and its usage. The parts of flow_analyze_statement that use it know
where the returned operand needs to go. Unfortunately, this breaks dags
pretty hard, but that's because dags needs to learn about the fancy
assignment-type statements.
I noticed that pointer math is currently incorrect in qfcc, but it would
be nice for fixing it to not break anonstruct since it is testing
something else.
This fixes the technically correct but horrible mess of temps and
addressing when dealing with ivars, and the resulting uninitialized
temps due to the non-constant pointers (do need statement level constant
folding, though).
This is part of what messed up float_val in the encoding for @params.
The other part is something in the linker type encoding merge code: it
may be too aggressive. It's also what messed up the size of @params.
That is, those created by operand_address. The dag code needs the
expression that is attached to the statement to have the correct
expression type in order to do the right thing with the operands and
aliasing, especially when generating temps. This fixes assignchain when
optimizing (all tests pass again).
This reverts commit c78d15b331.
While a block expression's result may be an l-value, block expressions
are not (and their results may not be), thus taking the address of one
is not really correct. It seems the only place that tries to do so is
the assignment code when dealing with structures.
This reverts commit b49d90e769.
I suspect this was a workaround for the mess in assignment chains.
However, it caused compile errors with the new implementation, and is
just bogus anyway.
While I still hate ".=", at least it's more hidden, and the new
implementation is a fair bit cleaner (hah, goto a label in an if (0) {}
block).
Most importantly, the expression tree code knows nothing about it. Now
just to figure out what broke func-epxr. A bit of whack-a-mole, but yay
for automated tests.
Doing it in the expression trees was a big mistake for a several
reasons. For one, expression trees are meant to be target-agnostic, so
they're the wrong place for selecting instruction types. Also, the move
and memset expressions broke "a = b = c;" type expression chains.
This fixes most things (including the assignchain test) with -Werror
turned off (some issues in flow analysis uncovered by the nil
migration: memset target not extracted).
Now convert_nil only assigns the nil expression a type, and nil makes
its way down to the statement emission code (where it belongs, really).
Breaks even more things :)
This bug drove me nuts for several hours until I figured out what was
going on.
The assignment sub-tree is being generated, then lost. It works for
simple assignments because a = b = c -> (= a (= b c)), but for complex
assignments (those that require move or memset), a = b = c -> (b = c) (a
= c) but nothing points to (b = c). The cause is using binary
expressions to store assignments.
It's not possible to take the address of constants (at this stage) and
trying to use a move instruction with .zero as source would result in
the VM complaining about null pointer access when bounds checking is on.
Thus, don't convert a nil source expression until it is known to be
safe, and use memset when it is not.
This fixes the problem of using the return value of a function as an
element in a compound initializer. The cause of the problem is that
compound initializers were represented by block expressions, but
function calls are contained within block expressions, so def
initialization saw the block expression and thought it was a nested
compound initializer.
Technically, it was a bug in the nested element parsing code in that it
wasn't checking the result value of the block expression, but using a
whole new expression type makes things much cleaner and the work done
paves the way for labeled initializers and compound assignments.
Not that it really makes any difference for labels since they're
guaranteed unique, but it does remove the question of "why nva instead
of save_string?". Looking at history, save_string came after I changed
it from strdup (va()) to nva(), and then either didn't think to look for
nva or thought it wasn't worth changing.
Multi-line calls (especially messages) got rather confusing to read as
the lines jumped back and forth. Now the binding is better but the dags
code is reordering the parameters sometimes.
The server code is not yet ready for doubles, especially in its varargs
builtins: they expect only floats. When float promotion is enabled
(default for advanced code, disabled for traditional or v6only),
"@float_promoted@" is written to the prog's strings.
That was a fair bit trickier than I thought, but now .return and .paramN
are handled correctly, too, especially taking call instructions into
account (they can "kill" all 9 defs).
This reverts commit a2f203c840.
There is indeed a world of difference between "any" and "only", and it
helps if I read the rest of the docs AND the code :P.
As expected, this does not fix the mangled pointer problem in
struct-init-param.r, but it does improve the ud-chains. There's still a
problem with .return, but it's handling in flow_analyze_statement is a
bit "special" :P.
Doing the same thing at the end of two branches of an if/else seems off.
And doing an associative(?) set operation every time through a loop is
wasteful.
This fixes the ICE when attempting to compile address-cast without
optimization (just realized why, too: the assignment was optimized out
of existence).
This the fixes the incorrect flow analysis caused by the def being seen
to have the wrong size (structure field of structure def seen through a
constant pointer). Fixes the ICE, but the pointer constant is broken
somewhere in dags, presumably.
This fixes the problem of using nil for two different compound types
within the one expression. The problem is all compound types have the
same low-level type (ev_invalid) and this caused the two different nils
to have the same type when taken back up to expression level.
While expression symbols worked for what they are, they weren't so good
for ivar access because every ivar of a class (and its super classes)
would be accessed at method scope creation, generating spurious access
errors if any were private. That is, when the access checks worked at
all.
The end goal was to fix erroneous non-constant initializer errors for
the following (ie, nested initializer blocks):
typedef struct { int x; int y; } Point;
typedef struct { int width; int height; } Extent;
typedef struct Rect_s { Point offset; Extent extent; } Rect;
Rect makeRect (int xpos, int ypos, int xlen, int ylen)
{
Rect rect = {{xpos, ypos}, {xlen, ylen}};
return rect;
}
However, it turned out that nested initializer blocks for local
variables did not work at all in that the relocations were lost because
fake defs were being created for the generated instructions.
Thus, instead of creating fake defs, simply record the offset relative
to the base def, the type, and the basic type initializer expression,
then generate instructions that all refer to the correct def but with a
relative offset.
Other than using the new element system, static initializers are largely
unaffected.
This is for adding methods to classes and protocols via their interface,
not for adding methods by adding protocols (they still get copied).
Slightly more memory efficient.
Copying methods is done when adding protocols to classes (the current
use for adding regular methods is an incorrect solution to a different
problem). However, when a method is added to a class, the type of its
self parameter is set to be a pointer to the class. Thus, not only does
the method need to be copied, the self parameter does too, otherwise
the self parameter of methods added via protocols will have their type
set to be a pointer to the last class seen adding the protocol.
That is, if, while compiling the implementation for class A, but the
interface for class B is comes after the interface for class A, and both
A and B add protocol P, then all methods in protocol P will have self
pointing to B rather than A.
@protocol P
-method;
@end
@interface A <P>
@end
@interface B <P>
@end
@implementation A
-method {} // self is B, not A!
@end
Duplicate methods in an interface (especially across protocols and
between protocols and the interface) are both harmless and even to be
expected. They certainly should not cause the compiler to demand
duplicate method implementations :)
This is actually a double issue: when a class implementing a protocol
used the protocol in @protocol(), not only would the protocol get
emitted as part of the class data specifying that the class conforms to
the protocol, a second instance would be emitted again when @protocol()
was used. On top of that, only the instance referenced by @protocol()
would be initialized. Now, both class emission and @protocol() get their
protocol def from the same place and thus only one, properly
initialized, protocol instance is emitted.
The problem was an erroneous assumption that the methods had to be
defined. Any class implementing a protocol must implement (and thus
define) the methods, but a protocol declaration cannot: it merely
declares the methods, and it's entirely possible for a module to see
only the protocol definition and not any classes implementing the
protocol.
Unlike gcc, qfcc requires foo to be defined, not just declared (I
suspect this is a bug in gcc, or even the ObjC spec), because allowing
forward declarations causes an empty (no methods) protocol to be
emitted, and then when the protocol is actually defined, one with
methods, resulting in two different versions of the same protocol, which
comments in the gnu objc runtime specifically state is a problem but is
not checked because it "never happens in practice" (found while
investigating gcc's behavior with @protocol and just what some of the
comments about static instance lists meant).
It proved to be too fragile in its current implementation. It broke
pointers to incomplete structs and switch enum checking, and getting it
to work for other things was overly invasive. I still want the encoding,
but need to come up with something more robust.a
This fixes the dependency issues between qwaq and ruamoko. qwaq is
actually older than ruamoko. That little language feature test has come
a long way.
However, I'm considering moving to non-recursive make, but...
It doesn't look good, but it does have panel based windows working, and
using objects. Won't build reliably right now due to qwaq being in tools
and thus building before ruamoko, but I'll fix that next.
It seems that xterm automatically disables it when ncurses shuts down and
mate-terminal does not, or maybe a different version of something. Still,
good to clean up properly.
Now they reflect the curses functions they wrap. The externally visible
builtin names are not changed because the parameters are in x, y order
rather than curses' y, x order.
If the window is invalid and recovery is done, string ids will leak if
acquired before validation.
Afterwards, make the rest of the builtin wrappers consistent: extract
parameters, validate, [acquire resources], generate command.
Now that the initial prototype seems to be working well, it's time to
implement more commands. I might have to do some wrappers for actual
command writing (and result reading) as it looks like there will be a
lot of nearly identical code.
So far, no threading has been set up, and only window creation and
printing have been updated, but the basics of the design seem to be
sound.
The builtin functions now no longer call ncurses directly: the build
commands and write them to a command buffer.
Commands that have return values (eg, window creation) write their
results to a results buffer that the originating builtin function
reads. Builtin functions that expect a result "poll" the results buffer
for the correct result (marked by the same command). In a single
UI-thread environment, the results should always be in the same order as
the commands, and in a multi-UI-thread environment, things should
(fingers crossed) sort themselves out as ONE of the threads will be the
originator of the next available result.
Strings in commands (eg, for printing) are handled by acquiring a string
id (index into an array of dstring_t) and including the string id in the
written command. The string id is released upon completion of the
command.
Builtin functions write commands, acquire string ids, and read results.
The command processor reads commands, releases string ids, and writes
results.
Since commands, string ids, and results are all in ring buffers, and
assuming there is only one thread running the builtin functions and only
one thread processing commands (there can be only one because ncurses is
not thread-safe), then there should never be any contention on the
buffers. Of course, if there are multiple threads running the builtin
functions, then locking will be required on the builtin function side.
I expect I will need several messaging buffers, and ring buffers tend to
be quite robust. Replacing the event buffer code with the macros made
testing easy.
id and z seem to always be 0.
Ironically, it turns out that the work needed for "int id" and "large"
struct nil init wasn't strictly necessary to get to this point, but
without having done that work, I wouldn't know :)
Such declarations were being lost, thus in the following, the id field
never got added:
typedef struct qwaq_mevent_s {
int id;
int x, y, z;
int buttons;
} qwaq_mevent_t;
typedef is meant to create a simple renaming of a potentially complex
type, not create a new type. Keeping the parameter type alias info makes
the types effectively different when it comes to overloaded function
resolution, which is quite contrary to the goal. Does expose some
breakage elsewhere, though.
For technical reasons (programmer laziness), qfcc does not fix up local
def type encodings when writing the debug symbols file (type encoding
location not readily accessible).
The debug subsystem now uses the resources system to ensure it cleans
up, and its data is now semi-private. Unfortunately, PR_LoadDebug had to
remain public for qfprogs because using PR_RunLoadFuncs would cause
builtin resolution to complain.
It is now set to 0 when progs are loaded and every time
PR_ExecuteProgram() returns. This takes care of the default case, but
when setting parameters, pr_argc needs to be set correctly in case a
vararg function is called.
Attempting to define a variable with an incomplete type is an error, and
results in a default size 1 of allocated, but I forgot to set default
alignment when implementing alignment.
The addition of xdef data has made qfo_to_progs unusable in qfprogs,
resulting in various invalid memory accesses. It always was an ugly hack
anyway, so this is the first step to proper qfo support in qfprogs.
I was originally going to put it in the debug syms file, but I realized
that the data persistence code would need access to both def type and
certainly correct def offsets for defs in far data.
This far better reflects the actual meaning. It is very likely that
ty_none is a holdover from long before there was full type encoding and
it meant that the union in qfcc's type_t had no data. This is still
true for basic types, but only if not a function, field or pointer type.
If the type was function, field or pointer, it was not true, so it was
misnamed pretty much from the start.
It was long wrong anyway as it checked past the end of the function's
parameters, which caused a segfault when calling varargs functions with
no formal parameters.
The encoding is 3:5 giving 3 bits for alignment (log2) and 5 bits for
size, with alignment in the 3 most significant bits. This keeps the
format backwards compatible as until doubles were added, all types were
aligned to 1 word which gets encoded as 0, and the size is unaffected.
This fixed the uninitialized temp warning in HUD.r. The problem was
caused by the flow analyzer not being able to detect that the struct
temp was being initialized by the move statement due to the address of
the temp being in a pointer temp. While it would be good to use a
constant pointer for the address of the struct temp or improving the
flow analyzer to track actual data, avoiding the temp in the first place
results in nicer code as it removes a move statement.
With this, cast address initializers work. I have to wonder if the alias
value short-circuit was legacy from long before the rewrite, as it was
quite trivial to handle in the back-end.
All functions are stored in the overload functions table, even those
that are never explicitly overloaded, but only explicitly overloaded
functions (those with @overload) use the type-qualified naming.
Only as scalars, I still need to think about what to do for vectors and
quaternions due to param size issues. Also, doubles are not yet
guaranteed to be correctly aligned.
I plan on adding doubles, and so it's necessary to ensure that attempts
to align doubles in local or far data spaces remain aligned after final
linking.
I added Sys_RegisterShutdown years ago and never really did anything
with it: now any system that needs to be shutdown can ensure it gets
shutdown on program exit, and in the correct order (ie, reverse to init
order).
In order to keep enumerator type and enum type the same, the values need
to have their type set after the enum type is finalized, and then the
appropriate symbols created in the parent scope. This fixes the infinite
recursion when assigning an enum value to its own type.
It turns out the enumerator type and enum type wind up with different
instances of the same type (due to the way type chaining works). This
results in infinite recursion in assign_expr and check_types_compatible.
This is where constant folding should have happened all along. While
unary_expr should fold constants too, it seems to already try to do so
and it's a bit much of a mess to clean up right now.
This is for modern code. Traditional code still treats initialized
globals as constant and nosave. This will make a bit of a mess of
modern code that expects traditional behavior.
While this does break automatic type promotion, it does stop
fold_constants recursing through complex expressions: only the top level
expression needs to be folded, and then only if both sides are actually
constant.
Not sure just what version of automake broke things, but I do remember
having a bad time getting the dependencies to work in the first place.
At least now they should be more reliable (until automake changes
things).
I don't remember what the goal was (stopped working on it eight months
ago), but some possibilities include:
- better handling of nil (have trouble with assigning into struts)
- automatic forward declarations ala C# and jai (I was watching vids
about jai at the time)
- something for pascal
- simply that the default symbol type should not be var (in which case,
goal accomplished)
After messing with SIMD stuff for a little, I think I now understand why
the industry went with xyzw instead of the mathematical wxyz. Anyway, this
will make for less pain in the future (assuming I got everything).
I've decided that setting pr.max_edicts and pr.zone_size as part of the
local progs initialization rather than in PR_LoadProgsFile makes more
sense. For one, it is unlikely for the limits to change every time progs is
reloaded. Also, they seem to be a property of the VM rather than the progs.
However, there is nothing stopping the caller from updating max_edicts and
zone_size every call.
It seems gcc doesn't care if the & is present when calculating field
offsets, but it not being there bothered me very much and might as well use
our "standard" macro anyway.
While scan-build wasn't what I was looking for, it has proven useful
anyway: many of the sizeof errors were just noise, but a few were actual
bugs (allocating too much or too little memory).
If the kahan triangle area method breaks, I did something wrong with qfcc's
handling of parentheses (ie, floating point math is not truly associative).
This fixes a segfault when optimizing the empty-body test. The label was
getting moved, but the statement block to which it pointed was not updated
and thus it pointed to dead data.
It returns the rest of the line (minus // style comments) as the token. I
needed it in another project but this is my central repository for
script.py.
Saw a discussion of such in #qc and that gcc implemented it. I realized it
would be pretty easy to detect and very useful (I've made such mistakes at
times).
It is now in its own file and uses table lookups to check for valid type
and operator combinations, and also the resulting type of the expression.
This probably breaks multiple function calls in the one expression.
This is a bit of a workaround to ensure the operands have their types
setup correctly. Really, binary_expr needs to handle expression types
properly.
This fixes the bogus error for comparing the result of pointer subtraction
with an integer.
Currently, they can represent either vectors or quaternions, and the
quaternions can be in either [s, v] form or [w, x, y, z] form.
Many things will not actual work yet as the vector expression needs to be
converted into the appropriate form for assigning the elements to the
components of the "vector" type.
It's sometimes more useful to have direct access to each individual
component of the imaginary part of the quaternion, and then for
consistency, alias w and s.
This is a nice feature found in fteqcc (also a bit of a challenge from
Spike). Getting bison to accept the new expression required rewriting the
state expression grammar, so this is mostly for the state expression. A
test to ensure the state expression doesn't break is included.
I think it may have been for compatibility with a certain qcc variant (no
idea which one, though). While the shift/reduce conflict is fixable using
"%prec IFX" on the const:string rule, the colon breaks test?"a":"b".
Putting parentheses around "a" allows such a construct, requiring them
breaks comatibility with C. I think this feature just isn't worth that.
This goes towards complementing the "if not" logic extension. I need to
check if fteqcc supports "not" with "while" (the version I have access to
at the moment does not), and also whether it would be good to support
"not" with "for", and if so, what form the syntax should take.
It is syntactic sugar for if (!(foo)), but is useful for avoiding
inconsistencies between such things as if (string) and if (!string), even
though qcc can't parse if not (string). It also makes for easier to read
code when the logic in the condition is complex.
It turns out this is required for compatibility with qcc (and C, really).
Once string to boolean conversions are sorted out completely (not that
simple as qcc is inconsistent with if (string) vs if (!string)), Qgets can
be implemented :)
It looks like I had forgotten that the compare function is supposed to
return true/false (unlike memcmp's sorting ability). Also, avoid the
pointers in the value struct as they can change without notice.
Using enums in switches now works nicely, including warnings for unused
enum values.
Either I had gotten confused while writing the code and mixed up line and
offset, or I had changed offset to line at one stage but missed a place.
This fixes the segfault when compiling chewed-alias.r and return-ivar.r
For the most part, it's just refactoring the code so the plane creation and
testing are in separate functions, but there is one important difference:
the plane test now checks only the two points on either side of the point
used to create the plane.
Because the portal winding is guaranteed to be convex and planar, if both
points are on the plane, all points are, and if neither point is behind the
plane, no points are.a
This shaved about 5 seconds off the level 4 run using 4 threads (~198s to
~193s) and about 12s from the single threaded run (~682s to ~670s (hmm,
gained some time in recent changes)).
qsort is used to sort the queue by nummightsee. At ~4ms for 20k portals, I
think it's affordable. Using a queue rather than scanning the portal list
each time loses the dynamic sorting when mightsee gets updated, but it
seemed to shave off 4s anyway (~207s to ~203s (maybe, yay random times)).
Another step towards threaded base-vis.
This reverts commit 1ea79e8626.
Conflicts:
tools/qfvis/include/vis.h
tools/qfvis/source/flow.c
I've decided to do reentrant versions of the set allocators and I didn't
particularly like the invasiveness of allocating sets this way.
The old variable names were confusing ("target" winding comes from
"portal"?), and the comments were from when I really didn't understand
concepts like separating planes. While they weren't wrong, they were quite
inadequate and I want to write new ones.
This bypasses set_new, but completely removes the use of the global lock
from within RecursiveClusterFlow. This seems to give a small speedup: 203
seconds threaded.
This was testing an idea I had to remove the plane flips. It seems to have
been good for the initial plane orientation, but was a slight slowdown for
the pass-portal test. However, this makes the code a little easier to work
with for my idea on improving the algorithm itself.
Since the stack structure in the thread data is a linked list, move the
stack blocks off the program stack and into malloced memory. More
importantly, when the stack block is allocated, the mightsee working set is
allocated too, and as neither are freed, this greatly reduces contention
for the lock. Also, because the memory is kept, single threaded time for
gmsp3v2 dropped from 695s to 670s. Threaded is now about 207s (down from
350).
While using set operators was clearer, it was rather expensive (about 25s
for gmsp3v2). qfvis now completes the map in about 695s (single threaded).
About 15s faster than tyr for the same conditions (1 thread, level 4).
This is the second part of the separator search optimization from tyrutils
vis. With this, qfvis is getting close to tyrutils vis when
running single threaded (qfvis is suffering some nasty thread contention
and thus can't get below about 350 seconds with 4 threads). 808s vs 707s.
Interesting, it makes very little (maybe faster) difference to find all the
separators for levels 3 and 4. This might be due to the higher levels using
most of the planes to fully clip source away. Anyway, it makes the code a
little clearer (one function, one task).
I had forgotten to skip the refined tests when the sphere was entirely on
the relevant side of the plane. Now BasePortalVis for gmsp3v2 takes 11s on
my machine (it was 13 with the previous optimization and 15.9 before that).
Also, write some comments describing how BasePortalVis works.
Representing the side of the plane on which the sphere lies is much more
useful as more complicated tests can be done using just the one call.
-1: the sphere is entirely on the back side of the plane
0: the sphere is intersecting the plane
1: the sphere is entirely on the front side of the plane
It was supposed to be 2, but for some reason I neglected to set it when I
set up the options parsing. However, level 4 is the standard for production
maps, and it happens to be faster than level 2 (at least for gmsp3v2.bsp)
I think the reason I didn't think of that when I tried to improve qfvis's
performance many years ago is I just simply did not understand
ClipToSeparators. However, the difference caching the separators makes is
phenomenal. Before the change, single threaded qfvis would get stuck on one
particular portal for at least a day (I gave up waiting), but now even a
debug build will complete gmsp3v2.bsp in less than 12 minutes (4 threads on
my quad-core). And that's at level 2! Getting stuck for a day was at level
0.
Rather than prefixing free_ to the supplied name, suffix _freelist to the
supplied name. The biggest advantage of this is it allows the free-list to
be a structure member. It also cleans up the name-space a little.
While noticeably slower than the previous expanded set manipulation code,
this is much easier to read. I can worry about optimizing the set code when
I get qfvis behaving better.
I'd forgotten that ED_ConvertToPlist mangled light into light_lev and
single component angle values into a vector. This fixes much of the
breakage in qflight (but not the light levels)
This removes a lot of redundant code from qflight (though it does become
dependent of libQFgamecode *shrug*). The nice thing is qflight now uses the
exact same code to load entities as does the server.
Something is funny with Ubuntu such that -ldl needs to be specifically
added even though QFutil's .la specifies it. I don't know if it's a libtool
issue or not, but this does work.
More will probably be necessary, but this was sufficient to get prover to
the point where qfcc segged building qwaq (0.7.2).
type_obj_class is no longer a class, so its ivars are not stored in
type_obj_class.t.class->ivars but rather type_obj_class.t.symtab.
This fixes the segfault Spirit and Randy were experiencing.
In passing, correct the unneeded emission of meta class ivars for non-root
classes. This should make for much smaller progs that use classes.
MOVEP's opc itself is always known and used, whether it's a constant
pointer or variable doesn't matter. This fixes the lost pointer calculation
for va_list.list[j] = object_from_plist (item);
Dead nodes are those that generate unused values (unassigned leaf nodes,
expressions or destinationless move(p) nodes). The revoval is done by the
flow analysis code (via the dags code) so that any pre and post removal
flow analysis and manipulation may be done (eg, available expressions).
assign_expr mangles the destination expression for dereferenced
assignments into something that is invalid as an lvalue, so simply use
new_binary_expr with the same opcode.
It turns out expression trees are (mostly?) valid DAGs, so all edges being
constrained works, though the graphs get a little tall (but easier to read).
This fixes the infinite loop in if ((x = self.heat && x))
Really, I think I need to revisit the whole expression tree code. It's
proving to be rather fragile.
The source of the assignment is used as the value to test, and the
assignment itself is inserted into the boolean expressions's block. This
fixes the inernal error for "if ((x = 0))".
Normally, it will happen only as a follow-on error, but I can think of a
way to force it without other errors, so treating it as an internal error
is a bit harsh.
But reset current_symtab to its prior value when done. This fixes a
segfault caused by initializing the class system while parsing a struct
(eg, one of the members is of type id).
The keywords table was rather awkward to edit (and sometimes confusing).
Worse, because the hash table used to look up the keywords was initialized
only once, changing modes in the same execution of qfcc would not work
properly as keywords would not be added or removed as appropriate.
Now there are four categories of keywords:
o "core" Always available. They form the core of QuakeC except for two
extensions.
o "@" In extended and advanced modes, the preceeding @ is optional,
but tranditional mode requires the keywords to be preceeded by
an @. They are the C keywords that QuakeC did not use, but can
be implemented in v6 progs under certain circumstances.
o "QF" These keywords require the QuakeForge VM to be usable.
o "Obj" These keywords form Ruamoko/Objective-QuakeC and require both
advanced mode and the QuakeForge VM.
This fixes the segfault/null pointer access in sendv.r. While I wanted to
use the edge setting code to set the live bit, I didn't expect it to be
this easy. def_visit_all is proving to be worth every bit it consumes :)
It seems dag_set_live_vars still served a purpose after all, but I don't
feel like bringing it as I'd rather implement its param handing in
dagnode_set_edges. I've now got a test case for it, though the test
currently causes the VM to segfault (even with pr_boundscheck 2!).
If the final block ends in a conditional statement, appending return to the
block will hide the conditional statement from the flow analyzer. This may
cause the conditional statement's destination node be become unreachable
according to the analyzer and thus eliminated. The label for the branch
then loses its target sblock and thus the code generator will produce a
zero-distance jump resulting in an infinite loop.
Thus, if the final block ends in a conditional statement (or, for
completeness, a call statement), append a new empty block before adding the
return statement.
If MOVEP's destination is variable, then the actual destination isn't (at
this stage) knowable, so it can't be attached to the dagnode and thus must
be a child.
Getting the operands directly from the statement was missing the
destination operand of movep when movep's op_c was a constant pointer and
thus the flowvar wasn't being counted/created early enough. This led to a
segfault in the set code when attempting to add -1 to the set.
It turns out the recent dead-block code "broke" vector component access
from objects. The breakage is really highlighting a problem with temporary
operands and aliasing. The problem was hiding behind a basic-block split
that the recent dead-block work mended and thus exposed the bug.
type_id is implemented as a pointer to "struct obj_object" (ie, not really
a class), so the correct check is to ensure the type is:
1 a pointer
2 to a struct
3 using the same symbol table as type_obj_object
