[cfe-commits] r173512 - in /cfe/trunk: include/clang/Serialization/ModuleManager.h lib/Serialization/ModuleManager.cpp
Douglas Gregor
dgregor at apple.com
Fri Jan 25 14:28:56 PST 2013
Author: dgregor
Date: Fri Jan 25 16:25:23 2013
New Revision: 173512
URL: http://llvm.org/viewvc/llvm-project?rev=173512&view=rev
Log:
Optimize ModuleManager::visit() by precomputing the visitation order
and limiting ourselves to two memory allocations. 10% speedup in
-fsyntax-only time for modules.
With this change, we can actually see some performance different from
the global module index, but it's still about 1%.
Modified:
cfe/trunk/include/clang/Serialization/ModuleManager.h
cfe/trunk/lib/Serialization/ModuleManager.cpp
Modified: cfe/trunk/include/clang/Serialization/ModuleManager.h
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/include/clang/Serialization/ModuleManager.h?rev=173512&r1=173511&r2=173512&view=diff
==============================================================================
--- cfe/trunk/include/clang/Serialization/ModuleManager.h (original)
+++ cfe/trunk/include/clang/Serialization/ModuleManager.h Fri Jan 25 16:25:23 2013
@@ -38,7 +38,10 @@ class ModuleManager {
/// \brief A lookup of in-memory (virtual file) buffers
llvm::DenseMap<const FileEntry *, llvm::MemoryBuffer *> InMemoryBuffers;
-
+
+ /// \brief The visitation order.
+ SmallVector<ModuleFile *, 4> VisitOrder;
+
public:
typedef SmallVector<ModuleFile*, 2>::iterator ModuleIterator;
typedef SmallVector<ModuleFile*, 2>::const_iterator ModuleConstIterator;
Modified: cfe/trunk/lib/Serialization/ModuleManager.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Serialization/ModuleManager.cpp?rev=173512&r1=173511&r2=173512&view=diff
==============================================================================
--- cfe/trunk/lib/Serialization/ModuleManager.cpp (original)
+++ cfe/trunk/lib/Serialization/ModuleManager.cpp Fri Jan 25 16:25:23 2013
@@ -149,77 +149,94 @@ ModuleManager::~ModuleManager() {
void ModuleManager::visit(bool (*Visitor)(ModuleFile &M, void *UserData),
void *UserData) {
- unsigned N = size();
-
- // Record the number of incoming edges for each module. When we
- // encounter a module with no incoming edges, push it into the queue
- // to seed the queue.
- SmallVector<ModuleFile *, 4> Queue;
- Queue.reserve(N);
- llvm::SmallVector<unsigned, 4> UnusedIncomingEdges;
- UnusedIncomingEdges.reserve(size());
- for (ModuleIterator M = begin(), MEnd = end(); M != MEnd; ++M) {
- if (unsigned Size = (*M)->ImportedBy.size())
- UnusedIncomingEdges.push_back(Size);
- else {
- UnusedIncomingEdges.push_back(0);
- Queue.push_back(*M);
+ // If the visitation number array is the wrong size, resize it and recompute
+ // an order.
+ if (VisitOrder.size() != Chain.size()) {
+ unsigned N = size();
+ VisitOrder.clear();
+ VisitOrder.reserve(N);
+
+ // Record the number of incoming edges for each module. When we
+ // encounter a module with no incoming edges, push it into the queue
+ // to seed the queue.
+ SmallVector<ModuleFile *, 4> Queue;
+ Queue.reserve(N);
+ llvm::SmallVector<unsigned, 4> UnusedIncomingEdges;
+ UnusedIncomingEdges.reserve(size());
+ for (ModuleIterator M = begin(), MEnd = end(); M != MEnd; ++M) {
+ if (unsigned Size = (*M)->ImportedBy.size())
+ UnusedIncomingEdges.push_back(Size);
+ else {
+ UnusedIncomingEdges.push_back(0);
+ Queue.push_back(*M);
+ }
+ }
+
+ // Traverse the graph, making sure to visit a module before visiting any
+ // of its dependencies.
+ unsigned QueueStart = 0;
+ while (QueueStart < Queue.size()) {
+ ModuleFile *CurrentModule = Queue[QueueStart++];
+ VisitOrder.push_back(CurrentModule);
+
+ // For any module that this module depends on, push it on the
+ // stack (if it hasn't already been marked as visited).
+ for (llvm::SetVector<ModuleFile *>::iterator
+ M = CurrentModule->Imports.begin(),
+ MEnd = CurrentModule->Imports.end();
+ M != MEnd; ++M) {
+ // Remove our current module as an impediment to visiting the
+ // module we depend on. If we were the last unvisited module
+ // that depends on this particular module, push it into the
+ // queue to be visited.
+ unsigned &NumUnusedEdges = UnusedIncomingEdges[(*M)->Index];
+ if (NumUnusedEdges && (--NumUnusedEdges == 0))
+ Queue.push_back(*M);
+ }
}
+
+ assert(VisitOrder.size() == N && "Visitation order is wrong?");
}
- llvm::SmallVector<bool, 4> Skipped(size(), false);
- unsigned QueueStart = 0;
- while (QueueStart < Queue.size()) {
- ModuleFile *CurrentModule = Queue[QueueStart++];
-
- // Check whether this module should be skipped.
- if (Skipped[CurrentModule->Index])
+ SmallVector<ModuleFile *, 4> Stack;
+ SmallVector<bool, 4> Visited(size(), false);
+
+ for (unsigned I = 0, N = VisitOrder.size(); I != N; ++I) {
+ ModuleFile *CurrentModule = VisitOrder[I];
+ // Should we skip this module file?
+ if (Visited[CurrentModule->Index])
continue;
- Skipped[CurrentModule->Index] = true;
-
- if (Visitor(*CurrentModule, UserData)) {
- // The visitor has requested that cut off visitation of any
- // module that the current module depends on. To indicate this
- // behavior, we mark all of the reachable modules as "skipped".
- SmallVector<ModuleFile *, 4> Stack;
- Stack.push_back(CurrentModule);
- Skipped[CurrentModule->Index] = true;
- while (!Stack.empty()) {
- ModuleFile *NextModule = Stack.back();
- Stack.pop_back();
-
- // For any module that this module depends on, push it on the
- // stack (if it hasn't already been marked as visited).
- for (llvm::SetVector<ModuleFile *>::iterator
- M = NextModule->Imports.begin(),
- MEnd = NextModule->Imports.end();
- M != MEnd; ++M) {
- if (!Skipped[(*M)->Index]) {
- Stack.push_back(*M);
- Skipped[(*M)->Index] = true;
- }
+
+ // Visit the module.
+ Visited[CurrentModule->Index] = true;
+ if (!Visitor(*CurrentModule, UserData))
+ continue;
+
+ // The visitor has requested that cut off visitation of any
+ // module that the current module depends on. To indicate this
+ // behavior, we mark all of the reachable modules as having been visited.
+ ModuleFile *NextModule = CurrentModule;
+ Stack.reserve(size());
+ do {
+ // For any module that this module depends on, push it on the
+ // stack (if it hasn't already been marked as visited).
+ for (llvm::SetVector<ModuleFile *>::iterator
+ M = NextModule->Imports.begin(),
+ MEnd = NextModule->Imports.end();
+ M != MEnd; ++M) {
+ if (!Visited[(*M)->Index]) {
+ Stack.push_back(*M);
+ Visited[(*M)->Index] = true;
}
}
- continue;
- }
-
- // For any module that this module depends on, push it on the
- // stack (if it hasn't already been marked as visited).
- for (llvm::SetVector<ModuleFile *>::iterator
- M = CurrentModule->Imports.begin(),
- MEnd = CurrentModule->Imports.end();
- M != MEnd; ++M) {
- if (Skipped[(*M)->Index])
- continue;
-
- // Remove our current module as an impediment to visiting the
- // module we depend on. If we were the last unvisited module
- // that depends on this particular module, push it into the
- // queue to be visited.
- unsigned &NumUnusedEdges = UnusedIncomingEdges[(*M)->Index];
- if (NumUnusedEdges && (--NumUnusedEdges == 0))
- Queue.push_back(*M);
- }
+
+ if (Stack.empty())
+ break;
+
+ // Pop the next module off the stack.
+ NextModule = Stack.back();
+ Stack.pop_back();
+ } while (true);
}
}
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