Teach selectiondag how to handle the stackprotectorcheck intrinsic.

[oota-llvm.git] / lib / Support / Allocator.cpp

diff --git a/lib/Support/Allocator.cpp b/lib/Support/Allocator.cpp
index 8bb07405ec60f9378e40a5b3806c205336627084..3c4191b805a368eecb820cdecb11dad839ae497a 100644 (file)
--- a/lib/Support/Allocator.cpp
+++ b/lib/Support/Allocator.cpp
@@ -12,18 +12,19 @@
 //===----------------------------------------------------------------------===//
 
 #include "llvm/Support/Allocator.h"
+#include "llvm/Support/Compiler.h"
 #include "llvm/Support/DataTypes.h"
+#include "llvm/Support/Memory.h"
 #include "llvm/Support/Recycler.h"
 #include "llvm/Support/raw_ostream.h"
-#include "llvm/Support/Memory.h"
 #include <cstring>
 
 namespace llvm {
 
 BumpPtrAllocator::BumpPtrAllocator(size_t size, size_t threshold,
                                    SlabAllocator &allocator)
-    : SlabSize(size), SizeThreshold(threshold), Allocator(allocator),
-      CurSlab(0), BytesAllocated(0) { }
+    : SlabSize(size), SizeThreshold(std::min(size, threshold)),
+      Allocator(allocator), CurSlab(0), BytesAllocated(0) { }
 
 BumpPtrAllocator::~BumpPtrAllocator() {
   DeallocateSlabs(CurSlab);
@@ -82,36 +83,36 @@ void BumpPtrAllocator::Reset() {
   CurSlab->NextPtr = 0;
   CurPtr = (char*)(CurSlab + 1);
   End = ((char*)CurSlab) + CurSlab->Size;
+  BytesAllocated = 0;
 }
 
 /// Allocate - Allocate space at the specified alignment.
 ///
 void *BumpPtrAllocator::Allocate(size_t Size, size_t Alignment) {
-  // 0-byte alignment means 1-byte alignment.
-  if (Alignment == 0) Alignment = 1;
-
-  size_t PaddedSize = Size + sizeof(MemSlab) + Alignment - 1;
-
-  // If requested size exceeds slab size, increase slab size.
-  while (PaddedSize > SlabSize)
-    SlabSize *= 2;
-
   if (!CurSlab) // Start a new slab if we haven't allocated one already.
     StartNewSlab();
 
   // Keep track of how many bytes we've allocated.
   BytesAllocated += Size;
 
+  // 0-byte alignment means 1-byte alignment.
+  if (Alignment == 0) Alignment = 1;
+
   // Allocate the aligned space, going forwards from CurPtr.
   char *Ptr = AlignPtr(CurPtr, Alignment);
 
   // Check if we can hold it.
   if (Ptr + Size <= End) {
     CurPtr = Ptr + Size;
+    // Update the allocation point of this memory block in MemorySanitizer.
+    // Without this, MemorySanitizer messages for values originated from here
+    // will point to the allocation of the entire slab.
+    __msan_allocated_memory(Ptr, Size);
     return Ptr;
   }
 
   // If Size is really big, allocate a separate slab for it.
+  size_t PaddedSize = Size + sizeof(MemSlab) + Alignment - 1;
   if (PaddedSize > SizeThreshold) {
     MemSlab *NewSlab = Allocator.Allocate(PaddedSize);
 
@@ -122,6 +123,7 @@ void *BumpPtrAllocator::Allocate(size_t Size, size_t Alignment) {
 
     Ptr = AlignPtr((char*)(NewSlab + 1), Alignment);
     assert((uintptr_t)Ptr + Size <= (uintptr_t)NewSlab + NewSlab->Size);
+    __msan_allocated_memory(Ptr, Size);
     return Ptr;
   }
 
@@ -130,6 +132,7 @@ void *BumpPtrAllocator::Allocate(size_t Size, size_t Alignment) {
   Ptr = AlignPtr(CurPtr, Alignment);
   CurPtr = Ptr + Size;
   assert(CurPtr <= End && "Unable to allocate memory!");
+  __msan_allocated_memory(Ptr, Size);
   return Ptr;
 }