Add setting to require hardware breakpoints.

When debugging read-only memory we cannot use software breakpoint. We
already have support for hardware breakpoints and users can specify them
with `-H`. However, there's no option to force LLDB to use hardware
breakpoints internally, for example while stepping.

This patch adds a setting target.require-hardware-breakpoint that forces
LLDB to always use hardware breakpoints. Because hardware breakpoints
are a limited resource and can fail to resolve, this patch also extends
error handling in thread plans, where breakpoints are used for stepping.

Differential revision: https://reviews.llvm.org/D54221

llvm-svn: 346920

1 files changed, 4 insertions, 3 deletions

diff --git a/lldb/source/Target/ThreadPlanCallOnFunctionExit.cpp b/lldb/source/Target/ThreadPlanCallOnFunctionExit.cpp
index e8ea73f3c6a..2ea083dac45 100644
--- a/lldb/source/Target/ThreadPlanCallOnFunctionExit.cpp
+++ b/lldb/source/Target/ThreadPlanCallOnFunctionExit.cpp
@@ -27,17 +27,18 @@ void ThreadPlanCallOnFunctionExit::DidPush() {
   // completes.
 
   // Set stop vote to eVoteNo.
+  Status status;
   m_step_out_threadplan_sp = GetThread().QueueThreadPlanForStepOut(
       false,             // abort other plans
       nullptr,           // addr_context
       true,              // first instruction
       true,              // stop other threads
       eVoteNo,           // do not say "we're stopping"
-      eVoteNoOpinion,    // don't care about
-                         // run state broadcasting
+      eVoteNoOpinion,    // don't care about run state broadcasting
       0,                 // frame_idx
+      status,            // status
       eLazyBoolCalculate // avoid code w/o debinfo
-      );
+  );
 }
 
 // -------------------------------------------------------------------------