From 9b2fd1a6ec935b2e31bb2b6fda82b7377b9bbf79 Mon Sep 17 00:00:00 2001
From: Tom Eccles <tom.eccles@arm.com>
Date: Wed, 2 Apr 2025 10:43:48 +0100
Subject: [PATCH] [flang][OpenMP] Bump default OpenMP version to 3.1 (#133745)

Precise OpenMP standards support information is being documented in
#132707

Flang now has good support for OpenMP Version 3.1 and earlier.
---
 clang/include/clang/Driver/Options.td            |  2 +-
 flang/include/flang/Support/LangOptions.def      |  2 +-
 flang/include/flang/Tools/CrossToolHelpers.h     |  2 +-
 flang/lib/Frontend/CompilerInvocation.cpp        |  4 ++--
 flang/test/Driver/bbc-openmp-version-macro.f90   |  2 +-
 flang/test/Driver/flang-openmp-version-macro.f90 |  2 +-
 flang/test/Lower/OpenMP/rtl-flags.f90            | 16 ++++++++--------
 flang/tools/bbc/bbc.cpp                          |  2 +-
 8 files changed, 16 insertions(+), 16 deletions(-)

diff --git a/clang/include/clang/Driver/Options.td b/clang/include/clang/Driver/Options.td
index 4c0108807681..534631e43d26 100644
--- a/clang/include/clang/Driver/Options.td
+++ b/clang/include/clang/Driver/Options.td
@@ -3591,7 +3591,7 @@ def fopenmp_version_EQ : Joined<["-"], "fopenmp-version=">, Group<f_Group>,
   Flags<[NoArgumentUnused]>,
   Visibility<[ClangOption, CC1Option, FlangOption, FC1Option]>,
   HelpText<OpenMPVersionHelp<"Clang", "51">.str>,
-  HelpTextForVariants<[FlangOption, FC1Option], OpenMPVersionHelp<"Flang", "11">.str>;
+  HelpTextForVariants<[FlangOption, FC1Option], OpenMPVersionHelp<"Flang", "31">.str>;
 defm openmp_extensions: BoolFOption<"openmp-extensions",
   LangOpts<"OpenMPExtensions">, DefaultTrue,
   PosFlag<SetTrue, [NoArgumentUnused], [ClangOption, CC1Option],
diff --git a/flang/include/flang/Support/LangOptions.def b/flang/include/flang/Support/LangOptions.def
index 1bfdba9cc2c1..d5bf7a2ecc03 100644
--- a/flang/include/flang/Support/LangOptions.def
+++ b/flang/include/flang/Support/LangOptions.def
@@ -39,7 +39,7 @@ LANGOPT(AssociativeMath, 1, false)
 /// Allow division operations to be reassociated
 LANGOPT(ReciprocalMath, 1, false)
 /// Specify version of OpenMP standard
-LANGOPT(OpenMPVersion, 32, 0)
+LANGOPT(OpenMPVersion, 31, 0)
 /// Generate code only for OpenMP target device
 LANGOPT(OpenMPIsTargetDevice, 1, false)
 /// Generate OpenMP target code only for GPUs
diff --git a/flang/include/flang/Tools/CrossToolHelpers.h b/flang/include/flang/Tools/CrossToolHelpers.h
index d9401e753fb7..1dbc18e2b348 100644
--- a/flang/include/flang/Tools/CrossToolHelpers.h
+++ b/flang/include/flang/Tools/CrossToolHelpers.h
@@ -165,7 +165,7 @@ struct OffloadModuleOpts {
   bool OpenMPIsTargetDevice = false;
   bool OpenMPIsGPU = false;
   bool OpenMPForceUSM = false;
-  uint32_t OpenMPVersion = 11;
+  uint32_t OpenMPVersion = 31;
   std::string OMPHostIRFile = {};
   std::vector<llvm::Triple> OMPTargetTriples = {};
   bool NoGPULib = false;
diff --git a/flang/lib/Frontend/CompilerInvocation.cpp b/flang/lib/Frontend/CompilerInvocation.cpp
index 1ea783474654..466d939b7b84 100644
--- a/flang/lib/Frontend/CompilerInvocation.cpp
+++ b/flang/lib/Frontend/CompilerInvocation.cpp
@@ -1108,8 +1108,8 @@ static bool parseOpenMPArgs(CompilerInvocation &res, llvm::opt::ArgList &args,
   unsigned numErrorsBefore = diags.getNumErrors();
   llvm::Triple t(res.getTargetOpts().triple);
 
-  // By default OpenMP is set to 1.1 version
-  res.getLangOpts().OpenMPVersion = 11;
+  // By default OpenMP is set to 3.1 version
+  res.getLangOpts().OpenMPVersion = 31;
   res.getFrontendOpts().features.Enable(
       Fortran::common::LanguageFeature::OpenMP);
   if (int Version = getLastArgIntValue(
diff --git a/flang/test/Driver/bbc-openmp-version-macro.f90 b/flang/test/Driver/bbc-openmp-version-macro.f90
index 7118021cba03..6fa19e1672ad 100644
--- a/flang/test/Driver/bbc-openmp-version-macro.f90
+++ b/flang/test/Driver/bbc-openmp-version-macro.f90
@@ -13,7 +13,7 @@
 ! RUN: bbc -fopenmp -fopenmp-version=51 -o - %s | FileCheck %s --check-prefix=OPENMP-VERSION-51
 ! RUN: bbc -fopenmp -fopenmp-version=52 -o - %s | FileCheck %s --check-prefix=OPENMP-VERSION-52
 
-! DEFAULT-OPENMP-VERSION: {{.*}} = arith.constant 199911 : i32
+! DEFAULT-OPENMP-VERSION: {{.*}} = arith.constant 201107 : i32
 ! OPENMP-VERSION-11: {{.*}} = arith.constant 199911 : i32
 ! OPENMP-VERSION-20: {{.*}} = arith.constant 200011 : i32
 ! OPENMP-VERSION-25: {{.*}} = arith.constant 200505 : i32
diff --git a/flang/test/Driver/flang-openmp-version-macro.f90 b/flang/test/Driver/flang-openmp-version-macro.f90
index 73cb322a06c0..95b3071544d0 100644
--- a/flang/test/Driver/flang-openmp-version-macro.f90
+++ b/flang/test/Driver/flang-openmp-version-macro.f90
@@ -13,7 +13,7 @@
 ! RUN: %flang_fc1 -fopenmp -fopenmp-version=51 -cpp -E %s | FileCheck %s --check-prefix=OPENMP-VERSION-51
 ! RUN: %flang_fc1 -fopenmp -fopenmp-version=52 -cpp -E %s | FileCheck %s --check-prefix=OPENMP-VERSION-52
 
-! DEFAULT-OPENMP-VERSION: integer :: var1 = 199911
+! DEFAULT-OPENMP-VERSION: integer :: var1 = 201107
 ! OPENMP-VERSION-11: integer :: var1 = 199911
 ! OPENMP-VERSION-20: integer :: var1 = 200011
 ! OPENMP-VERSION-25: integer :: var1 = 200505
diff --git a/flang/test/Lower/OpenMP/rtl-flags.f90 b/flang/test/Lower/OpenMP/rtl-flags.f90
index b38a6af0d7e3..8b0db5926479 100644
--- a/flang/test/Lower/OpenMP/rtl-flags.f90
+++ b/flang/test/Lower/OpenMP/rtl-flags.f90
@@ -20,7 +20,7 @@
 !RUN: bbc -emit-hlfir -fopenmp -fopenmp-assume-no-nested-parallelism -fopenmp-is-target-device -o - %s | FileCheck %s --check-prefix=NEST-PAR-DEVICE-FIR
 !RUN: bbc -emit-hlfir -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-target-device -o - %s | FileCheck %s --check-prefix=ALL-DEVICE-FIR
 
-!DEFAULT-DEVICE-FIR: module attributes {{{.*}}omp.flags = #omp.flags<openmp_device_version = 11>
+!DEFAULT-DEVICE-FIR: module attributes {{{.*}}omp.flags = #omp.flags<openmp_device_version = 31>
 !DEFAULT-DEVICE-FIR-SAME: omp.is_target_device = true
 !DEFAULT-DEVICE-FIR-VERSION: module attributes {{{.*}}omp.flags = #omp.flags<openmp_device_version = 45>
 !DEFAULT-DEVICE-FIR-VERSION-SAME: omp.is_target_device = true
@@ -28,12 +28,12 @@
 !DEFAULT-HOST-FIR: module attributes {{{.*}}omp.is_target_device = false{{.*}}
 !DEFAULT-HOST-FIR-VERSION: module attributes {{{.*}}omp.is_target_device = false
 !DEFAULT-HOST-FIR-VERSION-SAME: omp.version = #omp.version<version = 45>
-!DBG-DEVICE-FIR: module attributes {{{.*}}omp.flags = #omp.flags<debug_kind = 1, openmp_device_version = 11>
-!DBG-EQ-DEVICE-FIR: module attributes {{{.*}}omp.flags = #omp.flags<debug_kind = 111, openmp_device_version = 11>
-!TEAMS-OSUB-DEVICE-FIR: module attributes {{{.*}}omp.flags = #omp.flags<assume_teams_oversubscription = true, openmp_device_version = 11>
-!THREAD-OSUB-DEVICE-FIR: module attributes {{{.*}}omp.flags = #omp.flags<assume_threads_oversubscription = true, openmp_device_version = 11>
-!THREAD-STATE-DEVICE-FIR: module attributes {{{.*}}omp.flags = #omp.flags<assume_no_thread_state = true, openmp_device_version = 11>
-!NEST-PAR-DEVICE-FIR: module attributes {{{.*}}omp.flags = #omp.flags<assume_no_nested_parallelism = true, openmp_device_version = 11>
-!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, openmp_device_version = 11>
+!DBG-DEVICE-FIR: module attributes {{{.*}}omp.flags = #omp.flags<debug_kind = 1, openmp_device_version = 31>
+!DBG-EQ-DEVICE-FIR: module attributes {{{.*}}omp.flags = #omp.flags<debug_kind = 111, openmp_device_version = 31>
+!TEAMS-OSUB-DEVICE-FIR: module attributes {{{.*}}omp.flags = #omp.flags<assume_teams_oversubscription = true, openmp_device_version = 31>
+!THREAD-OSUB-DEVICE-FIR: module attributes {{{.*}}omp.flags = #omp.flags<assume_threads_oversubscription = true, openmp_device_version = 31>
+!THREAD-STATE-DEVICE-FIR: module attributes {{{.*}}omp.flags = #omp.flags<assume_no_thread_state = true, openmp_device_version = 31>
+!NEST-PAR-DEVICE-FIR: module attributes {{{.*}}omp.flags = #omp.flags<assume_no_nested_parallelism = true, openmp_device_version = 31>
+!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, openmp_device_version = 31>
 subroutine omp_subroutine()
 end subroutine omp_subroutine
diff --git a/flang/tools/bbc/bbc.cpp b/flang/tools/bbc/bbc.cpp
index c38e59f47c54..78ce510968ca 100644
--- a/flang/tools/bbc/bbc.cpp
+++ b/flang/tools/bbc/bbc.cpp
@@ -169,7 +169,7 @@ static llvm::cl::list<std::string> targetTriplesOpenMP(
 static llvm::cl::opt<uint32_t>
     setOpenMPVersion("fopenmp-version",
                      llvm::cl::desc("OpenMP standard version"),
-                     llvm::cl::init(11));
+                     llvm::cl::init(31));
 
 static llvm::cl::opt<uint32_t> setOpenMPTargetDebug(
     "fopenmp-target-debug",