• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
1 //===- AnalysisWrappers.cpp - Wrappers around non-pass analyses -----------===//
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 // This file defines pass wrappers around LLVM analyses that don't make sense to
11 // be passes.  It provides a nice standard pass interface to these classes so
12 // that they can be printed out by analyze.
13 //
14 // These classes are separated out of analyze.cpp so that it is more clear which
15 // code is the integral part of the analyze tool, and which part of the code is
16 // just making it so more passes are available.
17 //
18 //===----------------------------------------------------------------------===//
19 
20 #include "llvm/Module.h"
21 #include "llvm/Pass.h"
22 #include "llvm/Support/CallSite.h"
23 #include "llvm/Analysis/CallGraph.h"
24 #include "llvm/Support/raw_ostream.h"
25 using namespace llvm;
26 
27 namespace {
28   /// ExternalFunctionsPassedConstants - This pass prints out call sites to
29   /// external functions that are called with constant arguments.  This can be
30   /// useful when looking for standard library functions we should constant fold
31   /// or handle in alias analyses.
32   struct ExternalFunctionsPassedConstants : public ModulePass {
33     static char ID; // Pass ID, replacement for typeid
ExternalFunctionsPassedConstants__anon1e898d3b0111::ExternalFunctionsPassedConstants34     ExternalFunctionsPassedConstants() : ModulePass(ID) {}
runOnModule__anon1e898d3b0111::ExternalFunctionsPassedConstants35     virtual bool runOnModule(Module &M) {
36       for (Module::iterator I = M.begin(), E = M.end(); I != E; ++I) {
37         if (!I->isDeclaration()) continue;
38 
39         bool PrintedFn = false;
40         for (Value::use_iterator UI = I->use_begin(), E = I->use_end();
41              UI != E; ++UI) {
42           Instruction *User = dyn_cast<Instruction>(*UI);
43           if (!User) continue;
44 
45           CallSite CS(cast<Value>(User));
46           if (!CS) continue;
47 
48           for (CallSite::arg_iterator AI = CS.arg_begin(),
49                E = CS.arg_end(); AI != E; ++AI) {
50             if (!isa<Constant>(*AI)) continue;
51 
52             if (!PrintedFn) {
53               errs() << "Function '" << I->getName() << "':\n";
54               PrintedFn = true;
55             }
56             errs() << *User;
57             break;
58           }
59         }
60       }
61 
62       return false;
63     }
64 
getAnalysisUsage__anon1e898d3b0111::ExternalFunctionsPassedConstants65     virtual void getAnalysisUsage(AnalysisUsage &AU) const {
66       AU.setPreservesAll();
67     }
68   };
69 }
70 
71 char ExternalFunctionsPassedConstants::ID = 0;
72 static RegisterPass<ExternalFunctionsPassedConstants>
73   P1("print-externalfnconstants",
74      "Print external fn callsites passed constants");
75 
76 namespace {
77   struct CallGraphPrinter : public ModulePass {
78     static char ID; // Pass ID, replacement for typeid
CallGraphPrinter__anon1e898d3b0211::CallGraphPrinter79     CallGraphPrinter() : ModulePass(ID) {}
80 
getAnalysisUsage__anon1e898d3b0211::CallGraphPrinter81     virtual void getAnalysisUsage(AnalysisUsage &AU) const {
82       AU.setPreservesAll();
83       AU.addRequiredTransitive<CallGraph>();
84     }
runOnModule__anon1e898d3b0211::CallGraphPrinter85     virtual bool runOnModule(Module &M) {
86       getAnalysis<CallGraph>().print(errs(), &M);
87       return false;
88     }
89   };
90 }
91 
92 char CallGraphPrinter::ID = 0;
93 static RegisterPass<CallGraphPrinter>
94   P2("print-callgraph", "Print a call graph");
95