Improve Initializable readability using intermediate variables #4576
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🦋 Changeset detectedLatest commit: 175b1e9 The changes in this PR will be included in the next version bump. This PR includes changesets to release 1 package
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Co-authored-by: Francisco <fg@frang.io>
Co-authored-by: Francisco <fg@frang.io>
| bool initialSetup = initialized == 0 && isTopLevelCall; | ||
| bool construction = initialized == 1 && address(this).code.length == 0; | ||
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| if (!initialSetup && !construction) { | ||
| revert AlreadyInitialized(); | ||
| } | ||
| $._initialized = 1; |
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$._initialized = 1;
$._initializing = isTopLevelCall;
May be cheaper here, removing redundant SLOAD operation in case of !isTopLevelCall
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I'm not sure I understand your proposal. Before doing _;, we want to make sure the initializing is true, this would possibly invert it to false.
Also I'm not sure where the duplicated sload is.
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Also I'm not sure where the duplicated sload is.
Since $ is a struct with two fields packed in one storage slot, compiler need to load this slot if you change only one field. If you write all the fields of the structure at once, the compiler does not need to read this slot before SSTORE
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So it could (in theory) save around 100 gas here
openzeppelin-contracts/contracts/proxy/utils/Initializable.sol
Lines 122 to 125 in 175b1e9
If do it like
$._initialized = 1;
$._initializing = isTopLevelCall;There was a problem hiding this comment.
this would possibly invert it to false
Upd: yes, in this case my proposal should be rather:
$._initialized = 1;
$._initializing = true;And here:
$._initialized = 1;
$._initializing = false;
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Writing it that way requires proving that the _; part doesn't change the value of $._initialized.
I think it is true, because $._initializing = true prevents that value from changing in the rest of the contract, but it's more difficult to see.
I think I prefer to keep the current code at this stage (audit fixes) and come back to this for a future release. @vladyan18 can you open an issue?
Fixes LIB-1041
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