[flang][driver] rename flang-new to flang (#110023)

This does a global rename from `flang-new` to `flang`. I also
removed/changed any TODOs that I found related to making this change.

---------

Co-authored-by: H. Vetinari <h.vetinari@gmx.com>
Co-authored-by: Andrzej Warzynski <andrzej.warzynski@arm.com>

.github/workflows/release-binaries.yml

@@ -328,7 +328,7 @@ jobs:
       run: |
         # Build some of the mlir tools that take a long time to link
         if [ "${{ needs.prepare.outputs.build-flang }}" = "true" ]; then
-          ninja -C ${{ steps.setup-stage.outputs.build-prefix }}/build/tools/clang/stage2-bins/ -j2 flang-new bbc
+          ninja -C ${{ steps.setup-stage.outputs.build-prefix }}/build/tools/clang/stage2-bins/ -j2 flang bbc
         fi
         ninja -C ${{ steps.setup-stage.outputs.build-prefix }}/build/tools/clang/stage2-bins/ \
             mlir-bytecode-parser-fuzzer \

clang/include/clang/Basic/DiagnosticDriverKinds.td

@@ -147,6 +147,9 @@ def warn_drv_unsupported_option_for_processor : Warning<
 def warn_drv_unsupported_openmp_library : Warning<
   "the library '%0=%1' is not supported, OpenMP will not be enabled">,
   InGroup<OptionIgnored>;
+def warn_openmp_experimental : Warning<
+  "OpenMP support in flang is still experimental">,
+  InGroup<ExperimentalOption>;
 
 def err_drv_invalid_thread_model_for_target : Error<
   "invalid thread model '%0' in '%1' for this target">;

clang/include/clang/Basic/DiagnosticGroups.td

@@ -1583,3 +1583,7 @@ def ExtractAPIMisuse : DiagGroup<"extractapi-misuse">;
 // Warnings about using the non-standard extension having an explicit specialization
 // with a storage class specifier.
 def ExplicitSpecializationStorageClass : DiagGroup<"explicit-specialization-storage-class">;
+
+// A warning for options that enable a feature that is not yet complete
+def ExperimentalOption : DiagGroup<"experimental-option">;
+

clang/include/clang/Driver/Options.td

@@ -6077,7 +6077,7 @@ def _sysroot_EQ : Joined<["--"], "sysroot=">, Visibility<[ClangOption, FlangOpti
 def _sysroot : Separate<["--"], "sysroot">, Alias<_sysroot_EQ>;
 
 //===----------------------------------------------------------------------===//
-// pie/pic options (clang + flang-new)
+// pie/pic options (clang + flang)
 //===----------------------------------------------------------------------===//
 let Visibility = [ClangOption, FlangOption] in {
 
@@ -6093,7 +6093,7 @@ def fno_pie : Flag<["-"], "fno-pie">, Group<f_Group>;
 } // let Vis = [Default, FlangOption]
 
 //===----------------------------------------------------------------------===//
-// Target Options (clang + flang-new)
+// Target Options (clang + flang)
 //===----------------------------------------------------------------------===//
 let Flags = [TargetSpecific] in {
 let Visibility = [ClangOption, FlangOption] in {

clang/lib/Driver/Driver.cpp

@@ -2029,7 +2029,7 @@ void Driver::PrintHelp(bool ShowHidden) const {
 
 void Driver::PrintVersion(const Compilation &C, raw_ostream &OS) const {
   if (IsFlangMode()) {
-    OS << getClangToolFullVersion("flang-new") << '\n';
+    OS << getClangToolFullVersion("flang") << '\n';
   } else {
     // FIXME: The following handlers should use a callback mechanism, we don't
     // know what the client would like to do.

clang/lib/Driver/ToolChain.cpp

@@ -386,6 +386,9 @@ static const DriverSuffix *FindDriverSuffix(StringRef ProgName, size_t &Pos) {
       {"cl", "--driver-mode=cl"},
       {"++", "--driver-mode=g++"},
       {"flang", "--driver-mode=flang"},
+      // For backwards compatibility, we create a symlink for `flang` called
+      // `flang-new`. This will be removed in the future.
+      {"flang-new", "--driver-mode=flang"},
       {"clang-dxc", "--driver-mode=dxc"},
   };
 

clang/lib/Driver/ToolChains/Flang.cpp

@@ -787,6 +787,9 @@ void Flang::ConstructJob(Compilation &C, const JobAction &JA,
 
       if (Args.hasArg(options::OPT_fopenmp_force_usm))
         CmdArgs.push_back("-fopenmp-force-usm");
+      // TODO: OpenMP support isn't "done" yet, so for now we warn that it
+      // is experimental.
+      D.Diag(diag::warn_openmp_experimental);
 
       // FIXME: Clang supports a whole bunch more flags here.
       break;
@@ -881,14 +884,12 @@ void Flang::ConstructJob(Compilation &C, const JobAction &JA,
 
   CmdArgs.push_back(Input.getFilename());
 
-  // TODO: Replace flang-new with flang once the new driver replaces the
-  // throwaway driver
-  const char *Exec = Args.MakeArgString(D.GetProgramPath("flang-new", TC));
+  const char *Exec = Args.MakeArgString(D.GetProgramPath("flang", TC));
   C.addCommand(std::make_unique<Command>(JA, *this,
                                          ResponseFileSupport::AtFileUTF8(),
                                          Exec, CmdArgs, Inputs, Output));
 }
 
-Flang::Flang(const ToolChain &TC) : Tool("flang-new", "flang frontend", TC) {}
+Flang::Flang(const ToolChain &TC) : Tool("flang", "flang frontend", TC) {}
 
 Flang::~Flang() {}

clang/test/Driver/flang/flang.f90

@@ -13,7 +13,7 @@
 ! * (no type specified, resulting in an object file)
 
 ! All invocations should begin with flang -fc1, consume up to here.
-! ALL-LABEL: "{{[^"]*}}flang-new{{[^"/]*}}" "-fc1"
+! ALL-LABEL: "{{[^"]*}}flang{{[^"/]*}}" "-fc1"
 
 ! Check that f90 files are not treated as "previously preprocessed"
 ! ... in --driver-mode=flang.

clang/test/Driver/flang/flang_ucase.F90

@@ -13,7 +13,7 @@
 ! * (no type specified, resulting in an object file)
 
 ! All invocations should begin with flang -fc1, consume up to here.
-! ALL-LABEL: "{{[^"]*}}flang-new{{[^"/]*}}" "-fc1"
+! ALL-LABEL: "{{[^"]*}}flang{{[^"/]*}}" "-fc1"
 
 ! Check that f90 files are not treated as "previously preprocessed"
 ! ... in --driver-mode=flang.

clang/test/Driver/flang/multiple-inputs-mixed.f90

@@ -1,7 +1,7 @@
 ! Check that flang can handle mixed C and fortran inputs.
 
 ! RUN: %clang --driver-mode=flang -### -fsyntax-only %S/Inputs/one.f90 %S/Inputs/other.c 2>&1 | FileCheck --check-prefixes=CHECK-SYNTAX-ONLY %s
-! CHECK-SYNTAX-ONLY-LABEL: "{{[^"]*}}flang-new{{[^"/]*}}" "-fc1"
+! CHECK-SYNTAX-ONLY-LABEL: "{{[^"]*}}flang{{[^"/]*}}" "-fc1"
 ! CHECK-SYNTAX-ONLY: "{{[^"]*}}/Inputs/one.f90"
 ! CHECK-SYNTAX-ONLY-LABEL: "{{[^"]*}}clang{{[^"/]*}}" "-cc1"
 ! CHECK-SYNTAX-ONLY: "{{[^"]*}}/Inputs/other.c"

clang/test/Driver/flang/multiple-inputs.f90

@@ -1,7 +1,7 @@
 ! Check that flang driver can handle multiple inputs at once.
 
 ! RUN: %clang --driver-mode=flang -### -fsyntax-only %S/Inputs/one.f90 %S/Inputs/two.f90 2>&1 | FileCheck --check-prefixes=CHECK-SYNTAX-ONLY %s
-! CHECK-SYNTAX-ONLY-LABEL: "{{[^"]*}}flang-new{{[^"/]*}}" "-fc1"
+! CHECK-SYNTAX-ONLY-LABEL: "{{[^"]*}}flang{{[^"/]*}}" "-fc1"
 ! CHECK-SYNTAX-ONLY: "{{[^"]*}}/Inputs/one.f90"
-! CHECK-SYNTAX-ONLY-LABEL: "{{[^"]*}}flang-new{{[^"/]*}}" "-fc1"
+! CHECK-SYNTAX-ONLY-LABEL: "{{[^"]*}}flang{{[^"/]*}}" "-fc1"
 ! CHECK-SYNTAX-ONLY: "{{[^"]*}}/Inputs/two.f90"

flang/docs/FlangDriver.md

@@ -15,17 +15,13 @@ local:
 ```
 
 There are two main drivers in Flang:
-* the compiler driver, `flang-new`
-* the frontend driver, `flang-new -fc1`
-
-> **_NOTE:_** The diagrams in this document refer to `flang` as opposed to
-> `flang-new`. Eventually, `flang-new` will be renamed as `flang` and the
-> diagrams reflect the final design that we are still working towards.
+* the compiler driver, `flang`
+* the frontend driver, `flang -fc1`
 
 The **compiler driver** will allow you to control all compilation phases (e.g.
 preprocessing, semantic checks, code-generation, code-optimisation, lowering
 and linking). For frontend specific tasks, the compiler driver creates a
-Fortran compilation job and delegates it to `flang-new -fc1`, the frontend
+Fortran compilation job and delegates it to `flang -fc1`, the frontend
 driver. For linking, it creates a linker job and calls an external linker (e.g.
 LLVM's [`lld`](https://lld.llvm.org/)). It can also call other tools such as
 external assemblers (e.g. [`as`](https://www.gnu.org/software/binutils/)). In
@@ -47,7 +43,7 @@ frontend. It uses MLIR and LLVM for code-generation and can be viewed as a
 driver for Flang, LLVM and MLIR libraries. Contrary to the compiler driver, it
 is not capable of calling any external tools (including linkers).  It is aware
 of all the frontend internals that are "hidden" from the compiler driver. It
-accepts many frontend-specific options not available in `flang-new` and as such
+accepts many frontend-specific options not available in `flang` and as such
 it provides a finer control over the frontend. Note that this tool is mostly
 intended for Flang developers. In particular, there are no guarantees about the
 stability of its interface and compiler developers can use it to experiment
@@ -62,30 +58,30 @@ frontend specific flag from the _compiler_ directly to the _frontend_ driver,
 e.g.:
 
 ```bash
-flang-new -Xflang -fdebug-dump-parse-tree input.f95
+flang -Xflang -fdebug-dump-parse-tree input.f95
 ```
 
-In the invocation above, `-fdebug-dump-parse-tree` is forwarded to `flang-new
+In the invocation above, `-fdebug-dump-parse-tree` is forwarded to `flang
 -fc1`. Without the forwarding flag, `-Xflang`, you would see the following
 warning:
 
 ```bash
-flang-new: warning: argument unused during compilation:
+flang: warning: argument unused during compilation:
 ```
 
-As `-fdebug-dump-parse-tree` is only supported by `flang-new -fc1`, `flang-new`
+As `-fdebug-dump-parse-tree` is only supported by `flang -fc1`, `flang`
 will ignore it when used without `Xflang`.
 
 ## Why Do We Need Two Drivers?
-As hinted above, `flang-new` and `flang-new -fc1` are two separate tools. The
-fact that these tools are accessed through one binary, `flang-new`, is just an
+As hinted above, `flang` and `flang -fc1` are two separate tools. The
+fact that these tools are accessed through one binary, `flang`, is just an
 implementation detail. Each tool has a separate list of options, albeit defined
 in the same file: `clang/include/clang/Driver/Options.td`.
 
 The separation helps us split various tasks and allows us to implement more
-specialised tools. In particular, `flang-new` is not aware of various
+specialised tools. In particular, `flang` is not aware of various
 compilation phases within the frontend (e.g. scanning, parsing or semantic
-checks). It does not have to be. Conversely, the frontend driver, `flang-new
+checks). It does not have to be. Conversely, the frontend driver, `flang
 -fc1`, needs not to be concerned with linkers or other external tools like
 assemblers. Nor does it need to know where to look for various systems
 libraries, which is usually OS and platform specific.
@@ -104,7 +100,7 @@ GCC](https://en.wikibooks.org/wiki/GNU_C_Compiler_Internals/GNU_C_Compiler_Archi
 In fact, Flang needs to adhere to this model in order to be able to re-use
 Clang's driver library. If you are more familiar with the [architecture of
 GFortran](https://gcc.gnu.org/onlinedocs/gcc-4.7.4/gfortran/About-GNU-Fortran.html)
-than Clang, then `flang-new` corresponds to `gfortran` and `flang-new -fc1` to
+than Clang, then `flang` corresponds to `gfortran` and `flang -fc1` to
 `f951`.
 
 ## Compiler Driver
@@ -135,15 +131,15 @@ output from one action is the input for the subsequent one. You can use the
 `-ccc-print-phases` flag to see the sequence of actions that the driver will
 create for your compiler invocation:
 ```bash
-flang-new -ccc-print-phases -E file.f
+flang -ccc-print-phases -E file.f
 +- 0: input, "file.f", f95-cpp-input
 1: preprocessor, {0}, f95
 ```
 As you can see, for `-E` the driver creates only two jobs and stops immediately
 after preprocessing. The first job simply prepares the input. For `-c`, the
 pipeline of the created jobs is more complex:
 ```bash
-flang-new -ccc-print-phases -c file.f
+flang -ccc-print-phases -c file.f
          +- 0: input, "file.f", f95-cpp-input
       +- 1: preprocessor, {0}, f95
    +- 2: compiler, {1}, ir
@@ -158,7 +154,7 @@ command to call the frontend driver is generated (more specifically, an
 instance of `clang::driver::Command`). Every command is bound to an instance of
 `clang::driver::Tool`. For Flang we introduced a specialisation of this class:
 `clang::driver::Flang`. This class implements the logic to either translate or
-forward compiler options to the frontend driver, `flang-new -fc1`.
+forward compiler options to the frontend driver, `flang -fc1`.
 
 You can read more on the design of `clangDriver` in Clang's [Driver Design &
 Internals](https://clang.llvm.org/docs/DriverInternals.html).
@@ -232,12 +228,12 @@ driver, `clang -cc1` and consists of the following classes:
 This list is not exhaustive and only covers the main classes that implement the
 driver. The main entry point for the frontend driver, `fc1_main`, is
 implemented in `flang/tools/flang-driver/driver.cpp`. It can be accessed by
-invoking the compiler driver, `flang-new`, with the `-fc1` flag.
+invoking the compiler driver, `flang`, with the `-fc1` flag.
 
 The frontend driver will only run one action at a time. If you specify multiple
 action flags, only the last one will be taken into account. The default action
 is `ParseSyntaxOnlyAction`, which corresponds to `-fsyntax-only`. In other
-words, `flang-new -fc1 <input-file>` is equivalent to `flang-new -fc1 -fsyntax-only
+words, `flang -fc1 <input-file>` is equivalent to `flang -fc1 -fsyntax-only
 <input-file>`.
 
 ## Adding new Compiler Options
@@ -262,8 +258,8 @@ similar semantics to your new option and start by copying that.
 For every new option, you will also have to define the visibility of the new
 option. This is controlled through the `Visibility` field. You can use the
 following Flang specific visibility flags to control this:
-  * `FlangOption` - this option will be available in the `flang-new` compiler driver,
-  * `FC1Option` - this option will be available in the `flang-new -fc1` frontend driver,
+  * `FlangOption` - this option will be available in the `flang` compiler driver,
+  * `FC1Option` - this option will be available in the `flang -fc1` frontend driver,
 
 Options that are supported by clang should explicitly specify `ClangOption` in
 `Visibility`, and options that are only supported in Flang should not specify
@@ -290,10 +286,10 @@ The parsing will depend on the semantics encoded in the TableGen definition.
 
 When adding a compiler driver option (i.e. an option that contains
 `FlangOption` among in it's `Visibility`) that you also intend to be understood
-by the frontend, make sure that it is either forwarded to `flang-new -fc1` or
+by the frontend, make sure that it is either forwarded to `flang -fc1` or
 translated into some other option that is accepted by the frontend driver. In
 the case of options that contain both `FlangOption` and `FC1Option` among its
-flags, we usually just forward from `flang-new` to `flang-new -fc1`. This is
+flags, we usually just forward from `flang` to `flang -fc1`. This is
 then tested in `flang/test/Driver/frontend-forward.F90`.
 
 What follows is usually very dependant on the meaning of the corresponding
@@ -339,11 +335,11 @@ just added using your new frontend option.
 
 ## CMake Support
 As of [#7246](https://gitlab.kitware.com/cmake/cmake/-/merge_requests/7246)
-(and soon to be released CMake 3.24.0), `cmake` can detect `flang-new` as a
+(CMake 3.28.0), `cmake` can detect `flang` as a
 supported Fortran compiler. You can configure your CMake projects to use
-`flang-new` as follows:
+`flang` as follows:
 ```bash
-cmake -DCMAKE_Fortran_COMPILER=<path/to/flang-new> <src/dir>
+cmake -DCMAKE_Fortran_COMPILER=<path/to/flang> <src/dir>
 ```
 You should see the following in the output:
 ```
@@ -353,14 +349,14 @@ where `<version>` corresponds to the LLVM Flang version.
 
 ## Testing
 In LIT, we define two variables that you can use to invoke Flang's drivers:
-* `%flang` is expanded as `flang-new` (i.e. the compiler driver)
-* `%flang_fc1` is expanded as `flang-new -fc1` (i.e. the frontend driver)
+* `%flang` is expanded as `flang` (i.e. the compiler driver)
+* `%flang_fc1` is expanded as `flang -fc1` (i.e. the frontend driver)
 
 For most regression tests for the frontend, you will want to use `%flang_fc1`.
 In some cases, the observable behaviour will be identical regardless of whether
 `%flang` or `%flang_fc1` is used. However, when you are using `%flang` instead
 of `%flang_fc1`, the compiler driver will add extra flags to the frontend
-driver invocation (i.e. `flang-new -fc1 -<extra-flags>`). In some cases that might
+driver invocation (i.e. `flang -fc1 -<extra-flags>`). In some cases that might
 be exactly what you want to test.  In fact, you can check these additional
 flags by using the `-###` compiler driver command line option.
 
@@ -380,7 +376,7 @@ plugins. The process for using plugins includes:
 * [Creating a plugin](#creating-a-plugin)
 * [Loading and running a plugin](#loading-and-running-a-plugin)
 
-Flang plugins are limited to `flang-new -fc1` and are currently only available /
+Flang plugins are limited to `flang -fc1` and are currently only available /
 been tested on Linux.
 
 ### Creating a Plugin
@@ -465,14 +461,14 @@ static FrontendPluginRegistry::Add<PrintFunctionNamesAction> X(
 
 ### Loading and Running a Plugin
 In order to use plugins, there are 2 command line options made available to the
-frontend driver, `flang-new -fc1`:
+frontend driver, `flang -fc1`:
 * [`-load <dsopath>`](#the--load-dsopath-option) for loading the dynamic shared
   object of the plugin
 * [`-plugin <name>`](#the--plugin-name-option) for calling the registered plugin
 
 Invocation of the example plugin is done through:
 ```bash
-flang-new -fc1 -load flangPrintFunctionNames.so -plugin print-fns file.f90
+flang -fc1 -load flangPrintFunctionNames.so -plugin print-fns file.f90
 ```
 
 Both these options are parsed in `flang/lib/Frontend/CompilerInvocation.cpp` and
@@ -493,7 +489,7 @@ reports an error diagnostic and returns `nullptr`.
 
 ### Enabling In-Tree Plugins
 For in-tree plugins, there is the CMake flag `FLANG_PLUGIN_SUPPORT`, enabled by
-default, that controls the exporting of executable symbols from `flang-new`,
+default, that controls the exporting of executable symbols from `flang`,
 which plugins need access to. Additionally, there is the CMake flag
 `LLVM_BUILD_EXAMPLES`, turned off by default, that is used to control if the
 example programs are built. This includes plugins that are in the
@@ -526,7 +522,7 @@ invocations `invokeFIROptEarlyEPCallbacks`, `invokeFIRInlinerCallback`, and
 `invokeFIROptLastEPCallbacks` for Flang drivers to be able to insert additonal
 passes at different points of the default pass pipeline. An example use of these
 extension point callbacks is shown in `registerDefaultInlinerPass` to invoke the
-default inliner pass in `flang-new`.
+default inliner pass in `flang`.
 
 ## LLVM Pass Plugins
 
@@ -539,15 +535,15 @@ documentation for
 [`llvm::PassBuilder`](https://llvm.org/doxygen/classllvm_1_1PassBuilder.html)
 for details.
 
-The framework to enable pass plugins in `flang-new` uses the exact same
+The framework to enable pass plugins in `flang` uses the exact same
 machinery as that used by `clang` and thus has the same capabilities and
 limitations.
 
 In order to use a pass plugin, the pass(es) must be compiled into a dynamic
 shared object which is then loaded using the `-fpass-plugin` option.
 
 ```
-flang-new -fpass-plugin=/path/to/plugin.so <file.f90>
+flang -fpass-plugin=/path/to/plugin.so <file.f90>
 ```
 
 This option is available in both the compiler driver and the frontend driver.
@@ -559,7 +555,7 @@ Pass extensions are similar to plugins, except that they can also be linked
 statically. Setting `-DLLVM_${NAME}_LINK_INTO_TOOLS` to `ON` in the cmake
 command turns the project into a statically linked extension. An example would
 be Polly, e.g., using `-DLLVM_POLLY_LINK_INTO_TOOLS=ON` would link Polly passes
-into `flang-new` as built-in middle-end passes.
+into `flang` as built-in middle-end passes.
 
 See the
 [`WritingAnLLVMNewPMPass`](https://llvm.org/docs/WritingAnLLVMNewPMPass.html#id9)

flang/docs/ImplementingASemanticCheck.md

@@ -68,7 +68,7 @@ of the call to `intentOutFunc()`:
 
 I also used this program to produce a parse tree for the program using the command:
 ```bash
-  flang-new -fc1 -fdebug-dump-parse-tree testfun.f90
+  flang -fc1 -fdebug-dump-parse-tree testfun.f90
 ```
 
 Here's the relevant fragment of the parse tree produced by the compiler:
@@ -296,7 +296,7 @@ In `lib/Semantics/check-do.cpp`, I added an (almost empty) implementation:
 I then built the compiler with these changes and ran it on my test program.
 This time, I made sure to invoke semantic checking.  Here's the command I used:
 ```bash
-  flang-new -fc1 -fdebug-unparse-with-symbols testfun.f90
+  flang -fc1 -fdebug-unparse-with-symbols testfun.f90
 ```
 
 This produced the output: