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2016-02-10avoid unnecessary undo token allocations in batch mode: greatly speeds up ↵Robin Haberkorn1-2/+2
batch mode * by using variadic templates, UndoStack::push() is now responsible for allocating undo tokens. This is avoided in batch mode. * The old UndoStack::push(UndoToken *) method has been made private to avoid confusion around UndoStack's API. The old UndoStack::push() no longer needs to handle !undo.enabled, but at least asserts on it. * C++11 support is now required, so variadic templates can be used. This could have also been done using manual undo.enabled checks; or using multiple versions of the template with different numbers of template arguments. The latter could be done if we one day have to support a non-C++11 compiler. However since we're depending on GCC 4.4, variadic template use should be OK. Clang supports it since v2.9. * Sometimes, undo token pushing passed ownership of some memory to the undo token. The old behaviour was relied on to reclaim the memory even in batch mode -- the undo token was always deleted. To avoid leaks or repeated manual undo.enabled checking, another method UndoStack::push_own() had to be introduced that makes sure that an undo token is always created. In batch mode (!undo.enabled), this will however create the object on the stack which is much cheaper than using `new`. * Having to know which kind of undo token is to be pushed (taking ownership or not) is inconvenient. It may be better to add static methods to the UndoToken classes that can take care of reclaiming memory. * Benchmarking certain SciTECO scripts have shown 50% (!!!) speed increases at the highest possible optimization level (-O3 -mtune=native -march=native).
2016-01-28updated copyright to 2016Robin Haberkorn1-1/+1
2015-09-24cleaned up operator precedence codeRobin Haberkorn1-13/+18
* use small values for low precedence
2015-09-23different operators can have the same precedence nowRobin Haberkorn1-10/+24
* SciTECO now has the same operator precedence table as C. * It is numerically important whether different operators have the same precedence. E.g. "5*2/4" used to be evaluated by SciTECO as "5*(2/4)" since division had a higher precedence than multiplication. Within in real (!) numbers this would be the expected evaluation order. Users of other programming languages however would expect the expression to be evaluated as "(5*2)/4" which makes a numerical difference when working with integers. * Operator precedence has been implemented by encoding it into the enumeration values used to represent different operators. Calculating the precedence of a given operator can then be done very efficiently and elegantly (in our case using a plain right shift operation). * documentation updated. We use a precedence table now.
2015-07-22fixed operator precedence listRobin Haberkorn1-3/+3
* necessary since in SciTECO every operator has a different precedence. E.g. successive additions/subtractions cannot be evaluated from left to right (by their associativity). Perhaps this should be changed. * subtraction must have a higher precedence than addition, since (a+b)-c == a+(b-c) * division must have a higher precedence than multiplication since (a*b)/c == a*(b/c). This is not quite true for integer arithmetics. * this fixes expressions like 5-1+1 which were counterintuitively evaluated like 5-(1+1)
2015-03-17fixed invalid memory accesses in the expression stack and reworked ↵Robin Haberkorn1-37/+64
expression stack this was probably a regression from d94b18819ad4ee3237c46ad43a962d0121f0c3fe and should not be in v0.5. The return value of Expressions::find_op() must always be checked since it might not find the operator, returning 0 (it used to be 0). A zero index pointed to uninitialized memory - in the worst case it pointed to invalid memory resulting in segfaults. Too large indices were also not handled. This was probably responsible for recent PPA build issues. Valgrind/memcheck reports this error but I misread it as a bogus warning. I took the opportunity to clean up the ValueStack implementation and made it more robust by adding a few assertions. ValueStacks now grow from large to small addresses (like stack data structures usually do). This means, there is no need to work with negative indices into the stack pointer. To reduce the potential for invalid stack accesses, stack indices are now unsigned and have origin 0. Previously, all indices < 1 were faulty but weren't checked. Also, I added some minor optimizations.
2015-03-16added EL command for setting/getting the EOL modeRobin Haberkorn1-0/+12
2015-02-23implemented to undo stack memory limitingRobin Haberkorn1-2/+2
* acts as a safe-guard against uninterrupted infinite loops or other operations that are costly to undo in interactive mode. If we're out of memory, it is usually too late to react properly. This implementation tries to avoid OOMs due to SciTECO behaviour. We cannot fully exclude the chance of an OOM error. * The undo stack size is only approximated using the UndoToken::get_size() method. Other ways to measure the exact amount of allocated heap (including size fields in every heap object or using sbrk(0) and similar) are either costly in terms of memory or platform-specific. This implementation does not need any additional memory per heap object or undo token but exploits the fact that undo tokens are virtual already. The size of an undo token is determined at compile time. * Default memory limit of 500mb should be OK for most people. * The current limit can be queried with "2EJ" and set with <x>,2EJ. This also works interactively (a bit tricky!) * Limiting can be disabled. In this case, undo token processing is a bit faster. * closes #3
2015-02-11updated copyright to 2015Robin Haberkorn1-1/+1
2014-11-14added ^# (XOR) operatorRobin Haberkorn1-1/+2
also changed precedence of + operator (higher than minus). the effects of this should be minimal
2014-11-11refactored SciTECO runtime errors: moved from parser.cpp to error.cppRobin Haberkorn1-2/+2
* the GError expection has been renamed to GlibError, to avoid nameclashes when working from the SciTECO namespace
2014-11-11added all of SciTECO's declarations to the "SciTECO" namespaceRobin Haberkorn1-0/+4
normally, since SciTECO is not a library, this is not strictly necessary since every library should use proper name prefixes or namespaces for all global declarations to avoid name clashes. However * you cannot always rely on that * Scintilla does violate the practice of using prefixes or namespaces. The public APIs are OK, but it does define global functions/methods, e.g. for "Document" that clashed with SciTECO's "TECODocument" class at link-time. Scintilla can put its definitions in a namespace, but this feature cannot be easily enabled without patching Scintilla. * a "SciTECO" namespace will be necessary if "SciTECO" is ever to be turned into a library. Even if this library will have only a C-linkage API, it must ensure it doesn't clutter the global namespace. So the old "TECODocument" class was renamed back to "Document" (SciTECO::Document).
2014-02-15updated Copyright to year 2014Robin Haberkorn1-1/+1
2014-02-15report stack overflows as errors & fixed ValueStack dtorRobin Haberkorn1-1/+5
* ValueStack destruction might have resulted in Segfaults at shutdown
2013-03-17^E\ string building character to format numberRobin Haberkorn1-0/+2
* new Expressions::format() * may be used format numbers as part of arrays (Q-Register names)
2013-02-22use typedef for SciTECO integers and make it configurable at configure timeRobin Haberkorn1-7/+7
* storage size should always be 64 (gint64) to aid macro portability * however, for performance reasons users compiling from source might explicitly compile with 32 bit integers
2013-01-19updated copyright (2012-2013)Robin Haberkorn1-1/+1
2012-12-04added copyright notice to every source fileRobin Haberkorn1-0/+17
2012-12-04autoconf preparation: move everything into src/ subdirRobin Haberkorn1-0/+194