Build up UnwindPlan::PlanValidAtAddress to recognize some general
indications that the UnwindPlan is invalid -- for instance, a
complete lack of rows, or a row that fails to define a register to
base the CFA off of.
<rdar://problem/15246247>
llvm-svn: 196201
diff --git a/lldb/source/Symbol/UnwindPlan.cpp b/lldb/source/Symbol/UnwindPlan.cpp
index c089a7b..19edea4 100644
--- a/lldb/source/Symbol/UnwindPlan.cpp
+++ b/lldb/source/Symbol/UnwindPlan.cpp
@@ -10,6 +10,7 @@
#include "lldb/Symbol/UnwindPlan.h"
#include "lldb/Core/ConstString.h"
+#include "lldb/Core/Log.h"
#include "lldb/Target/Process.h"
#include "lldb/Target/RegisterContext.h"
#include "lldb/Target/Thread.h"
@@ -373,6 +374,25 @@
bool
UnwindPlan::PlanValidAtAddress (Address addr)
{
+ // If this UnwindPlan has no rows, it is an invalid UnwindPlan.
+ if (GetRowCount() == 0)
+ {
+ Log *log(GetLogIfAllCategoriesSet (LIBLLDB_LOG_UNWIND));
+ if (log)
+ log->Printf ("Testing if UnwindPlan is valid at pc 0x%" PRIx64 ": No unwind rows - is invalid.");
+ return false;
+ }
+
+ // If the 0th Row of unwind instructions is missing, or if it doesn't provide
+ // a register to use to find the Canonical Frame Address, this is not a valid UnwindPlan.
+ if (GetRowAtIndex(0).get() == NULL || GetRowAtIndex(0)->GetCFARegister() == LLDB_INVALID_REGNUM)
+ {
+ Log *log(GetLogIfAllCategoriesSet (LIBLLDB_LOG_UNWIND));
+ if (log)
+ log->Printf ("Testing if UnwindPlan is valid at pc 0x%" PRIx64 ": No CFA register - is invalid.");
+ return false;
+ }
+
if (!m_plan_valid_address_range.GetBaseAddress().IsValid() || m_plan_valid_address_range.GetByteSize() == 0)
return true;