+ Added read/write notifications of variables. These will be usefull
for providing information for several optimizations. For example
the value of the loop variable of a for loop does matter is the
variable is read after the for loop, but if it's no longer used
or written, it doesn't matter and this can be used to optimize
the loop code generation.
* Moved pocall_internconst to po_internconst because it is not a
calling type at all and it conflicted when inlining of these small
functions was requested
* The whilen and repeatn are now completely unified into whilerepeatn. This
allows the state tracker to change while nodes automatically into
repeat nodes.
* Resulttypepass improvements to the notn. 'not not a' is optimized away and
'not(a>b)' is optimized into 'a<=b'.
* Resulttypepass improvements to the whilerepeatn. 'while not a' is optimized
by removing the notn and later switchting the true and falselabels. The
same is done with 'repeat until not a'.
* foreach gets extra argument for passing local data to the
iterator function
* -CR checks also class typecasts at runtime by changing them
into as
* fixed compiler to cycle with the -CR option
* fixed stabs with elf writer, finally the global variables can
be watched
* removed a lot of routines from cga unit and replaced them by
calls to cgobj
* u32bit-s32bit updates for and,or,xor nodes. When one element is
u32bit then the other is typecasted also to u32bit without giving
a rangecheck warning/error.
* fixed pascal calling method with reversing also the high tree in
the parast, detected by tcalcst3 test
* register allocation is now handled by a class and is mostly processor
independent (+rgobj.pas and i386/rgcpu.pas)
* temp allocation is now handled by a class (+tgobj.pas, -i386\tgcpu.pas)
* some small improvements and fixes to the optimizer
* some register allocation fixes
* some fpuvaroffset fixes in the unary minus node
* push/popusedregisters is now called rg.save/restoreusedregisters and
(for i386) uses temps instead of push/pop's when using -Op3 (that code is
also better optimizable)
* fixed and optimized register saving/restoring for new/dispose nodes
* LOC_FPU locations now also require their "register" field to be set to
R_ST, not R_ST0 (the latter is used for LOC_CFPUREGISTER locations only)
- list field removed of the tnode class because it's not used currently
and can cause hard-to-find bugs
+ nopt.pas, nadd.pas, i386/n386opt.pas: optimized nodes for adding strings
and constant strings/chars together
* n386add.pas: don't copy temp strings (of size 256) to another temp string
when adding
