rust/src/rt/rust_stack.cpp

62 lines
1.6 KiB
C++

#include "rust_internal.h"
#include "vg/valgrind.h"
#include "vg/memcheck.h"
#ifdef _LP64
const uintptr_t canary_value = 0xABCDABCDABCDABCD;
#else
const uintptr_t canary_value = 0xABCDABCD;
#endif
void
register_valgrind_stack(stk_seg *stk) {
stk->valgrind_id =
VALGRIND_STACK_REGISTER(&stk->data[0],
stk->end);
}
void
reuse_valgrind_stack(stk_seg *stk, uint8_t *sp) {
// Establish that the stack is accessible. This must be done when reusing
// old stack segments, since the act of popping the stack previously
// caused valgrind to consider the whole thing inaccessible.
assert(sp >= stk->data && sp <= (uint8_t*) stk->end
&& "Stack pointer must be inside stack segment");
size_t sz = stk->end - (uintptr_t)sp;
(void) VALGRIND_MAKE_MEM_UNDEFINED(sp, sz);
(void) sz;
}
void
deregister_valgrind_stack(stk_seg *stk) {
VALGRIND_STACK_DEREGISTER(stk->valgrind_id);
}
void
add_stack_canary(stk_seg *stk) {
stk->canary = canary_value;
}
void
check_stack_canary(stk_seg *stk) {
assert(stk->canary == canary_value && "Somebody killed the canary");
}
stk_seg *
create_stack(memory_region *region, size_t sz) {
size_t total_sz = sizeof(stk_seg) + sz;
stk_seg *stk = (stk_seg *)region->malloc(total_sz, "stack", false);
memset(stk, 0, sizeof(stk_seg));
stk->end = (uintptr_t) &stk->data[sz];
add_stack_canary(stk);
register_valgrind_stack(stk);
return stk;
}
void
destroy_stack(memory_region *region, stk_seg *stk) {
deregister_valgrind_stack(stk);
region->free(stk);
}