Add support for FreeBSD arm live debugging

[emaste]

Summary

Fix RegisterContextPOSIX_arm::GetReisterSet
The target trip should be 'arm' not 'aarch64'

Add sw brkpt insn to PlatformFreeBSD::GetSoftwareBreakpointTrapOpcode

[omjavaid]

Its easier to review full context diffs. Please generate it using (git diff -U999999 or svn diff --diff-cmd=diff -x -U999999)

source/Plugins/Platform/FreeBSD/PlatformFreeBSD.cpp

347

Please add case for arm in alphabetical order before ppc.

Also add a TODO to handle both (little/big endian) arm and thumb mode trap codes.

[trixirt]

Handle thumb breakpoints
Detect when in thumb code and silently disable breakpoints
FreeBSD does not support thumb breakpoints.
Define a reasonable breakpoint instruction to enable when thumb breakpoints are supported

[emaste]

Seems I didn't get any email notification from Phabricator for this :(
I will extract the thumb part and apply it.

source/Plugins/Process/POSIX/POSIXThread.cpp

179

Whitespace issue?

[emaste]

Extract thumb opcode stub from original change and sync whitespace etc. with PlatformLinux.cpp

[trixirt]

Thanks!

There is also a change to support core file reading, that I believe is
ready.
http://reviews.llvm.org/D9292

Tom

source/Plugins/Platform/FreeBSD/PlatformFreeBSD.cpp

             trap_opcode = g_ppc_opcode;
             trap_opcode_size = sizeof(g_ppc_opcode);
         }
+    case llvm::Triple::arm:
+        {
+            static const uint8_t g_arm_opcode[] = { 0xfe, 0xde, 0xff, 0xe7 };
+            trap_opcode = g_arm_opcode;
+            trap_opcode_size = sizeof(g_arm_opcode);
+        }
     }
 
     if (bp_site->SetTrapOpcode(trap_opcode, trap_opcode_size))

source/Plugins/Process/POSIX/POSIXThread.cpp

 #include "Plugins/Process/Utility/RegisterContextLinux_arm64.h"
 #include "Plugins/Process/Utility/RegisterContextLinux_i386.h"
 #include "Plugins/Process/Utility/RegisterContextLinux_x86_64.h"
+#include "Plugins/Process/Utility/RegisterContextFreeBSD_arm.h"
 #include "Plugins/Process/Utility/RegisterContextFreeBSD_i386.h"
 #include "Plugins/Process/Utility/RegisterContextFreeBSD_mips64.h"
 #include "Plugins/Process/Utility/RegisterContextFreeBSD_powerpc.h"

             case llvm::Triple::FreeBSD:
                 switch (target_arch.GetMachine())
                 {
-                    case llvm::Triple::ppc:
+                    case llvm::Triple::arm:
+                        reg_interface = new RegisterContextFreeBSD_arm(target_arch);
+                        break;
+
+        case llvm::Triple::ppc:
 #ifndef __powerpc64__
                         reg_interface = new RegisterContextFreeBSD_powerpc32(target_arch);
                         break;