[lldb] Use vFlash commands when writing to target's flash memory regions

Summary:
When writing an object file over gdb-remote, use the vFlashErase, vFlashWrite, and vFlashDone commands if the write address is in a flash memory region.  A bare metal target may have this kind of setup.

- Update ObjectFileELF to set load addresses using physical addresses.  A typical case may be a data section with a physical address in ROM and a virtual address in RAM, which should be loaded to the ROM address.
- Add support for querying the target's qXfer:memory-map, which contains information about flash memory regions, leveraging MemoryRegionInfo data structures with minor modifications
- Update ProcessGDBRemote to use vFlash commands in DoWriteMemory when the target address is in a flash region

Original discussion at http://lists.llvm.org/pipermail/lldb-dev/2018-January/013093.html

Reviewers: clayborg, labath

Reviewed By: labath

Subscribers: arichardson, emaste, mgorny, lldb-commits

Differential Revision: https://reviews.llvm.org/D42145
Patch by Owen Shaw <llvm@owenpshaw.net>

llvm-svn: 326261

1 files changed, 11 insertions, 0 deletions

diff --git a/lldb/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationClient.h b/lldb/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationClient.h
index 45913157c29..8898767e83c 100644
--- a/lldb/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationClient.h
+++ b/lldb/source/Plugins/Process/gdb-remote/GDBRemoteCommunicationClient.h
@@ -355,6 +355,8 @@ public:
 
   bool GetQXferFeaturesReadSupported();
 
+  bool GetQXferMemoryMapReadSupported();
+
   LazyBool SupportsAllocDeallocMemory() // const
   {
     // Uncomment this to have lldb pretend the debug server doesn't respond to
@@ -545,6 +547,7 @@ protected:
   LazyBool m_supports_qXfer_libraries_read;
   LazyBool m_supports_qXfer_libraries_svr4_read;
   LazyBool m_supports_qXfer_features_read;
+  LazyBool m_supports_qXfer_memory_map_read;
   LazyBool m_supports_augmented_libraries_svr4_read;
   LazyBool m_supports_jThreadExtendedInfo;
   LazyBool m_supports_jLoadedDynamicLibrariesInfos;
@@ -588,6 +591,9 @@ protected:
   bool m_supported_async_json_packets_is_valid;
   lldb_private::StructuredData::ObjectSP m_supported_async_json_packets_sp;
 
+  std::vector<MemoryRegionInfo> m_qXfer_memory_map;
+  bool m_qXfer_memory_map_loaded;
+
   bool GetCurrentProcessInfo(bool allow_lazy_pid = true);
 
   bool GetGDBServerVersion();
@@ -610,6 +616,11 @@ protected:
                                 llvm::MutableArrayRef<uint8_t> &buffer,
                                 size_t offset);
 
+  Status LoadQXferMemoryMap();
+
+  Status GetQXferMemoryMapRegionInfo(lldb::addr_t addr,
+                                     MemoryRegionInfo &region);
+
 private:
   DISALLOW_COPY_AND_ASSIGN(GDBRemoteCommunicationClient);
 };