1 //===-- HistoryUnwind.cpp -------------------------------------------------===//
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 #include <memory>
20
21 using namespace lldb;
22 using namespace lldb_private;
23
24 // Constructor
25
HistoryUnwind(Thread & thread,std::vector<lldb::addr_t> pcs,bool pcs_are_call_addresses)26 HistoryUnwind::HistoryUnwind(Thread &thread, std::vector<lldb::addr_t> pcs,
27 bool pcs_are_call_addresses)
28 : Unwind(thread), m_pcs(pcs),
29 m_pcs_are_call_addresses(pcs_are_call_addresses) {}
30
31 // Destructor
32
33 HistoryUnwind::~HistoryUnwind() = default;
34
DoClear()35 void HistoryUnwind::DoClear() {
36 std::lock_guard<std::recursive_mutex> guard(m_unwind_mutex);
37 m_pcs.clear();
38 }
39
40 lldb::RegisterContextSP
DoCreateRegisterContextForFrame(StackFrame * frame)41 HistoryUnwind::DoCreateRegisterContextForFrame(StackFrame *frame) {
42 RegisterContextSP rctx;
43 if (frame) {
44 addr_t pc = frame->GetFrameCodeAddress().GetLoadAddress(
45 &frame->GetThread()->GetProcess()->GetTarget());
46 if (pc != LLDB_INVALID_ADDRESS) {
47 rctx = std::make_shared<RegisterContextHistory>(
48 *frame->GetThread().get(), frame->GetConcreteFrameIndex(),
49 frame->GetThread()->GetProcess()->GetAddressByteSize(), pc);
50 }
51 }
52 return rctx;
53 }
54
DoGetFrameInfoAtIndex(uint32_t frame_idx,lldb::addr_t & cfa,lldb::addr_t & pc,bool & behaves_like_zeroth_frame)55 bool HistoryUnwind::DoGetFrameInfoAtIndex(uint32_t frame_idx, lldb::addr_t &cfa,
56 lldb::addr_t &pc,
57 bool &behaves_like_zeroth_frame) {
58 // FIXME do not throw away the lock after we acquire it..
59 std::unique_lock<std::recursive_mutex> guard(m_unwind_mutex);
60 guard.unlock();
61 if (frame_idx < m_pcs.size()) {
62 cfa = frame_idx;
63 pc = m_pcs[frame_idx];
64 if (m_pcs_are_call_addresses)
65 behaves_like_zeroth_frame = true;
66 else
67 behaves_like_zeroth_frame = (frame_idx == 0);
68 return true;
69 }
70 return false;
71 }
72
DoGetFrameCount()73 uint32_t HistoryUnwind::DoGetFrameCount() { return m_pcs.size(); }
74