Faster CBMC stubs for memset and memcpy #300
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.cbmc-batch/jobs/memcpy_using_uint64/memcpy_using_uint64_harness.c
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| uint64_t *d = (uint64_t *)dst; | ||
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| for (size_t i = 0; i < num_uint64s; ++i) { | ||
| d[i] = 0; |
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Shouldn't this be d[i] = c; or am I missing something?
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This harness is specialized for the common case of memset(0 ...). It uses 0 as the assignment here to let CBMC do more constant propagation. This is safe because of the assert here
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Description of changes:
When CBMC processes a
memcpyormemset, it ends up doing many invocations of the array theory, which is expensive. Instead, provide CBMC stubs which use 64 bit arithmetic, which in practice often proves to lead to quicker proofs.Each new implementation has a CBMC proof that it is functionally equivalent to a naive implementation.
By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.