testing: addition addition_precision sum of two precisions with sum lower than 2^24

test/test_addition.c

@@ -6,10 +6,12 @@
 
 num carry[1];
 
+unsigned int e = 8388608;
+
 union {
     float floating;
     unsigned int integer;
-} number[5];
+} number[6];
 
 void setUp(void)
 {
@@ -189,6 +191,26 @@ void test_addition_exponentfloatingnumber(void)
     TEST_ASSERT_EQUAL_UINT(expected[4], result[4]);
 }
 
+void test_addition_addition_precision_positivnumberlowerthan2tothepowerof24(void)
+{
+    unsigned int result[2];
+    number[0].floating = 652468761.2348, number[1].floating = 2.675312546943, number[2].floating = 321647956212.2146, number[3].floating = 0.00000324567861, number[4].floating = number[0].floating + number[1].floating; number[5].floating = number[2].floating + number[3].floating;
+    unsigned int expected[2] = { precision(number[4].integer), precision(number[5].integer) };
+
+    unsigned int e0, e1, e2, e3, p0, p1, p2, p3;
+
+    e0 = exponent(number[0].integer), e1 = exponent(number[1].integer), e2 = exponent(number[2].integer), e3 = exponent(number[3].integer);
+    p0 = precision(number[0].integer) | e, p1 = precision(number[1].integer) | e, p2 = precision(number[2].integer) | e, p3 = precision(number[3].integer) | e;
+
+    p1 >>= e0 - e1, p3 >>= e2 - e3;
+
+    result[0] = addition_precision( p0, p1 ) ^ e;
+    result[1] = addition_precision( p2, p3 ) ^ e;
+
+    TEST_ASSERT_EQUAL_UINT(expected[0], result[0]);
+    TEST_ASSERT_EQUAL_UINT(expected[1], result[1]);
+}
+
 void test_addition_output_numberwithsignexponentprecision(void)
 {
     unsigned int result[5];