1 //===- unittests/Lex/HeaderMapTestUtils.h - HeaderMap utils -------===//
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 #ifndef LLVM_CLANG_UNITTESTS_LEX_HEADERMAPTESTUTILS_H
10 #define LLVM_CLANG_UNITTESTS_LEX_HEADERMAPTESTUTILS_H
11 
12 #include "clang/Basic/CharInfo.h"
13 #include "clang/Lex/HeaderMap.h"
14 #include "clang/Lex/HeaderMapTypes.h"
15 #include "llvm/Support/SwapByteOrder.h"
16 #include <cassert>
17 
18 namespace clang {
19 namespace test {
20 
21 // Lay out a header file for testing.
22 template <unsigned NumBuckets, unsigned NumBytes> struct HMapFileMock {
23   HMapHeader Header;
24   HMapBucket Buckets[NumBuckets];
25   unsigned char Bytes[NumBytes];
26 
initHMapFileMock27   void init() {
28     memset(this, 0, sizeof(HMapFileMock));
29     Header.Magic = HMAP_HeaderMagicNumber;
30     Header.Version = HMAP_HeaderVersion;
31     Header.NumBuckets = NumBuckets;
32     Header.StringsOffset = sizeof(Header) + sizeof(Buckets);
33   }
34 
swapBytesHMapFileMock35   void swapBytes() {
36     using llvm::sys::getSwappedBytes;
37     Header.Magic = getSwappedBytes(Header.Magic);
38     Header.Version = getSwappedBytes(Header.Version);
39     Header.NumBuckets = getSwappedBytes(Header.NumBuckets);
40     Header.StringsOffset = getSwappedBytes(Header.StringsOffset);
41   }
42 
getBufferHMapFileMock43   std::unique_ptr<llvm::MemoryBuffer> getBuffer() {
44     return llvm::MemoryBuffer::getMemBuffer(
45         StringRef(reinterpret_cast<char *>(this), sizeof(HMapFileMock)),
46         "header",
47         /* RequresNullTerminator */ false);
48   }
49 };
50 
51 template <class FileTy> struct HMapFileMockMaker {
52   FileTy &File;
53   unsigned SI = 1;
54   unsigned BI = 0;
HMapFileMockMakerHMapFileMockMaker55   HMapFileMockMaker(FileTy &File) : File(File) {}
56 
addStringHMapFileMockMaker57   unsigned addString(StringRef S) {
58     assert(SI + S.size() + 1 <= sizeof(File.Bytes));
59     std::copy(S.begin(), S.end(), File.Bytes + SI);
60     auto OldSI = SI;
61     SI += S.size() + 1;
62     return OldSI;
63   }
64 
addBucketHMapFileMockMaker65   void addBucket(StringRef Str, unsigned Key, unsigned Prefix,
66                  unsigned Suffix) {
67     addBucket(getHash(Str), Key, Prefix, Suffix);
68   }
69 
addBucketHMapFileMockMaker70   void addBucket(unsigned Hash, unsigned Key, unsigned Prefix,
71                  unsigned Suffix) {
72     assert(!(File.Header.NumBuckets & (File.Header.NumBuckets - 1)));
73     unsigned I = Hash & (File.Header.NumBuckets - 1);
74     do {
75       if (!File.Buckets[I].Key) {
76         File.Buckets[I].Key = Key;
77         File.Buckets[I].Prefix = Prefix;
78         File.Buckets[I].Suffix = Suffix;
79         ++File.Header.NumEntries;
80         return;
81       }
82       ++I;
83       I &= File.Header.NumBuckets - 1;
84     } while (I != (Hash & (File.Header.NumBuckets - 1)));
85     llvm_unreachable("no empty buckets");
86   }
87 
88   // The header map hash function.
getHashHMapFileMockMaker89   static unsigned getHash(StringRef Str) {
90     unsigned Result = 0;
91     for (char C : Str)
92       Result += toLowercase(C) * 13;
93     return Result;
94   }
95 };
96 
97 } // namespace test
98 } // namespace clang
99 
100 #endif
101