LLVM  10.0.0svn
ValueSymbolTable.cpp
Go to the documentation of this file.
1 //===- ValueSymbolTable.cpp - Implement the ValueSymbolTable class --------===//
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 implements the ValueSymbolTable class for the IR library.
10 //
11 //===----------------------------------------------------------------------===//
12 
14 #include "llvm/ADT/SmallString.h"
15 #include "llvm/ADT/Triple.h"
16 #include "llvm/Config/llvm-config.h"
17 #include "llvm/IR/GlobalValue.h"
18 #include "llvm/IR/Module.h"
19 #include "llvm/IR/Type.h"
20 #include "llvm/IR/Value.h"
21 #include "llvm/Support/Casting.h"
22 #include "llvm/Support/Compiler.h"
23 #include "llvm/Support/Debug.h"
25 #include <cassert>
26 #include <utility>
27 
28 using namespace llvm;
29 
30 #define DEBUG_TYPE "valuesymtab"
31 
32 // Class destructor
34 #ifndef NDEBUG // Only do this in -g mode...
35  for (const auto &VI : vmap)
36  dbgs() << "Value still in symbol table! Type = '"
37  << *VI.getValue()->getType() << "' Name = '" << VI.getKeyData()
38  << "'\n";
39  assert(vmap.empty() && "Values remain in symbol table!");
40 #endif
41 }
42 
43 ValueName *ValueSymbolTable::makeUniqueName(Value *V,
44  SmallString<256> &UniqueName) {
45  unsigned BaseSize = UniqueName.size();
46  while (true) {
47  // Trim any suffix off and append the next number.
48  UniqueName.resize(BaseSize);
49  raw_svector_ostream S(UniqueName);
50  if (auto *GV = dyn_cast<GlobalValue>(V)) {
51  // A dot is appended to mark it as clone during ABI demangling so that
52  // for example "_Z1fv" and "_Z1fv.1" both demangle to "f()", the second
53  // one being a clone.
54  // On NVPTX we cannot use a dot because PTX only allows [A-Za-z0-9_$] for
55  // identifiers. This breaks ABI demangling but at least ptxas accepts and
56  // compiles the program.
57  const Module *M = GV->getParent();
58  if (!(M && Triple(M->getTargetTriple()).isNVPTX()))
59  S << ".";
60  }
61  S << ++LastUnique;
62 
63  // Try insert the vmap entry with this suffix.
64  auto IterBool = vmap.insert(std::make_pair(UniqueName, V));
65  if (IterBool.second)
66  return &*IterBool.first;
67  }
68 }
69 
70 // Insert a value into the symbol table with the specified name...
71 //
72 void ValueSymbolTable::reinsertValue(Value* V) {
73  assert(V->hasName() && "Can't insert nameless Value into symbol table");
74 
75  // Try inserting the name, assuming it won't conflict.
76  if (vmap.insert(V->getValueName())) {
77  // LLVM_DEBUG(dbgs() << " Inserted value: " << V->getValueName() << ": " <<
78  // *V << "\n");
79  return;
80  }
81 
82  // Otherwise, there is a naming conflict. Rename this value.
83  SmallString<256> UniqueName(V->getName().begin(), V->getName().end());
84 
85  // The name is too already used, just free it so we can allocate a new name.
86  V->getValueName()->Destroy();
87 
88  ValueName *VN = makeUniqueName(V, UniqueName);
89  V->setValueName(VN);
90 }
91 
92 void ValueSymbolTable::removeValueName(ValueName *V) {
93  // LLVM_DEBUG(dbgs() << " Removing Value: " << V->getKeyData() << "\n");
94  // Remove the value from the symbol table.
95  vmap.remove(V);
96 }
97 
98 /// createValueName - This method attempts to create a value name and insert
99 /// it into the symbol table with the specified name. If it conflicts, it
100 /// auto-renames the name and returns that instead.
101 ValueName *ValueSymbolTable::createValueName(StringRef Name, Value *V) {
102  // In the common case, the name is not already in the symbol table.
103  auto IterBool = vmap.insert(std::make_pair(Name, V));
104  if (IterBool.second) {
105  // LLVM_DEBUG(dbgs() << " Inserted value: " << Entry.getKeyData() << ": "
106  // << *V << "\n");
107  return &*IterBool.first;
108  }
109 
110  // Otherwise, there is a naming conflict. Rename this value.
111  SmallString<256> UniqueName(Name.begin(), Name.end());
112  return makeUniqueName(V, UniqueName);
113 }
114 
115 #if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
116 // dump - print out the symbol table
117 //
119  //dbgs() << "ValueSymbolTable:\n";
120  for (const auto &I : *this) {
121  //dbgs() << " '" << I->getKeyData() << "' = ";
122  I.getValue()->dump();
123  //dbgs() << "\n";
124  }
125 }
126 #endif
const std::string & getTargetTriple() const
Get the target triple which is a string describing the target host.
Definition: Module.h:241
This class represents lattice values for constants.
Definition: AllocatorList.h:23
#define LLVM_DUMP_METHOD
Mark debug helper function definitions like dump() that should not be stripped from debug builds...
Definition: Compiler.h:484
StringMapEntry - This is used to represent one value that is inserted into a StringMap.
Definition: StringMap.h:158
void remove(MapEntryTy *KeyValue)
remove - Remove the specified key/value pair from the map, but do not erase it.
Definition: StringMap.h:469
A Module instance is used to store all the information related to an LLVM module. ...
Definition: Module.h:66
amdgpu Simplify well known AMD library false FunctionCallee Value const Twine & Name
A raw_ostream that writes to an SmallVector or SmallString.
Definition: raw_ostream.h:530
void Destroy(AllocatorTy &Allocator)
Destroy - Destroy this StringMapEntry, releasing memory back to the specified allocator.
Definition: StringMap.h:223
bool hasName() const
Definition: Value.h:252
size_t size() const
Definition: SmallVector.h:52
Triple - Helper class for working with autoconf configuration names.
Definition: Triple.h:43
Module.h This file contains the declarations for the Module class.
ValueName * getValueName() const
Definition: Value.cpp:186
bool insert(MapEntryTy *KeyValue)
insert - Insert the specified key/value pair into the map.
Definition: StringMap.h:393
raw_ostream & dbgs()
dbgs() - This returns a reference to a raw_ostream for debugging messages.
Definition: Debug.cpp:132
iterator begin() const
Definition: StringRef.h:115
StringRef getName() const
Return a constant reference to the value&#39;s name.
Definition: Value.cpp:214
#define I(x, y, z)
Definition: MD5.cpp:58
void dump() const
This function can be used from the debugger to display the content of the symbol table while debuggin...
assert(ImpDefSCC.getReg()==AMDGPU::SCC &&ImpDefSCC.isDef())
LLVM Value Representation.
Definition: Value.h:74
void setValueName(ValueName *VN)
Definition: Value.cpp:197
StringRef - Represent a constant reference to a string, i.e.
Definition: StringRef.h:48
iterator end() const
Definition: StringRef.h:117
void resize(size_type N)
Definition: SmallVector.h:344