LLVM  10.0.0svn
StringToOffsetTable.h
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1 //===- StringToOffsetTable.h - Emit a big concatenated string ---*- 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 #ifndef LLVM_TABLEGEN_STRINGTOOFFSETTABLE_H
10 #define LLVM_TABLEGEN_STRINGTOOFFSETTABLE_H
11 
12 #include "llvm/ADT/SmallString.h"
13 #include "llvm/ADT/StringExtras.h"
14 #include "llvm/ADT/StringMap.h"
16 #include <cctype>
17 
18 namespace llvm {
19 
20 /// StringToOffsetTable - This class uniques a bunch of nul-terminated strings
21 /// and keeps track of their offset in a massive contiguous string allocation.
22 /// It can then output this string blob and use indexes into the string to
23 /// reference each piece.
25  StringMap<unsigned> StringOffset;
26  std::string AggregateString;
27 
28 public:
29  bool Empty() const { return StringOffset.empty(); }
30 
31  unsigned GetOrAddStringOffset(StringRef Str, bool appendZero = true) {
32  auto IterBool =
33  StringOffset.insert(std::make_pair(Str, AggregateString.size()));
34  if (IterBool.second) {
35  // Add the string to the aggregate if this is the first time found.
36  AggregateString.append(Str.begin(), Str.end());
37  if (appendZero)
38  AggregateString += '\0';
39  }
40 
41  return IterBool.first->second;
42  }
43 
45  // Escape the string.
46  SmallString<256> Str;
47  raw_svector_ostream(Str).write_escaped(AggregateString);
48  AggregateString = Str.str();
49 
50  O << " \"";
51  unsigned CharsPrinted = 0;
52  for (unsigned i = 0, e = AggregateString.size(); i != e; ++i) {
53  if (CharsPrinted > 70) {
54  O << "\"\n \"";
55  CharsPrinted = 0;
56  }
57  O << AggregateString[i];
58  ++CharsPrinted;
59 
60  // Print escape sequences all together.
61  if (AggregateString[i] != '\\')
62  continue;
63 
64  assert(i + 1 < AggregateString.size() && "Incomplete escape sequence!");
65  if (isdigit(AggregateString[i + 1])) {
66  assert(isdigit(AggregateString[i + 2]) &&
67  isdigit(AggregateString[i + 3]) &&
68  "Expected 3 digit octal escape!");
69  O << AggregateString[++i];
70  O << AggregateString[++i];
71  O << AggregateString[++i];
72  CharsPrinted += 3;
73  } else {
74  O << AggregateString[++i];
75  ++CharsPrinted;
76  }
77  }
78  O << "\"";
79  }
80 
81  /// Emit the string using character literals. MSVC has a limitation that
82  /// string literals cannot be longer than 64K.
84  assert(AggregateString.find(')') == std::string::npos &&
85  "can't emit raw string with closing parens");
86  int Count = 0;
87  O << ' ';
88  for (char C : AggregateString) {
89  O << " \'";
90  O.write_escaped(StringRef(&C, 1));
91  O << "\',";
92  Count++;
93  if (Count > 14) {
94  O << "\n ";
95  Count = 0;
96  }
97  }
98  O << '\n';
99  }
100 };
101 
102 } // end namespace llvm
103 
104 #endif
uint64_t CallInst * C
This class represents lattice values for constants.
Definition: AllocatorList.h:23
A raw_ostream that writes to an SmallVector or SmallString.
Definition: raw_ostream.h:530
unsigned GetOrAddStringOffset(StringRef Str, bool appendZero=true)
StringToOffsetTable - This class uniques a bunch of nul-terminated strings and keeps track of their o...
StringRef str() const
Explicit conversion to StringRef.
Definition: SmallString.h:266
LLVM_NODISCARD size_t size() const
size - Get the string size.
Definition: StringRef.h:144
void EmitString(raw_ostream &O)
constexpr double e
Definition: MathExtras.h:57
raw_ostream & write_escaped(StringRef Str, bool UseHexEscapes=false)
Output Str, turning &#39;\&#39;, &#39;&#39;, &#39; &#39;, &#39;"&#39;, and anything that doesn&#39;t satisfy llvm::isPrint into an escape...
bool insert(MapEntryTy *KeyValue)
insert - Insert the specified key/value pair into the map.
Definition: StringMap.h:393
iterator begin() const
Definition: StringRef.h:115
bool empty() const
Definition: StringMap.h:110
assert(ImpDefSCC.getReg()==AMDGPU::SCC &&ImpDefSCC.isDef())
void EmitCharArray(raw_ostream &O)
Emit the string using character literals.
This class implements an extremely fast bulk output stream that can only output to a stream...
Definition: raw_ostream.h:45
StringRef - Represent a constant reference to a string, i.e.
Definition: StringRef.h:48
iterator end() const
Definition: StringRef.h:117