Commit Graph

345 Commits

Author SHA1 Message Date
Peter Klausler 46c49e66d8 [flang] Extend characterization & checking for procedure bindings
Procedure bindings with explicit interfaces don't work when the
interface is shadowed by a generic interface of the same name,
and can produce spurious semantic error messages.  Extend the
characterization and checking code for such things, and the utility
functionns on which they depend, to dig through generics when they
occlude interface-defining subprograms.  This is done on demand in
checking code, not once during name resolution, because the
procedures in question may also be forward-referenced.

Differential Revision: https://reviews.llvm.org/D131105

diff --git a/flang/include/flang/Semantics/symbol.h b/flang/include/flang/Semantics/symbol.h
index e79f8ab6503e..0b03bf06eb73 100644
--- a/flang/include/flang/Semantics/symbol.h
2022-08-09 12:01:45 -07:00
V Donaldson cc71e69459 [flang] Intrinsic RANDOM_SEED calls with dynamically absent/present arguments 2022-08-09 09:08:55 -07:00
Peter Klausler 5e8094bae5 [flang] Don't inherit ELEMENTAL attribute from intrinsics for TBP bindings
Type-bound procedure bindings that specify intrinsic procedures as their
interfaces should not acquire the ELEMENTAL attribute from the purposes
of compatibility checking between inherited bindings and their overrides
in extended derived types.

Differential Revision: https://reviews.llvm.org/D131104
2022-08-09 08:09:32 -07:00
Peter Klausler 9d084982a3 [flang] Clarify CheckReductionDIM()
This utility routine in constant folding should return false when
a DIM= actual argument to a reduction intrinsic function has a
value that prevents folding, and true when folding can proceed.
The implementation was returning true in cases where a DIM=
argument was present but not constant.

Clarify the code and add commentary: a true result means that
there is no DIM= actual argument present, or that a DIM= argument
exists, is constant, and has a value that is in range.

Differential Revision: https://reviews.llvm.org/D131101
2022-08-09 05:51:45 -07:00
Peter Klausler 1d1f5a5251 [flang] Handle subnormals while folding SCALE, SET_EXPONENT, & FRACTION
The implementations of folding for the intrinsic functions SCALE and SET_EXPONENT
do not cope correctly with numbers in the subnormal range.  Fix SCALE,
then modify SET_EXPONENT to be a special case of SCALE.

Differential Revision: https://reviews.llvm.org/D131099
2022-08-07 16:12:14 -07:00
Peter Klausler 3f10091c04 [flang] Allow pure function references in expandable scalar
F18 disallows function references and coarray references from
appearing in scalar expressions that are to be expanded into
arrays to conform with other operands or actual arguments in
an elemental expression.  This is too strong, as pure procedures
can be safely used.

Differential Revision: https://reviews.llvm.org/D131096
2022-08-07 09:12:46 -07:00
Katherine Rasmussen 6ac30fa6e9 [flang] Add stopped_images to list of intrinsics and add test
Add stopped_images to the list of intrinsic functions. Add a
semantics test for stopped_images.

Reviewed By: klausler, ngeorge1098

Differential Revision: https://reviews.llvm.org/D129513
2022-08-02 17:01:32 -07:00
Peter Klausler 95f4ca7f5d [flang] Allow restricted specific intrinsic functions as implicitly-interfaced procedure pointer targets
The predicate "CanBeCalledViaImplicitInterface()" was returning false for
restricted specific intrinsic functions (e.g., SIN) because their procedure
characteristics have the elemental attribute; this leads to a bogus semantic
error when one attempts to use them as proc-targets in procedure pointer
assignment statements when the left-hand side of the assignment is a procedure
pointer with an implicit interface.  However, these restricted specific intrinsic
functions have always been allowed as special cases for such usage -- it is
as if they are elemental when it is necessary for them to be so, but not
when it's a problem.

Differential Revision: https://reviews.llvm.org/D130386
2022-07-25 12:19:49 -07:00
Peter Klausler 90c4eda3d2 [flang] Dial some errors down to warnings for ASSOCIATED()
When a procedure pointer is associated with a procedure target, f18
will emit hard error messages if the pointer is incompatible with the
target in a way that would cause the program to not work if the
procedure pointer were actually called.  However, in the context of
the ASSOCIATED() intrinsic, the compiler should not consider a query
to be a compilation-time error if the pointer and the target are
incompatible.  The standard gives us sufficient wiggle room here
to treat these cases as warnings.

Attempts to use ASSOCIATED to test whether a procedure pointer is
associated with a data object, or vice versa, remain errors.

Differential Revision: https://reviews.llvm.org/D130384
2022-07-25 11:06:30 -07:00
Peter Klausler b09c890510 [flang] Clean up bogus semantic error on procedure pointer assignment
When a procedure pointer with no interface is associated with
an EXTERNAL name with no interface information, but it is later
inferred that the procedure pointer must be a subroutine because it
appears in a CALL statement, don't complain that the EXTERNAL name
is not also known to be a subroutine.

Subroutine vs. function errors are still caught in procedure pointer
assignment compatibility checking; this fix simply ensures that those
more nuanced tests are not overridded by the attribute set equality test.

Also, leave in some code for dumping the differing attributes in legitimate
error cases that was added in the coures of debugging the specific problem.

Differential Revision: https://reviews.llvm.org/D130385
2022-07-23 10:18:28 -07:00
Peter Klausler 3096b85696 [flang] Don't fold zero-length substring references
In some contexts the code looks cleaner if we fold zero-length substring
references into empty character constants, but those don't work in
variable definition contexts and can lead to bogus semantic error
messages.

Differential Revision: https://reviews.llvm.org/D130383
2022-07-23 10:08:09 -07:00
Peter Klausler cbfc223920 [flang] Fix name of dummy argument to intrinsic NEW_LINE(A='')
It should be A= but I misspelled it in the intrinsics table as X=.

Differential Revision: https://reviews.llvm.org/D130382
2022-07-23 09:30:56 -07:00
Peter Klausler baec06a9d4 [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
2022-07-22 18:21:57 -07:00
Peter Klausler 60b1fcb1a5 [flang] Correct folding of TRANSFER(integer, character array)
The code that copies data from a constant source array into a character
array constant result was failing to copy its last element if it was
only partially defined due to misalignment.

Differential Revision: https://reviews.llvm.org/D130376
2022-07-22 17:28:08 -07:00
Peter Klausler 0b8377534e [flang] Fold SET_EXPONENT() and FRACTION()
Fold the intrinsic function SET_EXPONENT() and its special case,
FRACTION().

Differential Revision: https://reviews.llvm.org/D130378
2022-07-22 15:44:54 -07:00
Tarun Prabhu 7709f12ed0 Bitwise comparison intrinsics
This patch implements lowering for the F08 bitwise comparison intrinsics
(BGE, BGT, BLE and BLT).

This does not create any runtime functions since the functionality is
simple enough to carry out in IR.

The existing semantic check has been changed because it unconditionally
converted the arguments to the largest possible integer type. This
resulted in the argument with the smaller bit-size being sign-extended.
However, the standard requires the argument with the smaller bit-size to
be zero-extended.

Reviewed By: klausler, jeanPerier

Differential Revision: https://reviews.llvm.org/D127805
2022-07-19 16:41:04 +00:00
Katherine Rasmussen ebf3dbbe15 Revert "[flang] Add co_sum to the list of intrinsics and update test"
This reverts commit d2460d9008.

Reverting this commit because after pushing to main it caused
unexpected test failures.
2022-07-14 14:44:34 -07:00
Katherine Rasmussen d2460d9008 [flang] Add co_sum to the list of intrinsics and update test
Add the collective subroutine, co_sum, to the list of intrinsics.
In accordance with 16.9.50 and 16.9.137, add a check for and an
error if coindexed objects are being passed to certain arguments
in co_sum and in move_alloc. Add a semantics test to check that
this error is successfully caught in calls to move_alloc. Remove
the XFAIL directive, update the ERROR directives and add both
standard-conforming and non-standard conforming calls to the
semantics test for co_sum.

Reviewed By: jeanPerier

Differential Revision: https://reviews.llvm.org/D114134
2022-07-14 13:49:38 -07:00
Peter Klausler be68a6adfb [flang] Error detection/avoidance for TRANSFER with empty MOLD= type
When MOLD= is an array and there is no SIZE= in a call to TRANSFER(),
the size of an element of the MOLD= is used as the denominator in a
division to establish the extent of the vector result.  When the
total storage size of the SOURCE= is known to be zero, the result is
empty and no division is needed.

To avoid a division by zero at runtime, we need to check for a zero-sized
MOLD= element type when the storage size of SOURCE= is nonzero and there
is no SIZE=.  Further, in the compilation-time rewriting of calls to
SHAPE(TRANSFER(...)) and SIZE(TRANSFER(...)) for constant folding and
simplification purposes, we can't replace the call with an arithmetic
element count expression when the storage size of SOURCE= is not known
to be zero and the element size of MOLD= is not known to be nonzero at
compilation time.

These changes mostly affect tests using a MOLD= argument that is an
assumed-length character.

Differential Revision: https://reviews.llvm.org/D129680
2022-07-13 16:50:57 -07:00
Peter Klausler ae93d8ea42 [flang] Fold TRANSFER()
Fold usage of the raw data reinterpretation intrinsic function TRANSFER().

Differential Revision: https://reviews.llvm.org/D129671
2022-07-13 15:34:48 -07:00
Peter Klausler 62d874f203 [flang] Refine semantic checks for procedure pointer assignment
Some procedure pointers and EXTERNAL procedures have neither
explicit interfaces nor result types; these procedures are obviously
not known to be functions, but they could be, so semantics must not
assume that they are necessarily subroutines.  Refine the procedure
pointer / dummy procedure compatibility check to handle these more
ambiguous cases and not elicit inappropriate error messages.

Differential Revision: https://reviews.llvm.org/D129674
2022-07-13 14:56:50 -07:00
Katherine Rasmussen 9bb18a983f [flang] Add semantics test for image_status and add a check
Add a semantics test for the intrinsic function image_status. Add
a check and restriction on the image argument in image_status,
ensuring that it is a positive value. Add same check on the
size argument of the intrinsic ishftc. Add another check on
the shift argument of ishftc, ensuring that it is less than or
equal to the size argument. Add a short semantics test checking
these restrictions in ishftc function calls.

Reviewed By: klausler

Differential Revision: https://reviews.llvm.org/D128009
2022-07-11 10:54:12 -07:00
Peter Klausler 6052025b58 [flang] Add IsElementalProcedure() predicate
Replace most tests of the explicit Attr::ELEMENTAL symbol flag with
a new predicate IsElementalProcedure() that works correctly for alternate
ENTRY points and does the right thing for procedure interfaces that
reference elemental intrinsic functions like SIN() whose elemental
nature does not propagate.

Differential Revision: https://reviews.llvm.org/D129022
2022-07-06 18:08:45 -07:00
Peter Klausler 715283aa17 [flang] Cope with overflow in real MOD/MODULO
In folding and in the runtime library for real MOD/MODULO(A,P),
detect overflow from the division A/P and return a properly signed
zero result.  (When A/P overflows and both A and P are finite numbers
with nonzero P, the quotient would be a large integer when rounded to
the precision of the floating-point representation.)

Differential Revision: https://reviews.llvm.org/D129020
2022-07-06 17:31:11 -07:00
Peter Klausler 23c2bedfd9 [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.
2022-07-06 10:25:34 -07:00
Peter Klausler b70f507c75 [flang] Fix folding of LEN(f(...))
LEN(f(...)), where "f" is a non-intrinsic function, should not be folded
to anything else unless the result is a known constant value.  While there
are conceivable cases in which we could do better (e.g., an internal function
whose length is a host-associated INTENT(IN) dummy argument), there are
other cases that we're getting wrong.

Differential Revision: https://reviews.llvm.org/D128759
2022-06-29 10:25:07 -07:00
Peter Klausler 1ef5e6de76 [flang] Make SQRT folding exact
Replace the latter half of the SQRT() folding algorithm with code that
calculates an exact root with extra rounding bits, and then lets the
usual normalization and rounding code do the right thing.  Extend
tests to catch regressions.

Differential Revision: https://reviews.llvm.org/D128395
2022-06-23 11:16:39 -07:00
Peter Klausler dfaa3880e1 [flang] Fix wording of warning message
"division on intrinsic call" should read "division by zero on intrinsic call".

Differential Revision: https://reviews.llvm.org/D128394
2022-06-23 11:15:35 -07:00
Peter Klausler b6fce8b92d [flang] Fix bogus errors from SIZE/SHAPE/UBOUND on assumed-shape
While it is indeed an error to use SIZE, SHAPE, or UBOUND on an
assumed-shape dummy argument without also supplying a DIM= argument
to the intrinsic function, it is *not* an error to use these intrinsic
functions on sections or expressions of such arrays.  Refine the test
used for the error message.

Differential Revision: https://reviews.llvm.org/D128391
2022-06-23 10:32:22 -07:00
Daniil Dudkin 4f1fa558c8 [flang][NFC] Small refactor for `IsProcedurePointer`
Instead of manually checking for procedure-like details in Symbol,
defer it to IsProcedure function.

Differential Revision: https://reviews.llvm.org/D127967
2022-06-20 11:10:30 +03:00
Peter Klausler 2815bacc91 [flang] Fix error message
A message has a %s string substitution in it but somebody (probably me)
forgot to pass the argument that defines it.

Differential Revision: https://reviews.llvm.org/D127794
2022-06-15 15:30:14 -07:00
Katherine Rasmussen 2eeafa2022 [flang] Add failed_images to list of intrinsics and add test
Add failed_images to the list of intrinsic functions. Add a
semantics test for failed_images.

Reviewed By: jeanPerier

Differential Revision: https://reviews.llvm.org/D126805
2022-06-14 14:13:33 -07:00
Katherine Rasmussen 473d780692 [flang] Add team_type to num_images intrinsic call
num_images had previously been added to the list of intrinsics
before the type team_type had been implemented. Now that team_type
is implemented, add the num_images call that has the team argument.
Update the semantics tests for num_images.

Reviewed By: craig.rasmussen

Differential Revision: https://reviews.llvm.org/D126734
2022-06-14 11:28:46 -07:00
Peter Klausler 4daa33f6d1 [flang][runtime] Use __float128 where possible & needed in runtime
On targets with __float128 available and distinct from long double,
use it to support more kind=16 entry points.  This affects mostly
x86-64 targets.  This means that more runtime entry points are
defined for lowering to call.

Delete Common/long-double.h and its LONG_DOUBLE macro in favor of
testing the standard macro LDBL_MANT_DIG.

Differential Revision: https://reviews.llvm.org/D127025
2022-06-05 09:16:57 -07:00
Peter Klausler ed71a0b45b [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
2022-06-04 09:26:13 -07:00
Peter Klausler d484fe93d4 [flang] Don't crash on initialization with a zero-sized derived type
Avoid calls to memcpy with zero byte counts if their address argument
calculations may not be valid expressions.

Differential Revision: https://reviews.llvm.org/D127027
2022-06-04 08:58:16 -07:00
Peter Klausler 08c6a32381 [flang] Don't discard lower bounds of implicit-shape named constants
F18 preserves lower bounds of explicit-shape named constant arrays, but
failed to also do so for implicit-shape named constants.  Fix.

Differential Revision: https://reviews.llvm.org/D127021
2022-06-03 22:45:12 -07:00
Peter Klausler e0adee8481 [flang] Correct folding of CSHIFT and EOSHIFT for DIM>1
The algorithm was wrong for higher dimensions, and so were
the expected test results.  Rework.

Differential Revision: https://reviews.llvm.org/D127018
2022-06-03 18:59:44 -07:00
Peter Klausler 66a871b973 [flang] Fix crash in IsSaved()
Code was accessing ProcEntityDetails in a symbol that didn't have them.

Differential Revision: https://reviews.llvm.org/D127011
2022-06-03 17:00:01 -07:00
Peter Klausler 73506256bf [flang] Avoid spurious warnings from reading module files
When processing the literal constants of the various kinds of
INTEGER that are too large by 1 (e.g., 2147483648_4) in expression
analysis, emit a portability warning rather than a fatal error if
the literal constant appears as the operand to a unary minus, since
the folded result will be in range.  And don't emit any warning if
the negated literal is coming from a module file -- f18 wrote the
module file and the warning would simply be confusing, especially to
the programmer that wrote (-2147483647_4-1) in the first place.

Further, emit portability warnings for the canonical expressions for
infinities and NaN (-1./0., 0./0., & 1./0.), but not when they appear
in a module file, for the same reason.  The Fortran language has no
syntax for these special values so we have to emit expressions that
fold to them.

Fixes LLVM bugs https://github.com/llvm/llvm-project/issues/55086 and
https://github.com/llvm/llvm-project/issues/55081.

Differential Revision: https://reviews.llvm.org/D126584
2022-05-28 08:07:54 -07:00
Peter Klausler 574f9dfee8 [flang] Extension: Accept Hollerith actual arguments as if they were BOZ
When a Hollerith (or short character) literal is presented as an actual
argument that corresponds to a dummy argument for which a BOZ literal
would be acceptable, treat the Hollerith as if it had been a BOZ
literal in the same way -- and with the same code -- as f18 already
does for the similar extension in DATA statements.

Differential Revision: https://reviews.llvm.org/D126144
2022-05-24 09:04:31 -07:00
Peter Klausler 7f680b260f [flang] Allow more forward references to ENTRY names
Forward references to ENTRY names to pass them as actual procedure arguments
don't work in all cases, exposing some basic ordering problems in
name resolution for these symbols.  Refactor; create all the
necessary procedure symbols, and either function result or host association
symbols (for subroutines), at the time that the subprogrma scope is
created, so that the names exist in the scope as text "before"
the ENTRY is processed in name resolution.  Some processing
remains in PostEntryStmt() so that we can check that an ENTRY with
an explicit distinct RESULT doesn't also have declarations for the
ENTRY name.

Differential Revision: https://reviews.llvm.org/D126142
2022-05-23 21:48:35 -07:00
Daniil Dudkin a61835b1e3 [flang] Fix use-associated false-positive error
For the program provided as the test case flang fired the following
error:

    error: Semantic errors in main.f90
    error: 'foo' is not a procedure

This change fixes the error by postponing handling of `UseErrorDetails`
from `CharacterizeProcedure` to a later stage.

Reviewed By: kiranchandramohan

Differential Revision: https://reviews.llvm.org/D125791
2022-05-20 12:14:02 +03:00
Peter Klausler d80d812df0 [flang] Fix check for assumed-size arguments to SHAPE() & al.
The predicate that is used to detect an invalid assumed-size argument
to the intrinsic functions SHAPE, SIZE, & LBOUND gives false results
for arguments whose shapes are not calculatable at compilation time.
Replace with an explicit test for an assumed-size array dummy argument
symbol.

Differential Revision: https://reviews.llvm.org/D125342
2022-05-11 10:33:17 -07:00
Peter Klausler 3a26596af3 [flang] Fold complex component references
Complex component references (z%RE, z%IM) of complex named constants
should be evaluated at compilation time.

Differential Revision: https://reviews.llvm.org/D125341
2022-05-11 10:04:13 -07:00
Peter Klausler 2cd95504df [flang] Allow local variables and function result inquiries in specification expressions
Inquiries into the bounds, size, and length of local variables (and function results)
are acceptable specification expressions.  A recent change allowed them for dummy
arguments that are not OPTIONAL or INTENT(OUT), but didn't address other object
entities.

Differential Revision: https://reviews.llvm.org/D125343
2022-05-10 16:47:03 -07:00
Peter Klausler 71728360ad [flang] Fold real-valued MODULO() and MOD()
Evaluate real-valued references to the intrinsic functions MODULO
and MOD at compilation time without recourse to an external math
library.

Differential Revision: https://reviews.llvm.org/D125151
2022-05-10 08:15:29 -07:00
Peter Klausler 9e50168be4 [flang] Fold real-valued DIM()
Fold references to the intrinsic function DIM with constant real
arguments.  And clean up folding of comparisons with NaNs to address
a problem noticed in testing -- NaNs should successfully compare
unequal to all values, including themselves, instead of failing all
comparisons.

Differential Revision: https://reviews.llvm.org/D125146
2022-05-10 07:45:41 -07:00
Peter Klausler 8594b051fb [flang] Accept POINTER followed by INTERFACE
As is already supported for dummy procedures, we need to also accept
declarations of procedure pointers that consist of a POINTER attribute
statement followed by an INTERFACE block.  (The case of an INTERFACE
block followed by a POINTER statement already works.)

While cleaning this case up, adjust the utility predicate IsProcedurePointer()
to recognize it (namely a SubprogramDetails symbol with Attr::POINTER)
and delete IsProcName().  Extend tests, and add better comments to
symbol.h to document the two ways in which procedure pointers are
represented.

Differential Revision: https://reviews.llvm.org/D125139
2022-05-09 18:37:09 -07:00
Peter Klausler 5d5d2a0b19 [flang] Refine error checking in specification expressions
The rules in the Fortran standard for specification expressions
are full of special cases and exceptions, and semantics didn't get
them exactly right.  It is valid to refer to an INTENT(OUT) dummy
argument in a specification expression in the context of a
specification inquiry function like SIZE(); it is not valid to
reference an OPTIONAL dummy argument outside of the context of
PRESENT.  This patch makes the specification expression checker
a little context-sensitive about whether it's examining an actual
argument of a specification inquiry intrinsic function or not.

Differential Revision: https://reviews.llvm.org/D125131
2022-05-09 17:50:12 -07:00