diff --git a/tests/suites/test_suite_mpi.data b/tests/suites/test_suite_mpi.data
index 202df1d29..212c2f3e2 100644
--- a/tests/suites/test_suite_mpi.data
+++ b/tests/suites/test_suite_mpi.data
@@ -445,12 +445,6 @@ mbedtls_mpi_add_abs:10:"-12345678":10:"-642531":10:"12988209"
 Test mbedtls_mpi_add_abs #1
 mbedtls_mpi_add_abs:10:"-643808006803554439230129854961492699151386107534013432918073439524138264842370630061369715394739134090922937332590384720397133335969549256322620979036686633213903952966175107096769180017646161851573147596390153":10:"56125680981752282333498088313568935051383833838594899821664631784577337171193624243181360054669678410455329112434552942717084003541384594864129940145043086760031292483340068923506115878221189886491132772739661669044958531131327771":10:"56125680981752282334141896320372489490613963693556392520816017892111350604111697682705498319512049040516698827829292076808006940873974979584527073481012636016353913462376755556720019831187364993587901952757307830896531678727717924"
 
-Test mbedtls_mpi_add_abs #2 (add to first value)
-mpi_add_abs_add_first:10:"123123":10:"123123":10:"246246"
-
-Test mbedtls_mpi_add_abs #3 (add to second value)
-mpi_add_abs_add_second:10:"123123":10:"123123":10:"246246"
-
 Regression mbedtls_mpi_add_abs (add small to very large MPI with carry rollover) [#1]
 mbedtls_mpi_add_abs:16:"FFFFFFFFFFFFFFFFFFFFFFFFFFFFF8":16:"08":16:"1000000000000000000000000000000"
 
diff --git a/tests/suites/test_suite_mpi.function b/tests/suites/test_suite_mpi.function
index 2b2daf652..84367428c 100644
--- a/tests/suites/test_suite_mpi.function
+++ b/tests/suites/test_suite_mpi.function
@@ -829,6 +829,15 @@ void mbedtls_mpi_add_mpi( int radix_X, char * input_X, int radix_Y,
     TEST_ASSERT( mbedtls_mpi_add_mpi( &Z, &X, &Y ) == 0 );
     TEST_ASSERT( mbedtls_mpi_cmp_mpi( &Z, &A ) == 0 );
 
+    /* result == first operand */
+    TEST_ASSERT( mbedtls_mpi_add_mpi( &X, &X, &Y ) == 0 );
+    TEST_ASSERT( mbedtls_mpi_cmp_mpi( &X, &A ) == 0 );
+    TEST_ASSERT( mbedtls_mpi_read_string( &X, radix_X, input_X ) == 0 );
+
+    /* result == second operand */
+    TEST_ASSERT( mbedtls_mpi_add_mpi( &Y, &X, &Y ) == 0 );
+    TEST_ASSERT( mbedtls_mpi_cmp_mpi( &Y, &A ) == 0 );
+
 exit:
     mbedtls_mpi_free( &X ); mbedtls_mpi_free( &Y ); mbedtls_mpi_free( &Z ); mbedtls_mpi_free( &A );
 }
@@ -874,44 +883,17 @@ void mbedtls_mpi_add_abs( int radix_X, char * input_X, int radix_Y,
     TEST_ASSERT( mbedtls_mpi_add_abs( &Z, &X, &Y ) == 0 );
     TEST_ASSERT( mbedtls_mpi_cmp_mpi( &Z, &A ) == 0 );
 
-exit:
-    mbedtls_mpi_free( &X ); mbedtls_mpi_free( &Y ); mbedtls_mpi_free( &Z ); mbedtls_mpi_free( &A );
-}
-/* END_CASE */
-
-/* BEGIN_CASE */
-void mpi_add_abs_add_first( int radix_X, char * input_X, int radix_Y,
-                            char * input_Y, int radix_A, char * input_A )
-{
-    mbedtls_mpi X, Y, A;
-    mbedtls_mpi_init( &X ); mbedtls_mpi_init( &Y ); mbedtls_mpi_init( &A );
-
-    TEST_ASSERT( mbedtls_mpi_read_string( &X, radix_X, input_X ) == 0 );
-    TEST_ASSERT( mbedtls_mpi_read_string( &Y, radix_Y, input_Y ) == 0 );
-    TEST_ASSERT( mbedtls_mpi_read_string( &A, radix_A, input_A ) == 0 );
+    /* result == first operand */
     TEST_ASSERT( mbedtls_mpi_add_abs( &X, &X, &Y ) == 0 );
     TEST_ASSERT( mbedtls_mpi_cmp_mpi( &X, &A ) == 0 );
-
-exit:
-    mbedtls_mpi_free( &X ); mbedtls_mpi_free( &Y ); mbedtls_mpi_free( &A );
-}
-/* END_CASE */
-
-/* BEGIN_CASE */
-void mpi_add_abs_add_second( int radix_X, char * input_X, int radix_Y,
-                             char * input_Y, int radix_A, char * input_A )
-{
-    mbedtls_mpi X, Y, A;
-    mbedtls_mpi_init( &X ); mbedtls_mpi_init( &Y ); mbedtls_mpi_init( &A );
-
     TEST_ASSERT( mbedtls_mpi_read_string( &X, radix_X, input_X ) == 0 );
-    TEST_ASSERT( mbedtls_mpi_read_string( &Y, radix_Y, input_Y ) == 0 );
-    TEST_ASSERT( mbedtls_mpi_read_string( &A, radix_A, input_A ) == 0 );
+
+    /* result == second operand */
     TEST_ASSERT( mbedtls_mpi_add_abs( &Y, &X, &Y ) == 0 );
     TEST_ASSERT( mbedtls_mpi_cmp_mpi( &Y, &A ) == 0 );
 
 exit:
-    mbedtls_mpi_free( &X ); mbedtls_mpi_free( &Y ); mbedtls_mpi_free( &A );
+    mbedtls_mpi_free( &X ); mbedtls_mpi_free( &Y ); mbedtls_mpi_free( &Z ); mbedtls_mpi_free( &A );
 }
 /* END_CASE */
 
@@ -945,6 +927,15 @@ void mbedtls_mpi_sub_mpi( int radix_X, char * input_X, int radix_Y,
     TEST_ASSERT( mbedtls_mpi_sub_mpi( &Z, &X, &Y ) == 0 );
     TEST_ASSERT( mbedtls_mpi_cmp_mpi( &Z, &A ) == 0 );
 
+    /* result == first operand */
+    TEST_ASSERT( mbedtls_mpi_sub_mpi( &X, &X, &Y ) == 0 );
+    TEST_ASSERT( mbedtls_mpi_cmp_mpi( &X, &A ) == 0 );
+    TEST_ASSERT( mbedtls_mpi_read_string( &X, radix_X, input_X ) == 0 );
+
+    /* result == second operand */
+    TEST_ASSERT( mbedtls_mpi_sub_mpi( &Y, &X, &Y ) == 0 );
+    TEST_ASSERT( mbedtls_mpi_cmp_mpi( &Y, &A ) == 0 );
+
 exit:
     mbedtls_mpi_free( &X ); mbedtls_mpi_free( &Y ); mbedtls_mpi_free( &Z ); mbedtls_mpi_free( &A );
 }
@@ -968,6 +959,17 @@ void mbedtls_mpi_sub_abs( int radix_X, char * input_X, int radix_Y,
     if( res == 0 )
         TEST_ASSERT( mbedtls_mpi_cmp_mpi( &Z, &A ) == 0 );
 
+    /* result == first operand */
+    TEST_ASSERT( mbedtls_mpi_sub_abs( &X, &X, &Y ) == sub_result );
+    if( sub_result == 0 )
+        TEST_ASSERT( mbedtls_mpi_cmp_mpi( &X, &A ) == 0 );
+    TEST_ASSERT( mbedtls_mpi_read_string( &X, radix_X, input_X ) == 0 );
+
+    /* result == second operand */
+    TEST_ASSERT( mbedtls_mpi_sub_abs( &Y, &X, &Y ) == sub_result );
+    if( sub_result == 0 )
+        TEST_ASSERT( mbedtls_mpi_cmp_mpi( &Y, &A ) == 0 );
+
 exit:
     mbedtls_mpi_free( &X ); mbedtls_mpi_free( &Y ); mbedtls_mpi_free( &Z ); mbedtls_mpi_free( &A );
 }