1 //===-- HistoryUnwind.cpp ---------------------------------------*- C++ -*-===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 
9 #include "lldb/lldb-private.h"
10 
11 #include "Plugins/Process/Utility/HistoryUnwind.h"
12 #include "Plugins/Process/Utility/RegisterContextHistory.h"
13 
14 #include "lldb/Target/Process.h"
15 #include "lldb/Target/StackFrame.h"
16 #include "lldb/Target/Target.h"
17 #include "lldb/Target/Thread.h"
18 
19 using namespace lldb;
20 using namespace lldb_private;
21 
22 // Constructor
23 
24 HistoryUnwind::HistoryUnwind(Thread &thread, std::vector<lldb::addr_t> pcs,
25                              bool stop_id_is_valid)
26     : Unwind(thread), m_pcs(pcs), m_stop_id_is_valid(stop_id_is_valid) {}
27 
28 // Destructor
29 
30 HistoryUnwind::~HistoryUnwind() {}
31 
32 void HistoryUnwind::DoClear() {
33   std::lock_guard<std::recursive_mutex> guard(m_unwind_mutex);
34   m_pcs.clear();
35   m_stop_id_is_valid = false;
36 }
37 
38 lldb::RegisterContextSP
39 HistoryUnwind::DoCreateRegisterContextForFrame(StackFrame *frame) {
40   RegisterContextSP rctx;
41   if (frame) {
42     addr_t pc = frame->GetFrameCodeAddress().GetLoadAddress(
43         &frame->GetThread()->GetProcess()->GetTarget());
44     if (pc != LLDB_INVALID_ADDRESS) {
45       rctx.reset(new RegisterContextHistory(
46           *frame->GetThread().get(), frame->GetConcreteFrameIndex(),
47           frame->GetThread()->GetProcess()->GetAddressByteSize(), pc));
48     }
49   }
50   return rctx;
51 }
52 
53 bool HistoryUnwind::DoGetFrameInfoAtIndex(uint32_t frame_idx, lldb::addr_t &cfa,
54                                           lldb::addr_t &pc) {
55   // FIXME do not throw away the lock after we acquire it..
56   std::unique_lock<std::recursive_mutex> guard(m_unwind_mutex);
57   guard.unlock();
58   if (frame_idx < m_pcs.size()) {
59     cfa = frame_idx;
60     pc = m_pcs[frame_idx];
61     return true;
62   }
63   return false;
64 }
65 
66 uint32_t HistoryUnwind::DoGetFrameCount() { return m_pcs.size(); }
67