1 //===- llvm/Support/DivisionByConstantInfo.h ---------------------*- C++ -*-==// 2 // 3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4 // See https://llvm.org/LICENSE.txt for license information. 5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6 // 7 //===----------------------------------------------------------------------===// 8 /// 9 /// This file implements support for optimizing divisions by a constant 10 /// 11 //===----------------------------------------------------------------------===// 12 13 #ifndef LLVM_SUPPORT_DIVISIONBYCONSTANTINFO_H 14 #define LLVM_SUPPORT_DIVISIONBYCONSTANTINFO_H 15 16 #include "llvm/ADT/APInt.h" 17 18 namespace llvm { 19 20 /// Magic data for optimising signed division by a constant. 21 struct SignedDivisionByConstantInfo { 22 static SignedDivisionByConstantInfo get(const APInt &D); 23 APInt Magic; ///< magic number 24 unsigned ShiftAmount; ///< shift amount 25 }; 26 27 /// Magic data for optimising unsigned division by a constant. 28 struct UnsignedDivisionByConstantInfo { 29 static UnsignedDivisionByConstantInfo 30 get(const APInt &D, unsigned LeadingZeros = 0, 31 bool AllowEvenDivisorOptimization = true); 32 APInt Magic; ///< magic number 33 bool IsAdd; ///< add indicator 34 unsigned PostShift; ///< post-shift amount 35 unsigned PreShift; ///< pre-shift amount 36 }; 37 38 } // namespace llvm 39 40 #endif 41