[Lldb-commits] [PATCH] D24124: [LLDB][MIPS] Fix register read/write for big endian

[Nitesh Jain via lldb-commits]

nitesh.jain added inline comments.

================
Comment at: source/Plugins/Process/gdb-remote/GDBRemoteCommunicationServerLLGS.cpp:1844
@@ +1843,3 @@
+    
+    uint64_t value;
+    value = reg_size == 4 ? *(uint32_t *)reg_bytes : *(uint64_t *)reg_bytes;
----------------
labath wrote:
> This looks like a massive hack. The register value object already takes a byte order as a parameter, so the fact that you are doing some funny endian conversions here means that there is something wrong. Also, this probably will not work for registers whose sizes are not 4 or 8 (%ah, %ax, all SSE registers, etc.).
> 
> I think we'll need to find a different way to fix this.
The problem is  with RegisterValue.SetBytes 

RegisterValue (uint8_t *bytes, size_t length, lldb::ByteOrder byte_order)
        {
            SetBytes (bytes, length, byte_order);
        }

The RegisterValue.SetBytes use memcpy to perform copy . So for register whose size is 4 it will be copy to lower 32bit LSB and hence RegisterValue.GetAsUInt64 will give incorrect result for 32 bit big endian system. 


https://reviews.llvm.org/D24124