This is the bulk of the work for recording the resource pointer with
with builtin data. I don't know how much of a difference it makes for
most things, but it's probably pretty big for qwaq-curses due to the
very high number of calls to the curses builtins.
Closes#26
Now that the data is fetched from the correct location, the locals view
is useful again :). However, there seems to be a problem with array
views: not sure they're showing the correct data as I was getting
unexpected values in the display but normal vars seem to be ok.
While the .tmp defs weren't too much clutter in v6p progs, the .arg defs
in Ruamoko progs make for a lot of noise. Showing only user defs (those
without a leading .) makes for a much more usable locals display.
The zone memory block header is 64 bytes, so allocating a single 8 byte
selector is rather wasteful. Instead, allocate selectors in large chunks
(currently 64) and divvy them out as needed. Significantly reduces
memory pressure in large Ruamoko progs.
When the def can be found. This fixes direct assignments to arrays (and
probably structs) getting lost when the array is later read using a
variable index.
While there is still plenty of improvement to go (mostly in qfcc to take
advantage of the new features, but there's room for optimization in the
VM), the Ruamoko ISA seems to be working quite well.
Float is not int, and Ruamoko has only int ifz/ifnz, which will fail for
-0.0 (0x80000000 when viewed as an int). And then there's nan, but I
haven't seen too many of those in quake.
I suspect this is an ancient bug that wasn't noticed due to not looking
at progs.src compiled code enough, but it makes the first statements of
the function point to the correct line instead of a forward declaration.
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).
These add legacy support for basic float bitops (& | ^ ~). Avoiding the
instructions would require tot only the source to be converted, but also
the servers (as they do access those fields), and this seemed to be too
much.
It's not enforced a this stage, and it would be easy enough to handle,
but it turns out all the standard quake and quakeworld progs never used
... for the print functions: the behavior of PF_VarString was
undocumented and so... tough :P.
I had forgotten that unsigned division was different from signed
division (rather silly of me). However, with some testing and analysis,
unsigned true modulo is not needed as it's not possible to have
negative inputs and thus it's the same as remainder.
This is a very tiny optimization, but there's no point in adjust the
stack if there's no actual adjustment. I didn't bother with it initially
because I thought it wouldn't happen (and I was more interested in
getting things working first), but it turns out that simple getters that
result in a zero adjustment are quite common (70/535 in qwaq-app.dat).
It now takes the function name to print in error message (passed on to
PR_Sprintf) and the argument number of the format string. The variable
arguments (in ...) are assumed to be immediately after the format
argument.
This is actually an old bug in qwaq that was masked by v6p progs
parameter passing: it was just luck that event got put in the correct
parameter and not trampled until the responder saw it. Ruamoko progs,
however, simply lost the event entirely because it never got explicitly
passed by the listener implementation.
This was easy to achieve in v6p progs because all return values passed
through .return and thus could not be lost. However, Ruamoko progs use a
return pointer which can wind up pointed into the void (the return
buffer) and thus cause the return value to be lost. Using @return on
obj_msg_sendv bounces the return pointer through to the called function.
In addition, nil is returned when the forwarding target is nil.
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.
This loads the current return pointer into the specified register. No
offset is used (should make that an error, but for now any offset is
simply ignored). This is part of the fix for getting obj_msg_sendv to
work with return values.
With the return buffer in progs_t, it could not be addressed by the
progs on 64-bit machines (this was intentional, actually), but in order
to get obj_msg_sendv working properly, I needed a way to "bounce" the
return address of a calling function to the called function. The
cleanest solution I could think of was to add a mode to the with
instruction allowing the return pointer to be loaded into a register and
then calling the function with a 0 offset for the return value but using
the relevant register (next few commits). Testing promptly segfaulted
due to the 64-bit offset not fitting into a 32-bit value.
This gets message forwarding apparently working, though something isn't
quite right as qwaq-app doesn't update properly when I try to step
through the program, but that could be an error elsewhere.
The plan is to use the types to extract the number of parameters for a
selector when it is necessary to know the count. However, it'll probably
become useful for something else alter (these things seem to always do
so).
This takes care of the problems with PR_RESET_PARAMS (which has recently
become just a wrapper for PR_SetupParams) changing the stack and causing
PR_CallFunction to save the wrong stack pointer. Message forwarding is
currently broken for Ruamoko ISA progs, but that is due to not having a
valid pr_argc. However, I do have a plan involving extracting the
parameter count from the selector, but that's something for a later
commit. Everything else seems to be ok (my little game is working
nicely).
When doing the builtin params data change, I had somehow switch
multicast's number from 82 to 81. Fortunately, another builtin is also
81, so the VM told me off when I tried to run qw-server :)
rua_obj was skipped because that looks to be a bit more work and should
be a separate commit.
This is to avoid the stack getting mangled when calling progs functions
with parameters.
I suppose having one builtin call another was a neat idea at the time,
and really could have been fixed by simply wrapping the calls with
push/pop frame, but this is probably faster.
obj_msg_sendv needs to push the parameters onto the stack for Ruamoko
progs, but this causes problems because PR_CallFunction winds up
recording the wrong stack pointer for progs functions, and nothing
restores the stack for builtins. The handling is basically the same as
for the return pointer.