Patch 2/3 of the transition step 1 described in
https://discourse.llvm.org/t/rfc-enabling-the-hlfir-lowering-by-default/72778/7.
All the modified tests are still here since coverage for the direct
lowering to FIR was still needed while it was default. Some already have
an HLFIR version, some have not and will need to be ported in step 2
described in the RFC.
Note that another 147 lit tests use -emit-fir/-emit-llvm outputs but do
not need a flag since the HLFIR/no HLFIR output is the same for what is
being tested.
Change the separator in the `uniqueCGIdent` method to `X`. This change
is required to enable OpenMP offloading for the NVPTX target, as dots
are not valid identifiers in PTX and `uniqueCGIdent` is used to mangle
some literals. Follow up patches will change the remainder of `.`
appearances in names to `X` and add support for the NVPTX target.
Fixes https://github.com/llvm/llvm-project/issues/67658
The bug was that when instantiating a character array result variable,
the code inserted a cast from the result buffer to the proper array type
if it could see an fir.unboxchar op. But this is wrong for results and
on caller side because the fir.emboxchar is visible so,
charHelper.genUnboxChar() just takes the operand from that instead of
generating an unboxchar.
The fix is simply to move the cast at the place where fir.boxchar<>
argument are dealt with. The cast when creating fir.emboxchar is also
removed: it adds noise and causes constant length result type to be
lowered to fir.char<?>.
The main change from this patch is to deal with the lit test fallout of
this cast move and removal.
On platforms which support COMDAT sections we should use them when
linkonce or linkonce_odr linkage is requested. This is required on
Windows (PE/COFF) and provides better behaviour than weak symbols on
ELF-based platforms.
This patch also reverts string literals to use linkonce instead of
internal linkage now that comdats are supported.
Differential Revision: https://reviews.llvm.org/D153768
On Windows, global string literals with "linkonce" linkage is not
supported without using comdat. As a simpler fix than adding comdat
support we can use internal linkage instead.
This fixes a bug where two string literals with the same value in
different fortran files would cause a linker error due to the use
of linkonce linkage.
Reviewed By: jeanPerier
Differential Revision: https://reviews.llvm.org/D149859
Currently, local allocatables and contiguous/scalar pointers (and some
other conditions) are lowered to a set of independent variables in FIR
(one for the address, one for each bound and one for character length).
The intention was to help LLVM get rids of descriptors. But LLVM knows
how to do that anyway in those cases:
```
subroutine foo(x)
real, target :: x(100)
real, pointer, contiguous :: p(:)
p => x
call bar(p(50))
end subroutine
```
The output fir the option on or off is the same after llvm opt -O1,
there is no descriptor anymore, the indirection is removed.
```
define void @foo_(ptr %0) local_unnamed_addr {
%2 = getelementptr [100 x float], ptr %0, i64 0, i64 49
tail call void @bar_(ptr %2)
ret void
}
```
So the benefit of not using a descriptor in lowering is questionable,
and although it is abstracted as much as possible in the so called
MutableBoxValue class that represent allocatable/pointer in lowering
it is still causing bugs from time to time, and will also be a bit
problematic when emitting debug info for the pointer/allocatable.
In HLFIR lowering, the simplification to always use a descriptor in
lowering was already made. This patch allows decorrelating the impact
from this change from the bigger impact HLFIR will have so that it
is easier to get feedback if this causes performance issues.
The lowering tests relying on the previous behavior are only updated
to set back this option to true. The reason is that I think we should
preserve coverage of the code dealing with the "non descriptor" approach
in lowering until we actually get rid of it. The other reason is that
the test will have to be or are already covered by equivalent HLFIR
tests, which use descriptors.
Differential Revision: https://reviews.llvm.org/D148910
Following RFC at
https://discourse.llvm.org/t/rfc-ffp-contract-default-value/66301
This adds the `fastmath<contract>` attribute to `fir.call` and some
floating point arithmetic operations (hence the many test changes).
Instead of testing for this specific attribute, I am using a regular
expression to match any attributes.
Array-value-copy fails to generate a temporary array for case like this:
subroutine bug(b)
real, allocatable :: b(:)
b = b(2:1:-1)
end subroutine
Since LHS may need to be reallocated, lowering produces the following FIR:
%rhs_load = fir.array_load %b %slice
%lhs_mem = fir.if %b_is_allocated_with_right_shape {
fir.result %b
} else {
%new_storage = fir.allocmem %rhs_shape
fir.result %new_storage
}
%lhs = fir.array_load %lhs_mem
%loop = fir.do_loop {
....
}
fir.array_merge_store %lhs, %loop to %lhs_mem
// deallocate old storage if reallocation occured,
// and update b descriptor if needed.
Since %b in array_load and %lhs_mem in array_merge_store are not the same SSA
values, array-value-copy does not detect the conflict and does not produce
a temporary array. This causes incorrect result in runtime.
The suggested change in lowering is to generate this:
%rhs_load = fir.array_load %b %slice
%lhs_mem = fir.if %b_is_allocated_with_right_shape {
%lhs = fir.array_load %b
%loop = fir.do_loop {
....
}
fir.array_merge_store %lhs, %loop to %b
fir.result %b
} else {
%new_storage = fir.allocmem %rhs_shape
%lhs = fir.array_load %new_storage
%loop = fir.do_loop {
....
}
fir.array_merge_store %lhs, %loop to %new_storage
fir.result %new_storage
}
// deallocate old storage if reallocation occured,
// and update b descriptor if needed.
Note that there are actually 3 branches in FIR, so the assignment loops
are currently produced in three copies, which is a code-size issue.
It is possible to generate just two branches with two copies of the loops,
but it is not addressed in this change-set.
Differential Revision: https://reviews.llvm.org/D129314
* Fix assertion strings.
* Fixes assertion that arose from bad FIR being constructed.
With the default member-wise component assignment, the LHS and RHS may
be compatible but distinct types. This change to lowering manages both
the LHS and RHS independently rather than assume the two types are
identical. This avoids creating bogus FIR and asserting/crashing in
codegen.
Update the tests with the member-wise copy code.
This patch is part of the upstreaming effort from fir-dev branch.
Co-authored-by: Eric Schweitz <eschweitz@nvidia.com>
Reviewed By: jeanPerier
Differential Revision: https://reviews.llvm.org/D127297
Flang is manually mangling names for memset/memcpy/memmove
intrinsics, so we need to update the mangling to use the opaque
pointer format (p0 instead of p0i8).
In FIR, we want to wrap function pointers in a special box known as a
boxproc value. Fortran has a limited form of dynamic scoping
[https://tinyurl.com/2p8v2hw7] between "host procedures" and "internal
procedures". There are a number of implementations possible.
Boxproc typed values abstract away the implementation details of when a
function pointer can be passed directly (as a raw address) and when a
function pointer has to account for the presence of a dynamic scope.
When lowering Fortran syntax to FIR, all function pointers are emboxed
as boxproc values.
When creating LLVM IR, we must strip away the abstraction and produce
low-level LLVM "assembly" code. This patch implements that
transformation as converting the boxproc values to either raw function
pointers or executable trampolines on the stack as needed. The
trampoline then captures the dynamic scope context within an executable
thunk that can be passed instead of the function's raw address.
Some extra handling is required for Fortran functions that return a
character value to deal with LEN values here.
Some of the code in Bridge.cpp and ConvertExpr.cpp and be re-arranged to
faciliate the upstreaming effort.
This patch is part of the upstreaming effort from fir-dev branch.
Reviewed By: jeanPerier, PeteSteinfeld
Differential Revision: https://reviews.llvm.org/D122223
Co-authored-by: mleair <leairmark@gmail.com>
Co-authored-by: Jean Perier <jperier@nvidia.com>
Co-authored-by: Eric Schweitz <eschweitz@nvidia.com>
Co-authored-by: V Donaldson <vdonaldson@nvidia.com>
Co-authored-by: Kiran Chandramohan <kiran.chandramohan@arm.com>
This patch enables the lowering of various allocatable assignements
for character type and numeric types.
This patch is part of the upstreaming effort from fir-dev branch.
Depends on D120819
Reviewed By: PeteSteinfeld, schweitz
Differential Revision: https://reviews.llvm.org/D120820
Co-authored-by: Eric Schweitz <eschweitz@nvidia.com>
Co-authored-by: Jean Perier <jperier@nvidia.com>
This patch enables the lowering of basic modules and functions/subroutines
in modules.
This patch is part of the upstreaming effort from fir-dev branch.
Reviewed By: PeteSteinfeld
Differential Revision: https://reviews.llvm.org/D120819
Co-authored-by: Eric Schweitz <eschweitz@nvidia.com>
Co-authored-by: Jean Perier <jperier@nvidia.com>
Add lowering for simple assignement on allocatable
scalars.
This patch is part of the upstreaming effort from fir-dev branch.
Depends on D120483
Reviewed By: PeteSteinfeld
Differential Revision: https://reviews.llvm.org/D120488
Co-authored-by: Eric Schweitz <eschweitz@nvidia.com>
Co-authored-by: Jean Perier <jperier@nvidia.com>
