llvm-6502/lib/Analysis/DataStructure/BottomUpClosure.cpp
Andrew Lenharth 5e091f3e32 friendlier error message
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@27829 91177308-0d34-0410-b5e6-96231b3b80d8
2006-04-19 15:33:35 +00:00

681 lines
24 KiB
C++

//===- BottomUpClosure.cpp - Compute bottom-up interprocedural closure ----===//
//
// The LLVM Compiler Infrastructure
//
// This file was developed by the LLVM research group and is distributed under
// the University of Illinois Open Source License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements the BUDataStructures class, which represents the
// Bottom-Up Interprocedural closure of the data structure graph over the
// program. This is useful for applications like pool allocation, but **not**
// applications like alias analysis.
//
//===----------------------------------------------------------------------===//
#include "llvm/Analysis/DataStructure/DataStructure.h"
#include "llvm/Analysis/DataStructure/DSGraph.h"
#include "llvm/Module.h"
#include "llvm/ADT/Statistic.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/Timer.h"
#include <iostream>
using namespace llvm;
namespace {
Statistic<> MaxSCC("budatastructure", "Maximum SCC Size in Call Graph");
Statistic<> NumBUInlines("budatastructures", "Number of graphs inlined");
Statistic<> NumCallEdges("budatastructures", "Number of 'actual' call edges");
RegisterAnalysis<BUDataStructures>
X("budatastructure", "Bottom-up Data Structure Analysis");
}
/// BuildGlobalECs - Look at all of the nodes in the globals graph. If any node
/// contains multiple globals, DSA will never, ever, be able to tell the globals
/// apart. Instead of maintaining this information in all of the graphs
/// throughout the entire program, store only a single global (the "leader") in
/// the graphs, and build equivalence classes for the rest of the globals.
static void BuildGlobalECs(DSGraph &GG, std::set<GlobalValue*> &ECGlobals) {
DSScalarMap &SM = GG.getScalarMap();
EquivalenceClasses<GlobalValue*> &GlobalECs = SM.getGlobalECs();
for (DSGraph::node_iterator I = GG.node_begin(), E = GG.node_end();
I != E; ++I) {
if (I->getGlobalsList().size() <= 1) continue;
// First, build up the equivalence set for this block of globals.
const std::vector<GlobalValue*> &GVs = I->getGlobalsList();
GlobalValue *First = GVs[0];
for (unsigned i = 1, e = GVs.size(); i != e; ++i)
GlobalECs.unionSets(First, GVs[i]);
// Next, get the leader element.
assert(First == GlobalECs.getLeaderValue(First) &&
"First did not end up being the leader?");
// Next, remove all globals from the scalar map that are not the leader.
assert(GVs[0] == First && "First had to be at the front!");
for (unsigned i = 1, e = GVs.size(); i != e; ++i) {
ECGlobals.insert(GVs[i]);
SM.erase(SM.find(GVs[i]));
}
// Finally, change the global node to only contain the leader.
I->clearGlobals();
I->addGlobal(First);
}
DEBUG(GG.AssertGraphOK());
}
/// EliminateUsesOfECGlobals - Once we have determined that some globals are in
/// really just equivalent to some other globals, remove the globals from the
/// specified DSGraph (if present), and merge any nodes with their leader nodes.
static void EliminateUsesOfECGlobals(DSGraph &G,
const std::set<GlobalValue*> &ECGlobals) {
DSScalarMap &SM = G.getScalarMap();
EquivalenceClasses<GlobalValue*> &GlobalECs = SM.getGlobalECs();
bool MadeChange = false;
for (DSScalarMap::global_iterator GI = SM.global_begin(), E = SM.global_end();
GI != E; ) {
GlobalValue *GV = *GI++;
if (!ECGlobals.count(GV)) continue;
const DSNodeHandle &GVNH = SM[GV];
assert(!GVNH.isNull() && "Global has null NH!?");
// Okay, this global is in some equivalence class. Start by finding the
// leader of the class.
GlobalValue *Leader = GlobalECs.getLeaderValue(GV);
// If the leader isn't already in the graph, insert it into the node
// corresponding to GV.
if (!SM.global_count(Leader)) {
GVNH.getNode()->addGlobal(Leader);
SM[Leader] = GVNH;
} else {
// Otherwise, the leader is in the graph, make sure the nodes are the
// merged in the specified graph.
const DSNodeHandle &LNH = SM[Leader];
if (LNH.getNode() != GVNH.getNode())
LNH.mergeWith(GVNH);
}
// Next step, remove the global from the DSNode.
GVNH.getNode()->removeGlobal(GV);
// Finally, remove the global from the ScalarMap.
SM.erase(GV);
MadeChange = true;
}
DEBUG(if(MadeChange) G.AssertGraphOK());
}
// run - Calculate the bottom up data structure graphs for each function in the
// program.
//
bool BUDataStructures::runOnModule(Module &M) {
LocalDataStructures &LocalDSA = getAnalysis<LocalDataStructures>();
GlobalECs = LocalDSA.getGlobalECs();
GlobalsGraph = new DSGraph(LocalDSA.getGlobalsGraph(), GlobalECs);
GlobalsGraph->setPrintAuxCalls();
IndCallGraphMap = new std::map<std::vector<Function*>,
std::pair<DSGraph*, std::vector<DSNodeHandle> > >();
std::vector<Function*> Stack;
hash_map<Function*, unsigned> ValMap;
unsigned NextID = 1;
Function *MainFunc = M.getMainFunction();
if (MainFunc)
calculateGraphs(MainFunc, Stack, NextID, ValMap);
// Calculate the graphs for any functions that are unreachable from main...
for (Module::iterator I = M.begin(), E = M.end(); I != E; ++I)
if (!I->isExternal() && !DSInfo.count(I)) {
#ifndef NDEBUG
if (MainFunc)
std::cerr << "*** BU: Function unreachable from main: "
<< I->getName() << "\n";
#endif
calculateGraphs(I, Stack, NextID, ValMap); // Calculate all graphs.
}
NumCallEdges += ActualCallees.size();
// If we computed any temporary indcallgraphs, free them now.
for (std::map<std::vector<Function*>,
std::pair<DSGraph*, std::vector<DSNodeHandle> > >::iterator I =
IndCallGraphMap->begin(), E = IndCallGraphMap->end(); I != E; ++I) {
I->second.second.clear(); // Drop arg refs into the graph.
delete I->second.first;
}
delete IndCallGraphMap;
// At the end of the bottom-up pass, the globals graph becomes complete.
// FIXME: This is not the right way to do this, but it is sorta better than
// nothing! In particular, externally visible globals and unresolvable call
// nodes at the end of the BU phase should make things that they point to
// incomplete in the globals graph.
//
GlobalsGraph->removeTriviallyDeadNodes();
GlobalsGraph->maskIncompleteMarkers();
// Mark external globals incomplete.
GlobalsGraph->markIncompleteNodes(DSGraph::IgnoreGlobals);
// Grow the equivalence classes for the globals to include anything that we
// now know to be aliased.
std::set<GlobalValue*> ECGlobals;
BuildGlobalECs(*GlobalsGraph, ECGlobals);
if (!ECGlobals.empty()) {
NamedRegionTimer X("Bottom-UP EC Cleanup");
std::cerr << "Eliminating " << ECGlobals.size() << " EC Globals!\n";
for (hash_map<Function*, DSGraph*>::iterator I = DSInfo.begin(),
E = DSInfo.end(); I != E; ++I)
EliminateUsesOfECGlobals(*I->second, ECGlobals);
}
// Merge the globals variables (not the calls) from the globals graph back
// into the main function's graph so that the main function contains all of
// the information about global pools and GV usage in the program.
if (MainFunc && !MainFunc->isExternal()) {
DSGraph &MainGraph = getOrCreateGraph(MainFunc);
const DSGraph &GG = *MainGraph.getGlobalsGraph();
ReachabilityCloner RC(MainGraph, GG,
DSGraph::DontCloneCallNodes |
DSGraph::DontCloneAuxCallNodes);
// Clone the global nodes into this graph.
for (DSScalarMap::global_iterator I = GG.getScalarMap().global_begin(),
E = GG.getScalarMap().global_end(); I != E; ++I)
if (isa<GlobalVariable>(*I))
RC.getClonedNH(GG.getNodeForValue(*I));
MainGraph.maskIncompleteMarkers();
MainGraph.markIncompleteNodes(DSGraph::MarkFormalArgs |
DSGraph::IgnoreGlobals);
}
return false;
}
DSGraph &BUDataStructures::getOrCreateGraph(Function *F) {
// Has the graph already been created?
DSGraph *&Graph = DSInfo[F];
if (Graph) return *Graph;
DSGraph &LocGraph = getAnalysis<LocalDataStructures>().getDSGraph(*F);
// Steal the local graph.
Graph = new DSGraph(GlobalECs, LocGraph.getTargetData());
Graph->spliceFrom(LocGraph);
Graph->setGlobalsGraph(GlobalsGraph);
Graph->setPrintAuxCalls();
// Start with a copy of the original call sites...
Graph->getAuxFunctionCalls() = Graph->getFunctionCalls();
return *Graph;
}
static bool isVAHackFn(const Function *F) {
return F->getName() == "printf" || F->getName() == "sscanf" ||
F->getName() == "fprintf" || F->getName() == "open" ||
F->getName() == "sprintf" || F->getName() == "fputs" ||
F->getName() == "fscanf" || F->getName() == "malloc" ||
F->getName() == "free";
}
static bool isResolvableFunc(const Function* callee) {
return !callee->isExternal() || isVAHackFn(callee);
}
static void GetAllCallees(const DSCallSite &CS,
std::vector<Function*> &Callees) {
if (CS.isDirectCall()) {
if (isResolvableFunc(CS.getCalleeFunc()))
Callees.push_back(CS.getCalleeFunc());
} else if (!CS.getCalleeNode()->isIncomplete()) {
// Get all callees.
unsigned OldSize = Callees.size();
CS.getCalleeNode()->addFullFunctionList(Callees);
// If any of the callees are unresolvable, remove the whole batch!
for (unsigned i = OldSize, e = Callees.size(); i != e; ++i)
if (!isResolvableFunc(Callees[i])) {
Callees.erase(Callees.begin()+OldSize, Callees.end());
return;
}
}
}
/// GetAllAuxCallees - Return a list containing all of the resolvable callees in
/// the aux list for the specified graph in the Callees vector.
static void GetAllAuxCallees(DSGraph &G, std::vector<Function*> &Callees) {
Callees.clear();
for (DSGraph::afc_iterator I = G.afc_begin(), E = G.afc_end(); I != E; ++I)
GetAllCallees(*I, Callees);
}
unsigned BUDataStructures::calculateGraphs(Function *F,
std::vector<Function*> &Stack,
unsigned &NextID,
hash_map<Function*, unsigned> &ValMap) {
assert(!ValMap.count(F) && "Shouldn't revisit functions!");
unsigned Min = NextID++, MyID = Min;
ValMap[F] = Min;
Stack.push_back(F);
// FIXME! This test should be generalized to be any function that we have
// already processed, in the case when there isn't a main or there are
// unreachable functions!
if (F->isExternal()) { // sprintf, fprintf, sscanf, etc...
// No callees!
Stack.pop_back();
ValMap[F] = ~0;
return Min;
}
DSGraph &Graph = getOrCreateGraph(F);
// Find all callee functions.
std::vector<Function*> CalleeFunctions;
GetAllAuxCallees(Graph, CalleeFunctions);
// The edges out of the current node are the call site targets...
for (unsigned i = 0, e = CalleeFunctions.size(); i != e; ++i) {
Function *Callee = CalleeFunctions[i];
unsigned M;
// Have we visited the destination function yet?
hash_map<Function*, unsigned>::iterator It = ValMap.find(Callee);
if (It == ValMap.end()) // No, visit it now.
M = calculateGraphs(Callee, Stack, NextID, ValMap);
else // Yes, get it's number.
M = It->second;
if (M < Min) Min = M;
}
assert(ValMap[F] == MyID && "SCC construction assumption wrong!");
if (Min != MyID)
return Min; // This is part of a larger SCC!
// If this is a new SCC, process it now.
if (Stack.back() == F) { // Special case the single "SCC" case here.
DEBUG(std::cerr << "Visiting single node SCC #: " << MyID << " fn: "
<< F->getName() << "\n");
Stack.pop_back();
DSGraph &G = getDSGraph(*F);
DEBUG(std::cerr << " [BU] Calculating graph for: " << F->getName()<< "\n");
calculateGraph(G);
DEBUG(std::cerr << " [BU] Done inlining: " << F->getName() << " ["
<< G.getGraphSize() << "+" << G.getAuxFunctionCalls().size()
<< "]\n");
if (MaxSCC < 1) MaxSCC = 1;
// Should we revisit the graph? Only do it if there are now new resolvable
// callees.
GetAllAuxCallees(Graph, CalleeFunctions);
if (!CalleeFunctions.empty()) {
ValMap.erase(F);
return calculateGraphs(F, Stack, NextID, ValMap);
} else {
ValMap[F] = ~0U;
}
return MyID;
} else {
// SCCFunctions - Keep track of the functions in the current SCC
//
std::vector<DSGraph*> SCCGraphs;
unsigned SCCSize = 1;
Function *NF = Stack.back();
ValMap[NF] = ~0U;
DSGraph &SCCGraph = getDSGraph(*NF);
// First thing first, collapse all of the DSGraphs into a single graph for
// the entire SCC. Splice all of the graphs into one and discard all of the
// old graphs.
//
while (NF != F) {
Stack.pop_back();
NF = Stack.back();
ValMap[NF] = ~0U;
DSGraph &NFG = getDSGraph(*NF);
// Update the Function -> DSG map.
for (DSGraph::retnodes_iterator I = NFG.retnodes_begin(),
E = NFG.retnodes_end(); I != E; ++I)
DSInfo[I->first] = &SCCGraph;
SCCGraph.spliceFrom(NFG);
delete &NFG;
++SCCSize;
}
Stack.pop_back();
std::cerr << "Calculating graph for SCC #: " << MyID << " of size: "
<< SCCSize << "\n";
// Compute the Max SCC Size.
if (MaxSCC < SCCSize)
MaxSCC = SCCSize;
// Clean up the graph before we start inlining a bunch again...
SCCGraph.removeDeadNodes(DSGraph::KeepUnreachableGlobals);
// Now that we have one big happy family, resolve all of the call sites in
// the graph...
calculateGraph(SCCGraph);
DEBUG(std::cerr << " [BU] Done inlining SCC [" << SCCGraph.getGraphSize()
<< "+" << SCCGraph.getAuxFunctionCalls().size() << "]\n");
std::cerr << "DONE with SCC #: " << MyID << "\n";
// We never have to revisit "SCC" processed functions...
return MyID;
}
return MyID; // == Min
}
// releaseMemory - If the pass pipeline is done with this pass, we can release
// our memory... here...
//
void BUDataStructures::releaseMyMemory() {
for (hash_map<Function*, DSGraph*>::iterator I = DSInfo.begin(),
E = DSInfo.end(); I != E; ++I) {
I->second->getReturnNodes().erase(I->first);
if (I->second->getReturnNodes().empty())
delete I->second;
}
// Empty map so next time memory is released, data structures are not
// re-deleted.
DSInfo.clear();
delete GlobalsGraph;
GlobalsGraph = 0;
}
DSGraph &BUDataStructures::CreateGraphForExternalFunction(const Function &Fn) {
Function *F = const_cast<Function*>(&Fn);
DSGraph *DSG = new DSGraph(GlobalECs, GlobalsGraph->getTargetData());
DSInfo[F] = DSG;
DSG->setGlobalsGraph(GlobalsGraph);
DSG->setPrintAuxCalls();
// Add function to the graph.
DSG->getReturnNodes().insert(std::make_pair(F, DSNodeHandle()));
if (F->getName() == "free") { // Taking the address of free.
// Free should take a single pointer argument, mark it as heap memory.
DSNode *N = new DSNode(0, DSG);
N->setHeapNodeMarker();
DSG->getNodeForValue(F->arg_begin()).mergeWith(N);
} else {
std::cerr << "Unrecognized external function: " << F->getName() << "\n";
abort();
}
return *DSG;
}
void BUDataStructures::calculateGraph(DSGraph &Graph) {
// If this graph contains the main function, clone the globals graph into this
// graph before we inline callees and other fun stuff.
bool ContainsMain = false;
DSGraph::ReturnNodesTy &ReturnNodes = Graph.getReturnNodes();
for (DSGraph::ReturnNodesTy::iterator I = ReturnNodes.begin(),
E = ReturnNodes.end(); I != E; ++I)
if (I->first->hasExternalLinkage() && I->first->getName() == "main") {
ContainsMain = true;
break;
}
// If this graph contains main, copy the contents of the globals graph over.
// Note that this is *required* for correctness. If a callee contains a use
// of a global, we have to make sure to link up nodes due to global-argument
// bindings.
if (ContainsMain) {
const DSGraph &GG = *Graph.getGlobalsGraph();
ReachabilityCloner RC(Graph, GG,
DSGraph::DontCloneCallNodes |
DSGraph::DontCloneAuxCallNodes);
// Clone the global nodes into this graph.
for (DSScalarMap::global_iterator I = GG.getScalarMap().global_begin(),
E = GG.getScalarMap().global_end(); I != E; ++I)
if (isa<GlobalVariable>(*I))
RC.getClonedNH(GG.getNodeForValue(*I));
}
// Move our call site list into TempFCs so that inline call sites go into the
// new call site list and doesn't invalidate our iterators!
std::list<DSCallSite> TempFCs;
std::list<DSCallSite> &AuxCallsList = Graph.getAuxFunctionCalls();
TempFCs.swap(AuxCallsList);
bool Printed = false;
std::vector<Function*> CalledFuncs;
while (!TempFCs.empty()) {
DSCallSite &CS = *TempFCs.begin();
CalledFuncs.clear();
// Fast path for noop calls. Note that we don't care about merging globals
// in the callee with nodes in the caller here.
if (CS.getRetVal().isNull() && CS.getNumPtrArgs() == 0) {
TempFCs.erase(TempFCs.begin());
continue;
} else if (CS.isDirectCall() && isVAHackFn(CS.getCalleeFunc())) {
TempFCs.erase(TempFCs.begin());
continue;
}
GetAllCallees(CS, CalledFuncs);
if (CalledFuncs.empty()) {
// Remember that we could not resolve this yet!
AuxCallsList.splice(AuxCallsList.end(), TempFCs, TempFCs.begin());
continue;
} else {
DSGraph *GI;
Instruction *TheCall = CS.getCallSite().getInstruction();
if (CalledFuncs.size() == 1) {
Function *Callee = CalledFuncs[0];
ActualCallees.insert(std::make_pair(TheCall, Callee));
// Get the data structure graph for the called function.
GI = &getDSGraph(*Callee); // Graph to inline
DEBUG(std::cerr << " Inlining graph for " << Callee->getName());
DEBUG(std::cerr << "[" << GI->getGraphSize() << "+"
<< GI->getAuxFunctionCalls().size() << "] into '"
<< Graph.getFunctionNames() << "' [" << Graph.getGraphSize() <<"+"
<< Graph.getAuxFunctionCalls().size() << "]\n");
Graph.mergeInGraph(CS, *Callee, *GI,
DSGraph::StripAllocaBit|DSGraph::DontCloneCallNodes);
++NumBUInlines;
} else {
if (!Printed)
std::cerr << "In Fns: " << Graph.getFunctionNames() << "\n";
std::cerr << " calls " << CalledFuncs.size()
<< " fns from site: " << CS.getCallSite().getInstruction()
<< " " << *CS.getCallSite().getInstruction();
std::cerr << " Fns =";
unsigned NumPrinted = 0;
for (std::vector<Function*>::iterator I = CalledFuncs.begin(),
E = CalledFuncs.end(); I != E; ++I) {
if (NumPrinted++ < 8) std::cerr << " " << (*I)->getName();
// Add the call edges to the call graph.
ActualCallees.insert(std::make_pair(TheCall, *I));
}
std::cerr << "\n";
// See if we already computed a graph for this set of callees.
std::sort(CalledFuncs.begin(), CalledFuncs.end());
std::pair<DSGraph*, std::vector<DSNodeHandle> > &IndCallGraph =
(*IndCallGraphMap)[CalledFuncs];
if (IndCallGraph.first == 0) {
std::vector<Function*>::iterator I = CalledFuncs.begin(),
E = CalledFuncs.end();
// Start with a copy of the first graph.
GI = IndCallGraph.first = new DSGraph(getDSGraph(**I), GlobalECs);
GI->setGlobalsGraph(Graph.getGlobalsGraph());
std::vector<DSNodeHandle> &Args = IndCallGraph.second;
// Get the argument nodes for the first callee. The return value is
// the 0th index in the vector.
GI->getFunctionArgumentsForCall(*I, Args);
// Merge all of the other callees into this graph.
for (++I; I != E; ++I) {
// If the graph already contains the nodes for the function, don't
// bother merging it in again.
if (!GI->containsFunction(*I)) {
GI->cloneInto(getDSGraph(**I));
++NumBUInlines;
}
std::vector<DSNodeHandle> NextArgs;
GI->getFunctionArgumentsForCall(*I, NextArgs);
unsigned i = 0, e = Args.size();
for (; i != e; ++i) {
if (i == NextArgs.size()) break;
Args[i].mergeWith(NextArgs[i]);
}
for (e = NextArgs.size(); i != e; ++i)
Args.push_back(NextArgs[i]);
}
// Clean up the final graph!
GI->removeDeadNodes(DSGraph::KeepUnreachableGlobals);
} else {
std::cerr << "***\n*** RECYCLED GRAPH ***\n***\n";
}
GI = IndCallGraph.first;
// Merge the unified graph into this graph now.
DEBUG(std::cerr << " Inlining multi callee graph "
<< "[" << GI->getGraphSize() << "+"
<< GI->getAuxFunctionCalls().size() << "] into '"
<< Graph.getFunctionNames() << "' [" << Graph.getGraphSize() <<"+"
<< Graph.getAuxFunctionCalls().size() << "]\n");
Graph.mergeInGraph(CS, IndCallGraph.second, *GI,
DSGraph::StripAllocaBit |
DSGraph::DontCloneCallNodes);
++NumBUInlines;
}
}
TempFCs.erase(TempFCs.begin());
}
// Recompute the Incomplete markers
Graph.maskIncompleteMarkers();
Graph.markIncompleteNodes(DSGraph::MarkFormalArgs);
// Delete dead nodes. Treat globals that are unreachable but that can
// reach live nodes as live.
Graph.removeDeadNodes(DSGraph::KeepUnreachableGlobals);
// When this graph is finalized, clone the globals in the graph into the
// globals graph to make sure it has everything, from all graphs.
DSScalarMap &MainSM = Graph.getScalarMap();
ReachabilityCloner RC(*GlobalsGraph, Graph, DSGraph::StripAllocaBit);
// Clone everything reachable from globals in the function graph into the
// globals graph.
for (DSScalarMap::global_iterator I = MainSM.global_begin(),
E = MainSM.global_end(); I != E; ++I)
RC.getClonedNH(MainSM[*I]);
//Graph.writeGraphToFile(std::cerr, "bu_" + F.getName());
}
static const Function *getFnForValue(const Value *V) {
if (const Instruction *I = dyn_cast<Instruction>(V))
return I->getParent()->getParent();
else if (const Argument *A = dyn_cast<Argument>(V))
return A->getParent();
else if (const BasicBlock *BB = dyn_cast<BasicBlock>(V))
return BB->getParent();
return 0;
}
/// deleteValue/copyValue - Interfaces to update the DSGraphs in the program.
/// These correspond to the interfaces defined in the AliasAnalysis class.
void BUDataStructures::deleteValue(Value *V) {
if (const Function *F = getFnForValue(V)) { // Function local value?
// If this is a function local value, just delete it from the scalar map!
getDSGraph(*F).getScalarMap().eraseIfExists(V);
return;
}
if (Function *F = dyn_cast<Function>(V)) {
assert(getDSGraph(*F).getReturnNodes().size() == 1 &&
"cannot handle scc's");
delete DSInfo[F];
DSInfo.erase(F);
return;
}
assert(!isa<GlobalVariable>(V) && "Do not know how to delete GV's yet!");
}
void BUDataStructures::copyValue(Value *From, Value *To) {
if (From == To) return;
if (const Function *F = getFnForValue(From)) { // Function local value?
// If this is a function local value, just delete it from the scalar map!
getDSGraph(*F).getScalarMap().copyScalarIfExists(From, To);
return;
}
if (Function *FromF = dyn_cast<Function>(From)) {
Function *ToF = cast<Function>(To);
assert(!DSInfo.count(ToF) && "New Function already exists!");
DSGraph *NG = new DSGraph(getDSGraph(*FromF), GlobalECs);
DSInfo[ToF] = NG;
assert(NG->getReturnNodes().size() == 1 && "Cannot copy SCC's yet!");
// Change the Function* is the returnnodes map to the ToF.
DSNodeHandle Ret = NG->retnodes_begin()->second;
NG->getReturnNodes().clear();
NG->getReturnNodes()[ToF] = Ret;
return;
}
if (const Function *F = getFnForValue(To)) {
DSGraph &G = getDSGraph(*F);
G.getScalarMap().copyScalarIfExists(From, To);
return;
}
std::cerr << *From;
std::cerr << *To;
assert(0 && "Do not know how to copy this yet!");
abort();
}