Commit Graph

16 Commits

Author SHA1 Message Date
Andrzej Warzynski 4f21e6aedd [flang][nfc] Tweak the FrontendAction class
This patch refactors the `FrontendAction` class. It merely moves code
around so that re-using it is easier. No new functionality is
introduced.

1. Three new member methods are introduced: `RunPrescan`, `RunParse`,
`RunSemanticChecks`.
2. The following free functions are re-implemented as member methods:
  * `reportFatalSemanticErrors`
  * `reportFatalScanningErrors`
  * `reportFatalParsingErrors`
  * `reportFatalErrors`
`reportFatalSemanticErrors` is updated to resemble the other error
reporting functions and to make the API more consistent.
3. The `BeginSourceFileAction` methods are simplified and the unused
input argument is deleted.

Differential Revision: https://reviews.llvm.org/D108130
2021-08-17 07:36:44 +00:00
Stuart Ellis f52fc591fa [flang][driver] Add support for Frontend Plugins
Introducing a plugin API and a simple HelloWorld Plugin example.
This patch adds the `-load` and `-plugin` flags to frontend driver and
the code around using custom frontend actions from within a plugin
shared library object.

It also adds to the Driver-help test to check the help option with the
updated driver flags.

Additionally, the patch creates a plugin-example test to check the
HelloWorld plugin example runs correctly. As part of this, a new CMake
flag (`FLANG_BUILD_EXAMPLES`) is added to allow the example to be built
and for the test to run.

This Plugin API has only been tested on Linux.

Reviewed By: awarzynski

Differential Revision: https://reviews.llvm.org/D106137
2021-08-12 11:42:16 +01:00
Andrzej Warzynski 23d4c4f3fb [flang][nfc] Fix variable names in `FrontendOptions` & `PreprocessorOptions`
As all member variables in `FrontendOptions` and `PreprocessorOptions`
are public, we should be naming them as `variable` rather than
`variable_` [1]. This patch fixes that.

Also, `FrontendOptions` & `PreprocessorOptions` are re-defined as a
structs rather than classes (all fields are meant to be public).

[1]
https://github.com/llvm/llvm-project/blob/main/flang/docs/C%2B%2Bstyle.md#naming

Differential Revision: https://reviews.llvm.org/D107062
2021-08-02 10:08:31 +00:00
Andrzej Warzynski c1f068b8f1 [flang] Revert "PoC for Flang Driver Plugins"
This patch has not been reviewed and was commited by accident.

This reverts commit 788a5d4afe.
2021-07-01 08:27:31 +00:00
Stuart Ellis 788a5d4afe PoC for Flang Driver Plugins 2021-07-01 08:10:40 +00:00
Andrzej Warzynski b83a4450c2 [flang][driver] Add support for `-cpp/-nocpp`
This patch adds support for the `-cpp` and `-nocpp` flags. The
implemented semantics match f18 (i.e. the "throwaway" driver), but are
different to gfortran. In Flang the preprocessor is always run. Instead,
`-cpp/-nocpp` are used to control whether predefined and command-line
preprocessor macro definitions are enabled or not. In practice this is
sufficient to model gfortran`s `-cpp/-nocpp`.

In the absence of `-cpp/-nocpp`, the driver will use the extension of
the input file to decide whether to include the standard macro
predefinitions. gfortran's documentation [1] was used to decide which
file extension to use for this.

The logic mentioned above was added in FrontendAction::BeginSourceFile.
That's relatively late in the driver set-up, but this roughly where the
name of the input file becomes available. The logic for deciding between
fixed and free form works in a similar way and was also moved to
FrontendAction::BeginSourceFile for consistency (and to reduce
code-duplication).

The `-cpp/-nocpp` flags are respected also when the input is read from
stdin. This is different to:
   * gfortran (behaves as if `-cpp` was used)
   * f18 (behaves as if `-nocpp` was used)

Starting with this patch, file extensions are significant and some test
files had to be renamed to reflect that. Where possible, preprocessor
tests were updated so that they can be shared between `f18` and
`flang-new`. This was implemented on top of adding new test for
`-cpp/-nocpp`.

[1] https://gcc.gnu.org/onlinedocs/gcc/Overall-Options.html

Reviewed By: kiranchandramohan

Differential Revision: https://reviews.llvm.org/D99292
2021-04-07 13:01:52 +00:00
Andrzej Warzynski d06e94031b [flang][driver] Add PrescanAction frontend action (nfc)
This new action encapsulates all actions that require the prescanner to
be run before proceeding with other processing. By adding this new
action, we are better equipped to control which actions _do_ run the
prescanner and which _do not_.

The following actions that require the prescanner are refactored to
inherit from `PrescanAction`:
  * `PrintPreprocessedAction`
  * `ParseSyntaxOnlyAction` .

New virtual method is introduced to facilitate all this:
  * `BeginSourceFileAction`
Like in Clang, this method is run inside `BeginSourceFile`. In other
words, it is invoked before `ExecuteAction` for the corresponding
frontend action is run. This method allows us to:
  * carry out any processing that is always required by the action (e.g.
    run the prescanner)
  * fine tune the settings/options on a file-by-file basis (e.g. to
    decide between fixed-form and free-form based on file extension)

This patch implements non-functional-changes.

Reviewed By: FarisRehman

Differential Revision: https://reviews.llvm.org/D95464
2021-02-04 14:23:33 +00:00
Andrzej Warzynski 760e6c4ce5 [flang][driver] Disallow non-existent input files in the frontend driver
This patch adds a check that verifies that the input file used when
calling the frontend driver (i.e. `flang-new -fc1`) actually exists.
This was not required for the compiler driver, `flang-new`, as that's
already handled in libclangDriver.

Once all input/output file management is moved to the driver, we should
also check that for input from `stdin` the corresponding file descriptor
was successfully acquired.

This patch also makes sure that the default action in the frontend is
`ParseSyntaxOnly`. This is consistent with Clang. Before this change
`flang-new -fc1` would do nothing, which makes testing changes like the
one introduced here a bit tricky.

Reviewed By: SouraVX

Differential Revision: https://reviews.llvm.org/D95127
2021-02-02 10:03:45 +00:00
Andrzej Warzynski aba24c1580 [flang][driver] Move fixed/free from detection out of FrontendAction API
All Fortran options should be set in `CompilerInstance` (via its
`CompilerInvocation`) before any of `FrontendAction` is entered -
that's one of the tasks of the driver. However, this is a bit tricky
with fixed and free from detection introduced in
https://reviews.llvm.org/D94228.

Fixed-free form detection needs to happen:
  * before any frontend action (we need to specify `isFixedForm` in
    `Fortran::parser::Options` before running any actions)
  * separately for every input file (we might be compiling multiple
    Fortran files, some in free form, some in fixed form)
In other words, we need this to happen early (before any
`FrontendAction`), but not too early (we need to know what the current
input file is). In practice, `isFixedForm` can only be set later
than other options (other options are inferred from compiler flags). So
we can't really set all of them in one place, which is not ideal.

All changes in this patch are NFCs (hence no new tests). Quick summary:
  * move fixed/free form detection from `FrontendAction::ExecuteAction` to
    `CompilerInstance::ExecuteAction`
  * add a bool flag in `FrontendInputFile` to mark a file as fixed/free
    form
  * updated a few comments

Differential Revision: https://reviews.llvm.org/D95042
2021-01-21 16:57:22 +00:00
Andrzej Warzynski cea3abc26f [flang][driver] Move isFixedFormSuffix and isFreeFormSuffix to flangFrontend
isFixedFormSuffix and isFreeFormSuffix should be defined in
flangFrontend rather than flangFrontendTool library. That's for 2
reasons:
  * these methods are used in flangFrontend rather than flangFrontendTool
  * flangFrontendTool depends on flangFrontend

As mentioned in the post-commit review for D94228, without this change
shared library builds fail.

Differential Revision: https://reviews.llvm.org/D94968
2021-01-19 17:47:40 +00:00
Faris Rehman 443d6957ca [flang][driver] Add support for fixed form detection
Currently the new flang driver always runs in free form mode. This patch
adds support for fixed form mode detection based on the file extensions.

Like `f18`, `flang-new` will treat files ending with ".f", ".F" and
".ff" as fixed form. Additionally, ".for", ".FOR", ".fpp" and ".FPP"
file extensions are recognised as fixed form files. This is consistent
with gfortran [1]. In summary, files with the following extensions are
treated as fixed-form:
  * ".f", ".F", ".ff", ".for", ".FOR", ".fpp", ".FPP"

For consistency with flang/test/lit.cfg.py and f18, this patch also adds
support for the following file extensions:
  * ".ff", ".FOR", ".for", ".ff90", ".fpp", ".FPP"
This is added in flang/lib/Frontend/FrontendOptions.cpp. Additionally,
the following extensions are included:
  * ".f03", ".F03", ".f08", ".F08"
This is for compatibility with gfortran [1] and other popular Fortran
compilers [2].

NOTE: internally Flang will only differentiate between fixed and free
form files. Currently Flang does not support switching between language
standards, so in this regard file extensions are irrelevant. More
specifically, both `file.f03` and `file.f18` are represented with
`Language::Fortran` (as opposed to e.g. `Language::Fortran03`).

Summary of changes:
- Set Fortran::parser::Options::sFixedForm according to the file type
- Add isFixedFormSuffix and isFreeFormSuffix helper functions to
  FrontendTool/Utils.h
- Change FrontendOptions::GetInputKindForExtension to support the missing
  file extensions that f18 supports and some additional ones
- FrontendActionTest.cpp is updated to make sure that the test input is
  treated as free-form

[1] https://gcc.gnu.org/onlinedocs/gfortran/GNU-Fortran-and-GCC.html
[2] https://github.com/llvm/llvm-project/blob/master/flang/docs/OptionComparison.md#notes

Differential Revision: https://reviews.llvm.org/D94228
2021-01-19 12:58:01 +00:00
Andrzej Warzynski fa1e543e0b [flang][driver] Update error messages (nfc)
As per Flang's coding guidelines
(flang/docs/C++style.md#error-messages):
```
Messages should start with a capital letter.
```

This patch updates error messages in the driver (new and old) so that
they conform with the guideline above.

This change was suggested in one of the recent reviews:
https://reviews.llvm.org/D93712. It felt like this deserved a dedicated
patch, so sending it separately.
2021-01-06 10:41:27 +00:00
Andrzej Warzynski e49dc2981c [flang][driver] Add checks for errors from `Prescan` and `Parse`
If either `Prescan` or `Parse` generate any fatal errors, the new driver
will:
  * report it (i.e. issue an error diagnostic)
  * exit early
  * return non-zero exit code
This behaviour is consistent with f18 (i.e. the old driver).

Reviewed By: sameeranjoshi

Differential Revision: https://reviews.llvm.org/D93712
2021-01-06 10:19:44 +00:00
Caroline Concatto d28de0d7f2 [Flang][Driver] Add PrintPreprocessedInput FrontendAction (`flang-new -E`)
This patch implements the first frontend action for the Flang parser (i.e.
Fortran::parser). This action runs the preprocessor and is invoked with the
`-E` flag. (i.e. `flang-new -E <input-file>). The generated output is printed
to either stdout or the output file (specified with `-` or `-o <output-file>`).

Note that currently there is no mechanism to map options for the
frontend driver (i.e. Fortran::frontend::FrontendOptions) to options for
the parser (i.e. Fortran::parser::Options). Instead,
Frotran::parser::options are hard-coded to:

```
std::vector<std::string> searchDirectories{"."s};
searchDirectories = searchDirectories;
isFixedForm = false;
_encoding(Fortran::parser::Encoding::UTF_8);
```

These default settings are compatible with the current Flang driver. Further
work is required in order for CompilerInvocation to read and map
clang::driver::options to Fortran::parser::options.

Co-authored-by: Andrzej Warzynski <andrzej.warzynski@arm.com>

Differential Revision: https://reviews.llvm.org/D88381
2020-11-02 14:03:35 +00:00
Andrzej Warzynski 9ffb5b0469 [flang][driver] Rename the accessors/mutators (NFC)
As per point 3 in [1]:

```
Accessor member functions are named with the non-public data member's
name, less the trailing underscore.  Mutator member functions are named
set_...
```

Originally we just followed the LLVM's style, which is incompatible with
Flang. This patch renames the accessors and mutators accordingly.

`getDiagnostics` and `GetDiagnostics` are replaced with one accessor:
`diagnostics`. `SetDiagnostics` was neither implemented nor used, so
it's deleted.

[1] https://github.com/llvm/llvm-project/blob/master/flang/docs/C++style.md#naming

Differential Revision: https://reviews.llvm.org/D90300
2020-11-02 10:55:13 +00:00
Caroline Concatto 4c5906cffd [Flang][Driver] Add infrastructure for basic frontend actions and file I/O
This patch introduces the dependencies required to read and manage input files
provided by the command line option. It also adds the infrastructure to create
and write to output files. The output is sent to either stdout or a file
(specified with the `-o` flag).

Separately, in order to be able to test the code for file I/O, it adds
infrastructure to create frontend actions. As a basic testable example, it adds
the `InputOutputTest` FrontendAction. The sole purpose of this action is to
read a file from the command line and print it either to stdout or the output
file.  This action is run by using the `-test-io` flag also introduced in this
patch (available for `flang-new` and `flang-new -fc1`). With this patch:
```
flang-new -test-io input-file.f90
```
will read input-file.f90 and print it in the output file.

The `InputOutputTest` frontend action has been introduced primarily to
facilitate testing. It is hidden from users (i.e. it's only displayed with
`--help-hidden`). Currently Clang doesn’t have an equivalent action.

`-test-io` is used to trigger the InputOutputTest action in the Flang frontend
driver. This patch makes sure that “flang-new” forwards it to “flang-new -fc1"
by creating a preprocessor job. However, in Flang.cpp, `-test-io` is passed to
“flang-new -fc1” without `-E`. This way we make sure that the preprocessor is
_not_ run in the frontend driver. This is the desired behaviour: `-test-io`
should only read the input file and print it to the output stream.

co-authored-by: Andrzej Warzynski <andrzej.warzynski@arm.com>

Differential Revision: https://reviews.llvm.org/D87989
2020-10-24 14:58:32 +01:00