commit 5e6f06cf59
Author: Aaron Gutierrez <gutierrez.aaron.m@gmail.com>
Date: Thu May 11 15:42:11 2017 -0400
Fixed issue with aliasing local variables
ISPC++ now produces valid code, or an appropriate error message, for all
of my test cases.
commit bfe723e1b7
Author: Aaron Gutierrez <gutierrez.aaron.m@gmail.com>
Date: Thu May 11 03:09:38 2017 -0400
Actually copy the AST.
Type replacement works except for function parameters.
commit f65b3e6300
Author: Aaron Gutierrez <gutierrez.aaron.m@gmail.com>
Date: Thu May 11 01:19:50 2017 -0400
[WIP] Remove cases for ForeachStmt and SymbolExpr
commit 2e28640860
Merge: 6a91c5dd020107
Author: Aaron Gutierrez <gutierrez.aaron.m@gmail.com>
Date: Wed May 10 23:13:40 2017 -0400
Merge branch 'master' into copy_ast
commit 6a91c5d5ac
Author: Aaron Gutierrez <gutierrez.aaron.m@gmail.com>
Date: Wed May 10 11:11:39 2017 -0400
Attempt to replicate AST when expanding polytypes
We can now do constant folding with all basic datatypes (the previous
implementation handled int32 well, but had limited, if any, coverage
for other datatypes.)
Reduced a bit of repeated code in the constant folding implementation
through template helper functions.
Implicit conversion to function types is now a more standard part of
the type conversion infrastructure, rather than special cases of things
like FunctionSymbolExpr immediately returning a pointer type, etc.
Improved AddressOfExpr::TypeCheck() to actually issue errors in cases
where it's illegal to take the address of an expression.
Added AddressOfExpr::GetConstant() implementation that handles taking
the address of functions.
Issue #223.
We now have separate Expr implementations for dereferencing pointers
and automatically dereferencing references. This is in particular
necessary so that we can detect attempts to dereference references
with the '*' operator in programs and issue an error in that case.
Fixes issue #192.
Now, if a struct member has an explicit 'uniform' or 'varying'
qualifier, then that member has that variability, regardless of
the variability of the struct's variability. Members without
'uniform' or 'varying' have unbound variability, and in turn
inherit the variability of the struct.
As a result of this, now structs can properly be 'varying' by default,
just like all the other types, while still having sensible semantics.
Also reworked TypeCastExpr::GetConstant() to just forward the request along
and moved the code that was previously there to handle uniform->varying
smears of function pointers to FunctionSymbolExpr::GetConstant().
Fixes issue #168.
Now, when a type is declared without an explicit "uniform" or "varying"
qualifier, its variability is unbound; depending on the context of the
declaration, the variability is later finalized.
Currently, in almost all cases, types with unbound variability are
resolved to varying types; the one exception is typecasts like:
"(int)1"; in this case, the fact that (int) has unbound variability
carries through to the TypeCastExpr, which in turn notices that the
expression being type cast has uniform type and in turn will resolve
(int) to (uniform int).
Fixes issue #127.
Previously, they all went into one big pile that was never cleaned up;
this was the wrong thing to do in a world where one might have a
function declaration inside another functions, say.
Allow <, <=, >, >= comparisons of pointers
Allow explicit type-casting of pointers to and from integers
Fix bug in handling expressions of the form "int + ptr" ("ptr + int"
was fine).
Fix a bug in TypeCastExpr where varying -> uniform typecasts
would be allowed (leading to a crash later)
Pointers can be either uniform or varying, and behave correspondingly.
e.g.: "uniform float * varying" is a varying pointer to uniform float
data in memory, and "float * uniform" is a uniform pointer to varying
data in memory. Like other types, pointers are varying by default.
Pointer-based expressions, & and *, sizeof, ->, pointer arithmetic,
and the array/pointer duality all bahave as in C. Array arguments
to functions are converted to pointers, also like C.
There is a built-in NULL for a null pointer value; conversion from
compile-time constant 0 values to NULL still needs to be implemented.
Other changes:
- Syntax for references has been updated to be C++ style; a useful
warning is now issued if the "reference" keyword is used.
- It is now illegal to pass a varying lvalue as a reference parameter
to a function; references are essentially uniform pointers.
This case had previously been handled via special case call by value
return code. That path has been removed, now that varying pointers
are available to handle this use case (and much more).
- Some stdlib routines have been updated to take pointers as
arguments where appropriate (e.g. prefetch and the atomics).
A number of others still need attention.
- All of the examples have been updated
- Many new tests
TODO: documentation
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.
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.
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.
Added AST and Function classes.
Now, we parse the whole file and build up the AST for all of the
functions in the Module before we emit IR for the functions (vs. before,
when we generated IR along the way as we parsed the source file.)
Within each function that launches tasks, we now can easily track which
tasks that function launched, so that the sync at the end of the function
can just sync on the tasks launched by that function (not all tasks
launched by all functions.)
Implementing this led to a rework of the task system API that ispc generates
code to call; the example task systems in examples/tasksys.cpp have been
updated to conform to this API. (The updated API is also documented in
the ispc user's guide.)
As part of this, "launch[n]" syntax was added to launch a number of tasks
in a single launch statement, rather than requiring a loop over 'n' to
launch n tasks.
This commit thus fixes issue #84 (enhancement to launch multiple tasks from
a single launch statement) as well as issue #105 (recursive task launches
were broken).
The intent is that the code in stdlib.ispc that is calling out to the built-ins
should match argument types exactly (using explicit casts as needed), just
for maximal clarity/safety.
Go back to running both sides of 'if' statements with masking and without
branching if we can determine that the code is relatively simple (as per
the simple cost model), and is safe to run even if the mask is 'all off'.
This gives a bit of a performance improvement for some of the examples
(most notably, the ray tracer), and is the code that one wants generated
in this case anyhow.
This is currently only used to decide whether it's worth doing an
"are all lanes running" check at the start of functions--for small
functions, it's not worth the overhead.
The cost is estimated relatively early in compilation (e.g. before
we know if an array access is a scatter/gather or not, before
constant folding, etc.), so there are many known shortcomings.
Fixes issue #73. Previously, if we had e.g. an int16 type that was being shifted
left by 1, then the constant integer 1 would come in as an int32, we'd convert
the int16 to an int32, and then we'd do the shift. Now, for shifts, the type
of the expression is always the same as the type of the value being shifted.
This commit adds support for swizzles like "foo.zy" (if "foo" is,
for example, a float<3> type) as rvalues. (Still need support for
swizzles as lvalues.)