//===- DataStructure.cpp - Implement the core data structure analysis -----===//
+//
+// 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 core data structure functionality.
//
#include "llvm/iOther.h"
#include "llvm/DerivedTypes.h"
#include "llvm/Target/TargetData.h"
+#include "llvm/Assembly/Writer.h"
+#include "Support/Debug.h"
#include "Support/STLExtras.h"
#include "Support/Statistic.h"
#include "Support/Timer.h"
Statistic<> NumCallNodesMerged("dsnode", "Number of call nodes merged");
};
-namespace DS { // TODO: FIXME
- extern TargetData TD;
-}
using namespace DS;
DSNode *DSNodeHandle::HandleForwarding() const {
// DSNode copy constructor... do not copy over the referrers list!
DSNode::DSNode(const DSNode &N, DSGraph *G)
- : NumReferrers(0), Size(N.Size), ParentGraph(G), Ty(N.Ty),
- Links(N.Links), Globals(N.Globals), NodeType(N.NodeType) {
+ : NumReferrers(0), Size(N.Size), ParentGraph(G),
+ Ty(N.Ty), Links(N.Links), Globals(N.Globals), NodeType(N.NodeType) {
G->getNodes().push_back(this);
}
+/// getTargetData - Get the target data object used to construct this node.
+///
+const TargetData &DSNode::getTargetData() const {
+ return ParentGraph->getTargetData();
+}
+
void DSNode::assertOK() const {
assert((Ty != Type::VoidTy ||
Ty == Type::VoidTy && (Size == 0 ||
(NodeType & DSNode::Array))) &&
"Node not OK!");
+
+ assert(ParentGraph && "Node has no parent?");
+ const DSGraph::ScalarMapTy &SM = ParentGraph->getScalarMap();
+ for (unsigned i = 0, e = Globals.size(); i != e; ++i) {
+ assert(SM.find(Globals[i]) != SM.end());
+ assert(SM.find(Globals[i])->second.getNode() == this);
+ }
}
/// forwardNode - Mark this node as being obsolete, and all references to it
};
std::vector<StackState> Stack;
+ const TargetData &TD;
public:
- TypeElementWalker(const Type *T) {
+ TypeElementWalker(const Type *T, const TargetData &td) : TD(td) {
Stack.push_back(T);
StepToLeaf();
}
/// ElementTypesAreCompatible - Check to see if the specified types are
/// "physically" compatible. If so, return true, else return false. We only
-/// have to check the fields in T1: T2 may be larger than T1.
+/// have to check the fields in T1: T2 may be larger than T1. If AllowLargerT1
+/// is true, then we also allow a larger T1.
///
-static bool ElementTypesAreCompatible(const Type *T1, const Type *T2) {
- TypeElementWalker T1W(T1), T2W(T2);
+static bool ElementTypesAreCompatible(const Type *T1, const Type *T2,
+ bool AllowLargerT1, const TargetData &TD){
+ TypeElementWalker T1W(T1, TD), T2W(T2, TD);
while (!T1W.isDone() && !T2W.isDone()) {
if (T1W.getCurrentOffset() != T2W.getCurrentOffset())
T2W.StepToNextType();
}
- return T1W.isDone();
+ return AllowLargerT1 || T1W.isDone();
}
///
bool DSNode::mergeTypeInfo(const Type *NewTy, unsigned Offset,
bool FoldIfIncompatible) {
+ const TargetData &TD = getTargetData();
// Check to make sure the Size member is up-to-date. Size can be one of the
// following:
// Size = 0, Ty = Void: Nothing is known about this node.
if (Ty == Type::VoidTy) {
// If this is the first type that this node has seen, just accept it without
// question....
- assert(Offset == 0 && "Cannot have an offset into a void node!");
- assert(!isArray() && "This shouldn't happen!");
+ assert(Offset == 0 && !isArray() &&
+ "Cannot have an offset into a void node!");
Ty = NewTy;
NodeType &= ~Array;
if (WillBeArray) NodeType |= Array;
// just require each element in the node to be compatible.
if (NewTySize <= SubTypeSize && NewTySize && NewTySize < 256 &&
SubTypeSize && SubTypeSize < 256 &&
- ElementTypesAreCompatible(NewTy, SubType))
+ ElementTypesAreCompatible(NewTy, SubType, !isArray(), TD))
return false;
// Okay, so we found the leader type at the offset requested. Search the list
return false;
}
- DEBUG(std::cerr << "MergeTypeInfo Folding OrigTy: " << Ty
- << "\n due to:" << NewTy << " @ " << Offset << "!\n"
- << "SubType: " << SubType << "\n\n");
+ Module *M = 0;
+ if (getParentGraph()->getReturnNodes().size())
+ M = getParentGraph()->getReturnNodes().begin()->first->getParent();
+ DEBUG(std::cerr << "MergeTypeInfo Folding OrigTy: ";
+ WriteTypeSymbolic(std::cerr, Ty, M) << "\n due to:";
+ WriteTypeSymbolic(std::cerr, NewTy, M) << " @ " << Offset << "!\n"
+ << "SubType: ";
+ WriteTypeSymbolic(std::cerr, SubType, M) << "\n\n");
if (FoldIfIncompatible) foldNodeCompletely();
return true;
// Define here to avoid including iOther.h and BasicBlock.h in DSGraph.h
Function &DSCallSite::getCaller() const {
- return *Inst->getParent()->getParent();
+ return *Site.getInstruction()->getParent()->getParent();
}
}
-DSGraph::DSGraph(const DSGraph &G) : GlobalsGraph(0) {
+DSGraph::DSGraph(const DSGraph &G) : GlobalsGraph(0), TD(G.TD) {
PrintAuxCalls = false;
NodeMapTy NodeMap;
cloneInto(G, ScalarMap, ReturnNodes, NodeMap);
+ InlinedGlobals.clear(); // clear set of "up-to-date" globals
}
DSGraph::DSGraph(const DSGraph &G, NodeMapTy &NodeMap)
- : GlobalsGraph(0) {
+ : GlobalsGraph(0), TD(G.TD) {
PrintAuxCalls = false;
cloneInto(G, ScalarMap, ReturnNodes, NodeMap);
+ InlinedGlobals.clear(); // clear set of "up-to-date" globals
}
DSGraph::~DSGraph() {
FunctionCalls.clear();
AuxFunctionCalls.clear();
+ InlinedGlobals.clear();
ScalarMap.clear();
ReturnNodes.clear();
}
+/// cloneReachableNodes - Clone all reachable nodes from *Node into the
+/// current graph. This is a recursive function. The map OldNodeMap is a
+/// map from the original nodes to their clones.
+///
+void DSGraph::cloneReachableNodes(const DSNode* Node,
+ unsigned BitsToClear,
+ NodeMapTy& OldNodeMap,
+ NodeMapTy& CompletedNodeMap) {
+ if (CompletedNodeMap.find(Node) != CompletedNodeMap.end())
+ return;
+
+ DSNodeHandle& NH = OldNodeMap[Node];
+ if (NH.getNode() != NULL)
+ return;
+
+ // else Node has not yet been cloned: clone it and clear the specified bits
+ NH = new DSNode(*Node, this); // enters in OldNodeMap
+ NH.getNode()->maskNodeTypes(~BitsToClear);
+
+ // now recursively clone nodes pointed to by this node
+ for (unsigned i = 0, e = Node->getNumLinks(); i != e; ++i) {
+ const DSNodeHandle &Link = Node->getLink(i << DS::PointerShift);
+ if (const DSNode* nextNode = Link.getNode())
+ cloneReachableNodes(nextNode, BitsToClear, OldNodeMap, CompletedNodeMap);
+ }
+}
+
+void DSGraph::cloneReachableSubgraph(const DSGraph& G,
+ const hash_set<const DSNode*>& RootNodes,
+ NodeMapTy& OldNodeMap,
+ NodeMapTy& CompletedNodeMap,
+ unsigned CloneFlags) {
+ if (RootNodes.empty())
+ return;
+
+ assert(OldNodeMap.empty() && "Returned OldNodeMap should be empty!");
+ assert(&G != this && "Cannot clone graph into itself!");
+ assert((*RootNodes.begin())->getParentGraph() == &G &&
+ "Root nodes do not belong to this graph!");
+
+ // Remove alloca or mod/ref bits as specified...
+ unsigned BitsToClear = ((CloneFlags & StripAllocaBit)? DSNode::AllocaNode : 0)
+ | ((CloneFlags & StripModRefBits)? (DSNode::Modified | DSNode::Read) : 0)
+ | ((CloneFlags & StripIncompleteBit)? DSNode::Incomplete : 0);
+ BitsToClear |= DSNode::DEAD; // Clear dead flag...
+
+ // Clone all nodes reachable from each root node, using a recursive helper
+ for (hash_set<const DSNode*>::const_iterator I = RootNodes.begin(),
+ E = RootNodes.end(); I != E; ++I)
+ cloneReachableNodes(*I, BitsToClear, OldNodeMap, CompletedNodeMap);
+
+ // Merge the map entries in OldNodeMap and CompletedNodeMap to remap links
+ NodeMapTy MergedMap(OldNodeMap);
+ MergedMap.insert(CompletedNodeMap.begin(), CompletedNodeMap.end());
+
+ // Rewrite the links in the newly created nodes (the nodes in OldNodeMap)
+ // to point into the current graph. MergedMap gives the full mapping.
+ for (NodeMapTy::iterator I=OldNodeMap.begin(), E=OldNodeMap.end(); I!= E; ++I)
+ I->second.getNode()->remapLinks(MergedMap);
+
+ // Now merge cloned global nodes with their copies in the current graph
+ // Just look through OldNodeMap to find such nodes!
+ for (NodeMapTy::iterator I=OldNodeMap.begin(), E=OldNodeMap.end(); I!= E; ++I)
+ if (I->first->isGlobalNode()) {
+ DSNodeHandle &GClone = I->second;
+ assert(GClone.getNode() != NULL && "NULL node in OldNodeMap?");
+ const std::vector<GlobalValue*> &Globals = I->first->getGlobals();
+ for (unsigned gi = 0, ge = Globals.size(); gi != ge; ++gi) {
+ DSNodeHandle &GH = ScalarMap[Globals[gi]];
+ GH.mergeWith(GClone);
+ }
+ }
+}
+
+
+/// updateFromGlobalGraph - This function rematerializes global nodes and
+/// nodes reachable from them from the globals graph into the current graph.
+/// It invokes cloneReachableSubgraph, using the globals in the current graph
+/// as the roots. It also uses the vector InlinedGlobals to avoid cloning and
+/// merging globals that are already up-to-date in the current graph. In
+/// practice, in the TD pass, this is likely to be a large fraction of the
+/// live global nodes in each function (since most live nodes are likely to
+/// have been brought up-to-date in at _some_ caller or callee).
+///
+void DSGraph::updateFromGlobalGraph() {
+
+ // Use a map to keep track of the mapping between nodes in the globals graph
+ // and this graph for up-to-date global nodes, which do not need to be cloned.
+ NodeMapTy CompletedMap;
+
+ // Put the live, non-up-to-date global nodes into a set and the up-to-date
+ // ones in the map above, mapping node in GlobalsGraph to the up-to-date node.
+ hash_set<const DSNode*> GlobalNodeSet;
+ for (ScalarMapTy::const_iterator I = getScalarMap().begin(),
+ E = getScalarMap().end(); I != E; ++I)
+ if (GlobalValue* GV = dyn_cast<GlobalValue>(I->first)) {
+ DSNode* GNode = I->second.getNode();
+ assert(GNode && "No node for live global in current Graph?");
+ if (const DSNode* GGNode = GlobalsGraph->ScalarMap[GV].getNode())
+ if (InlinedGlobals.count(GV) == 0) // GNode is not up-to-date
+ GlobalNodeSet.insert(GGNode);
+ else { // GNode is up-to-date
+ CompletedMap[GGNode] = I->second;
+ assert(GGNode->getNumLinks() == GNode->getNumLinks() &&
+ "Links dont match in a node that is supposed to be up-to-date?"
+ "\nremapLinks() will not work if the links don't match!");
+ }
+ }
+
+ // Clone the subgraph reachable from the vector of nodes in GlobalNodes
+ // and merge the cloned global nodes with the corresponding ones, if any.
+ NodeMapTy OldNodeMap;
+ cloneReachableSubgraph(*GlobalsGraph, GlobalNodeSet, OldNodeMap,CompletedMap);
+
+ // Merging global nodes leaves behind unused nodes: get rid of them now.
+ OldNodeMap.clear(); // remove references before dead node cleanup
+ CompletedMap.clear(); // remove references before dead node cleanup
+ removeTriviallyDeadNodes();
+}
+
/// cloneInto - Clone the specified DSGraph into the current graph. The
/// translated ScalarMap for the old function is filled into the OldValMap
/// member, and the translated ReturnNodes map is returned into ReturnNodes.
Nodes.reserve(FN+G.Nodes.size());
// Remove alloca or mod/ref bits as specified...
- unsigned BitsToClear =((CloneFlags & StripAllocaBit) ? DSNode::AllocaNode : 0)
- | ((CloneFlags & StripModRefBits) ? (DSNode::Modified | DSNode::Read) : 0);
+ unsigned BitsToClear = ((CloneFlags & StripAllocaBit)? DSNode::AllocaNode : 0)
+ | ((CloneFlags & StripModRefBits)? (DSNode::Modified | DSNode::Read) : 0)
+ | ((CloneFlags & StripIncompleteBit)? DSNode::Incomplete : 0);
BitsToClear |= DSNode::DEAD; // Clear dead flag...
for (unsigned i = 0, e = G.Nodes.size(); i != e; ++i) {
DSNode *Old = G.Nodes[i];
I->second.getOffset()+MappedNode.getOffset()));
// If this is a global, add the global to this fn or merge if already exists
- if (isa<GlobalValue>(I->first))
- ScalarMap[I->first].mergeWith(H);
+ if (GlobalValue* GV = dyn_cast<GlobalValue>(I->first)) {
+ ScalarMap[GV].mergeWith(H);
+ InlinedGlobals.insert(GV);
+ }
}
if (!(CloneFlags & DontCloneCallNodes)) {
}
if (!(CloneFlags & DontCloneAuxCallNodes)) {
- // Copy the auxillary function calls list...
+ // Copy the auxiliary function calls list...
unsigned FC = AuxFunctionCalls.size(); // FirstCall
AuxFunctionCalls.reserve(FC+G.AuxFunctionCalls.size());
for (unsigned i = 0, ei = G.AuxFunctionCalls.size(); i != ei; ++i)
// structure graph. Strip locals and don't copy the list of callers
ReturnNodesTy OldRetNodes;
cloneInto(Graph, OldValMap, OldRetNodes, OldNodeMap, CloneFlags);
+
+ // We need to map the arguments for the function to the cloned nodes old
+ // argument values. Do this now.
RetVal = OldRetNodes[&F];
ScalarMap = &OldValMap;
} else {
}
}
+/// getCallSiteForArguments - Get the arguments and return value bindings for
+/// the specified function in the current graph.
+///
+DSCallSite DSGraph::getCallSiteForArguments(Function &F) const {
+ std::vector<DSNodeHandle> Args;
+
+ for (Function::aiterator I = F.abegin(), E = F.aend(); I != E; ++I)
+ if (isPointerType(I->getType()))
+ Args.push_back(getScalarMap().find(I)->second);
+
+ return DSCallSite(CallSite(), getReturnNodeFor(F), &F, Args);
+}
+
+
// markIncompleteNodes - Mark the specified node as having contents that are not
// known with the current analysis we have performed. Because a node makes all
// Actually mark the node
N->setIncompleteMarker();
- // Recusively process children...
+ // Recursively process children...
for (unsigned i = 0, e = N->getSize(); i < e; i += DS::PointerSize)
if (DSNode *DSN = N->getLink(i).getNode())
markIncompleteNode(DSN);
LastCalleeContainsExternalFunction = LastCalleeFunc->isExternal();
}
-#if 0
+#if 1
if (LastCalleeContainsExternalFunction ||
// This should be more than enough context sensitivity!
// FIXME: Evaluate how many times this is tripped!
removeIdenticalCalls(FunctionCalls);
removeIdenticalCalls(AuxFunctionCalls);
+ // Loop over all of the nodes in the graph, calling getNode on each field.
+ // This will cause all nodes to update their forwarding edges, causing
+ // forwarded nodes to be delete-able.
+ for (unsigned i = 0, e = Nodes.size(); i != e; ++i) {
+ DSNode *N = Nodes[i];
+ for (unsigned l = 0, e = N->getNumLinks(); l != e; ++l)
+ N->getLink(l*N->getPointerSize()).getNode();
+ }
+
+ // Likewise, forward any edges from the scalar nodes...
+ for (ScalarMapTy::iterator I = ScalarMap.begin(), E = ScalarMap.end();
+ I != E; ++I)
+ I->second.getNode();
+
+ bool isGlobalsGraph = !GlobalsGraph;
+
for (unsigned i = 0; i != Nodes.size(); ++i) {
DSNode *Node = Nodes[i];
+
+ // Do not remove *any* global nodes in the globals graph.
+ // This is a special case because such nodes may not have I, M, R flags set.
+ if (Node->isGlobalNode() && isGlobalsGraph)
+ continue;
+
if (Node->isComplete() && !Node->isModified() && !Node->isRead()) {
// This is a useless node if it has no mod/ref info (checked above),
// outgoing edges (which it cannot, as it is not modified in this
Node->makeNodeDead();
}
}
+
+#ifdef SANER_CODE_FOR_CHECKING_IF_ALL_REFERRERS_ARE_FROM_SCALARMAP
+ //
+ // *** It seems to me that we should be able to simply check if
+ // *** there are fewer or equal #referrers as #globals and make
+ // *** sure that all those referrers are in the scalar map?
+ //
+ if (Node->getNumReferrers() <= Node->getGlobals().size()) {
+ const std::vector<GlobalValue*> &Globals = Node->getGlobals();
+
+#ifndef NDEBUG
+ // Loop through and make sure all of the globals are referring directly
+ // to the node...
+ for (unsigned j = 0, e = Globals.size(); j != e; ++j) {
+ DSNode *N = ScalarMap.find(Globals[j])->second.getNode();
+ assert(N == Node && "ScalarMap doesn't match globals list!");
+ }
+#endif
+
+ // Make sure NumReferrers still agrees. The node is truly dead.
+ assert(Node->getNumReferrers() == Globals.size());
+ for (unsigned j = 0, e = Globals.size(); j != e; ++j)
+ ScalarMap.erase(Globals[j]);
+ Node->makeNodeDead();
+ }
+#endif
}
if (Node->getNodeFlags() == 0 && Node->hasNoReferrers()) {
// marked as alive...
//
static bool CanReachAliveNodes(DSNode *N, hash_set<DSNode*> &Alive,
- hash_set<DSNode*> &Visited) {
+ hash_set<DSNode*> &Visited,
+ bool IgnoreGlobals) {
if (N == 0) return false;
assert(N->getForwardNode() == 0 && "Cannot mark a forwarded node!");
+ // If this is a global node, it will end up in the globals graph anyway, so we
+ // don't need to worry about it.
+ if (IgnoreGlobals && N->isGlobalNode()) return false;
+
// If we know that this node is alive, return so!
if (Alive.count(N)) return true;
Visited.insert(N); // No recursion, insert into Visited...
for (unsigned i = 0, e = N->getSize(); i < e; i += DS::PointerSize)
- if (CanReachAliveNodes(N->getLink(i).getNode(), Alive, Visited)) {
+ if (CanReachAliveNodes(N->getLink(i).getNode(), Alive, Visited,
+ IgnoreGlobals)) {
N->markReachableNodes(Alive);
return true;
}
// alive nodes.
//
static bool CallSiteUsesAliveArgs(DSCallSite &CS, hash_set<DSNode*> &Alive,
- hash_set<DSNode*> &Visited) {
- if (CanReachAliveNodes(CS.getRetVal().getNode(), Alive, Visited))
+ hash_set<DSNode*> &Visited,
+ bool IgnoreGlobals) {
+ if (CanReachAliveNodes(CS.getRetVal().getNode(), Alive, Visited,
+ IgnoreGlobals))
return true;
if (CS.isIndirectCall() &&
- CanReachAliveNodes(CS.getCalleeNode(), Alive, Visited))
+ CanReachAliveNodes(CS.getCalleeNode(), Alive, Visited, IgnoreGlobals))
return true;
for (unsigned i = 0, e = CS.getNumPtrArgs(); i != e; ++i)
- if (CanReachAliveNodes(CS.getPtrArg(i).getNode(), Alive, Visited))
+ if (CanReachAliveNodes(CS.getPtrArg(i).getNode(), Alive, Visited,
+ IgnoreGlobals))
return true;
return false;
}
// inlining graphs.
//
void DSGraph::removeDeadNodes(unsigned Flags) {
+ DEBUG(AssertGraphOK(); GlobalsGraph->AssertGraphOK());
+
// Reduce the amount of work we have to do... remove dummy nodes left over by
// merging...
removeTriviallyDeadNodes();
- // FIXME: Merge nontrivially identical call nodes...
+ // FIXME: Merge non-trivially identical call nodes...
// Alive - a set that holds all nodes found to be reachable/alive.
hash_set<DSNode*> Alive;
for (ScalarMapTy::iterator I = ScalarMap.begin(), E = ScalarMap.end(); I !=E;)
if (isa<GlobalValue>(I->first)) { // Keep track of global nodes
assert(I->second.getNode() && "Null global node?");
+ assert(I->second.getNode()->isGlobalNode() && "Should be a global node!");
GlobalNodes.push_back(std::make_pair(I->first, I->second.getNode()));
++I;
} else {
// these, prune the scalar pointing to it.
//
DSNode *N = I->second.getNode();
- if (N->isUnknownNode() && !isa<Argument>(I->first)) {
+ if (N->getNodeFlags() == DSNode::UnknownNode && !isa<Argument>(I->first)){
ScalarMap.erase(I++);
} else {
I->second.getNode()->markReachableNodes(Alive);
for (unsigned i = 0, e = FunctionCalls.size(); i != e; ++i)
FunctionCalls[i].markReachableNodes(Alive);
+ // Copy and merge all information about globals to the GlobalsGraph
+ // if this is not a final pass (where unreachable globals are removed)
+ NodeMapTy GlobalNodeMap;
+ hash_set<const DSNode*> GlobalNodeSet;
+
+ for (std::vector<std::pair<Value*, DSNode*> >::const_iterator
+ I = GlobalNodes.begin(), E = GlobalNodes.end(); I != E; ++I)
+ GlobalNodeSet.insert(I->second); // put global nodes into a set
+
+ // Now find globals and aux call nodes that are already live or reach a live
+ // value (which makes them live in turn), and continue till no more are found.
+ //
bool Iterate;
hash_set<DSNode*> Visited;
std::vector<unsigned char> AuxFCallsAlive(AuxFunctionCalls.size());
do {
Visited.clear();
- // If any global nodes points to a non-global that is "alive", the global is
+ // If any global node points to a non-global that is "alive", the global is
// "alive" as well... Remove it from the GlobalNodes list so we only have
// unreachable globals in the list.
//
Iterate = false;
- for (unsigned i = 0; i != GlobalNodes.size(); ++i)
- if (CanReachAliveNodes(GlobalNodes[i].second, Alive, Visited)) {
- std::swap(GlobalNodes[i--], GlobalNodes.back()); // Move to end to erase
- GlobalNodes.pop_back(); // Erase efficiently
- Iterate = true;
- }
-
+ if (!(Flags & DSGraph::RemoveUnreachableGlobals))
+ for (unsigned i = 0; i != GlobalNodes.size(); ++i)
+ if (CanReachAliveNodes(GlobalNodes[i].second, Alive, Visited,
+ Flags & DSGraph::RemoveUnreachableGlobals)) {
+ std::swap(GlobalNodes[i--], GlobalNodes.back()); // Move to end to...
+ GlobalNodes.pop_back(); // erase efficiently
+ Iterate = true;
+ }
+
+ // Mark only unresolvable call nodes for moving to the GlobalsGraph since
+ // call nodes that get resolved will be difficult to remove from that graph.
+ // The final unresolved call nodes must be handled specially at the end of
+ // the BU pass (i.e., in main or other roots of the call graph).
for (unsigned i = 0, e = AuxFunctionCalls.size(); i != e; ++i)
if (!AuxFCallsAlive[i] &&
- CallSiteUsesAliveArgs(AuxFunctionCalls[i], Alive, Visited)) {
+ (AuxFunctionCalls[i].isIndirectCall()
+ || CallSiteUsesAliveArgs(AuxFunctionCalls[i], Alive, Visited,
+ Flags & DSGraph::RemoveUnreachableGlobals))) {
AuxFunctionCalls[i].markReachableNodes(Alive);
AuxFCallsAlive[i] = true;
Iterate = true;
}
} while (Iterate);
- // Remove all dead aux function calls...
+ // Move dead aux function calls to the end of the list
unsigned CurIdx = 0;
for (unsigned i = 0, e = AuxFunctionCalls.size(); i != e; ++i)
if (AuxFCallsAlive[i])
AuxFunctionCalls[CurIdx++].swap(AuxFunctionCalls[i]);
+
+ // Copy and merge all global nodes and dead aux call nodes into the
+ // GlobalsGraph, and all nodes reachable from those nodes
+ //
+ if (!(Flags & DSGraph::RemoveUnreachableGlobals)) {
+
+ // First, add the dead aux call nodes to the set of root nodes for cloning
+ // -- return value at this call site, if any
+ // -- actual arguments passed at this call site
+ // -- callee node at this call site, if this is an indirect call
+ for (unsigned i = CurIdx, e = AuxFunctionCalls.size(); i != e; ++i) {
+ if (const DSNode* RetNode = AuxFunctionCalls[i].getRetVal().getNode())
+ GlobalNodeSet.insert(RetNode);
+ for (unsigned j=0, N=AuxFunctionCalls[i].getNumPtrArgs(); j < N; ++j)
+ if (const DSNode* ArgTarget=AuxFunctionCalls[i].getPtrArg(j).getNode())
+ GlobalNodeSet.insert(ArgTarget);
+ if (AuxFunctionCalls[i].isIndirectCall())
+ GlobalNodeSet.insert(AuxFunctionCalls[i].getCalleeNode());
+ }
+
+ // There are no "pre-completed" nodes so use any empty map for those.
+ // Strip all alloca bits since the current function is only for the BU pass.
+ // Strip all incomplete bits since they are short-lived properties and they
+ // will be correctly computed when rematerializing nodes into the functions.
+ //
+ NodeMapTy CompletedMap;
+ GlobalsGraph->cloneReachableSubgraph(*this, GlobalNodeSet,
+ GlobalNodeMap, CompletedMap,
+ (DSGraph::StripAllocaBit |
+ DSGraph::StripIncompleteBit));
+ }
+
+ // Remove all dead aux function calls...
if (!(Flags & DSGraph::RemoveUnreachableGlobals)) {
assert(GlobalsGraph && "No globals graph available??");
- // Move the unreachable call nodes to the globals graph...
- GlobalsGraph->AuxFunctionCalls.insert(GlobalsGraph->AuxFunctionCalls.end(),
- AuxFunctionCalls.begin()+CurIdx,
- AuxFunctionCalls.end());
+
+ // Copy the unreachable call nodes to the globals graph, updating
+ // their target pointers using the GlobalNodeMap
+ for (unsigned i = CurIdx, e = AuxFunctionCalls.size(); i != e; ++i)
+ GlobalsGraph->AuxFunctionCalls.push_back(DSCallSite(AuxFunctionCalls[i],
+ GlobalNodeMap));
}
// Crop all the useless ones out...
AuxFunctionCalls.erase(AuxFunctionCalls.begin()+CurIdx,
AuxFunctionCalls.end());
- // At this point, any nodes which are visited, but not alive, are nodes which
- // should be moved to the globals graph. Loop over all nodes, eliminating
- // completely unreachable nodes, and moving visited nodes to the globals graph
+ // We are finally done with the GlobalNodeMap so we can clear it and
+ // then get rid of unused nodes in the GlobalsGraph produced by merging.
+ GlobalNodeMap.clear();
+ GlobalsGraph->removeTriviallyDeadNodes();
+
+ // At this point, any nodes which are visited, but not alive, are nodes
+ // which can be removed. Loop over all nodes, eliminating completely
+ // unreachable nodes.
//
std::vector<DSNode*> DeadNodes;
DeadNodes.reserve(Nodes.size());
DSNode *N = Nodes[i];
Nodes[i--] = Nodes.back(); // move node to end of vector
Nodes.pop_back(); // Erase node from alive list.
- if (!(Flags & DSGraph::RemoveUnreachableGlobals) && // Not in TD pass
- Visited.count(N)) { // Visited but not alive?
- GlobalsGraph->Nodes.push_back(N); // Move node to globals graph
- N->setParentGraph(GlobalsGraph);
- } else { // Otherwise, delete the node
- assert((!N->isGlobalNode() ||
- (Flags & DSGraph::RemoveUnreachableGlobals))
- && "Killing a global?");
- //std::cerr << "[" << i+1 << "/" << DeadNodes.size()
- // << "] Node is dead: "; N->dump();
- DeadNodes.push_back(N);
- N->dropAllReferences();
- }
+ DeadNodes.push_back(N);
+ N->dropAllReferences();
} else {
assert(Nodes[i]->getForwardNode() == 0 && "Alive forwarded node?");
}
- // Now that the nodes have either been deleted or moved to the globals graph,
- // loop over the scalarmap, updating the entries for globals...
- //
- if (!(Flags & DSGraph::RemoveUnreachableGlobals)) { // Not in the TD pass?
- // In this array we start the remapping, which can cause merging. Because
- // of this, the DSNode pointers in GlobalNodes may be invalidated, so we
- // must always go through the ScalarMap (which contains DSNodeHandles [which
- // cannot be invalidated by merging]).
- //
- for (unsigned i = 0, e = GlobalNodes.size(); i != e; ++i) {
- Value *G = GlobalNodes[i].first;
- ScalarMapTy::iterator I = ScalarMap.find(G);
- assert(I != ScalarMap.end() && "Global not in scalar map anymore?");
- assert(I->second.getNode() && "Global not pointing to anything?");
- assert(!Alive.count(I->second.getNode()) && "Node is alive??");
- GlobalsGraph->ScalarMap[G].mergeWith(I->second);
- assert(GlobalsGraph->ScalarMap[G].getNode() &&
- "Global not pointing to anything?");
- ScalarMap.erase(I);
- }
-
- // Merging leaves behind silly nodes, we remove them to avoid polluting the
- // globals graph.
- if (!GlobalNodes.empty())
- GlobalsGraph->removeTriviallyDeadNodes();
- } else {
- // If we are in the top-down pass, remove all unreachable globals from the
- // ScalarMap...
- for (unsigned i = 0, e = GlobalNodes.size(); i != e; ++i)
+ // Remove all unreachable globals from the ScalarMap.
+ // If flag RemoveUnreachableGlobals is set, GlobalNodes has only dead nodes.
+ // In either case, the dead nodes will not be in the set Alive.
+ for (unsigned i = 0, e = GlobalNodes.size(); i != e; ++i) {
+ assert(((Flags & DSGraph::RemoveUnreachableGlobals) ||
+ !Alive.count(GlobalNodes[i].second)) && "huh? non-dead global");
+ if (!Alive.count(GlobalNodes[i].second))
ScalarMap.erase(GlobalNodes[i].first);
}
- // Loop over all of the dead nodes now, deleting them since their referrer
- // count is zero.
+ // Delete all dead nodes now since their referrer counts are zero.
for (unsigned i = 0, e = DeadNodes.size(); i != e; ++i)
delete DeadNodes[i];
void DSGraph::AssertGraphOK() const {
for (unsigned i = 0, e = Nodes.size(); i != e; ++i)
Nodes[i]->assertOK();
- return; // FIXME: remove
+
for (ScalarMapTy::const_iterator I = ScalarMap.begin(),
E = ScalarMap.end(); I != E; ++I) {
assert(I->second.getNode() && "Null node in scalarmap!");
AssertCallNodesInGraph();
AssertAuxCallNodesInGraph();
}
+
+/// mergeInGlobalsGraph - This method is useful for clients to incorporate the
+/// globals graph into the DS, BU or TD graph for a function. This code retains
+/// all globals, i.e., does not delete unreachable globals after they are
+/// inlined.
+///
+void DSGraph::mergeInGlobalsGraph() {
+ NodeMapTy GlobalNodeMap;
+ ScalarMapTy OldValMap;
+ ReturnNodesTy OldRetNodes;
+ cloneInto(*GlobalsGraph, OldValMap, OldRetNodes, GlobalNodeMap,
+ DSGraph::KeepAllocaBit | DSGraph::DontCloneCallNodes |
+ DSGraph::DontCloneAuxCallNodes);
+
+ // Now merge existing global nodes in the GlobalsGraph with their copies
+ for (ScalarMapTy::iterator I = ScalarMap.begin(), E = ScalarMap.end();
+ I != E; ++I)
+ if (isa<GlobalValue>(I->first)) { // Found a global node
+ DSNodeHandle &GH = I->second;
+ DSNodeHandle &GGNodeH = GlobalsGraph->getScalarMap()[I->first];
+ GH.mergeWith(GlobalNodeMap[GGNodeH.getNode()]);
+ }
+
+ // Merging leaves behind unused nodes: get rid of them now.
+ GlobalNodeMap.clear();
+ OldValMap.clear();
+ OldRetNodes.clear();
+ removeTriviallyDeadNodes();
+}