1 //===------ DumpFunctionPass.cpp --------------------------------*- 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 // Write a function to a file.
10 //
11 //===----------------------------------------------------------------------===//
12
13 #include "polly/Support/DumpFunctionPass.h"
14 #include "llvm/IR/Module.h"
15 #include "llvm/Pass.h"
16 #include "llvm/Support/Debug.h"
17 #include "llvm/Support/FileSystem.h"
18 #include "llvm/Support/Path.h"
19 #include "llvm/Support/ToolOutputFile.h"
20 #include "llvm/Transforms/IPO/GlobalDCE.h"
21 #include "llvm/Transforms/IPO/StripDeadPrototypes.h"
22 #include "llvm/Transforms/Utils/Cloning.h"
23
24 #define DEBUG_TYPE "polly-dump-func"
25
26 using namespace llvm;
27 using namespace polly;
28
29 namespace {
30
runDumpFunction(llvm::Function & F,StringRef Suffix)31 static void runDumpFunction(llvm::Function &F, StringRef Suffix) {
32 StringRef FName = F.getName();
33 Module *M = F.getParent();
34
35 StringRef ModuleName = M->getName();
36 StringRef Stem = sys::path::stem(ModuleName);
37 std::string Dumpfile = (Twine(Stem) + "-" + FName + Suffix + ".ll").str();
38 LLVM_DEBUG(dbgs() << "Dumping function '" << FName << "' to '" << Dumpfile
39 << "'...\n");
40
41 ValueToValueMapTy VMap;
42 auto ShouldCloneDefinition = [&F](const GlobalValue *GV) -> bool {
43 return GV == &F;
44 };
45 std::unique_ptr<Module> CM = CloneModule(*M, VMap, ShouldCloneDefinition);
46 Function *NewF = cast<Function>(VMap.lookup(&F));
47 assert(NewF && "Expected selected function to be cloned");
48
49 LLVM_DEBUG(dbgs() << "Global DCE...\n");
50
51 // Stop F itself from being pruned
52 GlobalValue::LinkageTypes OrigLinkage = NewF->getLinkage();
53 NewF->setLinkage(GlobalValue::ExternalLinkage);
54
55 {
56 ModuleAnalysisManager MAM;
57 ModulePassManager MPM;
58
59 PassInstrumentationCallbacks PIC;
60 MAM.registerPass([&] { return PassInstrumentationAnalysis(&PIC); });
61
62 MPM.addPass(GlobalDCEPass());
63 MPM.addPass(StripDeadPrototypesPass());
64 MPM.run(*CM, MAM);
65 }
66
67 // Restore old linkage
68 NewF->setLinkage(OrigLinkage);
69
70 LLVM_DEBUG(dbgs() << "Write to file '" << Dumpfile << "'...\n");
71
72 std::unique_ptr<ToolOutputFile> Out;
73 std::error_code EC;
74 Out.reset(new ToolOutputFile(Dumpfile, EC, sys::fs::OF_None));
75 if (EC) {
76 errs() << EC.message() << '\n';
77 return;
78 }
79
80 CM->print(Out->os(), nullptr);
81 Out->keep();
82 LLVM_DEBUG(dbgs() << "Dump file " << Dumpfile << " written successfully\n");
83 }
84
85 class DumpFunctionWrapperPass final : public FunctionPass {
86 private:
87 DumpFunctionWrapperPass(const DumpFunctionWrapperPass &) = delete;
88 const DumpFunctionWrapperPass &
89 operator=(const DumpFunctionWrapperPass &) = delete;
90
91 std::string Suffix;
92
93 public:
94 static char ID;
95
DumpFunctionWrapperPass()96 explicit DumpFunctionWrapperPass() : FunctionPass(ID), Suffix("-dump") {}
97
DumpFunctionWrapperPass(std::string Suffix)98 explicit DumpFunctionWrapperPass(std::string Suffix)
99 : FunctionPass(ID), Suffix(std::move(Suffix)) {}
100
101 /// @name FunctionPass interface
102 //@{
getAnalysisUsage(llvm::AnalysisUsage & AU) const103 void getAnalysisUsage(llvm::AnalysisUsage &AU) const override {
104 AU.setPreservesAll();
105 }
106
runOnFunction(llvm::Function & F)107 bool runOnFunction(llvm::Function &F) override {
108 runDumpFunction(F, Suffix);
109 return false;
110 }
111 //@}
112 };
113
114 char DumpFunctionWrapperPass::ID;
115 } // namespace
116
createDumpFunctionWrapperPass(std::string Suffix)117 FunctionPass *polly::createDumpFunctionWrapperPass(std::string Suffix) {
118 return new DumpFunctionWrapperPass(std::move(Suffix));
119 }
120
run(Function & F,FunctionAnalysisManager & AM)121 llvm::PreservedAnalyses DumpFunctionPass::run(Function &F,
122 FunctionAnalysisManager &AM) {
123 runDumpFunction(F, Suffix);
124 return PreservedAnalyses::all();
125 }
126
127 INITIALIZE_PASS_BEGIN(DumpFunctionWrapperPass, "polly-dump-function",
128 "Polly - Dump Function", false, false)
129 INITIALIZE_PASS_END(DumpFunctionWrapperPass, "polly-dump-function",
130 "Polly - Dump Function", false, false)
131