Added support for resolving dimensions of multi-dimensional unsized arrays
from their initializer exprerssions (previously, only the first dimension
would be resolved.)
Added checks to make sure that no unsized array dimensions remain after
doing this (except for the first dimensision of array parameters to
functions.)
Substantial improvements and generalizations to the parsing and
declaration handling code to properly parse declarations involving
pointers. (No change to user-visible functionality, but this
lays groundwork for supporting a more general pointer model.)
Previously, to compute the size of objects and the offsets of struct
elements within structs, we were using the trick of using getelementpointer
with a NULL base pointer and then casting the result to an int32/64.
However, since we actually know the target we're compiling for at
compile time, we can use corresponding methods from TargetData to
get these values directly.
This mostly cleans up code, but may make some of the gather/scatter
lowering to loads/stores optimizations work better in the presence
of structures.
Now, the Linker::LinkModules() call doesn't link in any functions
marked as 'internal', which is problematic, since we'd like to have
just about all of the builtins marked as internal so that they are
eliminated after they've been inlined when they are in fact used.
This change removes all of the internal qualifiers in the builtins
and adds a lSetInternalFunctions() routine to builtins.cpp that
sets this property on the functions that need it after they've
been linked in by LinkModules().
Both uniform and varying function pointers are supported; when a function
is called through a varying function pointer, each unique function pointer
value across the running program instances is called once for the set of
active program instances that want to call it.
Be better about tracking the full extent of expressions in the parser;
this leads to more intelligible error messages when we indicate where
exactly the error happened.
Previously, it was only in the GatherScatterFlattenOpt optimization pass that
we added the per-lane offsets when we were indexing into varying data.
(Specifically, the case of float foo[]; int index; foo[index], where foo
is an array of varying elements rather than uniform elements.) Now, this
is done in the front-end as we're first emitting code.
In addition to the basic ugliness of doing this in an optimization pass,
it was also error-prone to do it there, since we no longer have access
to all of the type information that's around in the front-end.
No functionality or performance change.
The Expr::TypeConv() method has been replaced with both a
CanConvertTypes() routine that indicates whether one type
can be converted to another and a TypeConvertExpr()
routine that provides the same functionality as
Expr::TypeConv() used to.
This code previously lived in FunctionCallExpr but is now part
of FunctionSymbolExpr. This change doesn't change any current
functionality, but lays groundwork for function pointers in
the language, where we'll want to do function call overload
resolution at other times besides when a function call is
actually being made.
The stuff in decl.h/decl.cpp is messy, largely due to its close mapping
to C-style variable declarations. This checkin has updated code throughout
all of the declaration statement, variable, and function code that operates
on symbols and types directly. Thus, Decl* related stuff is now localized
to decl.h/decl.cpp and the parser.
Issue #13.
Specifically, we had been using the full mask for all gathers, rather than
using the internal mask when we were loading from locally-declared arrays.
Thus, given code like:
uniform float x[programCount] = { .. . };
float xx = x[programIndex];
Previously we weren't generating a plain vector load to initialize xx, when
this code was in a function where it wasn't known that the mask was all on,
even though it should have. Now it does.
It's not clear that these are actually all that helpful.
This also works around issue #89, wherein code like "int8 = 0" would
give a warning about conversion from int32 to int8.
Generalize the overload resolution code to be based on estimating a
cost for various overload options and picking the one with the
minimal cost.
Add a step that considers type conversions that are guaranteed to
not lose information in function overload resolution.
Print better diagnostics when we can't find an unambiguous match.
In particular, this fixes issue #81, where a global variable access was leading to
ConstantExpressions showing up in this code, which it wasn't previously expecting.
Specifically, now we can work through phi nodes in the IR to detect cases
where an index value is actually the same across lanes or is linear across
the lanes. For example, this is a loop that used to require gathers but
is now turned into vector loads:
for (int i = programIndex; i < 16; i += programCount)
sum += a[i];
Fixes issue #107.
