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Description
hevm takes a very long time to explore the following function (which despite how it looks, it is used frequently when dealing with ticks on dexes):
function getSqrtRatioAtTick(int24 tick) internal pure returns (uint160 price) {
unchecked {
// get abs value
int24 absTickMask = tick >> (24 - 1);
uint256 absTick = uint24((tick + absTickMask) ^ absTickMask);
if (absTick > uint24(MAX_TICK)) revert IAlgebraPoolErrors.tickOutOfRange();
uint256 ratio = 0x100000000000000000000000000000000;
if (absTick & 0x1 != 0) ratio = 0xfffcb933bd6fad37aa2d162d1a594001;
if (absTick & 0x2 != 0) ratio = (ratio * 0xfff97272373d413259a46990580e213a) >> 128;
if (absTick & 0x4 != 0) ratio = (ratio * 0xfff2e50f5f656932ef12357cf3c7fdcc) >> 128;
if (absTick & 0x8 != 0) ratio = (ratio * 0xffe5caca7e10e4e61c3624eaa0941cd0) >> 128;
if (absTick & 0x10 != 0) ratio = (ratio * 0xffcb9843d60f6159c9db58835c926644) >> 128;
if (absTick & 0x20 != 0) ratio = (ratio * 0xff973b41fa98c081472e6896dfb254c0) >> 128;
if (absTick & 0x40 != 0) ratio = (ratio * 0xff2ea16466c96a3843ec78b326b52861) >> 128;
if (absTick & 0x80 != 0) ratio = (ratio * 0xfe5dee046a99a2a811c461f1969c3053) >> 128;
if (absTick & 0x100 != 0) ratio = (ratio * 0xfcbe86c7900a88aedcffc83b479aa3a4) >> 128;
if (absTick & 0x200 != 0) ratio = (ratio * 0xf987a7253ac413176f2b074cf7815e54) >> 128;
if (absTick & 0x400 != 0) ratio = (ratio * 0xf3392b0822b70005940c7a398e4b70f3) >> 128;
if (absTick & 0x800 != 0) ratio = (ratio * 0xe7159475a2c29b7443b29c7fa6e889d9) >> 128;
if (absTick & 0x1000 != 0) ratio = (ratio * 0xd097f3bdfd2022b8845ad8f792aa5825) >> 128;
if (absTick & 0x2000 != 0) ratio = (ratio * 0xa9f746462d870fdf8a65dc1f90e061e5) >> 128;
if (absTick & 0x4000 != 0) ratio = (ratio * 0x70d869a156d2a1b890bb3df62baf32f7) >> 128;
if (absTick & 0x8000 != 0) ratio = (ratio * 0x31be135f97d08fd981231505542fcfa6) >> 128;
if (absTick & 0x10000 != 0) ratio = (ratio * 0x9aa508b5b7a84e1c677de54f3e99bc9) >> 128;
if (absTick & 0x20000 != 0) ratio = (ratio * 0x5d6af8dedb81196699c329225ee604) >> 128;
if (absTick >= 0x40000) {
if (absTick & 0x40000 != 0) ratio = (ratio * 0x2216e584f5fa1ea926041bedfe98) >> 128;
if (absTick & 0x80000 != 0) ratio = (ratio * 0x48a170391f7dc42444e8fa2) >> 128;
}
if (tick > 0) {
assembly {
ratio := div(not(0), ratio)
}
}
// this divides by 1<<32 rounding up to go from a Q128.128 to a Q128.96.
// we then downcast because we know the result always fits within 160 bits due to our tick input constraint
// we round up in the division so getTickAtSqrtRatio of the output price is always consistent
price = uint160((ratio + 0xFFFFFFFF) >> 32);
}
}When doing some profiling, it spend 99.9% of the time executing normArgs:
COST CENTRE MODULE SRC %time %alloc
normArgs EVM.Expr src/EVM/Expr.hs:(68,1)-(70,23) 99.9 0.0
linear Data.Profunctor.Indexed src/Data/Profunctor/Indexed.hs:296:3-69 0.0 23.1
>>= Data.Vector.Fusion.Util src/Data/Vector/Fusion/Util.hs:36:3-18 0.0 7.5
...
Is there a way to do it faster? Is simplification really needed for these kind of expressions ?