Substantially improve the DSA code by removing 'forwarding' nodes from
DSGraphs while they are forwarding. When the last reference to the forwarding
node is dropped, the forwarding node is autodeleted. This should simplify
removeTriviallyDead nodes, and is only (efficiently) possible because we are
using an ilist of dsnodes now.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@11175 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/include/llvm/Analysis/DSGraph.h b/include/llvm/Analysis/DSGraph.h
index 568a90b..1c10851 100644
--- a/include/llvm/Analysis/DSGraph.h
+++ b/include/llvm/Analysis/DSGraph.h
@@ -182,6 +182,7 @@
/// addNode - Add a new node to the graph.
///
void addNode(DSNode *N) { Nodes.push_back(N); }
+ void unlinkNode(DSNode *N) { Nodes.remove(N); }
/// getScalarMap - Get a map that describes what the nodes the scalars in this
/// function point to...
diff --git a/include/llvm/Analysis/DSNode.h b/include/llvm/Analysis/DSNode.h
index e76a480..6112931 100644
--- a/include/llvm/Analysis/DSNode.h
+++ b/include/llvm/Analysis/DSNode.h
@@ -159,12 +159,18 @@
DSNode *getForwardNode() const { return ForwardNH.getNode(); }
/// isForwarding - Return true if this node is forwarding to another.
+ ///
bool isForwarding() const { return !ForwardNH.isNull(); }
+ /// stopForwarding - When the last reference to this forwarding node has been
+ /// dropped, delete the node.
void stopForwarding() {
assert(isForwarding() &&
"Node isn't forwarding, cannot stopForwarding!");
ForwardNH.setNode(0);
+ assert(ParentGraph == 0 &&
+ "Forwarding nodes must have been removed from graph!");
+ delete this;
}
/// hasLink - Return true if this memory object has a link in slot #LinkNo
@@ -377,8 +383,8 @@
}
inline void DSNodeHandle::setNode(DSNode *n) const {
- assert(!n || !n->getForwardNode() && "Cannot set node to a forwarded node!");
- if (N) N->NumReferrers--;
+ assert(!n || !n->isForwarding() && "Cannot set node to a forwarded node!");
+ if (N) getNode()->NumReferrers--;
N = n;
if (N) {
N->NumReferrers++;
diff --git a/include/llvm/Analysis/DataStructure/DSGraph.h b/include/llvm/Analysis/DataStructure/DSGraph.h
index 568a90b..1c10851 100644
--- a/include/llvm/Analysis/DataStructure/DSGraph.h
+++ b/include/llvm/Analysis/DataStructure/DSGraph.h
@@ -182,6 +182,7 @@
/// addNode - Add a new node to the graph.
///
void addNode(DSNode *N) { Nodes.push_back(N); }
+ void unlinkNode(DSNode *N) { Nodes.remove(N); }
/// getScalarMap - Get a map that describes what the nodes the scalars in this
/// function point to...
diff --git a/include/llvm/Analysis/DataStructure/DSNode.h b/include/llvm/Analysis/DataStructure/DSNode.h
index e76a480..6112931 100644
--- a/include/llvm/Analysis/DataStructure/DSNode.h
+++ b/include/llvm/Analysis/DataStructure/DSNode.h
@@ -159,12 +159,18 @@
DSNode *getForwardNode() const { return ForwardNH.getNode(); }
/// isForwarding - Return true if this node is forwarding to another.
+ ///
bool isForwarding() const { return !ForwardNH.isNull(); }
+ /// stopForwarding - When the last reference to this forwarding node has been
+ /// dropped, delete the node.
void stopForwarding() {
assert(isForwarding() &&
"Node isn't forwarding, cannot stopForwarding!");
ForwardNH.setNode(0);
+ assert(ParentGraph == 0 &&
+ "Forwarding nodes must have been removed from graph!");
+ delete this;
}
/// hasLink - Return true if this memory object has a link in slot #LinkNo
@@ -377,8 +383,8 @@
}
inline void DSNodeHandle::setNode(DSNode *n) const {
- assert(!n || !n->getForwardNode() && "Cannot set node to a forwarded node!");
- if (N) N->NumReferrers--;
+ assert(!n || !n->isForwarding() && "Cannot set node to a forwarded node!");
+ if (N) getNode()->NumReferrers--;
N = n;
if (N) {
N->NumReferrers++;
diff --git a/lib/Analysis/DataStructure/DataStructure.cpp b/lib/Analysis/DataStructure/DataStructure.cpp
index 57651d7..68530f0 100644
--- a/lib/Analysis/DataStructure/DataStructure.cpp
+++ b/lib/Analysis/DataStructure/DataStructure.cpp
@@ -46,7 +46,7 @@
using namespace DS;
DSNode *DSNodeHandle::HandleForwarding() const {
- assert(!N->ForwardNH.isNull() && "Can only be invoked if forwarding!");
+ assert(N->isForwarding() && "Can only be invoked if forwarding!");
// Handle node forwarding here!
DSNode *Next = N->ForwardNH.getNode(); // Cause recursive shrinkage
@@ -124,6 +124,10 @@
NodeType = DEAD;
Size = 0;
Ty = Type::VoidTy;
+
+ // Remove this node from the parent graph's Nodes list.
+ ParentGraph->unlinkNode(this);
+ ParentGraph = 0;
}
// addGlobal - Add an entry for a global value to the Globals list. This also