lldb-server: add support for binary memory reads

Summary:
This commit adds support for binary memory reads ($x) to lldb-server. It also removes the "0x"
prefix from the $x client packet, to make it more compatible with the old $m packet. This allows
us to use almost the same code for handling both packet types. I have verified that debugserver
correctly handles $x packets even without the leading "0x". I have added a test which verifies
that the stub returns the same memory contents for both kinds of memory reads ($x and $m).

Reviewers: tberghammer, jasonmolenda

Subscribers: iancottrell, lldb-commits

Differential Revision: http://reviews.llvm.org/D13695

llvm-svn: 250295

1 files changed, 2 insertions, 8 deletions

diff --git a/lldb/source/Plugins/Process/gdb-remote/ProcessGDBRemote.cpp b/lldb/source/Plugins/Process/gdb-remote/ProcessGDBRemote.cpp
index 895fc05aa36..960730b32b7 100644
--- a/lldb/source/Plugins/Process/gdb-remote/ProcessGDBRemote.cpp
+++ b/lldb/source/Plugins/Process/gdb-remote/ProcessGDBRemote.cpp
@@ -3043,14 +3043,8 @@ ProcessGDBRemote::DoReadMemory (addr_t addr, void *buf, size_t size, Error &erro
     char packet[64];
     int packet_len;
     bool binary_memory_read = m_gdb_comm.GetxPacketSupported();
-    if (binary_memory_read)
-    {
-        packet_len = ::snprintf (packet, sizeof(packet), "x0x%" PRIx64 ",0x%" PRIx64, (uint64_t)addr, (uint64_t)size);
-    }
-    else
-    {
-        packet_len = ::snprintf (packet, sizeof(packet), "m%" PRIx64 ",%" PRIx64, (uint64_t)addr, (uint64_t)size);
-    }
+    packet_len = ::snprintf(packet, sizeof(packet), "%c%" PRIx64 ",%" PRIx64,
+                            binary_memory_read ? 'x' : 'm', (uint64_t)addr, (uint64_t)size);
     assert (packet_len + 1 < (int)sizeof(packet));
     StringExtractorGDBRemote response;
     if (m_gdb_comm.SendPacketAndWaitForResponse(packet, packet_len, response, true) == GDBRemoteCommunication::PacketResult::Success)