Commit Graph

101 Commits

Author SHA1 Message Date
Andrzej Warzynski 1e462fafdf [flang][driver] Switch to the MLIR coding style in the driver (nfc)
This patch re-factors the driver code in LLVM Flang (frontend +
compiler) to use the MLIR style. For more context, please see:
https://discourse.llvm.org/t/rfc-coding-style-in-the-driver/

Most changes here are rather self-explanatory. Accessors are renamed to
be more consistent with the rest of LLVM (e.g. allSource -->
getAllSources). Additionally, MLIR clang-tidy files are added in the
affected directories.

clang-tidy and clang-format files were copied from MLIR. Small
additional changes are made to silence clang-tidy/clang-format
warnings.

[1] https://mlir.llvm.org/getting_started/DeveloperGuide/

Differential Revision: https://reviews.llvm.org/D125007
2022-05-14 10:27:06 +00:00
Andrzej Warzynski c12ef70d2b [flang][driver] Add missing parentheses in an assert
The assert in https://reviews.llvm.org/D124665 was missing parentheses,
which triggered a warning in GCC (verified with GCC 11). As `-Werror` is
on by default in FLang, that triggered build errors, see e.g. [1].

The fix is rather straightforward, so I am sending this without a
review.

[1] https://lab.llvm.org/buildbot/#/builders/160/builds/7016

Differential Revision: https://reviews.llvm.org/D125027
2022-05-05 18:02:30 +00:00
Andrzej Warzynski b9f3b7f89a [flang][driver] Add support for consuming LLVM IR/BC files
This change makes sure that Flang's driver recognises LLVM IR and BC as
supported file formats. To this end, `isFortran` is extended and renamed
as `isSupportedByFlang` (the latter better reflects the new
functionality).

New tests are added to verify that the target triple is correctly
overridden by the frontend driver's default value or the value specified
with `-triple`. Strictly speaking, this is not a functionality that's
new in this patch (it was added in D124664). This patch simply enables
us to write such tests and hence I'm including them here.

Differential Revision: https://reviews.llvm.org/D124667
2022-05-05 15:11:50 +00:00
Andrzej Warzynski bb177edc44 [flang][driver] Re-organise the code-gen actions (nfc)
All frontend actions that generate code  (MLIR, LLVM IR/BC,
Assembly/Object Code) are re-factored as essentially one action,
`CodeGenAction`, with minor specialisations. To facilate all this,
`CodeGenAction` is extended to hold `TargetMachine` and backend action
type (MLIR vs LLVM IR vs LLVM BC vs Assembly vs Object Code).

`CodeGenAction` is no longer a pure abstract class and the
corresponding `ExecuteAction` is implemented so that it covers all use
cases. All this allows a much better code re-use.

Key functionality is extracted into some helpful hooks:
  * `SetUpTargetMachine`
  * `GetOutputStream`
  * `EmitObjectCodeHelper`
  * `EmitBCHelper`
I hope that this clarifies the overall structure. I suspect that we may
need to revisit this again as the functionality grows in complexity.

Differential Revision: https://reviews.llvm.org/D124665
2022-05-05 14:05:06 +00:00
Andrzej Warzynski 02fb5b771d [flang][driver] Define the default frontend driver triple
*SUMMARY*
Currently, the frontend driver assumes that a target triple is either:
  * provided by the frontend itself (e.g. when lowering and generating
    code),
  * specified through the `-triple/-target` command line flags.

If `-triple/-target` is not used, the frontend will simply use the host
triple.

This is going to be insufficient when e.g. consuming an LLVM IR file
that has no triple specified (reading LLVM files is WIP, see D124667).
We shouldn't require the triple to be specified via the command line in
such situation. Instead, the frontend driver should contain a good
default, e.g.  the host triple.

This patch updates Flang's `CompilerInvocation` to do just that, i.e.
defines its default target triple. Similarly to Clang:
 * the default `CompilerInvocation` triple is set as the host triple,
 * the value specified with `-triple` takes precedence over the frontend
   driver default and the current module triple,
 * the frontend driver default takes precedence over the module triple.

*TESTS*
This change requires 2 unit tests to be updated. That's because relevant
frontend actions are updated to assume that there's always a valid
triple available in the current `CompilerInvocation`. This update is
required because the unit tests bypass the regular `CompilerInvocation`
set-up (in particular, they don't call
`CompilerInvocation::CreateFromArgs`). I've also taken the liberty to
disable the pre-precossor formatting in the affected unit tests as well
(it is not required).

No new tests are added. As `flang-new -fc1` does not support consuming
LLVM IR files just yet, it is not possible to compile an LLVM IR file
without a triple. More specifically, atm all LLVM IR files are generated
and stored internally and the driver makes sure that these contain a
valid target triple. This is about to change in D124667 (which adds
support for reading LLVM IR/BC files) and that's where tests for
exercising the default frontend driver triple will be added.

*WHAT DOES CLANG DO?*
For reference, the default target triple for Clang's
`CompilerInvocation` is set through option marshalling infra [1] in
Options.td. Please check the definition of the `-triple` flag:
```
def triple : Separate<["-"], "triple">,
  HelpText<"Specify target triple (e.g. i686-apple-darwin9)">,
  MarshallingInfoString<TargetOpts<"Triple">, "llvm::Triple::normalize(llvm::sys::getDefaultTargetTriple())">,
  AlwaysEmit, Normalizer<"normalizeTriple">;
```
Ideally, we should re-use the marshalling infra in Flang.

[1] https://clang.llvm.org/docs/InternalsManual.html#option-marshalling-infrastructure

Differential Revision: https://reviews.llvm.org/D124664
2022-05-04 12:01:53 +00:00
Andrzej Warzynski d902dd011c [flang][driver] NFC: Make code more in line with LLVM style
This patch basically implements [1] in ExecuteCompilerInvocation.cpp. It
also:
  * replaces `CreateFrontendBaseAction` with `CreateFrontendAction`
    (only one method is needed ATM, this change removes the extra
    indirection)
  * removes `InvalidAction` from the `ActionKind` enum (I don't think it
    adds much and keeping it would mean adding a new void case in
    `CreateFrontendAction`)
  * sets the default frontend action in FrontendOptions.h to
    `ParseSyntaxOnly` (note that this is still overridden independently
    in `ParseFrontendArg` in CompilerInvocation.cpp)

No new functionality is added, hence no tests.

[1] https://llvm.org/docs/CodingStandards.html#don-t-use-default-labels-in-fully-covered-switches-over-enumerations

Differential Revision: https://reviews.llvm.org/D124245
2022-04-27 09:20:07 +00:00
Andrzej Warzynski 2186a4aea0 [flang] Make the plugin API independent of the driver internals
This patch adds a few new member methods in the `PluginParseTreeAction`
frontend action base class. With these new methods, the plugin API
becomes independent of the driver internals. In particular, plugin
writers no longer require the `CompilerInstance.h` header file to access
various driver data structures (instead, they can use newly added
hooks).

This change is desirable as `CompilerInstance.h` includes various
headers from Clang (both explicitly and implicitly). Some of these
header files are generated at build time (through TableGen) and
including them creates a dependency on some of Clang's build targets.
However, plugins in Flang should not depend on Clang build targets.

Note that plugins might still work fine most of the time, even without
this change and without adding Clang build targets as dependency in
plugin's CMake definition. Indeed, these Clang build targets are often
generated early in the build process. However, that's not guaranteed and
we did notice that on occasions plugins would fail to build.

Differential Revision: https://reviews.llvm.org/D120999
2022-04-22 09:18:04 +00:00
Andrzej Warzynski 6c93e1d329 [flang][driver] Add support for `-mmlir`
The semantics of `-mmlir` are identical to `-mllvm`. The only notable
difference is that `-mmlir` options should be forwarded to MLIR rather
than LLVM.

Note that MLIR llvm::cl options are lazily constructed on demand (see
the definition of options in PassManagerOptions.cpp). This means that:
  * MLIR global options are only visible when explicitly initialised and
    displayed only when using `-mmlir --help`,
  * Flang and LLVM global options are always visible and displayed when
    using either `-mllvm -help` or `-mmlir --help`.

In other words, `-mmlir --help` is a superset of `-mllvm --help`. This is not
ideal, but we'd need to refactor all option definitions in Flang and
LLVM to improve this. I suggesting leaving this for later.

Differential Revision: https://reviews.llvm.org/D123297
2022-04-14 09:40:31 +00:00
Andrzej Warzynski 8de6cb1297 [flang] Fix DYLIB builds
https://reviews.llvm.org/D123211 broke builds that set both
`LLVM_BUILD_LLVM_DYLIB` and `LLVM_LINK_LLVM_DYLIB` (see [1]). This patch
fixes that.

The build failure was caused by the fact that the LLVMPasses library,
which is an LLVM "component", was listed directly as link-time
dependency. Instead, one should use `LINK_COMPONENTS` in CMake files. I
made an identical mistake recently and then subsequently fixed it in
https://reviews.llvm.org/D121461 - please visit that revision for more
detail.

I'm merging this without a review. The change is straightforward, we
recently discussed it and I was able to confirm locally that it fixes
the build issue.

[1] https://lab.llvm.org/buildbot/#/builders/177/builds/4619
2022-04-14 08:58:34 +00:00
Andrzej Warzynski 6d3224d93f [flang][nfc] Simplify TargetMachine initialisation 2022-04-13 10:49:24 +00:00
Andrzej Warzynski dd56939a4b [flang][driver] Add support for generating LLVM bytecode files
Support for generating LLVM BC files is added in Flang's compiler and
frontend drivers. This requires the `BitcodeWriterPass` pass to be run
on the input LLVM IR module and is implemented as a dedicated frontend
aciton. The new functionality as seen by the user (compiler driver):
```
flang-new -c -emit-llvm file.90
```
or (frontend driver):
```
flang-new -fc1 -emit-llvm-bc file.f90
```

The new behaviour is consistent with `clang` and `clang -cc1`.

Differential Revision: https://reviews.llvm.org/D123211
2022-04-13 10:19:56 +00:00
Fangrui Song 30b1c1f23d [Driver] Simplify -f[no-]diagnostics-color handling. NFC
Make them aliases for -f[no-]color-diagnostics.
2022-04-10 01:07:44 -07:00
Andrzej Warzynski dda366ed37 [flang][cmake] Make CMake copy "omp_lib.h" into the build directory
Any header or module file in the Flang source directory is of no use to
the compiler unless it is copied into the build directory. Indeed, all
compiler search paths are relative to the compiler executable (flang-new
in our case). Hence, "omp_lib.h" should be copied into the build
directory alongside other compiler-provided files that can be "included"
(header files) or "used" (module files).

For now, "omp_lib.h" is copied into "<build-dir>/include/flang/OpenMP".
We may decide to change this in future. For example, Clang copies a
bunch of runtime headers into “<build-dir>/lib/clang/<version-number>”.
We could also consider using a similar header from a different
sub-project.

Flang's driver search path is updated accordingly. A rule for
"installing" the "omp_lib.h" header is _yet to be added_ (we will also
need to determine the suitable location for this).

Differential Revision: https://reviews.llvm.org/D122015
2022-04-05 08:25:26 +00:00
Andrzej Warzynski a7c08bcf77 [flang][driver] Add support for `-mllvm`
This option is added in both `flang-new` (the compiler driver) and
`flang-new -fc1` (the frontend driver). The semantics are consistent
with `clang` and `clang -cc1`.

As Flang does not run any LLVM passes when invoked with `-emit-llvm`
(i.e. `flang-new -S -emit-llvm <file>`), the tests use
`-S`/`-c`/`-emit-obj` instead. These options require an LLVM backend to
be run by the driver to generate the output (this makese `-mllvm`
relevant here).

Differential Revision: https://reviews.llvm.org/D121374
2022-03-16 10:41:04 +00:00
Andrzej Warzynski 85e2731aa3 [flang] Fix DYLIB builds
https://reviews.llvm.org/D120568 broke builds that set
both `LLVM_BUILD_LLVM_DYLIB` and `LLVM_LINK_LLVM_DYLIB`. This patch
fixes that.

The build failure was caused by the fact that some LLVM libraries (which
are also LLVM components) were listed directly as link-time dependencies
instead of using `LINK_COMPONENTS` in CMake files. This lead to a linker
invocation like this (simplified version to demonstrate the problem):
```
ld lib/libLLVM.so lib/libLLVMAnalysis.a lib/libLLVMTarget.a
```
That's problematic and unnecessary because `libLLVM.so` incorporates
`libLLVMAnalysis` and `libLLVMTarget`. A correct invocation would look
like this (`LLVM_LINK_LLVM_DYLIB` _is not_ set):
```
ld  lib/libLLVMAnalysis.a lib/libLLVMTarget.a
```
or this (`LLVM_LINK_LLVM_DYLIB` _is_ set):
```
ld lib/libLLVM.so
```

Differential Revision: https://reviews.llvm.org/D121461
2022-03-11 16:12:36 +00:00
Andrzej Warzynski 38101b4e95 [flang][driver] Add support for -S and implement -c/-emit-obj
This patch adds support for:
  * `-S` in Flang's compiler and frontend drivers,
and implements:
  * `-emit-obj` in Flang's frontend driver and `-c` in Flang's compiler
    driver (this is consistent with Clang).
(these options were already available before, but only as placeholders).
The semantics of these options in Clang and Flang are identical.

The `EmitObjAction` frontend action is renamed as `BackendAction`. This
new name more accurately reflects the fact that this action will
primarily run the code-gen/backend pipeline in LLVM. It also makes more
sense as an action implementing both `-emit-obj` and `-S` (originally,
it was just `-emit-obj`).

`tripleName` from FirContext.cpp is deleted and, when a target triple is
required, `mlir::LLVM::LLVMDialect::getTargetTripleAttrName()` is used
instead. In practice, this means that `fir.triple` is replaced with
`llvm.target_triple`. The former was effectively ignored. The latter is
used when lowering from the LLVM dialect in MLIR to LLVM IR (i.e. it's
embedded in the generated LLVM IR module). The driver can then re-use
it when configuring the backend. With this change, the LLVM IR files
generated by e.g. `tco` will from now on contain the correct target
triple.

The code-gen.f90 test is replaced with code-gen-x86.f90 and
code-gen-aarch64.f90. With 2 seperate files we can verify that
`--target` is correctly taken into account. LIT configuration is updated
to enable e.g.:
```
! REQUIRES: aarch64-registered-target
```

Differential Revision: https://reviews.llvm.org/D120568
2022-03-09 15:48:09 +00:00
Andrzej Warzynski 8321579b28 [flang][driver] Add support for `-debug-dump-pft`
This patch adds support for dumping the pre-FIR tree in `flang-new
-fc1`, i.e. Flang's frontend driver. This flag is functionally identical
to `-pft-test` in `bbc` and semantically similar to
`-fdebug-dump-parse-tree` from `flang-new -fc1`.

Differential Revision: https://reviews.llvm.org/D121198
2022-03-08 19:21:58 +00:00
Andrzej Warzynski b383b17bf7 [flang][nfc] Update the CMake dependencies for `flangFrontend`
The "FrontendActions.cpp" file (which is one of the source files for the
`flangFrontend` library) includes "Passes.h.inc" (indirectly, via
"CLOptions.inc"). This file is generated alongside other TableGen
outputs from the `FIROptTransformsPassIncGen` CMake target. This patch
adds `FIROptTransformsPassIncGen` to the list of build dependencies for
`flangFrontend`.

The lack of this dependency might cause non-determinstic build failures,
e.g. https://lab.llvm.org/buildbot/#/builders/160/builds/6210.

Differential Revision: https://reviews.llvm.org/D121218
2022-03-08 17:19:32 +00:00
Andrzej Warzynski bbcc0f6006 [flang] Fix standalone builds
In dd875dd88b I added a missing MLIR
dependency in Flang. However, that particular CMake target is not
exported as something available to standalone builds. In this patch is
switch to `MLIRIR` instead, which depends on
`MLIRBuiltinAttributeInterfacesIncGen` - the missing dependency added
previously.

Differential Revision: https://reviews.llvm.org/D120986
2022-03-04 13:05:44 +00:00
Andrzej Warzynski dd875dd88b [flang][nfc] Add missing build dependency
Two buildbots have started failing recently:
* https://lab.llvm.org/buildbot/#/builders/181/builds/3894
* https://lab.llvm.org/buildbot/#/builders/191/builds/3908

Build error:
```
In file included from /home/tcwg-buildbot/worker/flang-aarch64-rel-assert/llvm-project/flang/examples/FlangOmpReport/FlangOmpReport.cpp:21:
In file included from /home/tcwg-buildbot/worker/flang-aarch64-rel-assert/llvm-project/flang/include/flang/Frontend/FrontendActions.h:15:
In file included from /home/tcwg-buildbot/worker/flang-aarch64-rel-assert/llvm-project/llvm/../mlir/include/mlir/IR/BuiltinOps.h:16:
In file included from /home/tcwg-buildbot/worker/flang-aarch64-rel-assert/llvm-project/llvm/../mlir/include/mlir/IR/FunctionInterfaces.h:17:
In file included from /home/tcwg-buildbot/worker/flang-aarch64-rel-assert/llvm-project/llvm/../mlir/include/mlir/IR/BuiltinTypes.h:12:
/home/tcwg-buildbot/worker/flang-aarch64-rel-assert/llvm-project/llvm/../mlir/include/mlir/IR/BuiltinAttributeInterfaces.h:279:10: fatal error: 'mlir/IR/BuiltinAttributeInterfaces.h.inc' file not found
         ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1 error generated.
```

I have not been able to reproduce locally, but from this log it is clear
that the rule for `flangFrontend` is missing the
`MLIRBuiltinAttributeInterfacesIncGen` dependency from MLIR.  I couldn't
identify a breaking commit. I suspect that until now we have simply been
"lucky" and that dependency just happened to be built before
`flangFrontend`.

I am sending this without a review - the change is rather
straightforward and the only way to verify it is to make the buildbots
test it.
2022-03-03 16:39:58 +00:00
Andrzej Warzynski 2e9439e489 [flang][driver] Add support for `--target`/`--triple`
This patch adds support for:
  * `--target` in the compiler driver (`flang-new`)
  * `--triple` in the frontend driver (`flang-new -fc1`)
The semantics of these flags are inherited from `clangDriver`, i.e.
consistent with `clang --target` and `clang -cc1 --triple`,
respectively.

A new structure is defined, `TargetOptions`, that will hold various
Frontend options related to the target. Currently, this is mostly a
placeholder that contains the target triple. In the future, it will be
used for storing e.g. the CPU to tune for or the target features to
enable.

Additionally, the following target/triple related options are enabled
[*]: `-print-effective-triple`, `-print-target-triple`. Definitions in
Options.td are updated accordingly and, to facilated testing,
`-emit-llvm` is added to the list of options available in `flang-new`
(previously it was only enabled in `flang-new -fc1`).

[*] These options were actually available before (like all other options
defined in `clangDriver`), but not included in `flang-new --help`.
Before this change, `flang-new` would just use `native` for defining the
target, so these options were of little value.

Differential Revision: https://reviews.llvm.org/D120246
2022-02-25 09:38:10 +00:00
Andrzej Warzynski 16a91a1cbe [flang][driver] Make `flang-new` always generate run-time type info
Currently, the driver generates the tables with "run-time type
information for derived types" only when specific actions are run.
However, the corresponding data might be required by the subsequent
compilation stages (e.g. lowering, code-gen) and should be generated
unconditionally. Note that this is only possible once the semantic
checks have been run.

Note that when generating these tables, extra semantic errors might be
generated. The driver will always report these and in most cases such
semantic errors will cause the driver to exit immediately. The only
exception are actions inheriting from `PrescanAndSemaDebugAction`.
Currently, there's only one such action: `DebugDumpAllAction`
(corresponds to `-fdebug-dump-all` command-line flag). I've updated the
comments for this action to clarify this.

This change will mostly affect lowering, which currently is only
available for most basic examples (e.g. empty programs). I wasn't able
to find a working case that would demonstrate the new behaviour. I
hope that this change is straightforward enough and am submitting it
without a test.

Differential Revision: https://reviews.llvm.org/D120051
2022-02-23 10:08:03 +00:00
Andrzej Warzynski e993b20c04 [flang][driver] Add support for `-emit-llvm`
This patch adds support for the `-emit-llvm` option in the frontend
driver (i.e. `flang-new -fc1`). Similarly to Clang, `flang-new -fc1
-emit-llvm file.f` will generate a textual LLVM IR file.

Depends on D118985

Differential Revision: https://reviews.llvm.org/D119012
2022-02-17 12:13:03 +00:00
Andrzej Warzynski 69c3309d45 [flang][driver] Add support for `-emit-mlir`
This patch adds support for generating MLIR files in Flang's frontend
driver (i.e. `flang-new -fc1`). `-emit-fir` is added as an alias for
`-emit-mlir`. We may want to decide to split the two in the future.

A new parent class for code-gen frontend actions is introduced:
`CodeGenAction`. We will be using this class to encapsulate logic shared
between all code-generation actions, but not required otherwise. For
now, it will:
 * run prescanning, parsing and semantic checks,
 * lower the input to MLIR.
`EmitObjAction` is updated to inherit from this class. This means that
the behaviour of `flang-new -fc1 -emit-obj` is also updated (previously,
it would just exit immediately). This change required
`flang/test/Driver/syntax-only.f90` to be updated.

For `-emit-fir`, a specialisation of `CodeGenAction` is introduced:
`EmitMLIRAction`. The key logic for this class is implemented in
`EmitMLIRAction::ExecuteAction`.

Differential Revision: https://reviews.llvm.org/D118985
2022-02-09 08:35:48 +00:00
Peter Klausler 52a1346b78 [flang] Distinguish intrinsic from non-intrinsic modules
For "USE, INTRINSIC", search only for intrinsic modules;
for "USE, NON_INTRINSIC", do not recognize intrinsic modules.
Allow modules of both kinds with the same name to be used in
the same source file (but not in the same scoping unit, a
constraint of the standard that is now enforced).

The symbol table's scope tree now has a single instance of
a scope with a new kind, IntrinsicModules, whose children are
the USE'd intrinsic modules (explicit or not).  This separate
"top-level" scope is a child of the single global scope and
it allows both intrinsic and non-intrinsic modules of the same
name to exist in the symbol table.  Intrinsic modules' scopes'
symbols now have the INTRINSIC attribute set.

The search path directories need to make a distinction between
regular directories and the one(s) that point(s) to intrinsic
modules.  I allow for multiple intrinsic module directories in
the second search path, although only one is needed today.

Differential Revision: https://reviews.llvm.org/D118631
2022-01-31 13:31:27 -08:00
Andrzej Warzynski 4606f838b2 [flang][driver][nfc] Fix capitalisation
As pointed out in https://reviews.llvm.org/D93401, some methods in the
Flang driver are named inconsistently. The driver strives to follow
Flang's C++ style [1] and this patch updates these methods accordingly.

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

Differential Revision: https://reviews.llvm.org/D118381
2022-01-31 10:36:18 +00:00
serge-sans-paille 5597ec2dc4 Include missing "llvm/Support/Path.h" in "flang/lib/Frontend/CompilerInvocation.cpp" 2022-01-21 17:05:49 +01:00
Andrzej Warzynski d18a9aeae9 [flang] Make the frontend driver error out when requesting multiple actions
With this change, the following invocations will be treated as errors
(multiple actions are specified):
```
$ flang-new -fc1 -E -fsyntax-only file.95
$ flang-new -fc1 -fsyntax-only -fdebug-dump-symbols file.95
```
In the examples above it is not clear whether it is `-fsyntax-only` or
the other action that is run (i.e. `-E` or `-fdebug-dump-symbols`). It
makes sense to disallow such usage. This should also lead to cleaner and
clearer tests (the `RUN` lines using `%flang_fc1` will only allow one
action).

This change means that `flang-new -fc1` and `clang -cc1` will behave
differently when multiple action options are specified. As frontend
drivers are mostly used by compiler developers, this shouldn't affect or
confuse the compiler end-users. Also, `flang-new` and `clang` remain
consistent.

Tests are updated accordingly. More specifically, I've made sure that
every test specifies only one action. I've also taken the opportunity to
simplify "multiple-input-files.f90" a bit.

Differential Revision: https://reviews.llvm.org/D111781
2021-12-17 10:05:28 +00:00
Peter Klausler 996ef895cd [flang] Add -fno-automatic, refine IsSaved()
This legacy option (available in other Fortran compilers with various
spellings) implies the SAVE attribute for local variables on subprograms
that are not explicitly RECURSIVE.  The SAVE attribute essentially implies
static rather than stack storage.  This was the default setting in Fortran
until surprisingly recently, so explicit SAVE statements & attributes
could be and often were omitted from older codes.  Note that initialized
objects already have an implied SAVE attribute, and objects in COMMON
effectively do too, as data overlays are extinct; and since objects that are
expected to survive from one invocation of a procedure to the next in static
storage should probably be explicit initialized in the first place, so the
use cases for this option are somewhat rare, and all of them could be
handled with explicit SAVE statements or attributes.

This implicit SAVE attribute must not apply to automatic (in the Fortran sense)
local objects, whose sizes cannot be known at compilation time.  To get the
semantics of IsSaved() right, the IsAutomatic() predicate was moved into
Evaluate/tools.cpp to allow for dynamic linking of the compiler.  The
redundant predicate IsAutomatic() was noticed, removed, and its uses replaced.

GNU Fortran's spelling of the option (-fno-automatic) was added to
the clang-based driver and used for basic sanity testing.

Differential Revision: https://reviews.llvm.org/D114209
2021-11-22 10:06:38 -08:00
Andrzej Warzynski 6f8ef1d6e8 [flang][driver] Add actions that execute despite semantic errors
This patch adds a new abstract class for frontend actions:
`PrescanAndSemaDebugAction`. It's almost identical to
`PrescanAndSemaAction`, but in the presence of semantic errors it does
not skip the corresponding `ExecuteAction` specialisation. Instead, it
runs it as if there were no semantic errors. This class is for developer
actions only (i.e.  front-end driver options).

The new behaviour does not affect the return code from `flang-new -fc1`
when the input file is semantically incorrect. The return code is
inferred from the number of driver diagnostics generated in
`CompilerInstance::ExecuteAction` and this patch does not change that.
More specifically, the semantic errors are still reported and hence the
driver is able to correctly report that the compilation has failed (with
a non-zero return code).

This new base class is meant for debug actions only and
`DebugDumpAllAction` is updated to demonstrate the new behaviour. With
this change, `flang-new -fc1 -fdebug-dump-all` dumps the parse tree and
symbols for all input files, regardless of whether any semantic errors
were found.

This patch addresses https://bugs.llvm.org/show_bug.cgi?id=52097.

Differential Revision: https://reviews.llvm.org/D111308
2021-10-11 11:52:05 +00:00
Andrzej Warzynski b41e86642e [flang][driver] Fix erroneous `&`
As pointed out by Valentin Clement in PR [1], we should be using `&&`
instead of `&`.

[1] https://github.com/flang-compiler/f18-llvm-project/pull/1113#discussion_r724321121

Differential Revision: https://reviews.llvm.org/D111395
2021-10-08 14:44:44 +00:00
Andrzej Warzynski 787c443a8d [flang] Refine output file generation
This patch cleans-up the file generation code in Flang's frontend
driver. It improves the layering between
`CompilerInstance::CreateDefaultOutputFile`,
`CompilerInstance::CreateOutputFile` and their various clients.

* Rename `CreateOutputFile` as `CreateOutputFileImpl` and make it
  private. This method is an implementation detail.
* Instead of passing an `std::error_code` out parameter into
  `CreateOutputFileImpl`, have it return Expected<>. This is a bit shorter
  and idiomatic LLVM.
* Make `CreateDefaultOutputFile` (which calls `CreateOutputFileImpl`)
  issue an error when file creation fails. The error code from
  `CreateOutputFileImpl` is used to generate a meaningful diagnostic
  message.
* Remove error reporting from `PrintPreprocessedAction::ExecuteAction`.
  This is only for cases when output file generation fails. This is
  handled in `CreateDefaultOutputFile` instead (see the previous point).
* Inline `AddOutputFile` into its only caller,
  `CreateDefaultOutputFile`.
* Switch from `lvm::buffer_ostream` to `llvm::buffer_unique_ostream>`
  for non-seekable output streams. This simplifies the logic in the driver
  and was introduced for this very reason in [1]
* Moke sure that the diagnostics from the prescanner when running `-E`
  (`PrintPreprocessedAction::ExecuteAction`) are printed before the actual
  output is generated.
* Update comments, add test.

NOTE: This patch relands [2]. As suggested by Michael Kruse in the
post-commit/post-revert review, I've added the following:
```
config.errc_messages = "@LLVM_LIT_ERRC_MESSAGES@"
```
in Flang's `lit.site.cfg.py.in`. This way, `%errc_ENOENT` in
output-paths.f90 gets the correct value on Windows as well as on Linux.

[1] https://reviews.llvm.org/D93260
[2] fd21d1e198

Reviewed By: ashermancinelli

Differential Revision: https://reviews.llvm.org/D108390
2021-08-21 15:18:48 +00:00
Andrzej Warzynski 316be03ff5 Revert "[flang] Refine output file generation"
This reverts commit fd21d1e198.

The test added in this patch [1] is failing on Windows and causing the
Windows BuildBot [2] to fail. I don't see any obvious way to fix this,
so reverting in order to investigate.

[1] llvm-project/flang/test/Driver/output-paths.f90
[2] https://lab.llvm.org/buildbot/#/builders/172/builds/2077
2021-08-20 09:16:11 +00:00
Andrzej Warzynski fd21d1e198 [flang] Refine output file generation
This patch refactors the file generation API in Flang's frontend driver.
It improves the layering between `CreateDefaultOutputFile`,
`CreateOutputFile` (`CompilerInstance` methods) and their various
clients.

List of changes:
* Rename `CreateOutputFile` as `CreateOutputFileImpl` and make it
private. This method is an implementation detail.
* Instead of passing an `std::error_code` out parameter into
`CreateOutputFileImpl`, have it return Expected<>. This is a bit shorter
and more idiomatic LLVM.
* Make `CreateDefaultOutputFile` (which calls `CreateOutputFileImpl`)
issue an error when file creation fails. The error code from
`CreateOutputFileImpl` is used to generate a meaningful diagnostic
message.
* Remove error reporting from `PrintPreprocessedAction::ExecuteAction`.
This is only for cases when output file generation fails. This is
handled in `CreateDefaultOutputFile` instead (see the previous point).
* Inline `AddOutputFile` into its only caller,
`CreateDefaultOutputFile`.
* Switch from `lvm::buffer_ostream` to `llvm::buffer_unique_ostream>`
for non-seekable output streams. This simplifies the logic in the driver
and was introduced for this very reason in [1]
* Moke sure that the diagnostics from the prescanner when running `-E`
(`PrintPreprocessedAction::ExecuteAction`) are printed before the actual
output is generated.
* Update comments, add test.

[1] https://reviews.llvm.org/D93260

Differential Revision: https://reviews.llvm.org/D108390
2021-08-20 06:46:44 +00:00
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
Andrzej Warzynski 265a9961d1 [flang][nfc] Move `Semantics` from `FrontendAction` to `CompilerInstance`
`CompilerInstance` is a more appropriate place for a key component of
the frontend like `Semantics`.

This change opens a path for us to introduce new frontend actions that
will also run semantics, but for which inheriting from
`PrescanAndSemaAction` wouldn't make much sense. For example, for
code-gen actions we plan to introduce a dedicate hierarchy of action
classes.

I've also added a doxyment for `CompilerInstance` to add a bit of
context for this change (and also make future refactoring more informed).
As `CompilerInstance` in Flang has been inspired by its counterpart in
Clang, this comment is roughly a verbatim copy of the comment in Clang
(with some adjustments from me). Credits to Daniel Dunbar for the great
design and the original comment.

Differential Revision: https://reviews.llvm.org/D108035
2021-08-15 09:33:07 +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
Asher Mancinelli dfce2909ee [flang] Lift -Werror checks into local functions
Lift checks for -Werror into local functions.

Reviewed By: awarzynski

Differential Revision: https://reviews.llvm.org/D101261
2021-08-06 12:43:19 -06:00
Andrzej Warzynski 7b73ca3043 [flang][driver] Delete `f18` (i.e. the old Flang driver)
This patch removes `f18`, a.k.a. the old driver. It is being replaced
with the new driver, `flang-new`, which has reached feature parity with
`f18` a while ago. This was discussed in [1] and also in [2].

With this change, `FLANG_BUILD_NEW_DRIVER` is no longer needed and is
also deleted. This means that we are making the dependency on Clang permanent
(i.e. it cannot be disabled with a CMake flag).

LIT set-up is updated accordingly. All references to `f18` or `f18.cpp`
are either updated or removed.

The `F18_FC` variable from the `flang` bash script is replaced with
`FLANG_FC`. The former is still supported for backwards compatibility.

[1] https://lists.llvm.org/pipermail/flang-dev/2021-June/000742.html
[2] https://reviews.llvm.org/D103177

Differential Revision: https://reviews.llvm.org/D105811
2021-08-05 12:57:15 +00:00
Andrzej Warzynski 55a9615599 [flang][driver] Refactor boolean options
For boolean options, e.g. `-fxor-operator`/`-fno-xor-operator`, we ought
to be using TableGen multi-classes. This way, we only have to write one
definition to have both forms auto-generated. This patch refactors all
of Flang's boolean options to use two new multi-classes:
`OptInFC1FFOption` and `OptOutFC1FFOption`. These multi-classes are
based on `OptInFFOption`/`OptOutFFOption`, respectively. I've also
simplified the processing of the updated options in
CompilerInvocation.cpp.

With the new approach, "empty" help text (i.e. no `HelpText`) is now
replaced with an empty string (i.e. HelpText<"">). When running
flang-new --help, that's considered as non-empty help messages, which is
then printed (that's controlled by `printHelp` from
llvm/lib/Option/OptTable.cpp). This means that with this patch,
flang-new --help will start printing e.g. -fno-backslash, even though
there is no actual help text to print for this option (apart from the
empty string ""). Tests are updated accordingly.

Note that with this patch, both `-fxor-operator` and `-fno-xor-operator`
(and other boolean options refactored here) remain available in
`flang-new` and `flang-new -fc1`. In this respect, nothing changes. In a
forthcoming patch, I will refine this so that `flang-new -fc1` only
accepts `-ffoo` (`OptInFC1FFOption`) or `-fno-foo` (`OptOutCC1FFOption`).

For clarity, `OptInFFOption`/`OptOutFFOption` are renamed as
`OptInCC1FFOption`/`OptOutCC1FFOption`, respectively. Otherwise, this is
an NFC from Clang's perspective.

Differential Revision: https://reviews.llvm.org/D105881
2021-08-05 10:20:47 +00:00
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
peter klausler 3338ef93b0 [flang] Produce proper "preprocessor output" for -E option
Rename the current -E option to "-E -Xflang -fno-reformat".

Add a new Parsing::EmitPreprocessedSource() routine to convert the
cooked character stream output of the prescanner back to something
more closely resembling output from a traditional preprocessor;
call this new routine when -E appears.

The new -E output is suitable for use as fixed form Fortran source to
compilation by (one hopes) any Fortran compiler.  If the original
top-level source file had been free form source, the output will be
suitable for use as free form source as well; otherwise there may be
diagnostics about missing spaces if they were indeed absent in the
original fixed form source.

Unless the -P option appears, #line directives are interspersed
with the output (but be advised, f18 will ignore these if presented
with them in a later compilation).

An effort has been made to preserve original alphabetic character case
and source indentation.

Add -P and -fno-reformat to the new drivers.

Tweak test options to avoid confusion with prior -E output; use
-fno-reformat where needed, but prefer to keep -E, sometimes
in concert with -P, on most, updating expected results accordingly.

Differential Revision: https://reviews.llvm.org/D106727
2021-07-30 15:13:56 -07:00
Andrzej Warzynski e77191c35e [flang][driver] Extend the `flang` bash script to act as a driver
Until now, `f18` would:
  1. Use Flang to unparse the input files
  2. Call an external Fortran compiler to compile the unparsed source
  files (generated in step 1)

With this patch, `f18` will stop after unparsing the input source files,
i.e. step 1 above. The `flang` bash script will take care of step 2,
i.e. calling an external Fortran compiler driver to compile them. This
way:
  * the functionality of `f18` is reduced - it will only drive Flang (as
  opposed to delegating code-generation to an external tool on top of
  this)
  * we will able to switch between `f18` and `flang-new` for unparsing before
  an external Fortran compiler is called for code-generation

The updated `flang` bash script needs to specify the output file when
using the `-fdebug-unparse` action. Both `f18` and `flang-new` have been
updated accordingly.

These changes were discussed in [1] as a requirement for replacing `f18`
with `flang-new`.

[1] https://lists.llvm.org/pipermail/flang-dev/2021-April/000677.html

Differential Revision: https://reviews.llvm.org/D103177
2021-07-01 13:56:38 +01:00
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 2a7bb8494e [flang][driver] Add `-fno-analyzed-objects-for-unparse`
This patch adds a new option for the new Flang driver:
`-fno-analyzed-objects-for-unparse`. The semantics are similar to
`-funparse-typed-exprs-to-f18-fc` from `f18`. For consistency, the
latter is replaced with `-fno-analyzed-objects-for-unparse`.

The new option controls the behaviour of the unparser (i.e. the action
corresponding to `-fdebug-unparse`). The default behaviour is to use the
analyzed objects when unparsing. The new flag can be used to turn this
off, so that the original parse-tree objects are used. The analyzed
objects are generated during the semantic checks [1].

This patch also updates the semantics of
`-fno-analyzed-objects-for-unparse`/`-funparse-typed-exprs-to-f18-fc`
in `f18`, so that this flag is always taken into account when `Unparse`
is used (this way the semantics in `f18` and `flang-new` are identical).

The added test file is based on example from Peter Steinfeld.

[1]
https://github.com/llvm/llvm-project/blob/main/flang/docs/Semantics.md

Differential Revision: https://reviews.llvm.org/D103612
2021-06-25 13:28:12 +01:00
Andrzej Warzynski a6be6e31f1 [flang][driver] Add `-fdebug-dump-all`
The new option will run the semantic checks and then dump the parse tree
and all the symbols. This is equivalent to running the driver twice,
once with `-fdebug-dump-parse-tree` and then with
the `-fdebug-dump-symbols` action flag.

Currently we wouldn't be able to achieve the same by simply running:
```
flang-new -fc1 -fdebug-dump-parse-tree -fdebug-dump-symbols <input-file>
```
That's because the new driver will only run one frontend action per
invocation (both of the flags used here are action flags). Diverging
from this design would lead to costly compromises and it's best avoided.

We may want to consider re-designing our debugging actions (and action
options) in the future so that there's more code re-use. For now, I'm
focusing on making sure that we support all the major cases requested by
our users.

Differential Revision: https://reviews.llvm.org/D104305
2021-06-16 07:54:27 +00:00
Stuart Ellis e1da3297d2 [flang][driver] Add support for the "-init-only" option
Adding the `-init-only` option and corresponding frontend action to
generate a diagnostic.

`-init-only` vs `-test-io`:
`-init-only` ignores the input (it never calls the prescanner)
`-test-io` is similar to `-init-only`, but does read and print the input
without calling the prescanner.

This patch also adds a Driver test to check this action.

Reviewed By: awarzynski, AMDChirag

Differential Revision: https://reviews.llvm.org/D102849
2021-06-07 15:40:26 +01:00
Andrzej Warzynski 2b4c9bc4d4 [flang][driver] Add checks for missing option arguments
With this patch, the following invocation of the frontend driver will
return an error:
```
flang-new -fc1 input-file.f90 -o
```
Similar logic applies to other options that require arguments.

Similar checks are already available in the compiler driver, flang-new
(that's implemented in clangDriver).

Differential Revision: https://reviews.llvm.org/D103554
2021-06-04 15:16:56 +01:00
Andrzej Warzynski 20bd2142d4 [flang][driver] Add support for `-module-suffix`
This option is supported in `f18`, but not yet available in `flang-new`.
It is required in order to call `flang-new` from the `flang` bash
script.

Differential Revision: https://reviews.llvm.org/D103613
2021-06-04 13:58:04 +01:00