1// Copyright 2015 The Gemmlowp Authors. All Rights Reserved. 2// 3// Licensed under the Apache License, Version 2.0 (the "License"); 4// you may not use this file except in compliance with the License. 5// You may obtain a copy of the License at 6// 7// http://www.apache.org/licenses/LICENSE-2.0 8// 9// Unless required by applicable law or agreed to in writing, software 10// distributed under the License is distributed on an "AS IS" BASIS, 11// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 12// See the License for the specific language governing permissions and 13// limitations under the License. 14 15// bit_depth.h: defines the settins controlling LHS/RHS bit depth 16 17#ifndef GEMMLOWP_PUBLIC_BIT_DEPTH_H_ 18#define GEMMLOWP_PUBLIC_BIT_DEPTH_H_ 19 20namespace gemmlowp { 21 22// The range of allowed values for an operand. 23template <int tMinValue, int tMaxValue> 24struct OperandRange { 25 static const int kMinValue = tMinValue; 26 static const int kMaxValue = tMaxValue; 27 static_assert(0 <= kMinValue, ""); 28 static_assert(kMinValue < kMaxValue, ""); 29 static_assert(kMaxValue <= 255, ""); 30}; 31 32using Uint8Range = OperandRange<0, 255>; 33using Uint8RangeExcludingZero = OperandRange<1, 255>; 34 35template <typename tLhsRange, typename tRhsRange> 36struct BitDepthParams { 37 using LhsRange = tLhsRange; 38 using RhsRange = tRhsRange; 39}; 40 41// Default: LHS and RHS are 8bit. 42using DefaultL8R8BitDepthParams = BitDepthParams<Uint8Range, Uint8Range>; 43 44// Variant: LHS may not take the value 0. This allows using 45// faster kernels using signed arithmetic, see 46// NEON_64bit_GEMM_Int8Operands_Int32Accumulators_AccumTwoWithin16Bits 47using L8R8WithLhsNonzeroBitDepthParams = 48 BitDepthParams<Uint8RangeExcludingZero, Uint8Range>; 49 50// Deprecated: when gemmlowp used to allow requantizing 8bit 51// inputs to less-than-8-bit depths, the public setting allowing 52// that was DefaultL7R5BitDepthParams. That requantization 53// feature has been removed, but as the whole point of that 54// requantization was to make less-than-8-bit an internal 55// optimization without any impact on the API (other than lowering 56// accuracy), we can temporarily support users who were using it 57// by mapping it to the default 8bit behavior. 58using DefaultL7R5BitDepthParams = DefaultL8R8BitDepthParams; 59 60} // namespace gemmlowp 61 62#endif // GEMMLOWP_PUBLIC_BIT_DEPTH_H_ 63