[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, 13 insertions, 0 deletions

diff --git a/lldb/source/Plugins/Process/gdb-remote/ProcessGDBRemote.h b/lldb/source/Plugins/Process/gdb-remote/ProcessGDBRemote.h
index 42d1c4ecd66..10679e0b68d 100644
--- a/lldb/source/Plugins/Process/gdb-remote/ProcessGDBRemote.h
+++ b/lldb/source/Plugins/Process/gdb-remote/ProcessGDBRemote.h
@@ -144,6 +144,8 @@ public:
   size_t DoReadMemory(lldb::addr_t addr, void *buf, size_t size,
                       Status &error) override;
 
+  Status WriteObjectFile(std::vector<WriteEntry> entries) override;
+
   size_t DoWriteMemory(lldb::addr_t addr, const void *buf, size_t size,
                        Status &error) override;
 
@@ -302,6 +304,11 @@ protected:
   int64_t m_breakpoint_pc_offset;
   lldb::tid_t m_initial_tid; // The initial thread ID, given by stub on attach
 
+  bool m_allow_flash_writes;
+  using FlashRangeVector = lldb_private::RangeVector<lldb::addr_t, size_t>;
+  using FlashRange = FlashRangeVector::Entry;
+  FlashRangeVector m_erased_flash_ranges;
+
   //----------------------------------------------------------------------
   // Accessors
   //----------------------------------------------------------------------
@@ -408,6 +415,12 @@ protected:
 
   Status UpdateAutomaticSignalFiltering() override;
 
+  Status FlashErase(lldb::addr_t addr, size_t size);
+
+  Status FlashDone();
+
+  bool HasErased(FlashRange range);
+
 private:
   //------------------------------------------------------------------
   // For ProcessGDBRemote only