1 //===-- StackID.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/StackID.h"
11 
12 // C Includes
13 // C++ Includes
14 // Other libraries and framework includes
15 // Project includes
16 #include "lldb/Core/Stream.h"
17 #include "lldb/Symbol/Block.h"
18 #include "lldb/Symbol/Symbol.h"
19 #include "lldb/Symbol/SymbolContext.h"
20 
21 using namespace lldb_private;
22 
23 
24 void
25 StackID::Dump (Stream *s)
26 {
27     s->Printf("StackID (pc = 0x%16.16" PRIx64 ", cfa = 0x%16.16" PRIx64 ", symbol_scope = %p",
28               m_pc, m_cfa, static_cast<void*>(m_symbol_scope));
29     if (m_symbol_scope)
30     {
31         SymbolContext sc;
32 
33         m_symbol_scope->CalculateSymbolContext (&sc);
34         if (sc.block)
35             s->Printf(" (Block {0x%8.8" PRIx64 "})", sc.block->GetID());
36         else if (sc.symbol)
37             s->Printf(" (Symbol{0x%8.8x})", sc.symbol->GetID());
38     }
39     s->PutCString(") ");
40 }
41 
42 bool
43 lldb_private::operator== (const StackID& lhs, const StackID& rhs)
44 {
45     if (lhs.GetCallFrameAddress() != rhs.GetCallFrameAddress())
46         return false;
47 
48     SymbolContextScope *lhs_scope = lhs.GetSymbolContextScope();
49     SymbolContextScope *rhs_scope = rhs.GetSymbolContextScope();
50 
51     // Only compare the PC values if both symbol context scopes are NULL
52     if (lhs_scope == NULL && rhs_scope == NULL)
53         return lhs.GetPC() == rhs.GetPC();
54 
55     return lhs_scope == rhs_scope;
56 }
57 
58 bool
59 lldb_private::operator!= (const StackID& lhs, const StackID& rhs)
60 {
61     if (lhs.GetCallFrameAddress() != rhs.GetCallFrameAddress())
62         return true;
63 
64     SymbolContextScope *lhs_scope = lhs.GetSymbolContextScope();
65     SymbolContextScope *rhs_scope = rhs.GetSymbolContextScope();
66 
67     if (lhs_scope == NULL && rhs_scope == NULL)
68         return lhs.GetPC() != rhs.GetPC();
69 
70     return lhs_scope != rhs_scope;
71 }
72 
73 bool
74 lldb_private::operator< (const StackID& lhs, const StackID& rhs)
75 {
76     const lldb::addr_t lhs_cfa = lhs.GetCallFrameAddress();
77     const lldb::addr_t rhs_cfa = rhs.GetCallFrameAddress();
78 
79     // FIXME: We are assuming that the stacks grow downward in memory.  That's not necessary, but true on
80     // all the machines we care about at present.  If this changes, we'll have to deal with that.  The ABI is the
81     // agent who knows this ordering, but the StackID has no access to the ABI.  The most straightforward way
82     // to handle this is to add a "m_grows_downward" bool to the StackID, and set it in the constructor.
83     // But I'm not going to waste a bool per StackID on this till we need it.
84 
85     if (lhs_cfa != rhs_cfa)
86         return lhs_cfa < rhs_cfa;
87 
88     SymbolContextScope *lhs_scope = lhs.GetSymbolContextScope();
89     SymbolContextScope *rhs_scope = rhs.GetSymbolContextScope();
90 
91     if (lhs_scope != NULL && rhs_scope != NULL)
92     {
93         // Same exact scope, lhs is not less than (younger than rhs)
94         if (lhs_scope == rhs_scope)
95             return false;
96 
97         SymbolContext lhs_sc;
98         SymbolContext rhs_sc;
99         lhs_scope->CalculateSymbolContext (&lhs_sc);
100         rhs_scope->CalculateSymbolContext (&rhs_sc);
101 
102         // Items with the same function can only be compared
103         if (lhs_sc.function == rhs_sc.function &&
104             lhs_sc.function != NULL && lhs_sc.block != NULL &&
105             rhs_sc.function != NULL && rhs_sc.block != NULL)
106         {
107             return rhs_sc.block->Contains (lhs_sc.block);
108         }
109     }
110     return false;
111 }
112