Add the ability to "intern" FoldingSetNodeID data into a
BumpPtrAllocator-allocated region to allow it to be stored in a more
compact form and to avoid the need for a non-trivial destructor call.
Use this new mechanism in ScalarEvolution instead of
FastFoldingSetNode to avoid leaking memory in the case where a
FoldingSetNodeID uses heap storage, and to reduce overall memory
usage.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@98829 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Support/FoldingSet.cpp b/lib/Support/FoldingSet.cpp
index 954dc77..3f467fe 100644
--- a/lib/Support/FoldingSet.cpp
+++ b/lib/Support/FoldingSet.cpp
@@ -15,6 +15,7 @@
//===----------------------------------------------------------------------===//
#include "llvm/ADT/FoldingSet.h"
+#include "llvm/Support/Allocator.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/MathExtras.h"
#include <cassert>
@@ -130,6 +131,15 @@
return memcmp(&Bits[0], &RHS.Bits[0], Bits.size()*sizeof(Bits[0])) == 0;
}
+/// Intern - Copy this node's data to a memory region allocated from the
+/// given allocator and return a FoldingSetNodeIDRef describing the
+/// interned data.
+FoldingSetNodeIDRef
+FoldingSetNodeID::Intern(BumpPtrAllocator &Allocator) const {
+ unsigned *New = Allocator.Allocate<unsigned>(Bits.size());
+ std::uninitialized_copy(Bits.begin(), Bits.end(), New);
+ return FoldingSetNodeIDRef(New, Bits.size());
+}
//===----------------------------------------------------------------------===//
/// Helper functions for FoldingSetImpl.