[flang] Fold calls to ISHFTC()

The integer arithmetic template supports ISHFTC() but the
integer intrinsic folding code had yet to call it; finish
the job.

Differential Revision: https://reviews.ll

[flang] Fold calls to ISHFTC()

The integer arithmetic template supports ISHFTC() but the
integer intrinsic folding code had yet to call it; finish
the job.

Differential Revision: https://reviews.llvm.org/D130379

show more ...

[flang] Fold TRANSFER()

Fold usage of the raw data reinterpretation intrinsic function TRANSFER().

Differential Revision: https://reviews.llvm.org/D129671

[flang] Establish a single source of target information for semantics

Create a TargetCharacteristics class to centralize the few items of
target specific information that are relevant to semantics.

[flang] Establish a single source of target information for semantics

Create a TargetCharacteristics class to centralize the few items of
target specific information that are relevant to semantics. Use the
new class for all target queries, including derived type component layout
modeling.

Future work will initialize this class with target information
provided or forwarded by the drivers, and use it to fold layout-dependent
intrinsic functions like TRANSFER().

Differential Revision: https://reviews.llvm.org/D129018

Updates: Attempts to work around build issues on Windows.

show more ...

[flang] When folding FINDLOC, convert operands to a common type

For example, FINDLOC(A,X) should convert both A and X to COMPLEX(8)
if the operands are REAL(8) and COMPLEX(4), so that comparisons
ca

[flang] When folding FINDLOC, convert operands to a common type

For example, FINDLOC(A,X) should convert both A and X to COMPLEX(8)
if the operands are REAL(8) and COMPLEX(4), so that comparisons
can be done without losing inforation. The current implementation
unconditionally converts X to the type of the array A.

Differential Revision: https://reviews.llvm.org/D127030

show more ...

[flang] Support FINDLOC/MAXLOC/MINLOC with scalar mask

Previously MASK= elements were accessed in assumption that mask is an array of
input argument rank (and in combination with explicit DIM= argum

[flang] Support FINDLOC/MAXLOC/MINLOC with scalar mask

Previously MASK= elements were accessed in assumption that mask is an array of
input argument rank (and in combination with explicit DIM= argument we had
out-of-bounds access), but for MAXLOC/MINLOC/FINDLOC mask should be be
conformable and could be scalar.

Add new regression tests with scalar mask for verification.

Reviewed By: klausler

Differential Revision: https://reviews.llvm.org/D124408

show more ...

[flang] Fix UBOUND() constant folding for parentheses expr

Similarly to LBOUND((x)) in https://reviews.llvm.org/D123838 - fix UBOUND((x))
folding for constant arrays to return shape instead of recur

[flang] Fix UBOUND() constant folding for parentheses expr

Similarly to LBOUND((x)) in https://reviews.llvm.org/D123838 - fix UBOUND((x))
folding for constant arrays to return shape instead of recurse scan.

Depends on D123520

Reviewed By: jeanPerier

Differential Revision: https://reviews.llvm.org/D123944

show more ...

[flang] Fix UBOUND() folding for constant arrays

Similarly to LBOUND in https://reviews.llvm.org/D123237, fix UBOUND() folding
for constant arrays (for both w/ and w/o DIM=): convert
GetConstantArra

[flang] Fix UBOUND() folding for constant arrays

Similarly to LBOUND in https://reviews.llvm.org/D123237, fix UBOUND() folding
for constant arrays (for both w/ and w/o DIM=): convert
GetConstantArrayLboundHelper into common helper class for both lower/upper
bounds.

Reviewed By: jeanPerier

Differential Revision: https://reviews.llvm.org/D123520

show more ...

[flang] Set LBOUND() folding for (x) expression as ones

Set LBOUND() constant folding for parentheses expr. as ones

Array bounds should not propagate throught omitted bounds specifications or
tempo

[flang] Set LBOUND() folding for (x) expression as ones

Set LBOUND() constant folding for parentheses expr. as ones

Array bounds should not propagate throught omitted bounds specifications or
temporary variables - fix constant folding in case of Parentheses<T> expression
by explicitly returning array of ones (or scalar in case of DIM=).

Add set of tests for (x) bounds checks (w/ and w/o 'parameter' arrays)

Reviewed By: jeanPerier

Differential Revision: https://reviews.llvm.org/D123838

show more ...

[flang] Fix LBOUND() folding for constant arrays

Previously constant folding uses 'dim' without checks which leads to ICE if we
do not have DIM= parameter. And for inputs without DIM= we need to for

[flang] Fix LBOUND() folding for constant arrays

Previously constant folding uses 'dim' without checks which leads to ICE if we
do not have DIM= parameter. And for inputs without DIM= we need to form an
array of rank size with computed bounds instead of single value.

Add additional PackageConstant function to simplify 'if (dim)' handling since we
need to distinguish between scalar initialization in case of DIM= argument and
rank=1 array.

Also add a few more tests with 'parameter' type to verify folding for constant
arrays.

Reviewed By: jeanPerier

Differential Revision: https://reviews.llvm.org/D123237

show more ...

[flang] Add & use a better visit() (take 2)

Adds flang/include/flang/Common/log2-visit.h, which defines
a Fortran::common::visit() template function that is a drop-in
replacement for std::visit().

[flang] Add & use a better visit() (take 2)

Adds flang/include/flang/Common/log2-visit.h, which defines
a Fortran::common::visit() template function that is a drop-in
replacement for std::visit(). Modifies most use sites in
the front-end and runtime to use common::visit().

The C++ standard mandates that std::visit() have O(1) execution
time, which forces implementations to build dispatch tables.
This new common::visit() is O(log2 N) in the number of alternatives
in a variant<>, but that N tends to be small and so this change
produces a fairly significant improvement in compiler build
memory requirements, a 5-10% improvement in compiler build time,
and a small improvement in compiler execution time.

Building with -DFLANG_USE_STD_VISIT causes common::visit()
to be an alias for std::visit().

Calls to common::visit() with multiple variant arguments
are referred to std::visit(), pending further work.

This change is enabled only for GCC builds with GCC >= 9;
an earlier attempt (D122441) ran into bugs in some versions of
clang and was reverted rather than simply disabled; and it is
not well tested with MSVC. In non-GCC and older GCC builds,
common::visit() is simply an alias for std::visit().

show more ...

[flang] Fold IBITS() intrinsic function

Implement constant folding of IBITS(); add test.

Differential Revision: https://reviews.llvm.org/D123707

[flang] prevent undefined behavior in character MAXLOC folding

When folding MAXLOC/MINLOC, the current element being compared was moved twice
in row in case it became the new extremum. With numeric

[flang] prevent undefined behavior in character MAXLOC folding

When folding MAXLOC/MINLOC, the current element being compared was moved twice
in row in case it became the new extremum. With numeric and logical types, it
made no difference (std::move is a no-op for them), but for characters
where the string storage is actually moved, it caused the new extremum to
be set to the empty string, leading to wrong results.

Note: I could have left the first std::move relating to logical Findloc, but it
brings nothing and makes the code less auditable, so I also removed it.

Differential Revision: https://reviews.llvm.org/D122590

show more ...

Revert "[flang] Add & use a better visit()"

This reverts commit 2ab9990c9eb79682a4d4b183dfbc7612d3e55328. It has
caused multiple build failures:
* https://lab.llvm.org/buildbot/#/builders/177/build

Revert "[flang] Add & use a better visit()"

This reverts commit 2ab9990c9eb79682a4d4b183dfbc7612d3e55328. It has
caused multiple build failures:
* https://lab.llvm.org/buildbot/#/builders/177/builds/4346
* https://lab.llvm.org/buildbot/#/builders/180/builds/3803
* https://lab.llvm.org/buildbot/#/builders/175/builds/10419
* https://lab.llvm.org/buildbot/#/builders/191/builds/4318
* https://lab.llvm.org/buildbot/#/builders/173/builds/4274
* https://lab.llvm.org/buildbot/#/builders/181/builds/4297

All these bots failed with a time-out:
```
command timed out: 1200 seconds without output running [b'ninja', b'-j', b'32'], attempting to kill
```
I'm guessing that that's due to template instantiations failing at some
point (https://reviews.llvm.org/D122441 introduced a custom
implementation of std::visit). Everything seems fine when either:
* building on X86 with GCC or Clang (tested with GCC 9.3 and Clang 12)
* building on AArch64 with GCC (tested with GCC 11)

show more ...

[flang] Add & use a better visit()

Adds flang/include/flang/Common/visit.h, which defines
a Fortran::common::visit() template function that is a drop-in
replacement for std::visit(). Modifies most

[flang] Add & use a better visit()

Adds flang/include/flang/Common/visit.h, which defines
a Fortran::common::visit() template function that is a drop-in
replacement for std::visit(). Modifies most use sites in
the front-end and runtime to use common::visit().

The C++ standard mandates that std::visit() have O(1) execution
time, which forces implementations to build dispatch tables.
This new common::visit() is O(log2 N) in the number of alternatives
in a variant<>, but that N tends to be small and so this change
produces a fairly significant improvement in compiler build
memory requirements, a 5-10% improvement in compiler build time,
and a small improvement in compiler execution time.

Building with -DFLANG_USE_STD_VISIT causes common::visit()
to be an alias for std::visit().

Calls to common::visit() with multiple variant arguments
are referred to std::visit(), pending further work.

Differential Revision: https://reviews.llvm.org/D122441

show more ...

[flang] UBOUND() edge case: empty dimension

Similarly to LBOUND in https://reviews.llvm.org/D121488, UBOUND must
return zero for an empty dimension, no matter the specification
expression.

Add a Ge

[flang] UBOUND() edge case: empty dimension

Similarly to LBOUND in https://reviews.llvm.org/D121488, UBOUND must
return zero for an empty dimension, no matter the specification
expression.

Add a GetUBOUND method to be used in expression rewrite that prevents
folding UBOUND to a bound specification expression if the extent is
not a compile time constant.

Fold the case where the extents is known to be zero (and also deal with
this case in LBOUND since we can and should to comply with constant
expression requirements).

Differential Revision: https://reviews.llvm.org/D122242

show more ...

[flang] LBOUND() edge case: empty dimension

LBOUND must return 1 for an empty dimension, no matter what
explicit expression might appear in a declaration or arrive in
a descriptor.

Differential Rev

[flang] LBOUND() edge case: empty dimension

LBOUND must return 1 for an empty dimension, no matter what
explicit expression might appear in a declaration or arrive in
a descriptor.

Differential Revision: https://reviews.llvm.org/D121488

show more ...

[flang] Distinguish usage and portability warning messages

Using recently established message severity codes, upgrade
non-fatal messages to usage and portability warnings as
appropriate.

Differenti

[flang] Distinguish usage and portability warning messages

Using recently established message severity codes, upgrade
non-fatal messages to usage and portability warnings as
appropriate.

Differential Revision: https://reviews.llvm.org/D121246

show more ...

[flang] Accommodate arrays with a zero-extent dimension in location folding

The index incrementation code used for FINDLOC, MAXLOC, and MINLOC folding
would crash if the array had a zero extent on t

[flang] Accommodate arrays with a zero-extent dimension in location folding

The index incrementation code used for FINDLOC, MAXLOC, and MINLOC folding
would crash if the array had a zero extent on the dimension selected with
a DIM= argument since the subscript passed to IncrementSubscripts would
have a value less than the lower bound. Fix, and add tests.

Differential Revision: https://reviews.llvm.org/D121125

show more ...

Folding in the front end was replacing calls to LEN and dropping
arguments even in situations where the arguments are required to compute
the LEN value at runtime.

Add tests.

Differential Revision:

Folding in the front end was replacing calls to LEN and dropping
arguments even in situations where the arguments are required to compute
the LEN value at runtime.

Add tests.

Differential Revision: https://reviews.llvm.org/D119373

show more ...

[flang] Fold SCALE()

Fold references to the intrinsic function SCALE().

(Also work around some MSVC headaches somehow exposed by
this patch: disable a bogus MSVC warning that began to appear
in unr

[flang] Fold SCALE()

Fold references to the intrinsic function SCALE().

(Also work around some MSVC headaches somehow exposed by
this patch: disable a bogus MSVC warning that began to appear
in unrelated source files, and avoid the otherwise-necessary
use of the "template" keyword in a call to a template member
function of a class template.)

Differential Revision: https://reviews.llvm.org/D117150

show more ...

[flang] Support extension intrinsic function variations on ABS

Accept the legacy specific intrinsic names BABS, IIABS, JIABS,
KIABS, and ZABS as well.

Differential Revision: https://reviews.llvm.or

[flang] Support extension intrinsic function variations on ABS

Accept the legacy specific intrinsic names BABS, IIABS, JIABS,
KIABS, and ZABS as well.

Differential Revision: https://reviews.llvm.org/D117155

show more ...

[flang] Do not lose call in shape inquiry on function reference

Currently, something like `print *, size(foo(n,m))` was rewritten
to `print *, size(foo_result_symbol)` when foo result is a non const

[flang] Do not lose call in shape inquiry on function reference

Currently, something like `print *, size(foo(n,m))` was rewritten
to `print *, size(foo_result_symbol)` when foo result is a non constant
shape array. This cannot be processed by lowering or reprocessed by a
Fortran compiler since the syntax is wrong (`foo_result_symbol` is
unknown on the caller side) and the arguments are lost when they might
be required to compute the result shape.

It is not possible (and probably not desired) to make GetShape fail in
general in such case since returning nullopt seems only expected for
scalars or assumed rank (see GetRank usage in lib/Semantics/check-call.cpp),
and returning a vector with nullopt extent may trigger some checks to
believe they are facing an assumed size (like here in intrinsic argument
checks: https://github.com/llvm/llvm-project/blob/196204c72c68a577c72af95d70f18e3550939a5e/flang/lib/Evaluate/intrinsics.cpp#L1530).

Hence, I went for a solution that limits the rewrite change to folding
(where the original expression is returned if the shape depends on a non
constant shape from a call).

I added a non default option to GetShapeHelper that prevents the rewrite
of shape inquiry on calls to descriptor inquiries. At first I wanted to
avoid touching GetShapeHelper, but it would require to re-implement all
its logic to determine if the shape comes from a function call or not
(the expression could be `size(1+foo(n,m))`). So added an alternate
entry point to GetShapeHelper seemed the cleanest solution to me.

Differential Revision: https://reviews.llvm.org/D116933

show more ...

[flang] Fix combined folding of FINDLOC/MAXLOC/MINLOC

The tests for folding these intrinsics neglected to name the
logical scalars with a leading "test_", so test failures caused
by recent work to i

[flang] Fix combined folding of FINDLOC/MAXLOC/MINLOC

The tests for folding these intrinsics neglected to name the
logical scalars with a leading "test_", so test failures caused
by recent work to implement a combined constant folding facility
for these intrinsics wasn't catching some bugs. This patch fixes
the tests and the bugs.

Differential Revision: https://reviews.llvm.org/D112741

show more ...

[flang] Fix bogus folding error for ISHFT(x, negative)

Negative shift counts are of course valid for ISHFT when
shifting to the right. This patch decouples the folding of
ISHFT from that of SHIFTA/

[flang] Fix bogus folding error for ISHFT(x, negative)

Negative shift counts are of course valid for ISHFT when
shifting to the right. This patch decouples the folding of
ISHFT from that of SHIFTA/L/R and adds tests.

Differential Revision: https://reviews.llvm.org/D112244

show more ...

[flang] Fix capitalization of "ishft"

We weren't recognizing the ISHFT intrinsic because the code had
incorrectly capitalized it.

Differential Revision: https://reviews.llvm.org/D111449