Revert "[flang][openacc] Check trip count invariance with other IVs (#79906)"

This reverts commit 0fa4463.

Breaks buildbot https://lab.llvm.org/buildbot/#/builders/268/builds/7155

Author: clementval

flang/lib/Semantics/resolve-directives.cpp

@@ -13,7 +13,6 @@
 #include "resolve-names-utils.h"
 #include "flang/Common/idioms.h"
 #include "flang/Evaluate/fold.h"
-#include "flang/Evaluate/tools.h"
 #include "flang/Evaluate/type.h"
 #include "flang/Parser/parse-tree-visitor.h"
 #include "flang/Parser/parse-tree.h"
@@ -267,7 +266,7 @@ class AccAttributeVisitor : DirectiveAttributeVisitor<llvm::acc::Directive> {
       Symbol::Flag::AccDevicePtr, Symbol::Flag::AccDeviceResident,
       Symbol::Flag::AccLink, Symbol::Flag::AccPresent};
 
-  void CheckAssociatedLoop(const parser::DoConstruct &);
+  void CheckAssociatedLoopIndex(const parser::OpenACCLoopConstruct &);
   void ResolveAccObjectList(const parser::AccObjectList &, Symbol::Flag);
   void ResolveAccObject(const parser::AccObject &, Symbol::Flag);
   Symbol *ResolveAcc(const parser::Name &, Symbol::Flag, Scope &);
@@ -883,8 +882,7 @@ bool AccAttributeVisitor::Pre(const parser::OpenACCLoopConstruct &x) {
   }
   ClearDataSharingAttributeObjects();
   SetContextAssociatedLoopLevel(GetAssociatedLoopLevelFromClauses(clauseList));
-  const auto &outer{std::get<std::optional<parser::DoConstruct>>(x.t)};
-  CheckAssociatedLoop(*outer);
+  CheckAssociatedLoopIndex(x);
   return true;
 }
 
@@ -1089,10 +1087,6 @@ bool AccAttributeVisitor::Pre(const parser::OpenACCCombinedConstruct &x) {
   default:
     break;
   }
-  const auto &clauseList{std::get<parser::AccClauseList>(beginBlockDir.t)};
-  SetContextAssociatedLoopLevel(GetAssociatedLoopLevelFromClauses(clauseList));
-  const auto &outer{std::get<std::optional<parser::DoConstruct>>(x.t)};
-  CheckAssociatedLoop(*outer);
   ClearDataSharingAttributeObjects();
   return true;
 }
@@ -1224,8 +1218,8 @@ std::int64_t AccAttributeVisitor::GetAssociatedLoopLevelFromClauses(
   return 1; // default is outermost loop
 }
 
-void AccAttributeVisitor::CheckAssociatedLoop(
-    const parser::DoConstruct &outerDoConstruct) {
+void AccAttributeVisitor::CheckAssociatedLoopIndex(
+    const parser::OpenACCLoopConstruct &x) {
   std::int64_t level{GetContext().associatedLoopLevel};
   if (level <= 0) { // collapse value was negative or 0
     return;
@@ -1256,41 +1250,10 @@ void AccAttributeVisitor::CheckAssociatedLoop(
     return nullptr;
   };
 
-  auto checkExprHasSymbols = [&](llvm::SmallVector<Symbol *> &ivs,
-                                 semantics::UnorderedSymbolSet &symbols) {
-    for (auto iv : ivs) {
-      if (symbols.count(*iv) != 0) {
-        context_.Say(GetContext().directiveSource,
-            "Trip count must be computable and invariant"_err_en_US);
-      }
-    }
-  };
-
-  Symbol::Flag flag;
-  llvm::SmallVector<Symbol *> ivs;
-  using Bounds = parser::LoopControl::Bounds;
-  for (const parser::DoConstruct *loop{&outerDoConstruct}; loop && level > 0;) {
+  const auto &outer{std::get<std::optional<parser::DoConstruct>>(x.t)};
+  for (const parser::DoConstruct *loop{&*outer}; loop && level > 0;) {
     // Go through all nested loops to ensure index variable exists.
-    if (const parser::Name * ivName{GetLoopIndex(*loop)}) {
-      if (auto *symbol{ResolveAcc(*ivName, flag, currScope())}) {
-        if (auto &control{loop->GetLoopControl()}) {
-          if (const Bounds * b{std::get_if<Bounds>(&control->u)}) {
-            if (auto lowerExpr{semantics::AnalyzeExpr(context_, b->lower)}) {
-              semantics::UnorderedSymbolSet lowerSyms =
-                  evaluate::CollectSymbols(*lowerExpr);
-              checkExprHasSymbols(ivs, lowerSyms);
-            }
-            if (auto upperExpr{semantics::AnalyzeExpr(context_, b->upper)}) {
-              semantics::UnorderedSymbolSet upperSyms =
-                  evaluate::CollectSymbols(*upperExpr);
-              checkExprHasSymbols(ivs, upperSyms);
-            }
-          }
-        }
-        ivs.push_back(symbol);
-      }
-    }
-
+    GetLoopIndex(*loop);
     const auto &block{std::get<parser::Block>(loop->t)};
     --level;
     loop = getNextDoConstruct(block, level);

flang/test/Semantics/OpenACC/acc-loop.f90

@@ -10,10 +10,9 @@ program openacc_loop_validity
   type atype
     real(8), dimension(10) :: arr
     real(8) :: s
-    integer :: n
   end type atype
 
-  integer :: i, j, k, b, gang_size, vector_size, worker_size
+  integer :: i, j, b, gang_size, vector_size, worker_size
   integer, parameter :: N = 256
   integer, dimension(N) :: c
   logical, dimension(N) :: d, e
@@ -318,41 +317,4 @@ program openacc_loop_validity
     END DO
   END DO
 
-  !ERROR: Trip count must be computable and invariant
-  !$acc loop collapse(2)
-  DO i = 1, n
-    DO j = 1, c(i)
-    END DO
-  END DO
-
-  !ERROR: Trip count must be computable and invariant
-  !$acc loop collapse(2)
-  DO i = 1, n
-    DO j = 1, i
-    END DO
-  END DO
-
-  !ERROR: Trip count must be computable and invariant
-  !$acc loop collapse(2)
-  DO i = 1, n
-    DO j = 1, ta(i)%n
-    END DO
-  END DO
-
-  !ERROR: Trip count must be computable and invariant
-  !$acc parallel loop collapse(2)
-  DO i = 1, n
-    DO j = 1, ta(i)%n
-    END DO
-  END DO
-
-  !ERROR: Trip count must be computable and invariant
-  !$acc loop collapse(3)
-  DO i = 1, n
-    DO j = 1, n
-      DO k = 1, i
-      END DO
-    END DO
-  END DO
-
 end program openacc_loop_validity