ABIMacOSX_i386.h revision 269024 
1//===-- ABIMacOSX_i386.h ----------------------------------------*- 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#ifndef liblldb_ABIMacOSX_i386_h_
11#define liblldb_ABIMacOSX_i386_h_
12
13// C Includes
14// C++ Includes
15// Other libraries and framework includes
16// Project includes
17#include "lldb/lldb-private.h"
18#include "lldb/Target/ABI.h"
19#include "lldb/Core/Value.h"
20
21class ABIMacOSX_i386 :
22    public lldb_private::ABI
23{
24public:
25
26    ~ABIMacOSX_i386() { }
27
28    virtual size_t
29    GetRedZoneSize () const;
30
31    virtual bool
32    PrepareTrivialCall (lldb_private::Thread &thread,
33                        lldb::addr_t sp,
34                        lldb::addr_t func_addr,
35                        lldb::addr_t return_addr,
36                        llvm::ArrayRef<lldb::addr_t> args) const;
37
38    virtual bool
39    PrepareNormalCall (lldb_private::Thread &thread,
40                       lldb::addr_t sp,
41                       lldb::addr_t func_addr,
42                       lldb::addr_t return_addr,
43                       lldb_private::ValueList &args) const;
44
45    virtual bool
46    GetArgumentValues (lldb_private::Thread &thread,
47                       lldb_private::ValueList &values) const;
48
49    virtual lldb_private::Error
50    SetReturnValueObject(lldb::StackFrameSP &frame_sp, lldb::ValueObjectSP &new_value);
51
52protected:
53    virtual lldb::ValueObjectSP
54    GetReturnValueObjectImpl (lldb_private::Thread &thread,
55                    lldb_private::ClangASTType &ast_type) const;
56
57public:
58
59    virtual bool
60    CreateFunctionEntryUnwindPlan (lldb_private::UnwindPlan &unwind_plan);
61
62    virtual bool
63    CreateDefaultUnwindPlan (lldb_private::UnwindPlan &unwind_plan);
64
65    virtual bool
66    RegisterIsVolatile (const lldb_private::RegisterInfo *reg_info);
67
68    virtual bool
69    StackUsesFrames ()
70    {
71        return true;
72    }
73
74    // The Darwin i386 ABI requires that stack frames be 16 byte aligned.
75    // When there is a trap handler on the stack, e.g. _sigtramp in userland
76    // code, we've seen that the stack pointer is often not aligned properly
77    // before the handler is invoked.  This means that lldb will stop the unwind
78    // early -- before the function which caused the trap.
79    //
80    // To work around this, we relax that alignment to be just word-size (4-bytes).
81    // Whitelisting the trap handlers for user space would be easy (_sigtramp) but
82    // in other environments there can be a large number of different functions
83    // involved in async traps.
84    //
85    // If we were to enforce 16-byte alignment, we also need to relax to 4-byte
86    // alignment for non-darwin i386 targets.
87    virtual bool
88    CallFrameAddressIsValid (lldb::addr_t cfa)
89    {
90        // Make sure the stack call frame addresses are are 4 byte aligned
91        if (cfa & (4ull - 1ull))
92            return false;   // Not 4 byte aligned
93        if (cfa == 0)
94            return false;   // Zero is not a valid stack address
95        return true;
96    }
97
98    virtual bool
99    CodeAddressIsValid (lldb::addr_t pc)
100    {
101        // Just make sure the address is a valid 32 bit address.
102        return pc <= UINT32_MAX;
103    }
104
105    virtual bool
106    FunctionCallsChangeCFA ()
107    {
108        return true;
109    }
110
111    virtual const lldb_private::RegisterInfo *
112    GetRegisterInfoArray (uint32_t &count);
113
114    //------------------------------------------------------------------
115    // Static Functions
116    //------------------------------------------------------------------
117    static void
118    Initialize();
119
120    static void
121    Terminate();
122
123    static lldb::ABISP
124    CreateInstance (const lldb_private::ArchSpec &arch);
125
126    //------------------------------------------------------------------
127    // PluginInterface protocol
128    //------------------------------------------------------------------
129    static lldb_private::ConstString
130    GetPluginNameStatic ();
131
132    virtual lldb_private::ConstString
133    GetPluginName();
134
135    virtual uint32_t
136    GetPluginVersion();
137
138protected:
139    bool
140    RegisterIsCalleeSaved (const lldb_private::RegisterInfo *reg_info);
141
142private:
143    ABIMacOSX_i386() : lldb_private::ABI() { } // Call CreateInstance instead.
144};
145
146
147#endif  // liblldb_ABI_h_
148