1 //===-- ThreadPlanStepOverRange.cpp -----------------------------*- C++ -*-===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 
10 #include "lldb/Target/ThreadPlanStepOverRange.h"
11 
12 // C Includes
13 // C++ Includes
14 // Other libraries and framework includes
15 // Project includes
16 
17 #include "lldb/lldb-private-log.h"
18 #include "lldb/Core/Log.h"
19 #include "lldb/Core/Stream.h"
20 #include "lldb/Target/Process.h"
21 #include "lldb/Target/RegisterContext.h"
22 #include "lldb/Target/Thread.h"
23 #include "lldb/Target/ThreadPlanStepOut.h"
24 #include "lldb/Target/ThreadPlanStepThrough.h"
25 
26 using namespace lldb_private;
27 
28 
29 //----------------------------------------------------------------------
30 // ThreadPlanStepOverRange: Step through a stack range, either stepping over or into
31 // based on the value of \a type.
32 //----------------------------------------------------------------------
33 
34 ThreadPlanStepOverRange::ThreadPlanStepOverRange
35 (
36     Thread &thread,
37     const AddressRange &range,
38     const SymbolContext &addr_context,
39     lldb::RunMode stop_others,
40     bool okay_to_discard
41 ) :
42     ThreadPlanStepRange (ThreadPlan::eKindStepOverRange, "Step range stepping over", thread, range, addr_context, stop_others)
43 {
44     SetOkayToDiscard (okay_to_discard);
45 }
46 
47 ThreadPlanStepOverRange::~ThreadPlanStepOverRange ()
48 {
49 }
50 
51 void
52 ThreadPlanStepOverRange::GetDescription (Stream *s, lldb::DescriptionLevel level)
53 {
54     if (level == lldb::eDescriptionLevelBrief)
55         s->Printf("step over");
56     else
57     {
58         s->Printf ("stepping through range (stepping over functions): ");
59         m_address_range.Dump (s, &m_thread.GetProcess().GetTarget(), Address::DumpStyleLoadAddress);
60     }
61 }
62 
63 bool
64 ThreadPlanStepOverRange::ShouldStop (Event *event_ptr)
65 {
66     Log *log = lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_STEP);
67 
68     if (log)
69     {
70         StreamString s;
71         s.Address (m_thread.GetRegisterContext()->GetPC(), m_thread.GetProcess().GetAddressByteSize());
72         log->Printf("ThreadPlanStepOverRange reached %s.", s.GetData());
73     }
74 
75     // If we're still in the range, keep going.
76     if (InRange())
77         return false;
78 
79     // If we're out of the range but in the same frame or in our caller's frame
80     // then we should stop.
81     // When stepping out we only step if we are forcing running one thread.
82     bool stop_others;
83     if (m_stop_others == lldb::eOnlyThisThread)
84         stop_others = true;
85     else
86         stop_others = false;
87 
88     ThreadPlan* new_plan = NULL;
89 
90     if (FrameIsOlder())
91     {
92         // If we're in an older frame then we should stop.
93         //
94         // A caveat to this is if we think the frame is older but we're actually in a trampoline.
95         // I'm going to make the assumption that you wouldn't RETURN to a trampoline.  So if we are
96         // in a trampoline we think the frame is older because the trampoline confused the backtracer.
97         // As below, we step through first, and then try to figure out how to get back out again.
98 
99         new_plan = m_thread.QueueThreadPlanForStepThrough (false, stop_others);
100 
101         if (new_plan != NULL && log)
102             log->Printf("Thought I stepped out, but in fact arrived at a trampoline.");
103     }
104     else if (FrameIsYounger())
105     {
106         new_plan = m_thread.QueueThreadPlanForStepOut (false, NULL, true, stop_others, lldb::eVoteNo, lldb::eVoteNoOpinion);
107     }
108     else if (!InSymbol())
109     {
110         // This one is a little tricky.  Sometimes we may be in a stub or something similar,
111         // in which case we need to get out of there.  But if we are in a stub then it's
112         // likely going to be hard to get out from here.  It is probably easiest to step into the
113         // stub, and then it will be straight-forward to step out.
114         new_plan = m_thread.QueueThreadPlanForStepThrough (false, stop_others);
115     }
116 
117     if (new_plan == NULL)
118         m_no_more_plans = true;
119     else
120         m_no_more_plans = false;
121 
122     if (new_plan == NULL)
123     {
124         // For efficiencies sake, we know we're done here so we don't have to do this
125         // calculation again in MischiefManaged.
126         SetPlanComplete();
127         return true;
128     }
129     else
130         return false;
131 }
132