[FLANG] allow -fopenmp= (#86816)

This enables the -fopenmp=<library> option to the set of options supported by flang. The generated arguments for the FC1 compilation will appear in a slightly different order, so one test had to be updated to be less sensitive to order of the arguments.
llvm · Apr 5, 2024 · 6d2f57d · 6d2f57d
1 parent c6e38b9
commit 6d2f57d
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Showing 5 changed files with 114 additions and 24 deletions.
diff --git a/clang/include/clang/Basic/DiagnosticDriverKinds.td b/clang/include/clang/Basic/DiagnosticDriverKinds.td
@@ -142,6 +142,9 @@ def warn_drv_unsupported_diag_option_for_flang : Warning<
 def warn_drv_unsupported_option_for_processor : Warning<
   "ignoring '%0' option as it is not currently supported for processor '%1'">,
   InGroup<OptionIgnored>;
+def warn_drv_unsupported_openmp_library : Warning<
+  "The library '%0=%1' is not supported, openmp is not be enabled">,
+  InGroup<OptionIgnored>;
 
 def err_drv_invalid_thread_model_for_target : Error<
   "invalid thread model '%0' in '%1' for this target">;

diff --git a/clang/include/clang/Driver/Options.td b/clang/include/clang/Driver/Options.td
@@ -3425,7 +3425,8 @@ defm openmp_extensions: BoolFOption<"openmp-extensions",
           "Enable all Clang extensions for OpenMP directives and clauses">,
   NegFlag<SetFalse, [NoArgumentUnused], [ClangOption, CC1Option],
           "Disable all Clang extensions for OpenMP directives and clauses">>;
-def fopenmp_EQ : Joined<["-"], "fopenmp=">, Group<f_Group>;
+def fopenmp_EQ : Joined<["-"], "fopenmp=">, Group<f_Group>,
+  Visibility<[ClangOption, CC1Option, FlangOption, FC1Option]>;
 def fopenmp_use_tls : Flag<["-"], "fopenmp-use-tls">, Group<f_Group>,
   Flags<[NoArgumentUnused, HelpHidden]>;
 def fnoopenmp_use_tls : Flag<["-"], "fnoopenmp-use-tls">, Group<f_Group>,

diff --git a/clang/lib/Driver/ToolChains/Flang.cpp b/clang/lib/Driver/ToolChains/Flang.cpp
@@ -35,27 +35,18 @@ static void addDashXForInput(const ArgList &Args, const InputInfo &Input,
 
 void Flang::addFortranDialectOptions(const ArgList &Args,
                                      ArgStringList &CmdArgs) const {
-  Args.addAllArgs(CmdArgs, {options::OPT_ffixed_form,
-                            options::OPT_ffree_form,
-                            options::OPT_ffixed_line_length_EQ,
-                            options::OPT_fopenmp,
-                            options::OPT_fopenmp_version_EQ,
-                            options::OPT_fopenacc,
-                            options::OPT_finput_charset_EQ,
-                            options::OPT_fimplicit_none,
-                            options::OPT_fno_implicit_none,
-                            options::OPT_fbackslash,
-                            options::OPT_fno_backslash,
-                            options::OPT_flogical_abbreviations,
-                            options::OPT_fno_logical_abbreviations,
-                            options::OPT_fxor_operator,
-                            options::OPT_fno_xor_operator,
-                            options::OPT_falternative_parameter_statement,
-                            options::OPT_fdefault_real_8,
-                            options::OPT_fdefault_integer_8,
-                            options::OPT_fdefault_double_8,
-                            options::OPT_flarge_sizes,
-                            options::OPT_fno_automatic});
+  Args.addAllArgs(
+      CmdArgs, {options::OPT_ffixed_form, options::OPT_ffree_form,
+                options::OPT_ffixed_line_length_EQ, options::OPT_fopenacc,
+                options::OPT_finput_charset_EQ, options::OPT_fimplicit_none,
+                options::OPT_fno_implicit_none, options::OPT_fbackslash,
+                options::OPT_fno_backslash, options::OPT_flogical_abbreviations,
+                options::OPT_fno_logical_abbreviations,
+                options::OPT_fxor_operator, options::OPT_fno_xor_operator,
+                options::OPT_falternative_parameter_statement,
+                options::OPT_fdefault_real_8, options::OPT_fdefault_integer_8,
+                options::OPT_fdefault_double_8, options::OPT_flarge_sizes,
+                options::OPT_fno_automatic});
 }
 
 void Flang::addPreprocessingOptions(const ArgList &Args,
@@ -763,6 +754,35 @@ void Flang::ConstructJob(Compilation &C, const JobAction &JA,
   // Add other compile options
   addOtherOptions(Args, CmdArgs);
 
+  // Forward flags for OpenMP. We don't do this if the current action is an
+  // device offloading action other than OpenMP.
+  if (Args.hasFlag(options::OPT_fopenmp, options::OPT_fopenmp_EQ,
+                   options::OPT_fno_openmp, false) &&
+      (JA.isDeviceOffloading(Action::OFK_None) ||
+       JA.isDeviceOffloading(Action::OFK_OpenMP))) {
+    switch (D.getOpenMPRuntime(Args)) {
+    case Driver::OMPRT_OMP:
+    case Driver::OMPRT_IOMP5:
+      // Clang can generate useful OpenMP code for these two runtime libraries.
+      CmdArgs.push_back("-fopenmp");
+      Args.AddAllArgs(CmdArgs, options::OPT_fopenmp_version_EQ);
+
+      // FIXME: Clang supports a whole bunch more flags here.
+      break;
+    default:
+      // By default, if Clang doesn't know how to generate useful OpenMP code
+      // for a specific runtime library, we just don't pass the '-fopenmp' flag
+      // down to the actual compilation.
+      // FIXME: It would be better to have a mode which *only* omits IR
+      // generation based on the OpenMP support so that we get consistent
+      // semantic analysis, etc.
+      const Arg *A = Args.getLastArg(options::OPT_fopenmp_EQ);
+      D.Diag(diag::warn_drv_unsupported_openmp_library)
+          << A->getSpelling() << A->getValue();
+      break;
+    }
+  }
+
   // Offloading related options
   addOffloadOptions(C, Inputs, JA, Args, CmdArgs);
 

diff --git a/flang/test/Driver/fopenmp.f90 b/flang/test/Driver/fopenmp.f90
@@ -0,0 +1,61 @@
+! RUN: %flang -target x86_64-linux-gnu -fopenmp=libomp -c %s -### 2>&1 | FileCheck %s --check-prefix=CHECK-FC1-OPENMP
+! RUN: %flang -target x86_64-linux-gnu -fopenmp=libgomp -c %s -### 2>&1 | FileCheck %s --check-prefix=CHECK-FC1-NO-OPENMP
+! RUN: %flang -target x86_64-linux-gnu -fopenmp=libiomp5 -c %s -### 2>&1 | FileCheck %s --check-prefix=CHECK-FC1-OPENMP
+! RUN: %flang -target x86_64-apple-darwin -fopenmp=libomp -c %s -### 2>&1 | FileCheck %s --check-prefix=CHECK-FC1-OPENMP
+! RUN: %flang -target x86_64-apple-darwin -fopenmp=libgomp -c %s -### 2>&1 | FileCheck %s --check-prefix=CHECK-FC1-NO-OPENMP
+! RUN: %flang -target x86_64-apple-darwin -fopenmp=libiomp5 -c %s -### 2>&1 | FileCheck %s --check-prefix=CHECK-FC1-OPENMP
+! RUN: %flang -target x86_64-freebsd -fopenmp=libomp -c %s -### 2>&1 | FileCheck %s --check-prefix=CHECK-FC1-OPENMP
+! RUN: %flang -target x86_64-freebsd -fopenmp=libgomp -c %s -### 2>&1 | FileCheck %s --check-prefix=CHECK-FC1-NO-OPENMP
+! RUN: %flang -target x86_64-freebsd -fopenmp=libiomp5 -c %s -### 2>&1 | FileCheck %s --check-prefix=CHECK-FC1-OPENMP
+! RUN: %flang -target x86_64-windows-gnu -fopenmp=libomp -c %s -### 2>&1 | FileCheck %s --check-prefix=CHECK-FC1-OPENMP
+! RUN: %flang -target x86_64-windows-gnu -fopenmp=libgomp -c %s -### 2>&1 | FileCheck %s --check-prefix=CHECK-FC1-NO-OPENMP --check-prefix=CHECK-WARNING
+! RUN: %flang -target x86_64-windows-gnu -fopenmp=libiomp5 -c %s -### 2>&1 | FileCheck %s --check-prefix=CHECK-FC1-OPENMP
+
+! CHECK-FC1-OPENMP: "-fc1"
+! CHECK-FC1-OPENMP: "-fopenmp"
+!
+! CHECK-WARNING: warning: The library '-fopenmp=={{.*}}' is not supported, openmp is not be enabled
+! CHECK-FC1-NO-OPENMP: "-fc1"
+! CHECK-FC1-NO-OPENMP-NOT: "-fopenmp"
+!
+! RUN: %flang -target x86_64-linux-gnu -fopenmp=libomp %s -o %t -### 2>&1 | FileCheck %s --check-prefix=CHECK-LD-OMP
+! RUN: %flang -target x86_64-linux-gnu -fopenmp=libgomp %s -o %t -### 2>&1 | FileCheck %s --check-prefix=CHECK-LD-GOMP --check-prefix=CHECK-LD-GOMP-RT
+! RUN: %flang -target x86_64-linux-gnu -fopenmp=libiomp5 %s -o %t -### 2>&1 | FileCheck %s --check-prefix=CHECK-LD-IOMP5
+!
+! RUN: %flang -target x86_64-darwin -fopenmp=libomp %s -o %t -### 2>&1 | FileCheck %s --check-prefix=CHECK-LD-OMP
+! RUN: %flang -target x86_64-darwin -fopenmp=libgomp %s -o %t -### 2>&1 | FileCheck %s --check-prefix=CHECK-LD-GOMP --check-prefix=CHECK-LD-GOMP-NO-RT
+! RUN: %flang -target x86_64-darwin -fopenmp=libiomp5 %s -o %t -### 2>&1 | FileCheck %s --check-prefix=CHECK-LD-IOMP5
+!
+! RUN: %flang -target x86_64-freebsd -fopenmp=libomp %s -o %t -### 2>&1 | FileCheck %s --check-prefix=CHECK-LD-OMP
+! RUN: %flang -target x86_64-freebsd -fopenmp=libgomp %s -o %t -### 2>&1 | FileCheck %s --check-prefix=CHECK-LD-GOMP --check-prefix=CHECK-LD-GOMP-NO-RT
+! RUN: %flang -target x86_64-freebsd -fopenmp=libiomp5 %s -o %t -### 2>&1 | FileCheck %s --check-prefix=CHECK-LD-IOMP5
+!
+! RUN: %flang -target x86_64-windows-gnu -fopenmp=libomp %s -o %t -### 2>&1 | FileCheck %s --check-prefix=CHECK-LD-OMP
+! RUN: %flang -target x86_64-windows-gnu -fopenmp=libgomp %s -o %t -### 2>&1 | FileCheck %s --check-prefix=CHECK-LD-GOMP --check-prefix=CHECK-LD-GOMP-NO-RT
+! RUN: %flang -target x86_64-windows-gnu -fopenmp=libiomp5 %s -o %t -### 2>&1 | FileCheck %s --check-prefix=CHECK-LD-IOMP5MD
+!
+! CHECK-LD-OMP: "{{.*}}ld{{(.exe)?}}"
+! CHECK-LD-OMP: "-lomp"
+!
+! CHECK-LD-GOMP: "{{.*}}ld{{(.exe)?}}"
+! CHECK-LD-GOMP: "-lgomp"
+! CHECK-LD-GOMP-RT: "-lrt"
+! CHECK-LD-GOMP-NO-RT-NOT: "-lrt"
+!
+! CHECK-LD-IOMP5: "{{.*}}ld{{(.exe)?}}"
+! CHECK-LD-IOMP5: "-liomp5"
+!
+! CHECK-LD-IOMP5MD: "{{.*}}ld{{(.exe)?}}"
+! CHECK-LD-IOMP5MD: "-liomp5md"
+!
+! We'd like to check that the default is sane, but until we have the ability
+! to *always* semantically analyze OpenMP without always generating runtime
+! calls (in the event of an unsupported runtime), we don't have a good way to
+! test the CC1 invocation. Instead, just ensure we do eventually link *some*
+! OpenMP runtime.
+!
+! CHECK-LD-ANY: "{{.*}}ld{{(.exe)?}}"
+! CHECK-LD-ANY: "-l{{(omp|gomp|iomp5)}}"
+!
+! CHECK-LD-ANYMD: "{{.*}}ld{{(.exe)?}}"
+! CHECK-LD-ANYMD: "-l{{(omp|gomp|iomp5md)}}"
diff --git a/flang/test/Driver/omp-driver-offload.f90 b/flang/test/Driver/omp-driver-offload.f90
@@ -57,9 +57,14 @@
 ! RUN: --target=aarch64-unknown-linux-gnu \
 ! RUN:   | FileCheck %s --check-prefix=OPENMP-OFFLOAD-ARGS
 ! OPENMP-OFFLOAD-ARGS: "{{[^"]*}}flang-new" "-fc1" "-triple" "aarch64-unknown-linux-gnu" {{.*}} "-fopenmp" {{.*}}.f90"
-! OPENMP-OFFLOAD-ARGS-NEXT: "{{[^"]*}}flang-new" "-fc1" "-triple" "amdgcn-amd-amdhsa" {{.*}} "-fopenmp" {{.*}} "-fopenmp-host-ir-file-path" "{{.*}}.bc" "-fopenmp-is-target-device" {{.*}}.f90"
+! OPENMP-OFFLOAD-ARGS-NEXT: "{{[^"]*}}flang-new" "-fc1" "-triple" "amdgcn-amd-amdhsa"
+! OPENMP-OFFLOAD-ARGS-SAME:  "-fopenmp"
+! OPENMP-OFFLOAD-ARGS-SAME:  "-fopenmp-host-ir-file-path" "{{.*}}.bc" "-fopenmp-is-target-device"
+! OPENMP-OFFLOAD-ARGS-SAME:  {{.*}}.f90"
 ! OPENMP-OFFLOAD-ARGS: "{{[^"]*}}clang-offload-packager{{.*}}" {{.*}} "--image=file={{.*}}.bc,triple=amdgcn-amd-amdhsa,arch=gfx90a,kind=openmp"
-! OPENMP-OFFLOAD-ARGS-NEXT: "{{[^"]*}}flang-new" "-fc1" "-triple" "aarch64-unknown-linux-gnu" {{.*}} "-fopenmp" {{.*}} "-fembed-offload-object={{.*}}.out" {{.*}}.bc"
+! OPENMP-OFFLOAD-ARGS-NEXT: "{{[^"]*}}flang-new" "-fc1" "-triple" "aarch64-unknown-linux-gnu"
+! OPENMP-OFFLOAD-ARGS-SAME:  "-fopenmp"
+! OPENMP-OFFLOAD-ARGS-SAME:  "-fembed-offload-object={{.*}}.out" {{.*}}.bc"
 
 ! Test -fopenmp with offload for RTL Flag Options
 ! RUN: %flang -### %s -o %t 2>&1 \