vendor/llvm/llvm-trunk-r338150

1 files changed, 64 insertions, 0 deletions

diff --git a/include/llvm/Support/SmallVectorMemoryBuffer.h b/include/llvm/Support/SmallVectorMemoryBuffer.h
new file mode 100644
index 000000000000..f43c2fb8f826
--- /dev/null
+++ b/include/llvm/Support/SmallVectorMemoryBuffer.h
@@ -0,0 +1,64 @@
+//===- SmallVectorMemoryBuffer.h --------------------------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file declares a wrapper class to hold the memory into which an
+// object will be generated.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_EXECUTIONENGINE_OBJECTMEMORYBUFFER_H
+#define LLVM_EXECUTIONENGINE_OBJECTMEMORYBUFFER_H
+
+#include "llvm/ADT/SmallVector.h"
+#include "llvm/Support/MemoryBuffer.h"
+#include "llvm/Support/raw_ostream.h"
+
+namespace llvm {
+
+/// SmallVector-backed MemoryBuffer instance.
+///
+/// This class enables efficient construction of MemoryBuffers from SmallVector
+/// instances. This is useful for MCJIT and Orc, where object files are streamed
+/// into SmallVectors, then inspected using ObjectFile (which takes a
+/// MemoryBuffer).
+class SmallVectorMemoryBuffer : public MemoryBuffer {
+public:
+  /// Construct an SmallVectorMemoryBuffer from the given SmallVector
+  /// r-value.
+  ///
+  /// FIXME: It'd be nice for this to be a non-templated constructor taking a
+  /// SmallVectorImpl here instead of a templated one taking a SmallVector<N>,
+  /// but SmallVector's move-construction/assignment currently only take
+  /// SmallVectors. If/when that is fixed we can simplify this constructor and
+  /// the following one.
+  SmallVectorMemoryBuffer(SmallVectorImpl<char> &&SV)
+      : SV(std::move(SV)), BufferName("<in-memory object>") {
+    init(this->SV.begin(), this->SV.end(), false);
+  }
+
+  /// Construct a named SmallVectorMemoryBuffer from the given
+  /// SmallVector r-value and StringRef.
+  SmallVectorMemoryBuffer(SmallVectorImpl<char> &&SV, StringRef Name)
+      : SV(std::move(SV)), BufferName(Name) {
+    init(this->SV.begin(), this->SV.end(), false);
+  }
+
+  StringRef getBufferIdentifier() const override { return BufferName; }
+
+  BufferKind getBufferKind() const override { return MemoryBuffer_Malloc; }
+
+private:
+  SmallVector<char, 0> SV;
+  std::string BufferName;
+  void anchor() override;
+};
+
+} // namespace llvm
+
+#endif