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FA-52386 / Raster memory layout / Open access

Bitplane Word Storage: Final bitplane word validity mask marks low bits or padding as pixels · case 01

The returned physical layout descriptor disagrees with the declared buffer mapping at last_word_mask.

Verified by executionVariant 1 · 6 checks per implementationDownload source bundle ↓JSON ↗

ROOT CAUSE

Final bitplane word validity mask marks low bits or padding as pixels The faulty expression is (1<<(p["w"]%16))-1.

THE FAILURE

Final bitplane word validity mask marks low bits or padding as pixels The faulty expression is (1<<(p["w"]%16))-1.

Unsuccessful approach: The attempted repair uses 65535 and still violates the layout contract.

Case contract

A four-plane bitmap uses sixteen-bit words, most-significant-bit-first pixels, independent plane headers, and plane-major storage. Each row contains an extra sentinel word. Return word location and update mask without decoding colors. Return the named intermediate layout descriptor and final address fields; all quantities are integer byte offsets unless explicitly stated.

Why this case matters

Offline raster resource, upload, readback, and storage-layout regression model.

1 / The failure

Exit 1
"""Failure Map reference implementation. Python standard library only."""
import json

N = 1
observations = []
def solve(p):
    p = dict(p)
    words = (p["w"]+15)//16
    row_words = words+1
    row_bytes = row_words*2
    plane_bytes = p["h"]*row_bytes+4
    plane_origin = p["base"]+p["plane"]*plane_bytes+4
    word_column = p["x"]//16
    bit_index = 15-p["x"]%16
    mask = 1<<bit_index
    address = plane_origin+p["y"]*row_bytes+word_column*2
    last_word_mask = (1<<(p["w"]%16))-1
    return {'words': words, 'row_words': row_words, 'row_bytes': row_bytes, 'plane_bytes': plane_bytes, 'plane_origin': plane_origin, 'word_column': word_column, 'bit_index': bit_index, 'mask': mask, 'address': address, 'last_word_mask': last_word_mask}
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
cases = {1: [({'w': 18, 'h': 2, 'x': 0, 'y': 0, 'plane': 0, 'base': 11}, {'words': 2, 'row_words': 3, 'row_bytes': 6, 'plane_bytes': 16, 'plane_origin': 15, 'word_column': 0, 'bit_index': 15, 'mask': 32768, 'address': 15, 'last_word_mask': 49152}), ({'w': 19, 'h': 3, 'x': 1, 'y': 1, 'plane': 1, 'base': 11}, {'words': 2, 'row_words': 3, 'row_bytes': 6, 'plane_bytes': 22, 'plane_origin': 37, 'word_column': 0, 'bit_index': 14, 'mask': 16384, 'address': 43, 'last_word_mask': 57344}), ({'w': 20, 'h': 4, 'x': 15, 'y': 2, 'plane': 2, 'base': 11}, {'words': 2, 'row_words': 3, 'row_bytes': 6, 'plane_bytes': 28, 'plane_origin': 71, 'word_column': 0, 'bit_index': 0, 'mask': 1, 'address': 83, 'last_word_mask': 61440}), ({'w': 21, 'h': 5, 'x': 16, 'y': 3, 'plane': 3, 'base': 11}, {'words': 2, 'row_words': 3, 'row_bytes': 6, 'plane_bytes': 34, 'plane_origin': 117, 'word_column': 1, 'bit_index': 15, 'mask': 32768, 'address': 137, 'last_word_mask': 63488}), ({'w': 22, 'h': 6, 'x': 17, 'y': 4, 'plane': 0, 'base': 11}, {'words': 2, 'row_words': 3, 'row_bytes': 6, 'plane_bytes': 40, 'plane_origin': 15, 'word_column': 1, 'bit_index': 14, 'mask': 16384, 'address': 41, 'last_word_mask': 64512}), ({'w': 23, 'h': 7, 'x': 18, 'y': 5, 'plane': 1, 'base': 11}, {'words': 2, 'row_words': 3, 'row_bytes': 6, 'plane_bytes': 46, 'plane_origin': 61, 'word_column': 1, 'bit_index': 13, 'mask': 8192, 'address': 93, 'last_word_mask': 65024})], 2: [({'w': 19, 'h': 2, 'x': 0, 'y': 0, 'plane': 0, 'base': 22}, {'words': 2, 'row_words': 3, 'row_bytes': 6, 'plane_bytes': 16, 'plane_origin': 26, 'word_column': 0, 'bit_index': 15, 'mask': 32768, 'address': 26, 'last_word_mask': 57344}), ({'w': 20, 'h': 3, 'x': 1, 'y': 1, 'plane': 1, 'base': 22}, {'words': 2, 'row_words': 3, 'row_bytes': 6, 'plane_bytes': 22, 'plane_origin': 48, 'word_column': 0, 'bit_index': 14, 'mask': 16384, 'address': 54, 'last_word_mask': 61440}), ({'w': 21, 'h': 4, 'x': 15, 'y': 2, 'plane': 2, 'base': 22}, {'words': 2, 'row_words': 3, 'row_bytes': 6, 'plane_bytes': 28, 'plane_origin': 82, 'word_column': 0, 'bit_index': 0, 'mask': 1, 'address': 94, 'last_word_mask': 63488}), ({'w': 22, 'h': 5, 'x': 16, 'y': 3, 'plane': 3, 'base': 22}, {'words': 2, 'row_words': 3, 'row_bytes': 6, 'plane_bytes': 34, 'plane_origin': 128, 'word_column': 1, 'bit_index': 15, 'mask': 32768, 'address': 148, 'last_word_mask': 64512}), ({'w': 23, 'h': 6, 'x': 17, 'y': 4, 'plane': 0, 'base': 22}, {'words': 2, 'row_words': 3, 'row_bytes': 6, 'plane_bytes': 40, 'plane_origin': 26, 'word_column': 1, 'bit_index': 14, 'mask': 16384, 'address': 52, 'last_word_mask': 65024}), ({'w': 24, 'h': 7, 'x': 18, 'y': 5, 'plane': 1, 'base': 22}, {'words': 2, 'row_words': 3, 'row_bytes': 6, 'plane_bytes': 46, 'plane_origin': 72, 'word_column': 1, 'bit_index': 13, 'mask': 8192, 'address': 104, 'last_word_mask': 65280})], 3: [({'w': 20, 'h': 2, 'x': 0, 'y': 0, 'plane': 0, 'base': 33}, {'words': 2, 'row_words': 3, 'row_bytes': 6, 'plane_bytes': 16, 'plane_origin': 37, 'word_column': 0, 'bit_index': 15, 'mask': 32768, 'address': 37, 'last_word_mask': 61440}), ({'w': 21, 'h': 3, 'x': 1, 'y': 1, 'plane': 1, 'base': 33}, {'words': 2, 'row_words': 3, 'row_bytes': 6, 'plane_bytes': 22, 'plane_origin': 59, 'word_column': 0, 'bit_index': 14, 'mask': 16384, 'address': 65, 'last_word_mask': 63488}), ({'w': 22, 'h': 4, 'x': 15, 'y': 2, 'plane': 2, 'base': 33}, {'words': 2, 'row_words': 3, 'row_bytes': 6, 'plane_bytes': 28, 'plane_origin': 93, 'word_column': 0, 'bit_index': 0, 'mask': 1, 'address': 105, 'last_word_mask': 64512}), ({'w': 23, 'h': 5, 'x': 16, 'y': 3, 'plane': 3, 'base': 33}, {'words': 2, 'row_words': 3, 'row_bytes': 6, 'plane_bytes': 34, 'plane_origin': 139, 'word_column': 1, 'bit_index': 15, 'mask': 32768, 'address': 159, 'last_word_mask': 65024}), ({'w': 24, 'h': 6, 'x': 17, 'y': 4, 'plane': 0, 'base': 33}, {'words': 2, 'row_words': 3, 'row_bytes': 6, 'plane_bytes': 40, 'plane_origin': 37, 'word_column': 1, 'bit_index': 14, 'mask': 16384, 'address': 63, 'last_word_mask': 65280}), ({'w': 25, 'h': 7, 'x': 18, 'y': 5, 'plane': 1, 'base': 33}, {'words': 2, 'row_words': 3, 'row_bytes': 6, 'plane_bytes': 46, 'plane_origin': 83, 'word_column': 1, 'bit_index': 13, 'mask': 8192, 'address': 115, 'last_word_mask': 65408})], 4: [({'w': 21, 'h': 2, 'x': 0, 'y': 0, 'plane': 0, 'base': 44}, {'words': 2, 'row_words': 3, 'row_bytes': 6, 'plane_bytes': 16, 'plane_origin': 48, 'word_column': 0, 'bit_index': 15, 'mask': 32768, 'address': 48, 'last_word_mask': 63488}), ({'w': 22, 'h': 3, 'x': 1, 'y': 1, 'plane': 1, 'base': 44}, {'words': 2, 'row_words': 3, 'row_bytes': 6, 'plane_bytes': 22, 'plane_origin': 70, 'word_column': 0, 'bit_index': 14, 'mask': 16384, 'address': 76, 'last_word_mask': 64512}), ({'w': 23, 'h': 4, 'x': 15, 'y': 2, 'plane': 2, 'base': 44}, {'words': 2, 'row_words': 3, 'row_bytes': 6, 'plane_bytes': 28, 'plane_origin': 104, 'word_column': 0, 'bit_index': 0, 'mask': 1, 'address': 116, 'last_word_mask': 65024}), ({'w': 24, 'h': 5, 'x': 16, 'y': 3, 'plane': 3, 'base': 44}, {'words': 2, 'row_words': 3, 'row_bytes': 6, 'plane_bytes': 34, 'plane_origin': 150, 'word_column': 1, 'bit_index': 15, 'mask': 32768, 'address': 170, 'last_word_mask': 65280}), ({'w': 25, 'h': 6, 'x': 17, 'y': 4, 'plane': 0, 'base': 44}, {'words': 2, 'row_words': 3, 'row_bytes': 6, 'plane_bytes': 40, 'plane_origin': 48, 'word_column': 1, 'bit_index': 14, 'mask': 16384, 'address': 74, 'last_word_mask': 65408}), ({'w': 26, 'h': 7, 'x': 18, 'y': 5, 'plane': 1, 'base': 44}, {'words': 2, 'row_words': 3, 'row_bytes': 6, 'plane_bytes': 46, 'plane_origin': 94, 'word_column': 1, 'bit_index': 13, 'mask': 8192, 'address': 126, 'last_word_mask': 65472})], 5: [({'w': 22, 'h': 2, 'x': 0, 'y': 0, 'plane': 0, 'base': 55}, {'words': 2, 'row_words': 3, 'row_bytes': 6, 'plane_bytes': 16, 'plane_origin': 59, 'word_column': 0, 'bit_index': 15, 'mask': 32768, 'address': 59, 'last_word_mask': 64512}), ({'w': 23, 'h': 3, 'x': 1, 'y': 1, 'plane': 1, 'base': 55}, {'words': 2, 'row_words': 3, 'row_bytes': 6, 'plane_bytes': 22, 'plane_origin': 81, 'word_column': 0, 'bit_index': 14, 'mask': 16384, 'address': 87, 'last_word_mask': 65024}), ({'w': 24, 'h': 4, 'x': 15, 'y': 2, 'plane': 2, 'base': 55}, {'words': 2, 'row_words': 3, 'row_bytes': 6, 'plane_bytes': 28, 'plane_origin': 115, 'word_column': 0, 'bit_index': 0, 'mask': 1, 'address': 127, 'last_word_mask': 65280}), ({'w': 25, 'h': 5, 'x': 16, 'y': 3, 'plane': 3, 'base': 55}, {'words': 2, 'row_words': 3, 'row_bytes': 6, 'plane_bytes': 34, 'plane_origin': 161, 'word_column': 1, 'bit_index': 15, 'mask': 32768, 'address': 181, 'last_word_mask': 65408}), ({'w': 26, 'h': 6, 'x': 17, 'y': 4, 'plane': 0, 'base': 55}, {'words': 2, 'row_words': 3, 'row_bytes': 6, 'plane_bytes': 40, 'plane_origin': 59, 'word_column': 1, 'bit_index': 14, 'mask': 16384, 'address': 85, 'last_word_mask': 65472}), ({'w': 27, 'h': 7, 'x': 18, 'y': 5, 'plane': 1, 'base': 55}, {'words': 2, 'row_words': 3, 'row_bytes': 6, 'plane_bytes': 46, 'plane_origin': 105, 'word_column': 1, 'bit_index': 13, 'mask': 8192, 'address': 137, 'last_word_mask': 65504})]}
for i, (p, expected) in enumerate(cases[N]):
    check("layout fixture " + str(i + 1), solve(p), expected)
print(json.dumps({"observations": observations, "passed": all(x["passed"] for x in observations)}, ensure_ascii=False))
raise SystemExit(0 if all(x["passed"] for x in observations) else 1)
Boundary fixtureActualExpectedOutcome
layout fixture 1{'address': 15, 'bit_index': 15, 'last_word_mask': 3, 'mask': 32768, 'plane_bytes': 16, 'plane_origin': 15, 'row_bytes': 6, 'row_words': 3, 'word_column': 0, 'words': 2}{'address': 15, 'bit_index': 15, 'last_word_mask': 49152, 'mask': 32768, 'plane_bytes': 16, 'plane_origin': 15, 'row_bytes': 6, 'row_words': 3, 'word_column': 0, 'words': 2}Failed
layout fixture 2{'address': 43, 'bit_index': 14, 'last_word_mask': 7, 'mask': 16384, 'plane_bytes': 22, 'plane_origin': 37, 'row_bytes': 6, 'row_words': 3, 'word_column': 0, 'words': 2}{'address': 43, 'bit_index': 14, 'last_word_mask': 57344, 'mask': 16384, 'plane_bytes': 22, 'plane_origin': 37, 'row_bytes': 6, 'row_words': 3, 'word_column': 0, 'words': 2}Failed
layout fixture 3{'address': 83, 'bit_index': 0, 'last_word_mask': 15, 'mask': 1, 'plane_bytes': 28, 'plane_origin': 71, 'row_bytes': 6, 'row_words': 3, 'word_column': 0, 'words': 2}{'address': 83, 'bit_index': 0, 'last_word_mask': 61440, 'mask': 1, 'plane_bytes': 28, 'plane_origin': 71, 'row_bytes': 6, 'row_words': 3, 'word_column': 0, 'words': 2}Failed
layout fixture 4{'address': 137, 'bit_index': 15, 'last_word_mask': 31, 'mask': 32768, 'plane_bytes': 34, 'plane_origin': 117, 'row_bytes': 6, 'row_words': 3, 'word_column': 1, 'words': 2}{'address': 137, 'bit_index': 15, 'last_word_mask': 63488, 'mask': 32768, 'plane_bytes': 34, 'plane_origin': 117, 'row_bytes': 6, 'row_words': 3, 'word_column': 1, 'words': 2}Failed
layout fixture 5{'address': 41, 'bit_index': 14, 'last_word_mask': 63, 'mask': 16384, 'plane_bytes': 40, 'plane_origin': 15, 'row_bytes': 6, 'row_words': 3, 'word_column': 1, 'words': 2}{'address': 41, 'bit_index': 14, 'last_word_mask': 64512, 'mask': 16384, 'plane_bytes': 40, 'plane_origin': 15, 'row_bytes': 6, 'row_words': 3, 'word_column': 1, 'words': 2}Failed
layout fixture 6{'address': 93, 'bit_index': 13, 'last_word_mask': 127, 'mask': 8192, 'plane_bytes': 46, 'plane_origin': 61, 'row_bytes': 6, 'row_words': 3, 'word_column': 1, 'words': 2}{'address': 93, 'bit_index': 13, 'last_word_mask': 65024, 'mask': 8192, 'plane_bytes': 46, 'plane_origin': 61, 'row_bytes': 6, 'row_words': 3, 'word_column': 1, 'words': 2}Failed

SHA-256 / 500b84261ccfd0fe103be7780e2d1f6bdab3909424358cb9acd9f72cd83352c2

2 / The unsuccessful fix

Exit 1
"""Failure Map reference implementation. Python standard library only."""
import json

N = 1
observations = []
def solve(p):
    p = dict(p)
    words = (p["w"]+15)//16
    row_words = words+1
    row_bytes = row_words*2
    plane_bytes = p["h"]*row_bytes+4
    plane_origin = p["base"]+p["plane"]*plane_bytes+4
    word_column = p["x"]//16
    bit_index = 15-p["x"]%16
    mask = 1<<bit_index
    address = plane_origin+p["y"]*row_bytes+word_column*2
    last_word_mask = 65535
    return {'words': words, 'row_words': row_words, 'row_bytes': row_bytes, 'plane_bytes': plane_bytes, 'plane_origin': plane_origin, 'word_column': word_column, 'bit_index': bit_index, 'mask': mask, 'address': address, 'last_word_mask': last_word_mask}
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
cases = {1: [({'w': 18, 'h': 2, 'x': 0, 'y': 0, 'plane': 0, 'base': 11}, {'words': 2, 'row_words': 3, 'row_bytes': 6, 'plane_bytes': 16, 'plane_origin': 15, 'word_column': 0, 'bit_index': 15, 'mask': 32768, 'address': 15, 'last_word_mask': 49152}), ({'w': 19, 'h': 3, 'x': 1, 'y': 1, 'plane': 1, 'base': 11}, {'words': 2, 'row_words': 3, 'row_bytes': 6, 'plane_bytes': 22, 'plane_origin': 37, 'word_column': 0, 'bit_index': 14, 'mask': 16384, 'address': 43, 'last_word_mask': 57344}), ({'w': 20, 'h': 4, 'x': 15, 'y': 2, 'plane': 2, 'base': 11}, {'words': 2, 'row_words': 3, 'row_bytes': 6, 'plane_bytes': 28, 'plane_origin': 71, 'word_column': 0, 'bit_index': 0, 'mask': 1, 'address': 83, 'last_word_mask': 61440}), ({'w': 21, 'h': 5, 'x': 16, 'y': 3, 'plane': 3, 'base': 11}, {'words': 2, 'row_words': 3, 'row_bytes': 6, 'plane_bytes': 34, 'plane_origin': 117, 'word_column': 1, 'bit_index': 15, 'mask': 32768, 'address': 137, 'last_word_mask': 63488}), ({'w': 22, 'h': 6, 'x': 17, 'y': 4, 'plane': 0, 'base': 11}, {'words': 2, 'row_words': 3, 'row_bytes': 6, 'plane_bytes': 40, 'plane_origin': 15, 'word_column': 1, 'bit_index': 14, 'mask': 16384, 'address': 41, 'last_word_mask': 64512}), ({'w': 23, 'h': 7, 'x': 18, 'y': 5, 'plane': 1, 'base': 11}, {'words': 2, 'row_words': 3, 'row_bytes': 6, 'plane_bytes': 46, 'plane_origin': 61, 'word_column': 1, 'bit_index': 13, 'mask': 8192, 'address': 93, 'last_word_mask': 65024})], 2: [({'w': 19, 'h': 2, 'x': 0, 'y': 0, 'plane': 0, 'base': 22}, {'words': 2, 'row_words': 3, 'row_bytes': 6, 'plane_bytes': 16, 'plane_origin': 26, 'word_column': 0, 'bit_index': 15, 'mask': 32768, 'address': 26, 'last_word_mask': 57344}), ({'w': 20, 'h': 3, 'x': 1, 'y': 1, 'plane': 1, 'base': 22}, {'words': 2, 'row_words': 3, 'row_bytes': 6, 'plane_bytes': 22, 'plane_origin': 48, 'word_column': 0, 'bit_index': 14, 'mask': 16384, 'address': 54, 'last_word_mask': 61440}), ({'w': 21, 'h': 4, 'x': 15, 'y': 2, 'plane': 2, 'base': 22}, {'words': 2, 'row_words': 3, 'row_bytes': 6, 'plane_bytes': 28, 'plane_origin': 82, 'word_column': 0, 'bit_index': 0, 'mask': 1, 'address': 94, 'last_word_mask': 63488}), ({'w': 22, 'h': 5, 'x': 16, 'y': 3, 'plane': 3, 'base': 22}, {'words': 2, 'row_words': 3, 'row_bytes': 6, 'plane_bytes': 34, 'plane_origin': 128, 'word_column': 1, 'bit_index': 15, 'mask': 32768, 'address': 148, 'last_word_mask': 64512}), ({'w': 23, 'h': 6, 'x': 17, 'y': 4, 'plane': 0, 'base': 22}, {'words': 2, 'row_words': 3, 'row_bytes': 6, 'plane_bytes': 40, 'plane_origin': 26, 'word_column': 1, 'bit_index': 14, 'mask': 16384, 'address': 52, 'last_word_mask': 65024}), ({'w': 24, 'h': 7, 'x': 18, 'y': 5, 'plane': 1, 'base': 22}, {'words': 2, 'row_words': 3, 'row_bytes': 6, 'plane_bytes': 46, 'plane_origin': 72, 'word_column': 1, 'bit_index': 13, 'mask': 8192, 'address': 104, 'last_word_mask': 65280})], 3: [({'w': 20, 'h': 2, 'x': 0, 'y': 0, 'plane': 0, 'base': 33}, {'words': 2, 'row_words': 3, 'row_bytes': 6, 'plane_bytes': 16, 'plane_origin': 37, 'word_column': 0, 'bit_index': 15, 'mask': 32768, 'address': 37, 'last_word_mask': 61440}), ({'w': 21, 'h': 3, 'x': 1, 'y': 1, 'plane': 1, 'base': 33}, {'words': 2, 'row_words': 3, 'row_bytes': 6, 'plane_bytes': 22, 'plane_origin': 59, 'word_column': 0, 'bit_index': 14, 'mask': 16384, 'address': 65, 'last_word_mask': 63488}), ({'w': 22, 'h': 4, 'x': 15, 'y': 2, 'plane': 2, 'base': 33}, {'words': 2, 'row_words': 3, 'row_bytes': 6, 'plane_bytes': 28, 'plane_origin': 93, 'word_column': 0, 'bit_index': 0, 'mask': 1, 'address': 105, 'last_word_mask': 64512}), ({'w': 23, 'h': 5, 'x': 16, 'y': 3, 'plane': 3, 'base': 33}, {'words': 2, 'row_words': 3, 'row_bytes': 6, 'plane_bytes': 34, 'plane_origin': 139, 'word_column': 1, 'bit_index': 15, 'mask': 32768, 'address': 159, 'last_word_mask': 65024}), ({'w': 24, 'h': 6, 'x': 17, 'y': 4, 'plane': 0, 'base': 33}, {'words': 2, 'row_words': 3, 'row_bytes': 6, 'plane_bytes': 40, 'plane_origin': 37, 'word_column': 1, 'bit_index': 14, 'mask': 16384, 'address': 63, 'last_word_mask': 65280}), ({'w': 25, 'h': 7, 'x': 18, 'y': 5, 'plane': 1, 'base': 33}, {'words': 2, 'row_words': 3, 'row_bytes': 6, 'plane_bytes': 46, 'plane_origin': 83, 'word_column': 1, 'bit_index': 13, 'mask': 8192, 'address': 115, 'last_word_mask': 65408})], 4: [({'w': 21, 'h': 2, 'x': 0, 'y': 0, 'plane': 0, 'base': 44}, {'words': 2, 'row_words': 3, 'row_bytes': 6, 'plane_bytes': 16, 'plane_origin': 48, 'word_column': 0, 'bit_index': 15, 'mask': 32768, 'address': 48, 'last_word_mask': 63488}), ({'w': 22, 'h': 3, 'x': 1, 'y': 1, 'plane': 1, 'base': 44}, {'words': 2, 'row_words': 3, 'row_bytes': 6, 'plane_bytes': 22, 'plane_origin': 70, 'word_column': 0, 'bit_index': 14, 'mask': 16384, 'address': 76, 'last_word_mask': 64512}), ({'w': 23, 'h': 4, 'x': 15, 'y': 2, 'plane': 2, 'base': 44}, {'words': 2, 'row_words': 3, 'row_bytes': 6, 'plane_bytes': 28, 'plane_origin': 104, 'word_column': 0, 'bit_index': 0, 'mask': 1, 'address': 116, 'last_word_mask': 65024}), ({'w': 24, 'h': 5, 'x': 16, 'y': 3, 'plane': 3, 'base': 44}, {'words': 2, 'row_words': 3, 'row_bytes': 6, 'plane_bytes': 34, 'plane_origin': 150, 'word_column': 1, 'bit_index': 15, 'mask': 32768, 'address': 170, 'last_word_mask': 65280}), ({'w': 25, 'h': 6, 'x': 17, 'y': 4, 'plane': 0, 'base': 44}, {'words': 2, 'row_words': 3, 'row_bytes': 6, 'plane_bytes': 40, 'plane_origin': 48, 'word_column': 1, 'bit_index': 14, 'mask': 16384, 'address': 74, 'last_word_mask': 65408}), ({'w': 26, 'h': 7, 'x': 18, 'y': 5, 'plane': 1, 'base': 44}, {'words': 2, 'row_words': 3, 'row_bytes': 6, 'plane_bytes': 46, 'plane_origin': 94, 'word_column': 1, 'bit_index': 13, 'mask': 8192, 'address': 126, 'last_word_mask': 65472})], 5: [({'w': 22, 'h': 2, 'x': 0, 'y': 0, 'plane': 0, 'base': 55}, {'words': 2, 'row_words': 3, 'row_bytes': 6, 'plane_bytes': 16, 'plane_origin': 59, 'word_column': 0, 'bit_index': 15, 'mask': 32768, 'address': 59, 'last_word_mask': 64512}), ({'w': 23, 'h': 3, 'x': 1, 'y': 1, 'plane': 1, 'base': 55}, {'words': 2, 'row_words': 3, 'row_bytes': 6, 'plane_bytes': 22, 'plane_origin': 81, 'word_column': 0, 'bit_index': 14, 'mask': 16384, 'address': 87, 'last_word_mask': 65024}), ({'w': 24, 'h': 4, 'x': 15, 'y': 2, 'plane': 2, 'base': 55}, {'words': 2, 'row_words': 3, 'row_bytes': 6, 'plane_bytes': 28, 'plane_origin': 115, 'word_column': 0, 'bit_index': 0, 'mask': 1, 'address': 127, 'last_word_mask': 65280}), ({'w': 25, 'h': 5, 'x': 16, 'y': 3, 'plane': 3, 'base': 55}, {'words': 2, 'row_words': 3, 'row_bytes': 6, 'plane_bytes': 34, 'plane_origin': 161, 'word_column': 1, 'bit_index': 15, 'mask': 32768, 'address': 181, 'last_word_mask': 65408}), ({'w': 26, 'h': 6, 'x': 17, 'y': 4, 'plane': 0, 'base': 55}, {'words': 2, 'row_words': 3, 'row_bytes': 6, 'plane_bytes': 40, 'plane_origin': 59, 'word_column': 1, 'bit_index': 14, 'mask': 16384, 'address': 85, 'last_word_mask': 65472}), ({'w': 27, 'h': 7, 'x': 18, 'y': 5, 'plane': 1, 'base': 55}, {'words': 2, 'row_words': 3, 'row_bytes': 6, 'plane_bytes': 46, 'plane_origin': 105, 'word_column': 1, 'bit_index': 13, 'mask': 8192, 'address': 137, 'last_word_mask': 65504})]}
for i, (p, expected) in enumerate(cases[N]):
    check("layout fixture " + str(i + 1), solve(p), expected)
print(json.dumps({"observations": observations, "passed": all(x["passed"] for x in observations)}, ensure_ascii=False))
raise SystemExit(0 if all(x["passed"] for x in observations) else 1)
Boundary fixtureActualExpectedOutcome
layout fixture 1{'address': 15, 'bit_index': 15, 'last_word_mask': 65535, 'mask': 32768, 'plane_bytes': 16, 'plane_origin': 15, 'row_bytes': 6, 'row_words': 3, 'word_column': 0, 'words': 2}{'address': 15, 'bit_index': 15, 'last_word_mask': 49152, 'mask': 32768, 'plane_bytes': 16, 'plane_origin': 15, 'row_bytes': 6, 'row_words': 3, 'word_column': 0, 'words': 2}Failed
layout fixture 2{'address': 43, 'bit_index': 14, 'last_word_mask': 65535, 'mask': 16384, 'plane_bytes': 22, 'plane_origin': 37, 'row_bytes': 6, 'row_words': 3, 'word_column': 0, 'words': 2}{'address': 43, 'bit_index': 14, 'last_word_mask': 57344, 'mask': 16384, 'plane_bytes': 22, 'plane_origin': 37, 'row_bytes': 6, 'row_words': 3, 'word_column': 0, 'words': 2}Failed
layout fixture 3{'address': 83, 'bit_index': 0, 'last_word_mask': 65535, 'mask': 1, 'plane_bytes': 28, 'plane_origin': 71, 'row_bytes': 6, 'row_words': 3, 'word_column': 0, 'words': 2}{'address': 83, 'bit_index': 0, 'last_word_mask': 61440, 'mask': 1, 'plane_bytes': 28, 'plane_origin': 71, 'row_bytes': 6, 'row_words': 3, 'word_column': 0, 'words': 2}Failed
layout fixture 4{'address': 137, 'bit_index': 15, 'last_word_mask': 65535, 'mask': 32768, 'plane_bytes': 34, 'plane_origin': 117, 'row_bytes': 6, 'row_words': 3, 'word_column': 1, 'words': 2}{'address': 137, 'bit_index': 15, 'last_word_mask': 63488, 'mask': 32768, 'plane_bytes': 34, 'plane_origin': 117, 'row_bytes': 6, 'row_words': 3, 'word_column': 1, 'words': 2}Failed
layout fixture 5{'address': 41, 'bit_index': 14, 'last_word_mask': 65535, 'mask': 16384, 'plane_bytes': 40, 'plane_origin': 15, 'row_bytes': 6, 'row_words': 3, 'word_column': 1, 'words': 2}{'address': 41, 'bit_index': 14, 'last_word_mask': 64512, 'mask': 16384, 'plane_bytes': 40, 'plane_origin': 15, 'row_bytes': 6, 'row_words': 3, 'word_column': 1, 'words': 2}Failed
layout fixture 6{'address': 93, 'bit_index': 13, 'last_word_mask': 65535, 'mask': 8192, 'plane_bytes': 46, 'plane_origin': 61, 'row_bytes': 6, 'row_words': 3, 'word_column': 1, 'words': 2}{'address': 93, 'bit_index': 13, 'last_word_mask': 65024, 'mask': 8192, 'plane_bytes': 46, 'plane_origin': 61, 'row_bytes': 6, 'row_words': 3, 'word_column': 1, 'words': 2}Failed

SHA-256 / 5df4a476f9af8a2ae5794388a6985045a3903e9e55e03cced0ffc026810f121a

HELD IN THE MEMBER ARCHIVE

The verified repair and its recorded checks are member-only.

This mechanism has 6 recorded checks per implementation. The open-access tier publishes the failure and the unsuccessful fix; the repaired source that passes every check, and the observations that prove it, are available to members.

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Verification & scope

Stipulated deterministic toy buffer layout; not a graphics API, codec, GPU vendor tiling specification, or hardware-conformance claim. Inputs satisfy the dimensions and bounds stated by the model. This reproducer isolates one failure mechanism. Results cover the supplied fixtures. Variants within a family share a test contract and should remain grouped when constructing evaluation splits. Related mechanisms with a shared evaluation_group must also remain together; these controlled models are not independent production incidents.

Observations recorded using Python 3.12.14 at 2026-09-29T14:45:28.420523+00:00.

Case digest / 187ac73ef674bb5270d78e3de335e7695e8a7501ce8c52b82234a588bca7cf67