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/**
* Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
* SPDX-License-Identifier: Apache-2.0.
*/
#undef memset
#include <proof_helpers/nondet.h>
#include <stddef.h>
/**
* Override the version of memset used by CBMC. Users may not want to pay
* for the cost of performing the computation of memset in proofs. In that
* case, this stub at least checks for the preconditions and make sure to
* havoc all elements pointed by *s up to n.
*/
void *memset_impl(void *s, int c, size_t n) {
__CPROVER_precondition(__CPROVER_w_ok(s, n), "memset destination region writeable");
if (n > 0) {
size_t index;
__CPROVER_assume(index < n);
((uint8_t *)s)[index] = nondet_uint8_t();
}
return s;
}
void *memset(void *s, int c, size_t n) {
return memset_impl(s, c, n);
}
void *__builtin___memset_chk(void *s, int c, size_t n, size_t os) {
(void)os;
return memset_impl(s, c, n);
}
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