mirror of
https://github.com/c64scene-ar/llvm-6502.git
synced 2025-10-31 08:16:47 +00:00
5a66cb9a44
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@94157 91177308-0d34-0410-b5e6-96231b3b80d8
442 lines
16 KiB
C++
442 lines
16 KiB
C++
//===- CallGraphSCCPass.cpp - Pass that operates BU on call graph ---------===//
|
|
//
|
|
// The LLVM Compiler Infrastructure
|
|
//
|
|
// This file is distributed under the University of Illinois Open Source
|
|
// License. See LICENSE.TXT for details.
|
|
//
|
|
//===----------------------------------------------------------------------===//
|
|
//
|
|
// This file implements the CallGraphSCCPass class, which is used for passes
|
|
// which are implemented as bottom-up traversals on the call graph. Because
|
|
// there may be cycles in the call graph, passes of this type operate on the
|
|
// call-graph in SCC order: that is, they process function bottom-up, except for
|
|
// recursive functions, which they process all at once.
|
|
//
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
#define DEBUG_TYPE "cgscc-passmgr"
|
|
#include "llvm/CallGraphSCCPass.h"
|
|
#include "llvm/Analysis/CallGraph.h"
|
|
#include "llvm/ADT/SCCIterator.h"
|
|
#include "llvm/PassManagers.h"
|
|
#include "llvm/Function.h"
|
|
#include "llvm/Support/Debug.h"
|
|
#include "llvm/IntrinsicInst.h"
|
|
#include "llvm/Support/raw_ostream.h"
|
|
using namespace llvm;
|
|
|
|
//===----------------------------------------------------------------------===//
|
|
// CGPassManager
|
|
//
|
|
/// CGPassManager manages FPPassManagers and CallGraphSCCPasses.
|
|
|
|
namespace {
|
|
|
|
class CGPassManager : public ModulePass, public PMDataManager {
|
|
public:
|
|
static char ID;
|
|
explicit CGPassManager(int Depth)
|
|
: ModulePass(&ID), PMDataManager(Depth) { }
|
|
|
|
/// run - Execute all of the passes scheduled for execution. Keep track of
|
|
/// whether any of the passes modifies the module, and if so, return true.
|
|
bool runOnModule(Module &M);
|
|
|
|
bool doInitialization(CallGraph &CG);
|
|
bool doFinalization(CallGraph &CG);
|
|
|
|
/// Pass Manager itself does not invalidate any analysis info.
|
|
void getAnalysisUsage(AnalysisUsage &Info) const {
|
|
// CGPassManager walks SCC and it needs CallGraph.
|
|
Info.addRequired<CallGraph>();
|
|
Info.setPreservesAll();
|
|
}
|
|
|
|
virtual const char *getPassName() const {
|
|
return "CallGraph Pass Manager";
|
|
}
|
|
|
|
virtual PMDataManager *getAsPMDataManager() { return this; }
|
|
virtual Pass *getAsPass() { return this; }
|
|
|
|
// Print passes managed by this manager
|
|
void dumpPassStructure(unsigned Offset) {
|
|
errs().indent(Offset*2) << "Call Graph SCC Pass Manager\n";
|
|
for (unsigned Index = 0; Index < getNumContainedPasses(); ++Index) {
|
|
Pass *P = getContainedPass(Index);
|
|
P->dumpPassStructure(Offset + 1);
|
|
dumpLastUses(P, Offset+1);
|
|
}
|
|
}
|
|
|
|
Pass *getContainedPass(unsigned N) {
|
|
assert(N < PassVector.size() && "Pass number out of range!");
|
|
return static_cast<Pass *>(PassVector[N]);
|
|
}
|
|
|
|
virtual PassManagerType getPassManagerType() const {
|
|
return PMT_CallGraphPassManager;
|
|
}
|
|
|
|
private:
|
|
bool RunPassOnSCC(Pass *P, std::vector<CallGraphNode*> &CurSCC,
|
|
CallGraph &CG, bool &CallGraphUpToDate);
|
|
void RefreshCallGraph(std::vector<CallGraphNode*> &CurSCC, CallGraph &CG,
|
|
bool IsCheckingMode);
|
|
};
|
|
|
|
} // end anonymous namespace.
|
|
|
|
char CGPassManager::ID = 0;
|
|
|
|
bool CGPassManager::RunPassOnSCC(Pass *P, std::vector<CallGraphNode*> &CurSCC,
|
|
CallGraph &CG, bool &CallGraphUpToDate) {
|
|
bool Changed = false;
|
|
PMDataManager *PM = P->getAsPMDataManager();
|
|
|
|
if (PM == 0) {
|
|
CallGraphSCCPass *CGSP = (CallGraphSCCPass*)P;
|
|
if (!CallGraphUpToDate) {
|
|
RefreshCallGraph(CurSCC, CG, false);
|
|
CallGraphUpToDate = true;
|
|
}
|
|
|
|
Timer *T = StartPassTimer(CGSP);
|
|
Changed = CGSP->runOnSCC(CurSCC);
|
|
StopPassTimer(CGSP, T);
|
|
|
|
// After the CGSCCPass is done, when assertions are enabled, use
|
|
// RefreshCallGraph to verify that the callgraph was correctly updated.
|
|
#ifndef NDEBUG
|
|
if (Changed)
|
|
RefreshCallGraph(CurSCC, CG, true);
|
|
#endif
|
|
|
|
return Changed;
|
|
}
|
|
|
|
|
|
assert(PM->getPassManagerType() == PMT_FunctionPassManager &&
|
|
"Invalid CGPassManager member");
|
|
FPPassManager *FPP = (FPPassManager*)P;
|
|
|
|
// Run pass P on all functions in the current SCC.
|
|
for (unsigned i = 0, e = CurSCC.size(); i != e; ++i) {
|
|
if (Function *F = CurSCC[i]->getFunction()) {
|
|
dumpPassInfo(P, EXECUTION_MSG, ON_FUNCTION_MSG, F->getName());
|
|
Timer *T = StartPassTimer(FPP);
|
|
Changed |= FPP->runOnFunction(*F);
|
|
StopPassTimer(FPP, T);
|
|
}
|
|
}
|
|
|
|
// The function pass(es) modified the IR, they may have clobbered the
|
|
// callgraph.
|
|
if (Changed && CallGraphUpToDate) {
|
|
DEBUG(dbgs() << "CGSCCPASSMGR: Pass Dirtied SCC: "
|
|
<< P->getPassName() << '\n');
|
|
CallGraphUpToDate = false;
|
|
}
|
|
return Changed;
|
|
}
|
|
|
|
|
|
/// RefreshCallGraph - Scan the functions in the specified CFG and resync the
|
|
/// callgraph with the call sites found in it. This is used after
|
|
/// FunctionPasses have potentially munged the callgraph, and can be used after
|
|
/// CallGraphSCC passes to verify that they correctly updated the callgraph.
|
|
///
|
|
void CGPassManager::RefreshCallGraph(std::vector<CallGraphNode*> &CurSCC,
|
|
CallGraph &CG, bool CheckingMode) {
|
|
DenseMap<Value*, CallGraphNode*> CallSites;
|
|
|
|
DEBUG(dbgs() << "CGSCCPASSMGR: Refreshing SCC with " << CurSCC.size()
|
|
<< " nodes:\n";
|
|
for (unsigned i = 0, e = CurSCC.size(); i != e; ++i)
|
|
CurSCC[i]->dump();
|
|
);
|
|
|
|
bool MadeChange = false;
|
|
|
|
// Scan all functions in the SCC.
|
|
for (unsigned sccidx = 0, e = CurSCC.size(); sccidx != e; ++sccidx) {
|
|
CallGraphNode *CGN = CurSCC[sccidx];
|
|
Function *F = CGN->getFunction();
|
|
if (F == 0 || F->isDeclaration()) continue;
|
|
|
|
// Walk the function body looking for call sites. Sync up the call sites in
|
|
// CGN with those actually in the function.
|
|
|
|
// Get the set of call sites currently in the function.
|
|
for (CallGraphNode::iterator I = CGN->begin(), E = CGN->end(); I != E; ) {
|
|
// If this call site is null, then the function pass deleted the call
|
|
// entirely and the WeakVH nulled it out.
|
|
if (I->first == 0 ||
|
|
// If we've already seen this call site, then the FunctionPass RAUW'd
|
|
// one call with another, which resulted in two "uses" in the edge
|
|
// list of the same call.
|
|
CallSites.count(I->first) ||
|
|
|
|
// If the call edge is not from a call or invoke, then the function
|
|
// pass RAUW'd a call with another value. This can happen when
|
|
// constant folding happens of well known functions etc.
|
|
CallSite::get(I->first).getInstruction() == 0) {
|
|
assert(!CheckingMode &&
|
|
"CallGraphSCCPass did not update the CallGraph correctly!");
|
|
|
|
// Just remove the edge from the set of callees, keep track of whether
|
|
// I points to the last element of the vector.
|
|
bool WasLast = I + 1 == E;
|
|
CGN->removeCallEdge(I);
|
|
|
|
// If I pointed to the last element of the vector, we have to bail out:
|
|
// iterator checking rejects comparisons of the resultant pointer with
|
|
// end.
|
|
if (WasLast)
|
|
break;
|
|
E = CGN->end();
|
|
continue;
|
|
}
|
|
|
|
assert(!CallSites.count(I->first) &&
|
|
"Call site occurs in node multiple times");
|
|
CallSites.insert(std::make_pair(I->first, I->second));
|
|
++I;
|
|
}
|
|
|
|
// Loop over all of the instructions in the function, getting the callsites.
|
|
for (Function::iterator BB = F->begin(), E = F->end(); BB != E; ++BB)
|
|
for (BasicBlock::iterator I = BB->begin(), E = BB->end(); I != E; ++I) {
|
|
CallSite CS = CallSite::get(I);
|
|
if (!CS.getInstruction() || isa<DbgInfoIntrinsic>(I)) continue;
|
|
|
|
// If this call site already existed in the callgraph, just verify it
|
|
// matches up to expectations and remove it from CallSites.
|
|
DenseMap<Value*, CallGraphNode*>::iterator ExistingIt =
|
|
CallSites.find(CS.getInstruction());
|
|
if (ExistingIt != CallSites.end()) {
|
|
CallGraphNode *ExistingNode = ExistingIt->second;
|
|
|
|
// Remove from CallSites since we have now seen it.
|
|
CallSites.erase(ExistingIt);
|
|
|
|
// Verify that the callee is right.
|
|
if (ExistingNode->getFunction() == CS.getCalledFunction())
|
|
continue;
|
|
|
|
// If we are in checking mode, we are not allowed to actually mutate
|
|
// the callgraph. If this is a case where we can infer that the
|
|
// callgraph is less precise than it could be (e.g. an indirect call
|
|
// site could be turned direct), don't reject it in checking mode, and
|
|
// don't tweak it to be more precise.
|
|
if (CheckingMode && CS.getCalledFunction() &&
|
|
ExistingNode->getFunction() == 0)
|
|
continue;
|
|
|
|
assert(!CheckingMode &&
|
|
"CallGraphSCCPass did not update the CallGraph correctly!");
|
|
|
|
// If not, we either went from a direct call to indirect, indirect to
|
|
// direct, or direct to different direct.
|
|
CallGraphNode *CalleeNode;
|
|
if (Function *Callee = CS.getCalledFunction())
|
|
CalleeNode = CG.getOrInsertFunction(Callee);
|
|
else
|
|
CalleeNode = CG.getCallsExternalNode();
|
|
|
|
// Update the edge target in CGN.
|
|
for (CallGraphNode::iterator I = CGN->begin(); ; ++I) {
|
|
assert(I != CGN->end() && "Didn't find call entry");
|
|
if (I->first == CS.getInstruction()) {
|
|
I->second = CalleeNode;
|
|
break;
|
|
}
|
|
}
|
|
MadeChange = true;
|
|
continue;
|
|
}
|
|
|
|
assert(!CheckingMode &&
|
|
"CallGraphSCCPass did not update the CallGraph correctly!");
|
|
|
|
// If the call site didn't exist in the CGN yet, add it. We assume that
|
|
// newly introduced call sites won't be indirect. This could be fixed
|
|
// in the future.
|
|
CallGraphNode *CalleeNode;
|
|
if (Function *Callee = CS.getCalledFunction())
|
|
CalleeNode = CG.getOrInsertFunction(Callee);
|
|
else
|
|
CalleeNode = CG.getCallsExternalNode();
|
|
|
|
CGN->addCalledFunction(CS, CalleeNode);
|
|
MadeChange = true;
|
|
}
|
|
|
|
// After scanning this function, if we still have entries in callsites, then
|
|
// they are dangling pointers. WeakVH should save us for this, so abort if
|
|
// this happens.
|
|
assert(CallSites.empty() && "Dangling pointers found in call sites map");
|
|
|
|
// Periodically do an explicit clear to remove tombstones when processing
|
|
// large scc's.
|
|
if ((sccidx & 15) == 0)
|
|
CallSites.clear();
|
|
}
|
|
|
|
DEBUG(if (MadeChange) {
|
|
dbgs() << "CGSCCPASSMGR: Refreshed SCC is now:\n";
|
|
for (unsigned i = 0, e = CurSCC.size(); i != e; ++i)
|
|
CurSCC[i]->dump();
|
|
} else {
|
|
dbgs() << "CGSCCPASSMGR: SCC Refresh didn't change call graph.\n";
|
|
}
|
|
);
|
|
}
|
|
|
|
/// run - Execute all of the passes scheduled for execution. Keep track of
|
|
/// whether any of the passes modifies the module, and if so, return true.
|
|
bool CGPassManager::runOnModule(Module &M) {
|
|
CallGraph &CG = getAnalysis<CallGraph>();
|
|
bool Changed = doInitialization(CG);
|
|
|
|
std::vector<CallGraphNode*> CurSCC;
|
|
|
|
// Walk the callgraph in bottom-up SCC order.
|
|
for (scc_iterator<CallGraph*> CGI = scc_begin(&CG), E = scc_end(&CG);
|
|
CGI != E;) {
|
|
// Copy the current SCC and increment past it so that the pass can hack
|
|
// on the SCC if it wants to without invalidating our iterator.
|
|
CurSCC = *CGI;
|
|
++CGI;
|
|
|
|
|
|
// CallGraphUpToDate - Keep track of whether the callgraph is known to be
|
|
// up-to-date or not. The CGSSC pass manager runs two types of passes:
|
|
// CallGraphSCC Passes and other random function passes. Because other
|
|
// random function passes are not CallGraph aware, they may clobber the
|
|
// call graph by introducing new calls or deleting other ones. This flag
|
|
// is set to false when we run a function pass so that we know to clean up
|
|
// the callgraph when we need to run a CGSCCPass again.
|
|
bool CallGraphUpToDate = true;
|
|
|
|
// Run all passes on current SCC.
|
|
for (unsigned PassNo = 0, e = getNumContainedPasses();
|
|
PassNo != e; ++PassNo) {
|
|
Pass *P = getContainedPass(PassNo);
|
|
|
|
// If we're in -debug-pass=Executions mode, construct the SCC node list,
|
|
// otherwise avoid constructing this string as it is expensive.
|
|
if (isPassDebuggingExecutionsOrMore()) {
|
|
std::string Functions;
|
|
#ifndef NDEBUG
|
|
raw_string_ostream OS(Functions);
|
|
for (unsigned i = 0, e = CurSCC.size(); i != e; ++i) {
|
|
if (i) OS << ", ";
|
|
CurSCC[i]->print(OS);
|
|
}
|
|
OS.flush();
|
|
#endif
|
|
dumpPassInfo(P, EXECUTION_MSG, ON_CG_MSG, Functions);
|
|
}
|
|
dumpRequiredSet(P);
|
|
|
|
initializeAnalysisImpl(P);
|
|
|
|
// Actually run this pass on the current SCC.
|
|
Changed |= RunPassOnSCC(P, CurSCC, CG, CallGraphUpToDate);
|
|
|
|
if (Changed)
|
|
dumpPassInfo(P, MODIFICATION_MSG, ON_CG_MSG, "");
|
|
dumpPreservedSet(P);
|
|
|
|
verifyPreservedAnalysis(P);
|
|
removeNotPreservedAnalysis(P);
|
|
recordAvailableAnalysis(P);
|
|
removeDeadPasses(P, "", ON_CG_MSG);
|
|
}
|
|
|
|
// If the callgraph was left out of date (because the last pass run was a
|
|
// functionpass), refresh it before we move on to the next SCC.
|
|
if (!CallGraphUpToDate)
|
|
RefreshCallGraph(CurSCC, CG, false);
|
|
}
|
|
Changed |= doFinalization(CG);
|
|
return Changed;
|
|
}
|
|
|
|
/// Initialize CG
|
|
bool CGPassManager::doInitialization(CallGraph &CG) {
|
|
bool Changed = false;
|
|
for (unsigned i = 0, e = getNumContainedPasses(); i != e; ++i) {
|
|
if (PMDataManager *PM = getContainedPass(i)->getAsPMDataManager()) {
|
|
assert(PM->getPassManagerType() == PMT_FunctionPassManager &&
|
|
"Invalid CGPassManager member");
|
|
Changed |= ((FPPassManager*)PM)->doInitialization(CG.getModule());
|
|
} else {
|
|
Changed |= ((CallGraphSCCPass*)getContainedPass(i))->doInitialization(CG);
|
|
}
|
|
}
|
|
return Changed;
|
|
}
|
|
|
|
/// Finalize CG
|
|
bool CGPassManager::doFinalization(CallGraph &CG) {
|
|
bool Changed = false;
|
|
for (unsigned i = 0, e = getNumContainedPasses(); i != e; ++i) {
|
|
if (PMDataManager *PM = getContainedPass(i)->getAsPMDataManager()) {
|
|
assert(PM->getPassManagerType() == PMT_FunctionPassManager &&
|
|
"Invalid CGPassManager member");
|
|
Changed |= ((FPPassManager*)PM)->doFinalization(CG.getModule());
|
|
} else {
|
|
Changed |= ((CallGraphSCCPass*)getContainedPass(i))->doFinalization(CG);
|
|
}
|
|
}
|
|
return Changed;
|
|
}
|
|
|
|
/// Assign pass manager to manage this pass.
|
|
void CallGraphSCCPass::assignPassManager(PMStack &PMS,
|
|
PassManagerType PreferredType) {
|
|
// Find CGPassManager
|
|
while (!PMS.empty() &&
|
|
PMS.top()->getPassManagerType() > PMT_CallGraphPassManager)
|
|
PMS.pop();
|
|
|
|
assert(!PMS.empty() && "Unable to handle Call Graph Pass");
|
|
CGPassManager *CGP;
|
|
|
|
if (PMS.top()->getPassManagerType() == PMT_CallGraphPassManager)
|
|
CGP = (CGPassManager*)PMS.top();
|
|
else {
|
|
// Create new Call Graph SCC Pass Manager if it does not exist.
|
|
assert(!PMS.empty() && "Unable to create Call Graph Pass Manager");
|
|
PMDataManager *PMD = PMS.top();
|
|
|
|
// [1] Create new Call Graph Pass Manager
|
|
CGP = new CGPassManager(PMD->getDepth() + 1);
|
|
|
|
// [2] Set up new manager's top level manager
|
|
PMTopLevelManager *TPM = PMD->getTopLevelManager();
|
|
TPM->addIndirectPassManager(CGP);
|
|
|
|
// [3] Assign manager to manage this new manager. This may create
|
|
// and push new managers into PMS
|
|
Pass *P = CGP;
|
|
TPM->schedulePass(P);
|
|
|
|
// [4] Push new manager into PMS
|
|
PMS.push(CGP);
|
|
}
|
|
|
|
CGP->add(this);
|
|
}
|
|
|
|
/// getAnalysisUsage - For this class, we declare that we require and preserve
|
|
/// the call graph. If the derived class implements this method, it should
|
|
/// always explicitly call the implementation here.
|
|
void CallGraphSCCPass::getAnalysisUsage(AnalysisUsage &AU) const {
|
|
AU.addRequired<CallGraph>();
|
|
AU.addPreserved<CallGraph>();
|
|
}
|