Mostly white space, but a little more consistency in handling and remove
the use of REJECT (which does actually seem to make a difference, but it
could be just noise).
As far as I can tell, the preprocessor numbers conform with C23 except
for a couple of extensions (both ' and _ work for digit separators, and
d/D work for explicit doubles (since qfcc current defaults to float
instead of double)). This massively cleaned up the numeric rules and
even took care of some UB in the vector parsing code (I'm not sure which
is more surprising: that I didn't see it at the time, or that it was
blindingly obvious now).
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.
While my modified version is needed to actually avoid warnings (vs
upstream git flex), the files still work with debian's flex (with no
warnings). I needed to update (and fix) flex so the lexer line numbers
would be correct.
The improved location tracking isn't used yet, but was fairly invasive
on the bison-flex api.
It also cleans up some of the ancient workarounds for bad flex cores.
It turns out I need to create my own cpp in order to handle glsl's
directives. I've decided to make a unified lexer, and continuation lines
seemed a good place to start.
This fixes the really odd bug of certain string values getting swapped
in vkgen when DEBUG_QF_MEMORY was defined in expr.c. It will also
prevent a lot of fun with floats in the future, I imagine.
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.
I'm not sure why this showed up now (I guess just not enough large
immediate values), but this fixes a segfault in the algtypes test (the
mystery is why it showed up this late).
This gets my `m * p * ~m` code as optimal as possible if my counting is
correct (this does not include the extra extends and add needed to merge
the values). Also, there might be a possibility of recombining some ops
into a vector op, but I'm happy with this.
That is, `x+x -> 2*x` (and similar for higher counts). Doesn't make much
difference for just 2, but it will make collecting scales easier and I
remember some testing showing that `2*x` is faster than `x+x` for
floating point.
Of course, motor-point keeps bouncing around numerically :/
This fixes the motor-point.r test (ie, the sub-type field selector works
on mono-group types now). Still need to sort out something for scalars
(but I imagine that can work only in an @algebra context).
This allows them to be matched with cancelling factors. My fancy zero
test is now just that: a fancy zero:
typedef @algebra(float(3,0,1)) PGA;
typedef PGA.group_mask(0xa) bivector_t;
typedef PGA.group_mask(0x1e) motor_t;
typedef PGA.tvec point_t;
typedef PGA.vec plane_t;
plane_t
apply_motor (motor_t m, point_t p)
{
return (m * p * ~m).vec;
}
0000 nop there were plums...
0001 adjstk 0, 0
apply_motor:
motor.r:32:{
0002 with 2, 0, 1
motor.r:33: return (m * p * ~m).vec;
0003 return (<void>)
The motor-point.r test fails because it uses (m * p * ~m).tvec to get
the value but the type system is slightly broken in that a mono-group
algebra type does not have a structure associated with it and thus the
"missing" field results in 0. Yes, I spent too long chasing that one,
too.
I'd missed this in the previous commit, which was a good thing, really,
as it turns out this was the trigger of the bug that causes my fancy
zero test to become non-zero. It seems the bug is in either
component_sum or in the extend merging.
Or really, the implementers. This gets my fancy zero test down to just
unrecognized permutations of commutative multiplies and dot products
(with the multiplies above the dot products).
While this does "explode" the instruction count (I'll have to collect
like terms later), it does allow for many more opportunities for things
to cancel out to 0 (once (pseudo)commutativity is taken care of).
That is, dot(scale(A,a),scale(B,b)) -> (a*b)*dot(A,B). Does the right
thing when only one side is a scale. No change to the instruction count
in my fancy zero, but it does open more opportunities when I distribute
products.
That is, scale(scale(A,b),c) becomes scale(A,b*c), thus giving the
expression dag more opportunities to find common sub-expressions. My
fancy zero test is down to 20 total instructions (including overhead, or
16 for the actual algebra).
While splitting up the scaled vector into scaled xyz and scaled w does
cost an extra instruction, it allows for other optimizations to be
applied. For one, extends get all the way to the top now, and there are
at most two (in my test cases), thus either break-even or even a slight
reduction in instruction count. However, in the initial implementation,
I forgot to do the actual scaling, and 12 instructions were removed from
my fancy zero case, but real tests failed :P It looks like it's just
distributivity and commutativity holding things back (eg,
omega*gamma*sigma - gamma*omega*sigma: should be 0, but not recognized
as that).
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.
