//===- 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"
#include <algorithm>
-#include <set>
-
-using std::vector;
+using namespace llvm;
namespace {
Statistic<> NumFolds ("dsnode", "Number of nodes completely folded");
Statistic<> NumCallNodesMerged("dsnode", "Number of call nodes merged");
};
-namespace DS { // TODO: FIXME
- extern TargetData TD;
-}
+#if 0
+#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!");
+
+ // Handle node forwarding here!
+ DSNode *Next = N->ForwardNH.getNode(); // Cause recursive shrinkage
+ Offset += N->ForwardNH.getOffset();
+
+ if (--N->NumReferrers == 0) {
+ // Removing the last referrer to the node, sever the forwarding link
+ N->stopForwarding();
+ }
+
+ N = Next;
+ N->NumReferrers++;
+ if (N->Size <= Offset) {
+ assert(N->Size <= 1 && "Forwarded to shrunk but not collapsed node?");
+ Offset = 0;
+ }
+ return N;
+}
+
//===----------------------------------------------------------------------===//
// DSNode Implementation
//===----------------------------------------------------------------------===//
-DSNode::DSNode(enum NodeTy NT, const Type *T)
- : Ty(Type::VoidTy), Size(0), NodeType(NT) {
+DSNode::DSNode(const Type *T, DSGraph *G)
+ : 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);
}
// DSNode copy constructor... do not copy over the referrers list!
-DSNode::DSNode(const DSNode &N)
- : Links(N.Links), Globals(N.Globals), Ty(N.Ty), Size(N.Size),
- NodeType(N.NodeType) {
+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);
}
-void DSNode::removeReferrer(DSNodeHandle *H) {
- // Search backwards, because we depopulate the list from the back for
- // efficiency (because it's a vector).
- vector<DSNodeHandle*>::reverse_iterator I =
- std::find(Referrers.rbegin(), Referrers.rend(), H);
- assert(I != Referrers.rend() && "Referrer not pointing to node!");
- Referrers.erase(I.base()-1);
+/// 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
+/// should be forwarded to the specified node and offset.
+///
+void DSNode::forwardNode(DSNode *To, unsigned Offset) {
+ assert(this != To && "Cannot forward a node to itself!");
+ assert(ForwardNH.isNull() && "Already forwarding from this node!");
+ 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);
+ NodeType = DEAD;
+ Size = 0;
+ Ty = Type::VoidTy;
}
// addGlobal - Add an entry for a global value to the Globals list. This also
//
void DSNode::addGlobal(GlobalValue *GV) {
// Keep the list sorted.
- vector<GlobalValue*>::iterator I =
+ std::vector<GlobalValue*>::iterator I =
std::lower_bound(Globals.begin(), Globals.end(), GV);
if (I == Globals.end() || *I != GV) {
/// single byte with a single TypeEntry of "void".
///
void DSNode::foldNodeCompletely() {
- if (isNodeCompletelyFolded()) return;
+ if (isNodeCompletelyFolded()) return; // If this node is already folded...
++NumFolds;
- // We are no longer typed at all...
- Ty = DSTypeRec(Type::VoidTy, true);
- Size = 1;
+ // 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);
- // Loop over all of our referrers, making them point to our zero bytes of
- // space.
- for (vector<DSNodeHandle*>::iterator I = Referrers.begin(), E=Referrers.end();
- I != E; ++I)
- (*I)->setOffset(0);
-
- // If we have links, merge all of our outgoing links together...
- for (unsigned i = 1, e = Links.size(); i < e; ++i)
- Links[0].mergeWith(Links[i]);
- Links.resize(1);
+ // 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();
+ } else {
+ DestNode->Links.resize(1);
+ }
}
/// isNodeCompletelyFolded - Return true if this node has been completely
/// all of the field sensitivity that may be present in the node.
///
bool DSNode::isNodeCompletelyFolded() const {
- return getSize() == 1 && Ty.Ty == Type::VoidTy && Ty.isArray;
+ return getSize() == 1 && Ty == Type::VoidTy && isArray();
+}
+
+namespace {
+ /// TypeElementWalker Class - Used for implementation of physical subtyping...
+ ///
+ class TypeElementWalker {
+ struct StackState {
+ const Type *Ty;
+ unsigned Offset;
+ unsigned Idx;
+ StackState(const Type *T, unsigned Off = 0)
+ : Ty(T), Offset(Off), Idx(0) {}
+ };
+
+ std::vector<StackState> Stack;
+ const TargetData &TD;
+ public:
+ TypeElementWalker(const Type *T, const TargetData &td) : TD(td) {
+ Stack.push_back(T);
+ StepToLeaf();
+ }
+
+ bool isDone() const { return Stack.empty(); }
+ const Type *getCurrentType() const { return Stack.back().Ty; }
+ unsigned getCurrentOffset() const { return Stack.back().Offset; }
+
+ void StepToNextType() {
+ PopStackAndAdvance();
+ StepToLeaf();
+ }
+
+ private:
+ /// PopStackAndAdvance - Pop the current element off of the stack and
+ /// advance the underlying element to the next contained member.
+ void PopStackAndAdvance() {
+ assert(!Stack.empty() && "Cannot pop an empty stack!");
+ Stack.pop_back();
+ while (!Stack.empty()) {
+ StackState &SS = Stack.back();
+ if (const StructType *ST = dyn_cast<StructType>(SS.Ty)) {
+ ++SS.Idx;
+ if (SS.Idx != ST->getElementTypes().size()) {
+ const StructLayout *SL = TD.getStructLayout(ST);
+ SS.Offset += SL->MemberOffsets[SS.Idx]-SL->MemberOffsets[SS.Idx-1];
+ return;
+ }
+ Stack.pop_back(); // At the end of the structure
+ } else {
+ const ArrayType *AT = cast<ArrayType>(SS.Ty);
+ ++SS.Idx;
+ if (SS.Idx != AT->getNumElements()) {
+ SS.Offset += TD.getTypeSize(AT->getElementType());
+ return;
+ }
+ Stack.pop_back(); // At the end of the array
+ }
+ }
+ }
+
+ /// StepToLeaf - Used by physical subtyping to move to the first leaf node
+ /// on the type stack.
+ void StepToLeaf() {
+ if (Stack.empty()) 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()) {
+ assert(SS.Idx == 0);
+ PopStackAndAdvance();
+ } else {
+ // Step into the structure...
+ assert(SS.Idx < ST->getElementTypes().size());
+ const StructLayout *SL = TD.getStructLayout(ST);
+ Stack.push_back(StackState(ST->getElementTypes()[SS.Idx],
+ SS.Offset+SL->MemberOffsets[SS.Idx]));
+ }
+ } else {
+ const ArrayType *AT = cast<ArrayType>(SS.Ty);
+ if (AT->getNumElements() == 0) {
+ assert(SS.Idx == 0);
+ PopStackAndAdvance();
+ } else {
+ // Step into the array...
+ assert(SS.Idx < AT->getNumElements());
+ Stack.push_back(StackState(AT->getElementType(),
+ SS.Offset+SS.Idx*
+ TD.getTypeSize(AT->getElementType())));
+ }
+ }
+ }
+ }
+ };
+} // 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. If AllowLargerT1
+/// is true, then we also allow a larger T1.
+///
+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())
+ return false;
+
+ const Type *T1 = T1W.getCurrentType();
+ const Type *T2 = T2W.getCurrentType();
+ if (T1 != T2 && !T1->isLosslesslyConvertibleTo(T2))
+ return false;
+
+ T1W.StepToNextType();
+ T2W.StepToNextType();
+ }
+
+ return AllowLargerT1 || T1W.isDone();
}
///
/// This method returns true if the node is completely folded, otherwise false.
///
-bool DSNode::mergeTypeInfo(const Type *NewTy, unsigned Offset) {
+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.
// Size = 1, Ty = Void, Array = 1: The node is collapsed
// Otherwise, sizeof(Ty) = Size
//
- assert(((Size == 0 && Ty.Ty == Type::VoidTy && !Ty.isArray) ||
- (Size == 0 && !Ty.Ty->isSized() && !Ty.isArray) ||
- (Size == 1 && Ty.Ty == Type::VoidTy && Ty.isArray) ||
- (Size == 0 && !Ty.Ty->isSized() && !Ty.isArray) ||
- (TD.getTypeSize(Ty.Ty) == Size)) &&
+ assert(((Size == 0 && Ty == Type::VoidTy && !isArray()) ||
+ (Size == 0 && !Ty->isSized() && !isArray()) ||
+ (Size == 1 && Ty == Type::VoidTy && isArray()) ||
+ (Size == 0 && !Ty->isSized() && !isArray()) ||
+ (TD.getTypeSize(Ty) == Size)) &&
"Size member of DSNode doesn't match the type structure!");
assert(NewTy != Type::VoidTy && "Cannot merge void type into DSNode!");
- if (Offset == 0 && NewTy == Ty.Ty)
+ if (Offset == 0 && NewTy == Ty)
return false; // This should be a common case, handle it efficiently
// Return true immediately if the node is completely folded.
if (isNodeCompletelyFolded()) return true;
+ // If this is an array type, eliminate the outside arrays because they won't
+ // be used anyway. This greatly reduces the size of large static arrays used
+ // as global variables, for example.
+ //
+ bool WillBeArray = false;
+ while (const ArrayType *AT = dyn_cast<ArrayType>(NewTy)) {
+ // FIXME: we might want to keep small arrays, but must be careful about
+ // things like: [2 x [10000 x int*]]
+ NewTy = AT->getElementType();
+ WillBeArray = true;
+ }
+
// Figure out how big the new type we're merging in is...
unsigned NewTySize = NewTy->isSized() ? TD.getTypeSize(NewTy) : 0;
// we can't, we fold the node completely, if we can, we potentially update our
// internal state.
//
- if (Ty.Ty == Type::VoidTy) {
+ 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(Ty.isArray == false && "This shouldn't happen!");
- Ty.Ty = NewTy;
+ assert(Offset == 0 && !isArray() &&
+ "Cannot have an offset into a void node!");
+ Ty = NewTy;
+ NodeType &= ~Array;
+ if (WillBeArray) NodeType |= Array;
Size = NewTySize;
// Calculate the number of outgoing links from this node.
if (Offset+NewTySize > Size) {
// It is illegal to grow this node if we have treated it as an array of
// objects...
- if (Ty.isArray) {
- foldNodeCompletely();
+ if (isArray()) {
+ if (FoldIfIncompatible) foldNodeCompletely();
return true;
}
if (Offset) { // We could handle this case, but we don't for now...
- DEBUG(std::cerr << "UNIMP: Trying to merge a growth type into "
- << "offset != 0: Collapsing!\n");
- foldNodeCompletely();
+ std::cerr << "UNIMP: Trying to merge a growth type into "
+ << "offset != 0: Collapsing!\n";
+ if (FoldIfIncompatible) foldNodeCompletely();
return true;
}
// hit the other code path here. If the other code path decides it's not
// ok, it will collapse the node as appropriate.
//
- const Type *OldTy = Ty.Ty;
- Ty.Ty = NewTy;
+ const Type *OldTy = Ty;
+ Ty = NewTy;
+ NodeType &= ~Array;
+ if (WillBeArray) NodeType |= Array;
Size = NewTySize;
// Must grow links to be the appropriate size...
assert(Offset <= Size &&
"Cannot merge something into a part of our type that doesn't exist!");
- // Find the section of Ty.Ty that NewTy overlaps with... first we find the
+ // Find the section of Ty that NewTy overlaps with... first we find the
// type that starts at offset Offset.
//
unsigned O = 0;
- const Type *SubType = Ty.Ty;
+ const Type *SubType = Ty;
while (O < Offset) {
assert(Offset-O < TD.getTypeSize(SubType) && "Offset out of range!");
break;
}
default:
- assert(0 && "Unknown type!");
+ if (FoldIfIncompatible) foldNodeCompletely();
+ return true;
}
}
// If we found our type exactly, early exit
if (SubType == 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, !isArray(), TD))
+ return false;
+
// Okay, so we found the leader type at the offset requested. Search the list
// of types that starts at this offset. If SubType is currently an array or
// structure, the type desired may actually be the first element of the
// composite type...
//
- unsigned SubTypeSize = SubType->isSized() ? TD.getTypeSize(SubType) : 0;
+ unsigned PadSize = SubTypeSize; // Size, including pad memory which is ignored
while (SubType != NewTy) {
const Type *NextSubType = 0;
- unsigned NextSubTypeSize;
+ unsigned NextSubTypeSize = 0;
+ unsigned NextPadSize = 0;
switch (SubType->getPrimitiveID()) {
- case Type::StructTyID:
- NextSubType = cast<StructType>(SubType)->getElementTypes()[0];
- NextSubTypeSize = TD.getTypeSize(SubType);
+ case Type::StructTyID: {
+ const StructType *STy = cast<StructType>(SubType);
+ const StructLayout &SL = *TD.getStructLayout(STy);
+ if (SL.MemberOffsets.size() > 1)
+ NextPadSize = SL.MemberOffsets[1];
+ else
+ NextPadSize = SubTypeSize;
+ NextSubType = STy->getElementTypes()[0];
+ NextSubTypeSize = TD.getTypeSize(NextSubType);
break;
+ }
case Type::ArrayTyID:
NextSubType = cast<ArrayType>(SubType)->getElementType();
- NextSubTypeSize = TD.getTypeSize(SubType);
+ NextSubTypeSize = TD.getTypeSize(NextSubType);
+ NextPadSize = NextSubTypeSize;
break;
default: ;
// fall out
if (NextSubType == 0)
break; // In the default case, break out of the loop
- if (NextSubTypeSize < NewTySize)
+ if (NextPadSize < NewTySize)
break; // Don't allow shrinking to a smaller type than NewTySize
SubType = NextSubType;
SubTypeSize = NextSubTypeSize;
+ PadSize = NextPadSize;
}
// If we found the type exactly, return it...
// Check to see if we have a compatible, but different type...
if (NewTySize == SubTypeSize) {
- // Check to see if this type is obviously convertable... int -> uint f.e.
- if (NewTy->isLosslesslyConvertableTo(SubType))
+ // Check to see if this type is obviously convertible... int -> uint f.e.
+ if (NewTy->isLosslesslyConvertibleTo(SubType))
return false;
// Check to see if we have a pointer & integer mismatch going on here,
if (SubType->isInteger() && isa<PointerType>(NewTy) ||
NewTy->isInteger() && isa<PointerType>(SubType))
return false;
-
+ } else if (NewTySize > SubTypeSize && NewTySize <= PadSize) {
+ // We are accessing the field, plus some structure padding. Ignore the
+ // structure padding.
+ return false;
}
+ 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");
- DEBUG(std::cerr << "MergeTypeInfo Folding OrigTy: " << Ty.Ty
- << "\n due to:" << NewTy << " @ " << Offset << "!\n"
- << "SubType: " << SubType << "\n\n");
-
- foldNodeCompletely();
+ if (FoldIfIncompatible) foldNodeCompletely();
return true;
}
// duplicates are not allowed and both are sorted. This assumes that 'T's are
// efficiently copyable and have sane comparison semantics.
//
-template<typename T>
-void MergeSortedVectors(vector<T> &Dest, const vector<T> &Src) {
+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,
// avoid having to allocate a temporary vector...
//
} else if (Dest.empty()) { // Just copy the result in...
Dest = Src;
} else if (Src.size() == 1) { // Insert a single element...
- const T &V = Src[0];
- typename vector<T>::iterator I =
+ const GlobalValue *V = Src[0];
+ std::vector<GlobalValue*>::iterator I =
std::lower_bound(Dest.begin(), Dest.end(), V);
if (I == Dest.end() || *I != Src[0]) // If not already contained...
Dest.insert(I, Src[0]);
} else if (Dest.size() == 1) {
- T Tmp = Dest[0]; // Save value in temporary...
+ GlobalValue *Tmp = Dest[0]; // Save value in temporary...
Dest = Src; // Copy over list...
- typename vector<T>::iterator I =
- std::lower_bound(Dest.begin(), Dest.end(),Tmp);
- if (I == Dest.end() || *I != Src[0]) // If not already contained...
- Dest.insert(I, Src[0]);
+ std::vector<GlobalValue*>::iterator I =
+ std::lower_bound(Dest.begin(), Dest.end(), Tmp);
+ if (I == Dest.end() || *I != Tmp) // If not already contained...
+ Dest.insert(I, Tmp);
} else {
// Make a copy to the side of Dest...
- vector<T> Old(Dest);
+ std::vector<GlobalValue*> Old(Dest);
// Make space for all of the type entries now...
Dest.resize(Dest.size()+Src.size());
}
+// 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.
+//
+// ***WARNING***
+// Since merging may cause either node to go away, we must always
+// use the node-handles to refer to the nodes. These node handles are
+// automatically updated during merging, so will always provide access
+// to the correct node after a merge.
+//
+void DSNode::MergeNodes(DSNodeHandle& CurNodeH, DSNodeHandle& NH) {
+ assert(CurNodeH.getOffset() >= NH.getOffset() &&
+ "This should have been enforced in the caller.");
+
+ // 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
+ // of our object that N starts from.
+ //
+ unsigned NOffset = CurNodeH.getOffset()-NH.getOffset();
+ unsigned NSize = NH.getNode()->getSize();
+
+ // If the two nodes are of different size, and the smaller node has the array
+ // bit set, collapse!
+ if (NSize != CurNodeH.getNode()->getSize()) {
+ if (NSize < CurNodeH.getNode()->getSize()) {
+ if (NH.getNode()->isArray())
+ NH.getNode()->foldNodeCompletely();
+ } else if (CurNodeH.getNode()->isArray()) {
+ NH.getNode()->foldNodeCompletely();
+ }
+ }
+
+ // Merge the type entries of the two nodes together...
+ if (NH.getNode()->Ty != Type::VoidTy)
+ CurNodeH.getNode()->mergeTypeInfo(NH.getNode()->Ty, NOffset);
+ assert(!CurNodeH.getNode()->isDeadNode());
+
+ // If we are merging a node with a completely folded node, then both nodes are
+ // now completely folded.
+ //
+ if (CurNodeH.getNode()->isNodeCompletelyFolded()) {
+ if (!NH.getNode()->isNodeCompletelyFolded()) {
+ NH.getNode()->foldNodeCompletely();
+ assert(NH.getNode() && NH.getOffset() == 0 &&
+ "folding did not make offset 0?");
+ NOffset = NH.getOffset();
+ NSize = NH.getNode()->getSize();
+ assert(NOffset == 0 && NSize == 1);
+ }
+ } else if (NH.getNode()->isNodeCompletelyFolded()) {
+ CurNodeH.getNode()->foldNodeCompletely();
+ assert(CurNodeH.getNode() && CurNodeH.getOffset() == 0 &&
+ "folding did not make offset 0?");
+ NOffset = NH.getOffset();
+ NSize = NH.getNode()->getSize();
+ assert(NOffset == 0 && NSize == 1);
+ }
+
+ DSNode *N = NH.getNode();
+ if (CurNodeH.getNode() == N || N == 0) return;
+ assert(!CurNodeH.getNode()->isDeadNode());
+
+ // Merge the NodeType information...
+ CurNodeH.getNode()->NodeType |= N->NodeType;
+
+ // Start forwarding to the new node!
+ N->forwardNode(CurNodeH.getNode(), NOffset);
+ assert(!CurNodeH.getNode()->isDeadNode());
+
+ // Make all of the outgoing links of N now be outgoing links of CurNodeH.
+ //
+ for (unsigned i = 0; i < N->getNumLinks(); ++i) {
+ DSNodeHandle &Link = N->getLink(i << DS::PointerShift);
+ if (Link.getNode()) {
+ // 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 = CurNodeH.getNode();
+ if (CN->Size != 1)
+ MergeOffset = ((i << DS::PointerShift)+NOffset) % CN->getSize();
+ CN->addEdgeTo(MergeOffset, Link);
+ }
+ }
+
+ // Now that there are no outgoing edges, all of the Links are dead.
+ N->Links.clear();
+
+ // Merge the globals list...
+ if (!N->Globals.empty()) {
+ MergeSortedVectors(CurNodeH.getNode()->Globals, 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).
+// 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
- assert((N->NodeType & DSNode::DEAD) == 0);
- assert((NodeType & DSNode::DEAD) == 0);
+ // 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!");
if (N == this) {
return;
}
- // Merge the type entries of the two nodes together...
- if (N->Ty.Ty != Type::VoidTy) {
- mergeTypeInfo(N->Ty.Ty, Offset);
-
- // mergeTypeInfo can cause collapsing, which can cause this node to become
- // dead.
- if (hasNoReferrers()) return;
- }
- assert((NodeType & DSNode::DEAD) == 0);
-
- // If we are merging a node with a completely folded node, then both nodes are
- // now completely folded.
- //
- if (isNodeCompletelyFolded()) {
- if (!N->isNodeCompletelyFolded()) {
- N->foldNodeCompletely();
- if (hasNoReferrers()) return;
- }
- } else if (N->isNodeCompletelyFolded()) {
- foldNodeCompletely();
- Offset = 0;
- if (hasNoReferrers()) return;
- }
- N = NH.getNode();
- assert((NodeType & DSNode::DEAD) == 0);
-
- if (this == N || N == 0) return;
- assert((NodeType & DSNode::DEAD) == 0);
-
// If both nodes are not at offset 0, make sure that we are merging the node
// at an later offset into the node with the zero offset.
//
- if (Offset > NH.getOffset()) {
+ if (Offset < NH.getOffset()) {
N->mergeWith(DSNodeHandle(this, Offset), NH.getOffset());
return;
} else if (Offset == NH.getOffset() && getSize() < N->getSize()) {
return;
}
-#if 0
- std::cerr << "\n\nMerging:\n";
- N->print(std::cerr, 0);
- std::cerr << " and:\n";
- print(std::cerr, 0);
-#endif
-
- // Now we know that Offset <= NH.Offset, so convert it so our "Offset" (with
- // respect to NH.Offset) is now zero.
- //
- unsigned NOffset = NH.getOffset()-Offset;
- unsigned NSize = N->getSize();
-
- assert((NodeType & DSNode::DEAD) == 0);
-
- // Remove all edges pointing at N, causing them to point to 'this' instead.
- // Make sure to adjust their offset, not just the node pointer.
- //
- while (!N->Referrers.empty()) {
- DSNodeHandle &Ref = *N->Referrers.back();
- Ref = DSNodeHandle(this, NOffset+Ref.getOffset());
- }
- assert((NodeType & DSNode::DEAD) == 0);
-
- // Make all of the outgoing links of N now be outgoing links of this. This
- // can cause recursive merging!
- //
- for (unsigned i = 0; i < NSize; i += DS::PointerSize) {
- DSNodeHandle &Link = N->getLink(i);
- if (Link.getNode()) {
- addEdgeTo((i+NOffset) % getSize(), Link);
-
- // It's possible that after adding the new edge that some recursive
- // merging just occured, causing THIS node to get merged into oblivion.
- // If that happens, we must not try to merge any more edges into it!
- //
- if (Size == 0) return;
- }
- }
-
- // Now that there are no outgoing edges, all of the Links are dead.
- N->Links.clear();
- N->Size = 0;
- N->Ty.Ty = Type::VoidTy;
- N->Ty.isArray = false;
-
- // Merge the node types
- NodeType |= N->NodeType;
- N->NodeType = DEAD; // N is now a dead node.
-
- // Merge the globals list...
- if (!N->Globals.empty()) {
- MergeSortedVectors(Globals, N->Globals);
-
- // Delete the globals from the old node...
- N->Globals.clear();
- }
+ // Ok, now we can merge the two nodes. Use a static helper that works with
+ // two node handles, since "this" may get merged away at intermediate steps.
+ DSNodeHandle CurNodeH(this, Offset);
+ DSNodeHandle NHCopy(NH);
+ DSNode::MergeNodes(CurNodeH, NHCopy);
}
//===----------------------------------------------------------------------===//
// 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 Implementation
//===----------------------------------------------------------------------===//
-DSGraph::DSGraph(const DSGraph &G) : Func(G.Func) {
- std::map<const DSNode*, DSNodeHandle> NodeMap;
- RetNode = cloneInto(G, ScalarMap, NodeMap);
+/// 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);
+ InlinedGlobals.clear(); // clear set of "up-to-date" globals
}
-DSGraph::DSGraph(const DSGraph &G,
- std::map<const DSNode*, DSNodeHandle> &NodeMap)
- : Func(G.Func) {
- RetNode = cloneInto(G, ScalarMap, NodeMap);
+DSGraph::DSGraph(const DSGraph &G, NodeMapTy &NodeMap)
+ : 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();
- RetNode.setNode(0);
+ ReturnNodes.clear();
-#ifndef NDEBUG
// Drop all intra-node references, so that assertions don't fail...
std::for_each(Nodes.begin(), Nodes.end(),
std::mem_fun(&DSNode::dropAllReferences));
-#endif
// Delete all of the nodes themselves...
std::for_each(Nodes.begin(), Nodes.end(), deleter<DSNode>);
/// remapLinks - Change all of the Links in the current node according to the
/// specified mapping.
///
-void DSNode::remapLinks(std::map<const DSNode*, DSNodeHandle> &OldNodeMap) {
+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());
}
-// cloneInto - Clone the specified DSGraph into the current graph, returning the
-// Return node of the graph. The translated ScalarMap for the old function is
-// filled into the OldValMap member. If StripAllocas is set to true, Alloca
-// markers are removed from the graph, as the graph is being cloned into a
-// calling function's graph.
-//
-DSNodeHandle DSGraph::cloneInto(const DSGraph &G,
- std::map<Value*, DSNodeHandle> &OldValMap,
- std::map<const DSNode*, DSNodeHandle> &OldNodeMap,
- unsigned CloneFlags) {
+/// 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.
+///
+/// The CloneFlags member controls various aspects of the cloning process.
+///
+void DSGraph::cloneInto(const DSGraph &G, ScalarMapTy &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!");
// 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)
+ | ((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);
- New->NodeType &= ~DSNode::DEAD; // Clear dead flag...
- Nodes.push_back(New);
+ DSNode *New = new DSNode(*Old, this);
+ New->maskNodeTypes(~BitsToClear);
OldNodeMap[Old] = 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);
- // Remove alloca markers as specified
- if (CloneFlags & StripAllocaBit)
- for (unsigned i = FN, e = Nodes.size(); i != e; ++i)
- Nodes[i]->NodeType &= ~DSNode::AllocaNode;
+ { TIME_REGION(X, "cloneInto:scalars");
- // Copy the value map... and merge all of the global nodes...
- for (std::map<Value*, DSNodeHandle>::const_iterator I = G.ScalarMap.begin(),
+ // Copy the scalar map... merging all of the global nodes...
+ for (ScalarMapTy::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.setNode(MappedNode.getNode());
- H.setOffset(I->second.getOffset()+MappedNode.getOffset());
+ DSNodeHandle &H = OldValMap[I->first];
+ H.mergeWith(DSNodeHandle(MappedNode.getNode(),
+ I->second.getOffset()+MappedNode.getOffset()));
- if (isa<GlobalValue>(I->first)) { // Is this a global?
- std::map<Value*, DSNodeHandle>::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
- }
+ // 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);
+ InlinedGlobals.insert(GV);
}
}
+ }
if (!(CloneFlags & DontCloneCallNodes)) {
// Copy the function calls list...
}
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)
AuxFunctionCalls.push_back(DSCallSite(G.AuxFunctionCalls[i], OldNodeMap));
}
- // Return the returned node pointer...
- DSNodeHandle &MappedRet = OldNodeMap[G.RetNode.getNode()];
- return DSNodeHandle(MappedRet.getNode(),
- MappedRet.getOffset()+G.RetNode.getOffset());
+ // Map the return node pointers over...
+ for (ReturnNodesTy::const_iterator I = G.getReturnNodes().begin(),
+ E = G.getReturnNodes().end(); I != E; ++I) {
+ const DSNodeHandle &Ret = I->second;
+ DSNodeHandle &MappedRet = OldNodeMap[Ret.getNode()];
+ OldReturnNodes.insert(std::make_pair(I->first,
+ DSNodeHandle(MappedRet.getNode(),
+ MappedRet.getOffset()+Ret.getOffset())));
+ }
+}
+
+/// clonePartiallyInto - Clone the reachable subset of the specified DSGraph
+/// into the current graph, for the specified function.
+///
+/// This differs from cloneInto in that it only clones nodes reachable from
+/// globals, call nodes, the scalars specified in ValBindings, and the return
+/// value of the specified function. This method merges the the cloned
+/// version of the scalars and return value with the specified DSNodeHandles.
+///
+/// On return, OldNodeMap contains a mapping from the original nodes to the
+/// newly cloned nodes, for the subset of nodes that were actually cloned.
+///
+/// The CloneFlags member controls various aspects of the cloning process.
+///
+void DSGraph::clonePartiallyInto(const DSGraph &G, Function &F,
+ const DSNodeHandle &RetVal,
+ const ScalarMapTy &ValBindings,
+ NodeMapTy &OldNodeMap,
+ unsigned CloneFlags) {
+
+ TIME_REGION(X, "clonePartiallyInto");
+ assert(OldNodeMap.empty() && "Returned OldNodeMap should be empty!");
+ assert(&G != this && "Cannot clone graph into itself!");
+
+ unsigned FN = Nodes.size(); // First new node...
+
+ /// FIXME: This currently clones the whole graph over, instead of doing it
+ /// incrementally. This could be sped up quite a bit further!
+
+ // 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)
+ | ((CloneFlags & StripIncompleteBit)? DSNode::Incomplete : 0);
+ BitsToClear |= DSNode::DEAD; // Clear dead flag...
+
+ GlobalSetTy ClonedGlobals;
+ for (unsigned i = 0, e = G.Nodes.size(); i != e; ++i) {
+ DSNode *Old = G.Nodes[i];
+ DSNode *New = new DSNode(*Old, this);
+ New->maskNodeTypes(~BitsToClear);
+ OldNodeMap[Old] = New;
+
+ ClonedGlobals.insert(New->getGlobals().begin(), New->getGlobals().end());
+ }
+#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);
+
+ // Ensure that all global nodes end up in the scalar map, as appropriate.
+ for (GlobalSetTy::iterator CI = ClonedGlobals.begin(),
+ E = ClonedGlobals.end(); CI != E; ++CI) {
+ const DSNodeHandle &NGH = G.ScalarMap.find(*CI)->second;
+
+ DSNodeHandle &MappedNode = OldNodeMap[NGH.getNode()];
+ DSNodeHandle H(MappedNode.getNode(),NGH.getOffset()+MappedNode.getOffset());
+ ScalarMap[*CI].mergeWith(H);
+ InlinedGlobals.insert(*CI);
+ }
+
+ // Merge the requested portion of the scalar map with the values specified.
+ for (ScalarMapTy::const_iterator I = ValBindings.begin(),
+ E = ValBindings.end(); I != E; ++I) {
+ ScalarMapTy::const_iterator SMI = G.ScalarMap.find(I->first);
+ assert(SMI != G.ScalarMap.end() && "Cannot map non-existant scalar!");
+
+ DSNodeHandle &MappedNode = OldNodeMap[SMI->second.getNode()];
+ DSNodeHandle H(MappedNode.getNode(),
+ SMI->second.getOffset()+MappedNode.getOffset());
+ H.mergeWith(I->second);
+ }
+
+ // Map the return node pointer over.
+ if (RetVal.getNode()) {
+ const DSNodeHandle &Ret = G.getReturnNodeFor(F);
+ DSNodeHandle &MappedRet = OldNodeMap[Ret.getNode()];
+ DSNodeHandle H(MappedRet.getNode(),
+ MappedRet.getOffset()+Ret.getOffset());
+ H.mergeWith(RetVal);
+ }
+
+ // If requested, copy the calls or aux-calls lists.
+ if (!(CloneFlags & DontCloneCallNodes)) {
+ // Copy the function calls list...
+ unsigned FC = FunctionCalls.size(); // FirstCall
+ FunctionCalls.reserve(FC+G.FunctionCalls.size());
+ for (unsigned i = 0, ei = G.FunctionCalls.size(); i != ei; ++i)
+ FunctionCalls.push_back(DSCallSite(G.FunctionCalls[i], OldNodeMap));
+ }
+
+ if (!(CloneFlags & DontCloneAuxCallNodes)) {
+ // 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)
+ AuxFunctionCalls.push_back(DSCallSite(G.AuxFunctionCalls[i], OldNodeMap));
+ }
}
+
+
+
/// 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, const DSGraph &Graph,
- unsigned CloneFlags) {
- std::map<Value*, DSNodeHandle> OldValMap;
- DSNodeHandle RetVal;
- std::map<Value*, DSNodeHandle> *ScalarMap = &OldValMap;
-
+void DSGraph::mergeInGraph(const DSCallSite &CS, Function &F,
+ const DSGraph &Graph, unsigned CloneFlags) {
// 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.
- std::map<const DSNode*, DSNodeHandle> OldNodeMap;
+ ScalarMapTy ValueBindings;
+
+ // 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
+ if (AI == F.aend())
+ 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.
+ ValueBindings[AI] = CS.getPtrArg(i);
+ }
- // The clone call may invalidate any of the vectors in the data
- // structure graph. Strip locals and don't copy the list of callers
- RetVal = cloneInto(Graph, OldValMap, OldNodeMap, CloneFlags);
- ScalarMap = &OldValMap;
- } else {
- RetVal = getRetNode();
- ScalarMap = &getScalarMap();
- }
+ NodeMapTy OldNodeMap;
+ clonePartiallyInto(Graph, F, CS.getRetVal(), ValueBindings, OldNodeMap,
+ CloneFlags);
- // Merge the return value with the return value of the context...
- RetVal.mergeWith(CS.getRetVal());
+ } else {
+ DSNodeHandle RetVal = getReturnNodeFor(F);
+ ScalarMapTy &ScalarMap = getScalarMap();
- // Resolve all of the function arguments...
- Function &F = Graph.getFunction();
- 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 (!isPointerType(AI->getType())) {
- ++AI;
+ // 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
- if (AI == F.aend())
- std::cerr << "Bad call to Function: " << F.getName() << "\n";
+ if (AI == F.aend())
+ std::cerr << "Bad call to Function: " << F.getName() << "\n";
#endif
- assert(AI != F.aend() && "# Args provided is not # Args required!");
+ }
+ 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));
}
-
- // Add the link from the argument scalar to the provided value
- DSNodeHandle &NH = (*ScalarMap)[AI];
- assert(NH.getNode() && "Pointer argument without scalarmap entry?");
- NH.mergeWith(CS.getPtrArg(i));
}
}
-#if 0
-// cloneGlobalInto - Clone the given global node and all its target links
-// (and all their llinks, recursively).
-//
-DSNode *DSGraph::cloneGlobalInto(const DSNode *GNode) {
- if (GNode == 0 || GNode->getGlobals().size() == 0) return 0;
-
- // If a clone has already been created for GNode, return it.
- DSNodeHandle& ValMapEntry = ScalarMap[GNode->getGlobals()[0]];
- if (ValMapEntry != 0)
- return ValMapEntry;
-
- // Clone the node and update the ValMap.
- DSNode* NewNode = new DSNode(*GNode);
- ValMapEntry = NewNode; // j=0 case of loop below!
- Nodes.push_back(NewNode);
- for (unsigned j = 1, N = NewNode->getGlobals().size(); j < N; ++j)
- ScalarMap[NewNode->getGlobals()[j]] = NewNode;
-
- // Rewrite the links in the new node to point into the current graph.
- for (unsigned j = 0, e = GNode->getNumLinks(); j != e; ++j)
- NewNode->setLink(j, cloneGlobalInto(GNode->getLink(j)));
-
- return NewNode;
+/// 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);
}
-#endif
+
// markIncompleteNodes - Mark the specified node as having contents that are not
// known with the current analysis we have performed. Because a node makes all
-// of the nodes it can reach imcomplete if the node itself is incomplete, we
+// of the nodes it can reach incomplete if the node itself is incomplete, we
// must recursively traverse the data structure graph, marking all reachable
// nodes as incomplete.
//
static void markIncompleteNode(DSNode *N) {
// Stop recursion if no node, or if node already marked...
- if (N == 0 || (N->NodeType & DSNode::Incomplete)) return;
+ if (N == 0 || N->isIncomplete()) return;
// Actually mark the node
- N->NodeType |= DSNode::Incomplete;
+ 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);
}
+static void markIncomplete(DSCallSite &Call) {
+ // Then the return value is certainly incomplete!
+ markIncompleteNode(Call.getRetVal().getNode());
+
+ // All objects pointed to by function arguments are incomplete!
+ for (unsigned i = 0, e = Call.getNumPtrArgs(); i != e; ++i)
+ markIncompleteNode(Call.getPtrArg(i).getNode());
+}
// markIncompleteNodes - Traverse the graph, identifying nodes that may be
// modified by other functions that have not been resolved yet. This marks
// scope of current analysis may have modified it), the 'Incomplete' flag is
// added to the NodeType.
//
-void DSGraph::markIncompleteNodes(bool markFormalArgs) {
+void DSGraph::markIncompleteNodes(unsigned Flags) {
// Mark any incoming arguments as incomplete...
- if (markFormalArgs && Func)
- for (Function::aiterator I = Func->abegin(), E = Func->aend(); I != E; ++I)
- if (isPointerType(I->getType()) && ScalarMap.find(I) != ScalarMap.end())
- markIncompleteNode(ScalarMap[I].getNode());
+ if (Flags & DSGraph::MarkFormalArgs)
+ for (ReturnNodesTy::iterator FI = ReturnNodes.begin(), E =ReturnNodes.end();
+ FI != E; ++FI) {
+ 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());
+ }
// Mark stuff passed into functions calls as being incomplete...
- for (unsigned i = 0, e = FunctionCalls.size(); i != e; ++i) {
- DSCallSite &Call = FunctionCalls[i];
- // Then the return value is certainly incomplete!
- markIncompleteNode(Call.getRetVal().getNode());
-
- // All objects pointed to by function arguments are incomplete though!
- for (unsigned i = 0, e = Call.getNumPtrArgs(); i != e; ++i)
- markIncompleteNode(Call.getPtrArg(i).getNode());
- }
+ if (!shouldPrintAuxCalls())
+ for (unsigned i = 0, e = FunctionCalls.size(); i != e; ++i)
+ markIncomplete(FunctionCalls[i]);
+ else
+ for (unsigned i = 0, e = AuxFunctionCalls.size(); i != e; ++i)
+ markIncomplete(AuxFunctionCalls[i]);
+
- // Mark all of the nodes pointed to by global nodes as incomplete...
- for (unsigned i = 0, e = Nodes.size(); i != e; ++i)
- if (Nodes[i]->NodeType & DSNode::GlobalNode) {
- DSNode *N = Nodes[i];
- // FIXME: Make more efficient by looking over Links directly
- for (unsigned i = 0, e = N->getSize(); i < e; i += DS::PointerSize)
- if (DSNode *DSN = N->getLink(i).getNode())
- markIncompleteNode(DSN);
- }
+ // 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]);
}
-// removeRefsToGlobal - Helper function that removes globals from the
-// ScalarMap so that the referrer count will go down to zero.
-static void removeRefsToGlobal(DSNode* N,
- std::map<Value*, DSNodeHandle> &ScalarMap) {
- while (!N->getGlobals().empty()) {
- GlobalValue *GV = N->getGlobals().back();
- N->getGlobals().pop_back();
- ScalarMap.erase(GV);
- }
+static inline void killIfUselessEdge(DSNodeHandle &Edge) {
+ if (DSNode *N = Edge.getNode()) // Is there an edge?
+ if (N->getNumReferrers() == 1) // Does it point to a lonely node?
+ // No interesting info?
+ if ((N->getNodeFlags() & ~DSNode::Incomplete) == 0 &&
+ N->getType() == Type::VoidTy && !N->isNodeCompletelyFolded())
+ Edge.setNode(0); // Kill the edge!
}
-
-// isNodeDead - This method checks to see if a node is dead, and if it isn't, it
-// checks to see if there are simple transformations that it can do to make it
-// dead.
-//
-bool DSGraph::isNodeDead(DSNode *N) {
- // Is it a trivially dead shadow node...
- if (N->getReferrers().empty() &&
- (N->NodeType == 0 || N->NodeType == DSNode::DEAD))
- return true;
-
- // Is it a function node or some other trivially unused global?
- if ((N->NodeType & ~DSNode::GlobalNode) == 0 && N->getSize() == 0 &&
- N->getReferrers().size() == N->getGlobals().size()) {
-
- // Remove the globals from the ScalarMap, so that the referrer count will go
- // down to zero.
- removeRefsToGlobal(N, ScalarMap);
- assert(N->getReferrers().empty() && "Referrers should all be gone now!");
- return true;
- }
-
+static inline bool nodeContainsExternalFunction(const DSNode *N) {
+ const std::vector<GlobalValue*> &Globals = N->getGlobals();
+ for (unsigned i = 0, e = Globals.size(); i != e; ++i)
+ if (Globals[i]->isExternal())
+ return true;
return false;
}
-static void removeIdenticalCalls(vector<DSCallSite> &Calls,
- const std::string &where) {
+static void removeIdenticalCalls(std::vector<DSCallSite> &Calls) {
+
// Remove trivially identical function calls
unsigned NumFns = Calls.size();
- std::sort(Calls.begin(), Calls.end());
- Calls.erase(std::unique(Calls.begin(), Calls.end()),
- Calls.end());
+ std::sort(Calls.begin(), Calls.end()); // Sort by callee as primary key!
+
+ // Scan the call list cleaning it up as necessary...
+ DSNode *LastCalleeNode = 0;
+ Function *LastCalleeFunc = 0;
+ unsigned NumDuplicateCalls = 0;
+ bool LastCalleeContainsExternalFunction = false;
+ for (unsigned i = 0; i != Calls.size(); ++i) {
+ DSCallSite &CS = Calls[i];
+
+ // 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.swap(Calls.back());
+ Calls.pop_back();
+ --i;
+ } else {
+ // If the return value or any arguments point to a void node with no
+ // information at all in it, and the call node is the only node to point
+ // to it, remove the edge to the node (killing the node).
+ //
+ killIfUselessEdge(CS.getRetVal());
+ for (unsigned a = 0, e = CS.getNumPtrArgs(); a != e; ++a)
+ killIfUselessEdge(CS.getPtrArg(a));
+
+ // If this call site calls the same function as the last call site, and if
+ // the function pointer contains an external function, this node will
+ // never be resolved. Merge the arguments of the call node because no
+ // information will be lost.
+ //
+ if ((CS.isDirectCall() && CS.getCalleeFunc() == LastCalleeFunc) ||
+ (CS.isIndirectCall() && CS.getCalleeNode() == LastCalleeNode)) {
+ ++NumDuplicateCalls;
+ if (NumDuplicateCalls == 1) {
+ if (LastCalleeNode)
+ LastCalleeContainsExternalFunction =
+ nodeContainsExternalFunction(LastCalleeNode);
+ else
+ LastCalleeContainsExternalFunction = LastCalleeFunc->isExternal();
+ }
+
+#if 1
+ if (LastCalleeContainsExternalFunction ||
+ // This should be more than enough context sensitivity!
+ // FIXME: Evaluate how many times this is tripped!
+ NumDuplicateCalls > 20) {
+ DSCallSite &OCS = Calls[i-1];
+ OCS.mergeWith(CS);
+
+ // The node will now be eliminated as a duplicate!
+ if (CS.getNumPtrArgs() < OCS.getNumPtrArgs())
+ CS = OCS;
+ else if (CS.getNumPtrArgs() > OCS.getNumPtrArgs())
+ OCS = CS;
+ }
+#endif
+ } else {
+ if (CS.isDirectCall()) {
+ LastCalleeFunc = CS.getCalleeFunc();
+ LastCalleeNode = 0;
+ } else {
+ LastCalleeNode = CS.getCalleeNode();
+ LastCalleeFunc = 0;
+ }
+ NumDuplicateCalls = 0;
+ }
+ }
+ }
+
+ Calls.erase(std::unique(Calls.begin(), Calls.end()), Calls.end());
// Track the number of call nodes merged away...
NumCallNodesMerged += NumFns-Calls.size();
DEBUG(if (NumFns != Calls.size())
- std::cerr << "Merged " << (NumFns-Calls.size())
- << " call nodes in " << where << "\n";);
+ std::cerr << "Merged " << (NumFns-Calls.size()) << " call nodes.\n";);
}
+
// removeTriviallyDeadNodes - After the graph has been constructed, this method
// removes all unreachable nodes that are created because they got merged with
// other nodes in the graph. These nodes will all be trivially unreachable, so
// we don't have to perform any non-trivial analysis here.
//
-void DSGraph::removeTriviallyDeadNodes(bool KeepAllGlobals) {
- for (unsigned i = 0; i != Nodes.size(); ++i)
- if (!KeepAllGlobals || !(Nodes[i]->NodeType & DSNode::GlobalNode))
- if (isNodeDead(Nodes[i])) { // This node is dead!
- delete Nodes[i]; // Free memory...
- Nodes.erase(Nodes.begin()+i--); // Remove from node list...
- }
-
- removeIdenticalCalls(FunctionCalls, Func ? Func->getName() : "");
-}
+void DSGraph::removeTriviallyDeadNodes() {
+ TIME_REGION(X, "removeTriviallyDeadNodes");
+
+ 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. While we are at it,
+ // clean house a bit.
+ for (ScalarMapTy::iterator I = ScalarMap.begin(),E = ScalarMap.end();I != E;){
+ // 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
+ // NOT used as a pointer, we can delete the node. We will be able to detect
+ // this situation if the node pointed to ONLY has Unknown bit set in the
+ // node. In this case, the node is not incomplete, does not point to any
+ // other nodes (no mod/ref bits set), and is therefore 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->getNodeFlags() == DSNode::UnknownNode && !isa<Argument>(I->first))
+ ScalarMap.erase(I++);
+ else
+ ++I;
+ }
-// markAlive - Simple graph walker that recursively traverses the graph, marking
-// stuff to be alive.
-//
-static void markAlive(DSNode *N, std::set<DSNode*> &Alive) {
- if (N == 0) return;
+ bool isGlobalsGraph = !GlobalsGraph;
- Alive.insert(N);
- for (unsigned i = 0, e = N->getSize(); i < e; i += DS::PointerSize)
- if (DSNode *DSN = N->getLink(i).getNode())
- if (!Alive.count(DSN))
- markAlive(DSN, Alive);
-}
+ for (unsigned i = 0; i != Nodes.size(); ++i) {
+ DSNode *Node = Nodes[i];
-static bool checkGlobalAlive(DSNode *N, std::set<DSNode*> &Alive,
- std::set<DSNode*> &Visiting) {
- if (N == 0) return false;
-
- if (Visiting.count(N)) return false; // terminate recursion on a cycle
- Visiting.insert(N);
+ // 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 any immediate successor is alive, N is alive
- for (unsigned i = 0, e = N->getSize(); i < e; i += DS::PointerSize)
- if (DSNode *DSN = N->getLink(i).getNode())
- if (Alive.count(DSN)) {
- Visiting.erase(N);
- return true;
- }
+ 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();
+
+ // 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!");
+ }
- // Else if any successor reaches a live node, N is alive
- for (unsigned i = 0, e = N->getSize(); i < e; i += DS::PointerSize)
- if (DSNode *DSN = N->getLink(i).getNode())
- if (checkGlobalAlive(DSN, Alive, Visiting)) {
- Visiting.erase(N); return true;
+ // Make sure NumReferrers still agrees, if so, the node is truly dead.
+ if (Node->getNumReferrers() == Globals.size()) {
+ for (unsigned j = 0, e = Globals.size(); j != e; ++j)
+ ScalarMap.erase(Globals[j]);
+ Node->makeNodeDead();
+ }
}
- Visiting.erase(N);
- return false;
-}
-
-
-// markGlobalsIteration - Recursive helper function for markGlobalsAlive().
-// This would be unnecessary if function calls were real nodes! In that case,
-// the simple iterative loop in the first few lines below suffice.
-//
-static void markGlobalsIteration(std::set<DSNode*>& GlobalNodes,
- vector<DSCallSite> &Calls,
- std::set<DSNode*> &Alive,
- bool FilterCalls) {
-
- // Iterate, marking globals or cast nodes alive until no new live nodes
- // are added to Alive
- std::set<DSNode*> Visiting; // Used to identify cycles
- std::set<DSNode*>::iterator I = GlobalNodes.begin(), E = GlobalNodes.end();
- for (size_t liveCount = 0; liveCount < Alive.size(); ) {
- liveCount = Alive.size();
- for ( ; I != E; ++I)
- if (Alive.count(*I) == 0) {
- Visiting.clear();
- if (checkGlobalAlive(*I, Alive, Visiting))
- markAlive(*I, Alive);
- }
- }
+#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();
- // Find function calls with some dead and some live nodes.
- // Since all call nodes must be live if any one is live, we have to mark
- // all nodes of the call as live and continue the iteration (via recursion).
- if (FilterCalls) {
- bool Recurse = false;
- for (unsigned i = 0, ei = Calls.size(); i < ei; ++i) {
- bool CallIsDead = true, CallHasDeadArg = false;
- DSCallSite &CS = Calls[i];
- for (unsigned j = 0, ej = CS.getNumPtrArgs(); j != ej; ++j)
- if (DSNode *N = CS.getPtrArg(j).getNode()) {
- bool ArgIsDead = !Alive.count(N);
- CallHasDeadArg |= ArgIsDead;
- CallIsDead &= ArgIsDead;
+#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
- if (DSNode *N = CS.getRetVal().getNode()) {
- bool RetIsDead = !Alive.count(N);
- CallHasDeadArg |= RetIsDead;
- CallIsDead &= RetIsDead;
+ // 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
+ }
- DSNode *N = CS.getCallee().getNode();
- bool FnIsDead = !Alive.count(N);
- CallHasDeadArg |= FnIsDead;
- CallIsDead &= FnIsDead;
-
- if (!CallIsDead && CallHasDeadArg) {
- // Some node in this call is live and another is dead.
- // Mark all nodes of call as live and iterate once more.
- Recurse = true;
- for (unsigned j = 0, ej = CS.getNumPtrArgs(); j != ej; ++j)
- markAlive(CS.getPtrArg(j).getNode(), Alive);
- markAlive(CS.getRetVal().getNode(), Alive);
- markAlive(CS.getCallee().getNode(), Alive);
- }
+ 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...
}
- if (Recurse)
- markGlobalsIteration(GlobalNodes, Calls, Alive, FilterCalls);
}
}
-// markGlobalsAlive - Mark global nodes and cast nodes alive if they
-// can reach any other live node. Since this can produce new live nodes,
-// we use a simple iterative algorithm.
-//
-static void markGlobalsAlive(DSGraph &G, std::set<DSNode*> &Alive,
- bool FilterCalls) {
- // Add global and cast nodes to a set so we don't walk all nodes every time
- std::set<DSNode*> GlobalNodes;
- for (unsigned i = 0, e = G.getNodes().size(); i != e; ++i)
- if (G.getNodes()[i]->NodeType & DSNode::GlobalNode)
- GlobalNodes.insert(G.getNodes()[i]);
-
- // Add all call nodes to the same set
- vector<DSCallSite> &Calls = G.getAuxFunctionCalls();
- if (FilterCalls) {
- for (unsigned i = 0, e = Calls.size(); i != e; ++i) {
- for (unsigned j = 0, e = Calls[i].getNumPtrArgs(); j != e; ++j)
- if (DSNode *N = Calls[i].getPtrArg(j).getNode())
- GlobalNodes.insert(N);
- if (DSNode *N = Calls[i].getRetVal().getNode())
- GlobalNodes.insert(N);
- if (DSNode *N = Calls[i].getCallee().getNode())
- GlobalNodes.insert(N);
- }
- }
+/// markReachableNodes - This method recursively traverses the specified
+/// DSNodes, marking any nodes which are reachable. All reachable nodes it adds
+/// to the set, which allows it to only traverse visited nodes once.
+///
+void DSNode::markReachableNodes(hash_set<DSNode*> &ReachableNodes) {
+ if (this == 0) return;
+ assert(getForwardNode() == 0 && "Cannot mark a forwarded node!");
+ 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) {
+ getRetVal().getNode()->markReachableNodes(Nodes);
+ if (isIndirectCall()) getCalleeNode()->markReachableNodes(Nodes);
+
+ for (unsigned i = 0, e = getNumPtrArgs(); i != e; ++i)
+ getPtrArg(i).getNode()->markReachableNodes(Nodes);
+}
- // Iterate and recurse until no new live node are discovered.
- // This would be a simple iterative loop if function calls were real nodes!
- markGlobalsIteration(GlobalNodes, Calls, Alive, FilterCalls);
-
- // Free up references to dead globals from the ScalarMap
- std::set<DSNode*>::iterator I = GlobalNodes.begin(), E = GlobalNodes.end();
- for( ; I != E; ++I)
- if (Alive.count(*I) == 0)
- removeRefsToGlobal(*I, G.getScalarMap());
-
- // Delete dead function calls
- if (FilterCalls)
- for (int ei = Calls.size(), i = ei-1; i >= 0; --i) {
- bool CallIsDead = true;
- for (unsigned j = 0, ej = Calls[i].getNumPtrArgs();
- CallIsDead && j != ej; ++j)
- CallIsDead = Alive.count(Calls[i].getPtrArg(j).getNode()) == 0;
- if (CallIsDead)
- Calls.erase(Calls.begin() + i); // remove the call entirely
+// CanReachAliveNodes - Simple graph walker that recursively traverses the graph
+// looking for a node that is marked alive. If an alive node is found, return
+// true, otherwise return false. If an alive node is reachable, this node is
+// marked as alive...
+//
+static bool CanReachAliveNodes(DSNode *N, hash_set<DSNode*> &Alive,
+ 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;
+
+ // Otherwise, we don't think the node is alive yet, check for infinite
+ // recursion.
+ if (Visited.count(N)) return false; // Found a cycle
+ 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,
+ IgnoreGlobals)) {
+ N->markReachableNodes(Alive);
+ return true;
}
+ return false;
+}
+
+// CallSiteUsesAliveArgs - Return true if the specified call site can reach any
+// alive nodes.
+//
+static bool CallSiteUsesAliveArgs(DSCallSite &CS, hash_set<DSNode*> &Alive,
+ hash_set<DSNode*> &Visited,
+ bool IgnoreGlobals) {
+ if (CanReachAliveNodes(CS.getRetVal().getNode(), Alive, Visited,
+ IgnoreGlobals))
+ return true;
+ if (CS.isIndirectCall() &&
+ 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,
+ IgnoreGlobals))
+ return true;
+ return false;
}
// removeDeadNodes - Use a more powerful reachability analysis to eliminate
// from the caller's graph entirely. This is only appropriate to use when
// inlining graphs.
//
-void DSGraph::removeDeadNodes(bool KeepAllGlobals, bool KeepCalls) {
- assert((!KeepAllGlobals || KeepCalls) && // FIXME: This should be an enum!
- "KeepAllGlobals without KeepCalls is meaningless");
+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();
- // Reduce the amount of work we have to do...
- removeTriviallyDeadNodes(KeepAllGlobals);
+ TIME_REGION(X, "removeDeadNodes");
- // 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.
- std::set<DSNode*> Alive;
-
- // If KeepCalls, mark all nodes reachable by call nodes as alive...
- if (KeepCalls) {
- for (unsigned i = 0, e = FunctionCalls.size(); i != e; ++i) {
- for (unsigned j = 0, e = FunctionCalls[i].getNumPtrArgs(); j != e; ++j)
- markAlive(FunctionCalls[i].getPtrArg(j).getNode(), Alive);
- markAlive(FunctionCalls[i].getRetVal().getNode(), Alive);
- markAlive(FunctionCalls[i].getCallee().getNode(), Alive);
+ hash_set<DSNode*> Alive;
+ std::vector<std::pair<Value*, DSNode*> > GlobalNodes;
+
+ // Mark all nodes reachable by (non-global) scalar nodes as alive...
+ for (ScalarMapTy::iterator I = ScalarMap.begin(), E = ScalarMap.end(); I != E;
+ ++I)
+ 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()));
+ } else {
+ I->second.getNode()->markReachableNodes(Alive);
}
- for (unsigned i = 0, e = AuxFunctionCalls.size(); i != e; ++i) {
- for (unsigned j = 0, e = AuxFunctionCalls[i].getNumPtrArgs(); j != e; ++j)
- markAlive(AuxFunctionCalls[i].getPtrArg(j).getNode(), Alive);
- markAlive(AuxFunctionCalls[i].getRetVal().getNode(), Alive);
- markAlive(AuxFunctionCalls[i].getCallee().getNode(), Alive);
- }
- }
-
- // Mark all nodes reachable by scalar nodes as alive...
- for (std::map<Value*, DSNodeHandle>::iterator I = ScalarMap.begin(),
- E = ScalarMap.end(); I != E; ++I)
- markAlive(I->second.getNode(), Alive);
// The return value is alive as well...
- markAlive(RetNode.getNode(), Alive);
-
- // Mark all globals or cast nodes that can reach a live node as alive.
- // This also marks all nodes reachable from such nodes as alive.
- // Of course, if KeepAllGlobals is specified, they would be live already.
+ for (ReturnNodesTy::iterator I = ReturnNodes.begin(), E = ReturnNodes.end();
+ I != E; ++I)
+ I->second.getNode()->markReachableNodes(Alive);
+
+ // Mark any nodes reachable by primary calls as 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 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;
+ 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] &&
+ (AuxFunctionCalls[i].isIndirectCall()
+ || CallSiteUsesAliveArgs(AuxFunctionCalls[i], Alive, Visited,
+ Flags & DSGraph::RemoveUnreachableGlobals))) {
+ AuxFunctionCalls[i].markReachableNodes(Alive);
+ AuxFCallsAlive[i] = true;
+ Iterate = true;
+ }
+ } while (Iterate);
+
+ // 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));
+ }
- if (!KeepAllGlobals)
- markGlobalsAlive(*this, Alive, !KeepCalls);
+ // Remove all dead aux function calls...
+ if (!(Flags & DSGraph::RemoveUnreachableGlobals)) {
+ assert(GlobalsGraph && "No globals graph available??");
- // Loop over all unreachable nodes, dropping their references...
- vector<DSNode*> DeadNodes;
- DeadNodes.reserve(Nodes.size()); // Only one allocation is allowed.
+ // 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());
+
+ // 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());
for (unsigned i = 0; i != Nodes.size(); ++i)
if (!Alive.count(Nodes[i])) {
DSNode *N = Nodes[i];
- Nodes.erase(Nodes.begin()+i--); // Erase node from alive list.
- DeadNodes.push_back(N); // Add node to our list of dead nodes
- N->dropAllReferences(); // Drop all outgoing edges
+ Nodes[i--] = Nodes.back(); // move node to end of vector
+ Nodes.pop_back(); // Erase node from alive list.
+ DeadNodes.push_back(N);
+ N->dropAllReferences();
+ } else {
+ assert(Nodes[i]->getForwardNode() == 0 && "Alive forwarded node?");
}
-
- // Delete all dead nodes...
- std::for_each(DeadNodes.begin(), DeadNodes.end(), deleter<DSNode>);
-}
-
-
-
-// maskNodeTypes - Apply a mask to all of the node types in the graph. This
-// is useful for clearing out markers like Scalar or Incomplete.
-//
-void DSGraph::maskNodeTypes(unsigned char Mask) {
- for (unsigned i = 0, e = Nodes.size(); i != e; ++i)
- Nodes[i]->NodeType &= Mask;
-}
-
-
-#if 0
-//===----------------------------------------------------------------------===//
-// GlobalDSGraph Implementation
-//===----------------------------------------------------------------------===//
-
-GlobalDSGraph::GlobalDSGraph() : DSGraph(*(Function*)0, this) {
-}
-GlobalDSGraph::~GlobalDSGraph() {
- assert(Referrers.size() == 0 &&
- "Deleting global graph while references from other graphs exist");
-}
+ // 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);
+ }
-void GlobalDSGraph::addReference(const DSGraph* referrer) {
- if (referrer != this)
- Referrers.insert(referrer);
-}
+ // 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 GlobalDSGraph::removeReference(const DSGraph* referrer) {
- if (referrer != this) {
- assert(Referrers.find(referrer) != Referrers.end() && "This is very bad!");
- Referrers.erase(referrer);
- if (Referrers.size() == 0)
- delete this;
- }
+ DEBUG(AssertGraphOK(); GlobalsGraph->AssertGraphOK());
}
-#if 0
-// Bits used in the next function
-static const char ExternalTypeBits = DSNode::GlobalNode | DSNode::HeapNode;
-
-
-// GlobalDSGraph::cloneNodeInto - Clone a global node and all its externally
-// visible target links (and recursively their such links) into this graph.
-// NodeCache maps the node being cloned to its clone in the Globals graph,
-// in order to track cycles.
-// GlobalsAreFinal is a flag that says whether it is safe to assume that
-// an existing global node is complete. This is important to avoid
-// reinserting all globals when inserting Calls to functions.
-// This is a helper function for cloneGlobals and cloneCalls.
-//
-DSNode* GlobalDSGraph::cloneNodeInto(DSNode *OldNode,
- std::map<const DSNode*, DSNode*> &NodeCache,
- bool GlobalsAreFinal) {
- if (OldNode == 0) return 0;
-
- // The caller should check this is an external node. Just more efficient...
- assert((OldNode->NodeType & ExternalTypeBits) && "Non-external node");
-
- // If a clone has already been created for OldNode, return it.
- DSNode*& CacheEntry = NodeCache[OldNode];
- if (CacheEntry != 0)
- return CacheEntry;
-
- // The result value...
- DSNode* NewNode = 0;
-
- // If nodes already exist for any of the globals of OldNode,
- // merge all such nodes together since they are merged in OldNode.
- // If ValueCacheIsFinal==true, look for an existing node that has
- // an identical list of globals and return it if it exists.
- //
- for (unsigned j = 0, N = OldNode->getGlobals().size(); j != N; ++j)
- if (DSNode *PrevNode = ScalarMap[OldNode->getGlobals()[j]].getNode()) {
- if (NewNode == 0) {
- NewNode = PrevNode; // first existing node found
- if (GlobalsAreFinal && j == 0)
- if (OldNode->getGlobals() == PrevNode->getGlobals()) {
- CacheEntry = NewNode;
- return NewNode;
- }
- }
- else if (NewNode != PrevNode) { // found another, different from prev
- // update ValMap *before* merging PrevNode into NewNode
- for (unsigned k = 0, NK = PrevNode->getGlobals().size(); k < NK; ++k)
- ScalarMap[PrevNode->getGlobals()[k]] = NewNode;
- NewNode->mergeWith(PrevNode);
- }
- } else if (NewNode != 0) {
- ScalarMap[OldNode->getGlobals()[j]] = NewNode; // add the merged node
- }
-
- // If no existing node was found, clone the node and update the ValMap.
- if (NewNode == 0) {
- NewNode = new DSNode(*OldNode);
- Nodes.push_back(NewNode);
- for (unsigned j = 0, e = NewNode->getNumLinks(); j != e; ++j)
- NewNode->setLink(j, 0);
- for (unsigned j = 0, N = NewNode->getGlobals().size(); j < N; ++j)
- ScalarMap[NewNode->getGlobals()[j]] = NewNode;
- }
- else
- NewNode->NodeType |= OldNode->NodeType; // Markers may be different!
-
- // Add the entry to NodeCache
- CacheEntry = NewNode;
-
- // Rewrite the links in the new node to point into the current graph,
- // but only for links to external nodes. Set other links to NULL.
- for (unsigned j = 0, e = OldNode->getNumLinks(); j != e; ++j) {
- DSNode* OldTarget = OldNode->getLink(j);
- if (OldTarget && (OldTarget->NodeType & ExternalTypeBits)) {
- DSNode* NewLink = this->cloneNodeInto(OldTarget, NodeCache);
- if (NewNode->getLink(j))
- NewNode->getLink(j)->mergeWith(NewLink);
- else
- NewNode->setLink(j, NewLink);
+void DSGraph::AssertGraphOK() const {
+ for (unsigned i = 0, e = Nodes.size(); i != e; ++i)
+ Nodes[i]->assertOK();
+
+ for (ScalarMapTy::const_iterator I = ScalarMap.begin(),
+ E = ScalarMap.end(); I != E; ++I) {
+ assert(I->second.getNode() && "Null node in scalarmap!");
+ AssertNodeInGraph(I->second.getNode());
+ if (GlobalValue *GV = dyn_cast<GlobalValue>(I->first)) {
+ assert(I->second.getNode()->isGlobalNode() &&
+ "Global points to node, but node isn't global?");
+ AssertNodeContainsGlobal(I->second.getNode(), GV);
}
}
-
- // Remove all local markers
- NewNode->NodeType &= ~(DSNode::AllocaNode | DSNode::ScalarNode);
-
- return NewNode;
+ AssertCallNodesInGraph();
+ AssertAuxCallNodesInGraph();
}
-
-// GlobalDSGraph::cloneGlobals - Clone global nodes and all their externally
-// visible target links (and recursively their such links) into this graph.
-//
-void GlobalDSGraph::cloneGlobals(DSGraph& Graph, bool CloneCalls) {
- std::map<const DSNode*, DSNode*> NodeCache;
-#if 0
- for (unsigned i = 0, N = Graph.Nodes.size(); i < N; ++i)
- if (Graph.Nodes[i]->NodeType & DSNode::GlobalNode)
- GlobalsGraph->cloneNodeInto(Graph.Nodes[i], NodeCache, false);
- if (CloneCalls)
- GlobalsGraph->cloneCalls(Graph);
-
- GlobalsGraph->removeDeadNodes(/*KeepAllGlobals*/ true, /*KeepCalls*/ true);
-#endif
+/// 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();
}
-// GlobalDSGraph::cloneCalls - Clone function calls and their visible target
-// links (and recursively their such links) into this graph.
-//
-void GlobalDSGraph::cloneCalls(DSGraph& Graph) {
- std::map<const DSNode*, DSNode*> NodeCache;
- vector<DSCallSite >& FromCalls =Graph.FunctionCalls;
-
- FunctionCalls.reserve(FunctionCalls.size() + FromCalls.size());
-
- for (int i = 0, ei = FromCalls.size(); i < ei; ++i) {
- DSCallSite& callCopy = FunctionCalls.back();
- callCopy.reserve(FromCalls[i].size());
- for (unsigned j = 0, ej = FromCalls[i].size(); j != ej; ++j)
- callCopy.push_back
- ((FromCalls[i][j] && (FromCalls[i][j]->NodeType & ExternalTypeBits))
- ? cloneNodeInto(FromCalls[i][j], NodeCache, true)
- : 0);
+/// 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!
+ assert(!StrictChecking ||
+ (Entry.getNode() == N2 &&
+ Entry.getOffset() == (NH2.getOffset()-NH1.getOffset())) &&
+ "Inconsistent mapping detected!");
+ return;
}
-
- // remove trivially identical function calls
- removeIdenticalCalls(FunctionCalls, "Globals Graph");
+
+ Entry.setNode(N2);
+ Entry.setOffset(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);
}
-#endif
-
-#endif