support zero-initialized memory detection

This commit is contained in:
daan 2019-09-02 13:16:52 -07:00
parent 216d75a222
commit d1bd1644d5
9 changed files with 123 additions and 48 deletions

View file

@ -585,8 +585,9 @@ static void* mi_os_page_align_area_conservative(void* addr, size_t size, size_t*
// Commit/Decommit memory.
// Usuelly commit is aligned liberal, while decommit is aligned conservative.
// (but not for the reset version where we want commit to be conservative as well)
static bool mi_os_commitx(void* addr, size_t size, bool commit, bool conservative, mi_stats_t* stats) {
static bool mi_os_commitx(void* addr, size_t size, bool commit, bool conservative, bool* is_zero, mi_stats_t* stats) {
// page align in the range, commit liberally, decommit conservative
*is_zero = false;
size_t csize;
void* start = mi_os_page_align_areax(conservative, addr, size, &csize);
if (csize == 0 || _mi_os_is_huge_reserved(addr)) return true;
@ -600,6 +601,7 @@ static bool mi_os_commitx(void* addr, size_t size, bool commit, bool conservativ
}
#if defined(_WIN32)
*is_zero = true;
if (commit) {
void* p = VirtualAlloc(start, csize, MEM_COMMIT, PAGE_READWRITE);
err = (p == start ? 0 : GetLastError());
@ -620,16 +622,17 @@ static bool mi_os_commitx(void* addr, size_t size, bool commit, bool conservativ
return (err == 0);
}
bool _mi_os_commit(void* addr, size_t size, mi_stats_t* stats) {
return mi_os_commitx(addr, size, true, false /* conservative? */, stats);
bool _mi_os_commit(void* addr, size_t size, bool* is_zero, mi_stats_t* stats) {
return mi_os_commitx(addr, size, true, false /* conservative? */, is_zero, stats);
}
bool _mi_os_decommit(void* addr, size_t size, mi_stats_t* stats) {
return mi_os_commitx(addr, size, false, true /* conservative? */, stats);
bool is_zero;
return mi_os_commitx(addr, size, false, true /* conservative? */, &is_zero, stats);
}
bool _mi_os_commit_unreset(void* addr, size_t size, mi_stats_t* stats) {
return mi_os_commitx(addr, size, true, true /* conservative? */, stats);
bool _mi_os_commit_unreset(void* addr, size_t size, bool* is_zero, mi_stats_t* stats) {
return mi_os_commitx(addr, size, true, true /* conservative? */, is_zero, stats);
}
@ -698,11 +701,12 @@ bool _mi_os_reset(void* addr, size_t size, mi_stats_t* stats) {
}
}
bool _mi_os_unreset(void* addr, size_t size, mi_stats_t* stats) {
bool _mi_os_unreset(void* addr, size_t size, bool* is_zero, mi_stats_t* stats) {
if (mi_option_is_enabled(mi_option_reset_decommits)) {
return _mi_os_commit_unreset(addr, size, stats); // re-commit it (conservatively!)
return _mi_os_commit_unreset(addr, size, is_zero, stats); // re-commit it (conservatively!)
}
else {
*is_zero = false;
return mi_os_resetx(addr, size, false, stats);
}
}