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-rw-r--r--absl/random/internal/distribution_impl.h66
1 files changed, 0 insertions, 66 deletions
diff --git a/absl/random/internal/distribution_impl.h b/absl/random/internal/distribution_impl.h
index 9b6ffb0..49b3e1a 100644
--- a/absl/random/internal/distribution_impl.h
+++ b/absl/random/internal/distribution_impl.h
@@ -188,72 +188,6 @@ struct RandU64ToReal<float> {
}
};
-inline uint128 MultiplyU64ToU128(uint64_t a, uint64_t b) {
-#if defined(ABSL_HAVE_INTRINSIC_INT128)
- return uint128(static_cast<__uint128_t>(a) * b);
-#elif defined(ABSL_INTERNAL_USE_UMUL128)
- // uint64_t * uint64_t => uint128 multiply using imul intrinsic on MSVC.
- uint64_t high = 0;
- const uint64_t low = _umul128(a, b, &high);
- return absl::MakeUint128(high, low);
-#else
- // uint128(a) * uint128(b) in emulated mode computes a full 128-bit x 128-bit
- // multiply. However there are many cases where that is not necessary, and it
- // is only necessary to support a 64-bit x 64-bit = 128-bit multiply. This is
- // for those cases.
- const uint64_t a00 = static_cast<uint32_t>(a);
- const uint64_t a32 = a >> 32;
- const uint64_t b00 = static_cast<uint32_t>(b);
- const uint64_t b32 = b >> 32;
-
- const uint64_t c00 = a00 * b00;
- const uint64_t c32a = a00 * b32;
- const uint64_t c32b = a32 * b00;
- const uint64_t c64 = a32 * b32;
-
- const uint32_t carry =
- static_cast<uint32_t>(((c00 >> 32) + static_cast<uint32_t>(c32a) +
- static_cast<uint32_t>(c32b)) >>
- 32);
-
- return absl::MakeUint128(c64 + (c32a >> 32) + (c32b >> 32) + carry,
- c00 + (c32a << 32) + (c32b << 32));
-#endif
-}
-
-// wide_multiply<T> multiplies two N-bit values to a 2N-bit result.
-template <typename UIntType>
-struct wide_multiply {
- static constexpr size_t kN = std::numeric_limits<UIntType>::digits;
- using input_type = UIntType;
- using result_type = typename random_internal::unsigned_bits<kN * 2>::type;
-
- static result_type multiply(input_type a, input_type b) {
- return static_cast<result_type>(a) * b;
- }
-
- static input_type hi(result_type r) { return r >> kN; }
- static input_type lo(result_type r) { return r; }
-
- static_assert(std::is_unsigned<UIntType>::value,
- "Class-template wide_multiply<> argument must be unsigned.");
-};
-
-#ifndef ABSL_HAVE_INTRINSIC_INT128
-template <>
-struct wide_multiply<uint64_t> {
- using input_type = uint64_t;
- using result_type = uint128;
-
- static result_type multiply(uint64_t a, uint64_t b) {
- return MultiplyU64ToU128(a, b);
- }
-
- static uint64_t hi(result_type r) { return Uint128High64(r); }
- static uint64_t lo(result_type r) { return Uint128Low64(r); }
-};
-#endif
-
} // namespace random_internal
} // namespace absl