LLVM  10.0.0svn
BasicGOTAndStubsBuilder.h
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1 //===--- BasicGOTAndStubsBuilder.h - Generic GOT/Stub creation --*- 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 // A base for simple GOT and stub creation.
10 //
11 //===----------------------------------------------------------------------===//
12 
13 #ifndef LLVM_LIB_EXECUTIONENGINE_JITLINK_BASICGOTANDSTUBSBUILDER_H
14 #define LLVM_LIB_EXECUTIONENGINE_JITLINK_BASICGOTANDSTUBSBUILDER_H
15 
17 
18 namespace llvm {
19 namespace jitlink {
20 
21 template <typename BuilderImpl> class BasicGOTAndStubsBuilder {
22 public:
24 
25  void run() {
26  // We're going to be adding new blocks, but we don't want to iterate over
27  // the newly added ones, so just copy the existing blocks out.
28  std::vector<Block *> Blocks(G.blocks().begin(), G.blocks().end());
29 
30  for (auto *B : Blocks)
31  for (auto &E : B->edges())
32  if (impl().isGOTEdge(E))
33  impl().fixGOTEdge(E, getGOTEntrySymbol(E.getTarget()));
34  else if (impl().isExternalBranchEdge(E))
35  impl().fixExternalBranchEdge(E, getStubSymbol(E.getTarget()));
36  }
37 
38 protected:
40  assert(Target.hasName() && "GOT edge cannot point to anonymous target");
41 
42  auto GOTEntryI = GOTEntries.find(Target.getName());
43 
44  // Build the entry if it doesn't exist.
45  if (GOTEntryI == GOTEntries.end()) {
46  auto &GOTEntry = impl().createGOTEntry(Target);
47  GOTEntryI =
48  GOTEntries.insert(std::make_pair(Target.getName(), &GOTEntry)).first;
49  }
50 
51  assert(GOTEntryI != GOTEntries.end() && "Could not get GOT entry symbol");
52  return *GOTEntryI->second;
53  }
54 
56  assert(Target.hasName() &&
57  "External branch edge can not point to an anonymous target");
58  auto StubI = Stubs.find(Target.getName());
59 
60  if (StubI == Stubs.end()) {
61  auto &StubSymbol = impl().createStub(Target);
62  StubI = Stubs.insert(std::make_pair(Target.getName(), &StubSymbol)).first;
63  }
64 
65  assert(StubI != Stubs.end() && "Count not get stub symbol");
66  return *StubI->second;
67  }
68 
70 
71 private:
72  BuilderImpl &impl() { return static_cast<BuilderImpl &>(*this); }
73 
76 };
77 
78 } // end namespace jitlink
79 } // end namespace llvm
80 
81 #endif // LLVM_LIB_EXECUTIONENGINE_JITLINK_BASICGOTANDSTUBSBUILDER_H
This class represents lattice values for constants.
Definition: AllocatorList.h:23
static GCRegistry::Add< OcamlGC > B("ocaml", "ocaml 3.10-compatible GC")
static GCRegistry::Add< CoreCLRGC > E("coreclr", "CoreCLR-compatible GC")
Target - Wrapper for Target specific information.
assert(ImpDefSCC.getReg()==AMDGPU::SCC &&ImpDefSCC.isDef())