I never did like overloaded_function_t as a name, and with the
introduction of generic functions (or templates, I guess?) meta-function
makes more sense to me.
Most of them were noise from the type const correctness pass, but the
qc field function handling was always dubious (though in practice safe
due to how the type was built, but...). The remaining casts outside of
type.c need some thought.
With this, genFType and genDType functions are now treated separately
and expanding to all components (single row or column matrices are not
supported (at this stage, anyway) for generic parameters).
That is, `@generic(...) { ... };`, which is handy for bulk declarations
(such as for glsl). This proved to be a lot harder than expected, I
suspect handling of specifiers needs a lot of work.
It doesn't properly differentiate between (treats genDType as being the
same as genFType):
@generic(genFType=@vector(float)) genFType radians(genFType degrees);
@generic(genDType=@vector(double)) genDType radians(genDType degrees);
but this is due to problems with how the type is built from
@vector(float) and @vector(double). However, I thought it was about time
I got some of this into git.
Also, `@generic(...) { ... };` blocks don't work properly (they lose the
generic info): need to get a little smarter about handling generic scope
in `external_def_list`.
While they might be ok, I expect them to cause some issues when doing
compile-time evaluations of type expressions, so use of dags seems to be
a premature optimization. However, as the "no dags" flag is propagated
to parent expression nodes, it may prove useful in other contexts.
The expression grammar has been tidied up and some basic checks are made
of parameters to the type functions. Also, type parameters are looked up
so parsing now works properly. However, the type parameters are not used
correctly, so function generation doesn't work.
The semantics are only partially implemented (generic types not yet
generated), but the generic scope for function declarations seems to be
working as intended in that it gets inserted in the scope chain and
removed at the end of the declaration.
The end goal is to allow generic and/or template functions, but this
allows types to be specified parametrically, eg vectors of specific type
and width, with widths of one becoming scalars.
Matrices are currently completely broken as I haven't decided on how to
represent the columns (rows is represented by width (column-major
storage)), and bools are only partially supported (need to sort out
32-bit vs 64-bit bools).
No semantics yet, but qfcc can parse some of QF's shaders. The grammar
mostly follows that in the OpenGL Shading Language, Version 4.60.7 spec,
but with a few less tokens.
This gets the types such that either there is only one definition, or C
sees the same name for what is essentially the same type despite there
being multiple local definitions.
The syntax is not at all correct at this stage (really, just a copy of
Ruamoko), but the keyword table exists (in the wrong place) and the
additional basic types (bool, bvecN and (d)matNxM) have been added.
Boolean base type is currently just int, and matrices have 0 width while
I think about what to use, but finally some progress after several
months' hiatus.
This allows the dags code to optimize the return values, and when I make
the node killing by function calls less aggressive, should make for many
more potential CSE optimizations.
The fix in bdafdad0d5 for
`while (count--)` never did appeal to me. I think I understood the core
problem at the time, but I hadn't figured out how to use a var's
use/define sets to detect the write-before-read. Using them allows the
special handling for flow control to be removed, making things more
robust. The function call handling has been superfluous since the
Ruamoko instruction set required the auxiliary operands on the call
statements.
Two birds with one stone: eliminates most of the problems with going
const-correct with expr_t, and it make dealing with internally generated
expressions at random locations much easier as the set source location
affects all new expressions created within that scope, to any depth.
Debug output is much easier to read now.
There were a few places where some const-casts were needed, but they're
localized to code that's supposed to manipulate types (but I do want to
come up with something to clean that up).
I'm not sure the regressive product is right (overall sign), but that's
actually partly a problem in the math itself (duals and the regressive
product still get poked at, so it may be just a matter of
interpretation).
The switch to using expression dags instead of trees meant that the
statement generator could traverse sub-expressions multiple times. This
is inefficient but usually ok if there are no side effects. However,
side effects and branches (usually from ?:, due to labels) break: side
effects happen more than once, and labels get emitted multiple times
resulting in orphaned statement blocks (and, in the end, uninitialized
temporaries).
This makes a slight improvement to the commutator product in that it
removes the expand statement, but there's still the problem of (a+a)/2.
However, at least now the product is correct and slightly less abysmal.
There's no guarantee the source file is in a writable directory (in
fact, it is very definitely in a read-only directory when running
`make distcheck`). However, it is reasonable to assume the output file
is being written to a writable directory thus default the object file
directory to that of the output file, but still use the source file's
name for the object file name.
Fixes#51
It just feels cleaner than unnecessarily copying token chains. It turns
out that the core problem was just order of operations in next_token:
moving the pending_macro code to after arg/macro detection seems to be
correct (even bare `G LPAREN() 0)` is *not* expanding `G`, as expected).
I got tired of the way the separate token types for macro expansion and
the rest of the preprocessor parser were handled. This makes them a
little more unified. Macro expansion seems to be slightly broken again
in that min/max/bound mess up badly, and __VA_OPT__ does things in the
wrong order, but I wanted to get this in as a checkpoint.
__VA_ARGS__ seems to be working but __VA_OPT__ still needs a lot of work
for dealing with its expansions, but basic error checking and simple
expansions seem to work.
Macros now store their arguments and have a cursor pointing to the next
token to take from their expansion list. While not checked yet, this
will make avoiding recursive macro invocations much easier. More
importantly, it's a step closer to correct argument expansion (though
token pasting is currently broken).
-D options weren't counting correctly so build_cpp_args was writing past
the end of the array allocated for command line arguments
parse_cpp_name had an out-by-one resulting in reading past the end of
the string.
The qfcc system include path was being set in the wrong place (not sure
why I thought that was right), and not respecting no_default_paths.
-M was generating preprocessor output when it should not have been,
resulting in corrupted dependency files.
Or at least mostly so. The __QFCC__ define isn't visible, and it seems
undef might not be working properly (ruamoko/lib/types.r doesn't
compile). Of course, there's still the issue of whether it's compiling
correctly.
In addition to cleaning up the old flex line rules, this improves
handling of the '# num "file" flags' from cpp to at least parse the
additional flags (support for the system header flag might come later,
but I doubt the extern-c flag will have much meaning).
QuakePascal has lost its line directive handling (no errors, but dead
rules) for now. Eventually the lexers will be merged.
Really, function-type macros expand too, but incorrectly as the
parameters are not parsed and thus not expanded, but this gets the basic
handling implemented, including # and ## processing.
This will be used for unifying preprocessing and parsing, the idea being
that the tokens will be recorded for later expansion via macros, without
the need to retokenize.
It's now meant only for ALLOC. Interestingly, when DEBUG_QF_MEMORY is
defined in expr.c, something breaks badly with vkgen (no sniffles out of
valgrind, though), but everything is fine with it not defined. It seems
there may be some unpleasant UB going on somewhere.
This fixes the motor test :) It turns out that every lead I had
previously was due to the disabling of that feature "breaking" dags
(such that expressions wouldn't be found) and it was the dagged
multi-vector components getting linked by expr->next that made a mess of
things.
Or at least mostly so (there are a few casts). This doesn't fix the
motor bug, but I've wanted to do this for over twenty years and at least
I know what's not causing the bug. However, disabling fold_constants in
expr_algebra.c does "fix" things, so it's still a good place to look.
They don't have much effect that I've noticed, but the expression dags
code does check for commutative expressions. The algebra code uses the
anticommutative flag for cross, wedge and subtract (unconditional at
this stage). Integer ops that are commutative are always commutative (or
anticommutative). Floating point ops can be controlled (default to non),
but no way to set the options currently.
Especially binary expressions. That expressions can now be reused is
what caused the need to make expression lists non-invasive: the reuse
resulted in loops in the lists. This doesn't directly affect code
generation at this stage but it will help with optimizing algebraic
expressions.
The dags are per sequence point (as per my reading of the C spec).
Finally, that little e. is cleaned up. convert_name was a bit of a pain
(in that it relied on modifying the expression rather than returning a
new one, or more that such behavior was relied on).
That is, passing int constants through ... in Ruamoko progs is no longer
a warning (still is for v6p and v6 progs). I got tired of getting the
warning for sizeof expressions when int through ... hasn't been a
problem for even most v6p progs, and was intended to not be a problem
for Ruamoko progs.
But really only for memset and memmove because they need to use an int
alias of the variable and it may be only that alias that sets a much
larger variable.
Because the aliases were treated as live, every alias of a temp resulted
in an assignment, which proved to be quite significant (4-5 assignments
in some simple GA expressions). By using an alias node in the dag, the
unaliased temp can be marked live while the alias is treated as an
operation rather than an operand. Now my GA expressions have no
superfluous assignments (generally no assignments at all).
Simple k-vectors don't use structs for their layout since they're just
an array of scalars, but having the structs for group sets or full
multi-vectors makes the system alignment agnostic.
And geometric algebra vectors. This does break things a little in GA,
but it does bring qfcc's C closer to standard C in that sizeof respects
the alignment of the type (very important for arrays).
It's implemented as the Hodge dual, which is probably reasonable until
people complain. Both ⋆ and ! are supported, though the former is a
little hard to see in Consola.
The singleton alias resulted in the adjusted swizzles being corrupted
when for the same def. Other than adding properly sized swizzles
(planned), the simplest solution is to (separately) allow alias that
stick out from from the def.
Currently via only the group mask (which is really horrible to work
with: requires too much knowledge of implementation details, but does
the job for testing), but it got some basics working.
Also, correct the handling of scalars in dot and wedge products: it
turns out s.v and s^v both scale. However, it seems the CSE code loses
things sometimes.
This makes working with them much easier, and the type system reflects
what's in the multi-vector. Unfortunately, that does mean that large
algebras will wind up having a LOT of types, but it allows for efficient
storage of sparse multi-vectors:
auto v = 4*(e1 + e032 + e123);
results in:
0005 0213 1:0008<00000008>4:void 0:0000<00000000>?:invalid
0:0044<00000044>4:void assign (<void>), v
0006 0213 1:000c<0000000c>4:void 0:0000<00000000>?:invalid
0:0048<00000048>4:void assign (<void>), {v + 4}
Where the two source vectors are:
44:1 0 .imm float:18e [4, 0, 0, 0]
48:1 0 .imm float:1aa [4, 0, 0, 4]
They just happen to be adjacent, but don't need to be.
This gets only some very basics working:
* Algebra (multi-vector) types: eg @algebra(float(3,0,1)).
* Algebra scopes (using either the above or @algebra(TYPE_NAME) where
the above was used in a typedef.
* Basis blades (eg, e12) done via procedural symbols that evaluate to
suitable constants based on the basis group for the blade.
* Addition and subtraction of multi-vectors (only partially tested).
* Assignment of sub-algebra multi-vectors to full-algebra multi-vectors
(missing elements zeroed).
There's still much work to be done, but I thought it time to get
something into git.
If a symbol is not found in the table and a callback is provided, the
callback will be used to check for a valid procedural symbol before
moving on to the next table in the chain. This allows for both tight
scoping of the procedural symbols and caching.
Due to joys of pointers and the like, it's a bit of a bolt-on for now,
but it works nicely for basic math ops which is what I wanted, and the
code is generated from the expression.
I never liked it, but with C2x coming out, it's best to handle bools
properly. I haven't gone through all the uses of int as bool (I'll leave
that for fixing when I encounter them), but this gets QF working with
both c2x (really, gnu2x because of raw strings).
The warning flag check worked too well: it enabled the warning and
autoconf's default main wanted the const attribute. The bug has been
floating around for a while, it seems.
I'm not certain this is correct, but it seems to me that du-chains are
the same information as ud-chains, but from the defining statement's
point of view instead of that of the using statement.
I think the current build_element_chain implementation does a reasonable
job, but I'm in the process of getting designated initializers working,
thus it will become important to ensure uninitialized members get
initialized.
I never liked the various hacks I had come up with for representing
resource handles in Ruamoko. Structs with an int were awkward to test,
pointers and ints could be modified, etc etc. The new @handle keyword (@
used to keep handle free for use) works just like struct, union and
enum in syntax, but creates an opaque type suitable for a 32-bit handle.
The backing type is a function so v6 progs can use it without (all the
necessary opcodes exist) and no modifications were needed for
type-checking in binary expressions, but only assignment and comparisons
are supported, and (of course) nil. Tested using cbuf_t and QFile: seems
to work as desired.
I had considered 64-bit handles, but really, if more than 4G resource
objects are needed, I'm not sure QF can handle the game. However, that
limit is per resource manager, not total.
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.
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).
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.
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).
While swizzle does work, it requires the source to be properly aligned
and thus is not really the best choice. The extend instruction has no
alignment requirements (at all) and thus is much better suited to
converting a scalar to a vector type.
Fixes#30
As a class's ivars are built up by inheritance, but with only that
class's ivars in the symbol table, is is necessary to include an offset
based on the super class's ivars in order to ensure alignments are
respected. This is achieved via the new `base` parameter to
build_struct(), which is used to offset the current size while
calculating the aligned offset of the symbols. The parameter is ignored
for unions, as they always start at 0. The ivars for the current class
still have a base offset of 0 until they are actually added to the
class.
Fixes#29
The alignment is specified as a power of 2 (ie, actual alignment = 1 <<
alignment) allowing old object files to be compatible (as their
alignment is 0). This is necessary for (in part for #30) as it turned
out even global vectors were not aligned correctly.
Currently, only data spaces even vaguely respect alignment. This may
need to be fixed in the future.
Most were pretty easy and fairly logical, but gib's regex was a bit of a
pain until I figured out the real problem was the conditional
assignments.
However, libs/gamecode/test/test-conv4 fails when optimizing due to gcc
using vcvttps2dq (which is nice, actually) for vector forms, but not the
single equivalent other times. I haven't decided what to do with the
test (I might abandon it as it does seem to be UD).
The destination operand must be a full four component vector, but the
source can be smaller and small sources do not need to be aligned: the
offset of the source operand and the swizzle indices are adjusted. The
adjustments are done during final statement emission in order to avoid
confusing the data flow analyser (and that's when def offsets are known).
Having three very similar sets of code for outputting values (just for
debug purposes even) got to be a tad annoying. Now there's only one, and
in the right place, too (with the other value code).
I'd created new_value_expr some time ago, but never used it...
Also, replace convert_* with cast_expr to the appropriate type (removes
a pile of value check and create code).
Use with quaternions and vectors is a little broken in that
vec4/quaternion and vec3/vector are not the same types (by design) and
thus a cast is needed (not what I want, though). However, creating
vectors (that happen to be int due to int constants) does seem to be
working nicely otherwise.
Nicely, I was able to reuse the generated conversion code used by the
progs engine to do the work in qfcc, just needed appropriate definitions
for the operand macros, and to set up the conversion code. Helped
greatly by the new value load/store functions.
pr_type_t now contains only the one "value" field, and all the access
macros now use their PACKED variant for base access, making access to
larger types more consistent with the smaller types.
In working with vectors and matrices while testing the scene wrappers, I
found that there was a fair bit of confusion about how large something
could be. Return values can be up to 32 words (but qfcc wasn't aware of
that), parameters were limited to 4 words still (and possibly should be
for varargs), and temp defs were limited to 8 words (1 lvec4). Temps are
used for handling return values (at least when not optimizing) and thus
must be capable of holding a return value, and passing large arguments
through *formal* parameters should be allowed. It seems reasonable to
limit parameter sizes to return value sizes.
A temp and a move are still used for large return values (4x4 matrix),
but that's an optimization issue: the code itself is at least correct.
Currently only via pragma (not command line options), but I needed to
test the concept. Converting legacy code is just too error prone.
Telling the compiler how to treat the operator makes more sense. When *
acts as @dot with Ruamoko progs, the result is automatically aliased as
a float as this is the legacy meaning (ie, float result for dot
product).
This is achieved by marking a void function with the void_return
attribute and then calling that function in an @return expression.
@return can be used only inside a void function and only with void
functions marked with the void_return attribute. As this is intended for
Objective-QC message forwarding, it is deliberately "difficult" to use
as returning a larger than expected value is unlikely to end well for
the calling function.
However, as a convenience, "@return nil" is allowed (in a void
function). It always returns an integer (which, of course,can be
interpreted as a pointer). This is safe because if the return value is
ignored, it will go into the progs return buffer, and if it is not
ignored, it is the smallest value that can be returned.
Having to remember to copy yet another specifier bit was getting
tedious, so use a union of a struct with the bitfields and an unsigned
int to access them in parallel. Makes for a tidier spec_merge, and one
less headache.
The command line option works the same way as
--advanced/traditional/extended, as does the pragma. As well, raumoko
(alternative spelling) can be used because both are legitimate and some
people may prefer one spelling over the other.
As always, use of the pragma is at one's own risk: its intended use is
forcing the target in the unit tests.
dvec4, lvec4 and ulvec4 need to be aligned to 8 words (32 bytes) in
order to avoid hardware exceptions. Rather than dealing with possibly
mixed alignment when a function has 8-word aligned locals but only
4-word aligned parameters, simply keep the stack frame 8-word aligned at
all times.
As for sizes, the temp def recycler was written before the Ruamoko ISA
was even a pipe dream and thus never expected temp def sizes over 4. At
least now any future adjustments can be done in one place.
My quick and dirty test program works :)
dvec4 xy = {1d, 2d, 0d, 0.5};
void printf(string fmt, ...) = #0;
int main()
{
dvec4 u = {3, 4, 3.14};
dvec4 v = {3, 4, 0, 1};
dvec4 w = v * xy + u;
printf ("[%g, %g, %g, %g]\n", w[0], w[1], w[2], w[3]);
return 0;
}
They're now properly part of the type system and can be used for
declaring variables, initialized (using {} block initializers), operated
on (=, *, + tested) though much work needs to be done on binary
expressions, and indexed. So far, only ivec2 has been tested.
Ruamoko passes va_list (@args) through the ... parameter (as such), but
IMP uses ... to defeat parameter type and count checking and doesn't
want va_list. While possibly not the best solution, adding a no_va_list
flag to function types and skipping ex_args entirely does take care of
the problem without hard-coding anything specific to IMP.
The system currently just sets some bits in the type specifier (the
attribute list should probably be carried around with the specifier),
but it gets the job done for now, and at least gets things started.
This makes it much easier to check (and more robust to name changes),
allowing for effectively killing the node to which the variable being
addressed is attached. This fixes the incorrect address being used for
va_list, which is what caused double-alias to fail.
Since Ruamoko progs must use lea to get the address of a local variable,
add use/def/kill references to the move instruction in order to inform
flow analysis of the variable since it is otherwise lost via the
resulting pointer (not an issue when direct var reference move can be
used).
The test and digging for the def can probably do with being more
aggressive, but this did nicely as a proof of concept.
This is necessary to get statement disassembly working, and likely
debugging in general. locals is the total size of the stack frame and
thus reaches above the function-entry stack pointer, and params_start is
the local space relative start of the parameters. Thus, knowing the
function-entry stack pointer, the bottom of the locals space can be
found by subtracting params_start, and the top of the locals space by
adding (locals - params_start).
This gets all the sections of the progs file nicely aligned and the code
easier to read with the offset and size calculations not being spread
through the function. ivar-struct-return now works when compiled for
Ruamoko.
The goal was to get lea being used for locals in ruamoko progs because
lea takes the base registers into account while the constant pointer
defs used by v6p cannot. Pointer defs are still used for gobals as they
may be out of reach of 16-bit addressing.
address_expr() has been simplified in that it no longer takes an offset:
the vast majority of the callers never passed one, and the few that did
have been reworked to use other mechanisms. In particular,
offset_pointer_expr does the manipulations needed to add an offset
(unscaled by type size) to a pointer. High-level pointer offsets still
apply a scale, though.
Alias expressions now do a better job of hanling aliasing of aliases by
simply replacing the target type when possible.
The parameter defs are allocated from the parameter space using a
minimum alignment of 4, and varargs functions get a va_list struct in
place of the ...
An "args" expression is unconditionally injected into the call arguments
list at the place where ... is in the list, with arguments passed
through ... coming after the ...
Arguments get through to functions now, but there's problems with taking
the address of local variables: currently done using constant pointer
defs, which can't work for the base register addressing used in Ruamoko
progs.
With the update to test-bi's printf (and a hack to qfcc for lea),
triangle.r actually works, printing the expected results (but -1 instead
of 1 for equality, though that too is actually expected). qfcc will take
a bit longer because it seems there are some design issues in address
expressions (ambiguity, and a few other things) that have pretty much
always been there.
While all base registers can be used for any purpose at any time (this
is why the with instruction has hard-absolute modes: you can never get
permanently lost), qfcc currently uses the convention of register 0 for
globals and register 1 for stack locals (params, locals, function args).
The register used to access a def is stored in the def and that is used
to set the register bits in the instruction opcode.
The def code actually doesn't know anything about any conventions: it
assumes all defs are global for non-temp defs (the function code updates
the defs before emitting code) and the current function provides the
register to use for any temp defs allocated while emitting code.
Seems to work well, but debug is utterly messed up (not surprised, that
will be tricky).
Still need to get the base register index into the instructions, but I
think this is it for basic code generation. I should be able to start
testing Ruamoko properly fairly soon :)
Thanks to the use/def/kill lists attached to statements for pseudo-ops,
it turned out to be a lot easier to implement flow analysis (and thus
dags processing) than I expected. I suspect I should go back and make
the old call code use them too, and probably several other places, as
that will greatly simplify the edge setting.
The means that the actual call expression is not in the statement lint
of the enclosing block expression, but just its result, whether the call
is void or not. This actually simplifies several things, but most
importantly will make Ruamoko calls easier to implement.
The test is because I had some trouble with double-calls, and is how I
found the return-postop issue :P
Since Ruamoko now uses the stack for parameters and locals, parameters
need to come after locals in the address space (instead of before, as in
v6 progs). Thus use separate spaces for parameters and locals regardless
of the target, then stitch them together appropriately for the target.
The third space is used for allocating stack space for arguments to
called functions. It us not used for v6 progs, and comes before locals
in Ruamoko progs.
Other than the return value, and optimization (ice, not implemented)
calls in Ruamoko look like they'll work.
This seems to be the most reasonable approach to allocating space for
function call parameters without using push and pop (or adding to the
stack pointer), though it's probably good even when using push and pop
to help keep things aligned.
Operand width is encoded in the instruction opcode, so the width needs
to be accounted for in order to select the correct instruction. With
this, my little test generates correct code for the ruamoko ISA (except
for return, still fails).
long is ignored for double, and v6p progs are stuck with 32 bits for
longs (don't feel like extending v6p any further), but the basics are
there for Ruamoko.
short is ignored for ints because the minimum size is 32, and signed is
just noise for ints anyway (and no chars, so...).
unsigned, however, is finally implemented properly (or at least seems to
be working correctly: tests pass after getting things compiling again,
and lt.u is used where it should be :)
And other related fields so integer is now int (and uinteger is uint). I
really don't know why I went with integer in the first place, but this
will make using macros easier for dealing with types.
They are both gone, and pr_pointer_t is now pr_ptr_t (pointer may be a
little clearer than ptr, but ptr is consistent with things like intptr,
and keeps the type name short).
This includes calls and unconditional jumps, relative and through a
table. The parameters are all lumped into the one object, with some
being unused by the different types (eg, args and ret_type used only by
call expressions). Just having nice names for the parameters (instead of
e1 and e2) makes it nice, even with all the sub-types lumped together.
No mysterious type aliasing bugs this time ;)
The move operator names are definitely obsolete (due to dropping the
expressions a year or two ago) and the precedence checks seem to be
handled elsewhere. Memset and state expressions went away a while back
too.
