add int/int -> long specialization for int multiply

Author: lukasstadler

graalpython/com.oracle.graal.python/src/com/oracle/graal/python/builtins/objects/ints/IntBuiltins.java

@@ -567,6 +567,11 @@ int doII(int x, int y) throws ArithmeticException {
             return Math.multiplyExact(x, y);
         }
 
+        @Specialization(replaces = "doII")
+        long doIIL(int x, int y) {
+            return x * (long) y;
+        }
+
         @Specialization(rewriteOn = ArithmeticException.class)
         long doLL(long x, long y) {
             return Math.multiplyExact(x, y);