# --- T2-COPYRIGHT-BEGIN ---
# t2/package/*/gcc/hotfix-revert-atomics.patch.microblaze
# Copyright (C) 2024 - 2026 The T2 SDE Project
# SPDX-License-Identifier: GPL-2.0 or patched project license
# --- T2-COPYRIGHT-END ---

diff --git a/gcc/builtins.cc b/gcc/builtins.cc
index 40dfd36a319..6e4274bb2a4 100644
--- a/gcc/builtins.cc
+++ b/gcc/builtins.cc
@@ -8387,10 +8387,7 @@ expand_builtin (tree exp, rtx target, rtx subtarget, machine_mode mode,
       break;
 
     case BUILT_IN_ATOMIC_TEST_AND_SET:
-      target = expand_builtin_atomic_test_and_set (exp, target);
-      if (target)
-	return target;
-      break;
+      return expand_builtin_atomic_test_and_set (exp, target);
 
     case BUILT_IN_ATOMIC_CLEAR:
       return expand_builtin_atomic_clear (exp);
diff --git a/gcc/optabs.cc b/gcc/optabs.cc
index e1898da2280..8b96f23aec0 100644
--- a/gcc/optabs.cc
+++ b/gcc/optabs.cc
@@ -7080,17 +7080,25 @@ expand_atomic_test_and_set (rtx target, rtx mem, enum memmodel model)
   /* Recall that the legacy lock_test_and_set optab was allowed to do magic
      things with the value 1.  Thus we try again without trueval.  */
   if (!ret && targetm.atomic_test_and_set_trueval != 1)
+    ret = maybe_emit_sync_lock_test_and_set (subtarget, mem, const1_rtx, model);
+
+  /* Failing all else, assume a single threaded environment and simply
+     perform the operation.  */
+  if (!ret)
     {
-      ret = maybe_emit_sync_lock_test_and_set (subtarget, mem, const1_rtx, model);
+      /* If the result is ignored skip the move to target.  */
+      if (subtarget != const0_rtx)
+        emit_move_insn (subtarget, mem);
 
-      if (ret)
-	{
-	  /* Rectify the not-one trueval.  */
-	  ret = emit_store_flag_force (target, NE, ret, const0_rtx, mode, 0, 1);
-	  gcc_assert (ret);
-	}
+      emit_move_insn (mem, trueval);
+      ret = subtarget;
     }
 
+  /* Recall that have to return a boolean value; rectify if trueval
+     is not exactly one.  */
+  if (targetm.atomic_test_and_set_trueval != 1)
+    ret = emit_store_flag_force (target, NE, ret, const0_rtx, mode, 0, 1);
+  
   return ret;
 }