llvm-project/llvm/tools/opt/AnalysisWrappers.cpp

93 lines
3.1 KiB
C++

//===- AnalysisWrappers.cpp - Wrappers around non-pass analyses -----------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file defines pass wrappers around LLVM analyses that don't make sense to
// be passes. It provides a nice standard pass interface to these classes so
// that they can be printed out by analyze.
//
// These classes are separated out of analyze.cpp so that it is more clear which
// code is the integral part of the analyze tool, and which part of the code is
// just making it so more passes are available.
//
//===----------------------------------------------------------------------===//
#include "llvm/Module.h"
#include "llvm/Pass.h"
#include "llvm/Support/CallSite.h"
#include "llvm/Analysis/CallGraph.h"
#include "llvm/Support/raw_ostream.h"
using namespace llvm;
namespace {
/// ExternalFunctionsPassedConstants - This pass prints out call sites to
/// external functions that are called with constant arguments. This can be
/// useful when looking for standard library functions we should constant fold
/// or handle in alias analyses.
struct ExternalFunctionsPassedConstants : public ModulePass {
static char ID; // Pass ID, replacement for typeid
ExternalFunctionsPassedConstants() : ModulePass(&ID) {}
virtual bool runOnModule(Module &M) {
for (Module::iterator I = M.begin(), E = M.end(); I != E; ++I) {
if (!I->isDeclaration()) continue;
bool PrintedFn = false;
for (Value::use_iterator UI = I->use_begin(), E = I->use_end();
UI != E; ++UI) {
Instruction *User = dyn_cast<Instruction>(*UI);
if (!User) continue;
CallSite CS(cast<Value>(User));
if (!CS) continue;
for (CallSite::arg_iterator AI = CS.arg_begin(),
E = CS.arg_end(); AI != E; ++AI) {
if (!isa<Constant>(*AI)) continue;
if (!PrintedFn) {
errs() << "Function '" << I->getName() << "':\n";
PrintedFn = true;
}
errs() << *User;
break;
}
}
}
return false;
}
virtual void getAnalysisUsage(AnalysisUsage &AU) const {
AU.setPreservesAll();
}
};
char ExternalFunctionsPassedConstants::ID = 0;
RegisterPass<ExternalFunctionsPassedConstants>
P1("print-externalfnconstants",
"Print external fn callsites passed constants");
struct CallGraphPrinter : public ModulePass {
static char ID; // Pass ID, replacement for typeid
CallGraphPrinter() : ModulePass(&ID) {}
virtual void getAnalysisUsage(AnalysisUsage &AU) const {
AU.setPreservesAll();
AU.addRequiredTransitive<CallGraph>();
}
virtual bool runOnModule(Module &M) {
getAnalysis<CallGraph>().print(errs(), &M);
return false;
}
};
char CallGraphPrinter::ID = 0;
RegisterPass<CallGraphPrinter>
P2("print-callgraph", "Print a call graph");
}