1 //===- llvm/Transforms/Utils/IntegerDivision.h ------------------*- C++ -*-===// 2 // 3 // The LLVM Compiler Infrastructure 4 // 5 // This file is distributed under the University of Illinois Open Source 6 // License. See LICENSE.TXT for details. 7 // 8 //===----------------------------------------------------------------------===// 9 // 10 // This file contains an implementation of 32bit integer division for targets 11 // that don't have native support. It's largely derived from compiler-rt's 12 // implementation of __udivsi3, but hand-tuned for targets that prefer less 13 // control flow. 14 // 15 //===----------------------------------------------------------------------===// 16 17 #ifndef LLVM_TRANSFORMS_UTILS_INTEGERDIVISION_H 18 #define LLVM_TRANSFORMS_UTILS_INTEGERDIVISION_H 19 20 namespace llvm { 21 class BinaryOperator; 22 } 23 24 namespace llvm { 25 26 /// Generate code to calculate the remainder of two integers, replacing Rem 27 /// with the generated code. This currently generates code using the udiv 28 /// expansion, but future work includes generating more specialized code, 29 /// e.g. when more information about the operands are known. Currently only 30 /// implements 32bit scalar division (due to udiv's limitation), but future 31 /// work is removing this limitation. 32 /// 33 /// @brief Replace Rem with generated code. 34 bool expandRemainder(BinaryOperator *Rem); 35 36 /// Generate code to divide two integers, replacing Div with the generated 37 /// code. This currently generates code similarly to compiler-rt's 38 /// implementations, but future work includes generating more specialized code 39 /// when more information about the operands are known. Currently only 40 /// implements 32bit scalar division, but future work is removing this 41 /// limitation. 42 /// 43 /// @brief Replace Div with generated code. 44 bool expandDivision(BinaryOperator* Div); 45 46 /// Generate code to calculate the remainder of two integers, replacing Rem 47 /// with the generated code. Uses the above 32bit routine, therefore adequate 48 /// for targets with little or no support for less than 32 bit arithmetic. 49 /// 50 /// @brief Replace Rem with generated code. 51 bool expandRemainderUpTo32Bits(BinaryOperator *Rem); 52 53 /// Generate code to divide two integers, replacing Div with the generated 54 /// code. Uses the above 32bit routine, therefore adequate for targets with 55 /// little or no support for less than 32 bit arithmetic. 56 /// 57 /// @brief Replace Rem with generated code. 58 bool expandDivisionUpTo32Bits(BinaryOperator *Div); 59 60 } // End llvm namespace 61 62 #endif 63
