1 //===-- ABISysV_mips64.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_MIPS_ABISYSV_MIPS64_H
10 #define LLDB_SOURCE_PLUGINS_ABI_MIPS_ABISYSV_MIPS64_H
11 
12 #include "lldb/Target/ABI.h"
13 #include "lldb/lldb-private.h"
14 
15 class ABISysV_mips64 : public lldb_private::RegInfoBasedABI {
16 public:
17   ~ABISysV_mips64() 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   bool IsSoftFloat(uint32_t fp_flag) const;
45 
46   // The SysV mips ABI requires that stack frames be 16 byte aligned.
47   // When there is a trap handler on the stack, e.g. _sigtramp in userland
48   // code, we've seen that the stack pointer is often not aligned properly
49   // before the handler is invoked.  This means that lldb will stop the unwind
50   // early -- before the function which caused the trap.
51   //
52   // To work around this, we relax that alignment to be just word-size
53   // (8-bytes).
54   // Allowing the trap handlers for user space would be easy (_sigtramp) but
55   // in other environments there can be a large number of different functions
56   // involved in async traps.
57   bool CallFrameAddressIsValid(lldb::addr_t cfa) override {
58     // Make sure the stack call frame addresses are 8 byte aligned
59     if (cfa & (8ull - 1ull))
60       return false; // Not 8 byte aligned
61     if (cfa == 0)
62       return false; // Zero is not a valid stack address
63     return true;
64   }
65 
66   bool CodeAddressIsValid(lldb::addr_t pc) override {
67     if (pc & (4ull - 1ull))
68       return false; // Not 4 byte aligned
69 
70     // Anything else if fair game..
71     return true;
72   }
73 
74   const lldb_private::RegisterInfo *
75   GetRegisterInfoArray(uint32_t &count) override;
76 
77   // Static Functions
78 
79   static void Initialize();
80 
81   static void Terminate();
82 
83   static lldb::ABISP CreateInstance(lldb::ProcessSP process_sp, const lldb_private::ArchSpec &arch);
84 
85   static llvm::StringRef GetPluginNameStatic() { return "sysv-mips64"; }
86 
87   // PluginInterface protocol
88 
89   llvm::StringRef GetPluginName() override { return GetPluginNameStatic(); }
90 
91 protected:
92   void CreateRegisterMapIfNeeded();
93 
94   lldb::ValueObjectSP
95   GetReturnValueObjectSimple(lldb_private::Thread &thread,
96                              lldb_private::CompilerType &ast_type) const;
97 
98   bool RegisterIsCalleeSaved(const lldb_private::RegisterInfo *reg_info);
99 
100 private:
101   using lldb_private::RegInfoBasedABI::RegInfoBasedABI; // Call CreateInstance instead.
102 };
103 
104 #endif // LLDB_SOURCE_PLUGINS_ABI_MIPS_ABISYSV_MIPS64_H
105