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
13#include "llvm/IR/ValueSymbolTable.h"
14#include "llvm/ADT/SmallString.h"
15#include "llvm/Config/llvm-config.h"
16#include "llvm/IR/GlobalValue.h"
17#include "llvm/IR/Module.h"
18#include "llvm/IR/Type.h"
19#include "llvm/IR/Value.h"
20#include "llvm/Support/Casting.h"
21#include "llvm/Support/Compiler.h"
22#include "llvm/Support/Debug.h"
23#include "llvm/Support/raw_ostream.h"
24#include "llvm/TargetParser/Triple.h"
25#include <cassert>
26#include <utility>
27
28using namespace llvm;
29
30#define DEBUG_TYPE "valuesymtab"
31
32// Class destructor
33ValueSymbolTable::~ValueSymbolTable() {
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
43ValueName *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(N: BaseSize);
49 raw_svector_ostream S(UniqueName);
50 if (auto *GV = dyn_cast<GlobalValue>(Val: 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(KV: std::make_pair(x: UniqueName.str(), y&: 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//
72void 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(KeyValue: 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 MallocAllocator Allocator;
87 V->getValueName()->Destroy(allocator&: Allocator);
88
89 ValueName *VN = makeUniqueName(V, UniqueName);
90 V->setValueName(VN);
91}
92
93void ValueSymbolTable::removeValueName(ValueName *V) {
94 // LLVM_DEBUG(dbgs() << " Removing Value: " << V->getKeyData() << "\n");
95 // Remove the value from the symbol table.
96 vmap.remove(KeyValue: V);
97}
98
99/// createValueName - This method attempts to create a value name and insert
100/// it into the symbol table with the specified name. If it conflicts, it
101/// auto-renames the name and returns that instead.
102ValueName *ValueSymbolTable::createValueName(StringRef Name, Value *V) {
103 if (MaxNameSize > -1 && Name.size() > (unsigned)MaxNameSize)
104 Name = Name.substr(Start: 0, N: std::max(a: 1u, b: (unsigned)MaxNameSize));
105
106 // In the common case, the name is not already in the symbol table.
107 auto IterBool = vmap.insert(KV: std::make_pair(x&: Name, y&: V));
108 if (IterBool.second) {
109 // LLVM_DEBUG(dbgs() << " Inserted value: " << Entry.getKeyData() << ": "
110 // << *V << "\n");
111 return &*IterBool.first;
112 }
113
114 // Otherwise, there is a naming conflict. Rename this value.
115 SmallString<256> UniqueName(Name.begin(), Name.end());
116 return makeUniqueName(V, UniqueName);
117}
118
119#if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
120// dump - print out the symbol table
121//
122LLVM_DUMP_METHOD void ValueSymbolTable::dump() const {
123 // dbgs() << "ValueSymbolTable:\n";
124 for (const auto &I : *this) {
125 // dbgs() << " '" << I->getKeyData() << "' = ";
126 I.getValue()->dump();
127 // dbgs() << "\n";
128 }
129}
130#endif
131

source code of llvm/lib/IR/ValueSymbolTable.cpp