third_party/highway/hwy/per_target.h

   1 // Copyright 2022 Google LLC
   2 // SPDX-License-Identifier: Apache-2.0
   3 //
   4 // Licensed under the Apache License, Version 2.0 (the "License");
   5 // you may not use this file except in compliance with the License.
   6 // You may obtain a copy of the License at
   7 //
   8 //      http://www.apache.org/licenses/LICENSE-2.0
   9 //
  10 // Unless required by applicable law or agreed to in writing, software
  11 // distributed under the License is distributed on an "AS IS" BASIS,
  12 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  13 // See the License for the specific language governing permissions and
  14 // limitations under the License.
  15
  16 #ifndef HIGHWAY_HWY_PER_TARGET_H_
  17 #define HIGHWAY_HWY_PER_TARGET_H_
  18
  19 #include <stddef.h>
  20 #include <stdint.h>
  21
  22 #include "hwy/highway_export.h"
  23
  24 // Functions to query the capabilities of the target that will be called by
  25 // HWY_DYNAMIC_DISPATCH, which is not necessarily the current target.
  26
  27 namespace hwy {
  28
  29 // Returns the HWY_TARGET which HWY_DYNAMIC_DISPATCH selected.
  30 HWY_DLLEXPORT int64_t DispatchedTarget();
  31
  32 // Returns size in bytes of a vector, i.e. `Lanes(ScalableTag<uint8_t>())`.
  33 //
  34 // Do not cache the result, which may change after calling DisableTargets, or
  35 // if software requests a different vector size (e.g. when entering/exiting SME
  36 // streaming mode). Instead call this right before the code that depends on the
  37 // result, without any DisableTargets or SME transition in-between. Note that
  38 // this involves an indirect call, so prefer not to call this frequently nor
  39 // unnecessarily.
  40 HWY_DLLEXPORT size_t VectorBytes();
  41
  42 // Returns whether 16/64-bit floats are a supported lane type.
  43 HWY_DLLEXPORT bool HaveFloat16();
  44 HWY_DLLEXPORT bool HaveFloat64();
  45
  46 }  // namespace hwy
  47
  48 #endif  // HIGHWAY_HWY_PER_TARGET_H_