode_function,
'(DisasContext *ctx, ', insntype, ' insn)\n{\n')
i4 = str_indent(4)
if len(allpatterns) != 0:
output(i4, 'union {\n')
for n in sorted(arguments.keys()):
f = arguments[n]
output(i4, i4, f.struct_name(), ' f_', f.name, ';\n')
output(i4, '} u;\n\n')
toppat.output_code(4, False, 0, 0)
output(i4, 'return false;\n')
output('}\n')
if variablewidth:
output('\n', decode_scope, insntype, ' ', decode_function,
'_load(DisasContext *ctx)\n{\n',
' ', insntype, ' insn = 0;\n\n')
stree.output_code(4, 0, 0, 0)
output('}\n')
if output_file:
output_fd.close()
# end main
if __name__ == '__main__':
main()