tests/micropython: Make tests behave in low memory condition.

This commit changes the "viper_ptr*_store_boundary" tests to make them
fail more gracefully in low memory conditions.

The original version of the tests compiled viper code blocks on the fly
when it needed them, making them fail at runtime on some boards that do
not come with enough memory for this test.  This clashes with
"run-tests.py"'s ability to look for a particular signature to mark
tests as skipped due to not enough memory.

Now compiled code blocks are generated at the beginning of the test
inside an appropriate exception handler.  In case of a memory error when
pre-compiling a code block, the running test exits reporting a low
memory condition to the test runner.  This allows to have clean test
runs on all platforms when it comes to viper pointer tests.

Signed-off-by: Alessandro Gatti <a.gatti@frob.it>

tests/micropython/viper_ptr16_store_boundary.py

@@ -6,15 +6,12 @@ def set{off}(dest: ptr16):
     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 = 2
 MASK = (1 << (8 * SIZE)) - 1
 
-
 next_int = 1
 test_buffer = bytearray(SIZE)
 
@@ -32,6 +29,10 @@ def next_value() -> uint:
     return output & MASK
 
 
+def get_index(src, i):
+    return src[i * SIZE] + (src[(i * SIZE) + 1] << 8)
+
+
 @micropython.viper
 def set_index(dest: ptr16, i: int, val: uint):
     saved = dest
@@ -39,22 +40,24 @@ def set_index(dest: ptr16, i: int, val: uint):
     assert int(saved) == int(dest)
 
 
-def get_index(src, i):
-    return src[i * SIZE] + (src[(i * SIZE) + 1] << 8)
+try:
+    buffer = bytearray((((1 << max(BIT_THRESHOLDS)) // 1024) + 1) * 1024)
+
+    for bit in BIT_THRESHOLDS:
+        offset = (1 << bit) - (2 * SIZE)
+        for index in range(0, 3 * SIZE, SIZE):
+            exec(SET_TEMPLATE.format(off=(offset + index) // SIZE, val=next_value()))
+except MemoryError:
+    print("SKIP-TOO-LARGE")
+    raise SystemExit
 
 
-buffer = bytearray(((1 << max(BIT_THRESHOLDS) + 1) // 1024) * 1024)
 for bit in BIT_THRESHOLDS:
     print("---", bit)
-    pre, idx, post = (
-        (((1 << bit) - (2 * SIZE)) // SIZE),
-        (((1 << bit) - (1 * SIZE)) // SIZE),
-        ((1 << bit) // SIZE),
-    )
-    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()))
+    offset = (1 << bit) - (2 * SIZE)
+    for index in range(0, 3 * SIZE, SIZE):
+        globals()["set{}".format((offset + index) // SIZE)](buffer)
+        print(hex(get_index(buffer, (offset + index) // SIZE)))
+    for index in range(0, 3 * SIZE, SIZE):
+        set_index(buffer, (offset + index) // SIZE, next_value())
+        print(hex(get_index(buffer, (offset + index) // SIZE)))

tests/micropython/viper_ptr16_store_boundary.py.exp

@@ -1,20 +1,28 @@
 --- 5
-0x1 0x102 0x203
+0x1
+0x102
+0x203
+0xc0d
+0xd0e
+0xe0f
+--- 8
 0x304
 0x405
 0x506
---- 8
-0x607 0x708 0x809
-0x90a
-0xa0b
-0xb0c
---- 11
-0xc0d 0xd0e 0xe0f
 0xf10
 0x1011
 0x1112
+--- 11
+0x607
+0x708
+0x809
+0x1213
+0x1314
+0x1415
 --- 12
-0x1213 0x1314 0x1415
+0x90a
+0xa0b
+0xb0c
 0x1516
 0x1617
 0x1718

tests/micropython/viper_ptr32_store_boundary.py

@@ -6,8 +6,6 @@ def set{off}(dest: ptr32):
     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)
@@ -31,13 +29,6 @@ def next_value() -> uint:
     return output & MASK
 
 
-@micropython.viper
-def set_index(dest: ptr32, i: int, val: uint):
-    saved = dest
-    dest[i] = val
-    assert int(saved) == int(dest)
-
-
 def get_index(src, i):
     return (
         src[i * SIZE]
@@ -47,18 +38,31 @@ def get_index(src, i):
     )
 
 
-buffer = bytearray(((1 << max(BIT_THRESHOLDS) + 1) // 1024) * 1024)
+@micropython.viper
+def set_index(dest: ptr32, i: int, val: uint):
+    saved = dest
+    dest[i] = val
+    assert int(dest) == int(saved)
+
+
+try:
+    buffer = bytearray((((1 << max(BIT_THRESHOLDS)) // 1024) + 1) * 1024)
+
+    for bit in BIT_THRESHOLDS:
+        offset = (1 << bit) - (2 * SIZE)
+        for index in range(0, 3 * SIZE, SIZE):
+            exec(SET_TEMPLATE.format(off=(offset + index) // SIZE, val=next_value()))
+except MemoryError:
+    print("SKIP-TOO-LARGE")
+    raise SystemExit
+
+
 for bit in BIT_THRESHOLDS:
     print("---", bit)
-    pre, idx, post = (
-        (((1 << bit) - (2 * SIZE)) // SIZE),
-        (((1 << bit) - (1 * SIZE)) // SIZE),
-        ((1 << bit) // SIZE),
-    )
-    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()))
+    offset = (1 << bit) - (2 * SIZE)
+    for index in range(0, 3 * SIZE, SIZE):
+        globals()["set{}".format((offset + index) // SIZE)](buffer)
+        print(hex(get_index(buffer, (offset + index) // SIZE)))
+    for index in range(0, 3 * SIZE, SIZE):
+        set_index(buffer, (offset + index) // SIZE, next_value())
+        print(hex(get_index(buffer, (offset + index) // SIZE)))

tests/micropython/viper_ptr32_store_boundary.py.exp

@@ -1,20 +1,28 @@
 --- 5
-0x1 0x102 0x10203
+0x1
+0x102
+0x10203
+0xa0b0c0d
+0xb0c0d0e
+0xc0d0e0f
+--- 8
 0x1020304
 0x2030405
 0x3040506
---- 8
-0x4050607 0x5060708 0x6070809
-0x708090a
-0x8090a0b
-0x90a0b0c
---- 11
-0xa0b0c0d 0xb0c0d0e 0xc0d0e0f
 0xd0e0f10
 0xe0f1011
 0xf101112
+--- 11
+0x4050607
+0x5060708
+0x6070809
+0x10111213
+0x11121314
+0x12131415
 --- 12
-0x10111213 0x11121314 0x12131415
+0x708090a
+0x8090a0b
+0x90a0b0c
 0x13141516
 0x14151617
 0x15161718

tests/micropython/viper_ptr8_store_boundary.py

@@ -6,8 +6,6 @@ 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)
@@ -31,6 +29,10 @@ def next_value() -> uint:
     return output & MASK
 
 
+def get_index(src: ptr8, i: int):
+    return src[i]
+
+
 @micropython.viper
 def set_index(dest: ptr8, i: int, val: uint):
     saved = dest
@@ -38,18 +40,24 @@ def set_index(dest: ptr8, i: int, val: uint):
     assert int(dest) == int(saved)
 
 
-def get_index(src: ptr8, i: int):
-    return src[i]
+try:
+    buffer = bytearray((((1 << max(BIT_THRESHOLDS)) // 1024) + 1) * 1024)
+
+    for bit in BIT_THRESHOLDS:
+        offset = (1 << bit) - (2 * SIZE)
+        for index in range(0, 3 * SIZE, SIZE):
+            exec(SET_TEMPLATE.format(off=(offset + index) // SIZE, val=next_value()))
+except MemoryError:
+    print("SKIP-TOO-LARGE")
+    raise SystemExit
 
 
-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()))
+    offset = (1 << bit) - (2 * SIZE)
+    for index in range(0, 3 * SIZE, SIZE):
+        globals()["set{}".format((offset + index) // SIZE)](buffer)
+        print(hex(get_index(buffer, (offset + index) // SIZE)))
+    for index in range(0, 3 * SIZE, SIZE):
+        set_index(buffer, (offset + index) // SIZE, next_value())
+        print(hex(get_index(buffer, (offset + index) // SIZE)))

tests/micropython/viper_ptr8_store_boundary.py.exp

@@ -1,20 +1,28 @@
 --- 5
-0x1 0x2 0x3
+0x1
+0x2
+0x3
+0xd
+0xe
+0xf
+--- 8
 0x4
 0x5
 0x6
---- 8
-0x7 0x8 0x9
-0xa
-0xb
-0xc
---- 11
-0xd 0xe 0xf
 0x10
 0x11
 0x12
+--- 11
+0x7
+0x8
+0x9
+0x13
+0x14
+0x15
 --- 12
-0x13 0x14 0x15
+0xa
+0xb
+0xc
 0x16
 0x17
 0x18