1 //===- llvm/Transforms/Utils/IntegerDivision.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 contains an implementation of 32bit and 64bit scalar integer 10 // division for targets that don't have native support. It's largely derived 11 // from compiler-rt's implementations of __udivsi3 and __udivmoddi4, 12 // but hand-tuned for targets that prefer less control flow. 13 // 14 //===----------------------------------------------------------------------===// 15 16 #ifndef LLVM_TRANSFORMS_UTILS_INTEGERDIVISION_H 17 #define LLVM_TRANSFORMS_UTILS_INTEGERDIVISION_H 18 19 namespace llvm { 20 class BinaryOperator; 21 } 22 23 namespace llvm { 24 25 /// Generate code to calculate the remainder of two integers, replacing Rem 26 /// with the generated code. This currently generates code using the udiv 27 /// expansion, but future work includes generating more specialized code, 28 /// e.g. when more information about the operands are known. Implements both 29 /// 32bit and 64bit scalar division. 30 /// 31 /// Replace Rem with generated code. 32 bool expandRemainder(BinaryOperator *Rem); 33 34 /// Generate code to divide two integers, replacing Div with the generated 35 /// code. This currently generates code similarly to compiler-rt's 36 /// implementations, but future work includes generating more specialized code 37 /// when more information about the operands are known. Implements both 38 /// 32bit and 64bit scalar division. 39 /// 40 /// Replace Div with generated code. 41 bool expandDivision(BinaryOperator* Div); 42 43 /// Generate code to calculate the remainder of two integers, replacing Rem 44 /// with the generated code. Uses ExpandReminder with a 32bit Rem which 45 /// makes it useful for targets with little or no support for less than 46 /// 32 bit arithmetic. 47 /// 48 /// Replace Rem with generated code. 49 bool expandRemainderUpTo32Bits(BinaryOperator *Rem); 50 51 /// Generate code to calculate the remainder of two integers, replacing Rem 52 /// with the generated code. Uses ExpandReminder with a 64bit Rem. 53 /// 54 /// Replace Rem with generated code. 55 bool expandRemainderUpTo64Bits(BinaryOperator *Rem); 56 57 /// Generate code to divide two integers, replacing Div with the generated 58 /// code. Uses ExpandDivision with a 32bit Div which makes it useful for 59 /// targets with little or no support for less than 32 bit arithmetic. 60 /// 61 /// Replace Rem with generated code. 62 bool expandDivisionUpTo32Bits(BinaryOperator *Div); 63 64 /// Generate code to divide two integers, replacing Div with the generated 65 /// code. Uses ExpandDivision with a 64bit Div. 66 /// 67 /// Replace Rem with generated code. 68 bool expandDivisionUpTo64Bits(BinaryOperator *Div); 69 70 } // End llvm namespace 71 72 #endif 73