08eb78a5b2
This PR sets up the new integrated test/bench suite. It then migrates all benchmarks and some related tests to the new suite. There's also some documentation and some linting. For now, a lot of the old tests are left alone so this PR doesn't become even larger than it already is. Eventually, all tests should be migrated to the new suite though so there isn't a confusing mix of two systems.
57 lines
1.4 KiB
Text
57 lines
1.4 KiB
Text
import Std.Tactic.BVDecide
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/-
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This is based on: https://saw.galois.com/intro/IntroToSAW.html#the-code
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-/
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namespace Popcount
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/-
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int pop_spec(uint32_t x) {
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uint32_t pop = 0;
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uint32_t mask = 1;
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for (int i = 0; i < 32; i++) {
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if (x & mask) { pop++; }
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mask = mask << 1;
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}
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return pop;
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}
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-/
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def pop_spec (x : BitVec 32) : BitVec 32 := Id.run do
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let mut pop : BitVec 32 := 0
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let mut mask : BitVec 32 := 1
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for _ in *...(32 : Nat) do
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if (x &&& mask != 0) then
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pop := pop + 1
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mask := mask <<< 1
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return pop
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/-
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We do currently not have nice support for if statements in the bit blaster and arguing about
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monadic for loops is not nicely done as well, instead we will use a recursive version:
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-/
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def pop_spec' (x : BitVec 32) : BitVec 32 :=
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go x 0 32
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where
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go (x : BitVec 32) (pop : BitVec 32) (i : Nat) : BitVec 32 :=
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match i with
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| 0 => pop
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| i + 1 =>
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let pop := pop + (x &&& 1)
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go (x >>> 1) pop i
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def optimized (x : BitVec 32) : BitVec 32 :=
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let x := x - ((x >>> 1) &&& 0x55555555);
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let x := (x &&& 0x33333333) + ((x >>> 2) &&& 0x33333333);
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let x := (x + (x >>> 4)) &&& 0x0F0F0F0F;
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let x := x + (x >>> 8);
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let x := x + (x >>> 16);
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x &&& 0x0000003F
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example (x : BitVec 32) : pop_spec' x = optimized x := by
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dsimp [pop_spec', pop_spec'.go, optimized]
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bv_decide
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end Popcount
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