Improve PowerPC unwind support

Summary:
Taking advantage of the new 'CFAIsRegisterDereferenced' CFA register type, add
full stack unwind support to the PowerPC/PowerPC64 ABI.  Also, add a new
register set for powerpc32-on-64, so the register sizes are correct.  This also
requires modifying the ProcessMonitor to add support for non-uintptr_t-sized
register values.

Reviewers: jasonmolenda, emaste

Subscribers: emaste, lldb-commits

Differential Revision: http://reviews.llvm.org/D6183

llvm-svn: 221789

1 files changed, 6 insertions, 1 deletions

diff --git a/lldb/source/Plugins/Process/POSIX/RegisterContextPOSIXProcessMonitor_powerpc.cpp b/lldb/source/Plugins/Process/POSIX/RegisterContextPOSIXProcessMonitor_powerpc.cpp
index 0dfb91d5e4e..b542db4779d 100644
--- a/lldb/source/Plugins/Process/POSIX/RegisterContextPOSIXProcessMonitor_powerpc.cpp
+++ b/lldb/source/Plugins/Process/POSIX/RegisterContextPOSIXProcessMonitor_powerpc.cpp
@@ -123,8 +123,13 @@ RegisterContextPOSIXProcessMonitor_powerpc::WriteRegister(const unsigned reg,
     }
 
     ProcessMonitor &monitor = GetMonitor();
+    // Account for the fact that 32-bit targets on powerpc64 really use 64-bit
+    // registers in ptrace, but expose here 32-bit registers with a higher
+    // offset.
+    uint64_t offset = GetRegisterOffset(reg_to_write);
+    offset &= ~(sizeof(uintptr_t) - 1);
     return monitor.WriteRegisterValue(m_thread.GetID(),
-                                      GetRegisterOffset(reg_to_write),
+                                      offset,
                                       GetRegisterName(reg_to_write),
                                       value_to_write);
 }