1 files changed, 59 insertions, 4 deletions
diff --git a/include/llvm/DebugInfo/GSYM/InlineInfo.h b/include/llvm/DebugInfo/GSYM/InlineInfo.h
index 222430622932..48fd9a7c1308 100644
--- a/include/llvm/DebugInfo/GSYM/InlineInfo.h
+++ b/include/llvm/DebugInfo/GSYM/InlineInfo.h
@@ -1,9 +1,8 @@
 //===- InlineInfo.h ---------------------------------------------*- C++ -*-===//
 //
-//                     The LLVM Compiler Infrastructure
-//
-// This file is distributed under the University of Illinois Open Source
-// License. See LICENSE.TXT for details.
+// 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
 //
 //===----------------------------------------------------------------------===//
 
@@ -12,6 +11,7 @@
 
 #include "llvm/ADT/Optional.h"
 #include "llvm/DebugInfo/GSYM/Range.h"
+#include "llvm/Support/Error.h"
 #include <stdint.h>
 #include <vector>
 
@@ -31,6 +31,30 @@ namespace gsym {
 /// Any clients that encode information will need to ensure the ranges are
 /// all contined correctly or lookups could fail. Add ranges in these objects
 /// must be contained in the top level FunctionInfo address ranges as well.
+///
+/// ENCODING
+///
+/// When saved to disk, the inline info encodes all ranges to be relative to
+/// a parent address range. This will be the FunctionInfo's start address if
+/// the InlineInfo is directly contained in a FunctionInfo, or a the start
+/// address of the containing parent InlineInfo's first "Ranges" member. This
+/// allows address ranges to be efficiently encoded using ULEB128 encodings as
+/// we encode the offset and size of each range instead of full addresses. This
+/// also makes any encoded addresses easy to relocate as we just need to
+/// relocate the FunctionInfo's start address.
+///
+/// - The AddressRanges member "Ranges" is encoded using an approriate base
+///   address as described above.
+/// - UINT8 boolean value that specifies if the InlineInfo object has children.
+/// - UINT32 string table offset that points to the name of the inline
+///   function.
+/// - ULEB128 integer that specifies the file of the call site that called
+///   this function.
+/// - ULEB128 integer that specifies the source line of the call site that
+///   called this function.
+/// - if this object has children, enocode each child InlineInfo using the
+///   the first address range's start address as the base address.
+///
 struct InlineInfo {
 
   uint32_t Name; ///< String table offset in the string table.
@@ -62,6 +86,37 @@ struct InlineInfo {
   /// \returns optional vector of InlineInfo objects that describe the
   /// inline call stack for a given address, false otherwise.
   llvm::Optional<InlineArray> getInlineStack(uint64_t Addr) const;
+
+  /// Decode an InlineInfo object from a binary data stream.
+  ///
+  /// \param Data The binary stream to read the data from. This object must
+  /// have the data for the InlineInfo object starting at offset zero. The data
+  /// can contain more data than needed.
+  ///
+  /// \param BaseAddr The base address to use when decoding all address ranges.
+  /// This will be the FunctionInfo's start address if this object is directly
+  /// contained in a FunctionInfo object, or the start address of the first
+  /// address range in an InlineInfo object of this object is a child of
+  /// another InlineInfo object.
+  /// \returns An InlineInfo or an error describing the issue that was
+  /// encountered during decoding.
+  static llvm::Expected<InlineInfo> decode(DataExtractor &Data,
+                                           uint64_t BaseAddr);
+
+  /// Encode this InlineInfo object into FileWriter stream.
+  ///
+  /// \param O The binary stream to write the data to at the current file
+  /// position.
+  ///
+  /// \param BaseAddr The base address to use when encoding all address ranges.
+  /// This will be the FunctionInfo's start address if this object is directly
+  /// contained in a FunctionInfo object, or the start address of the first
+  /// address range in an InlineInfo object of this object is a child of
+  /// another InlineInfo object.
+  ///
+  /// \returns An error object that indicates success or failure or the
+  /// encoding process.
+  llvm::Error encode(FileWriter &O, uint64_t BaseAddr) const;
 };
 
 inline bool operator==(const InlineInfo &LHS, const InlineInfo &RHS) {