[flang][openmp] Don't mark loop variables with explicit DSA as predetermined (#68723)

This patch fixes a bug where loop variables are always marked as
predetermined
even when they have an explicit data sharing attribute specified.

Author: DavidTruby

flang/lib/Semantics/resolve-directives.cpp

@@ -1542,7 +1542,10 @@ void OmpAttributeVisitor::ResolveSeqLoopIndexInParallelOrTaskConstruct(
   }
   if (auto *symbol{ResolveOmp(iv, Symbol::Flag::OmpPrivate, targetIt->scope)}) {
     targetIt++;
-    symbol->set(Symbol::Flag::OmpPreDetermined);
+    // If this object already had a DSA then it is not predetermined
+    if (!IsObjectWithDSA(*symbol)) {
+      symbol->set(Symbol::Flag::OmpPreDetermined);
+    }
     iv.symbol = symbol; // adjust the symbol within region
     for (auto it{dirContext_.rbegin()}; it != targetIt; ++it) {
       AddToContextObjectWithDSA(*symbol, Symbol::Flag::OmpPrivate, *it);

flang/test/Lower/OpenMP/FIR/parallel-private-clause-fixes.f90

@@ -7,9 +7,9 @@
 ! CHECK:         %[[VAL_1:.*]] = fir.alloca i32 {bindc_name = "j", uniq_name = "_QFmultiple_private_fixEj"}
 ! CHECK:         %[[VAL_2:.*]] = fir.alloca i32 {bindc_name = "x", uniq_name = "_QFmultiple_private_fixEx"}
 ! CHECK:         omp.parallel {
-! CHECK:           %[[PRIV_J:.*]] = fir.alloca i32 {bindc_name = "j", pinned
-! CHECK:           %[[PRIV_I:.*]] = fir.alloca i32 {adapt.valuebyref, pinned
-! CHECK:           %[[PRIV_X:.*]] = fir.alloca i32 {bindc_name = "x", pinned
+! CHECK-DAG:           %[[PRIV_J:.*]] = fir.alloca i32 {bindc_name = "j", pinned
+! CHECK-DAG:           %[[PRIV_I:.*]] = fir.alloca i32 {adapt.valuebyref, pinned
+! CHECK-DAG:           %[[PRIV_X:.*]] = fir.alloca i32 {bindc_name = "x", pinned
 ! CHECK:           %[[ONE:.*]] = arith.constant 1 : i32
 ! CHECK:           %[[VAL_3:.*]] = fir.load %[[VAL_4:.*]] : !fir.ref<i32>
 ! CHECK:           %[[VAL_5:.*]] = arith.constant 1 : i32

flang/test/Semantics/OpenMP/do05-positivecase.f90

@@ -33,4 +33,13 @@ program omp_do
   !$omp end do
   !$omp end parallel
 
+  !$omp parallel private(i)
+  !DEF: /omp_do/OtherConstruct3/i (OmpPrivate) HostAssoc INTEGER(4)
+  do i=1,10
+     !$omp single
+     print *, "hello"
+     !$omp end single
+  end do
+  !$omp end parallel
+
 end program omp_do

flang/test/Semantics/OpenMP/symbol08.f90

@@ -67,7 +67,7 @@ subroutine test_pardo
     do j=6,10
    !REF: /test_pardo/a
    a(1,1,1) = 0.
-   !DEF: /test_pardo/OtherConstruct1/k (OmpPrivate, OmpPreDetermined) HostAssoc INTEGER(4)
+   !DEF: /test_pardo/OtherConstruct1/k (OmpPrivate) HostAssoc INTEGER(4)
    do k=11,15
     !REF: /test_pardo/a
     !REF: /test_pardo/OtherConstruct1/k
@@ -91,7 +91,7 @@ subroutine test_taskloop
 !$omp taskloop  private(j)
  !DEF: /test_taskloop/OtherConstruct1/i (OmpPrivate, OmpPreDetermined) HostAssoc INTEGER(4)
  do i=1,5
-  !DEF: /test_taskloop/OtherConstruct1/j (OmpPrivate, OmpPreDetermined) HostAssoc INTEGER(4)
+  !DEF: /test_taskloop/OtherConstruct1/j (OmpPrivate) HostAssoc INTEGER(4)
   !REF: /test_taskloop/OtherConstruct1/i
   do j=1,i
    !REF: /test_taskloop/a