| Message ID | 20190223232954.7185-6-richard.henderson@linaro.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | decodetree enhancements | expand |
On 2/24/19 12:29 AM, Richard Henderson wrote: > Signed-off-by: Richard Henderson <richard.henderson@linaro.org> > --- > docs/decodetree.rst | 58 +++++++++++++++++ > scripts/decodetree.py | 144 ++++++++++++++++++++++++++++++++++++++---- > 2 files changed, 191 insertions(+), 11 deletions(-) > > diff --git a/docs/decodetree.rst b/docs/decodetree.rst > index d9be30b2db..391069c105 100644 > --- a/docs/decodetree.rst > +++ b/docs/decodetree.rst > @@ -154,3 +154,61 @@ which will, in part, invoke:: > and:: > > trans_addl_i(ctx, &arg_opi, insn) > + > +Pattern Groups > +============== > + > +Syntax:: > + > + group := '{' ( pat_def | group )+ '}' > + > +A *group* begins with a lone open-brace, with all subsequent lines > +indented two spaces, and ending with a lone close-brace. Groups > +may be nested, increasing the required indentation of the lines > +within the nested group to two spaces per nesting level. > + > +Unlike ungrouped patterns, grouped patterns are allowed to overlap. > +Conflicts are resolved by selecting the patterns in order. If all > +of the fixedbits for a pattern match, its translate function will > +be called. If the translate function returns false, then subsequent > +patterns within the group will be matched. Excellent! The tibetan cuisine inspired you :P > + > +The following example from PA-RISC shows specialization of the *or* > +instruction:: > + > + { > + { > + nop 000010 ----- ----- 0000 001001 0 00000 > + copy 000010 00000 r1:5 0000 001001 0 rt:5 > + } > + or 000010 r2:5 r1:5 cf:4 001001 0 rt:5 > + } > + > +When the *cf* field is zero, the instruction has no side effects, > +and may be specialized. When the *rt* field is zero, the output > +is discarded and so the instruction has no effect. When the *rt2* *r2*? > +field is zero, the operation is ``reg[rt] | 0`` and so encodes > +the canonical register copy operation. > + > +The output from the generator might look like:: > + > + switch (insn & 0xfc000fe0) { > + case 0x08000240: > + /* 000010.. ........ ....0010 010..... */ > + if ((insn & 0x0000f000) == 0x00000000) { > + /* 000010.. ........ 00000010 010..... */ > + if ((insn & 0x0000001f) == 0x00000000) { > + /* 000010.. ........ 00000010 01000000 */ > + extract_decode_Fmt_0(&u.f_decode0, insn); > + if (trans_nop(ctx, &u.f_decode0)) return true; > + } > + if ((insn & 0x03e00000) == 0x00000000) { > + /* 00001000 000..... 00000010 010..... */ > + extract_decode_Fmt_1(&u.f_decode1, insn); > + if (trans_copy(ctx, &u.f_decode1)) return true; > + } > + } > + extract_decode_Fmt_2(&u.f_decode2, insn); > + if (trans_or(ctx, &u.f_decode2)) return true; > + return false; > + } > diff --git a/scripts/decodetree.py b/scripts/decodetree.py > index dd495096fc..abce58ed8f 100755 > --- a/scripts/decodetree.py > +++ b/scripts/decodetree.py > @@ -31,6 +31,7 @@ fields = {} > arguments = {} > formats = {} > patterns = [] > +allpatterns = [] > > translate_prefix = 'trans' > translate_scope = 'static ' > @@ -353,6 +354,46 @@ class Pattern(General): > # end Pattern > > > +class MultiPattern(General): > + """Class representing an overlapping set of instruction patterns""" > + > + def __init__(self, lineno, pats, fixb, fixm, udfm): > + self.lineno = lineno > + self.pats = pats > + self.base = None > + self.fixedbits = fixb > + self.fixedmask = fixm > + self.undefmask = udfm > + > + def __str__(self): > + r = "{" > + for p in self.pats: > + r = r + ' ' + str(p) > + return r + "}" > + > + def output_decl(self): > + for p in self.pats: > + p.output_decl() > + > + 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 MultiPattern > + > + > def parse_field(lineno, name, toks): > """Parse one instruction field from TOKS at LINENO""" > global fields > @@ -505,6 +546,7 @@ def parse_generic(lineno, is_format, name, toks): > global arguments > global formats > global patterns > + global allpatterns > global re_ident > global insnwidth > global insnmask > @@ -649,6 +691,7 @@ def parse_generic(lineno, is_format, name, toks): > pat = Pattern(name, lineno, fmt, fixedbits, fixedmask, > undefmask, fieldmask, flds) > patterns.append(pat) > + allpatterns.append(pat) > > # Validate the masks that we have assembled. > if fieldmask & fixedmask: > @@ -667,17 +710,61 @@ 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 > + > + for p in pats: > + fixedmask &= p.fixedmask > + undefmask &= p.undefmask > + if p.lineno < lineno: > + lineno = p.lineno > + > + 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: > + error(p.lineno, 'fixedbits mismatch within braces', > + '(0x{0:08x} != 0x{1:08x})'.format(thisbits, fixedbits)) > + > + mp = MultiPattern(lineno, pats, fixedbits, fixedmask, undefmask) > + patterns.append(mp) > +# end build_multi_pattern > > def parse_file(f): > """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 = [] > + > 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: > @@ -687,10 +774,18 @@ def parse_file(f): > if len(toks) != 0: > # Next line after continuation > toks.extend(t) > - elif len(t) == 0: > - # Empty line > - continue > 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? > @@ -698,21 +793,47 @@ def parse_file(f): > toks.pop() > continue > > - if len(toks) < 2: > - error(lineno, 'short line') > - > name = toks[0] > del toks[0] > > + # End nesting? > + if name == '}': > + if nesting == 0: > + error(start_lineno, 'mismatched close brace') > + if len(toks) != 0: > + error(start_lineno, 'extra tokens after close brace') > + nesting -= 2 > + if indent != nesting: > + error(start_lineno, 'indentation ', indent, ' != ', nesting) > + pats = patterns > + patterns = saved_pats.pop() > + build_multi_pattern(lineno, pats) > + toks = [] > + continue > + > + # Everything else should have current indentation. > + if indent != nesting: > + error(start_lineno, 'indentation ', indent, ' != ', nesting) > + > + # Start nesting? > + if name == '{': > + if len(toks) != 0: > + error(start_lineno, 'extra tokens after open brace') > + saved_pats.append(patterns) > + patterns = [] > + nesting += 2 > + toks = [] > + continue > + > # Determine the type of object needing to be parsed. > if name[0] == '%': > - parse_field(lineno, name[1:], toks) > + parse_field(start_lineno, name[1:], toks) > elif name[0] == '&': > - parse_arguments(lineno, name[1:], toks) > + parse_arguments(start_lineno, name[1:], toks) > elif name[0] == '@': > - parse_generic(lineno, True, name[1:], toks) > + parse_generic(start_lineno, True, name[1:], toks) > else: > - parse_generic(lineno, False, name, toks) > + parse_generic(start_lineno, False, name, toks) > toks = [] > # end parse_file > > @@ -846,6 +967,7 @@ def main(): > global arguments > global formats > global patterns > + global allpatterns > global translate_scope > global translate_prefix > global output_fd > @@ -907,7 +1029,7 @@ def main(): > # Make sure that the argument sets are the same, and declare the > # function only once. > out_pats = {} > - for i in patterns: > + for i in allpatterns: > if i.name in out_pats: > p = out_pats[i.name] > if i.base.base != p.base.base: > I'm anxious to test this :)
On 2/24/19 12:29 AM, Richard Henderson wrote: > Signed-off-by: Richard Henderson <richard.henderson@linaro.org> > --- > docs/decodetree.rst | 58 +++++++++++++++++ > scripts/decodetree.py | 144 ++++++++++++++++++++++++++++++++++++++---- > 2 files changed, 191 insertions(+), 11 deletions(-) > > diff --git a/docs/decodetree.rst b/docs/decodetree.rst It would be great to have tests in tests/decode/ that exercise PatternGroups. Cheers, Bastian
diff --git a/docs/decodetree.rst b/docs/decodetree.rst index d9be30b2db..391069c105 100644 --- a/docs/decodetree.rst +++ b/docs/decodetree.rst @@ -154,3 +154,61 @@ which will, in part, invoke:: and:: trans_addl_i(ctx, &arg_opi, insn) + +Pattern Groups +============== + +Syntax:: + + group := '{' ( pat_def | group )+ '}' + +A *group* begins with a lone open-brace, with all subsequent lines +indented two spaces, and ending with a lone close-brace. Groups +may be nested, increasing the required indentation of the lines +within the nested group to two spaces per nesting level. + +Unlike ungrouped patterns, grouped patterns are allowed to overlap. +Conflicts are resolved by selecting the patterns in order. If all +of the fixedbits for a pattern match, its translate function will +be called. If the translate function returns false, then subsequent +patterns within the group will be matched. + +The following example from PA-RISC shows specialization of the *or* +instruction:: + + { + { + nop 000010 ----- ----- 0000 001001 0 00000 + copy 000010 00000 r1:5 0000 001001 0 rt:5 + } + or 000010 r2:5 r1:5 cf:4 001001 0 rt:5 + } + +When the *cf* field is zero, the instruction has no side effects, +and may be specialized. When the *rt* field is zero, the output +is discarded and so the instruction has no effect. When the *rt2* +field is zero, the operation is ``reg[rt] | 0`` and so encodes +the canonical register copy operation. + +The output from the generator might look like:: + + switch (insn & 0xfc000fe0) { + case 0x08000240: + /* 000010.. ........ ....0010 010..... */ + if ((insn & 0x0000f000) == 0x00000000) { + /* 000010.. ........ 00000010 010..... */ + if ((insn & 0x0000001f) == 0x00000000) { + /* 000010.. ........ 00000010 01000000 */ + extract_decode_Fmt_0(&u.f_decode0, insn); + if (trans_nop(ctx, &u.f_decode0)) return true; + } + if ((insn & 0x03e00000) == 0x00000000) { + /* 00001000 000..... 00000010 010..... */ + extract_decode_Fmt_1(&u.f_decode1, insn); + if (trans_copy(ctx, &u.f_decode1)) return true; + } + } + extract_decode_Fmt_2(&u.f_decode2, insn); + if (trans_or(ctx, &u.f_decode2)) return true; + return false; + } diff --git a/scripts/decodetree.py b/scripts/decodetree.py index dd495096fc..abce58ed8f 100755 --- a/scripts/decodetree.py +++ b/scripts/decodetree.py @@ -31,6 +31,7 @@ fields = {} arguments = {} formats = {} patterns = [] +allpatterns = [] translate_prefix = 'trans' translate_scope = 'static ' @@ -353,6 +354,46 @@ class Pattern(General): # end Pattern +class MultiPattern(General): + """Class representing an overlapping set of instruction patterns""" + + def __init__(self, lineno, pats, fixb, fixm, udfm): + self.lineno = lineno + self.pats = pats + self.base = None + self.fixedbits = fixb + self.fixedmask = fixm + self.undefmask = udfm + + def __str__(self): + r = "{" + for p in self.pats: + r = r + ' ' + str(p) + return r + "}" + + def output_decl(self): + for p in self.pats: + p.output_decl() + + 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 MultiPattern + + def parse_field(lineno, name, toks): """Parse one instruction field from TOKS at LINENO""" global fields @@ -505,6 +546,7 @@ def parse_generic(lineno, is_format, name, toks): global arguments global formats global patterns + global allpatterns global re_ident global insnwidth global insnmask @@ -649,6 +691,7 @@ def parse_generic(lineno, is_format, name, toks): pat = Pattern(name, lineno, fmt, fixedbits, fixedmask, undefmask, fieldmask, flds) patterns.append(pat) + allpatterns.append(pat) # Validate the masks that we have assembled. if fieldmask & fixedmask: @@ -667,17 +710,61 @@ 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 + + for p in pats: + fixedmask &= p.fixedmask + undefmask &= p.undefmask + if p.lineno < lineno: + lineno = p.lineno + + 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: + error(p.lineno, 'fixedbits mismatch within braces', + '(0x{0:08x} != 0x{1:08x})'.format(thisbits, fixedbits)) + + mp = MultiPattern(lineno, pats, fixedbits, fixedmask, undefmask) + patterns.append(mp) +# end build_multi_pattern def parse_file(f): """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 = [] + 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: @@ -687,10 +774,18 @@ def parse_file(f): if len(toks) != 0: # Next line after continuation toks.extend(t) - elif len(t) == 0: - # Empty line - continue 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? @@ -698,21 +793,47 @@ def parse_file(f): toks.pop() continue - if len(toks) < 2: - error(lineno, 'short line') - name = toks[0] del toks[0] + # End nesting? + if name == '}': + if nesting == 0: + error(start_lineno, 'mismatched close brace') + if len(toks) != 0: + error(start_lineno, 'extra tokens after close brace') + nesting -= 2 + if indent != nesting: + error(start_lineno, 'indentation ', indent, ' != ', nesting) + pats = patterns + patterns = saved_pats.pop() + build_multi_pattern(lineno, pats) + toks = [] + continue + + # Everything else should have current indentation. + if indent != nesting: + error(start_lineno, 'indentation ', indent, ' != ', nesting) + + # Start nesting? + if name == '{': + if len(toks) != 0: + error(start_lineno, 'extra tokens after open brace') + saved_pats.append(patterns) + patterns = [] + nesting += 2 + toks = [] + continue + # Determine the type of object needing to be parsed. if name[0] == '%': - parse_field(lineno, name[1:], toks) + parse_field(start_lineno, name[1:], toks) elif name[0] == '&': - parse_arguments(lineno, name[1:], toks) + parse_arguments(start_lineno, name[1:], toks) elif name[0] == '@': - parse_generic(lineno, True, name[1:], toks) + parse_generic(start_lineno, True, name[1:], toks) else: - parse_generic(lineno, False, name, toks) + parse_generic(start_lineno, False, name, toks) toks = [] # end parse_file @@ -846,6 +967,7 @@ def main(): global arguments global formats global patterns + global allpatterns global translate_scope global translate_prefix global output_fd @@ -907,7 +1029,7 @@ def main(): # Make sure that the argument sets are the same, and declare the # function only once. out_pats = {} - for i in patterns: + for i in allpatterns: if i.name in out_pats: p = out_pats[i.name] if i.base.base != p.base.base:
Signed-off-by: Richard Henderson <richard.henderson@linaro.org> --- docs/decodetree.rst | 58 +++++++++++++++++ scripts/decodetree.py | 144 ++++++++++++++++++++++++++++++++++++++---- 2 files changed, 191 insertions(+), 11 deletions(-)