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Avoid safe math in BitMap (#2797)

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This commit is contained in:
Anton Bukov
2021-07-30 10:48:45 +03:00
committed by GitHub
parent 566a774222
commit 3dadd40034
1 changed files with 6 additions and 6 deletions
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12
contracts/utils/structs/BitMaps.sol
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@ -14,8 +14,8 @@ library BitMaps {
* @dev Returns whether the bit at `index` is set.
*/
function get(BitMap storage bitmap, uint256 index) internal view returns (bool) {
uint256 bucket = index / 256;
uint256 mask = 1 << (index % 256);
uint256 bucket = index >> 8;
uint256 mask = 1 << (index & 0xff);
return bitmap._data[bucket] & mask != 0;
}
@ -38,8 +38,8 @@ library BitMaps {
* @dev Sets the bit at `index`.
*/
function set(BitMap storage bitmap, uint256 index) internal {
uint256 bucket = index / 256;
uint256 mask = 1 << (index % 256);
uint256 bucket = index >> 8;
uint256 mask = 1 << (index & 0xff);
bitmap._data[bucket] |= mask;
}
@ -47,8 +47,8 @@ library BitMaps {
* @dev Unsets the bit at `index`.
*/
function unset(BitMap storage bitmap, uint256 index) internal {
uint256 bucket = index / 256;
uint256 mask = 1 << (index % 256);
uint256 bucket = index >> 8;
uint256 mask = 1 << (index & 0xff);
bitmap._data[bucket] &= ~mask;
}
}