1//===----------- Mangling.cpp -- Name Mangling Utilities for ORC ----------===//
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#include "llvm/ExecutionEngine/Orc/Mangling.h"
10#include "llvm/IR/Constants.h"
11#include "llvm/IR/Mangler.h"
12#include "llvm/Support/Debug.h"
13
14#define DEBUG_TYPE "orc"
15
16namespace llvm {
17namespace orc {
18
19MangleAndInterner::MangleAndInterner(ExecutionSession &ES, const DataLayout &DL)
20    : ES(ES), DL(DL) {}
21
22SymbolStringPtr MangleAndInterner::operator()(StringRef Name) {
23  std::string MangledName;
24  {
25    raw_string_ostream MangledNameStream(MangledName);
26    Mangler::getNameWithPrefix(MangledNameStream, Name, DL);
27  }
28  return ES.intern(MangledName);
29}
30
31void IRSymbolMapper::add(ExecutionSession &ES, const ManglingOptions &MO,
32                         ArrayRef<GlobalValue *> GVs,
33                         SymbolFlagsMap &SymbolFlags,
34                         SymbolNameToDefinitionMap *SymbolToDefinition) {
35  if (GVs.empty())
36    return;
37
38  MangleAndInterner Mangle(ES, GVs[0]->getParent()->getDataLayout());
39  for (auto *G : GVs) {
40    assert(G && "GVs cannot contain null elements");
41    if (!G->hasName() || G->isDeclaration() || G->hasLocalLinkage() ||
42        G->hasAvailableExternallyLinkage() || G->hasAppendingLinkage())
43      continue;
44
45    if (G->isThreadLocal() && MO.EmulatedTLS) {
46      auto *GV = cast<GlobalVariable>(G);
47
48      auto Flags = JITSymbolFlags::fromGlobalValue(*GV);
49
50      auto EmuTLSV = Mangle(("__emutls_v." + GV->getName()).str());
51      SymbolFlags[EmuTLSV] = Flags;
52      if (SymbolToDefinition)
53        (*SymbolToDefinition)[EmuTLSV] = GV;
54
55      // If this GV has a non-zero initializer we'll need to emit an
56      // __emutls.t symbol too.
57      if (GV->hasInitializer()) {
58        const auto *InitVal = GV->getInitializer();
59
60        // Skip zero-initializers.
61        if (isa<ConstantAggregateZero>(InitVal))
62          continue;
63        const auto *InitIntValue = dyn_cast<ConstantInt>(InitVal);
64        if (InitIntValue && InitIntValue->isZero())
65          continue;
66
67        auto EmuTLST = Mangle(("__emutls_t." + GV->getName()).str());
68        SymbolFlags[EmuTLST] = Flags;
69        if (SymbolToDefinition)
70          (*SymbolToDefinition)[EmuTLST] = GV;
71      }
72      continue;
73    }
74
75    // Otherwise we just need a normal linker mangling.
76    auto MangledName = Mangle(G->getName());
77    SymbolFlags[MangledName] = JITSymbolFlags::fromGlobalValue(*G);
78    if (SymbolToDefinition)
79      (*SymbolToDefinition)[MangledName] = G;
80  }
81}
82
83} // End namespace orc.
84} // End namespace llvm.
85