llvm-6502/lib/VMCore/Pass.cpp
Chris Lattner 27ad137d5e Make functions that preserve the CFG not invalidate analyses that only depend
on the CFG of a function


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@2506 91177308-0d34-0410-b5e6-96231b3b80d8
2002-05-06 19:31:52 +00:00

284 lines
9.7 KiB
C++

//===- Pass.cpp - LLVM Pass Infrastructure Impementation ------------------===//
//
// This file implements the LLVM Pass infrastructure. It is primarily
// responsible with ensuring that passes are executed and batched together
// optimally.
//
//===----------------------------------------------------------------------===//
#include "llvm/PassManager.h"
#include "PassManagerT.h" // PassManagerT implementation
#include "llvm/Module.h"
#include "llvm/Function.h"
#include "llvm/BasicBlock.h"
#include "Support/STLExtras.h"
#include "Support/CommandLine.h"
#include <typeinfo>
#include <iostream>
#include <sys/time.h>
#include <stdio.h>
//===----------------------------------------------------------------------===//
// AnalysisID Class Implementation
//
static std::vector<AnalysisID> CFGOnlyAnalyses;
// Source of unique analysis ID #'s.
unsigned AnalysisID::NextID = 0;
AnalysisID::AnalysisID(const AnalysisID &AID, bool DependsOnlyOnCFG) {
ID = AID.ID; // Implement the copy ctor part...
Constructor = AID.Constructor;
// If this analysis only depends on the CFG of the function, add it to the CFG
// only list...
if (DependsOnlyOnCFG)
CFGOnlyAnalyses.push_back(AID);
}
//===----------------------------------------------------------------------===//
// AnalysisResolver Class Implementation
//
void AnalysisResolver::setAnalysisResolver(Pass *P, AnalysisResolver *AR) {
assert(P->Resolver == 0 && "Pass already in a PassManager!");
P->Resolver = AR;
}
//===----------------------------------------------------------------------===//
// AnalysisUsage Class Implementation
//
// preservesCFG - This function should be called to by the pass, iff they do
// not:
//
// 1. Add or remove basic blocks from the function
// 2. Modify terminator instructions in any way.
//
// This function annotates the AnalysisUsage info object to say that analyses
// that only depend on the CFG are preserved by this pass.
//
void AnalysisUsage::preservesCFG() {
// Since this transformation doesn't modify the CFG, it preserves all analyses
// that only depend on the CFG (like dominators, loop info, etc...)
//
Preserved.insert(Preserved.end(),
CFGOnlyAnalyses.begin(), CFGOnlyAnalyses.end());
}
//===----------------------------------------------------------------------===//
// PassManager implementation - The PassManager class is a simple Pimpl class
// that wraps the PassManagerT template.
//
PassManager::PassManager() : PM(new PassManagerT<Module>()) {}
PassManager::~PassManager() { delete PM; }
void PassManager::add(Pass *P) { PM->add(P); }
bool PassManager::run(Module *M) { return PM->run(M); }
//===----------------------------------------------------------------------===//
// TimingInfo Class - This class is used to calculate information about the
// amount of time each pass takes to execute. This only happens with
// -time-passes is enabled on the command line.
//
static cl::Flag EnableTiming("time-passes", "Time each pass, printing elapsed"
" time for each on exit");
static double getTime() {
struct timeval T;
gettimeofday(&T, 0);
return T.tv_sec + T.tv_usec/1000000.0;
}
// Create method. If Timing is enabled, this creates and returns a new timing
// object, otherwise it returns null.
//
TimingInfo *TimingInfo::create() {
return EnableTiming ? new TimingInfo() : 0;
}
void TimingInfo::passStarted(Pass *P) { TimingData[P] -= getTime(); }
void TimingInfo::passEnded(Pass *P) { TimingData[P] += getTime(); }
// TimingDtor - Print out information about timing information
TimingInfo::~TimingInfo() {
// Iterate over all of the data, converting it into the dual of the data map,
// so that the data is sorted by amount of time taken, instead of pointer.
//
std::vector<pair<double, Pass*> > Data;
double TotalTime = 0;
for (std::map<Pass*, double>::iterator I = TimingData.begin(),
E = TimingData.end(); I != E; ++I)
// Throw out results for "grouping" pass managers...
if (!dynamic_cast<AnalysisResolver*>(I->first)) {
Data.push_back(std::make_pair(I->second, I->first));
TotalTime += I->second;
}
// Sort the data by time as the primary key, in reverse order...
std::sort(Data.begin(), Data.end(), greater<pair<double, Pass*> >());
// Print out timing header...
cerr << std::string(79, '=') << "\n"
<< " ... Pass execution timing report ...\n"
<< std::string(79, '=') << "\n Total Execution Time: " << TotalTime
<< " seconds\n\n % Time: Seconds:\tPass Name:\n";
// Loop through all of the timing data, printing it out...
for (unsigned i = 0, e = Data.size(); i != e; ++i) {
fprintf(stderr, " %6.2f%% %fs\t%s\n", Data[i].first*100 / TotalTime,
Data[i].first, Data[i].second->getPassName());
}
cerr << " 100.00% " << TotalTime << "s\tTOTAL\n"
<< std::string(79, '=') << "\n";
}
//===----------------------------------------------------------------------===//
// Pass debugging information. Often it is useful to find out what pass is
// running when a crash occurs in a utility. When this library is compiled with
// debugging on, a command line option (--debug-pass) is enabled that causes the
// pass name to be printed before it executes.
//
// Different debug levels that can be enabled...
enum PassDebugLevel {
None, PassStructure, PassExecutions, PassDetails
};
static cl::Enum<enum PassDebugLevel> PassDebugging("debug-pass", cl::Hidden,
"Print PassManager debugging information",
clEnumVal(None , "disable debug output"),
clEnumVal(PassStructure , "print pass structure before run()"),
clEnumVal(PassExecutions, "print pass name before it is executed"),
clEnumVal(PassDetails , "print pass details when it is executed"), 0);
void PMDebug::PrintPassStructure(Pass *P) {
if (PassDebugging >= PassStructure)
P->dumpPassStructure();
}
void PMDebug::PrintPassInformation(unsigned Depth, const char *Action,
Pass *P, Annotable *V) {
if (PassDebugging >= PassExecutions) {
std::cerr << (void*)P << std::string(Depth*2+1, ' ') << Action << " '"
<< P->getPassName();
if (V) {
std::cerr << "' on ";
if (dynamic_cast<Module*>(V)) {
std::cerr << "Module\n"; return;
} else if (Function *F = dynamic_cast<Function*>(V))
std::cerr << "Function '" << F->getName();
else if (BasicBlock *BB = dynamic_cast<BasicBlock*>(V))
std::cerr << "BasicBlock '" << BB->getName();
else if (Value *Val = dynamic_cast<Value*>(V))
std::cerr << typeid(*Val).name() << " '" << Val->getName();
}
std::cerr << "'...\n";
}
}
void PMDebug::PrintAnalysisSetInfo(unsigned Depth, const char *Msg,
Pass *P, const std::vector<AnalysisID> &Set){
if (PassDebugging >= PassDetails && !Set.empty()) {
std::cerr << (void*)P << std::string(Depth*2+3, ' ') << Msg << " Analyses:";
for (unsigned i = 0; i != Set.size(); ++i) {
Pass *P = Set[i].createPass(); // Good thing this is just debug code...
std::cerr << " " << P->getPassName();
delete P;
}
std::cerr << "\n";
}
}
// dumpPassStructure - Implement the -debug-passes=PassStructure option
void Pass::dumpPassStructure(unsigned Offset = 0) {
std::cerr << std::string(Offset*2, ' ') << getPassName() << "\n";
}
//===----------------------------------------------------------------------===//
// Pass Implementation
//
void Pass::addToPassManager(PassManagerT<Module> *PM, AnalysisUsage &AU) {
PM->addPass(this, AU);
}
// getPassName - Use C++ RTTI to get a SOMEWHAT intelligable name for the pass.
//
const char *Pass::getPassName() const { return typeid(*this).name(); }
//===----------------------------------------------------------------------===//
// FunctionPass Implementation
//
// run - On a module, we run this pass by initializing, runOnFunction'ing once
// for every function in the module, then by finalizing.
//
bool FunctionPass::run(Module *M) {
bool Changed = doInitialization(M);
for (Module::iterator I = M->begin(), E = M->end(); I != E; ++I)
if (!(*I)->isExternal()) // Passes are not run on external functions!
Changed |= runOnFunction(*I);
return Changed | doFinalization(M);
}
// run - On a function, we simply initialize, run the function, then finalize.
//
bool FunctionPass::run(Function *F) {
if (F->isExternal()) return false;// Passes are not run on external functions!
return doInitialization(F->getParent()) | runOnFunction(F)
| doFinalization(F->getParent());
}
void FunctionPass::addToPassManager(PassManagerT<Module> *PM,
AnalysisUsage &AU) {
PM->addPass(this, AU);
}
void FunctionPass::addToPassManager(PassManagerT<Function> *PM,
AnalysisUsage &AU) {
PM->addPass(this, AU);
}
//===----------------------------------------------------------------------===//
// BasicBlockPass Implementation
//
// To run this pass on a function, we simply call runOnBasicBlock once for each
// function.
//
bool BasicBlockPass::runOnFunction(Function *F) {
bool Changed = false;
for (Function::iterator I = F->begin(), E = F->end(); I != E; ++I)
Changed |= runOnBasicBlock(*I);
return Changed;
}
// To run directly on the basic block, we initialize, runOnBasicBlock, then
// finalize.
//
bool BasicBlockPass::run(BasicBlock *BB) {
Module *M = BB->getParent()->getParent();
return doInitialization(M) | runOnBasicBlock(BB) | doFinalization(M);
}
void BasicBlockPass::addToPassManager(PassManagerT<Function> *PM,
AnalysisUsage &AU) {
PM->addPass(this, AU);
}
void BasicBlockPass::addToPassManager(PassManagerT<BasicBlock> *PM,
AnalysisUsage &AU) {
PM->addPass(this, AU);
}