1 //===-- ABISysV_ppc64.h ----------------------------------------*- C++ -*-===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 
9 #ifndef LLDB_SOURCE_PLUGINS_ABI_POWERPC_ABISYSV_PPC64_H
10 #define LLDB_SOURCE_PLUGINS_ABI_POWERPC_ABISYSV_PPC64_H
11 
12 #include "lldb/Target/ABI.h"
13 #include "lldb/lldb-private.h"
14 
15 class ABISysV_ppc64 : public lldb_private::RegInfoBasedABI {
16 public:
17   ~ABISysV_ppc64() override = default;
18 
19   size_t GetRedZoneSize() const override;
20 
21   bool PrepareTrivialCall(lldb_private::Thread &thread, lldb::addr_t sp,
22                           lldb::addr_t functionAddress,
23                           lldb::addr_t returnAddress,
24                           llvm::ArrayRef<lldb::addr_t> args) const override;
25 
26   bool GetArgumentValues(lldb_private::Thread &thread,
27                          lldb_private::ValueList &values) const override;
28 
29   lldb_private::Status
30   SetReturnValueObject(lldb::StackFrameSP &frame_sp,
31                        lldb::ValueObjectSP &new_value) override;
32 
33   lldb::ValueObjectSP
34   GetReturnValueObjectImpl(lldb_private::Thread &thread,
35                            lldb_private::CompilerType &type) const override;
36 
37   bool
38   CreateFunctionEntryUnwindPlan(lldb_private::UnwindPlan &unwind_plan) override;
39 
40   bool CreateDefaultUnwindPlan(lldb_private::UnwindPlan &unwind_plan) override;
41 
42   bool RegisterIsVolatile(const lldb_private::RegisterInfo *reg_info) override;
43 
44   // The SysV ppc64 ABI requires that stack frames be 16 byte aligned.
45   // When there is a trap handler on the stack, e.g. _sigtramp in userland
46   // code, we've seen that the stack pointer is often not aligned properly
47   // before the handler is invoked.  This means that lldb will stop the unwind
48   // early -- before the function which caused the trap.
49   //
50   // To work around this, we relax that alignment to be just word-size
51   // (8-bytes).
52   // Allowing the trap handlers for user space would be easy (_sigtramp) but
53   // in other environments there can be a large number of different functions
54   // involved in async traps.
55   bool CallFrameAddressIsValid(lldb::addr_t cfa) override {
56     // Make sure the stack call frame addresses are 8 byte aligned
57     if (cfa & (8ull - 1ull))
58       return false; // Not 8 byte aligned
59     if (cfa == 0)
60       return false; // Zero is not a valid stack address
61     return true;
62   }
63 
64   bool CodeAddressIsValid(lldb::addr_t pc) override {
65     // We have a 64 bit address space, so anything is valid as opcodes
66     // aren't fixed width...
67     return true;
68   }
69 
70   const lldb_private::RegisterInfo *
71   GetRegisterInfoArray(uint32_t &count) override;
72 
73   // Static Functions
74 
75   static void Initialize();
76 
77   static void Terminate();
78 
79   static lldb::ABISP CreateInstance(lldb::ProcessSP process_sp, const lldb_private::ArchSpec &arch);
80 
81   static llvm::StringRef GetPluginNameStatic() { return "sysv-ppc64"; }
82 
83   // PluginInterface protocol
84 
85   llvm::StringRef GetPluginName() override { return GetPluginNameStatic(); }
86 
87 protected:
88   void CreateRegisterMapIfNeeded();
89 
90   lldb::ValueObjectSP
91   GetReturnValueObjectSimple(lldb_private::Thread &thread,
92                              lldb_private::CompilerType &ast_type) const;
93 
94   bool RegisterIsCalleeSaved(const lldb_private::RegisterInfo *reg_info);
95 
96 private:
97   using lldb_private::RegInfoBasedABI::RegInfoBasedABI; // Call CreateInstance instead.
98 
99   lldb::ByteOrder GetByteOrder() const;
100 };
101 
102 #endif // LLDB_SOURCE_PLUGINS_ABI_POWERPC_ABISYSV_PPC64_H
103