The check for the PAD= setting should examine the mutable modes
of the current I/O statement, not the persistent modes of the
I/O unit.
Differential Revision: https://reviews.llvm.org/D128389
When an unconnected unit number is used in a BACKSPACE statement
with ERR=, IOSTAT=, &/or IOMSG= control specifiers, don't crash,
but let the program deal with the error.
Differential Revision: https://reviews.llvm.org/D127782
After a recoverable error condition in a READ statement with ADVANCE='NO',
skip the remainder of the current record.
Differential Revision: https://reviews.llvm.org/D127433
The little state machine in GetNextDataEdit() wasn't transitioning
properly from reading the imaginary part of the number back to the
real part for the next iteration of a repeated value.
Differential Revision: https://reviews.llvm.org/D127422
Track pending "asynchronous" I/O operation IDs so that WAIT statements can
report errors about bad ID numbers.
Lowering will need to extended to call GetAsynchronousId() for a READ or
WRITE statement with ID=n.
Differential Revision: https://reviews.llvm.org/D127421
When nonadvancing output uses T/TL control edit descriptors to reposition
the record, don't reset the position to the furthest point written at
the end of the write.
Differential Revision: https://reviews.llvm.org/D127420
When an external I/O statement is in a recoverable error
state before any data transfers take place (for example,
an unformatted transfer with ERR=/IOSTAT=/IOMSG= attempted on
a formatted unit), ensure that the unit's mutex is still
released at the end of the statement.
Differential Revision: https://reviews.llvm.org/D127032
Whether a unit number in an inquire-by-unit statement is valid or not,
it should be the value to which the NUMBER= variable is set, not -1.
-1 should be returned to NUMBER= only for an inquire-by-file statement
when the FILE= is not connected to any unit.
Differential Revision: https://reviews.llvm.org/D126145
A BACKSPACE statement on a unit after a READ or WRITE with ADVANCE="NO"
must reset the position to the beginning of the record, not to the
beginning of the previous one.
Differential Revision: https://reviews.llvm.org/D125057
When the last operation on a foramtted sequential or stream file (prior
to an implied or explicit ENDFILE) is a non-advancing WRITE, ensure
that any partial record data is emitted to the file without a line
terminator. Further, when that last record is read with a non-advancing
READ, ensure that it won't raise an end-of-record condition after its
data, but instead will signal an end-of-file.
Differential Revision: https://reviews.llvm.org/D124546
When PAD='NO' and ADVANCE='YES', we currently signal an input
error when a formatted read tries to go past the end of a record
only when a fixed RECL= is in effect. Other compilers will signal
an error without RECL= too, and that seems like a precedent we
should follow.
Differential Revision: https://reviews.llvm.org/D124301
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().
When formatted non-advancing output ends in a control edit descriptor
like nX or Tn or TRn that effectively extends the record, fill any
gap with explicit blanks at the completion of the WRITE.
Differential Revision: https://reviews.llvm.org/D123716
A recent change to implement UTF-8 encoding should have
made the encoding conditional only for CHARACTER(KIND=1)
to enable UTF-8 output vs. Latin-1 or whatever. UTF-8 output
of wider CHARACTER kinds should not be conditional (until we choose
to support UCS-16, maybe). So wider CHARACTER kinds are being
emitted with extra zero bytes; this patch fixes them.
Differential Revision: https://reviews.llvm.org/D123711
Correct the implementation of non-advancing I/O after some testing
to ensure that T tab edit descriptors are not allowed to back up
into positions of a record prior to where it stood at the beginning
of the I/O statement.
Differential Revision: https://reviews.llvm.org/D123709
STATUS='NEW' and 'REPLACE' require FILE= to be present.
STATUS='SCRATCH' may not appear with FILE=.
These errors are caught at compilation time when constant character
strings are used in an OPEN statement, but the runtime needs
to enforce them as well to catch errors in OPEN statements
with character variables and expressions.
Differential Revision: https://reviews.llvm.org/D122509
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
Implements UTF-8 encoding and decoding for external units
with OPEN(ENCODING='UTF-8'). This encoding applies to default
CHARACTER values that are not 7-bit ASCII as well as to
the wide CHARACTER kinds 2 and 4. Basic testing is in place
via direct calls to the runtime I/O APIs, but serious checkout
awaits lowering support of the wide CHARACTER kinds.
Differential Revision: https://reviews.llvm.org/D122038
Some refactoring and related fixes for more accurate
user program error recovery in the I/O runtime, especially
for error recovery with IOMSG= character values.
1) Move any work in an EndIoStatement() implementation
that may raise an error into a new CompleteOperation()
member function. This allows error handling APIs like
GetIoMsg() to complete a pending I/O statement and harvest
any errors that may result.
2) Move the pending error code from ErroneousIoStatementState
to a new pendingError_ data member in IoErrorHandler.
This allows IoErrorHandler::InError() to return a correct
result when there is a pending error that will be recovered
from so that I/O list data transfers don't crash in the meantime.
3) Don't create and leak a unit for a failed OPEN(NEWUNIT=n)
with error recovery, and don't modify 'n'. (Depends on
changes to API call ordering in lowering, in a separate patch;
code was added to ensure that OPEN statement control list
specifiers, e.g. SetFile(), must be passed before GetNewUnit().)
4) Fix the code that calls a form of strerror to fill an
IOMSG= variable so that it actually works for Fortran's
character type: blank fill with no null or newline termination.
Differential Revision: https://reviews.llvm.org/D122036
Where possible, I added additional information to the messages to help
programmers figure out what went wrong. I also removed all uses of the word
"bad" from the messages since (to me) that implies a moral judgement rather
than a programming error. I replaced it with either "invalid" or "unsupported"
where appropriate.
Differential Revision: https://reviews.llvm.org/D121493
Rather than reading default character variables in formatted
input one byte at a time via NextInField(), skip and read
them via blocks of available buffer data. This eliminates
a bottleneck that affected reads of large character values.
(It also exposed a problem with sequential reads with RECL=
set on the OPEN statement, so that's fixed too.)
Differential Revision: https://reviews.llvm.org/D121144
The runtime crashes on several fundamental I/O data transfer statement
control list errors, like list I/O on a direct-access unit, or
input from a write-only unit, &c. These errors should not be fatal
when ERR= or IOSTAT= are present.
This patch creates a new ErroneousIoStatementState class and
uses it for the state of an I/O statement that is doomed to fail
from these errors. If there is no ERR= label or IOSTAT= variable,
the error will be raised at the end of the statement. Data transfer
operations along the way will be no-op failures.
Differential Revision: https://reviews.llvm.org/D120745
Corrects the runtime implementation of I/O on files with
the access mode ACCESS='STREAM'. This is a collection
of edge-case tweaks to ensure that the distinctions between
stream and direct/sequential files, unformatted or formatted,
are respected where appropriate.
Moves NextInField() from io-stmt.h to io-stmt.cpp --
it was getting too big to keep in a header.
This patch exposed a problem with the I/O runtime
on Windows and it was reverted. This version also
fixes that problem; files are now opened on Windows
in binary mode to prevent inadvertent insertions of
carriage returns before line feeds, and those line
endings (CR+LF) are now explicitly generated.
Differential Revision: https://reviews.llvm.org/D119015
Corrects the runtime implementation of I/O on files with
the access mode ACCESS='STREAM'. This is a collection
of edge-case tweaks to ensure that the distinctions between
stream and direct/sequential files, unformatted or formatted,
are respected where appropriate.
Moves NextInField() from io-stmt.h to io-stmt.cpp --
it was getting too big to keep in a header.
Differential Revision: https://reviews.llvm.org/D118834
RECL= is required for direct access I/O, but is permitted
as well for sequential I/O, where it is defined by the
standard to specify a maximum record (line) length.
The standard does not say what should happen when an
sequential formatted input record appears whose length is
unequal to RECL= when it is specified.
Precedents from other compilers are unclear: one raises an error,
some honor RECL= as an effective truncation, and a few ignore the
situation. On output, all other compilers tested raised an
error when an attempt is made to emit a record longer than RECL=.
This patch treats RECL= as effective truncation on input and
as a hard limit with error on output, and also ensures that
RECL= can be set *longer* than the actual input record lengths.
Differential Revision: https://reviews.llvm.org/D115102
INQUIRE(POSITION=)'s results need to reflect the POSITION=
specifier used for the OPEN statement until the unit has been
repositioned. Preserve the POSITION= from OPEN and used it
for INQUIRE(POSITION=) until is becomes obsolete.
INQUIRE(PAD=) is implemented here in the case of an unconnected unit
with Fortran 2018 semantics; i.e., "UNDEFINED", rather than Fortran 90's
"YES"/"NO" (see 4.3.6 para 2). Apparent failures with F'90-only tests
will persist with INQUIRE(PAD=); these discrepancies don't seem to warrant
an option or environment variable.
To make the implementation of INQUIRE more closely match the language
in the standard, rename IsOpen() to IsConnected(), and use it explicitly
for the various INQUIRE specifiers.
Differential Revision: https://reviews.llvm.org/D114755
The predefined units were not being initialized with FORM='FORMATTED',
so INQUIRE(PAD=) was failing if no I/O had already been done.
INQUIRE(POSITION=) was returning 'REWIND' on stdin/stdout (which
is somewhat defensible from the definition, and is what Intel Fortran
does), but most implementations return 'ASIS'. Change the runtime
to return 'REWIND' only for positionable external files, but 'ASIS'
for terminals, sockets, &c.
Differential Revision: https://reviews.llvm.org/D114028
The inquire by output list form of the INQUIRE statement calculates the
number of file storage units that would be required to store the data
of an output list in an unformatted file. Currently, the result is
incorrectly multiplied by the number of bytes for a data type. A query
for "INTEGER(KIND=4) A(10)" should be 40, not 160.
Update formatting.
1. To avoid overwriting the part of the record read in the non advancing read,
the furtherPositionInRecord field must be set to the max of the
furtherPositionInRecord and the positionInRecord at the beginning of the
IO write.
2. To allow any further read to succeed after the write, the unit
beganReadingRecord_ must be set to false when resetting the recordLength
during the write, otherwise, recordLength will not be computed in further
read and an assert is hit (at unit.cpp(398)).
The added unit test exercises both of these scenarios.
Differential Revision: https://reviews.llvm.org/D113740
Profiling a basic internal real input read benchmark shows some
hot spots in the code used to prepare input for decimal-to-binary
conversion, which is of course where the time should be spent.
The library that implements decimal to/from binary conversions has
been optimized, but not the code in the Fortran runtime that calls it,
and there are some obvious light changes worth making here.
Move some member functions from *.cpp files into the class definitions
of Descriptor and IoStatementState to enable inlining and specialization.
Make GetNextInputBytes() the new basic input API within the
runtime, replacing GetCurrentChar() -- which is rewritten in terms of
GetNextInputBytes -- so that input routines can have the
ability to acquire more than one input character at a time
and amortize overhead.
These changes speed up the time to read 1M random reals
using internal I/O from a character array from 1.29s to 0.54s
on my machine, which on par with Intel Fortran and much faster than
GNU Fortran.
Differential Revision: https://reviews.llvm.org/D113697
When processing the devious NAMELIST input
&group logarray = t t t
= 666 /
for LOGICAL::logarray(3) and INTEGER::t, the runtime library
needs to do some look-ahead on the input stream to make sure
that the last "t" on the first line is a truth value rather than
an item name -- which in this case it is. This look-ahead
was implemented in a previous patch but only worked for internal
input cases; this patch implements look-ahead capabilities for
input from an external file, too (and also adjusts repeated
list-directed input items to use this infrastructure, too).
Differential Revision: https://reviews.llvm.org/D113311
ExternalFileUnit::BeginReadingRecord() must be called at least once
during an external formatted READ statement before FinishReadingRecord().
In the case of a formatted external READ with no data items, the call
to finish processing of the format (which might have lingering control
items that need doing) was taking place before the call to BeginReadingRecord
from ExternalIoStatementState::EndIoStatement. Add a call to
BeginReadingRecord on this path.
Differential Revision: https://reviews.llvm.org/D112351
Count input characters corresponding to formatted edit descriptors
for READ(SIZE=); count output bytes for INQUIRE(IOLENGTH=).
The I/O APIs GetSize() and GetLength() were adjusted to return
std::size_t as function results.
Basic unit tests were added (and others fixed).
Differential Revision: https://reviews.llvm.org/D110291
When an end of record is met in non advancing IO:
- Set IOSTAT if present according to 12.11.4 (5).
- Position the file to the next record (12.11.4 (4)).
The previous code was only signaling EOR for fixed record length IO.
Reading at 12.11.4, I do not find the rational for this condition, so I
removed it.
It also does not seem the presence of padding should prevent
the EOR signaling.
The positionning to the next record was block when EOR is signaling
in FinishReadingRecord because ErrorHandler.isError() is true in this
case.
EOR in input is not an error, but I am not confident to modify
ErrorHandler.isError() to cover that. However, In FinishReadingRecord,
the code should not bail if the error is simply an end of record.
I did not check the SIZE requirements here because GetSize runtime is
not yet implemented.
Differential Revision: https://reviews.llvm.org/D109505
Move the closure of the subset of flang/runtime/*.h header files that
are referenced by source files outside flang/runtime (apart from unit tests)
into a new directory (flang/include/flang/Runtime) so that relative
include paths into ../runtime need not be used.
flang/runtime/pgmath.h.inc is moved to flang/include/flang/Evaluate;
it's not used by the runtime.
Differential Revision: https://reviews.llvm.org/D109107
The standard specifies that the form must be set to a default at the
end of an open statement (C.7.4 point 2) where it was not specified.
Only in the case of a pre-connected unit can the form be deferred
until the first data transfer statement.
Set back the default form setting in OpenStatementState::EndIoStatement
that had been removed when deferring the pre-connected unit from setting
in 199a623ebf.
Also return "UNDEFINED" instead of "UNKNOWN" to the FORM inquiry when the
form was not yet specified as defined in 12.10.2.12.
Related test: syntax 215a216.
Differential Revision: https://reviews.llvm.org/D108990
A recent runtime I/O change[1] was meant to improve the handling of
input from external files missing a terminal newline on their last
records; the change was "triggered" by the wrong circumstances and
causing reads that should have pulled more data into the buffer to be
treated as EOFs. So fix that, and also don't retain input data
in the buffer once an input record has been finished unless it's
known that list-directed or NAMELIST input of a repeated input item
may need to backspace a non-positionable external unit to return
to the beginning of the repeated item.
[1] 6578893a0453384346f149479f8574dfff977ace
Differential Revision: https://reviews.llvm.org/D108164
A repeated null value at the end of an input record with a count > 1
would incorrectly advance to the next record when resumed. Fix.
Improve some poor naming and code flow noticed while debugging, so
next time will be easier.
Extend a unit test to check this case.
Differential Revision: https://reviews.llvm.org/D107917
Non-advancing I/O was failing; ExternalFileUnit was losing
track of what writes had been committed to the file. Fixed.
Also, support the common extension of $ and \ in a FORMAT
as being equivalent to ADVANCE=NO.
Differential Revision: https://reviews.llvm.org/D105046
With derived type description tables now available to the
runtime library, it is possible to implement the concept
of "child" I/O statements in the runtime and use them to
convert instances of derived type I/O data transfers into
calls to user-defined subroutines when they have been specified
for a type. (See Fortran 2018, subclauses 12.6.4.8 & 13.7.6).
- Support formatted, list-directed, and NAMELIST
transfers to internal parent units; support these, and unformatted
transfers, for external parent units.
- Support nested child defined derived type I/O.
- Parse DT'foo'(v-list) FORMAT data edit descriptors and passes
their strings &/or v-list values as arguments to the defined
formatted I/O routines.
- Fix problems with this feature encountered in semantics and
FORMAT valiation during development and end-to-end testing.
- Convert typeInfo::SpecialBinding from a struct to a class
after adding a member function.
Differential Revision: https://reviews.llvm.org/D104930
Add InputNamelist and OutputNamelist as I/O data transfer APIs
to be used with internal & external list-directed I/O; delete the
needless original namelist-specific Begin... calls.
Implement NAMELIST output and input; add basic tests.
Differential Revision: https://reviews.llvm.org/D101931
What the Fortran standard calls "preconnected" external I/O units
might not be known to be connected to unformatted or formatted files
until the first I/O data transfer statement is executed.
Support this deferred determination by representing the flag as
a tri-state Boolean and adapting its points of use.
Differential Revision: https://reviews.llvm.org/D101929
Debug the input path for READ statements with END= labels;
don't emit errors when the program can handle them.
BeginReadingRecord() member functions have been made
"bool" for more convenient handling of error cases,
and some code in IoErrorHandler has been cleaned up.
Differential Revision: https://reviews.llvm.org/D100421
Peter Klausler