1 //===- SmallVectorMemoryBuffer.h --------------------------------*- C++ -*-===// 2 // 3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4 // See https://llvm.org/LICENSE.txt for license information. 5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6 // 7 //===----------------------------------------------------------------------===// 8 // 9 // This file declares a wrapper class to hold the memory into which an 10 // object will be generated. 11 // 12 //===----------------------------------------------------------------------===// 13 14 #ifndef LLVM_EXECUTIONENGINE_OBJECTMEMORYBUFFER_H 15 #define LLVM_EXECUTIONENGINE_OBJECTMEMORYBUFFER_H 16 17 #include "llvm/ADT/SmallVector.h" 18 #include "llvm/Support/MemoryBuffer.h" 19 #include "llvm/Support/raw_ostream.h" 20 21 namespace llvm { 22 23 /// SmallVector-backed MemoryBuffer instance. 24 /// 25 /// This class enables efficient construction of MemoryBuffers from SmallVector 26 /// instances. This is useful for MCJIT and Orc, where object files are streamed 27 /// into SmallVectors, then inspected using ObjectFile (which takes a 28 /// MemoryBuffer). 29 class SmallVectorMemoryBuffer : public MemoryBuffer { 30 public: 31 /// Construct an SmallVectorMemoryBuffer from the given SmallVector 32 /// r-value. 33 /// 34 /// FIXME: It'd be nice for this to be a non-templated constructor taking a 35 /// SmallVectorImpl here instead of a templated one taking a SmallVector<N>, 36 /// but SmallVector's move-construction/assignment currently only take 37 /// SmallVectors. If/when that is fixed we can simplify this constructor and 38 /// the following one. SmallVectorMemoryBuffer(SmallVectorImpl<char> && SV)39 SmallVectorMemoryBuffer(SmallVectorImpl<char> &&SV) 40 : SV(std::move(SV)), BufferName("<in-memory object>") { 41 init(this->SV.begin(), this->SV.end(), false); 42 } 43 44 /// Construct a named SmallVectorMemoryBuffer from the given 45 /// SmallVector r-value and StringRef. SmallVectorMemoryBuffer(SmallVectorImpl<char> && SV,StringRef Name)46 SmallVectorMemoryBuffer(SmallVectorImpl<char> &&SV, StringRef Name) 47 : SV(std::move(SV)), BufferName(std::string(Name)) { 48 init(this->SV.begin(), this->SV.end(), false); 49 } 50 51 // Key function. 52 ~SmallVectorMemoryBuffer() override; 53 getBufferIdentifier()54 StringRef getBufferIdentifier() const override { return BufferName; } 55 getBufferKind()56 BufferKind getBufferKind() const override { return MemoryBuffer_Malloc; } 57 58 private: 59 SmallVector<char, 0> SV; 60 std::string BufferName; 61 }; 62 63 } // namespace llvm 64 65 #endif 66