diff options
Diffstat (limited to 'scripts/decodetree.py')
| -rwxr-xr-x | scripts/decodetree.py | 511 |
1 files changed, 294 insertions, 217 deletions
diff --git a/scripts/decodetree.py b/scripts/decodetree.py index f9d204aa36..530d41ca62 100755 --- a/scripts/decodetree.py +++ b/scripts/decodetree.py @@ -31,7 +31,6 @@ variablewidth = False fields = {} arguments = {} formats = {} -patterns = [] allpatterns = [] anyextern = False @@ -51,23 +50,27 @@ def error_with_file(file, lineno, *args): global output_file global output_fd + prefix = '' + if file: + prefix += '{0}:'.format(file) if lineno: - r = '{0}:{1}: error:'.format(file, lineno) - elif input_file: - r = '{0}: error:'.format(file) - else: - r = 'error:' - for a in args: - r += ' ' + str(a) - r += '\n' - sys.stderr.write(r) + 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) + error_with_file(input_file, lineno, *args) +# end error + def output(*args): global output_fd @@ -120,6 +123,7 @@ def is_pow2(x): def ctz(x): """Return the number of times 2 factors into X.""" + assert x != 0 r = 0 while ((x >> r) & 1) == 0: r += 1 @@ -127,6 +131,8 @@ def ctz(x): def is_contiguous(bits): + if bits == 0: + return -1 shift = ctz(bits) if is_pow2((bits >> shift) + 1): return shift @@ -364,32 +370,99 @@ class Pattern(General): 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 an overlapping set of instruction patterns""" + """Class representing a set of instruction patterns""" - def __init__(self, lineno, pats, fixb, fixm, udfm, w): + def __init__(self, lineno): self.file = input_file self.lineno = lineno - self.pats = pats + self.pats = [] self.base = None - self.fixedbits = fixb - self.fixedmask = fixm - self.undefmask = udfm - self.width = w + self.fixedbits = 0 + self.fixedmask = 0 + self.undefmask = 0 + self.width = None def __str__(self): - r = "{" - for p in self.pats: - r = r + ' ' + str(p) - return r + "}" + 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) @@ -406,7 +479,154 @@ class MultiPattern(General): output(ind, '}\n') else: p.output_code(i, extracted, p.fixedbits, p.fixedmask) -#end MultiPattern +#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): @@ -565,18 +785,19 @@ def infer_format(arg, fieldmask, flds, width): # end infer_format -def parse_generic(lineno, is_format, name, toks): +def parse_generic(lineno, parent_pat, name, toks): """Parse one instruction format from TOKS at LINENO""" global fields global arguments global formats - global patterns global allpatterns global re_ident global insnwidth global insnmask global variablewidth + is_format = parent_pat is None + fixedmask = 0 fixedbits = 0 undefmask = 0 @@ -727,7 +948,7 @@ def parse_generic(lineno, is_format, name, toks): error(lineno, 'field {0} not initialized'.format(f)) pat = Pattern(name, lineno, fmt, fixedbits, fixedmask, undefmask, fieldmask, flds, width) - patterns.append(pat) + parent_pat.pats.append(pat) allpatterns.append(pat) # Validate the masks that we have assembled. @@ -747,62 +968,16 @@ def parse_generic(lineno, is_format, name, toks): .format(allbits ^ insnmask)) # end parse_general -def build_multi_pattern(lineno, pats): - """Validate the Patterns going into a MultiPattern.""" - global patterns - global insnmask - - if len(pats) < 2: - error(lineno, 'less than two patterns within braces') - - fixedmask = insnmask - undefmask = insnmask - - # Collect fixed/undefmask for all of the children. - # Move the defining lineno back to that of the first child. - for p in pats: - fixedmask &= p.fixedmask - undefmask &= p.undefmask - if p.lineno < lineno: - lineno = p.lineno - - width = None - for p in pats: - if width is None: - width = p.width - elif width != p.width: - error(lineno, 'width mismatch in patterns within braces') - - repeat = True - while repeat: - if fixedmask == 0: - error(lineno, 'no overlap in patterns within braces') - fixedbits = None - for p in pats: - thisbits = p.fixedbits & fixedmask - if fixedbits is None: - fixedbits = thisbits - elif fixedbits != thisbits: - fixedmask &= ~(fixedbits ^ thisbits) - break - else: - repeat = False - mp = MultiPattern(lineno, pats, fixedbits, fixedmask, undefmask, width) - patterns.append(mp) -# end build_multi_pattern - -def parse_file(f): +def parse_file(f, parent_pat): """Parse all of the patterns within a file""" - global patterns - # Read all of the lines of the file. Concatenate lines # ending in backslash; discard empty lines and comments. toks = [] lineno = 0 nesting = 0 - saved_pats = [] + nesting_pats = [] for line in f: lineno += 1 @@ -846,17 +1021,23 @@ def parse_file(f): del toks[0] # End nesting? - if name == '}': - if nesting == 0: - error(start_lineno, 'mismatched close brace') + 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(start_lineno, 'indentation ', indent, ' != ', nesting) - pats = patterns - patterns = saved_pats.pop() - build_multi_pattern(lineno, pats) + error(lineno, 'indentation ', indent, ' != ', nesting) + toks = [] continue @@ -865,11 +1046,18 @@ def parse_file(f): error(start_lineno, 'indentation ', indent, ' != ', nesting) # Start nesting? - if name == '{': + if name == '{' or name == '[': if len(toks) != 0: error(start_lineno, 'extra tokens after open brace') - saved_pats.append(patterns) - patterns = [] + + 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 @@ -880,113 +1068,14 @@ def parse_file(f): elif name[0] == '&': parse_arguments(start_lineno, name[1:], toks) elif name[0] == '@': - parse_generic(start_lineno, True, name[1:], toks) + parse_generic(start_lineno, None, name[1:], toks) else: - parse_generic(start_lineno, False, name, toks) + parse_generic(start_lineno, parent_pat, name, toks) toks = [] -# end parse_file - - -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 - - -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: - 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 = build_tree(l, b | outerbits, fullmask) - t.subs.append((b, s)) - - return t -# end build_tree + if nesting != 0: + error(lineno, 'missing close brace') +# end parse_file class SizeTree: @@ -1130,28 +1219,6 @@ def build_size_tree(pats, width, outerbits, outermask): # end build_size_tree -def prop_format(tree): - """Propagate Format objects into the decode tree""" - - # Depth first search. - for (b, s) in tree.subs: - if isinstance(s, Tree): - 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 -# end prop_format - - def prop_size(tree): """Propagate minimum widths up the decode size tree""" @@ -1172,7 +1239,6 @@ def prop_size(tree): def main(): global arguments global formats - global patterns global allpatterns global translate_scope global translate_prefix @@ -1219,19 +1285,30 @@ def main(): 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) + 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: - stree = build_size_tree(patterns, 8, 0, 0) + for i in toppat.pats: + i.prop_width() + stree = build_size_tree(toppat.pats, 8, 0, 0) prop_size(stree) - dtree = build_tree(patterns, 0, 0) - prop_format(dtree) - if output_file: output_fd = open(output_file, 'w') else: @@ -1289,7 +1366,7 @@ def main(): f = arguments[n] output(i4, i4, f.struct_name(), ' f_', f.name, ';\n') output(i4, '} u;\n\n') - dtree.output_code(4, False, 0, 0) + toppat.output_code(4, False, 0, 0) output(i4, 'return false;\n') output('}\n') |