[OpenMP][MLIR][Flang][bbc][Driver] Add fopenmp-version and generate corresponding MLIR attribute

[domada]

Summary

This patch adds flag -fopenmp-version to the Flang frontend and bbc tool. This flag is lowered to MLIR OpenMP flag attribute.

[domada]

Patch rebased

[domada]

Patch rebased + clang format

[awarzynski]

All in all LGTM, but I'm not sure whether Flang should be defaulting to OpenMP 5.0. AFAIK, that's not supported yet.

clang/lib/Driver/ToolChains/Flang.cpp

46

Is this clang-format? Looks like a big block of unrelated changes (not against it).

[domada]

Patch rebased because I applied remarks for parent revision.

[domada]

In D150354#4337148, @awarzynski wrote:

All in all LGTM, but I'm not sure whether Flang should be defaulting to OpenMP 5.0. AFAIK, that's not supported yet.

If you wish I can set to OpenMP 4.5. But then we need to have two separate flags in clang/include/clang/Driver/Options.td (one for clang and the second one for flang).

clang/lib/Driver/ToolChains/Flang.cpp

46

Yes, this is output of clang format.

[kiranchandramohan]

In D150354#4342146, @domada wrote:

In D150354#4337148, @awarzynski wrote:

All in all LGTM, but I'm not sure whether Flang should be defaulting to OpenMP 5.0. AFAIK, that's not supported yet.

If you wish I can set to OpenMP 4.5. But then we need to have two separate flags in clang/include/clang/Driver/Options.td (one for clang and the second one for flang).

We will not be able to match the OpenMP support in clang (stand support level) soon. Although we have made lot of progress, we are effectively around 1.1. To stay true to the meaning of this metadata, we will have to have separate flags. But, I guess, fclang-openmp-version might not be acceptable to Clang folks who are used to using -fopenmp-version. Can't this be achieved by the same flag? On a cursory look, i don't see anything that prevents using the same flag but with different defaults in the code that is handling the flag.

[domada]

Change the default version of OpenMP version flag to 1.1 for flang. Modify the flag description text. No changes for Clang code.

[domada]

In D150354#4348785, @kiranchandramohan wrote:

In D150354#4342146, @domada wrote:

In D150354#4337148, @awarzynski wrote:

All in all LGTM, but I'm not sure whether Flang should be defaulting to OpenMP 5.0. AFAIK, that's not supported yet.

If you wish I can set to OpenMP 4.5. But then we need to have two separate flags in clang/include/clang/Driver/Options.td (one for clang and the second one for flang).

We will not be able to match the OpenMP support in clang (stand support level) soon. Although we have made lot of progress, we are effectively around 1.1. To stay true to the meaning of this metadata, we will have to have separate flags. But, I guess, fclang-openmp-version might not be acceptable to Clang folks who are used to using -fopenmp-version. Can't this be achieved by the same flag? On a cursory look, i don't see anything that prevents using the same flag but with different defaults in the code that is handling the flag.

Hi Kiran, you were right. It is possible to set different value in code for the same flag. I updated the patch and I set the default value of OpenMP version to 1.1.

I updated only this patch and I did not change the previous patch: https://reviews.llvm.org/D150351 . Is it ok for you?

[kiranchandramohan]

LGTM.

Target-related constructs came in as part of OpenMP 4.0. Would you want to have a different default for the device version?

clang/include/clang/Driver/Options.td

 def fomit_frame_pointer : Flag<["-"], "fomit-frame-pointer">, Group<f_Group>,
   HelpText<"Omit the frame pointer from functions that don't need it. "
   "Some stack unwinding cases, such as profilers and sanitizers, may prefer specifying -fno-omit-frame-pointer. "
   "On many targets, -O1 and higher omit the frame pointer by default. "
   "-m[no-]omit-leaf-frame-pointer takes precedence for leaf functions">;
 def fopenmp : Flag<["-"], "fopenmp">, Group<f_Group>, Flags<[CC1Option, NoArgumentUnused, FlangOption, FC1Option]>,
   HelpText<"Parse OpenMP pragmas and generate parallel code.">;
 def fno_openmp : Flag<["-"], "fno-openmp">, Group<f_Group>, Flags<[NoArgumentUnused]>;
-def fopenmp_version_EQ : Joined<["-"], "fopenmp-version=">, Group<f_Group>, Flags<[CC1Option, NoArgumentUnused]>,
+def fopenmp_version_EQ : Joined<["-"], "fopenmp-version=">, Group<f_Group>, Flags<[CC1Option, NoArgumentUnused, FlangOption, FC1Option]>,
   HelpText<"Set OpenMP version (e.g. 45 for OpenMP 4.5, 50 for OpenMP 5.0). Default value is 50.">;
 defm openmp_extensions: BoolFOption<"openmp-extensions",
   LangOpts<"OpenMPExtensions">, DefaultTrue,
   PosFlag<SetTrue, [CC1Option, NoArgumentUnused],
           "Enable all Clang extensions for OpenMP directives and clauses">,
   NegFlag<SetFalse, [CC1Option, NoArgumentUnused],
           "Disable all Clang extensions for OpenMP directives and clauses">>;
 def fopenmp_EQ : Joined<["-"], "fopenmp=">, Group<f_Group>;

clang/lib/Driver/ToolChains/Flang.cpp

static void addDashXForInput(const ArgList &Args, const InputInfo &Input,
   // Map the driver type to the frontend type.
   CmdArgs.push_back(types::getTypeName(Input.getType()));
 }
 
 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_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});
 }
 
 void Flang::addPreprocessingOptions(const ArgList &Args,
                                     ArgStringList &CmdArgs) const {
   Args.AddAllArgs(CmdArgs,
                   {options::OPT_P, options::OPT_D, options::OPT_U,
                    options::OPT_I, options::OPT_cpp, options::OPT_nocpp});
 }
 

flang/include/flang/Frontend/LangOptions.def

 /// calculation
 LANGOPT(ApproxFunc, 1, false)
 /// Allow optimizations that ignore the sign of floating point zeros
 LANGOPT(NoSignedZeros, 1, false)
 /// Allow reassociation transformations for floating-point instructions
 LANGOPT(AssociativeMath, 1, false)
 /// Allow division operations to be reassociated
 LANGOPT(ReciprocalMath, 1, false)
+/// Specify version of OpenMP standard
+LANGOPT(OpenMPVersion, 32, 0)
 /// Generate code only for OpenMP target device
 LANGOPT(OpenMPIsDevice, 1, false)
 /// Enable debugging in the OpenMP offloading device RTL
 LANGOPT(OpenMPTargetDebug, 32, 0)
 /// Assume work-shared loops do not have more iterations than participating
 /// threads.
 LANGOPT(OpenMPThreadSubscription, 1, 0)
 /// Assume distributed loops do not have more iterations than participating

flang/include/flang/Tools/CrossToolHelpers.h

 
 #include "mlir/Dialect/OpenMP/OpenMPDialect.h"
 #include "mlir/IR/BuiltinOps.h"
 
 struct OffloadModuleOpts {
   OffloadModuleOpts() {}
   OffloadModuleOpts(uint32_t OpenMPTargetDebug, bool OpenMPTeamSubscription,
       bool OpenMPThreadSubscription, bool OpenMPNoThreadState,
-      bool OpenMPNoNestedParallelism, bool OpenMPIsDevice,
+      bool OpenMPNoNestedParallelism, bool OpenMPIsDevice, uint32_t OpenMPVersion,
       std::string OMPHostIRFile = {})
       : OpenMPTargetDebug(OpenMPTargetDebug),
         OpenMPTeamSubscription(OpenMPTeamSubscription),
         OpenMPThreadSubscription(OpenMPThreadSubscription),
         OpenMPNoThreadState(OpenMPNoThreadState),
         OpenMPNoNestedParallelism(OpenMPNoNestedParallelism),
-        OpenMPIsDevice(OpenMPIsDevice), OMPHostIRFile(OMPHostIRFile) {}
+        OpenMPIsDevice(OpenMPIsDevice), OpenMPVersion(OpenMPVersion), OMPHostIRFile(OMPHostIRFile) {}
 
   OffloadModuleOpts(Fortran::frontend::LangOptions &Opts)
       : OpenMPTargetDebug(Opts.OpenMPTargetDebug),
         OpenMPTeamSubscription(Opts.OpenMPTeamSubscription),
         OpenMPThreadSubscription(Opts.OpenMPThreadSubscription),
         OpenMPNoThreadState(Opts.OpenMPNoThreadState),
         OpenMPNoNestedParallelism(Opts.OpenMPNoNestedParallelism),
-        OpenMPIsDevice(Opts.OpenMPIsDevice), OMPHostIRFile(Opts.OMPHostIRFile) {
+        OpenMPIsDevice(Opts.OpenMPIsDevice),OpenMPVersion(Opts.OpenMPVersion),  OMPHostIRFile(Opts.OMPHostIRFile) {
   }
 
   uint32_t OpenMPTargetDebug = 0;
   bool OpenMPTeamSubscription = false;
   bool OpenMPThreadSubscription = false;
   bool OpenMPNoThreadState = false;
   bool OpenMPNoNestedParallelism = false;
   bool OpenMPIsDevice = false;
+  uint32_t OpenMPVersion = 50;
   std::string OMPHostIRFile = {};
 };
 
 //  Shares assinging of the OpenMP OffloadModuleInterface and its assorted
 //  attributes accross Flang tools (bbc/flang)
 void setOffloadModuleInterfaceAttributes(
     mlir::ModuleOp &module, OffloadModuleOpts Opts) {
   // Should be registered by the OpenMPDialect
   if (auto offloadMod = llvm::dyn_cast<mlir::omp::OffloadModuleInterface>(
           module.getOperation())) {
     offloadMod.setIsDevice(Opts.OpenMPIsDevice);
+    offloadMod.setVersion(Opts.OpenMPVersion);
     if (Opts.OpenMPIsDevice) {
       offloadMod.setFlags(Opts.OpenMPTargetDebug, Opts.OpenMPTeamSubscription,
           Opts.OpenMPThreadSubscription, Opts.OpenMPNoThreadState,
-          Opts.OpenMPNoNestedParallelism);
+          Opts.OpenMPNoNestedParallelism, Opts.OpenMPVersion);
 
       if (!Opts.OMPHostIRFile.empty())
         offloadMod.setHostIRFilePath(Opts.OMPHostIRFile);
     }
   }
 }
 
 //  Shares assinging of the OpenMP OffloadModuleInterface and its TargetCPU

flang/lib/Frontend/CompilerInvocation.cpp

if (args.hasArg(clang::driver::options::OPT_flarge_sizes))
     res.getDefaultKinds().set_sizeIntegerKind(8);
 
   // -fopenmp and -fopenacc
   if (args.hasArg(clang::driver::options::OPT_fopenacc)) {
     res.getFrontendOpts().features.Enable(
         Fortran::common::LanguageFeature::OpenACC);
   }
   if (args.hasArg(clang::driver::options::OPT_fopenmp)) {
+    //By default OpenMP is set to 5.0 version
+    res.getLangOpts().OpenMPVersion = 50;
     res.getFrontendOpts().features.Enable(
         Fortran::common::LanguageFeature::OpenMP);
-
+    if (int Version = getLastArgIntValue(
+            args, clang::driver::options::OPT_fopenmp_version_EQ,
+            res.getLangOpts().OpenMPVersion, diags)) {
+      res.getLangOpts().OpenMPVersion = Version;
+    }
     if (args.hasArg(clang::driver::options::OPT_fopenmp_is_device)) {
       res.getLangOpts().OpenMPIsDevice = 1;
 
       // Get OpenMP host file path if any and report if a non existent file is
       // found
       if (auto *arg = args.getLastArg(
               clang::driver::options::OPT_fopenmp_host_ir_file_path)) {
         res.getLangOpts().OMPHostIRFile = arg->getValue();

flang/test/Driver/driver-help-hidden.f90

 ! CHECK-NEXT: -fno-automatic         Implies the SAVE attribute for non-automatic local objects in subprograms unless RECURSIVE
 ! CHECK-NEXT: -fno-color-diagnostics  Disable colors in diagnostics
 ! CHECK-NEXT: -fno-integrated-as     Disable the integrated assembler
 ! CHECK-NEXT: -fno-signed-zeros      Allow optimizations that ignore the sign of floating point zeros
 ! CHECK-NEXT: -fno-stack-arrays      Allocate array temporaries on the heap (default)
 ! CHECK-NEXT: -fno-version-loops-for-stride
 ! CHECK-NEXT:                        Do not create unit-strided loops (default)
 ! CHECK-NEXT: -fopenacc              Enable OpenACC
+! CHECK-NEXT: -fopenmp-version=<value>
+! CHECK-NEXT:                        Set OpenMP version (e.g. 45 for OpenMP 4.5, 50 for OpenMP 5.0). Default value is 50.
 ! CHECK-NEXT: -fopenmp               Parse OpenMP pragmas and generate parallel code.
 ! CHECK-NEXT: -fpass-plugin=<dsopath> Load pass plugin from a dynamic shared object file (only with new pass manager).
 ! CHECK-NEXT: -freciprocal-math      Allow division operations to be reassociated
 ! CHECK-NEXT: -fstack-arrays         Attempt to allocate array temporaries on the stack, no matter their size
 ! CHECK-NEXT: -fsyntax-only          Run the preprocessor, parser and semantic analysis stages
 ! CHECK-NEXT: -funderscoring         Appends one trailing underscore to external names
 ! CHECK-NEXT: -fversion-loops-for-stride
 ! CHECK-NEXT:                        Create unit-strided versions of loops

flang/test/Driver/driver-help.f90

 ! HELP-NEXT: -fno-automatic         Implies the SAVE attribute for non-automatic local objects in subprograms unless RECURSIVE
 ! HELP-NEXT: -fno-color-diagnostics  Disable colors in diagnostics
 ! HELP-NEXT: -fno-integrated-as      Disable the integrated assembler
 ! HELP-NEXT: -fno-signed-zeros      Allow optimizations that ignore the sign of floating point zeros
 ! HELP-NEXT: -fno-stack-arrays      Allocate array temporaries on the heap (default)
 ! HELP-NEXT: -fno-version-loops-for-stride
 ! HELP-NEXT:                        Do not create unit-strided loops (default)
 ! HELP-NEXT: -fopenacc              Enable OpenACC
+! HELP-NEXT: -fopenmp-version=<value>
+! HELP-NEXT:                        Set OpenMP version (e.g. 45 for OpenMP 4.5, 50 for OpenMP 5.0). Default value is 50.
 ! HELP-NEXT: -fopenmp               Parse OpenMP pragmas and generate parallel code.
 ! HELP-NEXT: -fpass-plugin=<dsopath> Load pass plugin from a dynamic shared object file (only with new pass manager).
 ! HELP-NEXT: -freciprocal-math      Allow division operations to be reassociated
 ! HELP-NEXT: -fstack-arrays         Attempt to allocate array temporaries on the stack, no matter their size
 ! HELP-NEXT: -fsyntax-only          Run the preprocessor, parser and semantic analysis stages
 ! HELP-NEXT: -funderscoring         Appends one trailing underscore to external names
 ! HELP-NEXT: -fversion-loops-for-stride
 ! HELP-NEXT:                        Create unit-strided versions of loops

 ! HELP-FC1-NEXT: -fno-stack-arrays      Allocate array temporaries on the heap (default)
 ! HELP-FC1-NEXT: -fno-version-loops-for-stride
 ! HELP-FC1-NEXT:                        Do not create unit-strided loops (default)
 ! HELP-FC1-NEXT: -fopenacc              Enable OpenACC
 ! HELP-FC1-NEXT: -fopenmp-host-ir-file-path <value> 
 ! HELP-FC1-NEXT:                        Path to the IR file produced by the frontend for the host.
 ! HELP-FC1-NEXT: -fopenmp-is-device     Generate code only for an OpenMP target device.
 ! HELP-FC1-NEXT: -fopenmp-target-debug  Enable debugging in the OpenMP offloading device RTL
+! HELP-FC1-NEXT: -fopenmp-version=<value>
+! HELP-FC1-NEXT:                        Set OpenMP version (e.g. 45 for OpenMP 4.5, 50 for OpenMP 5.0). Default value is 50.
 ! HELP-FC1-NEXT: -fopenmp               Parse OpenMP pragmas and generate parallel code.
 ! HELP-FC1-NEXT: -fpass-plugin=<dsopath> Load pass plugin from a dynamic shared object file (only with new pass manager).
 ! HELP-FC1-NEXT: -freciprocal-math      Allow division operations to be reassociated
 ! HELP-FC1-NEXT: -fstack-arrays         Attempt to allocate array temporaries on the stack, no matter their size
 ! HELP-FC1-NEXT: -fsyntax-only          Run the preprocessor, parser and semantic analysis stages
 ! HELP-FC1-NEXT: -funderscoring         Appends one trailing underscore to external names
 ! HELP-FC1-NEXT: -fversion-loops-for-stride
 ! HELP-FC1-NEXT:                        Create unit-strided versions of loops

flang/test/Driver/omp-driver-offload.f90

 ! RUN: -fopenmp-target-debug -fopenmp-assume-threads-oversubscription \
 ! RUN: -fopenmp-assume-teams-oversubscription -fopenmp-assume-no-nested-parallelism \
 ! RUN: -fopenmp-assume-no-thread-state \
 ! RUN: | FileCheck %s --check-prefixes=CHECK-RTL-ALL
 ! CHECK-RTL-ALL: "{{[^"]*}}flang-new" "-fc1" {{.*}} "-fopenmp" {{.*}} "-fopenmp-is-device" "-fopenmp-target-debug" "-fopenmp-assume-teams-oversubscription"
 ! CHECK-RTL-ALL: "-fopenmp-assume-threads-oversubscription" "-fopenmp-assume-no-thread-state" "-fopenmp-assume-no-nested-parallelism"
 ! CHECK-RTL-ALL: {{.*}}.f90"
 
+! RUN: %flang -### %s -o %t 2>&1 \
+! RUN: -fopenmp -fopenmp-targets=amdgcn-amd-amdhsa \
+! RUN: -fopenmp-version=45 \
+! RUN: | FileCheck %s --check-prefixes=CHECK-OPENMP-VERSION
+! CHECK-OPENMP-VERSION: "{{[^"]*}}flang-new" "-fc1" {{.*}} "-fopenmp" "-fopenmp-version=45" {{.*}}.f90"
+
 ! Test diagnostic error when host IR file is non-existent 
 ! RUN: not %flang_fc1 %s -o %t 2>&1 -fopenmp -fopenmp-is-device \
 ! RUN: -fopenmp-host-ir-file-path non-existant-file.bc \
 ! RUN: | FileCheck %s --check-prefix=HOST-IR-MISSING
 ! HOST-IR-MISSING: error: provided host compiler IR file 'non-existant-file.bc' is required to generate code for OpenMP target regions but cannot be found

flang/test/Lower/OpenMP/rtl-flags.f90

 !RUN: %flang_fc1 -emit-fir -fopenmp -fopenmp-is-device %s -o - | FileCheck %s --check-prefix=DEFAULT-DEVICE-FIR
-!RUN: %flang_fc1 -emit-fir -fopenmp %s -o - | FileCheck %s --check-prefix=DEFAULT-HOST-FIR
+!RUN: %flang_fc1 -emit-fir -fopenmp -fopenmp-version=45 %s -o - | FileCheck %s --check-prefix=DEFAULT-HOST-FIR
+!RUN: %flang_fc1 -emit-fir -fopenmp -fopenmp-is-device -fopenmp-version=45  %s -o - | FileCheck %s --check-prefix=DEFAULT-DEVICE-FIR-VERSION
+!RUN: %flang_fc1 -emit-fir -fopenmp -fopenmp-version=45 %s -o - | FileCheck %s --check-prefix=DEFAULT-HOST-FIR-VERSION
 !RUN: %flang_fc1 -emit-fir -fopenmp -fopenmp-target-debug -fopenmp-is-device %s -o - | FileCheck %s --check-prefix=DBG-DEVICE-FIR
 !RUN: %flang_fc1 -emit-fir -fopenmp -fopenmp-target-debug=111 -fopenmp-is-device %s -o - | FileCheck %s --check-prefix=DBG-EQ-DEVICE-FIR
 !RUN: %flang_fc1 -emit-fir -fopenmp -fopenmp-assume-teams-oversubscription -fopenmp-is-device %s -o - | FileCheck %s --check-prefix=TEAMS-OSUB-DEVICE-FIR
 !RUN: %flang_fc1 -emit-fir -fopenmp -fopenmp-assume-threads-oversubscription -fopenmp-is-device %s -o - | FileCheck %s --check-prefix=THREAD-OSUB-DEVICE-FIR
 !RUN: %flang_fc1 -emit-fir -fopenmp -fopenmp-assume-no-thread-state -fopenmp-is-device %s -o - | FileCheck %s --check-prefix=THREAD-STATE-DEVICE-FIR
 !RUN: %flang_fc1 -emit-fir -fopenmp -fopenmp-assume-no-nested-parallelism -fopenmp-is-device %s -o - | FileCheck %s --check-prefix=NEST-PAR-DEVICE-FIR
 !RUN: %flang_fc1 -emit-fir -fopenmp -fopenmp-target-debug -fopenmp-assume-teams-oversubscription -fopenmp-assume-no-nested-parallelism -fopenmp-assume-threads-oversubscription -fopenmp-assume-no-thread-state -fopenmp-is-device %s -o - | FileCheck %s --check-prefix=ALL-DEVICE-FIR
 !RUN: bbc -emit-fir -fopenmp -fopenmp-is-device -o - %s | FileCheck %s --check-prefix=DEFAULT-DEVICE-FIR
+!RUN: bbc -emit-fir -fopenmp -fopenmp-is-device -fopenmp-version=45 -o - %s | FileCheck %s --check-prefix=DEFAULT-DEVICE-FIR-VERSION
 !RUN: bbc -emit-fir -fopenmp -o - %s | FileCheck %s --check-prefix=DEFAULT-HOST-FIR
+!RUN: bbc -emit-fir -fopenmp -fopenmp-version=45 -o - %s | FileCheck %s --check-prefix=DEFAULT-HOST-FIR-VERSION
 !RUN: bbc -emit-fir -fopenmp -fopenmp-target-debug=111 -fopenmp-is-device -o - %s | FileCheck %s --check-prefix=DBG-EQ-DEVICE-FIR
 !RUN: bbc -emit-fir -fopenmp -fopenmp-assume-teams-oversubscription -fopenmp-is-device -o - %s | FileCheck %s --check-prefix=TEAMS-OSUB-DEVICE-FIR
 !RUN: bbc -emit-fir -fopenmp -fopenmp-assume-threads-oversubscription -fopenmp-is-device -o - %s | FileCheck %s --check-prefix=THREAD-OSUB-DEVICE-FIR
 !RUN: bbc -emit-fir -fopenmp -fopenmp-assume-no-thread-state -fopenmp-is-device -o - %s | FileCheck %s --check-prefix=THREAD-STATE-DEVICE-FIR
 !RUN: bbc -emit-fir -fopenmp -fopenmp-assume-no-nested-parallelism -fopenmp-is-device -o - %s | FileCheck %s --check-prefix=NEST-PAR-DEVICE-FIR
 !RUN: bbc -emit-fir -fopenmp -fopenmp-target-debug=1 -fopenmp-assume-teams-oversubscription -fopenmp-assume-no-nested-parallelism -fopenmp-assume-threads-oversubscription -fopenmp-assume-no-thread-state -fopenmp-is-device -o - %s | FileCheck %s --check-prefix=ALL-DEVICE-FIR
 
 !DEFAULT-DEVICE-FIR: module attributes {{{.*}}, omp.flags = #omp.flags<>, omp.is_device = #omp.isdevice<is_device = true>{{.*}}}
-!DEFAULT-HOST-FIR: module attributes {{{.*}},  omp.is_device = #omp.isdevice<is_device = false>{{.*}}}
+!DEFAULT-DEVICE-FIR-VERSION: module attributes {{{.*}}, omp.flags = #omp.flags<openmp_device_version = 45>, omp.is_device = #omp.isdevice<is_device = true>, omp.version = #omp.version<version = 45>{{.*}}
+!DEFAULT-HOST-FIR: module attributes {{{.*}},  omp.is_device = #omp.isdevice<is_device = false>{{.*}}
+!DEFAULT-HOST-FIR-VERSION: module attributes {{{.*}},  omp.is_device = #omp.isdevice<is_device = false>, omp.version = #omp.version<version = 45>{{.*}}
 !DBG-DEVICE-FIR: module attributes {{{.*}}, omp.flags = #omp.flags<debug_kind = 1>{{.*}}}
 !DBG-EQ-DEVICE-FIR: module attributes {{{.*}}, omp.flags = #omp.flags<debug_kind = 111>{{.*}}}
 !TEAMS-OSUB-DEVICE-FIR: module attributes {{{.*}}, omp.flags = #omp.flags<assume_teams_oversubscription = true>{{.*}}}
 !THREAD-OSUB-DEVICE-FIR: module attributes {{{.*}}, omp.flags = #omp.flags<assume_threads_oversubscription = true>{{.*}}}
 !THREAD-STATE-DEVICE-FIR: module attributes {{{.*}}, omp.flags = #omp.flags<assume_no_thread_state = true>{{.*}}}
 !NEST-PAR-DEVICE-FIR: module attributes {{{.*}}, omp.flags = #omp.flags<assume_no_nested_parallelism = true>{{.*}}}
 !ALL-DEVICE-FIR: module attributes {{{.*}}, omp.flags = #omp.flags<debug_kind = 1, assume_teams_oversubscription = true, assume_threads_oversubscription = true, assume_no_thread_state = true, assume_no_nested_parallelism = true>{{.*}}}
 subroutine omp_subroutine()
 end subroutine omp_subroutine

flang/tools/bbc/bbc.cpp

 static llvm::cl::opt<bool>
     enableOpenMPDevice("fopenmp-is-device",
                        llvm::cl::desc("enable openmp device compilation"),
                        llvm::cl::init(false));
 
 // A simplified subset of the OpenMP RTL Flags from Flang, only the primary
 // positive options are available, no negative options e.g. fopen_assume* vs
 // fno_open_assume*
+static llvm::cl::opt<uint32_t> setOpenMPVersion(
+    "fopenmp-version",
+    llvm::cl::desc("OpenMP standard version"),
+    llvm::cl::init(50));
+
 static llvm::cl::opt<uint32_t> setOpenMPTargetDebug(
     "fopenmp-target-debug",
     llvm::cl::desc("Enable debugging in the OpenMP offloading device RTL"),
     llvm::cl::init(0));
 
 static llvm::cl::opt<bool> setOpenMPThreadSubscription(
     "fopenmp-assume-threads-oversubscription",
     llvm::cl::desc("Assume work-shared loops do not have more "
auto burnside = Fortran::lower::LoweringBridge::create(
       semanticsContext.targetCharacteristics(), parsing.allCooked(), "",
       kindMap, loweringOptions, {});
   burnside.lower(parseTree, semanticsContext);
   mlir::ModuleOp mlirModule = burnside.getModule();
   if (enableOpenMP) {
     auto offloadModuleOpts =
         OffloadModuleOpts(setOpenMPTargetDebug, setOpenMPTeamSubscription,
                           setOpenMPThreadSubscription, setOpenMPNoThreadState,
-                          setOpenMPNoNestedParallelism, enableOpenMPDevice);
+                          setOpenMPNoNestedParallelism, enableOpenMPDevice, setOpenMPVersion);
     setOffloadModuleInterfaceAttributes(mlirModule, offloadModuleOpts);
   }
   std::error_code ec;
   std::string outputName = outputFilename;
   if (!outputName.size())
     outputName = llvm::sys::path::stem(inputFilename).str().append(".mlir");
   llvm::raw_fd_ostream out(outputName, ec);
   if (ec)

mlir/include/mlir/Dialect/OpenMP/OpenMPOps.td

 
 def FlagsAttr : OpenMP_Attr<"Flags", "flags"> {
   let parameters = (ins
     DefaultValuedParameter<"uint32_t", "0">:$debug_kind,
     DefaultValuedParameter<"bool", "false">:$assume_teams_oversubscription,
     DefaultValuedParameter<"bool", "false">:$assume_threads_oversubscription,
     DefaultValuedParameter<"bool", "false">:$assume_no_thread_state,
     DefaultValuedParameter<"bool", "false">:$assume_no_nested_parallelism,
-    DefaultValuedParameter<"uint32_t", "45">:$openmp_device_version
+    DefaultValuedParameter<"uint32_t", "50">:$openmp_device_version
   );
 
   let assemblyFormat = "`<` struct(params) `>`";
 }
 
 def TargetAttr : OpenMP_Attr<"Target", "target"> {
   let parameters = (ins
     StringRefParameter<>:$target_cpu,