extmod/moductypes: Fix size and offset calculation for ARRAY of FLOAT32.

uctypes.FLOAT32 has a special value representation and
uctypes_struct_scalar_size() should be used instead of GET_SCALAR_SIZE().

Signed-off-by: Damien George <damien@micropython.org>

extmod/moductypes.c

@@ -164,7 +164,7 @@ STATIC mp_uint_t uctypes_struct_agg_size(mp_obj_tuple_t *t, int layout_type, mp_
             mp_uint_t item_s;
             if (t->len == 2) {
                 // Elements of array are scalar
-                item_s = GET_SCALAR_SIZE(val_type);
+                item_s = uctypes_struct_scalar_size(val_type);
                 if (item_s > *max_field_size) {
                     *max_field_size = item_s;
                 }
@@ -541,7 +541,7 @@ STATIC mp_obj_t uctypes_struct_subscr(mp_obj_t self_in, mp_obj_t index_in, mp_ob
                         return value; // just !MP_OBJ_NULL
                     }
                 } else {
-                    byte *p = self->addr + GET_SCALAR_SIZE(val_type) * index;
+                    byte *p = self->addr + uctypes_struct_scalar_size(val_type) * index;
                     if (value == MP_OBJ_SENTINEL) {
                         return get_unaligned(val_type, p, self->flags);
                     } else {

tests/extmod/uctypes_le_float.py

@@ -22,3 +22,19 @@ print("%.4f" % S.f64)
 
 S.uf64 = 12.34
 print("%.4f" % S.uf64)
+
+# array of float/double
+desc = {
+    "af32": (uctypes.ARRAY | 0, uctypes.FLOAT32 | 2),
+    "af64": (uctypes.ARRAY | 0, uctypes.FLOAT64 | 2),
+}
+data = bytearray(16)
+S = uctypes.struct(uctypes.addressof(data), desc, uctypes.LITTLE_ENDIAN)
+
+S.af32[0] = 1
+S.af32[1] = 2
+print("%.4f %.4f" % (S.af32[0], S.af32[1]), data)
+
+S.af64[0] = 1
+S.af64[1] = 2
+print("%.4f %.4f" % (S.af64[0], S.af64[1]), data)

tests/extmod/uctypes_le_float.py.exp

@@ -1,3 +1,5 @@
 12.3400
 12.3400
 12.3400
+1.0000 2.0000 bytearray(b'\x00\x00\x80?\x00\x00\x00@\x00\x00\x00\x00\x00\x00\x00\x00')
+1.0000 2.0000 bytearray(b'\x00\x00\x00\x00\x00\x00\xf0?\x00\x00\x00\x00\x00\x00\x00@')

tests/extmod/uctypes_sizeof_float.py

@@ -6,3 +6,5 @@ except ImportError:
 
 print(uctypes.sizeof({"f": uctypes.FLOAT32}))
 print(uctypes.sizeof({"f": uctypes.FLOAT64}))
+print(uctypes.sizeof({"f": (uctypes.ARRAY | 0, uctypes.FLOAT32 | 2)}))
+print(uctypes.sizeof({"f": (uctypes.ARRAY | 0, uctypes.FLOAT64 | 2)}))

tests/extmod/uctypes_sizeof_float.py.exp

@@ -1,2 +1,4 @@
 4
 8
+8
+16