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| 1 | +// Code presented in https://github.com/diffblue/cbmc/issues/7690 |
| 2 | + |
| 3 | +// clang-format off |
| 4 | + |
| 5 | +#include <stdlib.h> |
| 6 | +#include <stdint.h> |
| 7 | + |
| 8 | +extern size_t __CPROVER_max_malloc_size; |
| 9 | +int __builtin_clzll(unsigned long long); |
| 10 | + |
| 11 | +#define __nof_symex_objects \ |
| 12 | + ((size_t)(1ULL << __builtin_clzll(__CPROVER_max_malloc_size))) |
| 13 | + |
| 14 | +typedef struct { |
| 15 | + size_t k; |
| 16 | + void **ptrs; |
| 17 | +} smap_t; |
| 18 | + |
| 19 | +void smap_init(smap_t *smap, size_t k) { |
| 20 | + *smap = (smap_t){ |
| 21 | + .k = k, .ptrs = __CPROVER_allocate(__nof_symex_objects * sizeof(void *), 1)}; |
| 22 | +} |
| 23 | + |
| 24 | +void *smap_get(smap_t *smap, void *ptr) { |
| 25 | + size_t id = __CPROVER_POINTER_OBJECT(ptr); |
| 26 | + char *sptr = smap->ptrs[id]; |
| 27 | + if (!sptr) { |
| 28 | + sptr = __CPROVER_allocate(smap->k * __CPROVER_OBJECT_SIZE(ptr), 1); |
| 29 | + smap->ptrs[id] = sptr; |
| 30 | + } |
| 31 | + return sptr + smap->k * __CPROVER_POINTER_OFFSET(ptr); |
| 32 | +} |
| 33 | + |
| 34 | +typedef struct { |
| 35 | + uint8_t key; |
| 36 | + uint8_t value; |
| 37 | +} stk_elem_t; |
| 38 | + |
| 39 | +typedef struct { |
| 40 | + int8_t top; |
| 41 | + stk_elem_t *elems; |
| 42 | +} stk_t; |
| 43 | + |
| 44 | +size_t nondet_size_t(); |
| 45 | + |
| 46 | +// Creates a fresh borrow stack |
| 47 | +stk_t *stk_new() { |
| 48 | + stk_t *stk = __CPROVER_allocate(sizeof(stk_t), 1); |
| 49 | + size_t stk_size = nondet_size_t(); |
| 50 | + __CPROVER_assume(UINT8_MAX <= stk_size && stk_size <= UINT8_MAX); |
| 51 | + // works with |
| 52 | + // __CPROVER_assume(stk_size == UINT8_MAX); |
| 53 | + *stk = (stk_t){ |
| 54 | + .top = 0, |
| 55 | + .elems = __CPROVER_allocate(sizeof(stk_elem_t) * stk_size, 1)}; |
| 56 | + return stk; |
| 57 | +} |
| 58 | + |
| 59 | +void stk_push(stk_t *stk, uint8_t key, uint8_t value) { |
| 60 | + assert(stk->top < UINT8_MAX); |
| 61 | + stk->elems[stk->top] = (stk_elem_t){.key = key, .value = value}; |
| 62 | + stk->top++; |
| 63 | +} |
| 64 | + |
| 65 | +stk_t *get_stk(smap_t *smap, void *ptr) { |
| 66 | + stk_t **stk_ptr = (stk_t **) smap_get(smap, ptr); |
| 67 | + if (!(*stk_ptr)) { |
| 68 | + *stk_ptr = stk_new(); |
| 69 | + } |
| 70 | + return *stk_ptr; |
| 71 | +} |
| 72 | + |
| 73 | +typedef struct { |
| 74 | + int a; |
| 75 | + int b; |
| 76 | +} my_struct_t; |
| 77 | + |
| 78 | +int main() { |
| 79 | + smap_t smap; |
| 80 | + smap_init(&smap, sizeof(stk_t*)); |
| 81 | + my_struct_t my_struct; |
| 82 | + stk_t *stk_a = get_stk(&smap, &(my_struct.a)); |
| 83 | + stk_push(stk_a, 1, 1); |
| 84 | + stk_t *stk_b = get_stk(&smap, &(my_struct.b)); |
| 85 | + assert(stk_b); |
| 86 | + stk_push(stk_b, 1, 1); |
| 87 | +} |
| 88 | + |
| 89 | +// clang-format on |
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