#include "llvm/Analysis/DSGraph.h"
#include "llvm/Function.h"
+#include "llvm/iOther.h"
#include "llvm/DerivedTypes.h"
#include "llvm/Target/TargetData.h"
#include "Support/STLExtras.h"
#include "Support/Statistic.h"
+#include "Support/Timer.h"
#include <algorithm>
#include <set>
using std::vector;
-// TODO: FIXME
-namespace DataStructureAnalysis {
- // isPointerType - Return true if this first class type is big enough to hold
- // a pointer.
- //
- bool isPointerType(const Type *Ty);
+namespace {
+ Statistic<> NumFolds ("dsnode", "Number of nodes completely folded");
+ Statistic<> NumCallNodesMerged("dsnode", "Number of call nodes merged");
+};
+
+namespace DS { // TODO: FIXME
extern TargetData TD;
}
-using namespace DataStructureAnalysis;
+using namespace DS;
//===----------------------------------------------------------------------===//
// DSNode Implementation
//===----------------------------------------------------------------------===//
-DSNode::DSNode(enum NodeTy NT, const Type *T) : NodeType(NT) {
- // If this node is big enough to have pointer fields, add space for them now.
- if (T != Type::VoidTy && !isa<FunctionType>(T)) { // Avoid TargetData assert's
- MergeMap.resize(TD.getTypeSize(T));
-
- // Assign unique values to all of the elements of MergeMap
- if (MergeMap.size() < 128) {
- // Handle the common case of reasonable size structures...
- for (unsigned i = 0, e = MergeMap.size(); i != e; ++i)
- MergeMap[i] = -1-i; // Assign -1, -2, -3, ...
- } else {
- // It's possible that we have something really big here. In this case,
- // divide the object into chunks until it will fit into 128 elements.
- unsigned Multiple = MergeMap.size()/128;
-
- // It's probably an array, and probably some power of two in size.
- // Because of this, find the biggest power of two that is bigger than
- // multiple to use as our real Multiple.
- unsigned RealMultiple = 2;
- while (RealMultiple <= Multiple) RealMultiple <<= 1;
-
- unsigned RealBound = MergeMap.size()/RealMultiple;
- assert(RealBound <= 128 && "Math didn't work out right");
-
- // Now go through and assign indexes that are between -1 and -128
- // inclusive
- //
- for (unsigned i = 0, e = MergeMap.size(); i != e; ++i)
- MergeMap[i] = -1-(i % RealBound); // Assign -1, -2, -3...
- }
- }
-
- TypeEntries.push_back(std::make_pair(T, 0));
+DSNode::DSNode(enum NodeTy NT, const Type *T)
+ : Ty(Type::VoidTy), Size(0), NodeType(NT) {
+ // Add the type entry if it is specified...
+ if (T) mergeTypeInfo(T, 0);
}
// DSNode copy constructor... do not copy over the referrers list!
DSNode::DSNode(const DSNode &N)
- : Links(N.Links), MergeMap(N.MergeMap),
- TypeEntries(N.TypeEntries), Globals(N.Globals), NodeType(N.NodeType) {
+ : Links(N.Links), Globals(N.Globals), Ty(N.Ty), Size(N.Size),
+ NodeType(N.NodeType) {
}
void DSNode::removeReferrer(DSNodeHandle *H) {
}
}
+/// foldNodeCompletely - If we determine that this node has some funny
+/// behavior happening to it that we cannot represent, we fold it down to a
+/// single, completely pessimistic, node. This node is represented as a
+/// single byte with a single TypeEntry of "void".
+///
+void DSNode::foldNodeCompletely() {
+ if (isNodeCompletelyFolded()) return;
+
+ ++NumFolds;
+
+ // We are no longer typed at all...
+ Ty = Type::VoidTy;
+ NodeType |= Array;
+ Size = 1;
+
+ // 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);
+}
+
+/// isNodeCompletelyFolded - Return true if this node has been completely
+/// folded down to something that can never be expanded, effectively losing
+/// all of the field sensitivity that may be present in the node.
+///
+bool DSNode::isNodeCompletelyFolded() const {
+ return getSize() == 1 && Ty == Type::VoidTy && isArray();
+}
+
-/// setLink - Set the link at the specified offset to the specified
-/// NodeHandle, replacing what was there. It is uncommon to use this method,
-/// instead one of the higher level methods should be used, below.
+/// mergeTypeInfo - This method merges the specified type into the current node
+/// at the specified offset. This may update the current node's type record if
+/// this gives more information to the node, it may do nothing to the node if
+/// this information is already known, or it may merge the node completely (and
+/// return true) if the information is incompatible with what is already known.
///
-void DSNode::setLink(unsigned i, const DSNodeHandle &NH) {
- // Create a new entry in the Links vector to hold a new element for offset.
- if (!hasLink(i)) {
- signed char NewIdx = Links.size();
- // Check to see if we allocate more than 128 distinct links for this node.
- // If so, just merge with the last one. This really shouldn't ever happen,
- // but it should work regardless of whether it does or not.
+/// This method returns true if the node is completely folded, otherwise false.
+///
+bool DSNode::mergeTypeInfo(const Type *NewTy, unsigned Offset) {
+ // 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 = 0, Ty = FnTy: FunctionPtr doesn't have a size, so we use zero
+ // Size = 1, Ty = Void, Array = 1: The node is collapsed
+ // Otherwise, sizeof(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)
+ 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;
+
+ // Otherwise check to see if we can fold this type into the current node. If
+ // we can't, we fold the node completely, if we can, we potentially update our
+ // internal state.
+ //
+ 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!");
+ Ty = NewTy;
+ NodeType &= ~Array;
+ if (WillBeArray) NodeType |= Array;
+ Size = NewTySize;
+
+ // Calculate the number of outgoing links from this node.
+ Links.resize((Size+DS::PointerSize-1) >> DS::PointerShift);
+ return false;
+ }
+
+ // Handle node expansion case here...
+ if (Offset+NewTySize > Size) {
+ // It is illegal to grow this node if we have treated it as an array of
+ // objects...
+ if (isArray()) {
+ 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();
+ return true;
+ }
+
+ // Okay, the situation is nice and simple, we are trying to merge a type in
+ // at offset 0 that is bigger than our current type. Implement this by
+ // switching to the new type and then merge in the smaller one, which should
+ // hit the other code path here. If the other code path decides it's not
+ // ok, it will collapse the node as appropriate.
//
- if (NewIdx >= 0) {
- Links.push_back(NH); // Allocate space: common case
- } else { // Wrap around? Too many links?
- NewIdx--; // Merge with whatever happened last
- assert(NewIdx > 0 && "Should wrap back around");
- std::cerr << "\n*** DSNode found that requires more than 128 "
- << "active links at once!\n\n";
- }
-
- signed char OldIdx = MergeMap[i];
- assert (OldIdx < 0 && "Shouldn't contain link!");
-
- // Make sure that anything aliasing this field gets updated to point to the
- // new link field.
- rewriteMergeMap(OldIdx, NewIdx);
- assert(MergeMap[i] == NewIdx && "Field not replaced!");
- } else {
- Links[MergeMap[i]] = NH;
+ const Type *OldTy = Ty;
+ Ty = NewTy;
+ NodeType &= ~Array;
+ if (WillBeArray) NodeType |= Array;
+ Size = NewTySize;
+
+ // Must grow links to be the appropriate size...
+ Links.resize((Size+DS::PointerSize-1) >> DS::PointerShift);
+
+ // Merge in the old type now... which is guaranteed to be smaller than the
+ // "current" type.
+ return mergeTypeInfo(OldTy, 0);
+ }
+
+ assert(Offset <= Size &&
+ "Cannot merge something into a part of our type that doesn't exist!");
+
+ // 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;
+ while (O < Offset) {
+ assert(Offset-O < TD.getTypeSize(SubType) && "Offset out of range!");
+
+ switch (SubType->getPrimitiveID()) {
+ case Type::StructTyID: {
+ const StructType *STy = cast<StructType>(SubType);
+ const StructLayout &SL = *TD.getStructLayout(STy);
+
+ unsigned i = 0, e = SL.MemberOffsets.size();
+ for (; i+1 < e && SL.MemberOffsets[i+1] <= Offset-O; ++i)
+ /* empty */;
+
+ // The offset we are looking for must be in the i'th element...
+ SubType = STy->getElementTypes()[i];
+ O += SL.MemberOffsets[i];
+ break;
+ }
+ case Type::ArrayTyID: {
+ SubType = cast<ArrayType>(SubType)->getElementType();
+ unsigned ElSize = TD.getTypeSize(SubType);
+ unsigned Remainder = (Offset-O) % ElSize;
+ O = Offset-Remainder;
+ break;
+ }
+ default:
+ assert(0 && "Unknown type!");
+ }
}
+
+ assert(O == Offset && "Could not achieve the correct offset!");
+
+ // If we found our type exactly, early exit
+ if (SubType == NewTy) 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 = 0;
+ unsigned NextPadSize = 0;
+ switch (SubType->getPrimitiveID()) {
+ 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(NextSubType);
+ NextPadSize = NextSubTypeSize;
+ break;
+ default: ;
+ // fall out
+ }
+
+ if (NextSubType == 0)
+ break; // In the default case, break out of the loop
+
+ 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...
+ if (SubType == NewTy)
+ return false;
+
+ // 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))
+ return false;
+
+ // Check to see if we have a pointer & integer mismatch going on here,
+ // loading a pointer as a long, for example.
+ //
+ 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;
+ }
+
+
+ DEBUG(std::cerr << "MergeTypeInfo Folding OrigTy: " << Ty
+ << "\n due to:" << NewTy << " @ " << Offset << "!\n"
+ << "SubType: " << SubType << "\n\n");
+
+ foldNodeCompletely();
+ return true;
}
+
+
// 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) {
- assert(Offset < getSize() && "Offset out of range!");
if (NH.getNode() == 0) return; // Nothing to do
- if (DSNodeHandle *ExistingNH = getLink(Offset)) {
+ DSNodeHandle &ExistingEdge = getLink(Offset);
+ if (ExistingEdge.getNode()) {
// Merge the two nodes...
- ExistingNH->mergeWith(NH);
+ ExistingEdge.mergeWith(NH);
} else { // No merging to perform...
setLink(Offset, NH); // Just force a link in there...
}
}
-/// mergeMappedValues - This is the higher level form of rewriteMergeMap. It is
-/// fully capable of merging links together if neccesary as well as simply
-/// rewriting the map entries.
-///
-void DSNode::mergeMappedValues(signed char V1, signed char V2) {
- assert(V1 != V2 && "Cannot merge two identical mapped values!");
-
- if (V1 < 0) { // If there is no outgoing link from V1, merge it with V2
- if (V2 < 0 && V1 > V2)
- // If both are not linked, merge to the field closer to 0
- rewriteMergeMap(V2, V1);
- else
- rewriteMergeMap(V1, V2);
- } else if (V2 < 0) { // Is V2 < 0 && V1 >= 0?
- rewriteMergeMap(V2, V1); // Merge into the one with the link...
- } else { // Otherwise, links exist at both locations
- // Merge Links[V1] with Links[V2] so they point to the same place now...
- Links[V1].mergeWith(Links[V2]);
-
- // Merge the V2 link into V1 so that we reduce the overall value of the
- // links are reduced...
- //
- if (V2 < V1) std::swap(V1, V2); // Ensure V1 < V2
- rewriteMergeMap(V2, V1); // After this, V2 is "dead"
-
- // Change the user of the last link to use V2 instead
- if ((unsigned)V2 != Links.size()-1) {
- rewriteMergeMap(Links.size()-1, V2); // Point to V2 instead of last el...
- // Make sure V2 points the right DSNode
- Links[V2] = Links.back();
- }
-
- // Reduce the number of distinct outgoing links...
- Links.pop_back();
- }
-}
-
// 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.
//
-template<typename T>
-void MergeSortedVectors(vector<T> &Dest, const vector<T> &Src) {
+static void MergeSortedVectors(vector<GlobalValue*> &Dest,
+ const 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];
+ 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]);
+ 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);
+ vector<GlobalValue*> Old(Dest);
// Make space for all of the type entries now...
Dest.resize(Dest.size()+Src.size());
void DSNode::mergeWith(const DSNodeHandle &NH, unsigned Offset) {
DSNode *N = NH.getNode();
if (N == 0 || (N == this && NH.getOffset() == Offset))
- return; // Noop
-
- assert(NH.getNode() != this &&
- "Cannot merge two portions of the same node yet!");
+ return; // Noop
+
+ assert((N->NodeType & DSNode::DEAD) == 0);
+ assert((NodeType & DSNode::DEAD) == 0);
+ assert(!hasNoReferrers() && "Should not try to fold a useless node!");
+
+ if (N == this) {
+ // We cannot merge two pieces of the same node together, collapse the node
+ // completely.
+ DEBUG(std::cerr << "Attempting to merge two chunks of"
+ << " the same node together!\n");
+ foldNodeCompletely();
+ return;
+ }
// 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()) {
+ // If the offsets are the same, merge the smaller node into the bigger node
N->mergeWith(DSNodeHandle(this, Offset), NH.getOffset());
return;
}
+ // 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 = Offset-NH.getOffset();
+ unsigned NSize = N->getSize();
+
+ // Merge the type entries of the two nodes together...
+ if (N->Ty != Type::VoidTy) {
+ mergeTypeInfo(N->Ty, NOffset);
+
+ // 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;
+ NSize = N->getSize();
+ }
+ } else if (N->isNodeCompletelyFolded()) {
+ foldNodeCompletely();
+ if (hasNoReferrers()) return;
+ Offset = 0;
+ NOffset = NH.getOffset();
+ NSize = N->getSize();
+ }
+ N = NH.getNode();
+ if (this == N || N == 0) return;
+ assert((NodeType & DSNode::DEAD) == 0);
+
#if 0
std::cerr << "\n\nMerging:\n";
N->print(std::cerr, 0);
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(NSize+NOffset <= getSize() &&
- "Don't know how to merge extend a merged nodes size yet!");
-
// Remove all edges pointing at N, causing them to point to 'this' instead.
// Make sure to adjust their offset, not just the node pointer.
//
DSNodeHandle &Ref = *N->Referrers.back();
Ref = DSNodeHandle(this, NOffset+Ref.getOffset());
}
-
- // We must merge fields in this node due to nodes merged in the source node.
- // In order to handle this we build a map that converts from the source node's
- // MergeMap values to our MergeMap values. This map is indexed by the
- // expression: MergeMap[SMM+SourceNodeSize] so we need to allocate at least
- // 2*SourceNodeSize elements of space for the mapping. We can do this because
- // we know that there are at most SourceNodeSize outgoing links in the node
- // (thus that many positive values) and at most SourceNodeSize distinct fields
- // (thus that many negative values).
- //
- std::vector<signed char> MergeMapMap(NSize*2, 127);
-
- // Loop through the structures, merging them together...
- for (unsigned i = 0, e = NSize; i != e; ++i) {
- // Get what this byte of N maps to...
- signed char NElement = N->MergeMap[i];
-
- // Get what we map this byte to...
- signed char Element = MergeMap[i+NOffset];
- // We use 127 as a sentinal and don't check for it's existence yet...
- assert(Element != 127 && "MergeMapMap doesn't permit 127 values yet!");
-
- signed char CurMappedVal = MergeMapMap[NElement+NSize];
- if (CurMappedVal == 127) { // Haven't seen this NElement yet?
- MergeMapMap[NElement+NSize] = Element; // Map the two together...
- } else if (CurMappedVal != Element) {
- // If we are mapping two different fields together this means that we need
- // to merge fields in the current node due to merging in the source node.
- //
- mergeMappedValues(CurMappedVal, Element);
- MergeMapMap[NElement+NSize] = MergeMap[i+NOffset];
- }
- }
+ 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, e = NSize; i != e; ++i)
- if (DSNodeHandle *Link = N->getLink(i)) {
- addEdgeTo(i+NOffset, *Link);
- N->MergeMap[i] = -1; // Kill outgoing edge
+ 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; // Node is now dead
+ if (Size == 1)
+ break; // Node got collapsed
}
+ }
// Now that there are no outgoing edges, all of the Links are dead.
N->Links.clear();
+ N->Size = 0;
+ N->Ty = Type::VoidTy;
// Merge the node types
NodeType |= N->NodeType;
- N->NodeType = 0; // N is now a dead node.
-
- // If this merging into node has more than just void nodes in it, merge!
- assert(!N->TypeEntries.empty() && "TypeEntries is empty for a node?");
- if (N->TypeEntries.size() != 1 || N->TypeEntries[0].first != Type::VoidTy) {
- // If the current node just has a Void entry in it, remove it.
- if (TypeEntries.size() == 1 && TypeEntries[0].first == Type::VoidTy)
- TypeEntries.clear();
-
- // Adjust all of the type entries we are merging in by the offset... and add
- // them to the TypeEntries list.
- //
- if (NOffset != 0) { // This case is common enough to optimize for
- // Offset all of the TypeEntries in N with their new offset
- for (unsigned i = 0, e = N->TypeEntries.size(); i != e; ++i)
- N->TypeEntries[i].second += NOffset;
- }
-
- MergeSortedVectors(TypeEntries, N->TypeEntries);
-
- N->TypeEntries.clear();
- }
+ N->NodeType = DEAD; // N is now a dead node.
// Merge the globals list...
if (!N->Globals.empty()) {
}
}
+//===----------------------------------------------------------------------===//
+// DSCallSite Implementation
+//===----------------------------------------------------------------------===//
+
+// Define here to avoid including iOther.h and BasicBlock.h in DSGraph.h
+Function &DSCallSite::getCaller() const {
+ return *Inst->getParent()->getParent();
+}
+
+
//===----------------------------------------------------------------------===//
// DSGraph Implementation
//===----------------------------------------------------------------------===//
-DSGraph::DSGraph(const DSGraph &G) : Func(G.Func) {
- std::map<const DSNode*, DSNode*> NodeMap;
- RetNode = cloneInto(G, ValueMap, NodeMap);
+DSGraph::DSGraph(const DSGraph &G) : Func(G.Func), GlobalsGraph(0) {
+ PrintAuxCalls = false;
+ std::map<const DSNode*, DSNodeHandle> NodeMap;
+ RetNode = cloneInto(G, ScalarMap, NodeMap);
+}
+
+DSGraph::DSGraph(const DSGraph &G,
+ std::map<const DSNode*, DSNodeHandle> &NodeMap)
+ : Func(G.Func), GlobalsGraph(0) {
+ PrintAuxCalls = false;
+ RetNode = cloneInto(G, ScalarMap, NodeMap);
}
DSGraph::~DSGraph() {
FunctionCalls.clear();
- ValueMap.clear();
- RetNode = 0;
+ AuxFunctionCalls.clear();
+ ScalarMap.clear();
+ RetNode.setNode(0);
-#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>);
// dump - Allow inspection of graph in a debugger.
void DSGraph::dump() const { print(std::cerr); }
-// Helper function used to clone a function list.
-//
-static void CopyFunctionCallsList(const vector<vector<DSNodeHandle> >&fromCalls,
- vector<vector<DSNodeHandle> > &toCalls,
- std::map<const DSNode*, DSNode*> &NodeMap) {
-
- unsigned FC = toCalls.size(); // FirstCall
- toCalls.reserve(FC+fromCalls.size());
- for (unsigned i = 0, ei = fromCalls.size(); i != ei; ++i) {
- toCalls.push_back(vector<DSNodeHandle>());
-
- const vector<DSNodeHandle> &CurCall = fromCalls[i];
- toCalls.back().reserve(CurCall.size());
- for (unsigned j = 0, ej = fromCalls[i].size(); j != ej; ++j)
- toCalls[FC+i].push_back(DSNodeHandle(NodeMap[CurCall[j].getNode()],
- CurCall[j].getOffset()));
- }
-}
/// remapLinks - Change all of the Links in the current node according to the
/// specified mapping.
-void DSNode::remapLinks(std::map<const DSNode*, DSNode*> &OldNodeMap) {
- for (unsigned i = 0, e = Links.size(); i != e; ++i)
- Links[i].setNode(OldNodeMap[Links[i].getNode()]);
+///
+void DSNode::remapLinks(std::map<const DSNode*, DSNodeHandle> &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());
+ }
}
+
// cloneInto - Clone the specified DSGraph into the current graph, returning the
-// Return node of the graph. The translated ValueMap for the old function is
-// filled into the OldValMap member. If StripLocals is set to true, Scalar and
-// Alloca markers are removed from the graph, as the graph is being cloned into
-// a calling function's graph.
+// 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*, DSNode*> &OldNodeMap,
- bool StripScalars, bool StripAllocas,
- bool CopyCallers, bool CopyOrigCalls) {
+ std::map<const DSNode*, DSNodeHandle> &OldNodeMap,
+ unsigned CloneFlags) {
assert(OldNodeMap.empty() && "Returned OldNodeMap should be empty!");
+ assert(&G != this && "Cannot clone graph into itself!");
unsigned FN = Nodes.size(); // First new node...
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);
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 local markers as specified
- unsigned char StripBits = (StripScalars ? DSNode::ScalarNode : 0) |
- (StripAllocas ? DSNode::AllocaNode : 0);
- if (StripBits)
+ // Remove alloca markers as specified
+ if (CloneFlags & StripAllocaBit)
for (unsigned i = FN, e = Nodes.size(); i != e; ++i)
- Nodes[i]->NodeType &= ~StripBits;
-
- // Copy the value map...
- for (std::map<Value*, DSNodeHandle>::const_iterator I = G.ValueMap.begin(),
- E = G.ValueMap.end(); I != E; ++I)
- OldValMap[I->first] = DSNodeHandle(OldNodeMap[I->second.getNode()],
- I->second.getOffset());
- // Copy the function calls list...
- CopyFunctionCallsList(G.FunctionCalls, FunctionCalls, OldNodeMap);
+ Nodes[i]->NodeType &= ~DSNode::AllocaNode;
+
+ // Copy the value map... and merge all of the global nodes...
+ for (std::map<Value*, DSNodeHandle>::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());
+
+ 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 0
- if (CopyOrigCalls)
- CopyFunctionCallsList(G.OrigFunctionCalls, OrigFunctionCalls, OldNodeMap);
+ 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));
+ }
- // Copy the list of unresolved callers
- if (CopyCallers)
- PendingCallers.insert(G.PendingCallers.begin(), G.PendingCallers.end());
-#endif
+ if (!(CloneFlags & DontCloneAuxCallNodes)) {
+ // Copy the auxillary 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...
- return DSNodeHandle(OldNodeMap[G.RetNode.getNode()], G.RetNode.getOffset());
+ DSNodeHandle &MappedRet = OldNodeMap[G.RetNode.getNode()];
+ return DSNodeHandle(MappedRet.getNode(),
+ MappedRet.getOffset()+G.RetNode.getOffset());
+}
+
+/// 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;
+
+ // 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;
+
+ // 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();
+ }
+
+ // Merge the return value with the return value of the context...
+ RetVal.mergeWith(CS.getRetVal());
+
+ // 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;
+#ifndef NDEBUG
+ if (AI == F.aend())
+ std::cerr << "Bad call to Function: " << F.getName() << "\n";
+#endif
+ assert(AI != F.aend() && "# Args provided is not # Args required!");
+ }
+
+ // 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
if (GNode == 0 || GNode->getGlobals().size() == 0) return 0;
// If a clone has already been created for GNode, return it.
- DSNodeHandle& ValMapEntry = ValueMap[GNode->getGlobals()[0]];
+ DSNodeHandle& ValMapEntry = ScalarMap[GNode->getGlobals()[0]];
if (ValMapEntry != 0)
return ValMapEntry;
ValMapEntry = NewNode; // j=0 case of loop below!
Nodes.push_back(NewNode);
for (unsigned j = 1, N = NewNode->getGlobals().size(); j < N; ++j)
- ValueMap[NewNode->getGlobals()[j]] = NewNode;
+ 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)
N->NodeType |= DSNode::Incomplete;
// Recusively process children...
- for (unsigned i = 0, e = N->getSize(); i != e; ++i)
- if (DSNodeHandle *DSNH = N->getLink(i))
- markIncompleteNode(DSNH->getNode());
+ 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
// 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()) && ValueMap.find(I) != ValueMap.end()) {
- DSNodeHandle &INH = ValueMap[I];
- if (INH.getNode() && INH.hasLink(0))
- markIncompleteNode(ValueMap[I].getLink(0)->getNode());
- }
+ 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) {
- vector<DSNodeHandle> &Args = FunctionCalls[i];
- // Then the return value is certainly incomplete!
- markIncompleteNode(Args[0].getNode());
-
- // The call does not make the function argument incomplete...
-
- // All arguments to the function call are incomplete though!
- for (unsigned i = 2, e = Args.size(); i != e; ++i)
- markIncompleteNode(Args[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 or cast nodes as incomplete...
+ // 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];
- for (unsigned i = 0, e = N->getSize(); i != e; ++i)
- if (DSNodeHandle *DSNH = N->getLink(i))
- markIncompleteNode(DSNH->getNode());
+ for (unsigned i = 0, e = N->getSize(); i < e; i += DS::PointerSize)
+ if (DSNode *DSN = N->getLink(i).getNode())
+ markIncompleteNode(DSN);
}
}
// removeRefsToGlobal - Helper function that removes globals from the
-// ValueMap so that the referrer count will go down to zero.
+// ScalarMap so that the referrer count will go down to zero.
static void removeRefsToGlobal(DSNode* N,
- std::map<Value*, DSNodeHandle> &ValueMap) {
+ std::map<Value*, DSNodeHandle> &ScalarMap) {
while (!N->getGlobals().empty()) {
GlobalValue *GV = N->getGlobals().back();
N->getGlobals().pop_back();
- ValueMap.erase(GV);
+ ScalarMap.erase(GV);
}
}
// dead.
//
bool DSGraph::isNodeDead(DSNode *N) {
- // Is it a trivially dead shadow node...
- if (N->getReferrers().empty() && N->NodeType == 0)
- return true;
-
- // Is it a function node or some other trivially unused global?
- if (N->NodeType != 0 &&
- (N->NodeType & ~DSNode::GlobalNode) == 0 &&
- N->getSize() == 0 &&
- N->getReferrers().size() == N->getGlobals().size()) {
+ // Is it a trivially dead shadow node?
+ return N->getReferrers().empty() && (N->NodeType & ~DSNode::DEAD) == 0;
+}
- // Remove the globals from the valuemap, so that the referrer count will go
- // down to zero.
- removeRefsToGlobal(N, ValueMap);
- assert(N->getReferrers().empty() && "Referrers should all be gone now!");
- return true;
- }
+static inline void killIfUselessEdge(DSNodeHandle &Edge) {
+ if (DSNode *N = Edge.getNode()) // Is there an edge?
+ if (N->getReferrers().size() == 1) // Does it point to a lonely node?
+ if ((N->NodeType & ~DSNode::Incomplete) == 0 && // No interesting info?
+ N->getType() == Type::VoidTy && !N->isNodeCompletelyFolded())
+ Edge.setNode(0); // Kill the edge!
+}
+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<vector<DSNodeHandle> > &Calls,
+static void removeIdenticalCalls(vector<DSCallSite> &Calls,
const std::string &where) {
// Remove trivially identical function calls
unsigned NumFns = Calls.size();
- std::sort(Calls.begin(), 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;
+ 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.
+ killIfUselessEdge(CS.getCallee());
+ if (CS.getCallee().getNode() == 0) {
+ 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.getCallee().getNode() == LastCalleeNode) {
+ ++NumDuplicateCalls;
+ if (NumDuplicateCalls == 1) {
+ LastCalleeContainsExternalFunction =
+ nodeContainsExternalFunction(LastCalleeNode);
+ }
+
+ 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;
+ }
+ } else {
+ LastCalleeNode = CS.getCallee().getNode();
+ 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";);
}
+
// 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...
- }
-
+void DSGraph::removeTriviallyDeadNodes() {
removeIdenticalCalls(FunctionCalls, Func ? Func->getName() : "");
+ removeIdenticalCalls(AuxFunctionCalls, Func ? Func->getName() : "");
+
+ for (unsigned i = 0; i != Nodes.size(); ++i)
+ if (isNodeDead(Nodes[i])) { // This node is dead!
+ delete Nodes[i]; // Free memory...
+ Nodes.erase(Nodes.begin()+i--); // Remove from node list...
+ }
}
//
static void markAlive(DSNode *N, std::set<DSNode*> &Alive) {
if (N == 0) return;
+ std::set<DSNode*>::iterator I = Alive.lower_bound(N);
+ if (I != Alive.end() && *I == N) return; // Already marked alive
+ Alive.insert(I, N); // Is alive now
- Alive.insert(N);
- for (unsigned i = 0, e = N->getSize(); i != e; ++i)
- if (DSNodeHandle *DSNH = N->getLink(i))
- if (!Alive.count(DSNH->getNode()))
- markAlive(DSNH->getNode(), Alive);
+ for (unsigned i = 0, e = N->getSize(); i < e; i += DS::PointerSize)
+ markAlive(N->getLink(i).getNode(), Alive);
}
-static bool checkGlobalAlive(DSNode *N, std::set<DSNode*> &Alive,
- std::set<DSNode*> &Visiting) {
+// markAliveIfCanReachAlive - Simple graph walker that recursively traverses the
+// graph looking for a node that is marked alive. If the node is marked alive,
+// the recursive unwind marks node alive that can point to the alive node. This
+// is basically just a post-order traversal.
+//
+// This function returns true if the specified node is alive.
+//
+static bool markAliveIfCanReachAlive(DSNode *N, std::set<DSNode*> &Alive,
+ std::set<DSNode*> &Visited) {
if (N == 0) return false;
- if (Visiting.count(N)) return false; // terminate recursion on a cycle
- Visiting.insert(N);
-
- // If any immediate successor is alive, N is alive
- for (unsigned i = 0, e = N->getSize(); i != e; ++i)
- if (DSNodeHandle *DSNH = N->getLink(i))
- if (Alive.count(DSNH->getNode())) {
- Visiting.erase(N);
- return true;
- }
-
- // Else if any successor reaches a live node, N is alive
- for (unsigned i = 0, e = N->getSize(); i != e; ++i)
- if (DSNodeHandle *DSNH = N->getLink(i))
- if (checkGlobalAlive(DSNH->getNode(), Alive, Visiting)) {
- Visiting.erase(N); return true;
- }
+ // If we know that this node is alive, return so!
+ if (Alive.count(N)) return true;
- Visiting.erase(N);
- return false;
-}
+ // Otherwise, we don't think the node is alive yet, check for infinite
+ // recursion.
+ std::set<DSNode*>::iterator VI = Visited.lower_bound(N);
+ if (VI != Visited.end() && *VI == N) return false; // Found a cycle
+ // No recursion, insert into Visited...
+ Visited.insert(VI, N);
+ if (N->NodeType & DSNode::GlobalNode)
+ return false; // Global nodes will be marked on their own
-// 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<vector<DSNodeHandle> > &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);
- }
- }
+ bool ChildrenAreAlive = false;
- // 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 (int i = 0, ei = Calls.size(); i < ei; ++i) {
- bool CallIsDead = true, CallHasDeadArg = false;
- for (unsigned j = 0, ej = Calls[i].size(); j != ej; ++j) {
- bool argIsDead = Calls[i][j].getNode() == 0 ||
- Alive.count(Calls[i][j].getNode()) == 0;
- CallHasDeadArg |= (Calls[i][j].getNode() != 0 && argIsDead);
- CallIsDead &= argIsDead;
- }
- 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 = Calls[i].size(); j != ej; ++j)
- markAlive(Calls[i][j].getNode(), Alive);
- }
- }
- if (recurse)
- markGlobalsIteration(GlobalNodes, Calls, Alive, FilterCalls);
- }
+ for (unsigned i = 0, e = N->getSize(); i < e; i += DS::PointerSize)
+ ChildrenAreAlive |= markAliveIfCanReachAlive(N->getLink(i).getNode(),
+ Alive, Visited);
+ if (ChildrenAreAlive)
+ markAlive(N, Alive);
+ return ChildrenAreAlive;
}
+static bool CallSiteUsesAliveArgs(DSCallSite &CS, std::set<DSNode*> &Alive,
+ std::set<DSNode*> &Visited) {
+ if (markAliveIfCanReachAlive(CS.getRetVal().getNode(), Alive, Visited) ||
+ markAliveIfCanReachAlive(CS.getCallee().getNode(), Alive, Visited))
+ return true;
+ for (unsigned j = 0, e = CS.getNumPtrArgs(); j != e; ++j)
+ if (markAliveIfCanReachAlive(CS.getPtrArg(j).getNode(), Alive, Visited))
+ return true;
+ return false;
+}
-// 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<vector<DSNodeHandle> > &Calls = G.getFunctionCalls();
- if (FilterCalls) {
- for (unsigned i = 0, e = Calls.size(); i != e; ++i)
- for (unsigned j = 0, e = Calls[i].size(); j != e; ++j)
- if (Calls[i][j].getNode())
- GlobalNodes.insert(Calls[i][j].getNode());
- }
-
- // 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 ValueMap
- std::set<DSNode*>::iterator I=GlobalNodes.begin(), E=GlobalNodes.end();
- for( ; I != E; ++I)
- if (Alive.count(*I) == 0)
- removeRefsToGlobal(*I, G.getValueMap());
-
- // 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].size(); CallIsDead && j != ej; ++j)
- CallIsDead = Alive.count(Calls[i][j].getNode()) == 0;
- if (CallIsDead)
- Calls.erase(Calls.begin() + i); // remove the call entirely
- }
+static void markAlive(DSCallSite &CS, std::set<DSNode*> &Alive) {
+ markAlive(CS.getRetVal().getNode(), Alive);
+ markAlive(CS.getCallee().getNode(), Alive);
+
+ for (unsigned j = 0, e = CS.getNumPtrArgs(); j != e; ++j)
+ markAlive(CS.getPtrArg(j).getNode(), Alive);
}
// 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) &&
- "KeepAllGlobals without KeepCalls is meaningless");
-
+void DSGraph::removeDeadNodes() {
// Reduce the amount of work we have to do...
- removeTriviallyDeadNodes(KeepAllGlobals);
+ removeTriviallyDeadNodes();
// FIXME: Merge nontrivially identical call nodes...
// Alive - a set that holds all nodes found to be reachable/alive.
std::set<DSNode*> Alive;
+ std::vector<std::pair<Value*, DSNode*> > GlobalNodes;
- // 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].size(); j != e; ++j)
- markAlive(FunctionCalls[i][j].getNode(), Alive);
-
-#if 0
- for (unsigned i = 0, e = OrigFunctionCalls.size(); i != e; ++i)
- for (unsigned j = 0, e = OrigFunctionCalls[i].size(); j != e; ++j)
- markAlive(OrigFunctionCalls[i][j].getNode(), Alive);
-#endif
-
- // Mark all nodes reachable by scalar nodes (and global nodes, if
- // keeping them was specified) as alive...
- unsigned char keepBits = DSNode::ScalarNode |
- (KeepAllGlobals ? DSNode::GlobalNode : 0);
- for (unsigned i = 0, e = Nodes.size(); i != e; ++i)
- if (Nodes[i]->NodeType & keepBits)
- markAlive(Nodes[i], Alive);
+ // Mark all nodes reachable by (non-global) scalar nodes as alive...
+ for (std::map<Value*, DSNodeHandle>::iterator I = ScalarMap.begin(),
+ E = ScalarMap.end(); I != E; ++I)
+ if (!isa<GlobalValue>(I->first)) // Don't mark globals!
+ markAlive(I->second.getNode(), Alive);
+ else // Keep track of global nodes
+ GlobalNodes.push_back(std::make_pair(I->first, I->second.getNode()));
// 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.
- if (! KeepAllGlobals)
- markGlobalsAlive(*this, Alive, ! KeepCalls);
+ // If any global nodes points to a non-global that is "alive", the global is
+ // "alive" as well...
+ //
+ std::set<DSNode*> Visited;
+ for (unsigned i = 0, e = GlobalNodes.size(); i != e; ++i)
+ markAliveIfCanReachAlive(GlobalNodes[i].second, Alive, Visited);
+
+ std::vector<bool> FCallsAlive(FunctionCalls.size());
+ for (unsigned i = 0, e = FunctionCalls.size(); i != e; ++i)
+ if (CallSiteUsesAliveArgs(FunctionCalls[i], Alive, Visited)) {
+ markAlive(FunctionCalls[i], Alive);
+ FCallsAlive[i] = true;
+ }
+
+ std::vector<bool> AuxFCallsAlive(AuxFunctionCalls.size());
+ for (unsigned i = 0, e = AuxFunctionCalls.size(); i != e; ++i)
+ if (CallSiteUsesAliveArgs(AuxFunctionCalls[i], Alive, Visited)) {
+ markAlive(AuxFunctionCalls[i], Alive);
+ AuxFCallsAlive[i] = true;
+ }
+
+ // Remove all dead function calls...
+ unsigned CurIdx = 0;
+ for (unsigned i = 0, e = FunctionCalls.size(); i != e; ++i)
+ if (FCallsAlive[i])
+ FunctionCalls[CurIdx++].swap(FunctionCalls[i]);
+ // Crop all the bad ones out...
+ FunctionCalls.erase(FunctionCalls.begin()+CurIdx, FunctionCalls.end());
+
+ // Remove all dead aux function calls...
+ CurIdx = 0;
+ for (unsigned i = 0, e = AuxFunctionCalls.size(); i != e; ++i)
+ if (AuxFCallsAlive[i])
+ AuxFunctionCalls[CurIdx++].swap(AuxFunctionCalls[i]);
+ // Crop all the bad ones out...
+ AuxFunctionCalls.erase(AuxFunctionCalls.begin()+CurIdx,
+ AuxFunctionCalls.end());
+
+
+ // Remove all unreachable globals from the ScalarMap
+ for (unsigned i = 0, e = GlobalNodes.size(); i != e; ++i)
+ if (!Alive.count(GlobalNodes[i].second))
+ ScalarMap.erase(GlobalNodes[i].first);
// Loop over all unreachable nodes, dropping their references...
vector<DSNode*> DeadNodes;
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");
-}
-
-void GlobalDSGraph::addReference(const DSGraph* referrer) {
- if (referrer != this)
- Referrers.insert(referrer);
-}
-
-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;
- }
-}
-
+#if 0
// Bits used in the next function
-static const char ExternalTypeBits = DSNode::GlobalNode | DSNode::NewNode;
+static const char ExternalTypeBits = DSNode::GlobalNode | DSNode::HeapNode;
+
-#if 0
// 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,
// 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 = ValueMap[OldNode->getGlobals()[j]].getNode()) {
+ if (DSNode *PrevNode = ScalarMap[OldNode->getGlobals()[j]].getNode()) {
if (NewNode == 0) {
NewNode = PrevNode; // first existing node found
if (GlobalsAreFinal && j == 0)
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)
- ValueMap[PrevNode->getGlobals()[k]] = NewNode;
+ ScalarMap[PrevNode->getGlobals()[k]] = NewNode;
NewNode->mergeWith(PrevNode);
}
} else if (NewNode != 0) {
- ValueMap[OldNode->getGlobals()[j]] = NewNode; // add the merged node
+ ScalarMap[OldNode->getGlobals()[j]] = NewNode; // add the merged node
}
// If no existing node was found, clone the node and update the ValMap.
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)
- ValueMap[NewNode->getGlobals()[j]] = NewNode;
+ ScalarMap[NewNode->getGlobals()[j]] = NewNode;
}
else
NewNode->NodeType |= OldNode->NodeType; // Markers may be different!
}
-// 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
-}
-
-
// 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<vector<DSNodeHandle> >& FromCalls =Graph.FunctionCalls;
+ vector<DSCallSite >& FromCalls =Graph.FunctionCalls;
FunctionCalls.reserve(FunctionCalls.size() + FromCalls.size());
for (int i = 0, ei = FromCalls.size(); i < ei; ++i) {
- FunctionCalls.push_back(vector<DSNodeHandle>());
- FunctionCalls.back().reserve(FromCalls[i].size());
+ DSCallSite& callCopy = FunctionCalls.back();
+ callCopy.reserve(FromCalls[i].size());
for (unsigned j = 0, ej = FromCalls[i].size(); j != ej; ++j)
- FunctionCalls.back().push_back
+ callCopy.push_back
((FromCalls[i][j] && (FromCalls[i][j]->NodeType & ExternalTypeBits))
? cloneNodeInto(FromCalls[i][j], NodeCache, true)
: 0);
projects / oota-llvm.git / blobdiff