This takes advantage of the ud-chains to follow the trail of pointer
assignments looking for an address. This gets array element assignments
surviving across blocks when the array itself is passed to a function.
It doesn't help when the address of the element is taken though. I think
that's a dags problem and probably needs du-chains. Also, the ud-chain
creation should probably be done in two passes so the newly found
information can be recorded.
Def and kill are still handled in flow_analyze_statement, but this makes
call meta data more consistent between v6 and ruamoko progs, allowing
the statement use chain to be used for call argument analysis. It even
found a bug in the extraction of param counts from the call instruction.
I had missed the flowvar clearing for auxiliary use/def/kill operands.
It's possible it wasn't necessary at the time since the operands were
added just for dealloc checking, but there's every reason it could
become necessary.
The first use will be pointer analysis for function arguments where the
argument points to an array to mark the array as live, but I'm sure
there'll be plenty of other uses.
A partial write to a def should not define the whole def, thus
def_visit_all's overlap parameter now has a flag that prevents a visit
to the main def when accessing the def from an alias def. This prevents
a lot of spurious kills and defines in flow analysis.
The array access code was loading the vector, modifying the element,
then forgetting to write the modified vector back to whence it came.
However, that would be rather sub-optimal, so now when the vector is
accessed by a pointer, the array code switches to field access to get at
the vector element thus avoiding the need to copy the whole vector.
Needed for proper analysis (ud-chains etc). Of course, it was then
necessary to remove the parameter defs from the uninitialized defs.
Also, plug a couple of memory leaks (forgot to free some temporary
sets).
That is, `array + offset`. This actually works around the bug
highlighted by arraylife.r (because the array is explicitly used), but
is not a proper solution, so that test still fails of course. However,
with this, it's no longer necessary to use `&array[index]` instead of
`array + index`.
I could never remember what any of the numbers meant. While define is
still a little fuzzy (they're (pseudo)statement numbers), at least now
I'll always know that the numbers are the define set. Also, having the
flow address of the variable helps with understanding the reaching defs
output.
I had messed up the handling of declarators for combinations of pointer,
function, and array: the pointer would get lost (and presumably arrays
of functions etc). I think I had gotten confused and thought things were
a tree rather than a simple list, but Holub set me straight once again
(I've never regretted getting that book). Once I understood that, it was
just a matter of finding all the places that needed to be fixed. Nicely,
most of the duplicated code has been refactored and should be easier to
debug in the future.
The type system rewrite had lost some of the checks for function fields.
This puts the actual code in the one place and covers parameters as well
as globals.
Internally, * is not really a valid operator for vectors since it can
have many meanings. This didn't cause trouble until trying to build
everything in game-source (since there's still a lot of legacy code in
there).
The precedence check changes done in
63795e790b seem to have been incorrect
(game-source/ctf produced many false positives), so putting that check
against '=' back into the code seems like a good idea (no more false
positives). That sounds a bit cargo-cult, but I'm really not sure what I
was thinking when I did the changes (probably just tired).
This applies only to the top-level scope of the function. I'm not sure
if it's right for traditional quakec code, but that can be adjusted
easily enough.
The symtab code itself cares only about global/not global for the size
of the hash table, but other code can use the symtab type for various
checks (eg, parameter shadowing).
Along with QuakeC's, of course. This fixes type typeredef2 test (a lot
of work for one little syntax error). Unfortunately, it came at the cost
of requiring `>>` in front of state expressions on C-style functions
(QuakeC-style functions are unaffected). Also, there are now two
shift/reduce conflicts with structs and unions (but these same conflicts
are in gcc 3.4).
This has highlighted the need for having the equivalent of the
expression tree for the declaration system as there are now several
hacks to deal with the separation of types and declarators. But that's a
job for another week.
The grammar constructs for declarations come from gcc 3.4's parser (I
think it's the last version of gcc that used bison. Also, 3.4 is still
GPL 2, so no chance of an issue there).
This simplifies type type_specifier rule significantly as now TYPE_SPEC
(was TYPE) includes all types and their basic modifiers (long, short,
signed, unsigned). This should allow me to make the type system closer
to gcc's (as of 3.4 as that seems to be the last version that used a
bison parser) and thus fix typeredef2.
Once a unicode char (ie, > 127) was used, any ascii chars would get the
tail of the last unicode char resulting in broken utf-8 streams. The
resulting null glyph boxes were not very appealing.
This fixes the basic vecconst test (extending it to other types breaks
because long and ulong are not properly supported yet). The conversion
is done by the progs VM rather than writing another 256 conversions
(though loops could be used). This works nicely as a test for using the
VM to help with compiling.
While the option to make '*' mean dot product for vectors is important,
it breaks vector scaling in ruamoko progs as the resultant vector op
becomes a dot product instead of the indented hadamard product (ie,
component-wise).
The support for the new vector types broke compiling code using
--advanced. Thus it's necessary to ensure vector constants are
float-type and vec3 and vec4 are treated as vector and quaternion, which
meant resurrecting the old vector expression code for v6p progs.
The method is still held by known_methods, so freeing it causes grief.
However, it may cause a leak thus the free is only commented out. More
investigation is needed. I'm surprised the problem didn't show on linux,
but cygwin-native hit it and valgrind on linux found the spot :)
While it does get a bit cluttered currently, being able to see the
contents of structures makes a huge difference. Also highlights that
vector immediates do not get the correct type encodings.
This fixes the internal error generated by the likes of
`(sv_gravity * '0 0 1')` where sv_gravity is a float and `'0 0 1'` is an
ivec3: the vector is promoted to vec3 first so that expanding sv_gravity
is expanded to vec3 instead of ivec3 (which is not permitted for a
float: expansion requires the destination base type to be the same as
the source).
For now, anyway, as the generated code looks good. There might be
problems with actual pointer expressions, but it allows entity.field to
work as expected rather than generate an ICE.
