Commit Graph
100 Commits
Author SHA1 Message Date
Akim Demaille 5433b0a84b glr: tests: more macros
This will be useful to support changes in glr2.cc.

tests/glr-regression.at
(Incorrect lookahead during deterministic GLR)
(Incorrect lookahead during nondeterministc GLR):
Introduce and use PRINT_LOOKAHEAD.
2021-01-10 17:02:54 +01:00
Akim Demaille 21c812e2f0 glr: tests: formatting changes
* tests/glr-regression.at: here.
Use %empty where applicable.
2021-01-10 17:02:46 +01:00
Akim Demaille 442c8d85aa tests: fix definition for parser class name
* tests/local.at (AT_PARSER_CLASS): Fix it.
And use it.
2021-01-10 12:14:47 +01:00
Akim Demaille 428999c117 CI: disable the installation of dmd
Currently all the builds fail:

    $ mkdir -p ~/dlang && wget https://dlang.org/install.sh -O ~/dlang/install.sh
    --2021-01-10 06:05:39--  https://dlang.org/install.sh
    Resolving dlang.org (dlang.org)... 162.217.114.56, 2607:fc50:1:ff02::5:0
    Connecting to dlang.org (dlang.org)|162.217.114.56|:443... connected.
    ERROR: cannot verify dlang.org's certificate, issued by ‘CN=R3,O=Let's Encrypt,C=US’:
      Unable to locally verify the issuer's authority.
    To connect to dlang.org insecurely, use `--no-check-certificate'.

* .travis.yml: Disable dmd.
2021-01-10 12:14:43 +01:00
Akim Demaille b52a2172a1 tests: remove some redundant tests
* tests/calc.at: Cut the CI some slack.
2021-01-07 18:51:48 +01:00
Akim Demaille f859462658 d: add support for %printer
Currently we display the addresses of the semantic values.  Instead,
print the values.

Add support for YY_USE across languages.

* data/skeletons/c.m4, data/skeletons/d.m4 (b4_use): New.
* data/skeletons/bison.m4 (b4_symbol_actions): Use b4_use to be
portable to D.

Add support for %printer, and use it.

* data/skeletons/d.m4: Instead of duplicating what's already in
c-like.m4, include it.
(b4_symbol_action): New.
Differs from the one in bison.m4 in that it uses yyval/yyloc instead
of *yyvaluep and *yylocationp.

* data/skeletons/lalr1.d (yy_symbol_print): Avoid calls to formatting,
just call write directly.
Use the %printer.
* examples/d/calc/calc.y: Specify a printer.
Enable traces when $YYDEBUG is set.
* tests/calc.at: Fix the use of %printer with D.
2021-01-07 06:31:28 +01:00
Akim Demaille e51e89856a glr2.cc: add support for variants
(Bison) Variants are extremely picky, which makes them both
annoying (lots of micro-details must be taken care of) and
precious (all the micro-details must be taken care of, in particular
object lifetime).

So (i) each time a semantic value is stored, it must be stored in a
place that exists, and (ii) each time a semantic value is discarded,
its place must have been emptied.

Example of (i)

    - new (&yys.value ()) value_type (s->value ());
    + {]b4_variant_if([[
    +   new (&yys.value ()) value_type ();
    +   ]b4_symbol_variant([yy_accessing_symbol (s->yylrState)],
    +                      [yys.value ()], [copy], [s->value ()])], [[
    +   new (&yys.value ()) value_type (s->value ());]])[
    + }

Example of (ii)

      yyparser.yy_destroy_ ("Error: discarding",
    -                       yytoken, &yylval]b4_locations_if([, &yylloc])[);
    +                       yytoken, &yylval]b4_locations_if([, &yylloc])[);]b4_variant_if([[
    + // Value type destructor.
    + ]b4_symbol_variant([[YYTRANSLATE (this->yychar)]], [[yylval]], [[template destroy]])])[
      this->yychar = ]b4_namespace_ref[::]b4_parser_class[::token::]b4_symbol(empty, id)[;

However, in some places we must not be "pure".  In particular:

    glr_stack_item (const glr_stack_item& other) YY_NOEXCEPT YY_NOTHROW
      : is_state_ (other.is_state_)
    {
      std::memcpy (raw_, other.raw_, union_size);
    }

still must use memcpy, because the constructor would change pred, and
it must not.  This constructor is used only when resizing the stack,
in which case pred (which is relative) must not be "adjusted".

The result works, but is messy.  Its verbosity comes from at least two
factors:

- we don't have support for complete symbols (binding kind, value and
  location), and we should at least try to have it.  That simplified
  lalr1.cc a lot.

- I have not tried to be smart and use 'move' when possible.  As a
  consequence many places have 'copy' and then 'destroy'.  That kind
  of clean up can be done once everything appears to be solid.

* data/skeletons/glr2.cc: Be more rigorous in object lifetime.
In particular, don't forget to discard the lookahead when we're done
with it.
Call variant routines where needed.
Deal with plenty of details.
(b4_call_merger): Add support for variants.
Use references in mergers, rather than pointers.

* examples/c++/glr/c++-types.yy: Exercise variants.
2021-01-05 09:28:20 +01:00
Akim Demaille c2a06bf791 glr: strengthen the tests
On some experimentation I was running, the test suite was passing, yet
the example crashed when run in verbose mode.  Let's add this case to
the test suite.

* tests/cxx-type.at: Run all these tests in verbose mode too.
2021-01-05 07:23:44 +01:00
Akim Demaille 8733959954 c++: I'm tired of Flex's warnings
* doc/bison.texi: Disable another warning I'm tired to see.
New releases would be most welcome.
2021-01-03 20:11:48 +01:00
Akim Demaille 31b8b8f179 glr: example: flush the output
* examples/c/glr/c++-types.y: Flush stdout so that the logs (on
stderr) and the effective output (on stdout) mix correctly.
While at it, be a bit more const-correct.
2021-01-03 19:58:23 +01:00
Akim Demaille e2199d0fb2 style: YYUSE is private, make it YY_USE
This macro is not exposed to users, make start it with 'YY_'.

* data/skeletons/bison.m4, data/skeletons/c.m4, data/skeletons/glr.c,
* data/skeletons/glr.cc, data/skeletons/glr2.cc, data/skeletons/lalr1.cc,
* src/parse-gram.c, tests/actions.at, tests/c++.at, tests/headers.at,
* tests/local.at (YYUSE): Rename as...
(YY_USE): this.
2021-01-03 19:57:10 +01:00
Akim Demaille c1884d3002 glr.c: example: use a printer
* examples/c++/glr/c++-types.yy: Here.
2021-01-03 08:14:22 +01:00
Akim Demaille ab1208e263 glr: consistently use the same wording in traces
* data/skeletons/glr.c, data/skeletons/glr2.cc (yyglrReduce): Traces
refer to "state 42", not to "state #42".
2021-01-03 08:14:22 +01:00
Akim Demaille 74d1e881a7 glr2.cc: also equip semantic_option with self check
* data/skeletons/glr2.cc (semantic_option): Add MAGIC_, magic_ and
check_ members.
Use it.
2021-01-02 13:02:34 +01:00
Akim Demaille f30067ed51 glr2.cc: log the execution of deferred actions
See "glr.c: log the execution of deferred actions".

* data/skeletons/glr2.cc (yyuserAction): Take yyk as a new argument.
Rename argument yyn as yyrule for clarity.
Log before and after the user action.
Adjust callers to not call YY_REDUCE_PRINT and YY_SYMBOL_PRINT.
2021-01-02 13:02:19 +01:00
Akim Demaille 630448ba6b glr2.cc: minor clean up
* data/skeletons/glr2.cc (YYUNDEFTOK): Now useless.
Formatting/coding style changes.
2021-01-02 08:28:26 +01:00
Akim Demaille 1283dc7243 glr.c: log the execution of deferred actions
Currently deferred reductions are not "verbose" at all: only immediate
reductions are displayed in the YYDEBUG traces.  I don't understand
why.  Besides it seems actually simpler the install the reduction
traces right around the user action inside yyuserAction rather that
around calls to yyuserAction.

This only trouble is that yyuserAction does not know the stack number
it works on, so we have to pass it.  And pass -1 when we are actually
running on a temporary stack.

The glr example, on "T(x) + y;" as input, adds these logs, which
allow to see when the `<cast>` is built:

     Stack 0 Entering state 26
     Reduced stack 0 by rule 7 (line 108); action deferred.  Now in state 7.
     Stack 0 Entering state 7
     Reading a token
     Next token is token '+' (1.6: )
     Stack 1 Entering state 27
     Reduced stack 1 by rule 13 (line 123); action deferred.  Now in state 12.
     Stack 1 Entering state 12
     Next token is token '+' (1.6: )
     Stack 1 dies.
     Removing dead stacks.
     On stack 0, shifting token '+' (1.6: )
     Stack 0 now in state #14
    +Reducing stack -1 by rule 6 (line 107):
    +   $1 = token identifier (1.3: x)
    +-> $$ = nterm expr (1.3: x)
    +Reducing stack -1 by rule 7 (line 108):
    +   $1 = token typename (1.0: T)
    +   $2 = token '(' (1.2: )
    +   $3 = nterm expr (1.3: x)
    +   $4 = token ')' (1.4: )
    +-> $$ = nterm expr (1.0-3: <cast>(x,T))
     Returning to deterministic operation.

* data/skeletons/glr.c (yyuserAction): Take yyk as a new argument.
Rename argument yyn as yyrule for clarity.
Log before and after the user action.
Adjust callers to not call YY_REDUCE_PRINT and YY_SYMBOL_PRINT.
2021-01-02 07:37:00 +01:00
Akim Demaille e3d4b42f58 glr.c: reorder routines
The next commit wants to use YY_REDUCE_PRINT above its current
definition.  Move it higher.

* data/skeletons/glr.c (yylhsNonterm, YY_REDUCE_PRINT): Make available
earlier.
2021-01-02 07:37:00 +01:00
Akim Demaille f67c1ce937 glr.c: example: use the exact same display as in the C++ example
* examples/c/glr/c++-types.y: Add a space after the commas.
* examples/c/glr/c++-types.test: Adjust expectations.
2021-01-02 07:37:00 +01:00
Akim Demaille 5a4e606275 glr.c: example: several improvements
* examples/c/glr/c++-types.y (node_print): New.
Use YY_LOCATION_PRINT instead of duplicating it.
And actually use it in the action instead of badly duplicating it.
(main): Add proper option support.
* examples/c/glr/c++-types.test: Adjust expectations on locations.
* examples/c++/glr/c++-types.yy: Fix bad iteration.
2021-01-02 07:36:35 +01:00
Akim Demaille 83f2eb3737 glr2.cc: the example requires Bison 3.8
This will save us from generating the position.hh file.

* src/parse-gram.y: Claim we are 3.8.
* examples/c++/glr/c++-types.yy: Require 3.8.
2020-12-31 08:21:25 +01:00
Akim Demaille 3911aba39a %merge: associate it to its first definition, not the latest
Currently each time we meet %merge we record this location as the
defining location (and symbol).  Instead, record the first definition.

In the generated code we go from

    yy0->A = merge (*yy0, *yy1);

to

    yy0->S = merge (*yy0, *yy1);

where S was indeed the first symbol, and in the diagnostics we go from

    glr-regr18.y:30.18-24: error: result type clash on merge function 'merge': <type2> != <type1>
       30 | sym2: sym3 %merge<merge> { $$ = $1; } ;
          |                  ^~~~~~~
    glr-regr18.y:29.18-24: note: previous declaration
       29 | sym1: sym2 %merge<merge> { $$ = $1; } ;
          |                  ^~~~~~~
    glr-regr18.y:31.13-19: error: result type clash on merge function 'merge': <type3> != <type2>
       31 | sym3: %merge<merge> { $$ = 0; } ;
          |             ^~~~~~~
    glr-regr18.y:30.18-24: note: previous declaration
       30 | sym2: sym3 %merge<merge> { $$ = $1; } ;
          |                  ^~~~~~~

to

    glr-regr18.y:30.18-24: error: result type clash on merge function 'merge': <type2> != <type1>
       30 | sym2: sym3 %merge<merge> { $$ = $1; } ;
          |                  ^~~~~~~
    glr-regr18.y:29.18-24: note: previous declaration
       29 | sym1: sym2 %merge<merge> { $$ = $1; } ;
          |                  ^~~~~~~
    glr-regr18.y:31.13-19: error: result type clash on merge function 'merge': <type3> != <type1>
       31 | sym3: %merge<merge> { $$ = 0; } ;
          |             ^~~~~~~
    glr-regr18.y:29.18-24: note: previous declaration
       29 | sym1: sym2 %merge<merge> { $$ = $1; } ;
          |                  ^~~~~~~

where both duplicates are reported against definition 1, rather than
using definition 1 as a reference when diagnosing about definition 2,
and then 2 as a reference for 3.

* src/reader.c (record_merge_function_type): Keep the first definition.
* tests/glr-regression.at: Adjust.
2020-12-31 08:07:34 +01:00
Akim Demaille 8bc45673d5 %merge: test support for api.value.type=union
* tests/glr-regression.at: here.
2020-12-31 08:07:34 +01:00
Akim Demaille fbe5abd23d %merge: fix compatibility with api.value.type=union
Reported by Jot Dot.
https://lists.gnu.org/r/help-bison/2020-12/msg00014.html

* data/skeletons/glr.c, data/skeletons/glr2.cc (b4_call_merger): Use
the symbol's slot, not its type.
* examples/c/glr/c++-types.y: Use explicit per-symbol typing together
with api.value.type=union.
(yylex): Use yytoken_kind_t.
2020-12-31 08:07:25 +01:00
Akim Demaille c09f2e4c7b %merge: delegate the generation of calls to mergers to m4
Don't generate C code from bison, leave that to the skeletons.

* src/output.c (merger_output): Emit invocations to b4_call_merger.
* data/skeletons/glr.c, data/skeletons/glr2.cc (b4_call_merger): New.
2020-12-31 08:07:11 +01:00
Akim Demaille ac3d5b76f7 %merge: let mergers record a typing-symbol, rather than a type
Symbols are richer than types, and in M4 it is my simpler (and more
common) to deal with symbols rather than types.  So let's associate
mergers to a symbol rather than a type name.

* src/reader.h (merger_list): Replace the 'type' member by a symbol
member.
* src/reader.c (record_merge_function_type): Take a symbol as
argument, rather than a type name.
* src/output.c (merger_output): Adjust.
2020-12-31 08:07:11 +01:00
Akim Demaille edfcca8481 %merge: clearer tests on diagnostics
* tests/glr-regression.at: Use caret errors.
2020-12-31 08:07:11 +01:00
Akim Demaille 92e943bd24 glr2.cc: style: quoting changes
* data/skeletons/glr2.cc: Use stricter quoting rules.
2020-12-28 08:20:22 +01:00
Akim Demaille e40da7b6b3 lalr1.cc: style: quoting changes
* data/skeletons/lalr1.cc: here.
2020-12-28 08:20:16 +01:00
Akim Demaille 70b3c8fb20 glr2.cc: use references to the stack rather than pointers
Now that the lookahead macros (that used yystackp) are out of the way,
there is no reason to continue using a pointer.

* data/skeletons/glr2.cc: Use yystack, a reference, rather that
yystackp, a pointer.
Fix tons of const-correctness issues.
2020-12-27 08:50:10 +01:00
Akim Demaille e9b7641cca glr2.cc: simplify names
Now that we no longer play dangerous games with macros, we can give
the lookahead's token kind its proper name.  The content of yychar
_is_ raw (as opposed to yytoken), there's no reason to pleonasmicate
it (and thus to neologize).

* data/skeletons/glr2.cc (glr_stack::yyrawchar): Rename as...
(glr_stack::yychar): this.
2020-12-27 08:36:20 +01:00
Akim Demaille 321fac2193 glr2.cc: get rid of the macros wrapping the lookahead
In glr.c, the macros yychar, yylval and yylloc allow to deal with
api.pure: sometimes they point to global variables (impure), sometimes
they point to the member variables (pure).

There's no room for globals in glr2.cc.  Besides, they map yychar to
yyrawchar, yylval to yyval, etc. which obfuscates what is actually
going on.

* data/skeletons/glr2.cc (glr_stack::yyval, glr_stack::yyloc): Rename
as...
(glr_stack::yylval, glr_stack::yylloc): these, for clarity.
(yynerrs, yychar, yylval, yylloc, yystackp): Remove these macros.
(b4_yygetToken_call): Remove.
2020-12-27 08:34:49 +01:00
Akim Demaille 2777b73166 glr2.cc: reorganize the skeleton
Restore a more natural order: first define the macros and then use
them.  Currently, some macros were defined between the moment the
header is issued, and then the implementation file.  As a result, it
was possible for the header and the implementation to not use the same
versions of the macros.

* data/skeletons/glr2.cc: Define the macros first, then use them.
* data/skeletons/lalr1.cc: Minor comment and quoting changes.
2020-12-26 18:06:02 +01:00
Akim Demaille 89296e3962 glr2.cc: example: simplify
* examples/c++/glr/c++-types.yy: Formatting changes.
Remove unused support for '@'.
* examples/c/glr/c++-types.y: Ditto.
2020-12-26 17:40:18 +01:00
Akim Demaille bb97a2a37b glr2.cc: make yyreportTree a member function of semantic_option
* data/skeletons/glr2.cc (yy_accessing_symbol, yylhsNonterm): Define
ealier.
(state_stack::yyreportTree): Move to...
(semantic_option::yyreportTree): here.
Adjust dependencies.
2020-12-26 15:40:36 +01:00
Akim Demaille 8a22b557b9 glr2.cc: pass references to yyreportAmbiguity
* data/skeletons/glr2.cc (yyreportAmbiguity): Use references.
2020-12-26 15:40:33 +01:00
Akim Demaille 92dc8bf23b style: use yyval only, not yysval
* data/skeletons/glr.c, data/skeletons/glr2.cc: Use yyval, as in
the other skeletons.
2020-12-26 14:26:23 +01:00
Akim Demaille c18dbfcb06 glr2.cc: pass location by const ref to yyglrShift
* data/skeletons/glr2.cc (glr_state.yyglrShift): Take the location by
const&.
Remove useless `inline`.
2020-12-26 14:26:23 +01:00
Akim Demaille 94701b4e5e style: rename semanticVal as value
* data/skeletons/README-D.txt: Remove, now useless and obsolete.
* data/skeletons/glr2.cc, examples/d/calc/calc.y,
* tests/calc.at, tests/d.at, tests/scanner.at (semanticVal): Replace
with...
(value): this.
2020-12-26 14:26:23 +01:00
Akim Demaille 3e6826aff1 glr2.cc: remove dead comments
* data/skeletons/glr2.cc: We no longer wrap glr.c here.
2020-12-26 14:26:23 +01:00
Akim Demaille 9466c734c5 glr2.cc: use YYCDEBUG, not YY_DEBUG_STREAM
* data/skeletons/glr2.cc (YY_DEBUG_STREAM): Rename as...
(YYCDEBUG): this, as in lalr1.cc.
2020-12-26 14:26:22 +01:00
Akim Demaille b9a533d63e glr2.cc: formatting changes
* data/skeletons/glr2.cc: here.
Remove useless `inline`.
2020-12-26 14:26:22 +01:00
Akim Demaille d0e44162b5 glr2.cc: don't use YYSTYPE/YYLTYPE at all
* data/skeletons/glr2.cc: Define value_type and location_type where
needed, and use them only.
(yyuserMerge): Make it a member function of the glr_state class.
2020-12-26 11:55:01 +01:00
Akim Demaille 8db99c54f4 tests: don't require YYSTYPE/YYLTYPE to be defined in C++
* tests/glr-regression.at: Use AT_YYSTYPE/AT_YYLTYPE to generate
yy::parser::value_type and yy::parser::location_type in C++.
2020-12-26 11:55:01 +01:00
Akim Demaille 2157ced3dd c++: rename semantic_type as value_type
We always refer to the triplet "kind, value, location".  All of them
are nouns, and we support api.value.type and api.location.type.  On
this regard, "semantic_type" was a poor choice.  Make it "value_type".

The test suite was not updated to use value_type, on purpose, to
enforce backward compatibility.

* data/skeletons/c++.m4, data/skeletons/glr.cc, data/skeletons/glr2.cc,
* data/skeletons/variant.hh, doc/bison.texi: Define value_type rather
than semantic_type.
Add a backward compatibility typedef.
* examples/c++/glr/c++-types.yy: Migrate.
2020-12-26 09:05:45 +01:00
Akim Demaille 59653c8efd doc: more about sanitizers
* README-hacking.md: here.
2020-12-26 08:08:06 +01:00
Akim Demaille 2a07cb0f2d glr2.cc: simplify
* data/skeletons/glr2.cc (glr_state_set::yyremoveDeletes): Use
vector::resize rather than vector::erase.
(glr_state::copyFrom): Merge into...
(glr_state::operator=): here.
Valentin wanted each assignment to be explicit, hence copyFrom rather
that operator=.  But in 0a82316e54
(glr2.cc: example: use objects (not pointers) to represent the AST),
in order to get real objects to be processed correctly, we had to
introduce the assignment operator.  Afterward, we also introduced a
full implementation of the copy-ctor, independent of copyFrom.  As a
result, today the only invocation of copyFrom is from the assignment
operator.  Simplify this.
2020-12-26 07:54:44 +01:00
Akim Demaille 734ce73bf2 glr2.cc: fix warnings about uninitialized locations
With GCC10, the CI shows tons of warnings such as
(327. actions.at:374: testing Initial location: glr2.cc):

    input.cc: In member function 'YYRESULTTAG glr_stack::yyglrReduce(state_set_index, rule_num, bool)':
    input.cc:1357:11: error: '<anonymous>.glr_state::yyloc' may be used uninitialized in this function [-Werror=maybe-uninitialized]
     1357 |     yyloc = other.yyloc;
          |     ~~~~~~^~~~~~~~~~~~~

This is because we don't have the constructors for locations.  But we
should have them!  That's only because of glr.cc that ctors were not
enabled by default.  In glr2.cc, they should.

That fixes all the warnings when Bison's locations are used.  However,
when user-defined locations without constructor are used, we still
have:

    550. calc.at:1409: testing Calculator glr2.cc %locations api.location.type={Span}  ...
    calc.cc: In member function 'YYRESULTTAG glr_stack::yyglrReduce(state_set_index, rule_num, bool)':
    calc.cc:1261:11: error: '<anonymous>.glr_state::yyloc' may be used uninitialized in this function [-Werror=maybe-uninitialized]
     1261 |     yyloc = other.yyloc;
          |     ~~~~~~^~~~~~~~~~~~~

To address this case, we need glr_state to explicily initialize its
yyloc member.

* data/skeletons/glr2.cc: Use genuine objects, with ctors, for position
and location.
(glr_state): Explicitly initialize yyloc in the constructors.
2020-12-26 07:54:05 +01:00
Akim Demaille baea8cf9fa glr2.cc: provide glr_state with a genuine copy-constructor
The copy constructor was (lazily) implemented by a call to copyFrom.
Unfortunately copyFrom reads yyresolved from the destination (and
source), and in the case of the copy-ctor this is random garbagge,
which UBSAN catches:

    glr-regr2a.cc:1072:10: runtime error: load of value 7, which is not a valid value for type 'bool'

Rather than defining yyresolved before calling copyFrom, let's just
provide a genuine cpy-ctor for glr_state.

* data/skeletons/glr2.cc (glr_state::glr_state): Implement properly.
2020-12-25 11:04:53 +01:00
Akim Demaille 636c9a8042 glr2.cc: beware of self-assignment
In yycompressStack:

    while (yyr != YY_NULLPTR)
      {
        nextFreeItem->check_ ();
        yyr->check_();
        nextFreeItem->setState(*yyr);
        glr_state& nextFreeState = nextFreeItem->getState();
        yyr = yyr->pred();
        nextFreeState.setPred(&(nextFreeItem - 1)->getState());
        setFirstTop(&nextFreeState);
        ++nextFreeItem;
      }

it is possible that nextFreeItem and yyr are actually the same state.
In which case `nextFreeItem->setState(*yyr)` does really bad things.

* data/skeletons/glr2.cc (glr_stack_item::setState): Beware of
self-assignment.
2020-12-25 11:04:53 +01:00
Akim Demaille 7dc942dca3 glr: comment changes
* data/skeletons/glr.c: A bit more doc.
(yypstates): Rename yyst (only occurrence) to yys (commonly used for
yyGLRState).
* data/skeletons/glr2.cc: Ditto.
Prefer '\n' to "\n".
2020-12-25 11:04:33 +01:00
Akim Demaille c0f3b55b25 style: address syntax-check diagnostics
* examples/c/glr/c++-types.y: Formatting changes.
* po/POTFILES.in: Add missing files.
* src/reader.c: Remove useless include.
* tests/calc.at: Avoid magic values for exit.
Obfuscate calls to error.
2020-12-21 07:51:02 +01:00
Akim Demaille c6a39f8409 glr2.cc: formatting changes
* data/skeletons/glr2.cc (glr_state): here.
(glr_state::MAGIC): Make it easier to recognize in decimal.
2020-12-20 18:49:06 +01:00
Akim Demaille df34ad7c6e glr2.cc: call the destructor in a way that complies with clang
examples/c++/glr/c++-types.cc:721:24: error:
      expected the class name after '~' to name a destructor
    yysval.YYSTYPE::~semantic_type ();
                    ^

Using a local typedef, for some reaon, result in clang complaining
about a useless local typedef.  Since anyway we don't want to keep on
using YYSTYPE and YYLTYPE, it is time to introduce proper typedefs to
reach these guys.  And to be slightly in advance of the other
skeletons: use value_type, not semantic_type.  This is much more
consistent with our use of the (kind, value, location) triplet.

* data/skeletons/glr2.cc (glr_state::value_type)
(glr_state::location_type): New.
(glr_state::~glr_state): Use value_type to name the dtor.
2020-12-20 18:46:17 +01:00
Akim Demaille 0a82316e54 glr2.cc: example: use objects (not pointers) to represent the AST
Currently we are using pointers.  The whole point of
glr2.cc (vs. glr.cc) is precisely to allow genuine C++ objects to be
semantic values.  Let's make that work.

* data/skeletons/glr2.cc (glr_state::glr_state): Be sure to initialize
yysval.
(glr_state): Add copy-ctor, assignment and dtor.
(glr_state::copyFrom): Be sure to initialize the destination if it was
not.
(glr_state::~glr_state): Destroy the semantic value.
* examples/c++/glr/ast.hh: Rewrite so that we use genuine objects,
rather than a traditional OOP hierarchy that requires to deal with
pointers.
With help from Bruno Belanyi <[email protected]>.
* examples/c++/glr/c++-types.yy: Remove memory management.
Use true objects.
(main): Don't reach yydebug directly.

* examples/c++/glr/local.mk: We need C++11.
2020-12-20 18:41:42 +01:00
Akim Demaille 611348e67b glr2.cc: more checks
* data/skeletons/glr2.cc: Clarify use of magic numbers.
(glr_stack_item::getState): Check the returned state.
2020-12-20 15:56:22 +01:00
Akim Demaille fe0102d4d5 glr2.cc: fix GLR stack expansion
When expanding the GLR stack, none of the pointers were updated to
reflect the new location of the displaced objects.

This fixes

    748: Incorrect lookahead during nondeterministic GLR: glr2.cc

* data/skeletons/glr2.cc (yyexpandGLRStack): Update the split point
and the stack tops.
(reduceToOneStack): Factor a bit.
2020-12-20 14:54:47 +01:00
Akim Demaille 718cb1ab38 glr2.cc: factor the computation of the accessing symbol
* data/skeletons/glr2.cc (yy_accessing_symbol): New, as in glr.c.
Use it.
2020-12-20 14:54:46 +01:00
Akim Demaille 08f657f4a4 glr2.cc: fix calling conventions for yyexpandGLRStackIfNeeded
This test fails:

748: Incorrect lookahead during nondeterministic GLR: glr2.cc

It consumes lots of stack space, so at some point we need to expand
it.  Because of Boolean logic mistakes, we then claim
memory-exhausted (first error).  Hence we jump to cleaning the
stack (popall_), calling all the destructors, and at some point we
crash with heap-use-after-free (second error).

This commit fixes the first error.  Unfortunately, even though we now
do expand the stack, we crash again with (another)
heap-use-after-free, not addressed here.

Eventually, we should make sure popall_() properly works.

* data/skeletons/glr2.cc (yyexpandGLRStackIfNeeded): Return true iff
success (i.e., memory not exhausted).
2020-12-20 14:54:46 +01:00
Akim Demaille 7292ed6e64 glr2.cc: example: use streams and accept arguments
From a debugger, it is easier to pass a file name than working on
stdin.

* examples/c++/glr/c++-types.yy: Reduce scopes.
Avoid YYSTYPE/YYLTYPE: use the C++ types.
(input, process): New.
(main): Use them.
2020-12-20 14:54:46 +01:00
Akim Demaille 3f473dd2d7 glr: formatting changes
* data/skeletons/glr.c: Formatting changes.
* data/skeletons/glr2.cc: Ditto.
(glr_state_set::INITIAL_NUMBER_STATES): Remove, unused (and useless:
let std::vector deal with that).
2020-12-20 14:54:46 +01:00
Akim Demaille 03d33fd3a4 skeletons: better comments for some tables
And also, remove the incorrect indentation of these comments:

    -  /* YYR2[YYN] -- Number of symbols on the right hand side of rule YYN.  */
    +/* YYR2[RULE-NUM] -- Number of symbols on the right-hand side of rule RULE-NUM.  */
     static const yytype_int8 yyr2[] =
     {
            0,     2,     4,     0,     2,     1,     1,     1,     3,     2,

I don't remember why this indentation was added (in
0991e29b75), but it seems wrong,
at least for yacc.c.  I suspect this was done with lalr1.cc (where
this is embeded in the class definition, so it should be indented),
but today lalr1.cc uses other routines to output these comments.

* data/skeletons/bison.m4 (b4_integral_parser_tables_map): Improve the
wording of the comments of some tables.
* data/skeletons/c.m4 (b4_integral_parser_table_define): Remove
indentation.
2020-12-20 14:54:46 +01:00
Akim Demaille 0a6c2e6400 glr2.cc: fix glr_stack_item::setState
A glr_stack_item has "raw" memory to store either a glr_state or a
semantic_option.  glr_stack_item::setState stores a state using a copy
assignment.  However, this is more like a construction: we are
starting from "raw" memory, so use the placement new operator instead.
While it probably makes no difference when parse.assert is disabled,
it does make one when it is: the constructor properly initialize the
magic number, the assignment does not.  So without these changes, the
next commit (which stores genuine objects in semantic values) fails
tests 712 and 730 because of incorrect magic numbers.

* data/skeletons/glr2.cc (glr_stack_item::setState): Build the state,
don't just copy it.
2020-12-19 07:29:37 +01:00
Akim Demaille 640b1313d7 glr2.cc: more self checks
* data/skeletons/glr2.cc: here.
2020-12-19 07:29:37 +01:00
Akim Demaille 66706a7c19 glr2.cc: style: s/Type/Kind/g
* data/skeletons/glr2.cc (YY_SYMBOL_PRINT): Use Kind, not Type.
As in the other skeletons.
2020-12-19 07:29:37 +01:00
Akim Demaille 80664353b2 glr2.cc: example: style: add missing copyright headers
* examples/c++/glr/ast.hh, examples/c++/glr/c++-types.yy: here.
* examples/c++/glr/local.mk: Fix distribution of ast.hh.
2020-12-19 07:29:30 +01:00
Akim Demaille d6fbeb2798 glr2.cc: example: address Clang warnings
ast.hh:24:7: error: 'Node' has no out-of-line virtual method definitions; its vtable will be emitted in every translation unit [-Werror,-Wweak-vtables]
    class Node
          ^
    ast.hh:57:7: error: 'Nterm' has no out-of-line virtual method definitions; its vtable will be emitted in every translation unit [-Werror,-Wweak-vtables]
    class Nterm : public Node
          ^
    ast.hh:102:7: error: 'Term' has no out-of-line virtual method definitions; its vtable will be emitted in every translation unit [-Werror,-Wweak-vtables]
    class Term : public Node
          ^

* examples/c++/glr/ast.hh: Define the destructors out of the class
definition.
This does not change anything, it is still in the header, but that
does pacify clang.
2020-12-19 07:29:29 +01:00
Akim Demaille b33817f8bb glr: tests: add support for the YYDEBUG envvar
When debugging these parsers, we really need debug traces.
Enable them, and bind them to $YYDEBUG.

* tests/glr-regression.at: Support the YYDEBUG envvar.
As a consequence, now that syntactic ambiguities are reported, adjust
the expected output.
(No users destructors if stack 0 deleted): Don't return 0 on memory
exhaustion, really return the parser's status, and adust expectations.
2020-12-16 07:38:59 +01:00
Akim Demaille c97dbc46af glr.c: comment changes
* data/skeletons/glr.c (yycompressStack): Reduce scope, and import some
nice comments from glr2.cc.
2020-12-14 06:33:22 +01:00
Akim Demaille b2d35f5cb8 glr2.cc: make the example more C++
Currently the example really looks like C.  Instead of a union of
structs to implement the AST, use a hierarchy.  It would be nice to
feature a C++17 version with std variants.

* examples/c++/glr/c++-types.yy (Node, free_node, new_nterm)
(new_term): Move into...
* examples/c++/glr/ast.hh: here, a proper C++ hierarchy.
2020-12-14 06:33:22 +01:00
Akim Demaille 855d46678a glr2.cc: make yyparse a member function
Amusingly enough, glr2.cc still had its core function, yyparse, being
a free function instead of a member function.

* data/skeletons/glr2.cc (yyparse): Remove this free function called
from yyparser::parse.  Inline its body into...
(yyparser::parse): this member function.
This requires moving a bit the yychar, etc. macros.
Access to token can be simplified (the
b4_namespace_ref::b4_parser_class prefix is no longer needed).
2020-12-14 06:33:22 +01:00
Akim Demaille 178a033e8b glr2.cc: being pure is not an option
Remove the useless conditional b4_pure_if: the skeleton is, of course,
pure (no global variables).  Make glr2.cc intrinsically pure.

* data/skeletons/glr2.cc (b4_pure_if): Remove definition and uses.
(b4_lex): New.
Stolen from lalr1.cc to avoid needing to use the one from c.m4.
2020-12-14 06:33:22 +01:00
Akim Demaille c8006f4637 glr2.cc: fix yycompressStack
Currently, yycompressStack expects the free items to be states only.
That's not the case.

Fixes 712 and 730 pass.  748 still fails, but later and
differently (heap-use-after-free).

* data/skeletons/glr2.cc (glr_stack_item::setState): New.
(glr_stack_item::yycompressStack): Use it.
* tests/glr-regression.at: Adjust.
2020-12-14 06:33:22 +01:00
Akim Demaille 5b65b3d543 glr2.cc: fix pointer arithmethics
A glr_state keeps tracks of its predecessor using an offset relative
to itself (i.e., pointer subtraction).  Unfortunately we sometimes
have to compute offsets for pointers that live in different
containers, in particular in yyfillin.  In that case there is no
reason for the distance between the two objects to be a multiple of
the object size (0x40 on my machine), and the resulting ptrdiff_t may
be "wrong", i.e., it does allow to recover one from the other.  We
cannot use "typed" pointer arithmetics here, the Euclidean division
has it wrong.  So use "plain" char* pointers.

Fixes 718 (Duplicate representation of merged trees: glr2.cc) and
examples/c++/glr/c++-types.

Still XFAIL:

    712: Improper handling of embedded actions and dollar(-N) in GLR parsers: glr2.cc
    730: Incorrectly initialized location for empty right-hand side in GLR: glr2.cc
    748: Incorrect lookahead during nondeterministic GLR: glr2.cc

* data/skeletons/glr2.cc (glr_state::as_pointer_): New.
(glr_state::pred): Use it.
* examples/c++/glr/c++-types.test: The test passes.
* tests/glr-regression.at (Duplicate representation of merged trees:
glr2.cc): Passes.
2020-12-14 06:33:21 +01:00
Akim Demaille 2b52bd1644 glr2.cc: style fixes
* data/skeletons/glr2.cc: Formatting changes.
2020-12-14 06:33:12 +01:00
Akim Demaille 9ee51ece65 glr2.cc: add sanity check in glr_state
The use of YY_IGNORE_NULL_DEREFERENCE_BEGIN/END in `check_` is to
please GCC 10:

    glr-regr8.cc: In member function 'YYRESULTTAG glr_stack::yyresolveValue(glr_state&)':
    glr-regr8.cc:1433:21: error: potential null pointer dereference [-Werror=null-dereference]
     1433 |     YYASSERT (this->magic_ == MAGIC);
          |               ~~~~~~^~~~~~
    glr-regr8.cc:905:40: note: in definition of macro 'YYASSERT'
      905 | # define YYASSERT(Condition) ((void) ((Condition) || (abort (), 0)))
          |                                        ^~~~~~~~~

* data/skeletons/glr2.cc (glr_state::check_): New.
Use it in the member functions.
2020-12-13 06:59:04 +01:00
Akim Demaille 2313f891bd glr2.cc: add sanity checks in glr_stack_item
We obviously have broken pointer arithmetics that hands us
glr_stack_items that are not glr_stack_items.  Have a simple check for
this, to have earlier failures.

* data/skeletons/glr2.cc (glr_stack_item::check_): New.
Use it.
(glr_stack_item::contents): Avoid the useless struct.
Fix minor stylistic issues.
2020-12-13 06:31:41 +01:00
Akim Demaille 42fe808292 glr2.cc: run the glr-regression tests
When installed on master as of 2020-12-05 (on top of "glr2.cc: fix
when the stack is not expandable", almost all the GLR regression tests
fail (with a SEGV):

    709: Badly Collapsed GLR States: glr2.cc             FAILED (glr-regression.at:130)
    712: Improper handling of embedded actions and dollar(-N) in GLR parsers: glr2.cc FAILED (glr-regression.at:275)
    715: Improper merging of GLR delayed action sets: glr2.cc FAILED (glr-regression.at:404)
    718: Duplicate representation of merged trees: glr2.cc FAILED (glr-regression.at:502)
    721: User destructor for unresolved GLR semantic value: glr2.cc FAILED (glr-regression.at:566)
    724: User destructor after an error during a split parse: glr2.cc FAILED (glr-regression.at:624)
    727: Duplicated user destructor for lookahead: glr2.cc FAILED (glr-regression.at:724)
    730: Incorrectly initialized location for empty right-hand side in GLR: glr2.cc FAILED (glr-regression.at:823)
    733: No users destructors if stack 0 deleted: glr2.cc FAILED (glr-regression.at:911)
    736: Corrupted semantic options if user action cuts parse: glr2.cc FAILED (glr-regression.at:974)
    739: Undesirable destructors if user action cuts parse: glr2.cc FAILED (glr-regression.at:1042)
    742: Leaked semantic values if user action cuts parse: glr2.cc FAILED (glr-regression.at:1173)
    748: Incorrect lookahead during nondeterministic GLR: glr2.cc FAILED (glr-regression.at:1546)
    751: Leaked semantic values when reporting ambiguity: glr2.cc FAILED (glr-regression.at:1639)
    754: Leaked lookahead after nondeterministic parse syntax error: glr2.cc FAILED (glr-regression.at:1710)
    757: Uninitialized location when reporting ambiguity: glr2.cc FAILED (glr-regression.at:1794)
    766: Predicates: glr2.cc                             FAILED (glr-regression.at:2045)

These pass:

    745: Incorrect lookahead during deterministic GLR: glr2.cc ok
    760: Missed %merge type warnings when LHS type is declared later: glr2.cc ok
    763: Ambiguity reports: glr2.cc ok

With Valentin Tolmer's "glr2.cc: Fix memory corruption bug" commit,
these test fail "gracefully":

    712: Improper handling of embedded actions and dollar(-N) in GLR parsers: glr2.cc FAILED (glr-regression.at:268)
    730: Incorrectly initialized location for empty right-hand side in GLR: glr2.cc FAILED (glr-regression.at:816)
    748: Incorrect lookahead during nondeterministic GLR: glr2.cc FAILED (glr-regression.at:1539)

And these do not end:

    709: Badly Collapsed GLR States: glr2.cc             FAILED (glr-regression.at:123)
    715: Improper merging of GLR delayed action sets: glr2.cc FAILED (glr-regression.at:397)
    718: Duplicate representation of merged trees: glr2.cc FAILED (glr-regression.at:495)
    751: Leaked semantic values when reporting ambiguity: glr2.cc FAILED (glr-regression.at:1632)

With "tests: glr2.cc: run the glr-regression tests", none loop, and
709, 715, and 751 pass.  Only 718 still fails.

* tests/glr-regression.at: Run all the tests with glr2.cc.
* tests/local.at (AT_GLR2_CC_IF): New.
2020-12-06 15:11:33 +01:00
Akim Demaille 4beefee4bf glr2.cc: use the same format for traces as glr.c
* data/skeletons/glr2.cc: here.
This allows to share the same expected output.
2020-12-06 14:02:38 +01:00
Akim Demaille 3301849f0f glr2.cc: add support for parse.assert
* data/skeletons/glr2.cc: Fake support of parse.assert, so that the
tests can use it without failing.
2020-12-06 14:02:38 +01:00
Akim Demaille 349ea900f5 glr2.cc: fix yyresolveValue
When "tests: glr2.cc: run the glr-regression tests" tests are run,
before this commit the following tests used to loop endlessly:

    709: Badly Collapsed GLR States: glr2.cc             FAILED (glr-regression.at:123)
    715: Improper merging of GLR delayed action sets: glr2.cc FAILED (glr-regression.at:397)
    718: Duplicate representation of merged trees: glr2.cc FAILED (glr-regression.at:495)
    751: Leaked semantic values when reporting ambiguity: glr2.cc FAILED (glr-regression.at:1632)

After this commit, no test loops and 709, 715, and 751 pass.  Only 718
still fails.

* data/skeletons/glr2.cc (yyresolveValue): Add missing incrementation
of the iteration variable.
2020-12-06 14:02:38 +01:00
Akim Demaille e72eda7aee glr2.cc: turn some pointers into references
* data/skeletons/glr2.cc: Prefer references to pointers.
Add a few more const.
2020-12-06 14:02:38 +01:00
Akim Demaille 12b5924939 glr2.cc: fix when the stack is not expandable
* data/skeletons/glr2.cc (yyexpandGLRStackIfNeeded): Fix the
implementation when !YYSTACKEXPANDABLE.
2020-12-06 13:54:45 +01:00
Akim Demaille d4188398f1 glr.c: fix line numbers in logs
* data/skeletons/glr.c (yyglrReduce): Fix line numbers.
* tests/glr-regression.at: Fix expectations.
2020-12-06 13:54:45 +01:00
Akim Demaille 8ab625e517 tests: glr: run the glr regression tests with glr.cc
* tests/glr-regression.at: Adjust the tests to be more independent of
the language, and run them with glr.cc.
Some tests relied on yychar, yylval and yylloc being global variables:
pass arguments instead.
2020-12-05 12:39:59 +01:00
Akim Demaille edf6aa7d3b tests: glr: prepare for more languages
* tests/glr-regression.at: Wrap each test in an AT_TEST.
Call it with glr.c.
2020-12-05 12:39:59 +01:00
Akim Demaille 4aec17af93 tests: glr: use AT_FULL_COMPILE
* tests/glr-regression.at: Instead of using AT_BISON_CHECK and
AT_COMPILE, use AT_FULL_COMPILE.  This is shorter, and makes it easier
to add support for other programming languages.
2020-12-05 11:22:20 +01:00
Akim Demaille c98b8856e6 tests: glr: prefer directives to warnings
* tests/glr-regression.at: Use %expect and %expect-rr in the grammar
files, rather than accepting diagnostics.
This will make it easier to support other programming languages.
2020-12-05 11:22:20 +01:00
Akim Demaille 4ec49a8585 tests: factor the access to token kinds
* tests/local.at (AT_BISON_OPTION_PUSHDEFS): Define AT_TOKEN.
(AT_BISON_OPTION_POPDEFS): Undefine it.
* tests/actions.at, tests/c++.at, tests/calc.at: Use AT_TOKEN.
2020-12-05 11:22:20 +01:00
Akim Demaille 627d275a3a tests: formatting changes
* tests/local.at: here.
2020-12-05 11:22:20 +01:00
Akim Demaille 84a84560c3 glr.cc: don't "leak" yyparse
When using glr.cc, the C function yyparse is an internal detail that
should not be exposed.  Users might call it by accident (I did).

* data/skeletons/glr.c (yyparse): When used for glr.cc, rename as yy_parse_impl.
* data/skeletons/glr.cc: Adjust.
2020-12-05 07:36:01 +01:00
Akim Demaille 0e78a9028e portability: beware of GCC 4.6
src/reader.c: In function 'grammar_start_symbols_add':
    src/reader.c:67:24: error: declaration of 'dup' shadows a global declaration [-Werror=shadow]

* src/reader.c (grammar_start_symbols_add): Rename dup as dupl.
2020-12-03 19:46:20 +01:00
Akim Demaille 24233748ec tables: avoid warnings and save bits
The yydefgoto table uses -1 as an invalid for an impossible case (we
never use yydefgoto[0], since it corresponds to the reduction to
$accept, which never happens).  Since yydefgoto is a table of state
numbers, this -1 forces a signed type uselessly, which (1) might
trigger compiler warnings when storing a value from yydefgoto into a
state number (nonnegative), and (2) wastes bits which might result in
using a int16 where a uint8 suffices.

Reported by Jot Dot <[email protected]>.
https://lists.gnu.org/r/bug-bison/2020-11/msg00027.html

* src/tables.c (default_goto): Use 0 rather than -1 as invalid value.
* tests/regression.at: Adjust.
2020-12-03 06:21:53 +01:00
Akim Demaille 9840e5b621 c++: use noexcept where appropriate
Reported by Don Macpherson.
https://github.com/akimd/bison/issues/63
https://github.com/akimd/bison/issues/64

* data/skeletons/c++.m4, data/skeletons/lalr1.cc: here.
2020-12-03 06:19:17 +01:00
Akim Demaille 8eede447db gnulib: update 2020-11-30 16:48:04 +01:00
Akim Demaille 5b19f91ccf multistart: check duplicates
* src/symlist.h, src/symlist.c (symbol_list_find_symbol)
(symbol_list_last): New.
(symbol_list_append): Use symbol_list_last.
* src/reader.c (grammar_start_symbols_add): Check and discard duplicates.
* tests/input.at (Duplicate %start symbol): New.
* tests/reduce.at (Bad start symbols): Add the multistart keyword.
2020-11-30 16:48:03 +01:00
Akim Demaille 7fe9205b9f style: change the format of a debugging function
* src/symlist.c (symbol_list_syms_print): Use braces to make traces
easier to read.
2020-11-22 16:01:05 +01:00
Akim Demaille d798851e48 style: rename grammar_start_symbols_set as grammar_start_symbols_add
* src/reader.h, src/reader.c (grammar_start_symbols_set): Rename as...
(grammar_start_symbols_add): this.
Adjust dependencies.
2020-11-22 11:18:20 +01:00
Akim Demaille 5af04b99dd TODO: update 2020-11-22 09:57:17 +01:00
Akim Demaille 38cdb2aba2 multistart: also use the api.prefix in the implementation
We were declaring foo_parse_expr but implementing yyparse_expr.

* data/skeletons/yacc.c (_b4_define_sub_yyparse): Use api.prefix for
the parse function name.
2020-11-21 14:57:29 +01:00