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 21 class ABIMacOSX_i386 : 22 public lldb_private::ABI 23 { 24 public: 25 ~ABIMacOSX_i386()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 52 protected: 53 virtual lldb::ValueObjectSP 54 GetReturnValueObjectImpl (lldb_private::Thread &thread, 55 lldb_private::ClangASTType &ast_type) const; 56 57 public: 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 // The Darwin i386 ABI requires that stack frames be 16 byte aligned. 69 // When there is a trap handler on the stack, e.g. _sigtramp in userland 70 // code, we've seen that the stack pointer is often not aligned properly 71 // before the handler is invoked. This means that lldb will stop the unwind 72 // early -- before the function which caused the trap. 73 // 74 // To work around this, we relax that alignment to be just word-size (4-bytes). 75 // Whitelisting the trap handlers for user space would be easy (_sigtramp) but 76 // in other environments there can be a large number of different functions 77 // involved in async traps. 78 // 79 // If we were to enforce 16-byte alignment, we also need to relax to 4-byte 80 // alignment for non-darwin i386 targets. 81 virtual bool CallFrameAddressIsValid(lldb::addr_t cfa)82 CallFrameAddressIsValid (lldb::addr_t cfa) 83 { 84 // Make sure the stack call frame addresses are are 4 byte aligned 85 if (cfa & (4ull - 1ull)) 86 return false; // Not 4 byte aligned 87 if (cfa == 0) 88 return false; // Zero is not a valid stack address 89 return true; 90 } 91 92 virtual bool CodeAddressIsValid(lldb::addr_t pc)93 CodeAddressIsValid (lldb::addr_t pc) 94 { 95 // Just make sure the address is a valid 32 bit address. 96 return pc <= UINT32_MAX; 97 } 98 99 virtual const lldb_private::RegisterInfo * 100 GetRegisterInfoArray (uint32_t &count); 101 102 //------------------------------------------------------------------ 103 // Static Functions 104 //------------------------------------------------------------------ 105 static void 106 Initialize(); 107 108 static void 109 Terminate(); 110 111 static lldb::ABISP 112 CreateInstance (const lldb_private::ArchSpec &arch); 113 114 //------------------------------------------------------------------ 115 // PluginInterface protocol 116 //------------------------------------------------------------------ 117 static lldb_private::ConstString 118 GetPluginNameStatic (); 119 120 virtual lldb_private::ConstString 121 GetPluginName(); 122 123 virtual uint32_t 124 GetPluginVersion(); 125 126 protected: 127 bool 128 RegisterIsCalleeSaved (const lldb_private::RegisterInfo *reg_info); 129 130 private: ABIMacOSX_i386()131 ABIMacOSX_i386() : lldb_private::ABI() { } // Call CreateInstance instead. 132 }; 133 134 135 #endif // liblldb_ABI_h_ 136