02ca710872
This PR adds support the Count Trailing Zeros operation `BitVec.ctz` to the bitvector library and to `bv_decide`, relying on the existing `clz` circuit. We also build some theory around `BitVec.ctz` (analogous to the theory existing for `BitVec.clz`) and introduce lemmas `BitVec.[ctz_eq_reverse_clz, clz_eq_reverse_ctz, ctz_lt_iff_ne_zero, getLsbD_false_of_lt_ctz, getLsbD_true_ctz_of_ne_zero, two_pow_ctz_le_toNat_of_ne_zero, reverse_reverse_eq, reverse_eq_zero_iff]`. `ctz` operation is common in numerous compiler intrinsics (see [here](https://clang.llvm.org/docs/LanguageExtensions.html#intrinsics-support-within-constant-expressions)) and architectures (see [here](https://en.wikipedia.org/wiki/Find_first_set)). --------- Co-authored-by: Siddharth <siddu.druid@gmail.com> |
||
|---|---|---|
| .. | ||
| bench | ||
| compiler | ||
| elabissues | ||
| ir | ||
| lean | ||
| pkg | ||
| playground | ||
| plugin | ||
| simpperf | ||
| .gitignore | ||
| common.sh | ||
| lakefile.toml | ||
| lean-toolchain | ||