Vendor import of llvm trunk r126079:

http://llvm.org/svn/llvm-project/llvm/trunk@126079

1 files changed, 8 insertions, 2 deletions

diff --git a/lib/Support/Allocator.cpp b/lib/Support/Allocator.cpp
index 90df262..5e27df6 100644
--- a/lib/Support/Allocator.cpp
+++ b/lib/Support/Allocator.cpp
@@ -12,10 +12,10 @@
 //===----------------------------------------------------------------------===//
 
 #include "llvm/Support/Allocator.h"
-#include "llvm/System/DataTypes.h"
+#include "llvm/Support/DataTypes.h"
 #include "llvm/Support/Recycler.h"
 #include "llvm/Support/raw_ostream.h"
-#include "llvm/System/Memory.h"
+#include "llvm/Support/Memory.h"
 #include <cstring>
 
 namespace llvm {
@@ -44,6 +44,12 @@ char *BumpPtrAllocator::AlignPtr(char *Ptr, size_t Alignment) {
 /// StartNewSlab - Allocate a new slab and move the bump pointers over into
 /// the new slab.  Modifies CurPtr and End.
 void BumpPtrAllocator::StartNewSlab() {
+  // If we allocated a big number of slabs already it's likely that we're going
+  // to allocate more. Increase slab size to reduce mallocs and possibly memory
+  // overhead. The factors are chosen conservatively to avoid overallocation.
+  if (BytesAllocated >= SlabSize * 128)
+    SlabSize *= 2;
+
   MemSlab *NewSlab = Allocator.Allocate(SlabSize);
   NewSlab->NextPtr = CurSlab;
   CurSlab = NewSlab;