[flang-commits] [flang] 15ad4d0 - [flang][OpenMP]Fix versioning for implicit linear clause (#181791)

[via flang-commits]

Author: NimishMishra
Date: 2026-02-18T11:55:00-08:00
New Revision: 15ad4d08776bcf1c71cc65ea8df54279774db96a

URL: https://github.com/llvm/llvm-project/commit/15ad4d08776bcf1c71cc65ea8df54279774db96a
DIFF: https://github.com/llvm/llvm-project/commit/15ad4d08776bcf1c71cc65ea8df54279774db96a.diff

LOG: [flang][OpenMP]Fix versioning for implicit linear clause (#181791)

The versioning of the implicit linear clause was set at OpenMP 4.5.
However, versions v5.0 and v5.2 also allow implicit linearisation, which
was missed earlier. This PR fixes this.

OpenMP v5.0 (2.19.1.1) : "_The loop iteration variable in the associated
do-loop of a simd construct with just one associated do-loop is linear
with a linear-step that is the increment of the associated do-loop_."

OpenMP v5.2 (5.1.1) : "_The loop iteration variable in the associated
loop of a simd construct with just one associated loop is linear with a
linear-step that is the increment of the associated loop_"

OpenMP v6.0 (7.1.1) : "_The loop-iteration variable in any affected loop
of a loop or simd construct is lastprivate_."


Fixes: https://github.com/llvm/llvm-project/issues/179345

Added: 
    flang/test/Semantics/OpenMP/implicit_linear_symbols.f90

Modified: 
    flang/lib/Semantics/resolve-directives.cpp
    flang/test/Lower/OpenMP/order-clause.f90
    flang/test/Lower/OpenMP/simd-linear.f90
    flang/test/Lower/OpenMP/simd.f90

Removed: 
    


################################################################################
diff  --git a/flang/lib/Semantics/resolve-directives.cpp b/flang/lib/Semantics/resolve-directives.cpp
index 1fde0d62581e8..ba645033df60f 100644
--- a/flang/lib/Semantics/resolve-directives.cpp
+++ b/flang/lib/Semantics/resolve-directives.cpp
@@ -2443,7 +2443,7 @@ void OmpAttributeVisitor::PrivatizeAssociatedLoopIndexAndCheckLoopLevel(
   unsigned version{context_.langOptions().OpenMPVersion};
   if (!llvm::omp::allSimdSet.test(GetContext().directive)) {
     ivDSA = Symbol::Flag::OmpPrivate;
-  } else if (level == 1 && version <= 45) {
+  } else if (level == 1 && version < 60) {
     ivDSA = Symbol::Flag::OmpLinear;
   } else {
     ivDSA = Symbol::Flag::OmpLastPrivate;

diff  --git a/flang/test/Lower/OpenMP/order-clause.f90 b/flang/test/Lower/OpenMP/order-clause.f90
index d5799079b3759..e1b93a2b8f7a2 100644
--- a/flang/test/Lower/OpenMP/order-clause.f90
+++ b/flang/test/Lower/OpenMP/order-clause.f90
@@ -1,6 +1,8 @@
 ! This test checks lowering of OpenMP order clause.
 
-!RUN: %flang_fc1 -emit-hlfir -fopenmp -fopenmp-version=50 %s -o - | FileCheck %s
+! To prevent testing for unrelated clauses like implicit linear clause and focusing on the
+! clauses of interest here, the OpenMP version is 6.0
+!RUN: %flang_fc1 -emit-hlfir -fopenmp -fopenmp-version=60 %s -o - | FileCheck %s
 
 !CHECK-LABEL:   func.func @_QPsimd_order() {
 subroutine simd_order

diff  --git a/flang/test/Lower/OpenMP/simd-linear.f90 b/flang/test/Lower/OpenMP/simd-linear.f90
index 6a50f1da18489..2caf1b0ad05fa 100644
--- a/flang/test/Lower/OpenMP/simd-linear.f90
+++ b/flang/test/Lower/OpenMP/simd-linear.f90
@@ -1,7 +1,7 @@
 ! This test checks lowering of OpenMP SIMD Directive
 ! with linear clause
 
-! RUN: %flang_fc1 -fopenmp -emit-hlfir -fopenmp-version=50 %s -o - 2>&1 | FileCheck %s
+! RUN: %flang_fc1 -fopenmp -emit-hlfir -fopenmp-version=60 %s -o - 2>&1 | FileCheck %s
 ! RUN: %flang_fc1 -fopenmp -emit-hlfir -fopenmp-version=45 %s -o - 2>&1 | FileCheck %s --check-prefix=IMPLICIT
 
 !CHECK: %[[X_alloca:.*]] = fir.alloca i32 {bindc_name = "x", uniq_name = "_QFsimple_linearEx"}

diff  --git a/flang/test/Lower/OpenMP/simd.f90 b/flang/test/Lower/OpenMP/simd.f90
index a3af7628c29f5..ff0bd6dd0a730 100644
--- a/flang/test/Lower/OpenMP/simd.f90
+++ b/flang/test/Lower/OpenMP/simd.f90
@@ -1,8 +1,11 @@
 ! Tests for 2.9.3.1 Simd
 
 ! The "if" clause was added to the "simd" directive in OpenMP 5.0.
-! RUN: %flang_fc1 -flang-experimental-hlfir -emit-hlfir -fopenmp -fopenmp-version=50 %s -o - | FileCheck %s
-! RUN: bbc -hlfir -emit-hlfir -fopenmp -fopenmp-version=50 %s -o - | FileCheck %s
+
+! To prevent testing for unrelated clauses like implicit linear clause and focusing on the
+! clauses of interest here, the OpenMP version is 6.0
+! RUN: %flang_fc1 -flang-experimental-hlfir -emit-hlfir -fopenmp -fopenmp-version=60 %s -o - | FileCheck %s
+! RUN: bbc -hlfir -emit-hlfir -fopenmp -fopenmp-version=60 %s -o - | FileCheck %s
 
 !CHECK: omp.declare_reduction @[[REDUCER:.*]] : i32
 

diff  --git a/flang/test/Semantics/OpenMP/implicit_linear_symbols.f90 b/flang/test/Semantics/OpenMP/implicit_linear_symbols.f90
new file mode 100644
index 0000000000000..e57a063d8a9d0
--- /dev/null
+++ b/flang/test/Semantics/OpenMP/implicit_linear_symbols.f90
@@ -0,0 +1,15 @@
+!RUN: %flang_fc1 -fopenmp -fopenmp-version=52 -fdebug-dump-symbols %s 2>&1 | FileCheck %s --check-prefix=IMPLICIT
+!RUN: %flang_fc1 -fopenmp -fopenmp-version=60 -fdebug-dump-symbols %s 2>&1 | FileCheck %s --check-prefix=NOIMPLICIT
+
+
+!IMPLICIT: k2 (OmpLinear, OmpPreDetermined): {{.*}}
+!NOIMPLICIT: k2 (OmpLastPrivate, OmpPreDetermined): {{.*}}
+subroutine implicit_linear
+  integer :: k1, k2
+
+  !$omp simd
+  do k2=1,10
+  do k1=1,10
+  end do
+  end do
+end subroutine