diff options
Diffstat (limited to 'compiler/bitsets.nim')
| -rw-r--r-- | compiler/bitsets.nim | 37 |
1 files changed, 19 insertions, 18 deletions
diff --git a/compiler/bitsets.nim b/compiler/bitsets.nim index 6afd1bd78..e38732877 100644 --- a/compiler/bitsets.nim +++ b/compiler/bitsets.nim @@ -72,24 +72,25 @@ proc bitSetContains(x, y: TBitSet): bool = result = true # Number of set bits for all values of int8 -const populationCount: array[low(int8)..high(int8), int8] = [ - 1.int8, 2, 2, 3, 2, 3, 3, 4, 2, 3, 3, 4, 3, 4, 4, 5, - 2, 3, 3, 4, 3, 4, 4, 5, 3, 4, 4, 5, 4, 5, 5, 6, - 2, 3, 3, 4, 3, 4, 4, 5, 3, 4, 4, 5, 4, 5, 5, 6, - 3, 4, 4, 5, 4, 5, 5, 6, 4, 5, 5, 6, 5, 6, 6, 7, - 2, 3, 3, 4, 3, 4, 4, 5, 3, 4, 4, 5, 4, 5, 5, 6, - 3, 4, 4, 5, 4, 5, 5, 6, 4, 5, 5, 6, 5, 6, 6, 7, - 3, 4, 4, 5, 4, 5, 5, 6, 4, 5, 5, 6, 5, 6, 6, 7, - 4, 5, 5, 6, 5, 6, 6, 7, 5, 6, 6, 7, 6, 7, 7, 8, - 0, 1, 1, 2, 1, 2, 2, 3, 1, 2, 2, 3, 2, 3, 3, 4, - 1, 2, 2, 3, 2, 3, 3, 4, 2, 3, 3, 4, 3, 4, 4, 5, - 1, 2, 2, 3, 2, 3, 3, 4, 2, 3, 3, 4, 3, 4, 4, 5, - 2, 3, 3, 4, 3, 4, 4, 5, 3, 4, 4, 5, 4, 5, 5, 6, - 1, 2, 2, 3, 2, 3, 3, 4, 2, 3, 3, 4, 3, 4, 4, 5, - 2, 3, 3, 4, 3, 4, 4, 5, 3, 4, 4, 5, 4, 5, 5, 6, - 2, 3, 3, 4, 3, 4, 4, 5, 3, 4, 4, 5, 4, 5, 5, 6, - 3, 4, 4, 5, 4, 5, 5, 6, 4, 5, 5, 6, 5, 6, 6, 7 -] +const populationCount: array[low(int8)..high(int8), int8] = block: + var arr: array[low(int8)..high(int8), int8] + + proc countSetBits(x: int8): int8 = + return + ( x and 0b00000001'i8) + + ((x and 0b00000010'i8) shr 1) + + ((x and 0b00000100'i8) shr 2) + + ((x and 0b00001000'i8) shr 3) + + ((x and 0b00010000'i8) shr 4) + + ((x and 0b00100000'i8) shr 5) + + ((x and 0b01000000'i8) shr 6) + + ((x and 0b10000000'i8) shr 7) + + + for it in low(int8)..high(int8): + arr[it] = countSetBits(it) + + arr proc bitSetCard(x: TBitSet): BiggestInt = for it in x: |