tests/micropython/viper_ptr: Add tests for arch edge cases.

This commit adds a series of test cases to exercise the Viper code
generator load/store emitting capabilities on certain boundary
conditions.

The new test cases check whether the emitted load/store code performs
correctly when dealing with specific memory offsets, which trigger
specific code generation sequences on different architectures.

Right now the cases are for unsigned offsets whose bitmasks span up to
5, 8, and 12 bits (respectively Arm/Thumb, Xtensa, RV32).

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

tests/micropython/viper_ptr16_load_boundary.py

@@ -0,0 +1,25 @@
+# Test boundary conditions for various architectures
+
+GET_TEMPLATE = """
+@micropython.viper
+def get{off}(src: ptr16) -> int:
+    return src[{off}]
+print(b[{off} * 2:({off} + 1) * 2])
+"""
+
+
+@micropython.viper
+def get_index(src: ptr16, i: int) -> int:
+    return src[i]
+
+
+b = bytearray(5000)
+b[28:38] = b"0123456789"
+b[252:262] = b"ABCDEFGHIJ"
+b[4092:4102] = b"KLMNOPQRST"
+
+for pre, idx, post in (15, 16, 17), (127, 128, 129), (2047, 2048, 2049):
+    print(get_index(b, pre), get_index(b, idx), get_index(b, post))
+    exec(GET_TEMPLATE.format(off=pre))
+    exec(GET_TEMPLATE.format(off=idx))
+    exec(GET_TEMPLATE.format(off=post))

tests/micropython/viper_ptr16_load_boundary.py.exp

@@ -0,0 +1,12 @@
+13106 13620 14134
+bytearray(b'23')
+bytearray(b'45')
+bytearray(b'67')
+17475 17989 18503
+bytearray(b'CD')
+bytearray(b'EF')
+bytearray(b'GH')
+20045 20559 21073
+bytearray(b'MN')
+bytearray(b'OP')
+bytearray(b'QR')

tests/micropython/viper_ptr16_store_boundary.py

@@ -0,0 +1,41 @@
+# Test boundary conditions for various architectures
+
+SET_TEMPLATE = """
+@micropython.viper
+def set{off}(dest: ptr16):
+    dest[{off}] = {val}
+set{off}(b)
+print(b[{off} * 2:({off} + 1) * 2])
+"""
+
+TEST_DATA = (
+    (15, (0x4241, 0x4443, 0x4645)),
+    (127, (0x4847, 0x4A49, 0x4C4B)),
+    (2047, (0x4E4D, 0x504F, 0x5251)),
+)
+
+
+@micropython.viper
+def set_index(dest: ptr16, i: int, val: int):
+    dest[i] = val
+
+
+@micropython.viper
+def set_index(dest: ptr16, i: int, val: int):
+    dest[i] = val
+
+
+b = bytearray(5000)
+for start, vals in TEST_DATA:
+    for i, v in enumerate(vals):
+        set_index(b, start + i, v)
+        print(b[(start + i) * 2 : (start + i + 1) * 2])
+
+
+for i in range(len(b)):
+    b[i] = 0
+
+
+for start, vals in TEST_DATA:
+    for i, v in enumerate(vals):
+        exec(SET_TEMPLATE.format(off=start + i, val=v + 0x0101))

tests/micropython/viper_ptr16_store_boundary.py.exp

@@ -0,0 +1,18 @@
+bytearray(b'AB')
+bytearray(b'CD')
+bytearray(b'EF')
+bytearray(b'GH')
+bytearray(b'IJ')
+bytearray(b'KL')
+bytearray(b'MN')
+bytearray(b'OP')
+bytearray(b'QR')
+bytearray(b'BC')
+bytearray(b'DE')
+bytearray(b'FG')
+bytearray(b'HI')
+bytearray(b'JK')
+bytearray(b'LM')
+bytearray(b'NO')
+bytearray(b'PQ')
+bytearray(b'RS')

tests/micropython/viper_ptr32_load_boundary.py

@@ -0,0 +1,25 @@
+# Test boundary conditions for various architectures
+
+GET_TEMPLATE = """
+@micropython.viper
+def get{off}(src: ptr32) -> int:
+    return src[{off}]
+print(b[{off} * 4:({off} + 1) * 4])
+"""
+
+
+@micropython.viper
+def get_index(src: ptr32, i: int) -> int:
+    return src[i]
+
+
+b = bytearray(5000)
+b[24:43] = b"0123456789ABCDEFGHIJ"
+b[248:268] = b"KLMNOPQRSTUVWXYZabcd"
+b[4088:4108] = b"efghijklmnopqrstuvwx"
+
+for pre, idx, post in (7, 8, 9), (63, 64, 65), (1023, 1024, 1025):
+    print(get_index(b, pre), get_index(b, idx), get_index(b, post))
+    exec(GET_TEMPLATE.format(off=pre))
+    exec(GET_TEMPLATE.format(off=idx))
+    exec(GET_TEMPLATE.format(off=post))

tests/micropython/viper_ptr32_load_boundary.py.exp

@@ -0,0 +1,12 @@
+926299444 1111570744 1178944579
+bytearray(b'4567')
+bytearray(b'89AB')
+bytearray(b'CDEF')
+1381060687 1448432723 1515804759
+bytearray(b'OPQR')
+bytearray(b'STUV')
+bytearray(b'WXYZ')
+1818978921 1886350957 1953722993
+bytearray(b'ijkl')
+bytearray(b'mnop')
+bytearray(b'qrst')

tests/micropython/viper_ptr32_store_boundary.py

@@ -0,0 +1,35 @@
+# Test boundary conditions for various architectures
+
+TEST_DATA = (
+    (3, (0x04030201, 0x08070605, 0x0C0B0A09)),
+    (63, (0x100F0E0D, 0x14131211, 0x18171615)),
+    (1023, (0x1C1B1A19, 0x201F1E1D, 0x24232221)),
+)
+
+SET_TEMPLATE = """
+@micropython.viper
+def set{off}(dest: ptr32):
+    dest[{off}] = {val} & 0x3FFFFFFF
+set{off}(b)
+print(b[{off} * 4:({off} + 1) * 4])
+"""
+
+
+@micropython.viper
+def set_index(dest: ptr32, i: int, val: int):
+    dest[i] = val
+
+
+b = bytearray(5000)
+for start, vals in TEST_DATA:
+    for i, v in enumerate(vals):
+        set_index(b, start + i, v)
+        print(b[(start + i) * 4 : (start + i + 1) * 4])
+
+for i in range(len(b)):
+    b[i] = 0
+
+
+for start, vals in TEST_DATA:
+    for i, v in enumerate(vals):
+        exec(SET_TEMPLATE.format(off=start + i, val=v + 0x01010101))

tests/micropython/viper_ptr32_store_boundary.py.exp

@@ -0,0 +1,18 @@
+bytearray(b'\x01\x02\x03\x04')
+bytearray(b'\x05\x06\x07\x08')
+bytearray(b'\t\n\x0b\x0c')
+bytearray(b'\r\x0e\x0f\x10')
+bytearray(b'\x11\x12\x13\x14')
+bytearray(b'\x15\x16\x17\x18')
+bytearray(b'\x19\x1a\x1b\x1c')
+bytearray(b'\x1d\x1e\x1f ')
+bytearray(b'!"#$')
+bytearray(b'\x02\x03\x04\x05')
+bytearray(b'\x06\x07\x08\t')
+bytearray(b'\n\x0b\x0c\r')
+bytearray(b'\x0e\x0f\x10\x11')
+bytearray(b'\x12\x13\x14\x15')
+bytearray(b'\x16\x17\x18\x19')
+bytearray(b'\x1a\x1b\x1c\x1d')
+bytearray(b'\x1e\x1f !')
+bytearray(b'"#$%')

tests/micropython/viper_ptr8_load_boundary.py

@@ -0,0 +1,25 @@
+# Test boundary conditions for various architectures
+
+GET_TEMPLATE = """
+@micropython.viper
+def get{off}(src: ptr8) -> int:
+    return src[{off}]
+print(get{off}(b))
+"""
+
+
+@micropython.viper
+def get_index(src: ptr8, i: int) -> int:
+    return src[i]
+
+
+b = bytearray(5000)
+b[30:32] = b"123"
+b[254:256] = b"456"
+b[4094:4096] = b"789"
+
+for pre, idx, post in (30, 31, 32), (254, 255, 256), (4094, 4095, 4096):
+    print(get_index(b, pre), get_index(b, idx), get_index(b, post))
+    exec(GET_TEMPLATE.format(off=pre))
+    exec(GET_TEMPLATE.format(off=idx))
+    exec(GET_TEMPLATE.format(off=post))

tests/micropython/viper_ptr8_load_boundary.py.exp

@@ -0,0 +1,12 @@
+49 50 51
+49
+50
+51
+52 53 54
+52
+53
+54
+55 56 57
+55
+56
+57

tests/micropython/viper_ptr8_store_boundary.py

@@ -0,0 +1,30 @@
+# Test boundary conditions for various architectures
+
+TEST_DATA = ((49, 30, 3), (52, 254, 3), (55, 4094, 3))
+
+SET_TEMPLATE = """
+@micropython.viper
+def set{off}(dest: ptr8):
+    dest[{off}] = {val}
+set{off}(b)
+print(b[{off}])
+"""
+
+
+@micropython.viper
+def set_index(dest: ptr8, i: int, val: int):
+    dest[i] = val
+
+
+b = bytearray(5000)
+for val, start, count in TEST_DATA:
+    for i in range(count):
+        set_index(b, start + i, val + i)
+    print(b[start : start + count])
+
+for i in range(len(b)):
+    b[i] = 0
+
+for val, start, count in TEST_DATA:
+    for i in range(count):
+        exec(SET_TEMPLATE.format(off=start + i, val=val + i + 16))

tests/micropython/viper_ptr8_store_boundary.py.exp

@@ -0,0 +1,12 @@
+bytearray(b'123')
+bytearray(b'456')
+bytearray(b'789')
+65
+66
+67
+68
+69
+70
+71
+72
+73