xref: /openbmc/qemu/scripts/decodetree.py (revision 06831001)
1#!/usr/bin/env python3
2# Copyright (c) 2018 Linaro Limited
3#
4# This library is free software; you can redistribute it and/or
5# modify it under the terms of the GNU Lesser General Public
6# License as published by the Free Software Foundation; either
7# version 2.1 of the License, or (at your option) any later version.
8#
9# This library is distributed in the hope that it will be useful,
10# but WITHOUT ANY WARRANTY; without even the implied warranty of
11# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
12# Lesser General Public License for more details.
13#
14# You should have received a copy of the GNU Lesser General Public
15# License along with this library; if not, see <http://www.gnu.org/licenses/>.
16#
17
18#
19# Generate a decoding tree from a specification file.
20# See the syntax and semantics in docs/devel/decodetree.rst.
21#
22
23import io
24import os
25import re
26import sys
27import getopt
28
29insnwidth = 32
30bitop_width = 32
31insnmask = 0xffffffff
32variablewidth = False
33fields = {}
34arguments = {}
35formats = {}
36allpatterns = []
37anyextern = False
38testforerror = False
39
40translate_prefix = 'trans'
41translate_scope = 'static '
42input_file = ''
43output_file = None
44output_fd = None
45output_null = False
46insntype = 'uint32_t'
47decode_function = 'decode'
48
49# An identifier for C.
50re_C_ident = '[a-zA-Z][a-zA-Z0-9_]*'
51
52# Identifiers for Arguments, Fields, Formats and Patterns.
53re_arg_ident = '&[a-zA-Z0-9_]*'
54re_fld_ident = '%[a-zA-Z0-9_]*'
55re_fmt_ident = '@[a-zA-Z0-9_]*'
56re_pat_ident = '[a-zA-Z0-9_]*'
57
58# Local implementation of a topological sort. We use the same API that
59# the Python graphlib does, so that when QEMU moves forward to a
60# baseline of Python 3.9 or newer this code can all be dropped and
61# replaced with:
62#    from graphlib import TopologicalSorter, CycleError
63#
64# https://docs.python.org/3.9/library/graphlib.html#graphlib.TopologicalSorter
65#
66# We only implement the parts of TopologicalSorter we care about:
67#  ts = TopologicalSorter(graph=None)
68#    create the sorter. graph is a dictionary whose keys are
69#    nodes and whose values are lists of the predecessors of that node.
70#    (That is, if graph contains "A" -> ["B", "C"] then we must output
71#    B and C before A.)
72#  ts.static_order()
73#    returns a list of all the nodes in sorted order, or raises CycleError
74#  CycleError
75#    exception raised if there are cycles in the graph. The second
76#    element in the args attribute is a list of nodes which form a
77#    cycle; the first and last element are the same, eg [a, b, c, a]
78#    (Our implementation doesn't give the order correctly.)
79#
80# For our purposes we can assume that the data set is always small
81# (typically 10 nodes or less, actual links in the graph very rare),
82# so we don't need to worry about efficiency of implementation.
83#
84# The core of this implementation is from
85# https://code.activestate.com/recipes/578272-topological-sort/
86# (but updated to Python 3), and is under the MIT license.
87
88class CycleError(ValueError):
89    """Subclass of ValueError raised if cycles exist in the graph"""
90    pass
91
92class TopologicalSorter:
93    """Topologically sort a graph"""
94    def __init__(self, graph=None):
95        self.graph = graph
96
97    def static_order(self):
98        # We do the sort right here, unlike the stdlib version
99        from functools import reduce
100        data = {}
101        r = []
102
103        if not self.graph:
104            return []
105
106        # This code wants the values in the dict to be specifically sets
107        for k, v in self.graph.items():
108            data[k] = set(v)
109
110        # Find all items that don't depend on anything.
111        extra_items_in_deps = (reduce(set.union, data.values())
112                               - set(data.keys()))
113        # Add empty dependencies where needed
114        data.update({item:{} for item in extra_items_in_deps})
115        while True:
116            ordered = set(item for item, dep in data.items() if not dep)
117            if not ordered:
118                break
119            r.extend(ordered)
120            data = {item: (dep - ordered)
121                    for item, dep in data.items()
122                        if item not in ordered}
123        if data:
124            # This doesn't give as nice results as the stdlib, which
125            # gives you the cycle by listing the nodes in order. Here
126            # we only know the nodes in the cycle but not their order.
127            raise CycleError(f'nodes are in a cycle', list(data.keys()))
128
129        return r
130# end TopologicalSorter
131
132def error_with_file(file, lineno, *args):
133    """Print an error message from file:line and args and exit."""
134    global output_file
135    global output_fd
136
137    prefix = ''
138    if file:
139        prefix += f'{file}:'
140    if lineno:
141        prefix += f'{lineno}:'
142    if prefix:
143        prefix += ' '
144    print(prefix, end='error: ', file=sys.stderr)
145    print(*args, file=sys.stderr)
146
147    if output_file and output_fd:
148        output_fd.close()
149        os.remove(output_file)
150    exit(0 if testforerror else 1)
151# end error_with_file
152
153
154def error(lineno, *args):
155    error_with_file(input_file, lineno, *args)
156# end error
157
158
159def output(*args):
160    global output_fd
161    for a in args:
162        output_fd.write(a)
163
164
165def output_autogen():
166    output('/* This file is autogenerated by scripts/decodetree.py.  */\n\n')
167
168
169def str_indent(c):
170    """Return a string with C spaces"""
171    return ' ' * c
172
173
174def str_fields(fields):
175    """Return a string uniquely identifying FIELDS"""
176    r = ''
177    for n in sorted(fields.keys()):
178        r += '_' + n
179    return r[1:]
180
181
182def whex(val):
183    """Return a hex string for val padded for insnwidth"""
184    global insnwidth
185    return f'0x{val:0{insnwidth // 4}x}'
186
187
188def whexC(val):
189    """Return a hex string for val padded for insnwidth,
190       and with the proper suffix for a C constant."""
191    suffix = ''
192    if val >= 0x100000000:
193        suffix = 'ull'
194    elif val >= 0x80000000:
195        suffix = 'u'
196    return whex(val) + suffix
197
198
199def str_match_bits(bits, mask):
200    """Return a string pretty-printing BITS/MASK"""
201    global insnwidth
202
203    i = 1 << (insnwidth - 1)
204    space = 0x01010100
205    r = ''
206    while i != 0:
207        if i & mask:
208            if i & bits:
209                r += '1'
210            else:
211                r += '0'
212        else:
213            r += '.'
214        if i & space:
215            r += ' '
216        i >>= 1
217    return r
218
219
220def is_pow2(x):
221    """Return true iff X is equal to a power of 2."""
222    return (x & (x - 1)) == 0
223
224
225def ctz(x):
226    """Return the number of times 2 factors into X."""
227    assert x != 0
228    r = 0
229    while ((x >> r) & 1) == 0:
230        r += 1
231    return r
232
233
234def is_contiguous(bits):
235    if bits == 0:
236        return -1
237    shift = ctz(bits)
238    if is_pow2((bits >> shift) + 1):
239        return shift
240    else:
241        return -1
242
243
244def eq_fields_for_args(flds_a, arg):
245    if len(flds_a) != len(arg.fields):
246        return False
247    # Only allow inference on default types
248    for t in arg.types:
249        if t != 'int':
250            return False
251    for k, a in flds_a.items():
252        if k not in arg.fields:
253            return False
254    return True
255
256
257def eq_fields_for_fmts(flds_a, flds_b):
258    if len(flds_a) != len(flds_b):
259        return False
260    for k, a in flds_a.items():
261        if k not in flds_b:
262            return False
263        b = flds_b[k]
264        if a.__class__ != b.__class__ or a != b:
265            return False
266    return True
267
268
269class Field:
270    """Class representing a simple instruction field"""
271    def __init__(self, sign, pos, len):
272        self.sign = sign
273        self.pos = pos
274        self.len = len
275        self.mask = ((1 << len) - 1) << pos
276
277    def __str__(self):
278        if self.sign:
279            s = 's'
280        else:
281            s = ''
282        return str(self.pos) + ':' + s + str(self.len)
283
284    def str_extract(self, lvalue_formatter):
285        global bitop_width
286        s = 's' if self.sign else ''
287        return f'{s}extract{bitop_width}(insn, {self.pos}, {self.len})'
288
289    def referenced_fields(self):
290        return []
291
292    def __eq__(self, other):
293        return self.sign == other.sign and self.mask == other.mask
294
295    def __ne__(self, other):
296        return not self.__eq__(other)
297# end Field
298
299
300class MultiField:
301    """Class representing a compound instruction field"""
302    def __init__(self, subs, mask):
303        self.subs = subs
304        self.sign = subs[0].sign
305        self.mask = mask
306
307    def __str__(self):
308        return str(self.subs)
309
310    def str_extract(self, lvalue_formatter):
311        global bitop_width
312        ret = '0'
313        pos = 0
314        for f in reversed(self.subs):
315            ext = f.str_extract(lvalue_formatter)
316            if pos == 0:
317                ret = ext
318            else:
319                ret = f'deposit{bitop_width}({ret}, {pos}, {bitop_width - pos}, {ext})'
320            pos += f.len
321        return ret
322
323    def referenced_fields(self):
324        l = []
325        for f in self.subs:
326            l.extend(f.referenced_fields())
327        return l
328
329    def __ne__(self, other):
330        if len(self.subs) != len(other.subs):
331            return True
332        for a, b in zip(self.subs, other.subs):
333            if a.__class__ != b.__class__ or a != b:
334                return True
335        return False
336
337    def __eq__(self, other):
338        return not self.__ne__(other)
339# end MultiField
340
341
342class ConstField:
343    """Class representing an argument field with constant value"""
344    def __init__(self, value):
345        self.value = value
346        self.mask = 0
347        self.sign = value < 0
348
349    def __str__(self):
350        return str(self.value)
351
352    def str_extract(self, lvalue_formatter):
353        return str(self.value)
354
355    def referenced_fields(self):
356        return []
357
358    def __cmp__(self, other):
359        return self.value - other.value
360# end ConstField
361
362
363class FunctionField:
364    """Class representing a field passed through a function"""
365    def __init__(self, func, base):
366        self.mask = base.mask
367        self.sign = base.sign
368        self.base = base
369        self.func = func
370
371    def __str__(self):
372        return self.func + '(' + str(self.base) + ')'
373
374    def str_extract(self, lvalue_formatter):
375        return (self.func + '(ctx, '
376                + self.base.str_extract(lvalue_formatter) + ')')
377
378    def referenced_fields(self):
379        return self.base.referenced_fields()
380
381    def __eq__(self, other):
382        return self.func == other.func and self.base == other.base
383
384    def __ne__(self, other):
385        return not self.__eq__(other)
386# end FunctionField
387
388
389class ParameterField:
390    """Class representing a pseudo-field read from a function"""
391    def __init__(self, func):
392        self.mask = 0
393        self.sign = 0
394        self.func = func
395
396    def __str__(self):
397        return self.func
398
399    def str_extract(self, lvalue_formatter):
400        return self.func + '(ctx)'
401
402    def referenced_fields(self):
403        return []
404
405    def __eq__(self, other):
406        return self.func == other.func
407
408    def __ne__(self, other):
409        return not self.__eq__(other)
410# end ParameterField
411
412class NamedField:
413    """Class representing a field already named in the pattern"""
414    def __init__(self, name, sign, len):
415        self.mask = 0
416        self.sign = sign
417        self.len = len
418        self.name = name
419
420    def __str__(self):
421        return self.name
422
423    def str_extract(self, lvalue_formatter):
424        global bitop_width
425        s = 's' if self.sign else ''
426        lvalue = lvalue_formatter(self.name)
427        return f'{s}extract{bitop_width}({lvalue}, 0, {self.len})'
428
429    def referenced_fields(self):
430        return [self.name]
431
432    def __eq__(self, other):
433        return self.name == other.name
434
435    def __ne__(self, other):
436        return not self.__eq__(other)
437# end NamedField
438
439class Arguments:
440    """Class representing the extracted fields of a format"""
441    def __init__(self, nm, flds, types, extern):
442        self.name = nm
443        self.extern = extern
444        self.fields = flds
445        self.types = types
446
447    def __str__(self):
448        return self.name + ' ' + str(self.fields)
449
450    def struct_name(self):
451        return 'arg_' + self.name
452
453    def output_def(self):
454        if not self.extern:
455            output('typedef struct {\n')
456            for (n, t) in zip(self.fields, self.types):
457                output(f'    {t} {n};\n')
458            output('} ', self.struct_name(), ';\n\n')
459# end Arguments
460
461class General:
462    """Common code between instruction formats and instruction patterns"""
463    def __init__(self, name, lineno, base, fixb, fixm, udfm, fldm, flds, w):
464        self.name = name
465        self.file = input_file
466        self.lineno = lineno
467        self.base = base
468        self.fixedbits = fixb
469        self.fixedmask = fixm
470        self.undefmask = udfm
471        self.fieldmask = fldm
472        self.fields = flds
473        self.width = w
474        self.dangling = None
475
476    def __str__(self):
477        return self.name + ' ' + str_match_bits(self.fixedbits, self.fixedmask)
478
479    def str1(self, i):
480        return str_indent(i) + self.__str__()
481
482    def dangling_references(self):
483        # Return a list of all named references which aren't satisfied
484        # directly by this format/pattern. This will be either:
485        #  * a format referring to a field which is specified by the
486        #    pattern(s) using it
487        #  * a pattern referring to a field which is specified by the
488        #    format it uses
489        #  * a user error (referring to a field that doesn't exist at all)
490        if self.dangling is None:
491            # Compute this once and cache the answer
492            dangling = []
493            for n, f in self.fields.items():
494                for r in f.referenced_fields():
495                    if r not in self.fields:
496                        dangling.append(r)
497            self.dangling = dangling
498        return self.dangling
499
500    def output_fields(self, indent, lvalue_formatter):
501        # We use a topological sort to ensure that any use of NamedField
502        # comes after the initialization of the field it is referencing.
503        graph = {}
504        for n, f in self.fields.items():
505            refs = f.referenced_fields()
506            graph[n] = refs
507
508        try:
509            ts = TopologicalSorter(graph)
510            for n in ts.static_order():
511                # We only want to emit assignments for the keys
512                # in our fields list, not for anything that ends up
513                # in the tsort graph only because it was referenced as
514                # a NamedField.
515                try:
516                    f = self.fields[n]
517                    output(indent, lvalue_formatter(n), ' = ',
518                           f.str_extract(lvalue_formatter), ';\n')
519                except KeyError:
520                    pass
521        except CycleError as e:
522            # The second element of args is a list of nodes which form
523            # a cycle (there might be others too, but only one is reported).
524            # Pretty-print it to tell the user.
525            cycle = ' => '.join(e.args[1])
526            error(self.lineno, 'field definitions form a cycle: ' + cycle)
527# end General
528
529
530class Format(General):
531    """Class representing an instruction format"""
532
533    def extract_name(self):
534        global decode_function
535        return decode_function + '_extract_' + self.name
536
537    def output_extract(self):
538        output('static void ', self.extract_name(), '(DisasContext *ctx, ',
539               self.base.struct_name(), ' *a, ', insntype, ' insn)\n{\n')
540        self.output_fields(str_indent(4), lambda n: 'a->' + n)
541        output('}\n\n')
542# end Format
543
544
545class Pattern(General):
546    """Class representing an instruction pattern"""
547
548    def output_decl(self):
549        global translate_scope
550        global translate_prefix
551        output('typedef ', self.base.base.struct_name(),
552               ' arg_', self.name, ';\n')
553        output(translate_scope, 'bool ', translate_prefix, '_', self.name,
554               '(DisasContext *ctx, arg_', self.name, ' *a);\n')
555
556    def output_code(self, i, extracted, outerbits, outermask):
557        global translate_prefix
558        ind = str_indent(i)
559        arg = self.base.base.name
560        output(ind, '/* ', self.file, ':', str(self.lineno), ' */\n')
561        # We might have named references in the format that refer to fields
562        # in the pattern, or named references in the pattern that refer
563        # to fields in the format. This affects whether we extract the fields
564        # for the format before or after the ones for the pattern.
565        # For simplicity we don't allow cross references in both directions.
566        # This is also where we catch the syntax error of referring to
567        # a nonexistent field.
568        fmt_refs = self.base.dangling_references()
569        for r in fmt_refs:
570            if r not in self.fields:
571                error(self.lineno, f'format refers to undefined field {r}')
572        pat_refs = self.dangling_references()
573        for r in pat_refs:
574            if r not in self.base.fields:
575                error(self.lineno, f'pattern refers to undefined field {r}')
576        if pat_refs and fmt_refs:
577            error(self.lineno, ('pattern that uses fields defined in format '
578                                'cannot use format that uses fields defined '
579                                'in pattern'))
580        if fmt_refs:
581            # pattern fields first
582            self.output_fields(ind, lambda n: 'u.f_' + arg + '.' + n)
583            assert not extracted, "dangling fmt refs but it was already extracted"
584        if not extracted:
585            output(ind, self.base.extract_name(),
586                   '(ctx, &u.f_', arg, ', insn);\n')
587        if not fmt_refs:
588            # pattern fields last
589            self.output_fields(ind, lambda n: 'u.f_' + arg + '.' + n)
590
591        output(ind, 'if (', translate_prefix, '_', self.name,
592               '(ctx, &u.f_', arg, ')) return true;\n')
593
594    # Normal patterns do not have children.
595    def build_tree(self):
596        return
597    def prop_masks(self):
598        return
599    def prop_format(self):
600        return
601    def prop_width(self):
602        return
603
604# end Pattern
605
606
607class MultiPattern(General):
608    """Class representing a set of instruction patterns"""
609
610    def __init__(self, lineno):
611        self.file = input_file
612        self.lineno = lineno
613        self.pats = []
614        self.base = None
615        self.fixedbits = 0
616        self.fixedmask = 0
617        self.undefmask = 0
618        self.width = None
619
620    def __str__(self):
621        r = 'group'
622        if self.fixedbits is not None:
623            r += ' ' + str_match_bits(self.fixedbits, self.fixedmask)
624        return r
625
626    def output_decl(self):
627        for p in self.pats:
628            p.output_decl()
629
630    def prop_masks(self):
631        global insnmask
632
633        fixedmask = insnmask
634        undefmask = insnmask
635
636        # Collect fixedmask/undefmask for all of the children.
637        for p in self.pats:
638            p.prop_masks()
639            fixedmask &= p.fixedmask
640            undefmask &= p.undefmask
641
642        # Widen fixedmask until all fixedbits match
643        repeat = True
644        fixedbits = 0
645        while repeat and fixedmask != 0:
646            fixedbits = None
647            for p in self.pats:
648                thisbits = p.fixedbits & fixedmask
649                if fixedbits is None:
650                    fixedbits = thisbits
651                elif fixedbits != thisbits:
652                    fixedmask &= ~(fixedbits ^ thisbits)
653                    break
654            else:
655                repeat = False
656
657        self.fixedbits = fixedbits
658        self.fixedmask = fixedmask
659        self.undefmask = undefmask
660
661    def build_tree(self):
662        for p in self.pats:
663            p.build_tree()
664
665    def prop_format(self):
666        for p in self.pats:
667            p.prop_format()
668
669    def prop_width(self):
670        width = None
671        for p in self.pats:
672            p.prop_width()
673            if width is None:
674                width = p.width
675            elif width != p.width:
676                error_with_file(self.file, self.lineno,
677                                'width mismatch in patterns within braces')
678        self.width = width
679
680# end MultiPattern
681
682
683class IncMultiPattern(MultiPattern):
684    """Class representing an overlapping set of instruction patterns"""
685
686    def output_code(self, i, extracted, outerbits, outermask):
687        global translate_prefix
688        ind = str_indent(i)
689        for p in self.pats:
690            if outermask != p.fixedmask:
691                innermask = p.fixedmask & ~outermask
692                innerbits = p.fixedbits & ~outermask
693                output(ind, f'if ((insn & {whexC(innermask)}) == {whexC(innerbits)}) {{\n')
694                output(ind, f'    /* {str_match_bits(p.fixedbits, p.fixedmask)} */\n')
695                p.output_code(i + 4, extracted, p.fixedbits, p.fixedmask)
696                output(ind, '}\n')
697            else:
698                p.output_code(i, extracted, p.fixedbits, p.fixedmask)
699
700    def build_tree(self):
701        if not self.pats:
702            error_with_file(self.file, self.lineno, 'empty pattern group')
703        super().build_tree()
704
705#end IncMultiPattern
706
707
708class Tree:
709    """Class representing a node in a decode tree"""
710
711    def __init__(self, fm, tm):
712        self.fixedmask = fm
713        self.thismask = tm
714        self.subs = []
715        self.base = None
716
717    def str1(self, i):
718        ind = str_indent(i)
719        r = ind + whex(self.fixedmask)
720        if self.format:
721            r += ' ' + self.format.name
722        r += ' [\n'
723        for (b, s) in self.subs:
724            r += ind + f'  {whex(b)}:\n'
725            r += s.str1(i + 4) + '\n'
726        r += ind + ']'
727        return r
728
729    def __str__(self):
730        return self.str1(0)
731
732    def output_code(self, i, extracted, outerbits, outermask):
733        ind = str_indent(i)
734
735        # If we identified all nodes below have the same format,
736        # extract the fields now. But don't do it if the format relies
737        # on named fields from the insn pattern, as those won't have
738        # been initialised at this point.
739        if not extracted and self.base and not self.base.dangling_references():
740            output(ind, self.base.extract_name(),
741                   '(ctx, &u.f_', self.base.base.name, ', insn);\n')
742            extracted = True
743
744        # Attempt to aid the compiler in producing compact switch statements.
745        # If the bits in the mask are contiguous, extract them.
746        sh = is_contiguous(self.thismask)
747        if sh > 0:
748            # Propagate SH down into the local functions.
749            def str_switch(b, sh=sh):
750                return f'(insn >> {sh}) & {b >> sh:#x}'
751
752            def str_case(b, sh=sh):
753                return hex(b >> sh)
754        else:
755            def str_switch(b):
756                return f'insn & {whexC(b)}'
757
758            def str_case(b):
759                return whexC(b)
760
761        output(ind, 'switch (', str_switch(self.thismask), ') {\n')
762        for b, s in sorted(self.subs):
763            assert (self.thismask & ~s.fixedmask) == 0
764            innermask = outermask | self.thismask
765            innerbits = outerbits | b
766            output(ind, 'case ', str_case(b), ':\n')
767            output(ind, '    /* ',
768                   str_match_bits(innerbits, innermask), ' */\n')
769            s.output_code(i + 4, extracted, innerbits, innermask)
770            output(ind, '    break;\n')
771        output(ind, '}\n')
772# end Tree
773
774
775class ExcMultiPattern(MultiPattern):
776    """Class representing a non-overlapping set of instruction patterns"""
777
778    def output_code(self, i, extracted, outerbits, outermask):
779        # Defer everything to our decomposed Tree node
780        self.tree.output_code(i, extracted, outerbits, outermask)
781
782    @staticmethod
783    def __build_tree(pats, outerbits, outermask):
784        # Find the intersection of all remaining fixedmask.
785        innermask = ~outermask & insnmask
786        for i in pats:
787            innermask &= i.fixedmask
788
789        if innermask == 0:
790            # Edge condition: One pattern covers the entire insnmask
791            if len(pats) == 1:
792                t = Tree(outermask, innermask)
793                t.subs.append((0, pats[0]))
794                return t
795
796            text = 'overlapping patterns:'
797            for p in pats:
798                text += '\n' + p.file + ':' + str(p.lineno) + ': ' + str(p)
799            error_with_file(pats[0].file, pats[0].lineno, text)
800
801        fullmask = outermask | innermask
802
803        # Sort each element of pats into the bin selected by the mask.
804        bins = {}
805        for i in pats:
806            fb = i.fixedbits & innermask
807            if fb in bins:
808                bins[fb].append(i)
809            else:
810                bins[fb] = [i]
811
812        # We must recurse if any bin has more than one element or if
813        # the single element in the bin has not been fully matched.
814        t = Tree(fullmask, innermask)
815
816        for b, l in bins.items():
817            s = l[0]
818            if len(l) > 1 or s.fixedmask & ~fullmask != 0:
819                s = ExcMultiPattern.__build_tree(l, b | outerbits, fullmask)
820            t.subs.append((b, s))
821
822        return t
823
824    def build_tree(self):
825        super().build_tree()
826        self.tree = self.__build_tree(self.pats, self.fixedbits,
827                                      self.fixedmask)
828
829    @staticmethod
830    def __prop_format(tree):
831        """Propagate Format objects into the decode tree"""
832
833        # Depth first search.
834        for (b, s) in tree.subs:
835            if isinstance(s, Tree):
836                ExcMultiPattern.__prop_format(s)
837
838        # If all entries in SUBS have the same format, then
839        # propagate that into the tree.
840        f = None
841        for (b, s) in tree.subs:
842            if f is None:
843                f = s.base
844                if f is None:
845                    return
846            if f is not s.base:
847                return
848        tree.base = f
849
850    def prop_format(self):
851        super().prop_format()
852        self.__prop_format(self.tree)
853
854# end ExcMultiPattern
855
856
857def parse_field(lineno, name, toks):
858    """Parse one instruction field from TOKS at LINENO"""
859    global fields
860    global insnwidth
861    global re_C_ident
862
863    # A "simple" field will have only one entry;
864    # a "multifield" will have several.
865    subs = []
866    width = 0
867    func = None
868    for t in toks:
869        if re.match('^!function=', t):
870            if func:
871                error(lineno, 'duplicate function')
872            func = t.split('=')
873            func = func[1]
874            continue
875
876        if re.fullmatch(re_C_ident + ':s[0-9]+', t):
877            # Signed named field
878            subtoks = t.split(':')
879            n = subtoks[0]
880            le = int(subtoks[1])
881            f = NamedField(n, True, le)
882            subs.append(f)
883            width += le
884            continue
885        if re.fullmatch(re_C_ident + ':[0-9]+', t):
886            # Unsigned named field
887            subtoks = t.split(':')
888            n = subtoks[0]
889            le = int(subtoks[1])
890            f = NamedField(n, False, le)
891            subs.append(f)
892            width += le
893            continue
894
895        if re.fullmatch('[0-9]+:s[0-9]+', t):
896            # Signed field extract
897            subtoks = t.split(':s')
898            sign = True
899        elif re.fullmatch('[0-9]+:[0-9]+', t):
900            # Unsigned field extract
901            subtoks = t.split(':')
902            sign = False
903        else:
904            error(lineno, f'invalid field token "{t}"')
905        po = int(subtoks[0])
906        le = int(subtoks[1])
907        if po + le > insnwidth:
908            error(lineno, f'field {t} too large')
909        f = Field(sign, po, le)
910        subs.append(f)
911        width += le
912
913    if width > insnwidth:
914        error(lineno, 'field too large')
915    if len(subs) == 0:
916        if func:
917            f = ParameterField(func)
918        else:
919            error(lineno, 'field with no value')
920    else:
921        if len(subs) == 1:
922            f = subs[0]
923        else:
924            mask = 0
925            for s in subs:
926                if mask & s.mask:
927                    error(lineno, 'field components overlap')
928                mask |= s.mask
929            f = MultiField(subs, mask)
930        if func:
931            f = FunctionField(func, f)
932
933    if name in fields:
934        error(lineno, 'duplicate field', name)
935    fields[name] = f
936# end parse_field
937
938
939def parse_arguments(lineno, name, toks):
940    """Parse one argument set from TOKS at LINENO"""
941    global arguments
942    global re_C_ident
943    global anyextern
944
945    flds = []
946    types = []
947    extern = False
948    for n in toks:
949        if re.fullmatch('!extern', n):
950            extern = True
951            anyextern = True
952            continue
953        if re.fullmatch(re_C_ident + ':' + re_C_ident, n):
954            (n, t) = n.split(':')
955        elif re.fullmatch(re_C_ident, n):
956            t = 'int'
957        else:
958            error(lineno, f'invalid argument set token "{n}"')
959        if n in flds:
960            error(lineno, f'duplicate argument "{n}"')
961        flds.append(n)
962        types.append(t)
963
964    if name in arguments:
965        error(lineno, 'duplicate argument set', name)
966    arguments[name] = Arguments(name, flds, types, extern)
967# end parse_arguments
968
969
970def lookup_field(lineno, name):
971    global fields
972    if name in fields:
973        return fields[name]
974    error(lineno, 'undefined field', name)
975
976
977def add_field(lineno, flds, new_name, f):
978    if new_name in flds:
979        error(lineno, 'duplicate field', new_name)
980    flds[new_name] = f
981    return flds
982
983
984def add_field_byname(lineno, flds, new_name, old_name):
985    return add_field(lineno, flds, new_name, lookup_field(lineno, old_name))
986
987
988def infer_argument_set(flds):
989    global arguments
990    global decode_function
991
992    for arg in arguments.values():
993        if eq_fields_for_args(flds, arg):
994            return arg
995
996    name = decode_function + str(len(arguments))
997    arg = Arguments(name, flds.keys(), ['int'] * len(flds), False)
998    arguments[name] = arg
999    return arg
1000
1001
1002def infer_format(arg, fieldmask, flds, width):
1003    global arguments
1004    global formats
1005    global decode_function
1006
1007    const_flds = {}
1008    var_flds = {}
1009    for n, c in flds.items():
1010        if c is ConstField:
1011            const_flds[n] = c
1012        else:
1013            var_flds[n] = c
1014
1015    # Look for an existing format with the same argument set and fields
1016    for fmt in formats.values():
1017        if arg and fmt.base != arg:
1018            continue
1019        if fieldmask != fmt.fieldmask:
1020            continue
1021        if width != fmt.width:
1022            continue
1023        if not eq_fields_for_fmts(flds, fmt.fields):
1024            continue
1025        return (fmt, const_flds)
1026
1027    name = decode_function + '_Fmt_' + str(len(formats))
1028    if not arg:
1029        arg = infer_argument_set(flds)
1030
1031    fmt = Format(name, 0, arg, 0, 0, 0, fieldmask, var_flds, width)
1032    formats[name] = fmt
1033
1034    return (fmt, const_flds)
1035# end infer_format
1036
1037
1038def parse_generic(lineno, parent_pat, name, toks):
1039    """Parse one instruction format from TOKS at LINENO"""
1040    global fields
1041    global arguments
1042    global formats
1043    global allpatterns
1044    global re_arg_ident
1045    global re_fld_ident
1046    global re_fmt_ident
1047    global re_C_ident
1048    global insnwidth
1049    global insnmask
1050    global variablewidth
1051
1052    is_format = parent_pat is None
1053
1054    fixedmask = 0
1055    fixedbits = 0
1056    undefmask = 0
1057    width = 0
1058    flds = {}
1059    arg = None
1060    fmt = None
1061    for t in toks:
1062        # '&Foo' gives a format an explicit argument set.
1063        if re.fullmatch(re_arg_ident, t):
1064            tt = t[1:]
1065            if arg:
1066                error(lineno, 'multiple argument sets')
1067            if tt in arguments:
1068                arg = arguments[tt]
1069            else:
1070                error(lineno, 'undefined argument set', t)
1071            continue
1072
1073        # '@Foo' gives a pattern an explicit format.
1074        if re.fullmatch(re_fmt_ident, t):
1075            tt = t[1:]
1076            if fmt:
1077                error(lineno, 'multiple formats')
1078            if tt in formats:
1079                fmt = formats[tt]
1080            else:
1081                error(lineno, 'undefined format', t)
1082            continue
1083
1084        # '%Foo' imports a field.
1085        if re.fullmatch(re_fld_ident, t):
1086            tt = t[1:]
1087            flds = add_field_byname(lineno, flds, tt, tt)
1088            continue
1089
1090        # 'Foo=%Bar' imports a field with a different name.
1091        if re.fullmatch(re_C_ident + '=' + re_fld_ident, t):
1092            (fname, iname) = t.split('=%')
1093            flds = add_field_byname(lineno, flds, fname, iname)
1094            continue
1095
1096        # 'Foo=number' sets an argument field to a constant value
1097        if re.fullmatch(re_C_ident + '=[+-]?[0-9]+', t):
1098            (fname, value) = t.split('=')
1099            value = int(value)
1100            flds = add_field(lineno, flds, fname, ConstField(value))
1101            continue
1102
1103        # Pattern of 0s, 1s, dots and dashes indicate required zeros,
1104        # required ones, or dont-cares.
1105        if re.fullmatch('[01.-]+', t):
1106            shift = len(t)
1107            fms = t.replace('0', '1')
1108            fms = fms.replace('.', '0')
1109            fms = fms.replace('-', '0')
1110            fbs = t.replace('.', '0')
1111            fbs = fbs.replace('-', '0')
1112            ubm = t.replace('1', '0')
1113            ubm = ubm.replace('.', '0')
1114            ubm = ubm.replace('-', '1')
1115            fms = int(fms, 2)
1116            fbs = int(fbs, 2)
1117            ubm = int(ubm, 2)
1118            fixedbits = (fixedbits << shift) | fbs
1119            fixedmask = (fixedmask << shift) | fms
1120            undefmask = (undefmask << shift) | ubm
1121        # Otherwise, fieldname:fieldwidth
1122        elif re.fullmatch(re_C_ident + ':s?[0-9]+', t):
1123            (fname, flen) = t.split(':')
1124            sign = False
1125            if flen[0] == 's':
1126                sign = True
1127                flen = flen[1:]
1128            shift = int(flen, 10)
1129            if shift + width > insnwidth:
1130                error(lineno, f'field {fname} exceeds insnwidth')
1131            f = Field(sign, insnwidth - width - shift, shift)
1132            flds = add_field(lineno, flds, fname, f)
1133            fixedbits <<= shift
1134            fixedmask <<= shift
1135            undefmask <<= shift
1136        else:
1137            error(lineno, f'invalid token "{t}"')
1138        width += shift
1139
1140    if variablewidth and width < insnwidth and width % 8 == 0:
1141        shift = insnwidth - width
1142        fixedbits <<= shift
1143        fixedmask <<= shift
1144        undefmask <<= shift
1145        undefmask |= (1 << shift) - 1
1146
1147    # We should have filled in all of the bits of the instruction.
1148    elif not (is_format and width == 0) and width != insnwidth:
1149        error(lineno, f'definition has {width} bits')
1150
1151    # Do not check for fields overlapping fields; one valid usage
1152    # is to be able to duplicate fields via import.
1153    fieldmask = 0
1154    for f in flds.values():
1155        fieldmask |= f.mask
1156
1157    # Fix up what we've parsed to match either a format or a pattern.
1158    if is_format:
1159        # Formats cannot reference formats.
1160        if fmt:
1161            error(lineno, 'format referencing format')
1162        # If an argument set is given, then there should be no fields
1163        # without a place to store it.
1164        if arg:
1165            for f in flds.keys():
1166                if f not in arg.fields:
1167                    error(lineno, f'field {f} not in argument set {arg.name}')
1168        else:
1169            arg = infer_argument_set(flds)
1170        if name in formats:
1171            error(lineno, 'duplicate format name', name)
1172        fmt = Format(name, lineno, arg, fixedbits, fixedmask,
1173                     undefmask, fieldmask, flds, width)
1174        formats[name] = fmt
1175    else:
1176        # Patterns can reference a format ...
1177        if fmt:
1178            # ... but not an argument simultaneously
1179            if arg:
1180                error(lineno, 'pattern specifies both format and argument set')
1181            if fixedmask & fmt.fixedmask:
1182                error(lineno, 'pattern fixed bits overlap format fixed bits')
1183            if width != fmt.width:
1184                error(lineno, 'pattern uses format of different width')
1185            fieldmask |= fmt.fieldmask
1186            fixedbits |= fmt.fixedbits
1187            fixedmask |= fmt.fixedmask
1188            undefmask |= fmt.undefmask
1189        else:
1190            (fmt, flds) = infer_format(arg, fieldmask, flds, width)
1191        arg = fmt.base
1192        for f in flds.keys():
1193            if f not in arg.fields:
1194                error(lineno, f'field {f} not in argument set {arg.name}')
1195            if f in fmt.fields.keys():
1196                error(lineno, f'field {f} set by format and pattern')
1197        for f in arg.fields:
1198            if f not in flds.keys() and f not in fmt.fields.keys():
1199                error(lineno, f'field {f} not initialized')
1200        pat = Pattern(name, lineno, fmt, fixedbits, fixedmask,
1201                      undefmask, fieldmask, flds, width)
1202        parent_pat.pats.append(pat)
1203        allpatterns.append(pat)
1204
1205    # Validate the masks that we have assembled.
1206    if fieldmask & fixedmask:
1207        error(lineno, 'fieldmask overlaps fixedmask ',
1208              f'({whex(fieldmask)} & {whex(fixedmask)})')
1209    if fieldmask & undefmask:
1210        error(lineno, 'fieldmask overlaps undefmask ',
1211              f'({whex(fieldmask)} & {whex(undefmask)})')
1212    if fixedmask & undefmask:
1213        error(lineno, 'fixedmask overlaps undefmask ',
1214              f'({whex(fixedmask)} & {whex(undefmask)})')
1215    if not is_format:
1216        allbits = fieldmask | fixedmask | undefmask
1217        if allbits != insnmask:
1218            error(lineno, 'bits left unspecified ',
1219                  f'({whex(allbits ^ insnmask)})')
1220# end parse_general
1221
1222
1223def parse_file(f, parent_pat):
1224    """Parse all of the patterns within a file"""
1225    global re_arg_ident
1226    global re_fld_ident
1227    global re_fmt_ident
1228    global re_pat_ident
1229
1230    # Read all of the lines of the file.  Concatenate lines
1231    # ending in backslash; discard empty lines and comments.
1232    toks = []
1233    lineno = 0
1234    nesting = 0
1235    nesting_pats = []
1236
1237    for line in f:
1238        lineno += 1
1239
1240        # Expand and strip spaces, to find indent.
1241        line = line.rstrip()
1242        line = line.expandtabs()
1243        len1 = len(line)
1244        line = line.lstrip()
1245        len2 = len(line)
1246
1247        # Discard comments
1248        end = line.find('#')
1249        if end >= 0:
1250            line = line[:end]
1251
1252        t = line.split()
1253        if len(toks) != 0:
1254            # Next line after continuation
1255            toks.extend(t)
1256        else:
1257            # Allow completely blank lines.
1258            if len1 == 0:
1259                continue
1260            indent = len1 - len2
1261            # Empty line due to comment.
1262            if len(t) == 0:
1263                # Indentation must be correct, even for comment lines.
1264                if indent != nesting:
1265                    error(lineno, 'indentation ', indent, ' != ', nesting)
1266                continue
1267            start_lineno = lineno
1268            toks = t
1269
1270        # Continuation?
1271        if toks[-1] == '\\':
1272            toks.pop()
1273            continue
1274
1275        name = toks[0]
1276        del toks[0]
1277
1278        # End nesting?
1279        if name == '}' or name == ']':
1280            if len(toks) != 0:
1281                error(start_lineno, 'extra tokens after close brace')
1282
1283            # Make sure { } and [ ] nest properly.
1284            if (name == '}') != isinstance(parent_pat, IncMultiPattern):
1285                error(lineno, 'mismatched close brace')
1286
1287            try:
1288                parent_pat = nesting_pats.pop()
1289            except:
1290                error(lineno, 'extra close brace')
1291
1292            nesting -= 2
1293            if indent != nesting:
1294                error(lineno, 'indentation ', indent, ' != ', nesting)
1295
1296            toks = []
1297            continue
1298
1299        # Everything else should have current indentation.
1300        if indent != nesting:
1301            error(start_lineno, 'indentation ', indent, ' != ', nesting)
1302
1303        # Start nesting?
1304        if name == '{' or name == '[':
1305            if len(toks) != 0:
1306                error(start_lineno, 'extra tokens after open brace')
1307
1308            if name == '{':
1309                nested_pat = IncMultiPattern(start_lineno)
1310            else:
1311                nested_pat = ExcMultiPattern(start_lineno)
1312            parent_pat.pats.append(nested_pat)
1313            nesting_pats.append(parent_pat)
1314            parent_pat = nested_pat
1315
1316            nesting += 2
1317            toks = []
1318            continue
1319
1320        # Determine the type of object needing to be parsed.
1321        if re.fullmatch(re_fld_ident, name):
1322            parse_field(start_lineno, name[1:], toks)
1323        elif re.fullmatch(re_arg_ident, name):
1324            parse_arguments(start_lineno, name[1:], toks)
1325        elif re.fullmatch(re_fmt_ident, name):
1326            parse_generic(start_lineno, None, name[1:], toks)
1327        elif re.fullmatch(re_pat_ident, name):
1328            parse_generic(start_lineno, parent_pat, name, toks)
1329        else:
1330            error(lineno, f'invalid token "{name}"')
1331        toks = []
1332
1333    if nesting != 0:
1334        error(lineno, 'missing close brace')
1335# end parse_file
1336
1337
1338class SizeTree:
1339    """Class representing a node in a size decode tree"""
1340
1341    def __init__(self, m, w):
1342        self.mask = m
1343        self.subs = []
1344        self.base = None
1345        self.width = w
1346
1347    def str1(self, i):
1348        ind = str_indent(i)
1349        r = ind + whex(self.mask) + ' [\n'
1350        for (b, s) in self.subs:
1351            r += ind + f'  {whex(b)}:\n'
1352            r += s.str1(i + 4) + '\n'
1353        r += ind + ']'
1354        return r
1355
1356    def __str__(self):
1357        return self.str1(0)
1358
1359    def output_code(self, i, extracted, outerbits, outermask):
1360        ind = str_indent(i)
1361
1362        # If we need to load more bytes to test, do so now.
1363        if extracted < self.width:
1364            output(ind, f'insn = {decode_function}_load_bytes',
1365                   f'(ctx, insn, {extracted // 8}, {self.width // 8});\n')
1366            extracted = self.width
1367
1368        # Attempt to aid the compiler in producing compact switch statements.
1369        # If the bits in the mask are contiguous, extract them.
1370        sh = is_contiguous(self.mask)
1371        if sh > 0:
1372            # Propagate SH down into the local functions.
1373            def str_switch(b, sh=sh):
1374                return f'(insn >> {sh}) & {b >> sh:#x}'
1375
1376            def str_case(b, sh=sh):
1377                return hex(b >> sh)
1378        else:
1379            def str_switch(b):
1380                return f'insn & {whexC(b)}'
1381
1382            def str_case(b):
1383                return whexC(b)
1384
1385        output(ind, 'switch (', str_switch(self.mask), ') {\n')
1386        for b, s in sorted(self.subs):
1387            innermask = outermask | self.mask
1388            innerbits = outerbits | b
1389            output(ind, 'case ', str_case(b), ':\n')
1390            output(ind, '    /* ',
1391                   str_match_bits(innerbits, innermask), ' */\n')
1392            s.output_code(i + 4, extracted, innerbits, innermask)
1393        output(ind, '}\n')
1394        output(ind, 'return insn;\n')
1395# end SizeTree
1396
1397class SizeLeaf:
1398    """Class representing a leaf node in a size decode tree"""
1399
1400    def __init__(self, m, w):
1401        self.mask = m
1402        self.width = w
1403
1404    def str1(self, i):
1405        return str_indent(i) + whex(self.mask)
1406
1407    def __str__(self):
1408        return self.str1(0)
1409
1410    def output_code(self, i, extracted, outerbits, outermask):
1411        global decode_function
1412        ind = str_indent(i)
1413
1414        # If we need to load more bytes, do so now.
1415        if extracted < self.width:
1416            output(ind, f'insn = {decode_function}_load_bytes',
1417                   f'(ctx, insn, {extracted // 8}, {self.width // 8});\n')
1418            extracted = self.width
1419        output(ind, 'return insn;\n')
1420# end SizeLeaf
1421
1422
1423def build_size_tree(pats, width, outerbits, outermask):
1424    global insnwidth
1425
1426    # Collect the mask of bits that are fixed in this width
1427    innermask = 0xff << (insnwidth - width)
1428    innermask &= ~outermask
1429    minwidth = None
1430    onewidth = True
1431    for i in pats:
1432        innermask &= i.fixedmask
1433        if minwidth is None:
1434            minwidth = i.width
1435        elif minwidth != i.width:
1436            onewidth = False;
1437            if minwidth < i.width:
1438                minwidth = i.width
1439
1440    if onewidth:
1441        return SizeLeaf(innermask, minwidth)
1442
1443    if innermask == 0:
1444        if width < minwidth:
1445            return build_size_tree(pats, width + 8, outerbits, outermask)
1446
1447        pnames = []
1448        for p in pats:
1449            pnames.append(p.name + ':' + p.file + ':' + str(p.lineno))
1450        error_with_file(pats[0].file, pats[0].lineno,
1451                        f'overlapping patterns size {width}:', pnames)
1452
1453    bins = {}
1454    for i in pats:
1455        fb = i.fixedbits & innermask
1456        if fb in bins:
1457            bins[fb].append(i)
1458        else:
1459            bins[fb] = [i]
1460
1461    fullmask = outermask | innermask
1462    lens = sorted(bins.keys())
1463    if len(lens) == 1:
1464        b = lens[0]
1465        return build_size_tree(bins[b], width + 8, b | outerbits, fullmask)
1466
1467    r = SizeTree(innermask, width)
1468    for b, l in bins.items():
1469        s = build_size_tree(l, width, b | outerbits, fullmask)
1470        r.subs.append((b, s))
1471    return r
1472# end build_size_tree
1473
1474
1475def prop_size(tree):
1476    """Propagate minimum widths up the decode size tree"""
1477
1478    if isinstance(tree, SizeTree):
1479        min = None
1480        for (b, s) in tree.subs:
1481            width = prop_size(s)
1482            if min is None or min > width:
1483                min = width
1484        assert min >= tree.width
1485        tree.width = min
1486    else:
1487        min = tree.width
1488    return min
1489# end prop_size
1490
1491
1492def main():
1493    global arguments
1494    global formats
1495    global allpatterns
1496    global translate_scope
1497    global translate_prefix
1498    global output_fd
1499    global output_file
1500    global output_null
1501    global input_file
1502    global insnwidth
1503    global insntype
1504    global insnmask
1505    global decode_function
1506    global bitop_width
1507    global variablewidth
1508    global anyextern
1509    global testforerror
1510
1511    decode_scope = 'static '
1512
1513    long_opts = ['decode=', 'translate=', 'output=', 'insnwidth=',
1514                 'static-decode=', 'varinsnwidth=', 'test-for-error',
1515                 'output-null']
1516    try:
1517        (opts, args) = getopt.gnu_getopt(sys.argv[1:], 'o:vw:', long_opts)
1518    except getopt.GetoptError as err:
1519        error(0, err)
1520    for o, a in opts:
1521        if o in ('-o', '--output'):
1522            output_file = a
1523        elif o == '--decode':
1524            decode_function = a
1525            decode_scope = ''
1526        elif o == '--static-decode':
1527            decode_function = a
1528        elif o == '--translate':
1529            translate_prefix = a
1530            translate_scope = ''
1531        elif o in ('-w', '--insnwidth', '--varinsnwidth'):
1532            if o == '--varinsnwidth':
1533                variablewidth = True
1534            insnwidth = int(a)
1535            if insnwidth == 16:
1536                insntype = 'uint16_t'
1537                insnmask = 0xffff
1538            elif insnwidth == 64:
1539                insntype = 'uint64_t'
1540                insnmask = 0xffffffffffffffff
1541                bitop_width = 64
1542            elif insnwidth != 32:
1543                error(0, 'cannot handle insns of width', insnwidth)
1544        elif o == '--test-for-error':
1545            testforerror = True
1546        elif o == '--output-null':
1547            output_null = True
1548        else:
1549            assert False, 'unhandled option'
1550
1551    if len(args) < 1:
1552        error(0, 'missing input file')
1553
1554    toppat = ExcMultiPattern(0)
1555
1556    for filename in args:
1557        input_file = filename
1558        f = open(filename, 'rt', encoding='utf-8')
1559        parse_file(f, toppat)
1560        f.close()
1561
1562    # We do not want to compute masks for toppat, because those masks
1563    # are used as a starting point for build_tree.  For toppat, we must
1564    # insist that decode begins from naught.
1565    for i in toppat.pats:
1566        i.prop_masks()
1567
1568    toppat.build_tree()
1569    toppat.prop_format()
1570
1571    if variablewidth:
1572        for i in toppat.pats:
1573            i.prop_width()
1574        stree = build_size_tree(toppat.pats, 8, 0, 0)
1575        prop_size(stree)
1576
1577    if output_null:
1578        output_fd = open(os.devnull, 'wt', encoding='utf-8', errors="ignore")
1579    elif output_file:
1580        output_fd = open(output_file, 'wt', encoding='utf-8')
1581    else:
1582        output_fd = io.TextIOWrapper(sys.stdout.buffer,
1583                                     encoding=sys.stdout.encoding,
1584                                     errors="ignore")
1585
1586    output_autogen()
1587    for n in sorted(arguments.keys()):
1588        f = arguments[n]
1589        f.output_def()
1590
1591    # A single translate function can be invoked for different patterns.
1592    # Make sure that the argument sets are the same, and declare the
1593    # function only once.
1594    #
1595    # If we're sharing formats, we're likely also sharing trans_* functions,
1596    # but we can't tell which ones.  Prevent issues from the compiler by
1597    # suppressing redundant declaration warnings.
1598    if anyextern:
1599        output("#pragma GCC diagnostic push\n",
1600               "#pragma GCC diagnostic ignored \"-Wredundant-decls\"\n",
1601               "#ifdef __clang__\n"
1602               "#  pragma GCC diagnostic ignored \"-Wtypedef-redefinition\"\n",
1603               "#endif\n\n")
1604
1605    out_pats = {}
1606    for i in allpatterns:
1607        if i.name in out_pats:
1608            p = out_pats[i.name]
1609            if i.base.base != p.base.base:
1610                error(0, i.name, ' has conflicting argument sets')
1611        else:
1612            i.output_decl()
1613            out_pats[i.name] = i
1614    output('\n')
1615
1616    if anyextern:
1617        output("#pragma GCC diagnostic pop\n\n")
1618
1619    for n in sorted(formats.keys()):
1620        f = formats[n]
1621        f.output_extract()
1622
1623    output(decode_scope, 'bool ', decode_function,
1624           '(DisasContext *ctx, ', insntype, ' insn)\n{\n')
1625
1626    i4 = str_indent(4)
1627
1628    if len(allpatterns) != 0:
1629        output(i4, 'union {\n')
1630        for n in sorted(arguments.keys()):
1631            f = arguments[n]
1632            output(i4, i4, f.struct_name(), ' f_', f.name, ';\n')
1633        output(i4, '} u;\n\n')
1634        toppat.output_code(4, False, 0, 0)
1635
1636    output(i4, 'return false;\n')
1637    output('}\n')
1638
1639    if variablewidth:
1640        output('\n', decode_scope, insntype, ' ', decode_function,
1641               '_load(DisasContext *ctx)\n{\n',
1642               '    ', insntype, ' insn = 0;\n\n')
1643        stree.output_code(4, 0, 0, 0)
1644        output('}\n')
1645
1646    if output_file:
1647        output_fd.close()
1648    exit(1 if testforerror else 0)
1649# end main
1650
1651
1652if __name__ == '__main__':
1653    main()
1654