decompose: Remove separate input argument#798
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Some minor points on readability and documentation, otherwise LGTM
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To reduce stack usage, polyveck_decompose should be able to operate on one of the outputs aliasing the input. This is already fully supported but wasn't used to ease CBMC proofs/contracts at a cost of requiring additional stack space which is undesirable. This commit is an alternative to #792 which extended the CBMC contracts to allow aliasing. This commit instead, changes the signature of the decompose functions to take 2 arguments instead of 3, where the second output also acts as and input. The corresponding poly_ and native functions are adjusted accordingly. CBMC contracts/proofs and unit tests are adjusted to the new signature. The single callsite of polyveck_decompose is adjusted. Signed-off-by: Matthias J. Kannwischer <matthias@kannwischer.eu>
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To reduce stack usage, polyveck_decompose should be able to operate on one of the outputs aliasing the input. This is already fully supported but wasn't used to ease CBMC proofs/contracts at a cost of requiring additional stack space which is undesirable.
This commit is an alternative to
#792 which extended the CBMC contracts to allow aliasing.
This commit instead, changes the signature of the decompose functions to take 2 arguments instead of 3, where the second output also acts as and input. The corresponding poly_ and native functions are adjusted accordingly. CBMC contracts/proofs and unit tests are adjusted to the new signature. The single callsite of polyveck_decompose is adjusted.