Import optimized bit math from Solady

Aperture-Finance · Dec 31, 2023 · 2c53136 · 2c53136
1 parent 0798579
commit 2c53136
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Showing 3 changed files with 21 additions and 36 deletions.
diff --git a/.gas-snapshot b/.gas-snapshot
@@ -1,8 +1,8 @@
 BitMathTest:testFuzz_LSB(uint256) (runs: 65536, μ: 14911, ~: 14909)
-BitMathTest:testFuzz_MSB(uint256) (runs: 65536, μ: 14791, ~: 14816)
+BitMathTest:testFuzz_MSB(uint256) (runs: 65536, μ: 14771, ~: 14796)
 BitMathTest:testGas_LSB() (gas: 193393)
 BitMathTest:testGas_LSB_Og() (gas: 291088)
-BitMathTest:testGas_MSB() (gas: 213472)
+BitMathTest:testGas_MSB() (gas: 208372)
 BitMathTest:testGas_MSB_Og() (gas: 274437)
 FullMathTest:testFuzz_MulDiv96(uint256,uint256) (runs: 65536, μ: 3601, ~: 3585)
 FullMathTest:testFuzz_MulDivUp_OZ(uint256,uint256,uint256) (runs: 65536, μ: 4391, ~: 4237)
@@ -107,21 +107,21 @@ SwapMathTest:testGas_ComputeSwapStepExactIn_Og() (gas: 515722)
 SwapMathTest:testGas_ComputeSwapStepExactOut() (gas: 370755)
 SwapMathTest:testGas_ComputeSwapStepExactOut_Og() (gas: 510266)
 SwapMathTest:testGas_ComputeSwapStep_Og() (gas: 526558)
-TickBitmapTest:testFuzz_Compress(int24,int24) (runs: 65536, μ: 8348, ~: 8393)
-TickBitmapTest:testFuzz_FlipTick(int24) (runs: 65536, μ: 61584, ~: 61590)
-TickBitmapTest:testFuzz_NextInitializedTickWithinOneWord(int24,uint8,bool) (runs: 65536, μ: 67891, ~: 67871)
+TickBitmapTest:testFuzz_Compress(int24,int24) (runs: 65536, μ: 8348, ~: 8382)
+TickBitmapTest:testFuzz_FlipTick(int24) (runs: 65536, μ: 61570, ~: 61576)
+TickBitmapTest:testFuzz_NextInitializedTickWithinOneWord(int24,uint8,bool) (runs: 65536, μ: 67880, ~: 67868)
 TickBitmapTest:testFuzz_Position(int24) (runs: 65536, μ: 498, ~: 498)
-TickBitmapTest:testGas_NextInitializedTickWithinOneWord() (gas: 6776007)
+TickBitmapTest:testGas_NextInitializedTickWithinOneWord() (gas: 6769095)
 TickBitmapTest:testGas_NextInitializedTickWithinOneWord_Og() (gas: 7050256)
 TickBitmapTest:test_NextInitializedTickWithinOneWord_GT() (gas: 203148)
-TickBitmapTest:test_NextInitializedTickWithinOneWord_LTE() (gas: 212522)
+TickBitmapTest:test_NextInitializedTickWithinOneWord_LTE() (gas: 204586)
 TickBitmapTest:test_NextInitializedTick_GT() (gas: 342054)
-TickBitmapTest:test_NextInitializedTick_LTE() (gas: 399975)
-TickMathTest:testFuzz_GetSqrtRatioAtTick(int24) (runs: 65536, μ: 16536, ~: 16831)
-TickMathTest:testFuzz_GetTickAtSqrtRatio(uint160) (runs: 65536, μ: 13140, ~: 13159)
+TickBitmapTest:test_NextInitializedTick_LTE() (gas: 388455)
+TickMathTest:testFuzz_GetSqrtRatioAtTick(int24) (runs: 65536, μ: 16522, ~: 16817)
+TickMathTest:testFuzz_GetTickAtSqrtRatio(uint160) (runs: 65536, μ: 13125, ~: 13145)
 TickMathTest:testGas_GetSqrtRatioAtTick() (gas: 146478)
 TickMathTest:testGas_GetSqrtRatioAtTick_Og() (gas: 168547)
-TickMathTest:testGas_GetTickAtSqrtRatio() (gas: 252577)
+TickMathTest:testGas_GetTickAtSqrtRatio() (gas: 251177)
 TickMathTest:testGas_GetTickAtSqrtRatio_Og() (gas: 307790)
 TickMathTest:testRevert_GetSqrtRatioAtTick() (gas: 10445)
 TickMathTest:testRevert_GetTickAtSqrtRatio() (gas: 10522)
diff --git a/src/BitMath.sol b/src/BitMath.sol
@@ -21,21 +21,13 @@ library BitMath {
             r := or(r, shl(6, lt(0xffffffffffffffff, shr(r, x))))
             // r += (x >> r) >= 2**32 ? 32 : 0
             r := or(r, shl(5, lt(0xffffffff, shr(r, x))))
-
-            // For the remaining 32 bits, use a De Bruijn lookup.
-            // https://graphics.stanford.edu/~seander/bithacks.html#IntegerLogDeBruijn
-            x := shr(r, x)
-            x := or(x, shr(1, x))
-            x := or(x, shr(2, x))
-            x := or(x, shr(4, x))
-            x := or(x, shr(8, x))
-            x := or(x, shr(16, x))
-
+            r := or(r, shl(4, lt(0xffff, shr(r, x))))
+            r := or(r, shl(3, lt(0xff, shr(r, x))))
             r := or(
                 r,
                 byte(
-                    shr(251, mul(x, shl(224, 0x07c4acdd))),
-                    0x0009010a0d15021d0b0e10121619031e080c141c0f111807131b17061a05041f
+                    and(0x1f, shr(shr(r, x), 0x8421084210842108cc6318c6db6d54be)),
+                    0x0706060506020504060203020504030106050205030304010505030400000000
                 )
             )
         }
@@ -65,8 +57,8 @@ library BitMath {
             r := or(
                 r,
                 byte(
-                    shr(251, mul(shr(r, x), shl(224, 0x077cb531))),
-                    0x00011c021d0e18031e16140f191104081f1b0d17151310071a0c12060b050a09
+                    and(div(0xd76453e0, shr(r, x)), 0x1f),
+                    0x001f0d1e100c1d070f090b19131c1706010e11080a1a141802121b1503160405
                 )
             )
         }

diff --git a/src/TickMath.sol b/src/TickMath.sol
@@ -135,20 +135,13 @@ library TickMath {
             msb := shl(7, lt(0xffffffffffffffffffffffffffffffff, x))
             msb := or(msb, shl(6, lt(0xffffffffffffffff, shr(msb, x))))
             msb := or(msb, shl(5, lt(0xffffffff, shr(msb, x))))
-
-            // For the remaining 32 bits, use a De Bruijn lookup.
-            x := shr(msb, x)
-            x := or(x, shr(1, x))
-            x := or(x, shr(2, x))
-            x := or(x, shr(4, x))
-            x := or(x, shr(8, x))
-            x := or(x, shr(16, x))
-
+            msb := or(msb, shl(4, lt(0xffff, shr(msb, x))))
+            msb := or(msb, shl(3, lt(0xff, shr(msb, x))))
             msb := or(
                 msb,
                 byte(
-                    shr(251, mul(x, shl(224, 0x07c4acdd))),
-                    0x0009010a0d15021d0b0e10121619031e080c141c0f111807131b17061a05041f
+                    and(0x1f, shr(shr(msb, x), 0x8421084210842108cc6318c6db6d54be)),
+                    0x0706060506020504060203020504030106050205030304010505030400000000
                 )
             )
         }