Cache memory regions in ProcessMinidump and use the linux maps as the source of the information if available

Breakpad creates minidump files that sometimes have:
- linux maps textual content
- no MemoryInfoList

Right now unless the file has a MemoryInfoList we get no region information.

This patch:

- reads and caches the memory region info one time and sorts it for easy subsequent access
- get the region info from the best source in this order:
  - linux maps info (if available)
  - MemoryInfoList (if available)
  - MemoryList or Memory64List
- returns memory region info for the gaps between regions (before the first and after the last)

Differential Revision: https://reviews.llvm.org/D55522

llvm-svn: 349182

1 files changed, 2 insertions, 8 deletions

diff --git a/lldb/source/Plugins/Process/minidump/ProcessMinidump.cpp b/lldb/source/Plugins/Process/minidump/ProcessMinidump.cpp
index 97e13762270..1744b65e38b 100644
--- a/lldb/source/Plugins/Process/minidump/ProcessMinidump.cpp
+++ b/lldb/source/Plugins/Process/minidump/ProcessMinidump.cpp
@@ -284,14 +284,8 @@ ArchSpec ProcessMinidump::GetArchitecture() {
 
 Status ProcessMinidump::GetMemoryRegionInfo(lldb::addr_t load_addr,
                                             MemoryRegionInfo &range_info) {
-  Status error;
-  auto info = m_minidump_parser.GetMemoryRegionInfo(load_addr);
-  if (!info) {
-    error.SetErrorString("No valid MemoryRegionInfo found!");
-    return error;
-  }
-  range_info = info.getValue();
-  return error;
+  range_info = m_minidump_parser.GetMemoryRegionInfo(load_addr);
+  return Status();
 }
 
 void ProcessMinidump::Clear() { Process::m_thread_list.Clear(); }