//===- 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/Analysis/DSGraph.h"
+#include "llvm/Analysis/DataStructure/DSGraphTraits.h"
#include "llvm/Function.h"
-#include "llvm/iOther.h"
+#include "llvm/GlobalVariable.h"
+#include "llvm/Instructions.h"
#include "llvm/DerivedTypes.h"
#include "llvm/Target/TargetData.h"
-#include "Support/STLExtras.h"
-#include "Support/Statistic.h"
-#include "Support/Timer.h"
+#include "llvm/Assembly/Writer.h"
+#include "llvm/Support/CommandLine.h"
+#include "llvm/Support/Debug.h"
+#include "llvm/ADT/DepthFirstIterator.h"
+#include "llvm/ADT/STLExtras.h"
+#include "llvm/ADT/Statistic.h"
+#include "llvm/Support/Timer.h"
#include <algorithm>
+using namespace llvm;
namespace {
- Statistic<> NumFolds ("dsnode", "Number of nodes completely folded");
- Statistic<> NumCallNodesMerged("dsnode", "Number of call nodes merged");
+ Statistic<> NumFolds ("dsa", "Number of nodes completely folded");
+ Statistic<> NumCallNodesMerged("dsa", "Number of call nodes merged");
+ Statistic<> NumNodeAllocated ("dsa", "Number of nodes allocated");
+ Statistic<> NumDNE ("dsa", "Number of nodes removed by reachability");
+ Statistic<> NumTrivialDNE ("dsa", "Number of nodes trivially removed");
+ Statistic<> NumTrivialGlobalDNE("dsa", "Number of globals trivially removed");
};
-namespace DS { // TODO: FIXME
- extern TargetData TD;
-}
+#if 1
+#define TIME_REGION(VARNAME, DESC) \
+ NamedRegionTimer VARNAME(DESC)
+#else
+#define TIME_REGION(VARNAME, DESC)
+#endif
+
using namespace DS;
DSNode *DSNodeHandle::HandleForwarding() const {
- assert(!N->ForwardNH.isNull() && "Can only be invoked if forwarding!");
+ assert(N->isForwarding() && "Can only be invoked if forwarding!");
// Handle node forwarding here!
DSNode *Next = N->ForwardNH.getNode(); // Cause recursive shrinkage
: NumReferrers(0), Size(0), ParentGraph(G), Ty(Type::VoidTy), NodeType(0) {
// Add the type entry if it is specified...
if (T) mergeTypeInfo(T, 0);
- G->getNodes().push_back(this);
+ if (G) G->addNode(this);
+ ++NumNodeAllocated;
}
// 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) {
- G->getNodes().push_back(this);
+DSNode::DSNode(const DSNode &N, DSGraph *G, bool NullLinks)
+ : NumReferrers(0), Size(N.Size), ParentGraph(G),
+ Ty(N.Ty), NodeType(N.NodeType) {
+ if (!NullLinks) {
+ Links = N.Links;
+ Globals = N.Globals;
+ } else
+ Links.resize(N.Links.size()); // Create the appropriate number of null links
+ G->addNode(this);
+ ++NumNodeAllocated;
+}
+
+/// getTargetData - Get the target data object used to construct this node.
+///
+const TargetData &DSNode::getTargetData() const {
+ return ParentGraph->getTargetData();
}
void DSNode::assertOK() const {
Ty == Type::VoidTy && (Size == 0 ||
(NodeType & DSNode::Array))) &&
"Node not OK!");
+
+ assert(ParentGraph && "Node has no parent?");
+ const DSScalarMap &SM = ParentGraph->getScalarMap();
+ for (unsigned i = 0, e = Globals.size(); i != e; ++i) {
+ assert(SM.count(Globals[i]));
+ assert(SM.find(Globals[i])->second.getNode() == this);
+ }
}
/// forwardNode - Mark this node as being obsolete, and all references to it
if (To->Size <= 1) Offset = 0;
assert((Offset < To->Size || (Offset == To->Size && Offset == 0)) &&
"Forwarded offset is wrong!");
- ForwardNH.setNode(To);
- ForwardNH.setOffset(Offset);
+ ForwardNH.setTo(To, Offset);
NodeType = DEAD;
Size = 0;
Ty = Type::VoidTy;
+
+ // Remove this node from the parent graph's Nodes list.
+ ParentGraph->unlinkNode(this);
+ ParentGraph = 0;
}
// addGlobal - Add an entry for a global value to the Globals list. This also
++NumFolds;
- // Create the node we are going to forward to...
- DSNode *DestNode = new DSNode(0, ParentGraph);
- DestNode->NodeType = NodeType|DSNode::Array;
- DestNode->Ty = Type::VoidTy;
- DestNode->Size = 1;
- DestNode->Globals.swap(Globals);
-
- // Start forwarding to the destination node...
- forwardNode(DestNode, 0);
-
- if (Links.size()) {
- DestNode->Links.push_back(Links[0]);
- DSNodeHandle NH(DestNode);
-
- // If we have links, merge all of our outgoing links together...
- for (unsigned i = Links.size()-1; i != 0; --i)
- NH.getNode()->Links[0].mergeWith(Links[i]);
- Links.clear();
+ // If this node has a size that is <= 1, we don't need to create a forwarding
+ // node.
+ if (getSize() <= 1) {
+ NodeType |= DSNode::Array;
+ Ty = Type::VoidTy;
+ Size = 1;
+ assert(Links.size() <= 1 && "Size is 1, but has more links?");
+ Links.resize(1);
} else {
- DestNode->Links.resize(1);
+ // Create the node we are going to forward to. This is required because
+ // some referrers may have an offset that is > 0. By forcing them to
+ // forward, the forwarder has the opportunity to correct the offset.
+ DSNode *DestNode = new DSNode(0, ParentGraph);
+ DestNode->NodeType = NodeType|DSNode::Array;
+ DestNode->Ty = Type::VoidTy;
+ DestNode->Size = 1;
+ DestNode->Globals.swap(Globals);
+
+ // Start forwarding to the destination node...
+ forwardNode(DestNode, 0);
+
+ if (!Links.empty()) {
+ DestNode->Links.reserve(1);
+
+ DSNodeHandle NH(DestNode);
+ DestNode->Links.push_back(Links[0]);
+
+ // If we have links, merge all of our outgoing links together...
+ for (unsigned i = Links.size()-1; i != 0; --i)
+ NH.getNode()->Links[0].mergeWith(Links[i]);
+ Links.clear();
+ } else {
+ DestNode->Links.resize(1);
+ }
}
}
return getSize() == 1 && Ty == Type::VoidTy && isArray();
}
-
namespace {
/// TypeElementWalker Class - Used for implementation of physical subtyping...
///
};
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();
}
StackState &SS = Stack.back();
if (const StructType *ST = dyn_cast<StructType>(SS.Ty)) {
++SS.Idx;
- if (SS.Idx != ST->getElementTypes().size()) {
+ if (SS.Idx != ST->getNumElements()) {
const StructLayout *SL = TD.getStructLayout(ST);
SS.Offset += SL->MemberOffsets[SS.Idx]-SL->MemberOffsets[SS.Idx-1];
return;
while (!Stack.empty() && !Stack.back().Ty->isFirstClassType()) {
StackState &SS = Stack.back();
if (const StructType *ST = dyn_cast<StructType>(SS.Ty)) {
- if (ST->getElementTypes().empty()) {
+ if (ST->getNumElements() == 0) {
assert(SS.Idx == 0);
PopStackAndAdvance();
} else {
// Step into the structure...
- assert(SS.Idx < ST->getElementTypes().size());
+ assert(SS.Idx < ST->getNumElements());
const StructLayout *SL = TD.getStructLayout(ST);
- Stack.push_back(StackState(ST->getElementTypes()[SS.Idx],
+ Stack.push_back(StackState(ST->getElementType(SS.Idx),
SS.Offset+SL->MemberOffsets[SS.Idx]));
}
} else {
}
}
};
-}
+} // end anonymous namespace
/// 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;
while (O < Offset) {
assert(Offset-O < TD.getTypeSize(SubType) && "Offset out of range!");
- switch (SubType->getPrimitiveID()) {
+ switch (SubType->getTypeID()) {
case Type::StructTyID: {
const StructType *STy = cast<StructType>(SubType);
const StructLayout &SL = *TD.getStructLayout(STy);
/* empty */;
// The offset we are looking for must be in the i'th element...
- SubType = STy->getElementTypes()[i];
+ SubType = STy->getElementType(i);
O += SL.MemberOffsets[i];
break;
}
// If we found our type exactly, early exit
if (SubType == NewTy) return false;
+ // Differing function types don't require us to merge. They are not values
+ // anyway.
+ if (isa<FunctionType>(SubType) &&
+ isa<FunctionType>(NewTy)) return false;
+
unsigned SubTypeSize = SubType->isSized() ? TD.getTypeSize(SubType) : 0;
// Ok, we are getting desperate now. Check for physical subtyping, where we
// 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
const Type *NextSubType = 0;
unsigned NextSubTypeSize = 0;
unsigned NextPadSize = 0;
- switch (SubType->getPrimitiveID()) {
+ switch (SubType->getTypeID()) {
case Type::StructTyID: {
const StructType *STy = cast<StructType>(SubType);
const StructLayout &SL = *TD.getStructLayout(STy);
NextPadSize = SL.MemberOffsets[1];
else
NextPadSize = SubTypeSize;
- NextSubType = STy->getElementTypes()[0];
+ NextSubType = STy->getElementType(0);
NextSubTypeSize = TD.getTypeSize(NextSubType);
break;
}
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;
-// addEdgeTo - Add an edge from the current node to the specified node. This
-// can cause merging of nodes in the graph.
-//
+/// addEdgeTo - Add an edge from the current node to the specified node. This
+/// can cause merging of nodes in the graph.
+///
void DSNode::addEdgeTo(unsigned Offset, const DSNodeHandle &NH) {
- if (NH.getNode() == 0) return; // Nothing to do
+ if (NH.isNull()) return; // Nothing to do
DSNodeHandle &ExistingEdge = getLink(Offset);
- if (ExistingEdge.getNode()) {
+ if (!ExistingEdge.isNull()) {
// Merge the two nodes...
ExistingEdge.mergeWith(NH);
} else { // No merging to perform...
}
-// MergeSortedVectors - Efficiently merge a vector into another vector where
-// duplicates are not allowed and both are sorted. This assumes that 'T's are
-// efficiently copyable and have sane comparison semantics.
-//
+/// MergeSortedVectors - Efficiently merge a vector into another vector where
+/// duplicates are not allowed and both are sorted. This assumes that 'T's are
+/// efficiently copyable and have sane comparison semantics.
+///
static void MergeSortedVectors(std::vector<GlobalValue*> &Dest,
const std::vector<GlobalValue*> &Src) {
// By far, the most common cases will be the simple ones. In these cases,
}
}
+void DSNode::mergeGlobals(const std::vector<GlobalValue*> &RHS) {
+ MergeSortedVectors(Globals, RHS);
+}
-// MergeNodes() - Helper function for DSNode::mergeWith().
+// MergeNodes - Helper function for DSNode::mergeWith().
// This function does the hard work of merging two nodes, CurNodeH
// and NH after filtering out trivial cases and making sure that
// CurNodeH.offset >= NH.offset.
void DSNode::MergeNodes(DSNodeHandle& CurNodeH, DSNodeHandle& NH) {
assert(CurNodeH.getOffset() >= NH.getOffset() &&
"This should have been enforced in the caller.");
+ assert(CurNodeH.getNode()->getParentGraph()==NH.getNode()->getParentGraph() &&
+ "Cannot merge two nodes that are not in the same graph!");
// Now we know that Offset >= NH.Offset, so convert it so our "Offset" (with
// respect to NH.Offset) is now zero. NOffset is the distance from the base
if (CurNodeH.getNode() == N || N == 0) return;
assert(!CurNodeH.getNode()->isDeadNode());
- // Merge the NodeType information...
+ // Merge the NodeType information.
CurNodeH.getNode()->NodeType |= N->NodeType;
// Start forwarding to the new node!
// Merge the globals list...
if (!N->Globals.empty()) {
- MergeSortedVectors(CurNodeH.getNode()->Globals, N->Globals);
+ CurNodeH.getNode()->mergeGlobals(N->Globals);
// Delete the globals from the old node...
std::vector<GlobalValue*>().swap(N->Globals);
}
-// mergeWith - Merge this node and the specified node, moving all links to and
-// from the argument node into the current node, deleting the node argument.
-// Offset indicates what offset the specified node is to be merged into the
-// current node.
-//
-// The specified node may be a null pointer (in which case, nothing happens).
-//
+/// mergeWith - Merge this node and the specified node, moving all links to and
+/// from the argument node into the current node, deleting the node argument.
+/// Offset indicates what offset the specified node is to be merged into the
+/// current node.
+///
+/// The specified node may be a null pointer (in which case, we update it to
+/// point to this node).
+///
void DSNode::mergeWith(const DSNodeHandle &NH, unsigned Offset) {
DSNode *N = NH.getNode();
- if (N == 0 || (N == this && NH.getOffset() == Offset))
+ if (N == this && NH.getOffset() == Offset)
return; // Noop
+ // If the RHS is a null node, make it point to this node!
+ if (N == 0) {
+ NH.mergeWith(DSNodeHandle(this, Offset));
+ return;
+ }
+
assert(!N->isDeadNode() && !isDeadNode());
assert(!hasNoReferrers() && "Should not try to fold a useless node!");
DSNode::MergeNodes(CurNodeH, NHCopy);
}
+
+//===----------------------------------------------------------------------===//
+// ReachabilityCloner Implementation
+//===----------------------------------------------------------------------===//
+
+DSNodeHandle ReachabilityCloner::getClonedNH(const DSNodeHandle &SrcNH) {
+ if (SrcNH.isNull()) return DSNodeHandle();
+ const DSNode *SN = SrcNH.getNode();
+
+ DSNodeHandle &NH = NodeMap[SN];
+ if (!NH.isNull()) // Node already mapped?
+ return DSNodeHandle(NH.getNode(), NH.getOffset()+SrcNH.getOffset());
+
+ // If SrcNH has globals and the destination graph has one of the same globals,
+ // merge this node with the destination node, which is much more efficient.
+ if (SN->global_begin() != SN->global_end()) {
+ DSScalarMap &DestSM = Dest.getScalarMap();
+ for (DSNode::global_iterator I = SN->global_begin(), E = SN->global_end();
+ I != E; ++I) {
+ GlobalValue *GV = *I;
+ DSScalarMap::iterator GI = DestSM.find(GV);
+ if (GI != DestSM.end() && !GI->second.isNull()) {
+ // We found one, use merge instead!
+ merge(GI->second, Src.getNodeForValue(GV));
+ assert(!NH.isNull() && "Didn't merge node!");
+ return DSNodeHandle(NH.getNode(), NH.getOffset()+SrcNH.getOffset());
+ }
+ }
+ }
+
+ DSNode *DN = new DSNode(*SN, &Dest, true /* Null out all links */);
+ DN->maskNodeTypes(BitsToKeep);
+ NH = DN;
+
+ // Next, recursively clone all outgoing links as necessary. Note that
+ // adding these links can cause the node to collapse itself at any time, and
+ // the current node may be merged with arbitrary other nodes. For this
+ // reason, we must always go through NH.
+ DN = 0;
+ for (unsigned i = 0, e = SN->getNumLinks(); i != e; ++i) {
+ const DSNodeHandle &SrcEdge = SN->getLink(i << DS::PointerShift);
+ if (!SrcEdge.isNull()) {
+ const DSNodeHandle &DestEdge = getClonedNH(SrcEdge);
+ // Compute the offset into the current node at which to
+ // merge this link. In the common case, this is a linear
+ // relation to the offset in the original node (with
+ // wrapping), but if the current node gets collapsed due to
+ // recursive merging, we must make sure to merge in all remaining
+ // links at offset zero.
+ unsigned MergeOffset = 0;
+ DSNode *CN = NH.getNode();
+ if (CN->getSize() != 1)
+ MergeOffset = ((i << DS::PointerShift)+NH.getOffset()) % CN->getSize();
+ CN->addEdgeTo(MergeOffset, DestEdge);
+ }
+ }
+
+ // If this node contains any globals, make sure they end up in the scalar
+ // map with the correct offset.
+ for (DSNode::global_iterator I = SN->global_begin(), E = SN->global_end();
+ I != E; ++I) {
+ GlobalValue *GV = *I;
+ const DSNodeHandle &SrcGNH = Src.getNodeForValue(GV);
+ DSNodeHandle &DestGNH = NodeMap[SrcGNH.getNode()];
+ assert(DestGNH.getNode() == NH.getNode() &&"Global mapping inconsistent");
+ Dest.getNodeForValue(GV).mergeWith(DSNodeHandle(DestGNH.getNode(),
+ DestGNH.getOffset()+SrcGNH.getOffset()));
+
+ if (CloneFlags & DSGraph::UpdateInlinedGlobals)
+ Dest.getInlinedGlobals().insert(GV);
+ }
+ NH.getNode()->mergeGlobals(SN->getGlobals());
+
+ return DSNodeHandle(NH.getNode(), NH.getOffset()+SrcNH.getOffset());
+}
+
+void ReachabilityCloner::merge(const DSNodeHandle &NH,
+ const DSNodeHandle &SrcNH) {
+ if (SrcNH.isNull()) return; // Noop
+ if (NH.isNull()) {
+ // If there is no destination node, just clone the source and assign the
+ // destination node to be it.
+ NH.mergeWith(getClonedNH(SrcNH));
+ return;
+ }
+
+ // Okay, at this point, we know that we have both a destination and a source
+ // node that need to be merged. Check to see if the source node has already
+ // been cloned.
+ const DSNode *SN = SrcNH.getNode();
+ DSNodeHandle &SCNH = NodeMap[SN]; // SourceClonedNodeHandle
+ if (!SCNH.isNull()) { // Node already cloned?
+ NH.mergeWith(DSNodeHandle(SCNH.getNode(),
+ SCNH.getOffset()+SrcNH.getOffset()));
+
+ return; // Nothing to do!
+ }
+
+ // Okay, so the source node has not already been cloned. Instead of creating
+ // a new DSNode, only to merge it into the one we already have, try to perform
+ // the merge in-place. The only case we cannot handle here is when the offset
+ // into the existing node is less than the offset into the virtual node we are
+ // merging in. In this case, we have to extend the existing node, which
+ // requires an allocation anyway.
+ DSNode *DN = NH.getNode(); // Make sure the Offset is up-to-date
+ if (NH.getOffset() >= SrcNH.getOffset()) {
+ if (!DN->isNodeCompletelyFolded()) {
+ // Make sure the destination node is folded if the source node is folded.
+ if (SN->isNodeCompletelyFolded()) {
+ DN->foldNodeCompletely();
+ DN = NH.getNode();
+ } else if (SN->getSize() != DN->getSize()) {
+ // If the two nodes are of different size, and the smaller node has the
+ // array bit set, collapse!
+ if (SN->getSize() < DN->getSize()) {
+ if (SN->isArray()) {
+ DN->foldNodeCompletely();
+ DN = NH.getNode();
+ }
+ } else if (DN->isArray()) {
+ DN->foldNodeCompletely();
+ DN = NH.getNode();
+ }
+ }
+
+ // Merge the type entries of the two nodes together...
+ if (SN->getType() != Type::VoidTy && !DN->isNodeCompletelyFolded()) {
+ DN->mergeTypeInfo(SN->getType(), NH.getOffset()-SrcNH.getOffset());
+ DN = NH.getNode();
+ }
+ }
+
+ assert(!DN->isDeadNode());
+
+ // Merge the NodeType information.
+ DN->mergeNodeFlags(SN->getNodeFlags() & BitsToKeep);
+
+ // Before we start merging outgoing links and updating the scalar map, make
+ // sure it is known that this is the representative node for the src node.
+ SCNH = DSNodeHandle(DN, NH.getOffset()-SrcNH.getOffset());
+
+ // If the source node contains any globals, make sure they end up in the
+ // scalar map with the correct offset.
+ if (SN->global_begin() != SN->global_end()) {
+ // Update the globals in the destination node itself.
+ DN->mergeGlobals(SN->getGlobals());
+
+ // Update the scalar map for the graph we are merging the source node
+ // into.
+ for (DSNode::global_iterator I = SN->global_begin(), E = SN->global_end();
+ I != E; ++I) {
+ GlobalValue *GV = *I;
+ const DSNodeHandle &SrcGNH = Src.getNodeForValue(GV);
+ DSNodeHandle &DestGNH = NodeMap[SrcGNH.getNode()];
+ assert(DestGNH.getNode()==NH.getNode() &&"Global mapping inconsistent");
+ Dest.getNodeForValue(GV).mergeWith(DSNodeHandle(DestGNH.getNode(),
+ DestGNH.getOffset()+SrcGNH.getOffset()));
+
+ if (CloneFlags & DSGraph::UpdateInlinedGlobals)
+ Dest.getInlinedGlobals().insert(GV);
+ }
+ NH.getNode()->mergeGlobals(SN->getGlobals());
+ }
+ } else {
+ // We cannot handle this case without allocating a temporary node. Fall
+ // back on being simple.
+ DSNode *NewDN = new DSNode(*SN, &Dest, true /* Null out all links */);
+ NewDN->maskNodeTypes(BitsToKeep);
+
+ unsigned NHOffset = NH.getOffset();
+ NH.mergeWith(DSNodeHandle(NewDN, SrcNH.getOffset()));
+
+ assert(NH.getNode() &&
+ (NH.getOffset() > NHOffset ||
+ (NH.getOffset() == 0 && NH.getNode()->isNodeCompletelyFolded())) &&
+ "Merging did not adjust the offset!");
+
+ // Before we start merging outgoing links and updating the scalar map, make
+ // sure it is known that this is the representative node for the src node.
+ SCNH = DSNodeHandle(NH.getNode(), NH.getOffset()-SrcNH.getOffset());
+
+ // If the source node contained any globals, make sure to create entries
+ // in the scalar map for them!
+ for (DSNode::global_iterator I = SN->global_begin(), E = SN->global_end();
+ I != E; ++I) {
+ GlobalValue *GV = *I;
+ const DSNodeHandle &SrcGNH = Src.getNodeForValue(GV);
+ DSNodeHandle &DestGNH = NodeMap[SrcGNH.getNode()];
+ assert(DestGNH.getNode()==NH.getNode() &&"Global mapping inconsistent");
+ assert(SrcGNH.getNode() == SN && "Global mapping inconsistent");
+ Dest.getNodeForValue(GV).mergeWith(DSNodeHandle(DestGNH.getNode(),
+ DestGNH.getOffset()+SrcGNH.getOffset()));
+
+ if (CloneFlags & DSGraph::UpdateInlinedGlobals)
+ Dest.getInlinedGlobals().insert(GV);
+ }
+ }
+
+
+ // Next, recursively merge all outgoing links as necessary. Note that
+ // adding these links can cause the destination node to collapse itself at
+ // any time, and the current node may be merged with arbitrary other nodes.
+ // For this reason, we must always go through NH.
+ DN = 0;
+ for (unsigned i = 0, e = SN->getNumLinks(); i != e; ++i) {
+ const DSNodeHandle &SrcEdge = SN->getLink(i << DS::PointerShift);
+ if (!SrcEdge.isNull()) {
+ // Compute the offset into the current node at which to
+ // merge this link. In the common case, this is a linear
+ // relation to the offset in the original node (with
+ // wrapping), but if the current node gets collapsed due to
+ // recursive merging, we must make sure to merge in all remaining
+ // links at offset zero.
+ DSNode *CN = SCNH.getNode();
+ unsigned MergeOffset =
+ ((i << DS::PointerShift)+SCNH.getOffset()) % CN->getSize();
+
+ DSNodeHandle Tmp = CN->getLink(MergeOffset);
+ if (!Tmp.isNull()) {
+ // Perform the recursive merging. Make sure to create a temporary NH,
+ // because the Link can disappear in the process of recursive merging.
+ merge(Tmp, SrcEdge);
+ } else {
+ Tmp.mergeWith(getClonedNH(SrcEdge));
+ // Merging this could cause all kinds of recursive things to happen,
+ // culminating in the current node being eliminated. Since this is
+ // possible, make sure to reaquire the link from 'CN'.
+
+ unsigned MergeOffset = 0;
+ CN = SCNH.getNode();
+ MergeOffset = ((i << DS::PointerShift)+SCNH.getOffset()) %CN->getSize();
+ CN->getLink(MergeOffset).mergeWith(Tmp);
+ }
+ }
+ }
+}
+
+/// mergeCallSite - Merge the nodes reachable from the specified src call
+/// site into the nodes reachable from DestCS.
+void ReachabilityCloner::mergeCallSite(const DSCallSite &DestCS,
+ const DSCallSite &SrcCS) {
+ merge(DestCS.getRetVal(), SrcCS.getRetVal());
+ unsigned MinArgs = DestCS.getNumPtrArgs();
+ if (SrcCS.getNumPtrArgs() < MinArgs) MinArgs = SrcCS.getNumPtrArgs();
+
+ for (unsigned a = 0; a != MinArgs; ++a)
+ merge(DestCS.getPtrArg(a), SrcCS.getPtrArg(a));
+}
+
+
//===----------------------------------------------------------------------===//
// DSCallSite Implementation
//===----------------------------------------------------------------------===//
// 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();
}
+void DSCallSite::InitNH(DSNodeHandle &NH, const DSNodeHandle &Src,
+ ReachabilityCloner &RC) {
+ NH = RC.getClonedNH(Src);
+}
//===----------------------------------------------------------------------===//
// DSGraph Implementation
//===----------------------------------------------------------------------===//
-DSGraph::DSGraph(const DSGraph &G) : GlobalsGraph(0) {
+/// getFunctionNames - Return a space separated list of the name of the
+/// functions in this graph (if any)
+std::string DSGraph::getFunctionNames() const {
+ switch (getReturnNodes().size()) {
+ case 0: return "Globals graph";
+ case 1: return getReturnNodes().begin()->first->getName();
+ default:
+ std::string Return;
+ for (DSGraph::ReturnNodesTy::const_iterator I = getReturnNodes().begin();
+ I != getReturnNodes().end(); ++I)
+ Return += I->first->getName() + " ";
+ Return.erase(Return.end()-1, Return.end()); // Remove last space character
+ return Return;
+ }
+}
+
+
+DSGraph::DSGraph(const DSGraph &G) : GlobalsGraph(0), TD(G.TD) {
PrintAuxCalls = false;
NodeMapTy NodeMap;
cloneInto(G, ScalarMap, ReturnNodes, NodeMap);
}
DSGraph::DSGraph(const DSGraph &G, NodeMapTy &NodeMap)
- : GlobalsGraph(0) {
+ : GlobalsGraph(0), TD(G.TD) {
PrintAuxCalls = false;
cloneInto(G, ScalarMap, ReturnNodes, NodeMap);
}
DSGraph::~DSGraph() {
FunctionCalls.clear();
AuxFunctionCalls.clear();
+ InlinedGlobals.clear();
ScalarMap.clear();
ReturnNodes.clear();
// Drop all intra-node references, so that assertions don't fail...
- std::for_each(Nodes.begin(), Nodes.end(),
- std::mem_fun(&DSNode::dropAllReferences));
+ for (node_iterator NI = node_begin(), E = node_end(); NI != E; ++NI)
+ (*NI)->dropAllReferences();
- // Delete all of the nodes themselves...
- std::for_each(Nodes.begin(), Nodes.end(), deleter<DSNode>);
+ // Free all of the nodes.
+ Nodes.clear();
}
// dump - Allow inspection of graph in a debugger.
/// specified mapping.
///
void DSNode::remapLinks(DSGraph::NodeMapTy &OldNodeMap) {
- for (unsigned i = 0, e = Links.size(); i != e; ++i) {
- DSNodeHandle &H = OldNodeMap[Links[i].getNode()];
- Links[i].setNode(H.getNode());
- Links[i].setOffset(Links[i].getOffset()+H.getOffset());
- }
+ for (unsigned i = 0, e = Links.size(); i != e; ++i)
+ if (DSNode *N = Links[i].getNode()) {
+ DSGraph::NodeMapTy::const_iterator ONMI = OldNodeMap.find(N);
+ if (ONMI != OldNodeMap.end())
+ Links[i].setTo(ONMI->second.getNode(),
+ Links[i].getOffset()+ONMI->second.getOffset());
+ }
}
+/// updateFromGlobalGraph - This function rematerializes global nodes and
+/// nodes reachable from them from the globals graph into the current graph.
+/// It 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() {
+ TIME_REGION(X, "updateFromGlobalGraph");
+ ReachabilityCloner RC(*this, *GlobalsGraph, 0);
+
+ // Clone the non-up-to-date global nodes into this graph.
+ for (DSScalarMap::global_iterator I = getScalarMap().global_begin(),
+ E = getScalarMap().global_end(); I != E; ++I)
+ if (InlinedGlobals.count(*I) == 0) { // GNode is not up-to-date
+ DSScalarMap::iterator It = GlobalsGraph->ScalarMap.find(*I);
+ if (It != GlobalsGraph->ScalarMap.end())
+ RC.merge(getNodeForValue(*I), It->second);
+ }
+}
/// cloneInto - Clone the specified DSGraph into the current graph. The
/// translated ScalarMap for the old function is filled into the OldValMap
///
/// The CloneFlags member controls various aspects of the cloning process.
///
-void DSGraph::cloneInto(const DSGraph &G, ScalarMapTy &OldValMap,
+void DSGraph::cloneInto(const DSGraph &G, DSScalarMap &OldValMap,
ReturnNodesTy &OldReturnNodes, NodeMapTy &OldNodeMap,
unsigned CloneFlags) {
+ TIME_REGION(X, "cloneInto");
assert(OldNodeMap.empty() && "Returned OldNodeMap should be empty!");
assert(&G != this && "Cannot clone graph into itself!");
- unsigned FN = Nodes.size(); // First new node...
-
- // Duplicate all of the nodes, populating the node map...
- 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];
- DSNode *New = new DSNode(*Old, this);
+
+ for (node_iterator I = G.node_begin(), E = G.node_end(); I != E; ++I) {
+ assert(!(*I)->isForwarding() &&
+ "Forward nodes shouldn't be in node list!");
+ DSNode *New = new DSNode(**I, this);
New->maskNodeTypes(~BitsToClear);
- OldNodeMap[Old] = New;
+ OldNodeMap[*I] = New;
}
-
+
#ifndef NDEBUG
Timer::addPeakMemoryMeasurement();
#endif
-
+
// Rewrite the links in the new nodes to point into the current graph now.
- for (unsigned i = FN, e = Nodes.size(); i != e; ++i)
- Nodes[i]->remapLinks(OldNodeMap);
+ // Note that we don't loop over the node's list to do this. The problem is
+ // that remaping links can cause recursive merging to happen, which means
+ // that node_iterator's can get easily invalidated! Because of this, we
+ // loop over the OldNodeMap, which contains all of the new nodes as the
+ // .second element of the map elements. Also note that if we remap a node
+ // more than once, we won't break anything.
+ for (NodeMapTy::iterator I = OldNodeMap.begin(), E = OldNodeMap.end();
+ I != E; ++I)
+ I->second.getNode()->remapLinks(OldNodeMap);
// Copy the scalar map... merging all of the global nodes...
- for (ScalarMapTy::const_iterator I = G.ScalarMap.begin(),
+ for (DSScalarMap::const_iterator I = G.ScalarMap.begin(),
E = G.ScalarMap.end(); I != E; ++I) {
- DSNodeHandle &H = OldValMap[I->first];
DSNodeHandle &MappedNode = OldNodeMap[I->second.getNode()];
- H.setOffset(I->second.getOffset()+MappedNode.getOffset());
- H.setNode(MappedNode.getNode());
-
- if (isa<GlobalValue>(I->first)) { // Is this a global?
- ScalarMapTy::iterator GVI = ScalarMap.find(I->first);
- if (GVI != ScalarMap.end()) // Is the global value in this fn already?
- GVI->second.mergeWith(H);
- else
- ScalarMap[I->first] = H; // Add global pointer to this graph
+ DSNodeHandle &H = OldValMap[I->first];
+ H.mergeWith(DSNodeHandle(MappedNode.getNode(),
+ I->second.getOffset()+MappedNode.getOffset()));
+
+ // If this is a global, add the global to this fn or merge if already exists
+ if (GlobalValue* GV = dyn_cast<GlobalValue>(I->first)) {
+ ScalarMap[GV].mergeWith(H);
+ if (CloneFlags & DSGraph::UpdateInlinedGlobals)
+ InlinedGlobals.insert(GV);
}
}
}
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)
}
}
+static bool PathExistsToClonedNode(const DSNode *N, ReachabilityCloner &RC) {
+ if (N)
+ for (df_iterator<const DSNode*> I = df_begin(N), E = df_end(N); I != E; ++I)
+ if (RC.hasClonedNode(*I))
+ return true;
+ return false;
+}
+
+static bool PathExistsToClonedNode(const DSCallSite &CS,
+ ReachabilityCloner &RC) {
+ if (PathExistsToClonedNode(CS.getRetVal().getNode(), RC))
+ return true;
+ for (unsigned i = 0, e = CS.getNumPtrArgs(); i != e; ++i)
+ if (PathExistsToClonedNode(CS.getPtrArg(i).getNode(), RC))
+ return true;
+ return false;
+}
+
/// mergeInGraph - The method is used for merging graphs together. If the
/// argument graph is not *this, it makes a clone of the specified graph, then
/// merges the nodes specified in the call site with the formal arguments in the
/// graph.
///
-void DSGraph::mergeInGraph(DSCallSite &CS, Function &F, const DSGraph &Graph,
- unsigned CloneFlags) {
- ScalarMapTy OldValMap;
- ScalarMapTy *ScalarMap = &OldValMap;
- DSNodeHandle RetVal;
+void DSGraph::mergeInGraph(const DSCallSite &CS, Function &F,
+ const DSGraph &Graph, unsigned CloneFlags) {
+ TIME_REGION(X, "mergeInGraph");
+
+ // Fastpath for a noop inline.
+ if (CS.getNumPtrArgs() == 0 && CS.getRetVal().isNull())
+ return;
// If this is not a recursive call, clone the graph into this graph...
if (&Graph != this) {
- // Clone the callee's graph into the current graph, keeping
- // track of where scalars in the old graph _used_ to point,
- // and of the new nodes matching nodes of the old graph.
- NodeMapTy OldNodeMap;
+ // Clone the callee's graph into the current graph, keeping track of where
+ // scalars in the old graph _used_ to point, and of the new nodes matching
+ // nodes of the old graph.
+ ReachabilityCloner RC(*this, Graph, CloneFlags);
- // The clone call may invalidate any of the vectors in the data
- // structure graph. Strip locals and don't copy the list of callers
- ReturnNodesTy OldRetNodes;
- cloneInto(Graph, OldValMap, OldRetNodes, OldNodeMap, CloneFlags);
- RetVal = OldRetNodes[&F];
- ScalarMap = &OldValMap;
- } else {
- RetVal = getReturnNodeFor(F);
- ScalarMap = &getScalarMap();
- }
+ // Set up argument bindings
+ Function::aiterator AI = F.abegin();
+ for (unsigned i = 0, e = CS.getNumPtrArgs(); i != e; ++i, ++AI) {
+ // Advance the argument iterator to the first pointer argument...
+ while (AI != F.aend() && !isPointerType(AI->getType())) {
+ ++AI;
+#ifndef NDEBUG // FIXME: We should merge vararg arguments!
+ if (AI == F.aend() && !F.getFunctionType()->isVarArg())
+ std::cerr << "Bad call to Function: " << F.getName() << "\n";
+#endif
+ }
+ if (AI == F.aend()) break;
+
+ // Add the link from the argument scalar to the provided value.
+ RC.merge(CS.getPtrArg(i), Graph.getNodeForValue(AI));
+ }
+
+ // Map the return node pointer over.
+ if (!CS.getRetVal().isNull())
+ RC.merge(CS.getRetVal(), Graph.getReturnNodeFor(F));
+
+ // If requested, copy all of the calls.
+ if (!(CloneFlags & DontCloneCallNodes)) {
+ // Copy the function calls list...
+ FunctionCalls.reserve(FunctionCalls.size()+Graph.FunctionCalls.size());
+ for (unsigned i = 0, ei = Graph.FunctionCalls.size(); i != ei; ++i)
+ FunctionCalls.push_back(DSCallSite(Graph.FunctionCalls[i], RC));
+ }
- // Merge the return value with the return value of the context...
- RetVal.mergeWith(CS.getRetVal());
+ // If the user has us copying aux calls (the normal case), set up a data
+ // structure to keep track of which ones we've copied over.
+ std::vector<bool> CopiedAuxCall;
+ if (!(CloneFlags & DontCloneAuxCallNodes)) {
+ AuxFunctionCalls.reserve(AuxFunctionCalls.size()+
+ Graph.AuxFunctionCalls.size());
+ CopiedAuxCall.resize(Graph.AuxFunctionCalls.size());
+ }
+
+ // Clone over all globals that appear in the caller and callee graphs.
+ hash_set<GlobalVariable*> NonCopiedGlobals;
+ for (DSScalarMap::global_iterator GI = Graph.getScalarMap().global_begin(),
+ E = Graph.getScalarMap().global_end(); GI != E; ++GI)
+ if (GlobalVariable *GV = dyn_cast<GlobalVariable>(*GI))
+ if (ScalarMap.count(GV))
+ RC.merge(ScalarMap[GV], Graph.getNodeForValue(GV));
+ else
+ NonCopiedGlobals.insert(GV);
+
+ // If the global does not appear in the callers graph we generally don't
+ // want to copy the node. However, if there is a path from the node global
+ // node to a node that we did copy in the graph, we *must* copy it to
+ // maintain the connection information. Every time we decide to include a
+ // new global, this might make other globals live, so we must iterate
+ // unfortunately.
+ bool MadeChange = true;
+ while (MadeChange) {
+ MadeChange = false;
+ for (hash_set<GlobalVariable*>::iterator I = NonCopiedGlobals.begin();
+ I != NonCopiedGlobals.end();) {
+ DSNode *GlobalNode = Graph.getNodeForValue(*I).getNode();
+ if (RC.hasClonedNode(GlobalNode)) {
+ // Already cloned it, remove from set.
+ NonCopiedGlobals.erase(I++);
+ MadeChange = true;
+ } else if (PathExistsToClonedNode(GlobalNode, RC)) {
+ RC.getClonedNH(Graph.getNodeForValue(*I));
+ NonCopiedGlobals.erase(I++);
+ MadeChange = true;
+ } else {
+ ++I;
+ }
+ }
+
+ // If requested, copy any aux calls that can reach copied nodes.
+ if (!(CloneFlags & DontCloneAuxCallNodes)) {
+ for (unsigned i = 0, ei = Graph.AuxFunctionCalls.size(); i != ei; ++i)
+ if (!CopiedAuxCall[i] &&
+ PathExistsToClonedNode(Graph.AuxFunctionCalls[i], RC)) {
+ AuxFunctionCalls.push_back(DSCallSite(Graph.AuxFunctionCalls[i],
+ RC));
+ CopiedAuxCall[i] = true;
+ MadeChange = true;
+ }
+ }
+ }
- // Resolve all of the function arguments...
- Function::aiterator AI = F.abegin();
+ } else {
+ DSNodeHandle RetVal = getReturnNodeFor(F);
- for (unsigned i = 0, e = CS.getNumPtrArgs(); i != e; ++i, ++AI) {
- // Advance the argument iterator to the first pointer argument...
- while (AI != F.aend() && !isPointerType(AI->getType())) {
- ++AI;
-#ifndef NDEBUG
- if (AI == F.aend())
- std::cerr << "Bad call to Function: " << F.getName() << "\n";
+ // Merge the return value with the return value of the context...
+ RetVal.mergeWith(CS.getRetVal());
+
+ // Resolve all of the function arguments...
+ Function::aiterator AI = F.abegin();
+
+ for (unsigned i = 0, e = CS.getNumPtrArgs(); i != e; ++i, ++AI) {
+ // Advance the argument iterator to the first pointer argument...
+ while (AI != F.aend() && !isPointerType(AI->getType())) {
+ ++AI;
+#ifndef NDEBUG // FIXME: We should merge varargs arguments!!
+ if (AI == F.aend() && !F.getFunctionType()->isVarArg())
+ std::cerr << "Bad call to Function: " << F.getName() << "\n";
#endif
+ }
+ if (AI == F.aend()) break;
+
+ // Add the link from the argument scalar to the provided value
+ DSNodeHandle &NH = getNodeForValue(AI);
+ assert(NH.getNode() && "Pointer argument without scalarmap entry?");
+ NH.mergeWith(CS.getPtrArg(i));
}
- if (AI == F.aend()) break;
-
- // Add the link from the argument scalar to the provided value
- assert(ScalarMap->count(AI) && "Argument not in scalar map?");
- DSNodeHandle &NH = (*ScalarMap)[AI];
- assert(NH.getNode() && "Pointer argument without scalarmap entry?");
- NH.mergeWith(CS.getPtrArg(i));
}
}
+/// 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(getNodeForValue(I));
+
+ return DSCallSite(CallSite(), getReturnNodeFor(F), &F, Args);
+}
+
+/// getDSCallSiteForCallSite - Given an LLVM CallSite object that is live in
+/// the context of this graph, return the DSCallSite for it.
+DSCallSite DSGraph::getDSCallSiteForCallSite(CallSite CS) const {
+ DSNodeHandle RetVal;
+ Instruction *I = CS.getInstruction();
+ if (isPointerType(I->getType()))
+ RetVal = getNodeForValue(I);
+
+ std::vector<DSNodeHandle> Args;
+ Args.reserve(CS.arg_end()-CS.arg_begin());
+
+ // Calculate the arguments vector...
+ for (CallSite::arg_iterator I = CS.arg_begin(), E = CS.arg_end(); I != E; ++I)
+ if (isPointerType((*I)->getType()))
+ Args.push_back(getNodeForValue(*I));
+
+ // Add a new function call entry...
+ if (Function *F = CS.getCalledFunction())
+ return DSCallSite(CS, RetVal, F, Args);
+ else
+ return DSCallSite(CS, RetVal,
+ getNodeForValue(CS.getCalledValue()).getNode(), 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);
Function &F = *FI->first;
if (F.getName() != "main")
for (Function::aiterator I = F.abegin(), E = F.aend(); I != E; ++I)
- if (isPointerType(I->getType()) &&
- ScalarMap.find(I) != ScalarMap.end())
- markIncompleteNode(ScalarMap[I].getNode());
+ if (isPointerType(I->getType()))
+ markIncompleteNode(getNodeForValue(I).getNode());
}
// Mark stuff passed into functions calls as being incomplete...
// Mark all global nodes as incomplete...
if ((Flags & DSGraph::IgnoreGlobals) == 0)
- for (unsigned i = 0, e = Nodes.size(); i != e; ++i)
- if (Nodes[i]->isGlobalNode() && Nodes[i]->getNumLinks())
- markIncompleteNode(Nodes[i]);
+ for (DSScalarMap::global_iterator I = ScalarMap.global_begin(),
+ E = ScalarMap.global_end(); I != E; ++I)
+ if (GlobalVariable *GV = dyn_cast<GlobalVariable>(*I))
+ if (!GV->isConstant() || !GV->hasInitializer())
+ markIncompleteNode(ScalarMap[GV].getNode());
}
static inline void killIfUselessEdge(DSNodeHandle &Edge) {
// No interesting info?
if ((N->getNodeFlags() & ~DSNode::Incomplete) == 0 &&
N->getType() == Type::VoidTy && !N->isNodeCompletelyFolded())
- Edge.setNode(0); // Kill the edge!
+ Edge.setTo(0, 0); // Kill the edge!
}
static inline bool nodeContainsExternalFunction(const DSNode *N) {
unsigned NumFns = Calls.size();
std::sort(Calls.begin(), Calls.end()); // Sort by callee as primary key!
+#if 1
// Scan the call list cleaning it up as necessary...
DSNode *LastCalleeNode = 0;
Function *LastCalleeFunc = 0;
// If the Callee is a useless edge, this must be an unreachable call site,
// eliminate it.
if (CS.isIndirectCall() && CS.getCalleeNode()->getNumReferrers() == 1 &&
- CS.getCalleeNode()->getNodeFlags() == 0) { // No useful info?
- std::cerr << "WARNING: Useless call site found??\n";
+ CS.getCalleeNode()->isComplete() &&
+ CS.getCalleeNode()->getGlobals().empty()) { // No useful info?
+#ifndef NDEBUG
+ std::cerr << "WARNING: Useless call site found.\n";
+#endif
CS.swap(Calls.back());
Calls.pop_back();
--i;
else
LastCalleeContainsExternalFunction = LastCalleeFunc->isExternal();
}
-
- if (LastCalleeContainsExternalFunction ||
+
+ // It is not clear why, but enabling this code makes DSA really
+ // sensitive to node forwarding. Basically, with this enabled, DSA
+ // performs different number of inlinings based on which nodes are
+ // forwarding or not. This is clearly a problem, so this code is
+ // disabled until this can be resolved.
+#if 1
+ if (LastCalleeContainsExternalFunction
+#if 0
+ ||
// This should be more than enough context sensitivity!
// FIXME: Evaluate how many times this is tripped!
- NumDuplicateCalls > 20) {
+ NumDuplicateCalls > 20
+#endif
+ ) {
DSCallSite &OCS = Calls[i-1];
OCS.mergeWith(CS);
else if (CS.getNumPtrArgs() > OCS.getNumPtrArgs())
OCS = CS;
}
+#endif
} else {
if (CS.isDirectCall()) {
LastCalleeFunc = CS.getCalleeFunc();
}
}
}
-
- Calls.erase(std::unique(Calls.begin(), Calls.end()),
- Calls.end());
+#endif
+ Calls.erase(std::unique(Calls.begin(), Calls.end()), Calls.end());
// Track the number of call nodes merged away...
NumCallNodesMerged += NumFns-Calls.size();
// we don't have to perform any non-trivial analysis here.
//
void DSGraph::removeTriviallyDeadNodes() {
- removeIdenticalCalls(FunctionCalls);
- removeIdenticalCalls(AuxFunctionCalls);
+ TIME_REGION(X, "removeTriviallyDeadNodes");
+
+#if 0
+ /// NOTE: This code is disabled. This slows down DSA on 177.mesa
+ /// substantially!
+
+ // 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.
+ { TIME_REGION(X, "removeTriviallyDeadNodes:node_iterate");
+ for (node_iterator NI = node_begin(), E = node_end(); NI != E; ++NI) {
+ DSNode *N = *NI;
+ for (unsigned l = 0, e = N->getNumLinks(); l != e; ++l)
+ N->getLink(l*N->getPointerSize()).getNode();
+ }
+ }
+
+ // NOTE: This code is disabled. Though it should, in theory, allow us to
+ // remove more nodes down below, the scan of the scalar map is incredibly
+ // expensive for certain programs (with large SCCs). In the future, if we can
+ // make the scalar map scan more efficient, then we can reenable this.
+ { TIME_REGION(X, "removeTriviallyDeadNodes:scalarmap");
+
+ // Likewise, forward any edges from the scalar nodes. While we are at it,
+ // clean house a bit.
+ for (DSScalarMap::iterator I = ScalarMap.begin(),E = ScalarMap.end();I != E;){
+ I->second.getNode();
+ ++I;
+ }
+ }
+#endif
+ bool isGlobalsGraph = !GlobalsGraph;
- for (unsigned i = 0; i != Nodes.size(); ++i) {
- DSNode *Node = Nodes[i];
- if (Node->isComplete() && !Node->isModified() && !Node->isRead()) {
+ for (NodeListTy::iterator NI = Nodes.begin(), E = Nodes.end(); NI != E; ) {
+ DSNode &Node = *NI;
+
+ // 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) {
+ ++NI;
+ 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
// context), and it has no incoming edges. If it is a global node it may
// have all of these properties and still have incoming edges, due to the
// scalar map, so we check those now.
//
- if (Node->getNumReferrers() == Node->getGlobals().size()) {
- const std::vector<GlobalValue*> &Globals = Node->getGlobals();
+ if (Node.getNumReferrers() == Node.getGlobals().size()) {
+ const std::vector<GlobalValue*> &Globals = Node.getGlobals();
// 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!");
+ DSNode *N = getNodeForValue(Globals[j]).getNode();
+ assert(N == &Node && "ScalarMap doesn't match globals list!");
}
// Make sure NumReferrers still agrees, if so, the node is truly dead.
- if (Node->getNumReferrers() == Globals.size()) {
+ if (Node.getNumReferrers() == Globals.size()) {
for (unsigned j = 0, e = Globals.size(); j != e; ++j)
ScalarMap.erase(Globals[j]);
- Node->makeNodeDead();
+ Node.makeNodeDead();
+ ++NumTrivialGlobalDNE;
}
}
}
- if (Node->getNodeFlags() == 0 && Node->hasNoReferrers()) {
+ if (Node.getNodeFlags() == 0 && Node.hasNoReferrers()) {
// This node is dead!
- delete Node; // Free memory...
- Nodes[i--] = Nodes.back();
- Nodes.pop_back(); // Remove from node list...
+ NI = Nodes.erase(NI); // Erase & remove from node list.
+ ++NumTrivialDNE;
+ } else {
+ ++NI;
}
}
+
+ removeIdenticalCalls(FunctionCalls);
+ removeIdenticalCalls(AuxFunctionCalls);
}
void DSNode::markReachableNodes(hash_set<DSNode*> &ReachableNodes) {
if (this == 0) return;
assert(getForwardNode() == 0 && "Cannot mark a forwarded node!");
- if (ReachableNodes.count(this)) return; // Already marked reachable
- ReachableNodes.insert(this); // Is reachable now
-
- for (unsigned i = 0, e = getSize(); i < e; i += DS::PointerSize)
- getLink(i).getNode()->markReachableNodes(ReachableNodes);
+ if (ReachableNodes.insert(this).second) // Is newly reachable?
+ for (unsigned i = 0, e = getSize(); i < e; i += DS::PointerSize)
+ getLink(i).getNode()->markReachableNodes(ReachableNodes);
}
void DSCallSite::markReachableNodes(hash_set<DSNode*> &Nodes) {
// 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(); if (GlobalsGraph) 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...
+ TIME_REGION(X, "removeDeadNodes");
+
+ // FIXME: Merge non-trivially identical call nodes...
// Alive - a set that holds all nodes found to be reachable/alive.
hash_set<DSNode*> Alive;
std::vector<std::pair<Value*, DSNode*> > GlobalNodes;
+ // Copy and merge all information about globals to the GlobalsGraph if this is
+ // not a final pass (where unreachable globals are removed).
+ //
+ // 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.
+ //
+ ReachabilityCloner GGCloner(*GlobalsGraph, *this, DSGraph::StripAllocaBit |
+ DSGraph::StripIncompleteBit);
+
// Mark all nodes reachable by (non-global) scalar nodes as alive...
- for (ScalarMapTy::iterator I = ScalarMap.begin(), E = ScalarMap.end(); I !=E;)
+ { TIME_REGION(Y, "removeDeadNodes:scalarscan");
+ for (DSScalarMap::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()));
+
+ // Make sure that all globals are cloned over as roots.
+ if (!(Flags & DSGraph::RemoveUnreachableGlobals)) {
+ DSGraph::ScalarMapTy::iterator SMI =
+ GlobalsGraph->getScalarMap().find(I->first);
+ if (SMI != GlobalsGraph->getScalarMap().end())
+ GGCloner.merge(SMI->second, I->second);
+ else
+ GGCloner.getClonedNH(I->second);
+ }
++I;
} else {
+ DSNode *N = I->second.getNode();
+#if 0
// Check to see if this is a worthless node generated for non-pointer
// values, such as integers. Consider an addition of long types: A+B.
// Assuming we can track all uses of the value in this context, and it is
// uninteresting for data structure analysis. If we run across one of
// 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);
+ else {
+#endif
+ N->markReachableNodes(Alive);
++I;
- }
+ //}
}
+ }
- // The return value is alive as well...
+ // The return values are alive as well.
for (ReturnNodesTy::iterator I = ReturnNodes.begin(), E = ReturnNodes.end();
I != E; ++I)
I->second.getNode()->markReachableNodes(Alive);
for (unsigned i = 0, e = FunctionCalls.size(); i != e; ++i)
FunctionCalls[i].markReachableNodes(Alive);
+
+ // 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)) {
- 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 GGCloner
+ for (unsigned i = CurIdx, e = AuxFunctionCalls.size(); i != e; ++i)
+ GlobalsGraph->AuxFunctionCalls.push_back(DSCallSite(AuxFunctionCalls[i],
+ GGCloner));
}
// 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 GGCloner so we can destroy it.
+ GGCloner.destroy();
+
+ // 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());
- for (unsigned i = 0; i != Nodes.size(); ++i)
- if (!Alive.count(Nodes[i])) {
- 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();
- }
- } 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);
+ for (NodeListTy::iterator NI = Nodes.begin(), E = Nodes.end(); NI != E;) {
+ DSNode *N = NI++;
+ assert(!N->isForwarding() && "Forwarded node in nodes list?");
+
+ if (!Alive.count(N)) {
+ Nodes.remove(N);
+ assert(!N->isForwarding() && "Cannot remove a forwarding node!");
+ DeadNodes.push_back(N);
+ N->dropAllReferences();
+ ++NumDNE;
}
+ }
- // 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)
+ if (!Alive.count(GlobalNodes[i].second))
ScalarMap.erase(GlobalNodes[i].first);
- }
+ else
+ assert((Flags & DSGraph::RemoveUnreachableGlobals) && "non-dead global");
- // 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];
DEBUG(AssertGraphOK(); GlobalsGraph->AssertGraphOK());
}
+void DSGraph::AssertCallSiteInGraph(const DSCallSite &CS) const {
+ if (CS.isIndirectCall()) {
+ AssertNodeInGraph(CS.getCalleeNode());
+#if 0
+ if (CS.getNumPtrArgs() && CS.getCalleeNode() == CS.getPtrArg(0).getNode() &&
+ CS.getCalleeNode() && CS.getCalleeNode()->getGlobals().empty())
+ std::cerr << "WARNING: WIERD CALL SITE FOUND!\n";
+#endif
+ }
+ AssertNodeInGraph(CS.getRetVal().getNode());
+ for (unsigned j = 0, e = CS.getNumPtrArgs(); j != e; ++j)
+ AssertNodeInGraph(CS.getPtrArg(j).getNode());
+}
+
+void DSGraph::AssertCallNodesInGraph() const {
+ for (unsigned i = 0, e = FunctionCalls.size(); i != e; ++i)
+ AssertCallSiteInGraph(FunctionCalls[i]);
+}
+void DSGraph::AssertAuxCallNodesInGraph() const {
+ for (unsigned i = 0, e = AuxFunctionCalls.size(); i != e; ++i)
+ AssertCallSiteInGraph(AuxFunctionCalls[i]);
+}
+
void DSGraph::AssertGraphOK() const {
- for (unsigned i = 0, e = Nodes.size(); i != e; ++i)
- Nodes[i]->assertOK();
- return; // FIXME: remove
+ for (node_iterator NI = node_begin(), E = node_end(); NI != E; ++NI)
+ (*NI)->assertOK();
+
for (ScalarMapTy::const_iterator I = ScalarMap.begin(),
E = ScalarMap.end(); I != E; ++I) {
assert(I->second.getNode() && "Null node in scalarmap!");
AssertCallNodesInGraph();
AssertAuxCallNodesInGraph();
}
+
+/// computeNodeMapping - Given roots in two different DSGraphs, traverse the
+/// nodes reachable from the two graphs, computing the mapping of nodes from
+/// the first to the second graph.
+///
+void DSGraph::computeNodeMapping(const DSNodeHandle &NH1,
+ const DSNodeHandle &NH2, NodeMapTy &NodeMap,
+ bool StrictChecking) {
+ DSNode *N1 = NH1.getNode(), *N2 = NH2.getNode();
+ if (N1 == 0 || N2 == 0) return;
+
+ DSNodeHandle &Entry = NodeMap[N1];
+ if (Entry.getNode()) {
+ // Termination of recursion!
+ if (StrictChecking) {
+ assert(Entry.getNode() == N2 && "Inconsistent mapping detected!");
+ assert((Entry.getOffset() == (NH2.getOffset()-NH1.getOffset()) ||
+ Entry.getNode()->isNodeCompletelyFolded()) &&
+ "Inconsistent mapping detected!");
+ }
+ return;
+ }
+
+ Entry.setTo(N2, NH2.getOffset()-NH1.getOffset());
+
+ // Loop over all of the fields that N1 and N2 have in common, recursively
+ // mapping the edges together now.
+ int N2Idx = NH2.getOffset()-NH1.getOffset();
+ unsigned N2Size = N2->getSize();
+ for (unsigned i = 0, e = N1->getSize(); i < e; i += DS::PointerSize)
+ if (unsigned(N2Idx)+i < N2Size)
+ computeNodeMapping(N1->getLink(i), N2->getLink(N2Idx+i), NodeMap);
+ else
+ computeNodeMapping(N1->getLink(i),
+ N2->getLink(unsigned(N2Idx+i) % N2Size), NodeMap);
+}
projects / oota-llvm.git / blobdiff