py: Big improvements to inline assembler.

Improved the Thumb assembler back end.  Added many more Thumb
instructions to the inline assembler.  Improved parsing of assembler
instructions and arguments.  Assembler functions can now be passed the
address of any object that supports the buffer protocol (to get the
address of the buffer).  Added an example of how to sum numbers from
an array in assembler.

1 files changed, 27 insertions, 18 deletions

diff --git a/py/objfun.c b/py/objfun.c
index dd4b7347c..4ef92c025 100644
--- a/py/objfun.c
+++ b/py/objfun.c
@@ -422,26 +422,35 @@ STATIC machine_uint_t convert_obj_for_inline_asm(mp_obj_t obj) {
         // pointer to the string (it's probably constant though!)
         uint l;
         return (machine_uint_t)mp_obj_str_get_data(obj, &l);
+    } else {
+        mp_obj_type_t *type = mp_obj_get_type(obj);
+        if (0) {
 #if MICROPY_ENABLE_FLOAT
-    } else if (MP_OBJ_IS_TYPE(obj, &mp_type_float)) {
-        // convert float to int (could also pass in float registers)
-        return (machine_int_t)mp_obj_float_get(obj);
+        } else if (type == &mp_type_float) {
+            // convert float to int (could also pass in float registers)
+            return (machine_int_t)mp_obj_float_get(obj);
 #endif
-    } else if (MP_OBJ_IS_TYPE(obj, &mp_type_tuple)) {
-        // pointer to start of tuple (could pass length, but then could use len(x) for that)
-        uint len;
-        mp_obj_t *items;
-        mp_obj_tuple_get(obj, &len, &items);
-        return (machine_uint_t)items;
-    } else if (MP_OBJ_IS_TYPE(obj, &mp_type_list)) {
-        // pointer to start of list (could pass length, but then could use len(x) for that)
-        uint len;
-        mp_obj_t *items;
-        mp_obj_list_get(obj, &len, &items);
-        return (machine_uint_t)items;
-    } else {
-        // just pass along a pointer to the object
-        return (machine_uint_t)obj;
+        } else if (type == &mp_type_tuple) {
+            // pointer to start of tuple (could pass length, but then could use len(x) for that)
+            uint len;
+            mp_obj_t *items;
+            mp_obj_tuple_get(obj, &len, &items);
+            return (machine_uint_t)items;
+        } else if (type == &mp_type_list) {
+            // pointer to start of list (could pass length, but then could use len(x) for that)
+            uint len;
+            mp_obj_t *items;
+            mp_obj_list_get(obj, &len, &items);
+            return (machine_uint_t)items;
+        } else if (type->buffer_p.get_buffer != NULL) {
+            // supports the buffer protocol, get a pointer to the data
+            buffer_info_t bufinfo;
+            type->buffer_p.get_buffer(obj, &bufinfo, BUFFER_READ);
+            return (machine_uint_t)bufinfo.buf;
+        } else {
+            // just pass along a pointer to the object
+            return (machine_uint_t)obj;
+        }
     }
 }