1 //===- CodegenCleanup.cpp -------------------------------------------------===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 
10 #include "polly/CodeGen/CodegenCleanup.h"
11 
12 #include "llvm/Analysis/ScopedNoAliasAA.h"
13 #include "llvm/Analysis/TypeBasedAliasAnalysis.h"
14 #include "llvm/IR/Function.h"
15 #include "llvm/IR/LegacyPassManager.h"
16 #include "llvm/PassInfo.h"
17 #include "llvm/PassRegistry.h"
18 #include "llvm/PassSupport.h"
19 #include "llvm/Support/Debug.h"
20 #include "llvm/Transforms/Scalar.h"
21 #include "llvm/Transforms/Scalar/GVN.h"
22 
23 #define DEBUG_TYPE "polly-cleanup"
24 
25 using namespace llvm;
26 using namespace polly;
27 
28 namespace {
29 
30 class CodegenCleanup : public FunctionPass {
31 private:
32   CodegenCleanup(const CodegenCleanup &) = delete;
33   const CodegenCleanup &operator=(const CodegenCleanup &) = delete;
34 
35   llvm::legacy::FunctionPassManager *FPM;
36 
37 public:
38   static char ID;
39   explicit CodegenCleanup() : FunctionPass(ID), FPM(nullptr) {}
40 
41   /// @name FunctionPass interface
42   //@{
43   virtual void getAnalysisUsage(llvm::AnalysisUsage &AU) const override {}
44 
45   virtual bool doInitialization(Module &M) override {
46     assert(!FPM);
47 
48     FPM = new llvm::legacy::FunctionPassManager(&M);
49 
50     // TODO: How to make parent passes discoverable?
51     // TODO: Should be sensitive to compiler options in PassManagerBuilder, to
52     // which we do not have access here.
53     FPM->add(createScopedNoAliasAAWrapperPass());
54     FPM->add(createTypeBasedAAWrapperPass());
55     FPM->add(createAAResultsWrapperPass());
56 
57     // TODO: These are non-conditional passes that run between
58     // EP_ModuleOptimizerEarly and EP_VectorizerStart just to ensure we do not
59     // miss any optimization that would have run after Polly with
60     // -polly-position=early. This can probably be reduced to a more compact set
61     // of passes.
62     FPM->add(createCFGSimplificationPass());
63     FPM->add(createSROAPass());
64     FPM->add(createEarlyCSEPass());
65 
66     FPM->add(createPromoteMemoryToRegisterPass());
67     FPM->add(createInstructionCombiningPass(true));
68     FPM->add(createCFGSimplificationPass());
69     FPM->add(createSROAPass());
70     FPM->add(createEarlyCSEPass(true));
71     FPM->add(createSpeculativeExecutionIfHasBranchDivergencePass());
72     FPM->add(createJumpThreadingPass());
73     FPM->add(createCorrelatedValuePropagationPass());
74     FPM->add(createCFGSimplificationPass());
75     FPM->add(createInstructionCombiningPass(true));
76     FPM->add(createLibCallsShrinkWrapPass());
77     FPM->add(createTailCallEliminationPass());
78     FPM->add(createCFGSimplificationPass());
79     FPM->add(createReassociatePass());
80     FPM->add(createLoopRotatePass(-1));
81     FPM->add(createGVNPass());
82     FPM->add(createLICMPass());
83     FPM->add(createLoopUnswitchPass());
84     FPM->add(createCFGSimplificationPass());
85     FPM->add(createInstructionCombiningPass(true));
86     FPM->add(createIndVarSimplifyPass());
87     FPM->add(createLoopIdiomPass());
88     FPM->add(createLoopDeletionPass());
89     FPM->add(createCFGSimplificationPass());
90     FPM->add(createSimpleLoopUnrollPass(3));
91     FPM->add(createMergedLoadStoreMotionPass());
92     FPM->add(createGVNPass());
93     FPM->add(createMemCpyOptPass());
94     FPM->add(createSCCPPass());
95     FPM->add(createBitTrackingDCEPass());
96     FPM->add(createInstructionCombiningPass(true));
97     FPM->add(createJumpThreadingPass());
98     FPM->add(createCorrelatedValuePropagationPass());
99     FPM->add(createDeadStoreEliminationPass());
100     FPM->add(createLICMPass());
101     FPM->add(createAggressiveDCEPass());
102     FPM->add(createCFGSimplificationPass());
103     FPM->add(createInstructionCombiningPass(true));
104     FPM->add(createFloat2IntPass());
105 
106     return FPM->doInitialization();
107   }
108 
109   virtual bool doFinalization(Module &M) override {
110     bool Result = FPM->doFinalization();
111 
112     delete FPM;
113     FPM = nullptr;
114 
115     return Result;
116   }
117 
118   virtual bool runOnFunction(llvm::Function &F) override {
119     if (!F.hasFnAttribute("polly-optimized")) {
120       DEBUG(dbgs() << F.getName()
121                    << ": Skipping cleanup because Polly did not optimize it.");
122       return false;
123     }
124 
125     DEBUG(dbgs() << F.getName() << ": Running codegen cleanup...");
126     return FPM->run(F);
127   }
128   //@}
129 };
130 
131 char CodegenCleanup::ID;
132 } // namespace
133 
134 FunctionPass *polly::createCodegenCleanupPass() { return new CodegenCleanup(); }
135 
136 INITIALIZE_PASS_BEGIN(CodegenCleanup, "polly-cleanup",
137                       "Polly - Cleanup after code generation", false, false)
138 INITIALIZE_PASS_END(CodegenCleanup, "polly-cleanup",
139                     "Polly - Cleanup after code generation", false, false)
140