RPCS3/llvm
1
0
Fork 0
mirror of https://github.com/RPCS3/llvm.git synced 2024-12-25 05:25:53 +00:00
Code Issues Actions Packages Projects Releases Wiki Activity

[LCG] Rather than removing nodes from the SCC entry set when we process

Browse Source 
them, just skip over any DFS-numbered nodes when finding the next root
of a DFS. This allows the entry set to just be a vector as we populate
it from a uniqued source. It also removes the possibility for a linear
scan of the entry set to actually do the removal which can make things
go quadratic if we get unlucky.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@207312 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Chandler Carruth 2014-04-26 09:45:55 +00:00
parent 797bbced53
commit 9a1fab37c7
2 changed files with 8 additions and 7 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
include/llvm/Analysis/LazyCallGraph.h
View File

@ -384,7 +384,7 @@ private:
SmallVector<std::pair<Node *, iterator>, 4> DFSStack; SmallVector<std::pair<Node *, iterator>, 4> DFSStack;
/// \brief Set of entry nodes not-yet-processed into SCCs. /// \brief Set of entry nodes not-yet-processed into SCCs.
SmallSetVector<Function *, 4> SCCEntryNodes; SmallVector<Function *, 4> SCCEntryNodes;
/// \brief Stack of nodes the DFS has walked but not yet put into a SCC. /// \brief Stack of nodes the DFS has walked but not yet put into a SCC.
SmallVector<Node *, 4> PendingSCCStack; SmallVector<Node *, 4> PendingSCCStack;

13
lib/Analysis/LazyCallGraph.cpp
View File

@ -100,9 +100,9 @@ LazyCallGraph::LazyCallGraph(Module &M) : NextDFSNumber(0) {
for (auto &Entry : EntryNodes) for (auto &Entry : EntryNodes)
if (Function *F = Entry.dyn_cast<Function *>()) if (Function *F = Entry.dyn_cast<Function *>())
SCCEntryNodes.insert(F); SCCEntryNodes.push_back(F);
else else
SCCEntryNodes.insert(&Entry.get<Node *>()->getFunction()); SCCEntryNodes.push_back(&Entry.get<Node *>()->getFunction());
} }
LazyCallGraph::LazyCallGraph(LazyCallGraph &&G) LazyCallGraph::LazyCallGraph(LazyCallGraph &&G)
@ -437,10 +437,12 @@ LazyCallGraph::SCC *LazyCallGraph::getNextSCCInPostOrder() {
DFSStack.pop_back(); DFSStack.pop_back();
} else { } else {
// If we've handled all candidate entry nodes to the SCC forest, we're done. // If we've handled all candidate entry nodes to the SCC forest, we're done.
if (SCCEntryNodes.empty()) do {
return nullptr; if (SCCEntryNodes.empty())
return nullptr;
N = &get(*SCCEntryNodes.pop_back_val()); N = &get(*SCCEntryNodes.pop_back_val());
} while (N->DFSNumber != 0);
I = N->begin(); I = N->begin();
N->LowLink = N->DFSNumber = 1; N->LowLink = N->DFSNumber = 1;
NextDFSNumber = 2; NextDFSNumber = 2;
@ -463,7 +465,6 @@ LazyCallGraph::SCC *LazyCallGraph::getNextSCCInPostOrder() {
assert(!SCCMap.count(&ChildN) && assert(!SCCMap.count(&ChildN) &&
"Found a node with 0 DFS number but already in an SCC!"); "Found a node with 0 DFS number but already in an SCC!");
ChildN.LowLink = ChildN.DFSNumber = NextDFSNumber++; ChildN.LowLink = ChildN.DFSNumber = NextDFSNumber++;
SCCEntryNodes.remove(&ChildN.getFunction());
N = &ChildN; N = &ChildN;
I = ChildN.begin(); I = ChildN.begin();
E = ChildN.end(); E = ChildN.end();