LLVM  9.0.0svn
DJB.h
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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.
30 } // namespace llvm
31 
32 #endif // LLVM_SUPPORT_DJB_H
uint64_t CallInst * C
This class represents lattice values for constants.
Definition: AllocatorList.h:23
iterator_range< const unsigned char * > bytes() const
Definition: StringRef.h:111
#define H(x, y, z)
Definition: MD5.cpp:57
uint32_t djbHash(StringRef Buffer, uint32_t H=5381)
The Bernstein hash function used by the DWARF accelerator tables.
Definition: DJB.h:21
uint32_t caseFoldingDjbHash(StringRef Buffer, uint32_t H=5381)
Computes the Bernstein hash after folding the input according to the Dwarf 5 standard case folding ru...
Definition: DJB.cpp:70
StringRef - Represent a constant reference to a string, i.e.
Definition: StringRef.h:48