Andrew Scull | 5e1ddfa | 2018-08-14 10:06:54 +0100 | [diff] [blame] | 1 | //===-- llvm/Support/DJB.h ---DJB Hash --------------------------*- C++ -*-===// |
| 2 | // |
Andrew Walbran | 16937d0 | 2019-10-22 13:54:20 +0100 | [diff] [blame] | 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 |
Andrew Scull | 5e1ddfa | 2018-08-14 10:06:54 +0100 | [diff] [blame] | 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 |