looprange clause semantics

Author: Ferran Toda

flang/lib/Lower/OpenMP/Clauses.cpp

@@ -1038,7 +1038,7 @@ Link make(const parser::OmpClause::Link &inp,
 
 LoopRange make(const parser::OmpClause::Looprange &inp,
                semantics::SemanticsContext &semaCtx) {
-  llvm_unreachable("Unimplemented: looprange");
+  TODO_NOLOC("looprange clause");
 }
 
 Map make(const parser::OmpClause::Map &inp,

flang/lib/Semantics/check-omp-loop.cpp

@@ -305,6 +305,9 @@ void OmpStructureChecker::Enter(const parser::OpenMPLoopConstruct &x) {
       beginName.v == llvm::omp::Directive::OMPD_distribute_simd) {
     CheckDistLinear(x);
   }
+  if (beginName.v == llvm::omp::Directive::OMPD_fuse) {
+    CheckLooprangeBounds(x);
+  }
 }
 
 const parser::Name OmpStructureChecker::GetLoopIndex(
@@ -453,6 +456,32 @@ void OmpStructureChecker::CheckDistLinear(
   }
 }
 
+void OmpStructureChecker::CheckLooprangeBounds(
+    const parser::OpenMPLoopConstruct &x) {
+  const parser::OmpClauseList &clauseList = x.BeginDir().Clauses();
+  if (!clauseList.v.empty()) {
+    for (auto &clause : clauseList.v) {
+      if (const auto *lrClause{
+              std::get_if<parser::OmpClause::Looprange>(&clause.u)}) {
+        if (const auto first{GetIntValue(std::get<0>((lrClause->v).t))}) {
+          if (const auto count{GetIntValue(std::get<1>((lrClause->v).t))}) {
+            auto &loopConsList =
+                std::get<std::list<parser::NestedConstruct>>(x.t);
+            if (loopConsList.size() < (unsigned)(*first + *count - 1)) {
+              context_.Say(clause.source,
+                  "The loop range indicated in the %s clause"
+                  " must not be out of the bounds of the Loop Sequence"
+                  " following the construct."_err_en_US,
+                  parser::ToUpperCaseLetters(clause.source.ToString()));
+            }
+          }
+        }
+        return;
+      }
+    }
+  }
+}
+
 void OmpStructureChecker::Leave(const parser::OpenMPLoopConstruct &x) {
   const parser::OmpClauseList &clauseList{x.BeginDir().Clauses()};
 

flang/lib/Semantics/check-omp-structure.cpp

@@ -3107,9 +3107,11 @@ CHECK_REQ_CONSTANT_SCALAR_INT_CLAUSE(Safelen, OMPC_safelen)
 CHECK_REQ_CONSTANT_SCALAR_INT_CLAUSE(Simdlen, OMPC_simdlen)
 
 void OmpStructureChecker::Enter(const parser::OmpClause::Looprange &x) {
-  context_.Say(GetContext().clauseSource,
-      "LOOPRANGE clause is not implemented yet"_err_en_US,
-      ContextDirectiveAsFortran());
+  CheckAllowedClause(llvm::omp::Clause::OMPC_looprange);
+  auto &first = std::get<0>(x.v.t);
+  auto &count = std::get<1>(x.v.t);
+  RequiresConstantPositiveParameter(llvm::omp::Clause::OMPC_looprange, count);
+  RequiresConstantPositiveParameter(llvm::omp::Clause::OMPC_looprange, first);
 }
 
 // Restrictions specific to each clause are implemented apart from the

flang/lib/Semantics/check-omp-structure.h

@@ -297,6 +297,7 @@ class OmpStructureChecker
   void CheckAtomicWrite(const parser::OpenMPAtomicConstruct &x);
   void CheckAtomicUpdate(const parser::OpenMPAtomicConstruct &x);
 
+  void CheckLooprangeBounds(const parser::OpenMPLoopConstruct &x);
   void CheckDistLinear(const parser::OpenMPLoopConstruct &x);
   void CheckSIMDNest(const parser::OpenMPConstruct &x);
   void CheckTargetNest(const parser::OpenMPConstruct &x);

flang/test/Parser/OpenMP/fuse-looprange.f90

@@ -0,0 +1,38 @@
+! RUN: %flang_fc1 -fdebug-unparse -fopenmp -fopenmp-version=60 %s | FileCheck --ignore-case %s
+! RUN: %flang_fc1 -fdebug-dump-parse-tree -fopenmp -fopenmp-version=60  %s | FileCheck --check-prefix="PARSE-TREE" %s
+
+subroutine openmp_fuse(x)
+
+  integer, intent(inout)::x
+
+!CHECK: !$omp fuse looprange
+!$omp  fuse looprange(1,2)
+!CHECK: do
+  do x = 1, 100
+  	call F1()
+!CHECK: end do
+  end do
+!CHECK: do
+  do x = 1, 100
+  	call F1()
+!CHECK: end do
+  end do
+!CHECK: do
+  do x = 1, 100
+  	call F1()
+!CHECK: end do
+  end do
+!CHECK: !$omp end fuse
+!$omp end fuse
+
+!PARSE-TREE: OpenMPConstruct -> OpenMPLoopConstruct
+!PARSE-TREE: OmpBeginLoopDirective
+!PARSE-TREE: OmpDirectiveName -> llvm::omp::Directive = fuse
+!PARSE-TREE: OmpClauseList -> OmpClause -> Looprange -> OmpLoopRangeClause
+!PARSE-TREE: Scalar -> Integer -> Constant -> Expr = '1_4'
+!PARSE-TREE: LiteralConstant -> IntLiteralConstant = '1'
+!PARSE-TREE: Scalar -> Integer -> Constant -> Expr = '2_4'
+!PARSE-TREE: LiteralConstant -> IntLiteralConstant = '2'
+
+END subroutine openmp_fuse
+

flang/test/Semantics/OpenMP/loop-transformation-clauses01.f90

@@ -0,0 +1,31 @@
+! Testing the Semantics of clauses on loop transformation directives
+
+!RUN: %python %S/../test_errors.py %s %flang -fopenmp -fopenmp-version=60
+
+
+subroutine loop_transformation_construct1
+  implicit none
+  integer, parameter:: i = 5
+  integer :: x
+  integer :: v(i)
+
+  !$omp fuse looprange(1,2)
+  do x = 1, i
+    v(x) = x * 2
+  end do
+  do x = 1, i
+    v(x) = x * 2
+  end do
+  !$omp end fuse
+
+  !ERROR: The loop range indicated in the LOOPRANGE(5,2) clause must not be out of the bounds of the Loop Sequence following the construct.
+  !$omp fuse looprange(5,2)
+  do x = 1, i
+    v(x) = x * 2
+  end do
+  do x = 1, i
+    v(x) = x * 2
+  end do
+  !$omp end fuse
+end subroutine
+