1 //===-- llvm/Support/DJB.h ---DJB Hash --------------------------*- 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 support for the DJ Bernstein hash function. 10 // 11 //===----------------------------------------------------------------------===// 12 13 #ifndef LLVM_SUPPORT_DJB_H 14 #define LLVM_SUPPORT_DJB_H 15 16 #include "llvm/ADT/StringRef.h" 17 18 namespace llvm { 19 20 /// The Bernstein hash function used by the DWARF accelerator tables. 21 inline uint32_t djbHash(StringRef Buffer, uint32_t H = 5381) { 22 for (unsigned char C : Buffer.bytes()) 23 H = (H << 5) + H + C; 24 return H; 25 } 26 27 /// Computes the Bernstein hash after folding the input according to the Dwarf 5 28 /// standard case folding rules. 29 uint32_t caseFoldingDjbHash(StringRef Buffer, uint32_t H = 5381); 30 } // namespace llvm 31 32 #endif // LLVM_SUPPORT_DJB_H 33