Details wrt parallel recompilation.

test/mjsunit/parallel-optimize-disabled.js

Index: test/mjsunit/parallel-optimize-disabled.js
diff --git a/test/mjsunit/regress/regress-2451.js b/test/mjsunit/parallel-optimize-disabled.js
similarity index 83%
copy from test/mjsunit/regress/regress-2451.js
copy to test/mjsunit/parallel-optimize-disabled.js
index 465e4e68c26f3e3e119cbaf82d50c8f83c6efa9a..2487964bd99a5497c9166c52fe8de4862ac55ba9 100644
--- a/test/mjsunit/regress/regress-2451.js
+++ b/test/mjsunit/parallel-optimize-disabled.js
@@ -25,17 +25,22 @@
 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
+// Flags: --nodead-code-elimination --parallel-recompilation
 // Flags: --allow-natives-syntax
 
-function f() {
-  assertEquals(-1.0, Math.round(-1.5));
-  assertEquals(-2.0, Math.round(-2.5));
-  assertEquals(-1.0, Math.round(-0.5000000000000001));
+function g() {  // g() cannot be optimized.
+  const x = 1;
+  x++;
+}
+
+function f(x) {
+  g();
 }
 
 f();
 f();
+%OptimizeFunctionOnNextCall(g, "parallel");
 %OptimizeFunctionOnNextCall(f);
-f();
-assertTrue(%GetOptimizationStatus(f) != 2);
+f(0);  // g() is disabled for optimization on inlining attempt.
+g();  // Attempt to optimize g() should not run into any assertion.