1 files changed, 121 insertions, 0 deletions
diff --git a/llvm/lib/CodeGen/AsmPrinter/ByteStreamer.h b/llvm/lib/CodeGen/AsmPrinter/ByteStreamer.h
new file mode 100644
index 000000000000..09f7496cd4ef
--- /dev/null
+++ b/llvm/lib/CodeGen/AsmPrinter/ByteStreamer.h
@@ -0,0 +1,121 @@
+//===-- llvm/CodeGen/ByteStreamer.h - ByteStreamer class --------*- C++ -*-===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+//
+// This file contains a class that can take bytes that would normally be
+// streamed via the AsmPrinter.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_LIB_CODEGEN_ASMPRINTER_BYTESTREAMER_H
+#define LLVM_LIB_CODEGEN_ASMPRINTER_BYTESTREAMER_H
+
+#include "DIEHash.h"
+#include "llvm/CodeGen/AsmPrinter.h"
+#include "llvm/MC/MCStreamer.h"
+#include "llvm/Support/LEB128.h"
+#include <string>
+
+namespace llvm {
+class ByteStreamer {
+ protected:
+  ~ByteStreamer() = default;
+  ByteStreamer(const ByteStreamer&) = default;
+  ByteStreamer() = default;
+
+ public:
+  // For now we're just handling the calls we need for dwarf emission/hashing.
+  virtual void EmitInt8(uint8_t Byte, const Twine &Comment = "") = 0;
+  virtual void EmitSLEB128(uint64_t DWord, const Twine &Comment = "") = 0;
+  virtual void EmitULEB128(uint64_t DWord, const Twine &Comment = "", unsigned PadTo = 0) = 0;
+};
+
+class APByteStreamer final : public ByteStreamer {
+private:
+  AsmPrinter &AP;
+
+public:
+  APByteStreamer(AsmPrinter &Asm) : AP(Asm) {}
+  void EmitInt8(uint8_t Byte, const Twine &Comment) override {
+    AP.OutStreamer->AddComment(Comment);
+    AP.emitInt8(Byte);
+  }
+  void EmitSLEB128(uint64_t DWord, const Twine &Comment) override {
+    AP.OutStreamer->AddComment(Comment);
+    AP.EmitSLEB128(DWord);
+  }
+  void EmitULEB128(uint64_t DWord, const Twine &Comment, unsigned PadTo) override {
+    AP.OutStreamer->AddComment(Comment);
+    AP.EmitULEB128(DWord);
+  }
+};
+
+class HashingByteStreamer final : public ByteStreamer {
+ private:
+  DIEHash &Hash;
+ public:
+ HashingByteStreamer(DIEHash &H) : Hash(H) {}
+  void EmitInt8(uint8_t Byte, const Twine &Comment) override {
+    Hash.update(Byte);
+  }
+  void EmitSLEB128(uint64_t DWord, const Twine &Comment) override {
+    Hash.addSLEB128(DWord);
+  }
+  void EmitULEB128(uint64_t DWord, const Twine &Comment, unsigned PadTo) override {
+    Hash.addULEB128(DWord);
+  }
+};
+
+class BufferByteStreamer final : public ByteStreamer {
+private:
+  SmallVectorImpl<char> &Buffer;
+  std::vector<std::string> &Comments;
+
+public:
+  /// Only verbose textual output needs comments.  This will be set to
+  /// true for that case, and false otherwise.  If false, comments passed in to
+  /// the emit methods will be ignored.
+  const bool GenerateComments;
+
+  BufferByteStreamer(SmallVectorImpl<char> &Buffer,
+                     std::vector<std::string> &Comments, bool GenerateComments)
+      : Buffer(Buffer), Comments(Comments), GenerateComments(GenerateComments) {
+  }
+  void EmitInt8(uint8_t Byte, const Twine &Comment) override {
+    Buffer.push_back(Byte);
+    if (GenerateComments)
+      Comments.push_back(Comment.str());
+  }
+  void EmitSLEB128(uint64_t DWord, const Twine &Comment) override {
+    raw_svector_ostream OSE(Buffer);
+    unsigned Length = encodeSLEB128(DWord, OSE);
+    if (GenerateComments) {
+      Comments.push_back(Comment.str());
+      // Add some empty comments to keep the Buffer and Comments vectors aligned
+      // with each other.
+      for (size_t i = 1; i < Length; ++i)
+        Comments.push_back("");
+
+    }
+  }
+  void EmitULEB128(uint64_t DWord, const Twine &Comment, unsigned PadTo) override {
+    raw_svector_ostream OSE(Buffer);
+    unsigned Length = encodeULEB128(DWord, OSE, PadTo);
+    if (GenerateComments) {
+      Comments.push_back(Comment.str());
+      // Add some empty comments to keep the Buffer and Comments vectors aligned
+      // with each other.
+      for (size_t i = 1; i < Length; ++i)
+        Comments.push_back("");
+
+    }
+  }
+};
+
+}
+
+#endif