Add blank lines between functions, between functions and states, between variables and functions or states, between states, and between events.
Or more concisely: add blank lines between events and between all elements at the global level except between variables (that actually describes the algorithm).
Some test cases expected no newlines; fix them.
That was long overdue. Obviously, this is a large commit.
The new nr (node record) class has built-in dump capabilities, rather than using print_node().
SEF always exists now, and is a boolean, rather than using the existence of SEF as the flag. This was changed for sanity. However, other flags like 'X' are still possibly absent, and in some cases the absence itself has meaning (in the case of 'X', its absence means that the node has not yet been analyzed).
Similarly, an event is distinguished from a UDF by checking for the existence of the 'scope' attribute. This trick works because events are not in the symbol table therefore they have no scope. But this should probably be changed in future to something more rational and faster.
A few minor bugfixes were applied while going through the code.
- Some tabs used as Unicode were written as byte strings. Add the u'\t' prefix.
- After simplifying a%1 -> a&0, fold again the node and return. It's not clear why it didn't return, and whether it depended on subsequent passes (e.g. after DCR) for possibly optimizing out the result. Now we're sure.
- A few places lacked a SEF declaration.
- Formatting changes to split lines that spilled the margin.
- Some comment changes.
- Expanded lazy_list_set definition while adapting it to object format. The plan was to re-compress it after done, but decided to leave it in expanded form.
- Added a few TODOs & FIXMEs, resisting the temptation to fix them in the same commit:
- TODO: ~-~-~-expr -> expr + -3.
- FIXME: Now that we have CompareTrees, we can easily check if expr + -expr cancels out and remove a TODO. Low-hanging fruit.
- TODO: Check what we can do when comparing non-SEF and non-CONST values in '>' (current code relies on converting '>' to '<' for applying more optimizations, but that may miss some opportunities).
- FIXME: Could remove one comparison in nt == '&&' or nt == '||'. Low-hanging fruit.
Our previous fix was incomplete, because it failed to detect the last IF in a chain of ELSE IFs. For example:
if (a == 2) llDie(); else if (a) llDie(); else if (a == 3) llDie();
That would be transformed by the IF swapper into:
if (a ^ 2)
if (a)
llDie();
else if (a == 3)
llDie();
else
llDie();
Note that the last 'else' would bind to the last 'if', not to the first one. So the condition is actually like this:
child[1] of an 'if' statement needs to be guarded in {} if the 'else' may belong to the wrong 'if'.
It will belong to the wrong 'if' if child[1] is a (possibly empty) chain of 'if {whatever} else ...', followed by an 'if' without 'else', that is:
if (cond) stmt;
(which was what our previous check did), but also e.g.:
if (cond) stmt; else if (cond) stmt; else if (cond) stmt;
which we neglected to consider in our previous fix.
097c054 introduced a bug that we hadn't caught until now.
In some occasions, it could swap nested conditions in such a way that the 'else' of the outer statement was made to belong to the inner one, like this:
if (a)
if (b)
stuff;
else
stuff;
That is of course parsed with the 'else' belonging to if(b).
Fix implemented at output time, by detecting 'if(a) stmt; else y;' with stmt being an 'if' without 'else', and wrapping the stmt in {} like this: 'if(a){if(b) x;} else y;'. This has some similarity with parenthesis addition.
But the fix has the corner case that, since {} hides visibility of labels, when the inner 'if' has a label as direct child, it can't be swapped lest the label becomes out of scope. So these cases are detected and skipped in the constant folding module.
In the case of 'if(cond);', we transform it to 'cond;', but we forgot to wrap the cond in an EXPR node as required. Fixed too.
When a constant was negative internally, it was output with the sign included. The code was not prepared to handle this, and could therefore cause double minus signs. For example, -2147483648 was output as --2147483648, and -4294967296 was output as --1.
Fixed by adding a space for floats, and by translating the number to the range 2147483648..4294967295 for integers (hex would have worked just as well).
- Separate library loading code into a new module. parser.__init__() no longer loads the library; it accepts (but does not depend on) a library as a parameter.
- Add an optional library argument to parse(). It's no longer mandatory to create a new parser for switching to a different builtins or seftable file.
- Move warning() and types from lslparse to lslcommon.
- Add .copy() to uses of base_keywords, to not rely on it being a frozen set.
- Adjust the test suite.
Lists can't contain lists at runtime, but they can at parse time, so the optimizer must behave properly when handling nested lists. And it didn't, because it neglected to preserve the previous state of self.listmode. So we fix that.
The previous commit didn't work as expected. "from module import var" freezes the value at load time; changing it later has no effect. A reference to the module needs to be used.
Fix that and the similar problem with LSO. Also revert some "from lslcommon import *" introduced earlier.
That also revealed another bug about missing 'cond' in the import list of lslextrafuncs. This should fix all functions that return values on null key input.
Instead of using an option in the command line, use a global in lslcommon, settable by the main program (only the main LSLCalc program, which differs from LSL-PyOptimizer's main, changes it).
Failure to do so caused a regression test to fail. Harmless, because that option is overriden by main, but fixed.
Bug was introduced in commit 397dc89, with the requirement that the 'optimize' option be active for output optimizations to be applied, by forgetting to update the function header to add that default option.
This option normally takes effect through the base class in lsloptimize.py, which doesn't call the optimization techniques if deactivated. However, lsloutput.py is not called by it, and it applied some optimizations on its own.
Fixed on the reading of the optimization options, by filtering them by whether the optimize option is active.
'(float)"-nan"' doesn't return Indet in LSL:
llOwnerSay(llList2CSV([(float)"-nan"])); // outputs "nan", not "-nan"
Therefore, for the output to yield the correct result we have to use a different strategy to generate an indeterminate. We choose '(1e40*0)' which is shorter than the rest.
Also, we don't output infinites as '(float)"[-]inf"' but alwas as '1e40' or '(float)-1e40' (or just '-1e40' if we're in globals).
Commit 5804a9a introduced a bug where having the foldtabs option disabled (normal) prevented optimizations of functions. Fix it for good (hopefully). While on it, rename the nofoldtabs option to warntabs, making it default, and use it to disable a warning when there are tabs in a string.
Adds a new tree node type, SUBIDX, which hopefully should never appear in actual output. If it does, it's prefixed with the string (MISSING TYPE) as a cue to the programmer.
The output module adds parentheses where necessary, depending on the evaluation order in the tree. Or that's the idea. Prone to bugs, let's see how it bodes.
There's also a new hidden option, shrinknames, which automatically enables duplabels due to its nature. The idea is that once general renaming is implemented, in order for label names to not cause collision trouble, they are renamed out of the way with unique names.
Not entirely sure this is really necessary.
