indexing was broken, and was creating a memory corruption segfault. F…

…ixed indexing, cleaned up some code, etc. Should all work now

src/pmc/nummatrix2d.pmc

@@ -12,30 +12,32 @@ static void
 resize_matrix(PARROT_INTERP, PMC * self, INTVAL x, INTVAL y)
 {
     Parrot_NumMatrix2D_attributes * const attrs = PARROT_NUMMATRIX2D(self);
+    /* Store the old values */
     const INTVAL old_x = attrs->x;
     const INTVAL old_y = attrs->y;
+    FLOATVAL * old_s = attrs->storage;
+
+    /* x and y are indices, not sizes. Resize the matrix to accomodate this
+       new point without shrinking by taking the max. */
     const INTVAL new_x = INDEX_MAX(old_x, x + 1);
     const INTVAL new_y = INDEX_MAX(old_y, y + 1);
     const INTVAL newsize = new_x * new_y;
     FLOATVAL * new_s = (FLOATVAL *)mem_sys_allocate_zeroed(newsize * sizeof (FLOATVAL));
-    FLOATVAL * old_s = attrs->storage;
-    const INTVAL min_x = INDEX_MIN(old_x, new_x);
-    const INTVAL min_y = INDEX_MIN(old_y, new_y);
+
     INTVAL i, j;
-    for (i = 0; i < min_x; i++) {
-        for (j = 0; j < min_y; j++) {
+    for (i = 0; i < old_x; i++) {
+        for (j = 0; j < old_y; j++) {
             ITEM_XY_ROWMAJOR(new_s, new_x, new_y, i, j) =
                 ITEM_XY_ROWMAJOR(old_s, old_x, old_y, i, j);
         }
     }
     attrs->storage = new_s;
     attrs->x = new_x;
     attrs->y = new_y;
-    mem_sys_free(old_s);
+    if (old_s)
+        mem_sys_free(old_s);
 }
 
-
-
 pmclass NumMatrix2D dynpmc auto_attrs {
     ATTR FLOATVAL * storage;
     ATTR INTVAL x;
@@ -55,6 +57,12 @@ pmclass NumMatrix2D dynpmc auto_attrs {
 */
 
     VTABLE void init() {
+        Parrot_NumMatrix2D_attributes * attr =
+            (Parrot_NumMatrix2D_attributes *) PARROT_NUMMATRIX2D(SELF);
+        attr->storage = NULL;
+        attr->x = 0;
+        attr->y = 0;
+        attr->flags = 0;
         PObj_custom_destroy_SET(SELF);
     }
 

src/pmc/pla_matrix_types.h

@@ -11,16 +11,16 @@ do { \
 } while(0);
 
 #define INDEX_XY_ROWMAJOR(x_max, y_max, x, y) \
-    (((x_max) * (x)) + (y))
+    (((y_max) * (x)) + (y))
 
 #define INDEX_XY_COLMAJOR(x_max, y_max, x, y) \
-    (((y_max) * (y)) + (x))
+    (((x_max) * (y)) + (x))
 
 #define ITEM_XY_ROWMAJOR(s, x_max, y_max, x, y) \
-    (s)[((x_max) * (x)) + (y)]
+    (s)[((y_max) * (x)) + (y)]
 
 #define ITEM_XY_COLMAJOR(s, x_max, y_max, x, y) \
-    (s)[((y_max) * (y)) + (x)]
+    (s)[((x_max) * (y)) + (x)]
 
 #define INDEX_MIN(a, b) (((a) <= (b))?(a):(b))
 #define INDEX_MAX(a, b) (((a) >= (b))?(a):(b))

t/10-nummatrix.t

@@ -23,7 +23,7 @@ sub MAIN () {
     create_nummatrix2d();
     vtable_set_number_keyed();
     vtable_get_number_keyed();
-    vtable_get_attr_keyed_str();
+    vtable_get_attr_str();
     vtable_get_integer_keyed();
     vtable_set_integer_keyed();
     vtable_get_string();
@@ -46,7 +46,6 @@ sub MAIN () {
     method_mem_transpose();
     method_iterate_function_inplace();
 }
-
 sub create_nummatrix2d() {
     Q:PIR {
         $P0 = new 'NumMatrix2D'
@@ -107,7 +106,7 @@ sub vtable_get_number_keyed() {
     }
 }
 
-sub vtable_get_attr_keyed_str() {
+sub vtable_get_attr_str() {
     Q:PIR {
         $P0 = new 'NumMatrix2D'
         $P0[2;5] = 1.0