StackID.cpp revision 254721 
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
21using namespace lldb_private;
22
23
24void
25StackID::Dump (Stream *s)
26{
27    s->Printf("StackID (pc = 0x%16.16" PRIx64 ", cfa = 0x%16.16" PRIx64 ", symbol_scope = %p", (uint64_t)m_pc, (uint64_t)m_cfa, m_symbol_scope);
28    if (m_symbol_scope)
29    {
30        SymbolContext sc;
31
32        m_symbol_scope->CalculateSymbolContext (&sc);
33        if (sc.block)
34            s->Printf(" (Block {0x%8.8" PRIx64 "})", sc.block->GetID());
35        else if (sc.symbol)
36            s->Printf(" (Symbol{0x%8.8x})", sc.symbol->GetID());
37    }
38    s->PutCString(") ");
39}
40
41bool
42lldb_private::operator== (const StackID& lhs, const StackID& rhs)
43{
44    if (lhs.GetCallFrameAddress() != rhs.GetCallFrameAddress())
45        return false;
46
47    SymbolContextScope *lhs_scope = lhs.GetSymbolContextScope();
48    SymbolContextScope *rhs_scope = rhs.GetSymbolContextScope();
49
50    // Only compare the PC values if both symbol context scopes are NULL
51    if (lhs_scope == NULL && rhs_scope == NULL)
52        return lhs.GetPC() == rhs.GetPC();
53
54    return lhs_scope == rhs_scope;
55}
56
57bool
58lldb_private::operator!= (const StackID& lhs, const StackID& rhs)
59{
60    if (lhs.GetCallFrameAddress() != rhs.GetCallFrameAddress())
61        return true;
62
63    SymbolContextScope *lhs_scope = lhs.GetSymbolContextScope();
64    SymbolContextScope *rhs_scope = rhs.GetSymbolContextScope();
65
66    if (lhs_scope == NULL && rhs_scope == NULL)
67        return lhs.GetPC() != rhs.GetPC();
68
69    return lhs_scope != rhs_scope;
70}
71
72bool
73lldb_private::operator< (const StackID& lhs, const StackID& rhs)
74{
75    const lldb::addr_t lhs_cfa = lhs.GetCallFrameAddress();
76    const lldb::addr_t rhs_cfa = rhs.GetCallFrameAddress();
77
78    // FIXME: We are assuming that the stacks grow downward in memory.  That's not necessary, but true on
79    // all the machines we care about at present.  If this changes, we'll have to deal with that.  The ABI is the
80    // agent who knows this ordering, but the StackID has no access to the ABI.  The most straightforward way
81    // to handle this is to add a "m_grows_downward" bool to the StackID, and set it in the constructor.
82    // But I'm not going to waste a bool per StackID on this till we need it.
83
84    if (lhs_cfa != rhs_cfa)
85        return lhs_cfa < rhs_cfa;
86
87    SymbolContextScope *lhs_scope = lhs.GetSymbolContextScope();
88    SymbolContextScope *rhs_scope = rhs.GetSymbolContextScope();
89
90    if (lhs_scope != NULL && rhs_scope != NULL)
91    {
92        // Same exact scope, lhs is not less than (younger than rhs)
93        if (lhs_scope == rhs_scope)
94            return false;
95
96        SymbolContext lhs_sc;
97        SymbolContext rhs_sc;
98        lhs_scope->CalculateSymbolContext (&lhs_sc);
99        rhs_scope->CalculateSymbolContext (&rhs_sc);
100
101        // Items with the same function can only be compared
102        if (lhs_sc.function == rhs_sc.function &&
103            lhs_sc.function != NULL && lhs_sc.block != NULL &&
104            rhs_sc.function != NULL && rhs_sc.block != NULL)
105        {
106            return rhs_sc.block->Contains (lhs_sc.block);
107        }
108    }
109    return false;
110}
111