Optimize overflow check in mulDivRoundingUp
#667
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This commit optimizes the overflow check within the `mulDivRoundingUp` function of FullMath library. This is achieved by combining two steps: the increment of the `result` and the overflow check, into a single step using the `++` operator. This simplifies the code, improves its readability and brings down the gas usage slightly, as reflected in updated snapshot files.
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hensha256
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May 22, 2024
| require(result < type(uint256).max); | ||
| result++; | ||
| if (mulmod(a, b, denominator) != 0) { | ||
| require(++result > 0); |
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looks good. I see that the test test_fuzz_mulDivRoundingUp isn't very good because it checks
assertTrue(result == numerator / d || result == numerator / d + 1);
🥲
please could you update it to correctly identify whether it should have +1 or not with a mod?
hensha256
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May 23, 2024
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Factored out of #601.
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Description of changes
This commit optimizes the overflow check within the
mulDivRoundingUpfunction of FullMath library. This is achieved by combining two steps: the increment of theresultand the overflow check, into a single step using the++operator. This simplifies the code, improves its readability and brings down the gas usage slightly, as reflected in updated snapshot files.