This patch allows optimizing redundant array repacking, when
the source array is statically known to be contiguous.
This is part of the implementation plan for the array repacking
feature, though, it does not affect any real life use case
as long as FIR inlining is not a thing. I experimented with
simple cases of FIR inling using `-inline-all`, and I recorded
these cases in optimize-array-repacking.fir tests.
This patch updates several passes to include the DLTI dialect, since
their use of the `fir::support::getOrSetMLIRDataLayout()` utility
function could, in some cases, require this dialect to be loaded in
advance.
Also, the `CUFComputeSharedMemoryOffsetsAndSize` pass has been updated
with a dependency to the GPU dialect, as its invocation to
`cuf::getOrCreateGPUModule()` would result in the same kind of error if
no other operations or attributes from that dialect were present in the
input MLIR module.
This change allows marking more designators producing an opaque
box with 'contiguous' attribute, e.g. like in test1 case
in flang/test/HLFIR/propagate-contiguous-attribute.fir.
This would make isSimplyContiguous() return true for such
designators allowing merging hlfir.eval_in_mem with hlfir.assign
where the LHS is a contiguous array section.
Depends on #139003
This change enables LoopVersioning when `fir.pack_array` is met
in the def-use chain. It fixes a couple of huge performance regressions
caused by enabling `-frepack-arrays`.
Move non-common files from FortranCommon to FortranSupport (analogous to
LLVMSupport) such that
* declarations and definitions that are only used by the Flang compiler,
but not by the runtime, are moved to FortranSupport
* declarations and definitions that are used by both ("common"), the
compiler and the runtime, remain in FortranCommon
* generic STL-like/ADT/utility classes and algorithms remain in
FortranCommon
This allows a for cleaner separation between compiler and runtime
components, which are compiled differently. For instance, runtime
sources must not use STL's `<optional>` which causes problems with CUDA
support. Instead, the surrogate header `flang/Common/optional.h` must be
used. This PR fixes this for `fast-int-sel.h`.
Declarations in include/Runtime are also used by both, but are
header-only. `ISO_Fortran_binding_wrapper.h`, a header used by compiler
and runtime, is also moved into FortranCommon.
As there is now certain areas where we now have the possibility of
having either a ModuleOp or GPUModuleOp and both of these modules can
have DataLayout's and we may require utilising the DataLayout utilities
in these areas I've taken the liberty of trying to extend them for use
with both.
Those with more knowledge of how they wish the GPUModuleOp's to interact
with their parent ModuleOp's DataLayout may have further alterations
they wish to make in the future, but for the moment, it'll simply
utilise the basic data layout construction which I believe combines
parent and child datalayouts from the ModuleOp and GPUModuleOp. If there
is no GPUModuleOp DataLayout it should default to the parent ModuleOp.
It's worth noting there is some weirdness if you have two module
operations defining builtin dialect DataLayout Entries, it appears the
combinatorial functionality for DataLayouts doesn't support the merging
of these.
This behaviour is useful for areas like:
https://github.com/llvm/llvm-project/pull/119585/files#diff-19fc4bcb38829d085e25d601d344bbd85bf7ef749ca359e348f4a7c750eae89dR1412
where we have a crossroads between the two different module operations.
Loops resulting from array expressions like array(:,i)
may be versioned for the unit stride of the innermost dimension,
when the initial array is an assumed-shape array (which are contiguous
in many Fortran programs).
This speeds up facerec for about 12% due to further vectorization
of the innermost loop produced for the total SUM reduction.
This PR adds initial debug support for derived type. It handles
`RecordType` and generates appropriate `DICompositeTypeAttr`. The
`TypeInfoOp` is used to get information about the parent and location of
the derived type.
We use `getTypeSizeAndAlignment` to get the size and alignment of the
components of the derived types. This function needed a few changes to
be suitable to be used here:
1. The `getTypeSizeAndAlignment` errored out on unsupported type which
would not work with incremental way we are building debug support. A new
variant of this function has been that returns an std::optional. The original
function has been renamed to `getTypeSizeAndAlignmentOrCrash` as it
will call `TODO()` for unsupported types.
2. The Character type was returning size of just element and not the
whole string which has been fixed.
The testcase checks for offsets of the components which had to be
hardcoded in the test. So the testcase is currently enabled on x86_64.
With this PR in place, this is how the debugging of derived types look
like:
```
type :: t_date
integer :: year, month, day
end type
type :: t_address
integer :: house_number
end type
type, extends(t_address) :: t_person
character(len=20) name
end type
type, extends(t_person) :: t_employee
type(t_date) :: hired_date
real :: monthly_salary
end type
type(t_employee) :: employee
(gdb) p employee
$1 = ( t_person = ( t_address = ( house_number = 1 ), name = 'John', ' ' <repeats 16 times> ), hired_date = ( year = 2020, month = 1, day = 20 ), monthly_salary = 3.1400001 )
```
…ted. (#89998)" (#90250)
This partially reverts commit 7aedd7dc754c74a49fe84ed2640e269c25414087.
This change removes calls to the deprecated member functions. It does
not mark the functions deprecated yet and does not disable the
deprecation warning in TypeSwitch. This seems to cause problems with
MSVC.
The pass is currently defined as only considering function arguments as
candidates for the optimization. I would prefer to generalise the pass
for other top level operations only when there is a concrete use case
before making too many assumptions about the current set of top level
operations. Therefore I have not adapted this pass to run on all top
level operations.
The existing type size computation in LoopVersioning does not work
for REAL*10, because the compute element size is 10 bytes,
which violates the power-of-two assertion.
We'd better use the DataLayout for computing the storage size
of each element of an array of the given type.
The added test case has a loop that is versioned, which has a use of the
loop in an if block after the loop. The current code replaces all uses
of the loop with the new version If, but only if the parent blocks
match. As far as I can see it should be safe to replace all the uses,
then construct the result for the If with op.op.
This avoids trying to version loops that can't be versioned, and thus
avoids hitting an assert.
Co-authored with Slava Zakharin (who provided the test-code).
The first test case added in the LIT test demonstrates the problem.
Even though we did not consider the inner loop as a candidate for
the transformation due to the array_coor with a slice, we decided to
version the outer loop for the same function argument.
During the cloning of the outer loop we dropped the slicing completely
producing invalid code.
I restructured the code so that we record all arg uses that cannot be
transformed (regardless of the reason), and then fixup the usage
information across the loop nests. I also noticed that we may generate
redundant contiguity checks for the inner loops, so I fixed it
since it was easy with the new way of keeping the usage data.
This is the last piece required for the loop versioning patch to work on
code lowered via HLFIR. With this patch, HLFIR performance on spec2017
roms is now similar to the FIR lowering.
Adding support for fir.array_coor means that many more loops will be
versioned, even in the FIR lowering. So far as I have seen, these do not
seem to have an impact on performance for the benchmarks I tried, but I
expect it would speed up some programs, if the loop being versioned
happened to be the hot code.
The main difference between fir.array_coor and fir.coordinate_of is
that fir.coordinate_of uses zero-based indices, whereas fir.array_coor
uses the indices as specified in the Fortran program (starting from 1 by
default, but also supporting non default lower bounds). I opted to
transform fir.array_coor operations into fir.coordinate_of operations
because this allows both to share the same offset calculation logic.
The tricky bit of this patch is getting the correct lower bounds for the
array operand to subtract from the fir.array_coor indices to get a
zero-based indices. So far as I can tell, the FIR lowering will always
provide lower bounds (shift) information in the shape operand to the
fir.array_coor when non-default lower bounds are used. If none is given,
I originally tried falling back to reading lower bounds from the box,
but this led to misscompilation in SPEC2017 cam4. Therefore the pass
instead assumes that if it can't already find an SSA value for the shift
information, the default lower bound (1) should be used.
A suspect the incorrect lower bounds in the box for the FIR lowering was
already a known issue (see https://reviews.llvm.org/D158119).
Differential Revision: https://reviews.llvm.org/D158597
This patch fixes multiple tests failing with segfault due to accessing
absent argument box before the loop versioning check.
The absent arguments might be treated as contiguous for the purpose
of loop versioning, but this is not done in this patch.
Reviewed By: PeteSteinfeld
Differential Revision: https://reviews.llvm.org/D158800
Since https://reviews.llvm.org/D158119, many boxes lowered via HLFIR are
reboxed with better lower bounds information after they are declared.
For the loop versioning pass to support FIR lowered via HLFIR, it needs
to dereference fir.rebox operations to figure out that the variable was
a function argument.
I decided to modify the existing dereferencing of fir.declare so that
the declared/reboxed value is used in the versioned loop instead of the
function argument. This makes it easier for the improved lower bounds
information to be accessed. In doing this, I changed ArgInfo to store
ArgInfo::arg by value instead of by pointer because mlir::Value has
value-type semantics.
Differential Revision: https://reviews.llvm.org/D158408
When FIR comes from HLFIR, there will be a fir.declare operation between
the source and the usage of each source variable (and some temporary
allocations). This pass needs to be able to follow these so that it can
still transform loops when HLFIR is used, otherwise it mistakenly
assumes these values are not function arguments.
More work is needed after this patch to fully support HLFIR, because the
generated code tends to use fir.array_coor instead of fir.coordinate_of.
Differential Revision: https://reviews.llvm.org/D157964
Previously only a constant reference was stored in the FirOpBuilder.
However, a lot of code was merged using
FirOpBuilder builder{rewriter, getKindMapping(mod)};
This is incorrect because the KindMapping returned will go out of scope
as soon as FirOpBuilder's constructor had run. This led to an infinite
loop running some tests using HLFIR (because the stack space containing
the kind mapping was re-used and corrupted).
One solution would have just been to fix the incorrect call sites,
however, as a large number of these had already made it past review, I
decided to instead change FirOpBuilder to store its own copy of the
KindMapping. This is not costly because nearly every time we construct a
KindMapping is exclusively to construct a FirOpBuilder. To make this
common pattern simpler, I added a new constructor to FirOpBuilder which
calls getKindMapping().
Differential Revision: https://reviews.llvm.org/D151881
Despite me being convinced that the use of divide didn't produce any
divide instructions, it does in fact add more instructions than using
a plain shift operation.
This patch simply changes the divide to a shift right, with an
assert to check that the "divisor" is a power of two.
Reviewed By: kiranchandramohan, tblah
Differential Revision: https://reviews.llvm.org/D151880
This patch makes more than 2D arrays work, with a fix for the way that
loop index is calculated. Removing the restriction of number of
dimensions.
This also changes the way that the actual index is calculated, such that
the stride is used rather than the extent of the previous dimension. Some
tests failed without fixing this - this was likely a latent bug in the
2D version too, but found in a test using 3D arrays, so wouldn't
have been found with 2D only. This introduces a division on the index
calculation - however it should be a nice and constant value allowing
a shift to be used to actually divide - or otherwise removed by using
other methods to calculate the result. In analysing code generated with
optimisation at -O3, there are no divides produced.
Some minor refactoring to avoid repeatedly asking for the "rank" of the
array being worked on.
This improves some of the SPEC-2017 ROMS code, in the same way as the
limited 2D array improvements - less overhead spent calculating array
indices in the inner-most loop and better use of vector-instructions.
Reviewed By: kiranchandramohan
Differential Revision: https://reviews.llvm.org/D151140
Introduce conditional code to identify stride of "one element", and simplify the array accesses for that case.
This allows better loop performance in various benchmarks.
Reviewed By: tblah, kiranchandramohan
Differential Revision: https://reviews.llvm.org/D141306
