The following changes (change numbers refer to perforce) were made from version 3.1.1 to 3.1.2 Runtime ------- Change 5641 on 2009/02/20 by jimi@jimi.jimi.antlr3 Release version 3.1.2 of the ANTLR C runtime. Updated documents and release notes will have to follow later. Change 5639 on 2009/02/20 by jimi@jimi.jimi.antlr3 Fixed: ANTLR-356 Ensure that code generation for C++ does not require casts Change 5577 on 2009/02/12 by jimi@jimi.jimi.antlr3 C Runtime - Bug fixes. o Having moved to use an extract directly from a vector for returning tokens, it exposed a bug whereby the EOF boudary calculation in tokLT was incorrectly checking > rather than >=. o Changing to API initialization of tokens rather than memcmp() incorrectly forgot to set teh input stream pointer for the manufactured tokens in the token factory; o Rewrite streams for rewriting tree parsers did not check whether the rewrite stream was ever assigned before trying to free it, it is now in line with the ordinary parser code. Change 5576 on 2009/02/11 by jimi@jimi.jimi.antlr3 C Runtime: Ensure that when we manufacture a new token for a missing token, that the user suplied custom information (if any) is copied from the current token. Change 5575 on 2009/02/08 by jimi@jimi.jimi.antlr3 C Runtime - Vastly improve the reuse of allocated memory for nodes in tree rewriting. A problem for all targets at the moment si that the rewrite logic generated by ANTLR makes no attempt to reuse any resources, it merely gurantees that the tree shape at the end is correct. To some extent this is mitigated by the garbage collection systems of Java and .Net, even thoguh it is still an overhead to keep creating so many modes. This change implements the first of two C runtime changes that make best efforst to track when a node has become orphaned and will never be reused, based on inherent knowledge of the rewrite logic (which in the long term is not a great soloution). Much of the rewrite logic consists of creating a niilnode into which child nodes are appended. At: rulePost processing time; when a rewrite stream is closed; and when becomeRoot is called, there are many situations where the root of the tree that will be manipulted, or is finished with (in the case of rewrtie streams), where the nilNode was just a temporary creation for the sake of the rewrite itself. In these cases we can see that the nilNode would just be left ot rot in the node factory that tracks all the tree nodes. Rather than leave these in the factory to rot, we now keep a resuse stck and always reuse any node on this stack before claimin a new node from the factory pool. This single change alone reduces memory usage in the test case (20,604 line C program and a GNU C parser) from nearly a GB, to 276MB. This is still way more memory than we shoudl need to do this operation, even on such a large input file, but the reduction results in a huge performance increase and greatly reduced system time spent on allocations. After this optimizatoin, comparison with gcc yeilds: time gcc -S a.c a.c:1026: warning: conflicting types for built-in function ‘vsprintf’ a.c:1030: warning: conflicting types for built-in function ‘vsnprintf’ a.c:1041: warning: conflicting types for built-in function ‘vsscanf’ 0.21user 0.01system 0:00.22elapsed 97%CPU (0avgtext+0avgdata 0maxresident)k 0inputs+240outputs (0major+8345minor)pagefaults 0swaps and time ./jimi Reading a.c 0.28user 0.11system 0:00.39elapsed 98%CPU (0avgtext+0avgdata 0maxresident)k 0inputs+0outputs (0major+66609minor)pagefaults 0swaps And we can now interpolate the fact that the only major differnce is now the huge disparity in memory allocations. A future optimization of vector pooling, to sepate node resue from vector reuse, currently looks promising for further reuse of memory. Finally, a static analysis of the rewrte code, plus a realtime analysis of the heap at runtime, may well give us a reasonable memory usage pattern. In reality though, it is the generated rewrite logic that must becom optional at not continuously rewriting things that it need not, as it ascends the rule chain. Change 5563 on 2009/01/28 by jimi@jimi.jimi.antlr3 Allow rewrite streams to use the base adaptors vector factory and not try to malloc new vectors themselves. Change 5562 on 2009/01/28 by jimi@jimi.jimi.antlr3 Don't use CALLOC to allocate tree pools, use malloc as there is no need for calloc. Change 5561 on 2009/01/28 by jimi@jimi.jimi.antlr3 Prevent warnigsn about retval.stop not being initialized when a rule returns eraly because it is in backtracking mode Change 5558 on 2009/01/28 by jimi@jimi.jimi.antlr3 Lots of optimizations (though the next one to be checked in is the huge win) for AST building and vector factories. A large part of tree rewriting was the creation of vectors to hold AST nodes. Although I had created a vector factory, for some reason I never got around to creating a proper one, that pre-allocated the vectors in chunks and so on. I guess I just forgot to. Hence a big win here is prevention of calling malloc lots and lots of times to create vectors. A second inprovement was to change teh vector definition such that it holds a certain number of elements wihtin the vector structure itself, rather than malloc and freeing these. Currently this is set to 8, but may increase. For AST construction, this is generally a big win because AST nodes don't often have many individual children unless there has not been any shaping going on in the parser. But if you are not shaping, then you don't really need a tree. Other perforamnce inprovements here include not calling functions indirectly within token stream and common token stream. Hence tokens are claimed directly from the vectors. Users can override these funcitons of course and all this means is that if you override tokenstreams then you pretty much have to provide all the mehtods, but then I think you woudl have to anyway (and I don't know of anyone that has wanted to do this as you can carry your own structure around with the tokens anyway and that is much easier). Change 5555 on 2009/01/26 by jimi@jimi.jimi.antlr3 Fixed: ANTLR-288 Correct the interpretation of the skip token such that channel, start index, char pos in lie, start line and text are correctly reset to the start of the new token when the one that we just traversed was marked as being skipped. This correctly excludes the text that was matched as part of the SKIP()ed token from the next token in the token stream and so has the side effect that asking for $text of a rule no longer includes the text that shuodl be skipped, but DOES include the text of tokens that were merely placed off the default channel. Change 5551 on 2009/01/25 by jimi@jimi.jimi.antlr3 Fixed: ANTLR-287 Most of the source files did not include the BSD license. THis might not be that big a deal given that I don't care what people do with it other than take my name off it, but having the license reproduced everywhere at least makes things perfectly clear. Hence this mass change of sources and templates to include the license. Change 5550 on 2009/01/25 by jimi@jimi.jimi.antlr3 Fixed: ANTLR-365 Ensure that as soon as we known about an input stream on the lexer that we borrow its string factroy adn use it in our EOF token in case anyone tries to make it a string, such as in error messages for instance. Change 5548 on 2009/01/25 by jimi@jimi.jimi.antlr3 Fixed: ANTLR-363 At some point the Java runtime default changed from discarding offchannel tokens to preserving them. The fix is to make the C runtime also default to preserving off-channel tokens. Change 5544 on 2009/01/24 by jimi@jimi.jimi.antlr3 Fixed: ANTLR-360 Ensure that the fillBuffer funtiion does not call any methods that require the cached buffer size to be recorded before we have actually recorded it. Change 5543 on 2009/01/24 by jimi@jimi.jimi.antlr3 Fixed: ANTLR-362 Some users have started using string factories themselves and exposed a flaw in the destroy method, that is intended to remove a strng htat was created by the factory and is no longer needed. The string was correctly removed from the vector that tracks them but after the first one, all the remaining strings are then numbered incorrectly. Hence the destroy method has been recoded to reindex the strings in the factory after one is removed and everythig is once more hunky dory. User suggested fix rejected. Change 5542 on 2009/01/24 by jimi@jimi.jimi.antlr3 Fixed ANTLR-366 The recognizer state now ensures that all fields are set to NULL upon creation and the reset does not overwrite the tokenname array Change 5527 on 2009/01/15 by jimi@jimi.jimi.antlr3 Add the C runtime for 3.1.2 beta2 to perforce Change 5526 on 2009/01/15 by jimi@jimi.jimivista.antlr3 Correctly define the MEMMOVE macro which was inadvertently left to be memcpy. Change 5503 on 2008/12/12 by jimi@jimi.jimi.antlr3 Change C runtime release number to 3.1.2 beta Change 5473 on 2008/12/01 by jimi@jimi.jimivista.antlr3 Fixed: ANTLR-350 - C runtime use of memcpy Prior change to use memcpy instead of memmove in all cases missed the fact that the string factory can be in a situation where overlaps occur. We now have ANTLR3_MEMCPY and ANTLR3_MEMMOVE and use the two appropriately. Change 5471 on 2008/12/01 by jimi@jimi.jimivista.antlr3 Fixed ANTLR-361 - Ensure that ANTLR3_BOOLEAN is typedef'ed correctly when building for MingW Templates --------- Change 5637 on 2009/02/20 by jimi@jimi.jimi.antlr3 C rtunime - make sure that ADAPTOR results are cast to the tree type on a rewrite Change 5620 on 2009/02/18 by jimi@jimi.jimi.antlr3 Rename/Move: From: //depot/code/antlr/main/src/org/antlr/codegen/templates/... To: //depot/code/antlr/main/src/main/resources/org/antlr/codegen/templates/... Relocate the code generating templates to exist in the directory set that maven expects. When checking in your templates, you may find it easiest to make a copy of what you have, revert the change in perforce, then just check out the template in the new location, and copy the changes back over. Nobody has oore than two files open at the moment. Change 5578 on 2009/02/12 by jimi@jimi.jimi.antlr3 Correct the string template escape sequences for generating scope code in the C templates. Change 5577 on 2009/02/12 by jimi@jimi.jimi.antlr3 C Runtime - Bug fixes. o Having moved to use an extract directly from a vector for returning tokens, it exposed a bug whereby the EOF boudary calculation in tokLT was incorrectly checking > rather than >=. o Changing to API initialization of tokens rather than memcmp() incorrectly forgot to set teh input stream pointer for the manufactured tokens in the token factory; o Rewrite streams for rewriting tree parsers did not check whether the rewrite stream was ever assigned before trying to free it, it is now in line with the ordinary parser code. Change 5567 on 2009/01/29 by jimi@jimi.jimi.antlr3 C Runtime - Further Optimizations Within grammars that used scopes and were intended to parse large inputs with many rule nests, the creation anf deletion of the scopes themselves became significant. Careful analysis shows that for most grammars, while a parse could create and delete 20,000 scopes, the maxium depth of any scope was only 8. This change therefore changes the scope implementation so that it does not free scope memory when it is popped but just tracks it in a C runtime stack, eventually freeing it when the stack is freed. This change caused the allocation of only 12 scope structures instead of 20,000 for the extreme example case. This change means that scope users must be carefule (as ever in C) to initializae their scope elements correctly as: 1) If not you may inherit values from a prior use of the scope structure; 2) SCope structure are now allocated with malloc and not calloc; Also, when using a custom free function to clean a scope when it is popped, it is probably a good idea to set any free'd pointers to NULL (this is generally good C programmig practice in any case) Change 5566 on 2009/01/29 by jimi@jimi.jimi.antlr3 Remove redundant BACKTRACK checking so that MSVC9 does not get confused about possibly uninitialized variables Change 5565 on 2009/01/28 by jimi@jimi.jimi.antlr3 Use malloc rather than calloc to allocate memory for new scopes. Note that this means users will have to be careful to initialize any values in their scopes that they expect to be 0 or NULL and I must document this. Change 5564 on 2009/01/28 by jimi@jimi.jimi.antlr3 Use malloc rather than calloc for copying list lable tokens for rewrites. Change 5561 on 2009/01/28 by jimi@jimi.jimi.antlr3 Prevent warnigsn about retval.stop not being initialized when a rule returns eraly because it is in backtracking mode Change 5560 on 2009/01/28 by jimi@jimi.jimi.antlr3 Add a NULL check before freeing rewrite streams used in AST rewrites rather than auto-rewrites. While the NULL check is redundant as the free cannot be called unless it is assigned, Visual Studio C 2008 gets it wrong and thinks that there is a PATH than can arrive at the free wihtout it being assigned and that is too annoying to ignore. Change 5559 on 2009/01/28 by jimi@jimi.jimi.antlr3 C target Tree rewrite optimization There is only one optimization in this change, but it is a huge one. The code generation templates were set up so that at the start of a rule, any rewrite streams mentioned in the rule wer pre-created. However, this is a massive overhead for rules where only one or two of the streams are actually used, as we create them then free them without ever using them. This was copied from the Java templates basically. This caused literally millions of extra calls and vector allocations in the case of the GNU C parser given to me for testing with a 20,000 line program. After this change, the following comparison is avaiable against the gcc compiler: Before (different machines here so use the relative difference for comparison): gcc: real 0m0.425s user 0m0.384s sys 0m0.036s ANTLR C real 0m1.958s user 0m1.284s sys 0m0.656s After the previous optimizations for vector pooling via a factory, plus this huge win in removing redundant code, we have the following (different machine to the one above): gcc: 0.21user 0.01system 0:00.23elapsed 99%CPU (0avgtext+0avgdata 0maxresident)k 0inputs+328outputs (0major+9922minor)pagefaults 0swaps ANTLR C: 0.37user 0.26system 0:00.64elapsed 99%CPU (0avgtext+0avgdata 0maxresident)k 0inputs+0outputs (0major+130944minor)pagefaults 0swaps The extra system time coming from the fact that although the tree rewriting is now optimal in terms of not allocating things it does not need, there is still a lot more overhead in a parser that is generated for generic use, including much more use of structures for tokens and extra copying and so on. I will continue to work on improviing things where I can, but the next big improvement will come from Ter's optimization of the actual code structures we generate including not doing things with rewrite streams that we do not need to do at all. The second machine I used is about twice as fast CPU wise as the system that was used originally by the user that asked about this performance. Change 5558 on 2009/01/28 by jimi@jimi.jimi.antlr3 Lots of optimizations (though the next one to be checked in is the huge win) for AST building and vector factories. A large part of tree rewriting was the creation of vectors to hold AST nodes. Although I had created a vector factory, for some reason I never got around to creating a proper one, that pre-allocated the vectors in chunks and so on. I guess I just forgot to. Hence a big win here is prevention of calling malloc lots and lots of times to create vectors. A second inprovement was to change teh vector definition such that it holds a certain number of elements wihtin the vector structure itself, rather than malloc and freeing these. Currently this is set to 8, but may increase. For AST construction, this is generally a big win because AST nodes don't often have many individual children unless there has not been any shaping going on in the parser. But if you are not shaping, then you don't really need a tree. Other perforamnce inprovements here include not calling functions indirectly within token stream and common token stream. Hence tokens are claimed directly from the vectors. Users can override these funcitons of course and all this means is that if you override tokenstreams then you pretty much have to provide all the mehtods, but then I think you woudl have to anyway (and I don't know of anyone that has wanted to do this as you can carry your own structure around with the tokens anyway and that is much easier). Change 5554 on 2009/01/26 by jimi@jimi.jimi.antlr3 Fixed: ANTLR-379 For some reason in the past, the ruleMemozation() template had required that the name parameter be set to the rule name. This does not seem to be a requirement any more. The name=xxx override when invoking the template was causing all the scope names derived when cleaning up in memoization to be called after the rule name, which was not correct. Howver, this only affected the output when in output=AST mode. This template invocation is now corrected. Change 5553 on 2009/01/26 by jimi@jimi.jimi.antlr3 Fixed: ANTLR-330 Managed to get the one rule that could not see the ASTLabelType to call back in to the super template C.stg and ask it to construct hte name. I am not 100% sure that this fixes all cases, but I cannot find any that fail. PLease let me know if you find any exampoles of being unable to default the ASTLabelType option in the C target. Change 5552 on 2009/01/25 by jimi@jimi.jimi.antlr3 Progress: ANTLR-327 Fix debug code generation templates when output=AST such that code can at least be generated and I can debug the output code correctly. Note that this checkin does not implement the debugging requirements for tree generating parsers. Change 5551 on 2009/01/25 by jimi@jimi.jimi.antlr3 Fixed: ANTLR-287 Most of the source files did not include the BSD license. THis might not be that big a deal given that I don't care what people do with it other than take my name off it, but having the license reproduced everywhere at least makes things perfectly clear. Hence this mass change of sources and templates to include the license. Change 5549 on 2009/01/25 by jimi@jimi.jimi.antlr3 Fixed: ANTLR-354 Using 0.0D as the default initialize value for a double caused VS 2003 C compiler to bomb out. There seesm to be no reason other than force of habit to set this to 0.0D so I have dropped the D so that older compilers do not complain. Change 5547 on 2009/01/25 by jimi@jimi.jimi.antlr3 Fixed: ANTLR-282 All references are now unadorned with any type of NULL check for the following reasons: 1) A NULL reference means that there is a problem with the grammar and we need the program to fail immediately so that the programmer can work out where the problem occured; 2) Most of the time, the only sensible value that can be returned is NULL or 0 which obviates the NULL check in the first place; 3) If we replace a NULL reference with some value such as 0, then the program may blithely continue but just do something logically wrong, which will be very difficult for the grammar programmer to detect and correct. Change 5545 on 2009/01/24 by jimi@jimi.jimi.antlr3 Fixed: ANTLR-357 The bug report was correct in that the types of references to things like $start were being incorrectly cast as they wer not changed from Java style casts (and the casts are unneccessary). this is now fixed and references are referencing the correct, uncast, types. However, the bug report was wrong in that the reference in the bok to $start.pos will only work for Java and really, it is incorrect in the book because it shoudl not access the .pos member directly but shudl be using $start.getCharPositionInLine(). Because there is no access qualification in C, one could use $start.charPosition, however really this should be $start->getCharPositionInLine($start); Change 5541 on 2009/01/24 by jimi@jimi.jimi.antlr3 Fixed - ANTLR-367 The code generation for the free method of a recognizer was not distinguishing tree parsers from parsers when it came to calling delegate free functions. This is now corrected. Change 5540 on 2009/01/24 by jimi@jimi.jimi.antlr3 Fixed ANTLR-355 Ensure that we do not attempt to free any memory that we did not actually allocate because the parser rule was being executed in backtracking mode. Change 5539 on 2009/01/24 by jimi@jimi.jimivista.antlr3 Fixed: ANTLR-355 When a C targetted parser is producing in backtracking mode, then the creation of new stream rewrite structures shoudl not happen if the rule is currently backtracking Change 5502 on 2008/12/11 by jimi@jimi.jimi.antlr3 Fixed: ANTLR-349 Ensure that all marker labels in the lexer are 64 bit compatible Change 5473 on 2008/12/01 by jimi@jimi.jimivista.antlr3 Fixed: ANTLR-350 - C runtime use of memcpy Prior change to use memcpy instead of memmove in all cases missed the fact that the string factory can be in a situation where overlaps occur. We now have ANTLR3_MEMCPY and ANTLR3_MEMMOVE and use the two appropriately. Change 5387 on 2008/11/05 by parrt@parrt.spork Fixed x+=. issue with tree grammars; added unit test Change 5325 on 2008/10/23 by parrt@parrt.spork We were all ref'ing backtracking==0 hardcoded instead checking the @synpredgate action.