Add an AllocateRW to match AllocateRWX.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@48676 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 23 insertions, 0 deletions

diff --git a/lib/System/Win32/Memory.inc b/lib/System/Win32/Memory.inc
index eed2b100e6..12627521a3 100644
--- a/lib/System/Win32/Memory.inc
+++ b/lib/System/Win32/Memory.inc
@@ -46,6 +46,29 @@ MemoryBlock Memory::AllocateRWX(unsigned NumBytes,
   return result;
 }
 
+MemoryBlock Memory::AllocateRW(unsigned NumBytes,
+                                const MemoryBlock *NearBlock,
+                                std::string *ErrMsg) {
+  if (NumBytes == 0) return MemoryBlock();
+
+  static const long pageSize = Process::GetPageSize();
+  unsigned NumPages = (NumBytes+pageSize-1)/pageSize;
+
+  //FIXME: support NearBlock if ever needed on Win64.
+
+  void *pa = VirtualAlloc(NULL, NumPages*pageSize, MEM_COMMIT,
+                  PAGE_READWRITE);
+  if (pa == NULL) {
+    MakeErrMsg(ErrMsg, "Can't allocate RWX Memory: ");
+    return MemoryBlock();
+  }
+
+  MemoryBlock result;
+  result.Address = pa;
+  result.Size = NumPages*pageSize;
+  return result;
+}
+
 bool Memory::ReleaseRWX(MemoryBlock &M, std::string *ErrMsg) {
   if (M.Address == 0 || M.Size == 0) return false;
   if (!VirtualFree(M.Address, 0, MEM_RELEASE))