1 files changed, 55 insertions, 0 deletions
diff --git a/tests/micropython/viper_ptr8_store_boundary.py b/tests/micropython/viper_ptr8_store_boundary.py
new file mode 100644
index 000000000..d3cba17e1
--- /dev/null
+++ b/tests/micropython/viper_ptr8_store_boundary.py
@@ -0,0 +1,55 @@
+# Test boundary conditions for various architectures
+
+SET_TEMPLATE = """
+@micropython.viper
+def set{off}(dest: ptr8):
+    saved = dest
+    dest[{off}] = {val}
+    assert int(saved) == int(dest)
+set{off}(buffer)
+print(hex(get_index(buffer, {off})))
+"""
+
+BIT_THRESHOLDS = (5, 8, 11, 12)
+SIZE = 1
+MASK = (1 << (8 * SIZE)) - 1
+
+next_int = 1
+test_buffer = bytearray(SIZE)
+
+
+def next_value() -> uint:
+    global next_int
+    global test_buffer
+    for index in range(1, SIZE):
+        test_buffer[index - 1] = test_buffer[index]
+    test_buffer[SIZE - 1] = next_int
+    next_int += 1
+    output = 0
+    for byte in test_buffer:
+        output = (output << 8) | byte
+    return output & MASK
+
+
+@micropython.viper
+def set_index(dest: ptr8, i: int, val: uint):
+    saved = dest
+    dest[i] = val
+    assert int(dest) == int(saved)
+
+
+def get_index(src: ptr8, i: int):
+    return src[i]
+
+
+buffer = bytearray(((1 << max(BIT_THRESHOLDS) + 1) // 1024) * 1024)
+for bit in BIT_THRESHOLDS:
+    print("---", bit)
+    pre, idx, post = (((1 << bit) - (2 * SIZE)), ((1 << bit) - (1 * SIZE)), (1 << bit))
+    set_index(buffer, pre, next_value())
+    set_index(buffer, idx, next_value())
+    set_index(buffer, post, next_value())
+    print(hex(get_index(buffer, pre)), hex(get_index(buffer, idx)), hex(get_index(buffer, post)))
+    exec(SET_TEMPLATE.format(off=pre, val=next_value()))
+    exec(SET_TEMPLATE.format(off=idx, val=next_value()))
+    exec(SET_TEMPLATE.format(off=post, val=next_value()))