Do not expand ILM instructions for second nest level

Pragma target teams distribute parallel do consists of
two levels of parallelism (teams and threads).

Threads from one team should be launched in parallel
via __kmpc_parallel_51 function. The code which is
executed by threads should be outlined to separate function.

Signed-off-by: Dominik Adamski <[email protected]>

Author: DominikAdamski

tools/flang2/flang2exe/expand.cpp

@@ -558,6 +558,9 @@ eval_ilm_check_if_skip(int ilmx, int *skip_expand, int *process_expanded)
       tmp,     /* temporary				 */
       op1;     /* operand 1				 */
   ILM_OP opcx; /**< ILM opcode of the ILM */
+  static int mp_loop_nest_level;
+  const int mp_loop_second_nest_level = 2;
+  static bool omit_loop_nesting;
 
   int first_op = 0;
 
@@ -582,6 +585,24 @@ eval_ilm_check_if_skip(int ilmx, int *skip_expand, int *process_expanded)
   if (EXPDBG(8, 2))
     fprintf(gbl.dbgfil, "---------- eval ilm  %d\n", ilmx);
 
+  if (flg.omptarget && gbl.ompaccel_intarget && !ll_ilm_is_rewriting()) {
+    if (opcx == IM_MPLOOP) {
+      if (++mp_loop_nest_level == mp_loop_second_nest_level) {
+        omit_loop_nesting = true;
+      }
+    }
+  else if ((opcx == IM_MPLOOPFINI) &&
+           (mp_loop_nest_level == mp_loop_second_nest_level)) {
+    if (omit_loop_nesting) {
+      omit_loop_nesting = false;
+    }
+  }
+  else if (omit_loop_nesting)
+  {
+    //Do not expand ilm instructions for 2nd level of parallelism
+    return sptr1;
+  }
+ }
   if (!ll_ilm_is_rewriting())
   {
 #ifdef OMP_OFFLOAD_LLVM