1 //===- Optimize.cpp - Optimize a complete program -------------------------===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file implements all optimization of the linked module for llvm-ld.
12 //===----------------------------------------------------------------------===//
14 #include "llvm/Module.h"
15 #include "llvm/PassManager.h"
16 #include "llvm/Analysis/Passes.h"
17 #include "llvm/Analysis/LoopPass.h"
18 #include "llvm/Analysis/Verifier.h"
19 #include "llvm/Support/CommandLine.h"
20 #include "llvm/Support/StandardPasses.h"
21 #include "llvm/Support/raw_ostream.h"
22 #include "llvm/System/DynamicLibrary.h"
23 #include "llvm/Target/TargetData.h"
24 #include "llvm/Target/TargetMachine.h"
25 #include "llvm/Transforms/IPO.h"
26 #include "llvm/Transforms/Scalar.h"
27 #include "llvm/Support/PassNameParser.h"
28 #include "llvm/Support/PluginLoader.h"
32 // Pass Name Options as generated by the PassNameParser
33 static cl::list<const PassInfo*, bool, PassNameParser>
34 OptimizationList(cl::desc("Optimizations available:"));
36 //Don't verify at the end
37 static cl::opt<bool> DontVerify("disable-verify", cl::ReallyHidden);
39 static cl::opt<bool> DisableInline("disable-inlining",
40 cl::desc("Do not run the inliner pass"));
43 DisableOptimizations("disable-opt",
44 cl::desc("Do not run any optimization passes"));
46 static cl::opt<bool> DisableInternalize("disable-internalize",
47 cl::desc("Do not mark all symbols as internal"));
49 static cl::opt<bool> VerifyEach("verify-each",
50 cl::desc("Verify intermediate results of all passes"));
52 static cl::alias ExportDynamic("export-dynamic",
53 cl::aliasopt(DisableInternalize),
54 cl::desc("Alias for -disable-internalize"));
56 static cl::opt<bool> Strip("strip-all",
57 cl::desc("Strip all symbol info from executable"));
59 static cl::alias A0("s", cl::desc("Alias for --strip-all"),
62 static cl::opt<bool> StripDebug("strip-debug",
63 cl::desc("Strip debugger symbol info from executable"));
65 static cl::alias A1("S", cl::desc("Alias for --strip-debug"),
66 cl::aliasopt(StripDebug));
68 // A utility function that adds a pass to the pass manager but will also add
69 // a verifier pass after if we're supposed to verify.
70 static inline void addPass(PassManager &PM, Pass *P) {
71 // Add the pass to the pass manager...
74 // If we are verifying all of the intermediate steps, add the verifier...
76 PM.add(createVerifierPass());
81 /// Optimize - Perform link time optimizations. This will run the scalar
82 /// optimizations, any loaded plugin-optimization modules, and then the
83 /// inter-procedural optimizations if applicable.
84 void Optimize(Module* M) {
86 // Instantiate the pass manager to organize the passes.
89 // If we're verifying, start off with a verification pass.
91 Passes.add(createVerifierPass());
93 // Add an appropriate TargetData instance for this module...
94 addPass(Passes, new TargetData(M));
96 if (!DisableOptimizations)
97 createStandardLTOPasses(&Passes, !DisableInternalize, !DisableInline,
100 // If the -s or -S command line options were specified, strip the symbols out
101 // of the resulting program to make it smaller. -s and -S are GNU ld options
102 // that we are supporting; they alias -strip-all and -strip-debug.
103 if (Strip || StripDebug)
104 addPass(Passes, createStripSymbolsPass(StripDebug && !Strip));
106 // Create a new optimization pass for each one specified on the command line
107 std::auto_ptr<TargetMachine> target;
108 for (unsigned i = 0; i < OptimizationList.size(); ++i) {
109 const PassInfo *Opt = OptimizationList[i];
110 if (Opt->getNormalCtor())
111 addPass(Passes, Opt->getNormalCtor()());
113 errs() << "llvm-ld: cannot create pass: " << Opt->getPassName()
117 // The user's passes may leave cruft around. Clean up after them them but
118 // only if we haven't got DisableOptimizations set
119 if (!DisableOptimizations) {
120 addPass(Passes, createInstructionCombiningPass());
121 addPass(Passes, createCFGSimplificationPass());
122 addPass(Passes, createAggressiveDCEPass());
123 addPass(Passes, createGlobalDCEPass());
126 // Make sure everything is still good.
128 Passes.add(createVerifierPass());
130 // Run our queue of passes all at once now, efficiently.