1 //===- llvm/IR/OptBisect/Bisect.cpp - LLVM Bisect support -----------------===//
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 //===----------------------------------------------------------------------===//
11 /// This file implements support for a bisecting optimizations based on a
12 /// command line option.
14 //===----------------------------------------------------------------------===//
16 #include "llvm/IR/OptBisect.h"
17 #include "llvm/ADT/StringRef.h"
18 #include "llvm/Analysis/CallGraph.h"
19 #include "llvm/Analysis/CallGraphSCCPass.h"
20 #include "llvm/Analysis/LoopInfo.h"
21 #include "llvm/Analysis/RegionInfo.h"
22 #include "llvm/IR/BasicBlock.h"
23 #include "llvm/IR/Function.h"
24 #include "llvm/IR/Module.h"
25 #include "llvm/Pass.h"
26 #include "llvm/Support/CommandLine.h"
27 #include "llvm/Support/raw_ostream.h"
34 static cl::opt<int> OptBisectLimit("opt-bisect-limit", cl::Hidden,
35 cl::init(std::numeric_limits<int>::max()),
37 cl::desc("Maximum optimization to perform"));
39 OptBisect::OptBisect() : OptPassGate() {
40 BisectEnabled = OptBisectLimit != std::numeric_limits<int>::max();
43 static void printPassMessage(const StringRef &Name, int PassNum,
44 StringRef TargetDesc, bool Running) {
45 StringRef Status = Running ? "" : "NOT ";
46 errs() << "BISECT: " << Status << "running pass "
47 << "(" << PassNum << ") " << Name << " on " << TargetDesc << "\n";
50 static std::string getDescription(const Module &M) {
51 return "module (" + M.getName().str() + ")";
54 static std::string getDescription(const Function &F) {
55 return "function (" + F.getName().str() + ")";
58 static std::string getDescription(const BasicBlock &BB) {
59 return "basic block (" + BB.getName().str() + ") in function (" +
60 BB.getParent()->getName().str() + ")";
63 static std::string getDescription(const Loop &L) {
64 // FIXME: Move into LoopInfo so we can get a better description
65 // (and avoid a circular dependency between IR and Analysis).
69 static std::string getDescription(const Region &R) {
70 // FIXME: Move into RegionInfo so we can get a better description
71 // (and avoid a circular dependency between IR and Analysis).
75 static std::string getDescription(const CallGraphSCC &SCC) {
76 // FIXME: Move into CallGraphSCCPass to avoid circular dependency between
78 std::string Desc = "SCC (";
80 for (CallGraphNode *CGN : SCC) {
85 Function *F = CGN->getFunction();
89 Desc += "<<null function>>";
95 bool OptBisect::shouldRunPass(const Pass *P, const Module &U) {
96 return !BisectEnabled || checkPass(P->getPassName(), getDescription(U));
99 bool OptBisect::shouldRunPass(const Pass *P, const Function &U) {
100 return !BisectEnabled || checkPass(P->getPassName(), getDescription(U));
103 bool OptBisect::shouldRunPass(const Pass *P, const BasicBlock &U) {
104 return !BisectEnabled || checkPass(P->getPassName(), getDescription(U));
107 bool OptBisect::shouldRunPass(const Pass *P, const Region &U) {
108 return !BisectEnabled || checkPass(P->getPassName(), getDescription(U));
111 bool OptBisect::shouldRunPass(const Pass *P, const Loop &U) {
112 return !BisectEnabled || checkPass(P->getPassName(), getDescription(U));
115 bool OptBisect::shouldRunPass(const Pass *P, const CallGraphSCC &U) {
116 return !BisectEnabled || checkPass(P->getPassName(), getDescription(U));
119 bool OptBisect::checkPass(const StringRef PassName,
120 const StringRef TargetDesc) {
121 assert(BisectEnabled);
123 int CurBisectNum = ++LastBisectNum;
124 bool ShouldRun = (OptBisectLimit == -1 || CurBisectNum <= OptBisectLimit);
125 printPassMessage(PassName, CurBisectNum, TargetDesc, ShouldRun);