Thanks to Deek for the suggestion: the mode (ie, src and dst types) are
encoded in st->b. Actual code not written yet, but this frees up 13
instructions: now have 74 available for really interesting stuff :)
The call1-8 instructions have been removed as they are really not needed
(they were put in when I had plans of simple translation of v6p progs to
ruamoko, but they joined the dinosaurs).
The call instruction lost mode A (that is now return) and its mode B is
just the regular function access. The important thing is op_c (with
support for with-bases) specifies the location of the return def.
The return instruction packs both its addressing mode and return value
size into st->c as a 3.5 value: 3 bits for the mode (it supports all
five addressing modes with entity.field being mode 4) and 5 for the
size, limiting return sizes to 32 words, which is enough for one 4x4
double matrix.
This, especially with the following convert patch, frees up a lot of
instructions.
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 ;)
While it doesn't cover the addressing modes, it does match the bit
pattern used in the Ruamoko instruction set. It will make selecting
branch instructions easier (especially for Ruamoko).
Now they're in a much more consistent arrangement, in particular with
the comparison opcodes if the conditional branch instructions are
considered to be fast comparisons with zero (ifnot -> ifeq, if -> ifne,
etc). Unconditional jump and call fill in the gaps. The goal was to get
them all in an arrangement that would work as a small enum for qfcc: it
can use the enum directly for the ruamoko IS, and a small map array for
v6p (except for call).
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.
While this was a pain to get working, that pain only went to prove the
value of using proper "types" (even if only an enum) for different
expression types: just finding all the places to edit was a chore, and
easy to make mistakes (forgetting bits here and there).
Strangely enough, this exposed a pile of *type* aliasing bugs (next
commit).
Both pr_type_size and pr_type_name. I want to macroize the enum, but
need to sort out the clutter of headers first, just need to decide on
naming. This at least sorts out the missed values for now.
v6 vs v6p are more or less as before, with ruamoko added in. qfcc will
now try (and fail, due to the opcode table opnames being wrong) to
create ruamoko progs when given the ruamoko target option.
At this stage, I doubt emit.c will need to know the details of the
target (v6, v6p, ruamoko) since the instruction formats are identical,
just different meanings for the opcode itself.
This allows v6, v6p (older QF VM) or ruamoko (new QF VM) to be targeted.
Currently defaults to v6p to allow QF to continue building without too
much hassle.
While qfcc dealing sensibly with mixed target VMs in the object files
has always been an outstanding issue, with the new instruction set it
has become a priority. Most importantly, this should allow QF to
continue building while I work on qfcc targeting the new IS.
It does little good for documentation to refer to fields that don't
exist (because a certain someone forgot to change the docs when changing
the field names, I wonder who :P).
In some cases, gcc-11 does a good enough job translating normal looking
C expressions so use just those, but other times need to dig around for
an appropriate intrinsic.
Also, now need to disable psapi warnings when compiling for anything
less than avx.
The bug (alignment issues with AVX on windows) seems to have in gcc from
the 4.x days, and is still present in 11.2: it does not ensure stack
parameters that need 32 byte alignment are aligned. Telling gcc to use
the sysv abi (safe on a static function) lets gcc do what it does for
linux (usually pass the parameters in registers, which it seems to have
done).
And partial implementations in qfcc (most places will generate an
internal error (not implemented) or segfault, but some low-hanging fruit
has already been implemented).
As I expect to be tweaking things for a while, it's part of the build
process. This will make it a lot easier to adjust mnemonics and argument
formats (tweaking the old table was a pain when conventions changed).
It's not quite done as it still needs arg widths and types.
While working on the new opcode table, I decided a lot of the names were
not to my liking. Part of the problem was the earlier clash with the
v6p opcode names, but that has been resolved via the v6p tag.
Use the new "1" versions of loadvec3 to get a 1 in w to avoid
divide-by-zero errors, and use the correct type for longs (forgot to
change i to l on the vector types).
Always setting w to 0 made it impossible to use the resulting 4d vectors
in division-based operations as they would result in divide-by-zero and
thus an unavoidable exception (CPUs don't like integer div-by-zero).
I'll probably add similar for float and double, but they're not as
critical as they'll just give inf or nan. This also increases my doubts
about the value of keeping 3d vector operations.
