A pretty big overhaul of the TryFallbackUnwindPlan method in
RegisterContextLLDB. I have core files of half a dozen tricky
unwind situations on x86/arm and they're all working pretty much
correctly at this point, but we'll need to keep an eye out for
unwinder regressions for a little while; it's tricky to get these
heuristics completely correct in all unwind situations.
<rdar://problem/18937193>
llvm-svn: 221866
diff --git a/lldb/source/Plugins/Process/Utility/UnwindLLDB.cpp b/lldb/source/Plugins/Process/Utility/UnwindLLDB.cpp
index 37fd4f4..b1ca7b2 100644
--- a/lldb/source/Plugins/Process/Utility/UnwindLLDB.cpp
+++ b/lldb/source/Plugins/Process/Utility/UnwindLLDB.cpp
@@ -172,8 +172,9 @@
if (!reg_ctx_sp->IsValid())
{
- // If the RegisterContextLLDB has a fallback UnwindPlan, it will switch to that and return
- // true. Subsequent calls to TryFallbackUnwindPlan() will return false.
+ // We failed to get a valid RegisterContext.
+ // See if the regctx below this on the stack has a fallback unwind plan it can use.
+ // Subsequent calls to TryFallbackUnwindPlan() will return false.
if (m_frames[cur_idx - 1]->reg_ctx_lldb_sp->TryFallbackUnwindPlan())
{
return AddOneMoreFrame (abi);