atrosinenko added a comment. Here are the benchmark and fuzzing harness used to test this patch.
F12453076: fuzz_divXf3.sh <https://reviews.llvm.org/F12453076> F12453075: divXf3_fuzzer.c <https://reviews.llvm.org/F12453075> F12453074: bench_divXf3.sh <https://reviews.llvm.org/F12453074> F12453073: divXf3_bench.c <https://reviews.llvm.org/F12453073> ================ Comment at: compiler-rt/lib/builtins/fp_div_impl.inc:248-249 + if (quotient_UQ1 < (implicitBit << 1)) { + residualLo = (aSignificand << (significandBits + 1)) - quotient_UQ1 * bSignificand; + writtenExponent -= 1; + ---------------- Interesting fact: swapping these two seemingly commuting lines makes code slower by 15-25%. This applies to current Clang as well as to `clang-8` from Ubuntu 20.04 repository. Repository: rG LLVM Github Monorepo CHANGES SINCE LAST ACTION https://reviews.llvm.org/D85031/new/ https://reviews.llvm.org/D85031 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
