Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

ASAN found _two_ bugs in _Copy_vbool! #4045

Merged
merged 3 commits into from
Sep 22, 2023
Merged

ASAN found _two_ bugs in _Copy_vbool! #4045

Changes from all commits
Commits
Show all changes
3 commits
Select commit Hold shift + click to select a range
0f375ce
ASAN found _two_ bugs in `_Copy_vbool`!
CaseyCarter Sep 22, 2023
06302e7
Ooops: forget to push this back up
CaseyCarter Sep 22, 2023
1f08c28
Stephan's review comments
CaseyCarter Sep 22, 2023
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
34 changes: 18 additions & 16 deletions stl/inc/vector
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -3748,7 +3748,7 @@ _CONSTEXPR20 _OutIt _Copy_vbool(_VbIt _First, _VbIt _Last, _OutIt _Dest) {
const auto _LastDestMask = static_cast<_Vbase>(-1) << _DestEnd._Myoff;

const bool _IsSingleBlockSource = _VbFirst == _VbLast;
const bool _IsSingleBlockDest = _VbDest == _DestEnd._Myptr;
const bool _IsSingleBlockDest = _VbDest == _DestEnd._Myptr - (_DestEnd._Myoff == 0 ? 1 : 0);
const bool _IsRightShift = _Dest._Myoff < _First._Myoff;
if (_IsSingleBlockSource) {
// We already excluded _First == _Last, so here _Last._Myoff > 0 and the shift is safe
Expand All @@ -3757,7 +3757,7 @@ _CONSTEXPR20 _OutIt _Copy_vbool(_VbIt _First, _VbIt _Last, _OutIt _Dest) {
const auto _SourceVal = _IsRightShift ? (*_VbFirst & _SourceMask) >> _SourceShift //
: (*_VbFirst & _SourceMask) << _SourceShift;
if (_IsSingleBlockDest) {
const auto _DestMask = _FirstDestMask | _LastDestMask;
const auto _DestMask = _FirstDestMask | (_DestEnd._Myoff == 0 ? 0 : _LastDestMask);
*_VbDest = (*_VbDest & _DestMask) | _SourceVal;
} else {
*_VbDest = (*_VbDest & _FirstDestMask) | _SourceVal;
Expand All @@ -3774,7 +3774,7 @@ _CONSTEXPR20 _OutIt _Copy_vbool(_VbIt _First, _VbIt _Last, _OutIt _Dest) {
const auto _SourceVal = _IsRightShift ? (*_VbFirst & _FirstSourceMask) >> _SourceShift //
: (*_VbFirst & _FirstSourceMask) << _SourceShift;

const auto _DestMask = _FirstDestMask | _LastDestMask;
const auto _DestMask = _FirstDestMask | (_DestEnd._Myoff == 0 ? 0 : _LastDestMask);
if (_Last._Myoff != 0) {
const auto _LastShift = _DestEnd._Myoff - _Last._Myoff;
const auto _LastSourceVal = (*_VbLast & _LastSourceMask) << _LastShift;
Expand Down Expand Up @@ -3842,20 +3842,22 @@ _CONSTEXPR20 _OutIt _Copy_vbool(_VbIt _First, _VbIt _Last, _OutIt _Dest) {
*_VbDest = (*_VbDest & _DestMask) | _SourceVal;
}

const auto _CarryVal = (*_VbFirst & _LastSourceMask) << _CarryShift;
if (_Last._Myoff >= _SourceShift) {
*_VbDest = (*_VbDest & _CarryMask) | _CarryVal;

// We have more bits remaining than the final block has left
if (_Last._Myoff != _SourceShift) {
++_VbDest;
const auto _SourceVal = (*_VbFirst & _LastSourceMask) >> _SourceShift;
*_VbDest = (*_VbDest & _LastDestMask) | _SourceVal;
if (_Last._Myoff != 0) {
const auto _CarryVal = (*_VbFirst & _LastSourceMask) << _CarryShift;
if (_Last._Myoff >= _SourceShift) {
*_VbDest = (*_VbDest & _CarryMask) | _CarryVal;

// We have more bits remaining than the final block has left
if (_Last._Myoff != _SourceShift) {
++_VbDest;
const auto _SourceVal = (*_VbFirst & _LastSourceMask) >> _SourceShift;
*_VbDest = (*_VbDest & _LastDestMask) | _SourceVal;
}
} else {
// There are not enough bits to fill the final block so we need to mask both ends
const auto _FinalMask = _CarryMask | _LastDestMask;
*_VbDest = (*_VbDest & _FinalMask) | _CarryVal;
CaseyCarter marked this conversation as resolved.
Show resolved Hide resolved
}
} else if (_Last._Myoff != 0) {
// There are not enough bits to fill the final block so we need to mask both ends
const auto _FinalMask = _CarryMask | _LastDestMask;
*_VbDest = (*_VbDest & _FinalMask) | _CarryVal;
}
} else {
const auto _SourceShift = _Dest._Myoff - _First._Myoff;
Expand Down