[clang] [clang][OpenMP] Move "loop" directive mapping from sema to codegen (PR #99905)

[Alexey Bataev via cfe-commits]

================
@@ -2534,21 +2563,24 @@ static void emitCommonSimdLoop(CodeGenFunction &CGF, const OMPLoopDirective &S,
 static void emitOMPSimdRegion(CodeGenFunction &CGF, const OMPLoopDirective &S,
                               PrePostActionTy &Action) {
   Action.Enter(CGF);
-  assert(isOpenMPSimdDirective(S.getDirectiveKind()) &&
-         "Expected simd directive");
   OMPLoopScope PreInitScope(CGF, S);
   // if (PreCond) {
   //   for (IV in 0..LastIteration) BODY;
   //   <Final counter/linear vars updates>;
   // }
-  //
-  if (isOpenMPDistributeDirective(S.getDirectiveKind()) ||
-      isOpenMPWorksharingDirective(S.getDirectiveKind()) ||
-      isOpenMPTaskLoopDirective(S.getDirectiveKind())) {
-    (void)EmitOMPHelperVar(CGF, cast<DeclRefExpr>(S.getLowerBoundVariable()));
-    (void)EmitOMPHelperVar(CGF, cast<DeclRefExpr>(S.getUpperBoundVariable()));
+
+  // The presence of lower/upper bound variable depends on the actual directive
+  // kind in the AST node. The variables must be emitted because some of the
+  // expressions associated with the loop will use them.
+  OpenMPDirectiveKind DKind = S.getDirectiveKind();
+  if (isOpenMPDistributeDirective(DKind) ||
+      isOpenMPWorksharingDirective(DKind) || isOpenMPTaskLoopDirective(DKind) ||
+      isOpenMPGenericLoopDirective(DKind)) {
+    EmitOMPHelperVar(CGF, cast<DeclRefExpr>(S.getLowerBoundVariable()));
+    EmitOMPHelperVar(CGF, cast<DeclRefExpr>(S.getUpperBoundVariable()));
----------------
alexey-bataev wrote:

```suggestion
    (void)EmitOMPHelperVar(CGF, cast<DeclRefExpr>(S.getLowerBoundVariable()));
    (void)EmitOMPHelperVar(CGF, cast<DeclRefExpr>(S.getUpperBoundVariable()));
```


https://github.com/llvm/llvm-project/pull/99905