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clonker
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Apr 15, 2026
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here the guards are a bit strict perhaps. i managed to get rid of the regression in this particular case but that lead to overall worse results in the external contracts. ugh :)
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It definitely shows potential, but let's see if we can minimize the regressions.
| // if there are no args, we should be done now | ||
| if (_state.target().args.empty()) | ||
| return {StackShufflerResult::Status::Admissible}; | ||
| yulAssert(_stack.size() == _state.target().size); |
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Why is this not true anymore?
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previously, the fixArgsSlot couldn't refuse to grow and would, worst case, push junk. now it can refuse and ultimately yield NoAction in which case the invariant would be violated.
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argsRangeontargethelper, inspired from SSA: Fix cycle in stack shuffler #16595 (comment)fixArgsSlot:canReachSomeUnfilledTarget(arg)checking if there is a swap-reachable slot wantingarg, andprefixReachablechecking that, after growing the stack, every misaligned prefix offset is still reachablefixArgsSlot:argthe target wants at the new top directly) but only under a stricterpushKeepsDeepPrefixReachablegate: every misaligned prefix offset must survive the grow plus one more op. this accounts for committing the slot to its final position right away, which means that fixing a deeper slot requires duping/pushing something else first if that slot is in its final position